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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is related to U.S. Provisional Patent Application No. 60/447,369 filed Feb. 14, 2003, from which priority is claimed.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
Not Applicable.
BACKGROUND OF THE INVENTION
The first trailer hitches only consisted of a clevis and a pin, and later a ball mounted on the framework of a tow vehicle or a ball mount inserted into a receiver type hitch. These types of trailer hitches allowed for movement in all directions between the tow vehicle and the trailer. However, all that movement can negatively affect steering, braking, control, and overall vehicle performance. In addition, the increase in gross trailer weights over the years created the need for trailers that can handle different size weights, both large and small.
To accommodate different gross trailer weights, trailer hitches for light vehicles and trailers, such as autos, vans, SUV's, and pickup trucks, are generally one of four ratings, divided into Classes I-IV. For the purposes of this patent application, gross trailer weight is defined as the weight of the trailer when it is fully loaded. Ordinarily, hitches are rated for 10% of gross trailer weight to be on the tongue, referred to as the tongue weight. For the purposes of this patent application, tongue weight is defined as the weight put on a hitch ball by a trailer coupler.
A Class I hitch comprises a framework attached to a tow vehicle including a ball mount and ball for attaching a trailer coupler. This Class is generally rated at 2,000 lb. gross trailer weight. In addition, the ball mount can be either fixed or removable.
A Class II hitch is similar to Class I, except that the rating is generally 3,500 lb. Like Class I, Class II can have either a fixed or removable ball mount.
A Class III hitch only uses a removable ball mount. This style of hitch is known as a “hitch receiver”. In addition to ball mounts, a hitch receiver can be used with other more complicated types of mounts.
A Class IV hitch is similar to Class III, except it is heavier duty. This Class may be rated as high as 14,000 lbs. gross trailer weight.
To handle heavy trailer loads, a weight distribution hitch was invented. As trailer loads increase, tongue weight also increases. When tongue weight increases too much, it pushes down the rear of the tow vehicle causing numerous problems. To counteract this problem, the weight distribution hitch uses spring bars attached to a ball mount and a trailer frame to distribute the tongue weight among all the tow vehicle wheels and all the trailer wheels. As a result, the tow vehicle remains nearer to level from front to back while the trailer is attached. While this type of hitch is a big improvement over previous systems, it does very little to solve the problem of side-to-side movement of the trailer or sway, commonly called fishtail sway.
Fishtail sway is caused by the large distance between the rear axle of the tow vehicle and the hitch assembly and is aggravated by lateral forces against the vehicle caused by winds or passing vehicles. Previous attempts to solve fishtail sway involve stiffening the connection between tow vehicle and trailer by using various methods of friction. While these methods help some, none completely correct the problem.
Fortunately, in U.S. Pat. No. 4,722,542, hereafter referred to as the “Hensley hitch”, the sway problem is effectively corrected by forcing the hitch to turn through converging links that effectively move the pivot point between the tow vehicle and trailer to a point near the rear axle of the tow vehicle. Therefore, this design provides better steering and control of the trailer by eliminating trailer sway. While the converging links do this very well, the gross trailer weight is limited by the size and design of the converging links in '542 because so much of the tongue weight is supported by the converging links. As a result, increasingly heavier tongue weights require larger links, larger bearings, larger spindles, and larger related support systems. Increasing the size of these parts also increases both the hitch weight and the cost of manufacturing. In addition, the Hensley hitch needs workable brakes on the trailer controlled from the tow vehicle. Without trailer brakes or even with surge brakes the converging links tend to move to one side or the other due to the trailer pushing on the hitch assembly when the tow vehicle brakes are applied.
U.S. Pat. No. 5,660,409, hereafter referred to as the “Hensley mini-hitch”, does not need workable brakes on the trailer controlled from the tow vehicle. However, the Hensley mini-hitch is still limited to use on lighter trailers with relatively light tongue weight, because the tongue weight is supported by the on a sliding ball mount. In this design, a strut holds the trailer at a constant distance from the tow vehicle while stopping. In addition, a ball mounted on a sliding mount holds the trailer at a constant distance from the tow vehicle during turns. Still, this design requires maintaining this sliding mechanism as near a zero clearance as possible. To maintain this narrow clearance, fine-tuning and maintenance is required on the sliding mount. Nonetheless, this design is not practical for use with extremely heavy tongue weight.
Therefore, it would be advantageous to have a trailer hitch with a converging links design which does not support tongue weight with the converging links. A trailer hitch of this type could accommodate light and heavy trailer loads without the extra weight and cost associated with larger parts.
SUMMARY OF THE INVENTION
Briefly stated, the invention is a hitch assembly comprising a hitch bar assembly coupled with a hitch receiver of a tow vehicle for transferring pulling and stopping forces to and from the tow vehicle. A hitch box assembly couples with the hitch bar assembly for transferring pulling and stopping forces to and from the hitch bar assembly, the hitch box assembly having a first pivot point. An overcenter latch assembly secures the hitch box assembly to the hitch bar assembly. A front support member pivotally connects to the hitch box assembly at the first pivot point for transferring pulling and stopping forces to and from the hitch box assembly and for pivoting during turns. A strut assembly pivotally connects to the front support member for transferring pulling and stopping forces to and from the front support member wherein the strut assembly can pivot vertically for accommodating uneven roads during driving. Also, the strut assembly includes a second pivot point. A ball mount assembly pivotally connects to the strut assembly at the second pivot point for transferring pulling and stopping forces to and from the strut assembly. The ball mount assembly laterally pivots about the second pivot point within the strut assembly during turns. The ball mount assembly includes a tail tube extending rearwardly. A ball plate assembly attaches to the ball mount assembly for transferring pulling and stopping forces to and from the ball mount assembly. The ball plate assembly includes a hitch ball for removable attachment of the trailer for transferring pulling and stopping forces to and from the trailer. A tail support assembly attaches to a trailer frame and couples with the tail tube whereby the tail support assembly restricts lateral movement of the tail tube and the ball mount assembly so the trailer remains relative to the ball mount assembly at all times. A slide assembly resides within the ball mount assembly such that forces inherent in towing the trailer are not transferred through the slide assembly. The slide assembly slides forwards and backwards to accommodate the change in radial movement of the converging links during turns. Converging links pivotally connect between the hitch box assembly at the first pivot point and the slide assembly whereby the angular position between the first pivot point and slide assembly can be varied. The converging links effectively move the pivot point between the tow vehicle and trailer forward of the hitch assembly. In addition, forces inherent in towing the trailer are not transferred through the converging links. A hanging support assembly attaches to the strut assembly including vertical links pivotally attached to the ball mount assembly for transferring tongue weight from the ball mount assembly through the strut assembly and front support member to the hitch box assembly and hitch bar assembly so tongue weight is not exerted on the converging links or the slide assembly. A jack assembly attaches between the trailer frame and the front support member for distributing tongue weight among tow vehicle wheels and trailer wheels.
The foregoing and other features, and advantages of the invention as well as embodiments thereof will become more apparent from the reading of the following description in connection with the accompanying drawings.
DESCRIPTION OF THE DRAWINGS
In the accompanying drawings which form part of the specification:
FIG. 1 is a perspective view of a trailer connected to a tow vehicle with a hitch assembly constructed in accordance with and embodying the present invention.
FIG. 2 is a top view of a hitch bar and a hitch box assembly.
FIG. 3 is a side view of the hitch bar and the hitch box assembly.
FIG. 4A is a top view of the hitch box assembly.
FIG. 4B is a side view of the hitch box assembly.
FIG. 5A is a partial side view of the hitch assembly of the present invention.
FIG. 58 is a partial top view of the hitch assembly of the present invention.
FIG. 6A is a front view of a ball plate assembly.
FIG. 6B is a side view of a ball mount assembly.
FIG. 7A is a partial top view of a sliding assembly.
FIG. 7B is a partial side view of the sliding assembly.
FIG. 7C is a partial end view of the sliding assembly.
FIG. 8A is a partial top view of the hitch assembly of the present invention during straight travel.
FIG. 8B is a partial top view of the hitch assembly of the present invention during a slight turn.
FIG. 8C is a partial top view of the hitch assembly of the present invention during a sharp turn.
FIG. 9 is a partial perspective view of a tube support assembly.
FIG. 10 is a partial perspective view of a jack assembly.
FIG. 11 is a partial end view of a hanging support assembly.
FIG. 12 is a side view of an alternate embodiment of the invention using a roller assembly.
FIG. 13 is a top view of an alternate embodiment of a front support member and spring bar.
FIG. 14 is a side view of an alternate embodiment of the front support member and spring bar.
FIG. 15 is a side view of an alternate embodiment of the invention using an air bellows.
Corresponding reference numerals indicate corresponding parts throughout the several figures of the drawings.
DETAILED DESCRIPTION
The following detailed description illustrates the invention by way of example and not by way of limitation. The description clearly enables one skilled in the art to make and use the invention, describes several embodiments, adaptations, variations, alternatives, and uses of the invention, including what is presently believed to be the best mode of carrying out the invention.
Referring now to the drawings, particularly FIG. 1 , a tow vehicle 1 is coupled to a trailer 4 with a hitch assembly 10 of the present invention. It will be appreciated by those skilled in the art that the tow vehicle 1 can be any conventional automobile, a van, or truck such as the pickup shown in FIG. 1 . Further, as used in the specification and the claims, the term trailer is intended to include any type of towable device or vehicle that can be pulled behind or trails a tow vehicle. The tow vehicle 1 includes rear wheels 3 which revolve about an axis X. The tow vehicle 1 includes a conventional hitch receiver 2 , which is appropriately secured to the tow vehicle 1 in any conventional or accepted manner.
The trailer 4 has a frame 5 which is supported on wheels 6 that revolve about a common axis Y, and the frame 5 in turn supports a trailer body 7 . The front of the frame 5 forms a so-called tongue or A-frame, in that it has side members 8 which converge forwardly and are connected at their forward ends to a coupler 9 used to secure the trailer 4 to a hitch ball 108 of the hitch assembly 10 . The coupler 9 is a generally spherical socket that opens downwardly and is sized to receive a conventional trailer hitch ball. The coupler 9 also has a conventional locking device which will close upon the hitch ball and retain it in the socket. The coupler 9 may also contain a conventional surge brake. Generally, a surge brake contains a master cylinder that is hydraulically connected through lines to brakes at the wheels of the trailer 4 . A conventional surge brake is actuated when the tow vehicle slows or stops and the forward movement of the trailer 4 urges the master cylinder against the hitch ball, which in turn, causes hydraulic actuation of the brakes at the trailer wheels. The hitch assembly 10 of the present invention can accommodate trailers employing conventional surge brakes as well as trailers employing more exotic braking mechanisms. A typical trailer also includes safety chains and an electric plug.
The present invention has three separate functions: 1) pulling and stopping, 2) sway controlling, and 3) load bearing. In order to better illustrate the three separate functions of the invention, the remaining description is divided into three separate sections with each section concentrating on one of the three functions of the invention.
Pulling and Stopping
As shown in FIGS. 1-6 , for pulling and stopping the trailer 4 the hitch assembly 10 comprises a hitch bar assembly 20 , a hitch box assembly 30 , an over-center latch assembly 50 , a front support member 70 , a strut assembly 90 , and a ball mount assembly 100 . Together, these assemblies connect the tow vehicle 1 to the trailer 4 for transferring the pulling and stopping forces of the tow vehicle 1 to the trailer 4 . More importantly, none of the pulling and stopping forces are transferred through converging links 140 , which will be described below in greater detail.
As shown in FIGS. 2 and 3 , the hitch bar assembly 20 is a square bar 21 that inserts into the hitch receiver 2 and projects rearwardly in a generally horizontal orientation with its longitudinal axis along the centerline of the tow vehicle 1 . The hitch bar assembly 20 fits snugly into the hitch receiver 2 with very little clearance and is secured by inserting a standard hitch pin 22 and clip 23 into corresponding through holes 24 . The hitch bar assembly 20 includes over-center latch tabs 25 welded to each side of the bar 21 at the mid-section. The tabs 25 project laterally from the bar 21 and define through holes 24 , concave recesses 26 , and roll pins 27 for coupling with the over-center latch assembly 50 to be described below. The hitch bar assembly 20 also includes stops 28 welded to the rear of the tabs 25 on all four sides of the bar 21 for mating with the hitch box assembly 30 to be described below. The stops 28 are wedges with beveled faces facing rearwardly with an angle of about 20°.
The hitch box assembly 30 is similar to the one disclosed in U.S. Pat. No. 4,811,967, hereby incorporated by reference, which mates with the hitch bar assembly 20 . As shown in FIGS. 4A and 4B , the hitch box assembly 30 comprises an outer hitch box 31 and an inner hitch box 38 . The outer hitch box 31 comprises four sidewalls 32 which are joined together to form a square box-like enclosure defining an opening 33 for receiving the inner box 38 . To insure a tight fit, the inner dimensions of the outer hitch box 31 are sized to fit closely over the outer dimensions of the inner hitch box 38 . The inner hitch box 38 comprises four angular walls 39 joined to form a funnel-shaped enclosure that narrows from a front end 40 to a back end 41 for receiving the hitch bar assembly 20 . The interior dimensions of the angular walls 39 should provide enough clearance so the bar 21 of the hitch bar assembly 20 can extend to the rear of the hitch box 30 when inserted. In addition, the walls 39 are angled to match the beveled faces of the stops 28 of the hitch bar assembly 20 for proper seating.
The inner hitch box 38 is secured to the outer hitch box 31 by welding the front end 40 to the sidewalls 32 and welding two fillers 42 horizontally between the back end 41 and the sidewalls 32 . The inner hitch box 38 is secured inside the outer hitch box 31 so the back end 41 is raised slightly higher than the front end 40 at approximately a five-degree angle. The back end 41 is raised higher to compensate for looseness and weakness in the hitch receiver 2 when spring bars 84 are tensioned. When the spring bars 84 are tensioned, the hitch receiver 2 may angle slightly downward. Therefore, the five-degree angle serves to keep the hitch box assembly 30 nearer to horizontally level.
The outer hitch box 31 also comprises four front tabs 34 for attaching the over-center latch assembly 50 and four back tabs 36 for attaching converging steering links 140 , which are described below in the steering section. The front tabs 34 and back tabs 36 define respective through holes 35 and 37 . The front tabs 34 are welded at the frontward sides of the outer hitch box 31 at the top and bottom projecting laterally so the through holes 35 align. The back tabs 36 are welded to the bottom rearward sides of the outer hitch box 31 projecting laterally so the through holes 37 align. The back tabs 36 should define a gap between themselves large enough to provide a narrow clearance for inserting the converging steering links 140 .
As shown in FIGS. 2 and 3 , the over-center latch assembly 50 is similar to the one disclosed in U.S. Pat. No. 4,811,967, which is used to secure the hitch box 30 to the hitch bar assembly 20 . The over-center latch assembly 50 includes a left latch 51 and right latch 52 each comprising a pair of connecting links 53 , a vertical tube 56 , a pivot pin 57 , a thrust link 59 , a latch pin 61 , and a safety pin 62 . Each connecting link 53 is a straight bar defining front through holes and back through holes. The pair of connecting links 53 are connected in parallel by hingedly attaching the pivot pin 57 between the front holes and by fixedly attaching the hollow vertical tube 56 between the back holes. The pivot pin 57 defines a transversely directed threaded bore for receiving the thrust link 59 located midway between the two connecting links 53 . The thrust link 59 is a threaded rod with a cross head 60 which inserts into the threaded bore of the pivot pin 57 so the surface of the cross head 60 is presented away from the pivot pin 57 for engaging the latch tabs 25 of the hitch bar assembly 20 . The thrust link 59 can be screwed either in or out of the threaded bore to allow for any adjustment needed to ensure a tight fit with the latch tabs 25 . To rotate the pivot pin 57 and thrust link 59 about a vertical axis, hexagonal heads 58 are attached to each end of the pivot pin 57 . The hexagonal heads 58 can be engaged by a conventional end, socket or box wrench to rotate the pivot pin 57 and thrust link 59 to engage and disengage the hitch bar assembly 20 . The left latch 51 and right latch 52 are attached to respective front tabs 34 of the hitch box 30 by inserting each latch 51 and 52 in between the top and bottom front tabs 34 so the vertical tubes 56 align with the through holes 35 . To secure both latches 51 and 52 , latch pins 61 are inserted through the front tabs 34 into the vertical tubes 56 so the latches 51 and 52 can rotate about a vertical axis. For additional security, the latch pins 61 are secured with cotter pins 63 .
To secure the hitch bar assembly 20 to the hitch box assembly 30 the bar 21 of the hitch bar assembly 20 inserts into the hitch box assembly 30 until the stops 28 seat against the walls 39 of the inner hitch box 38 . The latches 51 and 52 pivot from a slightly outward direction to a slightly inward position, referred to as the over-center position so the connecting links 53 rest against the roll pins 27 of the latch tabs 25 . A conventional end, socket or box wrench engages the hexagonal heads 58 of the pivot pins 57 and rotates the pivot pins 57 and thrust links 59 so the cross heads 60 engage the recesses 26 of the latch tabs 25 , also referred to as the over-center position. In this position, the hitch box assembly 30 is prevented from moving laterally or vertically with respect to the hitch bar assembly 20 . Of course, the over-center latch assembly 50 prevents the hitch box assembly 30 from pulling away from the hitch bar assembly 20 . For extra safety, the safety pins 62 are inserted into the through holes 24 of the latch tabs 25 . The safety pins 62 prevent the latches 51 and 52 from moving outwardly away from the over-center position. Of course, before anyone attempts to swing either latch 51 or 52 outwardly in order to disconnect the hitch box assembly 30 , the safety pins 62 must be removed.
The hitch box assembly 30 also includes an upper king pin 43 and a lower king pin 44 for pivotally connecting to the front support member 70 at a first pivot point 11 . The upper king pin 43 inserts into a through hole at the top rear of the outer hitch box 31 and fixedly attaches to the inner hitch box 38 so the upper king pin 43 protrudes upwardly out of the hitch box assembly 30 . The lower king pin 44 inserts into a through hole at the bottom rear of the outer hitch box 31 and fixedly attaches to the inner hitch box 38 so the lower king pin 44 protrudes downwardly out of the hitch box assembly 30 and is vertically aligned with the upper king pin 43 .
As shown in FIGS. 5A , 5 B, 6 A, and 6 B, the front support member 70 comprises an upper crossbar 71 , a lower crossbar 72 , side caps 73 , spring bar tubes 74 , and side support plates 75 . Both the upper crossbar 71 and lower crossbar 72 are straight rectangular tubes defining respective vertical through holes 77 and 78 and at the midsection of each tube for pivotally connecting to respective upper king pin 43 and lower king pin 44 at the first pivot point 11 . The spring bar tubes 74 are straight square tubes that weld to each end of the lower crossbar 72 so they extend rearwardly and horizontally for receiving the spring bars 84 . In addition, the spring bar tubes 74 should extend at an outward angle. When the spring bars 84 are inserted into the spring bar tubes 74 , the outward angle allows the spring bars 84 to pivotally attach to the trailer frame 5 via the jack assembly 80 to be described below. The side support plates 75 are rectangular plates defining through holes at a top end for bolting to the side caps 73 . The side support plates 75 are welded to the top edges of the spring bar tubes 74 so the plates 75 extend rearwardly and vertically, thus joining the side support plates 75 to the lower crossbar 72 . The side caps 73 are flat plates welded to each end of the upper crossbar 71 extending rearwardly and horizontally and define through holes for connecting to the side support plates 75 . The side support plates 75 also include strut pins 76 which protrude outwardly and horizontally for connecting to the strut assembly 90 to be described below. The strut pins 76 are located so they are near alignment with the center of converging steering links 140 when the hitch assembly 10 is completely assembled.
To attach the front support member 70 to the hitch box assembly 30 , the lower crossbar 72 is pivotally attached to the lower king pin 44 by inserting the lower kingpin 44 into the through hole 78 . The upper crossbar 71 is pivotally attached to the upper king pin 43 by inserting the upper king pin into the through hole 77 . Using bolts 79 , the side support plates 75 are fixedly attached to the side caps 73 . When assembled, the front support member 70 provides a stable pivoting connection between the hitch box assembly 30 and the strut assembly 90 at the first pivot point 11 .
The strut assembly 90 is an arch-shaped frame that connects the front support member 70 to the ball mount assembly 100 at a second pivot point 12 for transferring pulling and stopping forces. The strut assembly 90 also supports the hanging support assembly 150 to be described below in greater detail. The strut assembly 90 comprises two side tubes 91 and two rear caps 92 . The side tubes 91 are arched tubes with front ends that pivotally connect to the strut pins 76 of the front support member 70 so the tubes 91 can pivot vertically but are rigid laterally. Vertical pivoting of the strut assembly 90 through the tubes 91 accommodates uneven roads or drives in which the front of the tow vehicle 1 would be higher or lower than the rear of the tow vehicle 1 . The side tubes 91 extend rearwardly and horizontally so both tubes 91 arch inwardly. The rear caps 92 are rectangular plates welded laterally between the tops and bottoms at the rear ends of the side tubes 91 to complete the arch-shaped frame. The rear caps 92 include a ball mount pin 93 vertically connecting the midsections of each cap 92 for pivotally connecting to the ball mount assembly 100 . When assembled, the strut assembly 90 extends rearwardly beneath the trailer frame 5 and pivotally attaches to the rear of the ball mount assembly 100 at the second pivot point 12 .
The ball mount assembly 100 is a frame with a rectangular front end and a V-shaped rear end that connects the strut assembly 90 to the trailer 4 for transferring pulling and stopping forces. The ball mount assembly 100 comprises side channels 101 , vertical supports 102 , a ball plate assembly 104 , and a tail tube 109 . The two side channels 101 are C-shaped channels that extend rearwardly and horizontally parallel with each open-channel side facing inward. The rear ends of the channels 101 angle inward and are welded together forming a V-shape that mirrors the arch-shape of the strut assembly 90 . The vertical supports 102 are rectangular plates defining a plurality of through holes 103 for attaching the ball plate assembly 104 at multiple heights. The vertical supports 102 are welded vertically to the top front ends of the channels 101 .
As shown in FIGS. 6A and 6B , the ball plate assembly 104 is a horizontal crossbar 105 with side supports 106 welded to each end of the crossbar 105 extending downward and a hitch ball 108 mounted to the top center of the crossbar 105 . The side supports 106 define through holes 107 for attaching to the vertical supports 102 . The tail tube 109 is a straight tube welded to the rear end of the channels 101 so the tail tube 109 extends rearwardly and horizontally for engaging a tail support assembly to be described below in greater detail.
To assemble, the ball plate assembly 104 is bolted to the vertical supports 102 at an appropriate height by aligning holes 107 of the ball plate assembly 104 with the appropriate holes 103 of the vertical support 102 and inserting bolts 110 . The entire ball mount assembly 100 is pivotally attached to the ball mount pin 93 of the strut assembly 90 by inserting the ball mount pin 93 through a hole at the intersection of the side channels 101 . This pivoting connection allows the ball mount assembly 100 to pivot laterally within the strut assembly 90 . In addition, the tail tube 109 couples with the tail support assembly 130 to be described below in greater detail in the steering section. To complete the assembly, the trailer 4 attaches to the ball mount assembly 100 by coupling the hitch ball 108 with the coupler 9 . Ordinarily, the typical ball-and-socket trailer hitch accommodates universal movement, but in the present invention, the trailer 4 is prevented from turning relative to the hitch ball 108 by the ball mount assembly 100 and the tail support assembly 130 . Instead, this movement is accommodated by the converging links 140 and the slide assembly 120 described below in the steering section. However, the trailer 4 is free to rock from side-to-side on the hitch ball 108 in reference to the tow vehicle 1 and the rear of the ball mount assembly 100 where the tail tube 109 slides into the tail support assembly 130 .
In operation, the pulling and stopping forces are transferred from the tow vehicle 1 through the hitch receiver 2 to the hitch bar assembly 20 , from the hitch bar assembly 20 to the hitch box assembly 30 , from the hitch box assembly 30 to the front support member 70 , from the front support member 70 to the strut assembly 90 , from the strut assembly 90 to the ball mount assembly 100 , and finally, from the ball mount assembly 100 to the trailer 4 . As mentioned above, none of the pulling and stopping forces are transferred through the converging links 140 .
Steering
As shown in FIGS. 7-9 , the steering function of the hitch assembly 10 of the present invention is accomplished through a slide assembly 120 , a tail support assembly 130 , and converging links 140 . The converging links 140 are similar to the ones disclosed in U.S. Pat. No. 4,722,542 and U.S. Pat. No. 5,660,409, hereby incorporated by reference. The slide assembly 120 , tail support assembly 130 , and converging links 140 effectively move the pivot axis for the hitch assembly 10 to near the rear axle of the tow vehicle 1 . This projection of the pivot axis provides the hitch assembly 10 with good lateral stability with little or no tendency to sway or fishtail when buffeted by cross winds or when otherwise subjected to lateral forces. However, in the present design the converging links 140 do not carry any tongue weight and they do not transfer pulling or stopping forces, as described above.
The slide assembly 120 comprises guides 121 , slide plates 122 , crosslinks 126 , and crosslink brackets 127 . The guides 121 are plastic rectangular bars attached along the inside of the side channels 101 of the ball mount assembly 100 to act as bearing surfaces for supporting and guiding the slide plates 122 . The slide plates 122 are rectangular plates with a cutout in a front end defining two link tabs 123 and corresponding holes 124 for attaching the converging links 140 . The two slide plates 122 are welded together one on top of the other with evenly spaced spacers 125 so there is a gap between the plates 122 for receiving the guides 121 . When assembled, the slide plates 122 reside within the side channels 101 of the ball mount assembly 100 so the slide plates 122 slide forward and backward along the guides 121 . Located between the slide plates 122 is a pair of horizontal crosslinks 126 which are parallel to one another. One end of the crosslinks 126 is pivotally attached to one side of the slide plates 122 and runs crossways between the slide plates 122 . The other end of the crosslinks 126 protrudes through corresponding openings cut out of one of the side channels 101 . The protruding crosslink 126 ends are pivotally attached to a pair of crosslink brackets 127 which are welded to the outside face of the side channels 101 .
As described above, the rear of the ball mount assembly 100 has an extended tail tube 109 that engages the tail support assembly 130 . The tail support assembly comprises a U-bolt plate 131 , a channel 133 , and a tail bracket 135 . The U-bolt plate 131 is a rectangular plate with an angled channel tab 132 extending laterally for supporting the channel 133 . Each U-bolt plate 131 is clamped to the bottom of each trailer side member 8 using U-bolts 134 so the channel tabs 132 face inwardly and align parallel with each other. The channel 133 attaches between the channel tabs 132 so the channel 133 can be adjusted laterally for centering the tube support assembly 130 relative to the trailer 4 . The tail bracket 135 attaches to the underside of the channel 133 and extends downward so a roller 136 is parallel with the channel 133 .
When assembled, the tail tube 109 rests snuggly inside the tail bracket 135 . Although the roller 136 allows the tail tube 109 to move forward and backward along the longitudinal axis of the ball mount assembly 100 , the tail bracket 135 restricts any other lateral movement of the tail tube 109 . The ability to move forward and backward accommodates any such motion created by the use of surge brakes. Since the trailer 4 is rigidly attached to the tail support assembly 130 , the longitudinal axis of the trailer 4 remains parallel with the longitudinal axis of the tail support assembly 130 at all times.
The converging links 140 are straight links of equal length having spherical bearings 141 on each end for pivotally connecting the hitch box assembly 30 to the slide assembly 120 . The front ends of the converging links 140 are pivotally attached to the back tabs 36 of the hitch box assembly 30 with link pins 142 . The rear ends of the converging links 140 pivotally attach to the link tabs 123 of the slide assembly 120 with link pins 142 . The spherical bearings 141 allow the converging links 140 to pivot in any direction to prevent any misalignment during turns, inclines, or declines.
When assembled, the converging links 140 are equidistant from the centerline M and converge forwardly. The convergence is such that the links 140 , if extended forwardly, will intersect along a centerline M perhaps ahead of the rear of the tow vehicle 1 , perhaps ahead of the rear wheels 6 . When the trailer 4 is directly behind the tow vehicle 1 , the links 140 are symmetrically positioned. When the trailer 4 shifts to one side or the other during turns, the convergence intersection transfers to points which are closer to the hitch box assembly 30 and offset from the centerline M. Together, the converging links 140 and slide assembly 120 effectively move the pivot axis for the hitch assembly 10 to near the rear axle of the tow vehicle 1 .
The relative relationship of the elements of the hitch assembly 10 when the tow vehicle 1 and trailer 4 are negotiating turns are shown in FIGS. 8A , 8 B, and 8 C. As the tow vehicle 1 turns relative to the trailer 4 , the hitch bar assembly 20 and hitch box assembly 30 necessarily move in the direction of hitch receiver 2 on the tow vehicle 1 . The front support member 70 and strut assembly 90 pivot at the first pivot point 11 . Simultaneously, the converging links 140 pivot to allow turning while maintaining the effective hitch pivot axis near the rear of the tow vehicle 1 . As the individual links 140 pivot, the relative radius of the links 140 shorten drawing the slide assembly 120 forward towards the hitch box assembly 30 and the ball mount assembly 100 pivots at the second pivot point 12 . As the tow vehicle 1 turns sharper, the ball mount assembly 100 will pivot at the second pivot point 12 until it rests nearly against the strut assembly 90 . As mentioned above, the trailer 4 remains parallel with the longitudinal axis of the ball mount assembly 100 because the trailer 4 is rigidly attached to the ball mount assembly 100 and the tail support assembly 130 . Since ball mount assembly 100 with the hitch ball 108 and trailer 4 attached thereto, are held in place at the second pivot point 12 by strut assembly 90 , the trailer 4 remains a predetermined distance away from the tow vehicle 1 (e.g. the length of the strut assembly minus the length of the ball mount assembly plus a small change in the radius of ball mount assembly as it moves side-to-side). Therefore, braking of the tow vehicle even without the use of good trailer brakes doesn't allow pressure to be exerted on the converging links.
In this way the converging links 140 steer the trailer 4 and the sliding movement of the slide assembly 120 accommodates the change in radial movement of the converging links 140 during turns. However, neither the slide assembly 120 nor the converging links 140 carry any of the tongue weight as in previous designs. Instead, the tongue weight is carried on a hanging support assembly 150 to be described below in the weight carrying section. As a result, the present invention allows for more tongue weight without adding to the cost and weight by increasing the size of the converging links and all associated components as in previous designs. In addition, adjustable blocks are not needed to keep the side movement of the ball mount assembly 100 to near zero clearance. Instead, the present invention uses two parallel crosslinks 126 which eliminate the need for fine-tune or maintenance as in previous designs.
Weight Carrying
Generally, the present invention can handle greater gross trailer loads than previous designs. In the present invention, this is accomplished by not carrying any tongue weight with the converging links 140 , as mentioned above. Instead, the hanging support assembly 150 carries the tongue weight, which keeps the converging links 140 approximately level with the hitch assembly 10 at all times. In addition, spring bars 84 and the jack assembly 80 distribute the tongue weight among all the tow vehicle wheels 3 and all the trailer wheels 6 . As a result, the present invention relates to Class III or heavier rated hitch systems.
The hanging support assembly 150 comprises a support frame 151 and a pair of vertical links 154 . The support frame 151 is an arch-shaped frame including legs 152 that rigidly attach vertically to the front end of the strut assembly 90 and a crossbar 153 connecting the legs 152 . The support frame 151 should be attached directly over the side supports 106 of the ball plate assembly 104 with the crossbar 153 parallel with the front support member 70 . The vertical links 154 are straight links with spherical bearings 155 attached at each end for connecting the support frame 151 to the side channels 101 of the ball mount assembly 100 . Top ends of the vertical links 154 pivotally connect to the crossbar 153 so the vertical links 154 hang parallel to each other. Bottom ends of the vertical links 154 pivotally connect to respective side channels 101 . The spherical bearings 155 allow the ball mount assembly 100 to pivot during turning as described above. When assembled, the tongue weight placed on the ball mount assembly 100 by the trailer 4 is transferred to the hanging support assembly 150 via the vertical links 154 . The hanging support assembly 150 transfers the weight through the strut assembly 90 and front support member 70 to the hitch box assembly 30 and hitch bar assembly 20 , which are supported by the hitch receiver 2 . As will be described below, the springs bars 84 and jack assembly 80 distribute the weight among all the tow vehicle wheels 3 and all the trailer wheels 6 . As a result, the tongue weight is transferred to the tow vehicle 1 and the trailer 4 without placing any tongue weight on the converging links 140 .
Those skilled in the art will recognize that alternative embodiments may be used in place of the hanging support assembly 150 to carry the tongue weight. For example, FIG. 12 illustrates a roller assembly 160 for supporting the tongue weight on the hitch assembly 10 . The roller assembly 160 comprises a pair of roller supports 161 , a pair of rollers 163 , a C-channel 166 , and a channel support 169 . Each roller support 161 is a flat plate that welds to the bottom of a respective side channel 101 of the ball mount assembly 100 so that roller tabs 162 extend forwardly. The rollers 163 pivotally attach to each roller tab 162 so they can engage the C-channel 166 . The C-channel 166 is welded between the side tubes 91 of the strut assembly 90 with the opening of the C-channel 166 facing the rollers 163 for engagement. The C-channel 166 includes a spacer 167 and a wear plate 168 along an inner bottom surface. When assembled the rollers 163 fit inside the C-channel 166 so the rollers 163 can roll back and forth along either the wear plate 168 or the top inner surface of the C-channel 166 . The channel support 169 attaches to the midsection of the C-channel 166 to provide additional support to the C-channel 166 . The channel support 169 includes two tabs 170 that respectively attach to the top and bottom of the C-channel 166 . A bolt 171 and spacer 172 connect the two tabs. During operation, tongue weight is transferred from the hitch ball 108 and ball mount assembly 100 through the roller assembly 160 to the front support member 70 . As described above, the tongue weight then transfers from the front support member 70 to the hitch box assembly 30 and hitch bar assembly 20 , which are supported by the hitch receiver 2 . Finally, the springs bars 84 and jack assembly 80 distribute the weight among all the tow vehicle wheels 3 and all the trailer wheels 6 . As a result, the tongue weight is transferred to the tow vehicle 1 and the trailer 4 without placing any tongue weight on the converging links 140 .
As mentioned above, the spring bars 84 are inserted into the spring bar tubes 74 located on the front support member 70 extending rearwardly and horizontally at an outward angle so they can attach to the trailer frame 5 via the jack assembly 80 . The outward angle positions the rear ends of the spring bars 84 into near alignment with the side members 8 of the trailer's A-frame. The spring bars 84 also slope downward toward the rear to allow for tensioning.
The jack assembly 80 comprises a pair of jacks 81 , jack brackets 82 , spring bar links 83 , and the spring bars 84 . The jack brackets 82 are L-shaped brackets secured to the top of the side members 8 of the trailer 4 by the same U-bolts 134 used to secure the U-bolt plates 131 . However, the jack brackets can be secured by any other conventional means, such as welding or independent U-bolts. The jacks 81 are vertically welded to the jack brackets 82 so each jack 81 resides in a recess of the U-bolt plate 131 . The spring bars 84 are attached to the jacks 81 with the spring bar links 83 . The upper end of each spring bar link 83 is pivotally attached to each jack 81 and the lower end of the each link 83 is pivotally attached to each spring bar 84 . Consequently, the jacks 81 can tension the spring bars 84 while still allowing pivotal movement during turns. The jacks 81 should be cranked until appropriate tension is applied to the spring bars 84 . Spring bars have long been used in conjunction with trailer hitches to achieve better weight distribution among all the tow vehicle wheels and all the trailer wheels, and the principle will therefore not be described in more detail here.
Changes can be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. For example, the spring bars 84 and front support member 70 can be modified to accommodate different shapes and sizes of trailer frames. In one alternate embodiment shown in FIGS. 13 and 14 , the front support member 70 includes inner plates 180 parallel to the side support plates 75 . The plates 180 and 75 should be spaced appropriately for receiving the spring bars 84 . In this alternate embodiment, the spring bars 84 are round L-shaped bars. The spring bars 84 are pivotally attached to bushings 181 located between the plates 180 and 75 . Using an adjustable T and washers 182 attached to the plates 180 and 75 , the spring bars 84 can pivot to accommodate different shape and sizes of trailer frames. It should be noted that in this alternate embodiment, the spring bar tubes 74 of the front support member 70 described above are not included.
In another alternate embodiment shown in FIG. 15 , the jack assembly 80 is replaced with an air bellows assembly 190 for distributing the tongue weight among all the tow vehicle wheels 3 and all the trailer wheels 6 . In this embodiment, the spring bars 84 attach to a bellows bracket 191 . The bellows bracket 191 pivotally attaches between the front support member 70 and a shock absorber 192 . The shock absorber pivotally attaches to the trailer frame 6 . The bellows bracket 191 rests on an adjustable air bellows 193 . In operation, the air bellows 193 adjusts similar to the jacks 81 of the first embodiment to equalize the tongue weight.
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A hitch assembly for coupling a trailer to a tow vehicle includes a number of assemblies, including converging links and a slide assembly, that effectively places the pivot point for the trailer ahead of the actual hitch assembly, which in turn enhances the stability of the combination tow vehicle and trailer, rendering it less susceptible to swaying or fishtailing. This is done without placing tongue weight on converging links or the slide assembly so that the hitch assembly can accommodate a larger gross trailer load.
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[0001] The present invention relates to electronic devices, and in particular to electronic communications devices having voice activated functions.
BACKGROUND OF THE INVENTION
[0002] It is currently known to provide electronic devices such as mobile telephones with voice activated functions. For example, some mobile telephones make use of voice activated dialling (VAD) to simplify dialling of calls from the telephone.
[0003] [0003]FIG. 1 of the accompanying drawings schematically shows a device having a device controller 2 which controls various device functions 4 . A digital signal processor (DSP) 8 is provided to receive voice inputs 10 from a user. The DSP 8 includes a voice comparison function 81 which compares the voice input 10 with voice signal data stored in DSP data storage 82 . The output of the voice comparison function 81 serves to control the device functions 4 , via the controller 2 , in response to the received voice inputs. The DSP 8 receives the voice input 10 and compares it with entries in a user defined library of voice signals (or “voice tags”). The library of voice tags is received from device data storage 6 (particularly a voice tag data library area 62 ) whenever voice activation is selected. The DSP data storage 62 is also generally used to store data relating to other functions of the DSP 8 , for example for use in noise reduction. Part of a library of voice tags for a voice activated dialling telephone is shown in FIG. 2. The telephone can be instructed to dial a telephone number simply by the user speaking the name of the person in the list. The voice tag data is stored by the user of the telephone.
[0004] The voice tag data library is transferred to the DSP each time voice activation is used. However, this requirement means that the number of voice tags that can be stored in the device is limited by speed, size and cost constraints of producing the DSP, since a large number of tags would take a long time (comparatively) to transfer between the device storage 6 and the DSP storage 8 , and providing large memory in the DSP can add significantly to the size and cost of the DSP. A conventional voice tag data library typically stores around ten to fifteen voice tags.
[0005] Another feature of some electronic devices, most notably mobile telephones and mobile companions/organisers, is the provision of preferred operating modes in which groups of operating parameters of the device can be set simply by choosing the appropriate operating mode, or “profile”. For example, for a mobile telephone, different parameters can be set for use in a meeting compared to those required for use in a car. Examples of typical profiles for a mobile telephone are: Normal (default), Meeting, In Car, Outdoors, Portable Hands-free, and Home. Typical settings for the various profiles are shown in FIG. 3.
[0006] In the device shown in FIG. 1, data relating to the various operating modes are stored in a profiles data area 61 of the device data storage 6 , and are recalled by the controller 2 . The user of the device can choose when to change profile, or the profile can be changed automatically, for example by connection of accessories, or by reference to time or location.
SUMMARY OF THE INVENTION
[0007] According to one aspect of the present invention, there is provided an electronic device comprising control means for providing the device with a plurality of selectable operating modes, the operating modes defining respective set of operating parameters for functions of the device, voice detection means for receiving an input voice signal and for providing voice activation of at least one function of the device, the voice detection means being operable to compare an input voice signal with a library of stored voice signals to determine the operation of the device corresponding to the input voice signal, wherein the stored voice signals are stored by the user of the device, and wherein each operating mode has a specific associated library of stored voice signals for use by the voice detection means when the operating mode concerned is selected.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] [0008]FIG. 1 is a schematic diagram of a voice activated electronic device;
[0009] [0009]FIG. 2 illustrates part of a stored library of voice tags;
[0010] [0010]FIG. 3 illustrates various operating mode settings of a mobile telephone;
[0011] [0011]FIG. 4 is a schematic diagram of a storage element for use in a device in accordance with the present invention; and
[0012] [0012]FIG. 5 illustrates various operating mode settings of a mobile telephone embodying the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0013] [0013]FIG. 4 of the accompanying drawings illustrates schematically a storage area for use in a device according to the invention. The device includes the other elements shown in FIG. 1, namely a device controller 2 , which serves to control device functions 4 , and a DSP 8 . The device storage 6 includes areas for storing respective profile data ( 61 A, 61 B, 61 C), relating to the different operating modes (A, B, C) of the device. As described above, the device controller 2 sets the operating parameters for the device functions 4 in accordance with the data stored in a selected profile data area 61 A, 61 B or 61 C. For selected functions, the controller 2 is responsive to input signals from the DSP 8 in order to control the device in accordance with received voice signals.
[0014] As described above, the voice comparison function 81 of the DSP 8 operates to compare a voice input 10 with a stored voice tag data, and outputs to the controller an indication of the function to which the voice input relates.
[0015] In a device according to the present invention, the device data storage 6 includes additional storage areas for storing respective libraries of voice tags for use by the DSP 8 . The device data storage 6 is not simply an enlarged voice tag storage area, since, as described above, the delay in voice processing caused by the use of such an external storage area would be too high to enable efficient voice activation of device functions.
[0016] In accordance with the present invention, the device data storage 6 is used for storing separate libraries 62 A, 62 B, 62 C of voice tags, each library being associated with a respective profile (operating mode) of the device. Thus, when voice activation is selected, the voice tag library associated with the current profile is loaded into the DSP 8 for use in the voice activation of functions of the device. In this way, the effective number of voice tags that can be stored by the device can be increased without causing undue delays in voice processing. The libraries of tags are set up and stored by the user (or users) of the device.
[0017] Using the mobile telephone example, one profile could be used to define the use of the telephone for business purposes. In such a setting a specific business-oriented voice tag library can be used. This could contain, for example, business contact numbers. When the telephone is then switched to a home setting at the end of the day, the voice tag library is updated using a “home” library stored in the device data storage 6 . This home library could contain, for example, contact numbers for family and friends. If necessary some names (spouse, boss etc.) can be stored in both lists. Alternatively, a single list of voice tags can be stored in the device data storage, with the voice tag library data selecting a number of entries from the list for use with a particular profile.
[0018] The following list illustrates possible uses for specific function related libraries, particularly with relation to mobile telephones. In each example two options are described but in reality the choice need not be limited to two and any or all of the options below may be combined. It will be readily appreciated that any of the functions on a mobile telephone might be voice activated, and that voice activated dialling is presented here merely as an example.
[0019] [0019]FIG. 5 illustrates various operating mode settings of a mobile telephone embodying the present invention, and it will be noted that each operating mode is specified with a particular voice tag library applicable to that mode of operation.
[0020] Work vs. Home
[0021] Different voice dialling lists can be used for the different modes, as described above.
[0022] Work vs. Car
[0023] In addition to selecting specific lists of voice tags for use in work and car, the profile can be used to reject incoming calls from specified people. The user may choose only to receive calls from people on the list associated with the Car Profile while driving. When using hands free mode in the car the phone can announce who is calling using a voice confirmation mode. The voice tags stored for the voice confirmation are stored in a specific “car” library.
[0024] Country A vs. Country B
[0025] Use different libraries depending on which country the user is in. The given Country Profile may be selected by the user or possibly be chosen automatically when the phone identifies that it is in a particular land. The country profile can then use a specific list for voice activated dialling, for example.
[0026] Time Period A vs. Time Period B
[0027] The telephone automatically changes the user profile and hence the list of names for VAD at the end of the working day. Alternatively the phone can be programmed to change profile after a pre-set time interval (e.g. in 2 hours' time).
[0028] User A vs. User B
[0029] If more than one person uses the telephone then they can have their own profiles with their own lists of names. This gives additional advantages as the two users will record their lists of names independently and may well have the same names for different people. Any possible confusion can be avoided by selecting the correct profile. The different users will also have different pre-recorded commands for voice answering etc (e.g. yes, no, answer,) which will be associated with the profile. Enabling the use of specific lists for specific profiles will enable multiple users to use a telephone because each user will be able to store their own voice tag library which is associated only with their specific profile.
[0030] Two Telephone Lines From One Phone
[0031] This can be associated with any of the situations listed above (e.g. one line for home, one for work or one subscription in Country A another in Country B). The relevant profile can be chosen by the user or selected automatically when changing lines. The voice activation commands relating to the different lines, and possibly different operators, are then automatically loaded into the DSP memory from the library concerned.
[0032] It will be readily appreciated that the use of profile-specific libraries of stored voice tags is not only applicable for use on mobile telephones; voice activation of functions in other electronic devices such as PCs, hand held computers and communicators is also possible. Multiple stored voice tag libraries can enable multiple users to use voice activated commands, by allowing each user to pre-record a voice tag library. WAP (wireless application protocol) enabled mobile telephones are also suitable for use in such a way.
[0033] It will therefore be appreciated that an electronic device embodying the present invention can usefully store a large number of voice tags, but can retain the speed and cost advantages of having a digital signal processor containing a small amount of memory.
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An electronic device has a plurality of user selectable operating modes. Each operating mode defining a set of operating parameters for the device. The device also has at least one voice activated function which is responsive to an input voice signal. The reference voice signals are stored in the device by a user of the device and are stored in groups, each of which relates to a specific operating mode of the telephone.
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This application is a continuation-in-part of my copending application Ser. No. 894,492, filed Apr. 7, 1978 now abandoned and entitled "FlashLight".
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to portable battery operated devices and has particular reference to portable flashlights.
2. Description of the Prior Art
Heretofore, flashlights of the above type have had a tendency to periodically malfunction due principally to build-up of oxidation and/or dirt on the electrical contacts, particularly the switch contacts, whereby increasing resistance in the battery circuit to a point where the flashlight bulb produces diminished illumination or even no illumination at all. This condition is aggrevated in cases where moisture can enter into the interior of the flashlight causing corrosion and therefore abnormal electrical resistance of the switch contacts and other contacts in the battery circuit.
SUMMARY OF THE INVENTION
It therefore becomes a principal object of the present invention to provide a flashlight having means for removing oxidation, dirt or the like from the switch contacts.
Another object is to provide a flashlight having a hermetically sealed interior.
Another object is to provide a flashlight having a readily removable and replaceable switch assembly.
Another object is to provide a hermetically sealed flashlight having an improved means for changing the focus of the light thereof between a narrow beam and a broad beam.
A further object is to provide a rugged and durable flashlight which will withstand extreme handling and abuse.
According to the present invention, a portable battery operable flashlight is provided having a rotary switch contact which is rotated relative to mating stationary contacts each time the switch is actuated whereby to rub or wipe off any dirt and products of oxidation or corrosion between the contacts. Moisture excluding elastomeric seals are provided between separable and movable parts of the flashlight to hermetically seal against intrusion of moisture and dirt.
According to another aspect of the invention, a focusable light reflector is provided which is axially movable relative to the bulb of the flashlight. The reflector is carried by a head member which is screw threaded on the flashlight casing. An elastomeric seal hermetically seals against entrance of moisture or dirt between the head member and the casing and also acts to frictionally lock the head member and the reflector in different adjusted positions. In a modified form, the head member carries a camming device which is capable, when the head member is rotated through less than one revolution, of fully adjusting the bulb axially to change the light from a narrow or spot beam to a broad or flood beam and vice versa.
Due to its rugged construction, the flashlight may be used by policemen as a billy club without damage thereto.
BRIEF DESCRIPTION OF THE DRAWING
The manner in which the above and other objects of the invention are accomplished will be readily understood on reference to the following specification when read in conjunction with the accompanying drawing, wherein:
FIG. 1 is a longitudinal sectional view of the flashlight embodying a preferred form of the present invention.
FIG. 2 is a transverse sectional view, partly broken away, and taken along line 2--2 of FIG. 1.
FIG. 3 is an enlarged sectional view through the switch assembly and is taken along line 3--3 of FIG. 1.
FIG. 4 is a sectional plan view through the upper part of the switch assembly and is taken along the line 4--4 of FIG. 3.
FIG. 5 is a sectional plan view taken through the lower part of the switch assembly and is taken along the line 5--5 of FIG. 3.
FIG. 6 is a sectional detail view of the switch guide body and the drive plunger for the indexing member.
FIG. 7 is a detailed sectional view of the indexing member.
FIG. 8 is a developed view showing the interior of the switch guide body, partly broken away.
FIG. 9 is a perspective view of one of the resilient pads for supporting an extra bulb in the flashlight casing.
FIG. 10 is an enlarged longitudinal sectional view through the head portion of a modified form of my invention.
FIG. 11 is a transverse sectional view, partly broken away, and taken along line 11--11 of FIG. 10.
FIG. 12 is a fragmentary plan view taken in the direction of the arrow 12 in FIG. 10.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawing, the flashlight is generally indicated at 11 and comprises a tubular casing 12, preferably of aluminum, and having a length to contain a selected number of batteries, i.e. 13, 14 and 15. That is, the casing 12 may be made in different lengths to receive a desired number of batteries, ranging from two to seven or more.
The casing 12 is counterbored at 16 to receive a switch housing 17 comprising nested upper and lower semi-cylindrical housing parts 18 and 20, respectively, preferably of a plastic having relatively high dielectric qualities. A groove 21, FIG. 2, in the upper housing part 18 receives a tongue 22 on the lower housing part 20 to clamp a pair of longitudinally aligned, spaced conductor strips 23 and 24 therebetween. The strips 23 and 24 are preferably of copper.
The housing part 20 is locked in properly oriented position in the casing 12 by a set screw 25 threaded therein and having a projection 26 extending into a mating socket formed in the wall of the casing 12. Also, a retainer ring 27 is screw threaded at 28 in the casing 12 and serves to clamp the switch housing 17 in place against the rear end of the counterbore 16.
A bulb holder 30, preferably of aluminum, is also screw threaded at 31 in the casing 12 and has a central bore 32 therein terminating in an inwardly extending flange 33 to receive the contact flange 34 of a light bulb or lamp 35. The latter is held in place against the flange 33 by a spring 36 compressed between the flange 34 and the switch housing 17 to establish a circuit connection between the base of the bulb 35 and the casing 12.
A metal contact plunger 37 is slidably mounted in a bore 38 formed in the upper and lower switch housing parts 18 and 20 and is yieldably held in engagement with a central contact 40 of the bulb 35 by a spring 41 compressed between the plunger 37 and a bent-over ear 42 on the forward end of the conductor strip 23 to establish a circuit connection between the bulb and the conductor strip 23. Contact 40 and flange 34 are electrically connected to opposite ends of the bulb filament 55.
A tubular head 43 is screw threaded over the casing 12 at 44 and carries a transparent window 45 of plastic or the like and a generally parabolic reflector 46. The latter elements are encased around their outer edges in an annular elastomeric seal 47 of U-shaped cross-section which is clamped between the head 43 and a face cap 48 screw threaded on the head at 50. The seal 47 prevents the entrance of moisture and dirt.
An O-ring 51 of elastomeric material is fitted within a groove 52 formed in the barrel casing 12 and frictionally engages a smooth bore section 53 formed in the head 43 to form a hermetic seal between the casing 12 and head 43. Such O-ring 51 also frictionally holds the head in any adjusted position on the casing 12.
It will be noted that the reflector 46 has a central opening 54 which is larger than the bulb 35 so that the head 43 may be screwed in or out relative to the casing 12 to move the reflector 46 axially relative to the bulb. Thus, as the focal point of the parabolic reflector 46 is moved forwardly of the bulb filament 55 the light beam becomes narrowed or concentrated for long distance observation or the like. On the other hand, when the focal point of the reflector is moved rearwardly of the bulb filament 55 the beam is broadened to provide a flood light pattern for lighting large areas, such as the interior of a room.
A tail cap 56, preferably of aluminum, is screw threaded at 57 in the rear end of the casing 12 and an O-ring 58 is clamped between the tail cap and the casing to form a hermetic seal at this juncture. A conical compression spring 60 is compressed between the cap 56 and the negative terminal of the rearmost battery 15 to yieldably hold the stack of batteries in electrical contact with each other and to maintain the positive terminal 59 of the foremost battery, i.e. 13, in electrical contact with a bent-over ear 61 on the conductor strip 24, thus establishing an electric circuit between the strip 24 and the casing 12.
The tail cap 56 is hollowed out at 62 to receive an extra bulb 63 which is sandwiched between two pads 64 and 65 of sponge rubber or the like to prevent breakage of the bulb in the event the flashlight should be dropped or struck a heavy blow. One such pad 64 is shown in FIG. 9.
It will be noted that the cap 56 presents an annular shoulder 59 which limits rearward axial movement of the batteries 13 to 15 in the event the flashlight is subjected to a shock or inertial load tending to drive the batteries rearward against the action of spring 60. Thus, the battery 15 can not crush the extra bulb 63, and the soft pads 64 and 65 prevent the bulb 63 from striking against the cap 56 or spring 60.
A flashlight switch is generally indicated at 66 (FIGS. 1 and 3) and comprises an annular switch guide body 67 (see also FIGS. 4 and 6), preferably of plastic, suitably removably secured as by an adhesive within a bore 68 formed in the upper switch housing part 18 in axial alignment with the set screw 25 and with an opening 89 in the casing 12. A hollow drive plunger 70 is slideable endwise in the body 67 and is provided with eight external splines 71 terminating in lower triangular end teeth 72. The splines are slideably endwise in interspersed grooves 73 and 73a (see also FIGS. 4 and 8) in the guide body 67. The bottoms of grooves 73 are coextensive with a cylindrical bore 69 formed in the lower end of the guide body 67 but the grooves 73a are shallower and terminate at their lower ends in inclined edges 75a. Interspersed between such grooves 73 and 73a are splines 74 terminating at their lower ends in inclined edges 75. As shown in FIG. 8, the inclined edges 75 of alternate splines 74 are coextensive with adjacent inclined edges 75a formed below the grooves 73a.
Normally, the plunger 70 is held in its upper illustrated position, wherein the upper ends of the splines 71 limit against a shoulder 76 on the guide body 67, by a compression spring 77 extending between the plunger and an indexing member 78 (see also FIG. 7). Member 78 has four equally spaced upwardly extending teeth 80 which are held in engagement with certain of the triangularly shaped teeth 72 on plunger 70, as seen in FIG. 3, by a spring 81 compressed between the member 78 and set screw 25. The upper ends of the teeth 80 are inclined in the same direction as the inclined edges 75 of the splines 74 and are also engageable with such edges 75 as will be described subsequently.
A disc shaped contact 82, preferably of brass, (see also FIG. 5) is slideably splined to the teeth 80 on indexing member 78 to permit vertical axial movement of the contact 82 relative to the indexing member 78 but constraining the contact to rotate with the indexing member. Normally, a spiral compression spring 83, interposed between the drive body 67 and the contact 82, and of less strength than spring 81, holds the contact against a shoulder 84 formed on member 78.
A bowl shaped flexible diaphragm 85 of rubber or similar elastomeric material is positioned in the opening 87 in casing 12 and is clamped along its outer edge between a flange 86 on the guide body 67, and a counterbored seat 88 formed in the upper switch housing part 18 to hermetically seal the switch against intrusion by moisture or dirt while permitting finger depression of the plunger 70 through the diaphragm to actuate the same.
An O-ring 90 of elastomeric material is fitted in a groove 91 formed in the switch housing part 18 and surrounding the switch guide body 67. The O-ring 90 hermetically seals against the inner periphery of the casing 12.
The switch 66 is illustrated in its open condition in which case the teeth 80 of index member 78 are located within aligned ones of the slots 73 (FIG. 8) as indicated by the dot-dash line representation 80a of one of such teeth. Thus, the indexing member 78 is allowed to be raised by spring 81 to its uppermost position shown in FIG. 3 wherein each of its teeth 80 engage a respective tooth 72 of plunger 70. Thus, the shoulder 84 of the index member 78 raises the contact disc 82 out of bridging engagement with the conductor strips 23 and 24 to hold the battery circuit open.
When the plunger 70 is depressed by finger pressure acting through the diaphragm 85, it likewise depresses the index member 78, causing the teeth 80 of the latter to slide downwardly along the respective grooves 73 until the contact disc 82 engages the conductor strips 23 and 24. Further depression of the plunger 70 against the action of spring 81 until the teeth 80 pass below the inclined edges 75 enables the teeth 72 to cam the teeth 80 and index member 78 to the right in FIG. 8 (left in FIG. 3) to move each tooth somewhat to the right of its position 80a. During this movement, the contact disc 82 is yieldably held in engagement with the conductor strips 23 and 24 by spring 83 and as it is partially rotated by the index member 78 it wipes or rubs against the strips to remove any products of oxidation or corrosion, leaving the contact surfaces clean to present a minimum resistance to the battery current. As the plunger 70 is released from finger pressure, it is returned to its upper position by spring 77 and index member 78 is forced upward by spring 81 causing teeth 80 to cam along the inclined edges 75 and 75a of the adjacent splines 74 until they reach their intermediate upper positions indicated by the dotted lines 80b in FIG. 8. Thus, the contact disc will be further rotated somewhat to rub against the conductor strips 23 and 24. When the teeth 80 come to rest in their intermediate positions, i.e. 80b against the inclined edges 75a, the contact disc 82 will still be held in bridging engagement with the conductor strips 23 and 24 by spring 83.
When the plunger 70 is again fully depressed, the index member 78 will again be depressed, and at the bottom of its stroke, the teeth 80 will again be partly rotated to the right in FIG. 8 so that when the plunger 70 is released they will cam along the inclined edges 75 of overlying splines 74 to move into the grooves 73 and thus permit the index member 78 to be moved fully upward into its position shown in FIG. 3, again carrying the contact disc 82 out of engagement with the conductor strips 23 and 24.
In the event it is desired to cause a rapid flashing of the light for signalling or similar purposes, the plunger 70 is repetitively depressed only part way, until the index member 78 carries the contact disc 82 into engagement with the conductor strips 23 and 24 but before the teeth 80 fully disengage from the grooves 73. Upon release of the plunger 70 the index member 78 will rise under the action of spring 81 to return the contact 82 upward to break the battery circuit.
Although a tungsten filament type bulb 35 is illustrated, the latter may be readily removed by completely unscrewing the head 43 and the bulb holder 30 and may be replaced by a bulb of the halogen type. Likewise, the batteries, i.e. 13, 14 and 15, may be readily removed by unscrewing the tail cap 56 and may be replaced by suitable batteries capable of energizing such halogen type bulb.
Due to the relatively high temperatures developed by halogen type bulbs, the housing parts 18 and 20 are preferably formed of heat resistant plastic.
The switch housing 17 may also be readily removed and replaced by suitably removing the switch assembly 66, including switch guide body 67 and then unscrewing the retainer nut 27 and then the set screw 25, permitting the housing parts 18 and 20 to be slid out through the forward end of the casing 12.
Since halogen type bulbs develop considerable heat, i.e. in the neighborhood of 400° F., and since the aluminum parts readily transfer such heat to the exterior, the flashlight can equally well be used as a hand warmer.
In view of the wiping action of the contact disc 82, the contact surfaces are always maintained clean and there is therefore no necessity of providing expensive non-oxidizing precious metals for such contacts.
DESCRIPTION OF THE ALTERNATE EMBODIMENT
FIGS. 10 to 12 illustrate a modified form of the head portion of the flashlight, such form facilitating adjustment of the flashlight to project either a narrow spot beam or a broad flood beam or any intermediate type beam by merely turning the head through one-half revolution or less.
Referring to the FIGS. 10 to 12, those parts which are similar to the parts found in FIGS. 1 to 9 will be identified by similar numerical reference characters.
A tubular head member 43a is screw threaded at 44a onto one end of the casing 11a and has a smooth bore section 53a which frictionally engages over an elastomeric O-ring 51a mounted in a groove in the casing 11a to hermetically seal the interior of the flashlight at that point and to yieldably hold the head 43a in any adjusted position.
A transparent window 45a and flanged rim 190 of a generally parabolic reflector 191 are clamped to the forward end of the head member 43a by an annular face clamp 48a which is screw threaded to the head member 43a at 50a. The annular clamp 48a clamps an elastomeric O-ring 92 against the window 45a to hermetically seal the window 45a.
A retainer ring 93 is screw threaded at 28a within the casing 11a to retain the switch housing 17a within the casing 11a. The ring 93 has a counterbore socket 94 therein to center and secure a guide sleeve 95 coaxially of the casing 11a. The sleeve 95 has a longitudinally extending guide slot 96 formed in the wall thereof (see also FIG. 12) to guide a cam follower roller 97 along the slot. The roller 97 is rotatably mounted on a bearing screw 98 which is threadably attached to a cylindrical bulb carrier sleeve 100 slidably mounted within the sleeve 95.
A light bulb 35a having a circular contact flange 34a is secured to the forward end of the sleeve 100 by a retainer cap 101 which is screw threaded over the sleeve 100 at 102 to clamp the flange 34a against the forward end of the sleeve 100.
A compression spring 103 is fitted within the sleeve 100 and is compressed between the base of the bulb 35a and the switch housing 17. One end 104 of the spring 103 extends radially outwardly to engage the interior of the casing 11a and thus establish an electrical contact between the casing 11a and the bulb 35a.
A guide sleeve 105 of plastic or the like insulating material is slidably fitted within the compression spring 103 and has a contact tip 106 of metal threadably attached thereto to engage a bent-over ear 42a of conductor strip 23a. A contact sleeve 107, also of plastic or like insulating material, is slidably fitted within the sleeve 105 and carries a metallic socket element 108 which is screw threaded thereto and which is held in electrical contact with the central contact 40a of the bulb 35a by a spring 110 which is compressed between the tip 106 and the socket element 108, the spring 110 forming the electrical connection between the tip 106 and the socket element 108.
A tubular or annular formation 111 is formed integrally with the rear end of the reflector 191 and extends concentrically over the guide sleeve 95. The formation 111 has an inclined end cam surface 112, against which the cam follower roller 97 is yieldably held by the spring 103. The reflector 191 has a central opening 113 therein through which the cap 101 and sleeve 100 may extend.
Accordingly, when the head member 43a is rotated in either direction from its full line illustrated position shown in FIGS. 10 and 12, the cam surface 112 will permit the spring 103 to move the lamp bulb 35a from its full line illustrated position where it projects a relatively narrow light beam of light to its dotted line position 35a' wherein it projects a relatively broad or flood beam of light. This whole traverse of the light bulb 35a to the opposite extremes of its travel is accomplished with only one-half revolution of the head member 43a. During such travel of the bulb 35a, the spring 110 expands and contracts, causing the sleeve 107 to slide lengthwise along the tube 105 to always maintain the bulb contact 40a in electrical connection with the conductor strip 23a as the bulb is moved back and forth.
It will be noted that the cam surface 112 is formed to generate a harmonic movement of the bulb 35a upon rotation of the member 43a in either direction from its position shown in FIGS. 10 and 12. However, such cam surface 112 may, if desired, be formed otherwise to generate other types of camming movement.
Although the head member 43a will partake of a slight axial movement during rotation thereof by virtue of its screw threaded connection 44a with the casing 11a, this will be of a minor consequence. On the other hand, in order to disassemble the flashlight, the head member 43a may be unthreaded completely from the casing 11a.
It will be obvious to those skilled in the art that many variations may be made in the exact construction shown without departing from the spirit and scope of this invention.
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A rugged, heavy duty flashlight which is hermetically sealed to prevent intrusion of moisture and dirt. A manually operable electric switch is provided having a rotary contact to complete the battery circuit to the bulb. When the switch is actuated the rotary contact is moved axially to engage stationary contacts and is then rotated to wipe against such stationary contacts to clean the contact surfaces. The flashlight is readily adjustable to change from a narrow concentrated light beam to a broad scattered beam.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional application of U.S. patent application Ser. No. 10/028,198, filed Dec. 20, 2001, which is incorporated herein in its entirety for all purposes.
BACKGROUND
[0002] This invention relates to precursors and methods for making thin films that are useful for the fabrication of integrated circuits (“IC”). In particular, this invention relates to thin films that are created by polymerizing fluorinated ethylinic precursors with fluorinated benzocyclobutane precursors, fluorinated biphenyl or fluorinated dieneone precursors. The resultant thin films have increased compositional strength, a low-dielectric constant (“ε”), and are stable at high temperatures.
[0003] As integrated circuits (“ICs”) have become progressively more microminiaturized to provide higher computing speeds, current dielectric materials used in the manufacturing of the ICs have proven to be inadequate in several ways. These materials, for instance, have high dielectric constants, difficulty to use in the manufacturing process, have inadequate thermal instability and generate of toxic by-products. ICs are made by depositing layers of elements and/or compounds on a semiconductor wafer using a variety of techniques that are well known in the art of fabricating such devices. Specialized material are used to isolate layers on the IC and reduce the charge (i.e. capacitance) that can be stored in between conducting elements of the IC. To reduce the potential capacitance in certain layers, it is preferable that the materials have a low dielectric constant (“ε”). Low dielectric constant materials can be deposited by a variety of methods, including spin-on and chemical vapor deposition (CVD). The composition and characteristics of the dielectric materials are determined from its precursors as well as the processes and reactions such precursors undergo while being integrated into the IC. As used herein, spin-on refers to the IC manufacturing process whereby the substrate is rotated about an axis perpendicular to its surface while, or immediately after, a coating material is applied to the surface. As ICs become smaller and more functional, a dielectric material with ε that is 2.7 or lower will be required.
[0004] Other properties such as thermal stability, compositional integrity and process compatibility are important factors that must be considered when integrating a dielectric material into an IC. For example, a dielectric material should retain its integrity during the processes involved in IC fabrication. These processes include reactive ion etching (“RIE”) or plasma patterning, wet chemical cleaning of photoresist, physical vapor depositions (“PVD”) of barrier materials and cap layers, electroplating and annealing of copper (“Cu”) and chemical-mechanical polishing (“CMP”) of copper. In addition, the dielectric should have sufficient dimensional stability. Interfacial stresses resulting from a coefficient of thermal expansion (“CTE”) mismatch between the dielectric and barrier material should not induce structural failure of the barrier material during and after annealing of copper. In addition, the interfacial adhesion of dielectric and the other barrier material should be sufficient to overcome interfacial and shear stresses and warrant good adhesion after annealing and CMP of copper. Corrosive organic elements used for IC processing can cause interfacial corrosion of the barrier material, and it is essential that the dielectric material does not allow the organic elements to diffuse into the barrier material layer. In addition, to maintain its electrical integrity after fabrication of the ICs, the dielectric should be free from contamination by the barrier material. Furthermore, the interfaces of dielectric and the barrier material should be free from moisture and no ionic migration occurs when the ICs are operating under electrical bias.
[0005] Dielectric materials that have been traditionally used in ICs were either solid or porous thin films. There are advantages and disadvantages to each. For example, the advantages of solid dielectric materials include: higher dimensional and structural integrity and better mechanical strength than porous dielectric materials, but the disadvantage is higher dielectric constant. In contrast, the advantage of porous dielectric materials is lower dielectric constant due to the presence of air inside tiny pores of these materials. Current solid materials are unable to achieve stability, integrity and strength with a dielectric constant below 2.7.
[0006] The “solid” polymer films or “pin-hole free” films contain voids that can generally range between 3 to 5 volume % of the films. However, the average void sizes in a cross-section of a well prepared “pin-hole free” or “solid” films are only few Angstroms. It is critical that the pore sizes of the thin films be relatively small in order to be useful for fabrication of current or future generation of ICs. For example, the pore sizes should be less than the mean free path (i.e. 50 to 100 Angstroms) of the barrier material, which is typically Tantalum (“Ta”).
[0007] The removal of solvents or sacrificing materials can result in additional porosity and low dielectric constant in “pin-hole free” polymer films. However, when the sacrificing materials have different compatibilities with the polymer matrix, the result can lead to polymer aggregation and pore sizes larger than 100 Angstroms. The resulting thin film dielectric has poor mechanical properties due to localized degradation caused by large pores or their aggregates. The presence of pores in theses dielectric materials normally results in holes oh newly formed surfaces, thus making subsequent depositions of a continuous, thin <50-100 Å) barrier layers and copper seed layers very difficult if not impossible. Additional problems with traditional porous thin films are they often exhibit reliability problems due to the inclusion of barrier metal inside the dielectric layer, as occurs after PVD of Ta. Porous dielectric materials are also difficult to integrate into IC fabrications that involve a CMP process. To further complicate the process, large surface areas in porous films lead to high water adsorption that can limit the electrical reliability of the IC.
[0008] Precursors such as Bicyclobutene (“BCB”) can be used to make thin films in a copper dual damascene structure without the need for a barrier layer such as Ta, however, the dielectric constant of BCB is greater than 2.7. Introduction of air bubbles into the BCB during the process can increases porosity and a consequential decrease of the dielectric constant. At 20% porosity, BCB has a dielectric constant of about 2.3. Unfortunately, the porous BCB and other dielectric materials that can achieve a ε≦2.4 are too soft for CMP and not suitable for fabrication of current and future ICs.
[0009] Plasma polymerization of fluorinated precursor molecules has also been described. For example, Kudo et al., Proc. 3d Int. DUMIC Conference, 85-92 (1997) disclosed polymers made from C 4 F 8 and C 2 H 2 with a dielectric constant of 2.4. The polymers had a glass transition temperature (“Tg”) of 450° C. However, despite its low leakage current due to presence of sp 3 C—F bonds, a low thermal stability occurred due to presence of sp 3 C—F and sp 3 C-sp 3 -C bonds in the films. Thus, these fluorinated polymers are unable to withstand the prolonged high temperatures necessary for IC manufacture. In addition, LaBelle et al, Proc, 3d Int. DUMIC Conference, 98-105 (1997) also described the use of CF 3 —CF(O)—CF 2 precursors in a pulsed plasma CVD process, which resulted in some polymer films with a dielectric constant of 1.95. However, in spite of the low dielectric constant, these polymer films also had a low thermal stability due to presence of sp 3 C-sp 3 C and sp 3 C—F bonds in these films.
[0010] Other fluorinated compounds described by Wary et al, (Semiconductor International, June 1996, 211-216) used the dimer precursor, (α, α, α 1 , α 1 ), tetrafluoro-di-p-xylylene (i.e. {—CF 2 —C 6 H 4 —CF 2 —} 2 ) and a thermal CVD process to manufacture Parylene AF-4™, which has the structural formula: {—CF 2 —C 6 H 4 —CF 2 —} n . Films made from Parylene AF44™ have a dielectric constant of 2.28 and have increased thermal stability compared to the above-mentioned dielectric materials. Films made of Parylene AF-4™ lost only 0.8% of its weight over a 3-hour period at 450° C. under a nitrogen atmosphere. However, there are disadvantages to the known methods the manufacture of the fluorinated poly (para-xylylenes), or Parylene AF44™. First, the manufacture of their precursors is inefficient because the chemical reactions have low yields, and the process is expensive and produces toxic byproducts. Further, it is difficult to eliminate redimerization of the reactive intermediates. When deposited along with polymers, these dimers decrease the thermal stability and mechanical strength of the film.
[0011] In our co-pending applications, we have disclosed some pin-hole-free polymer dielectric that can be prepared from transport polymerization process. These dielectric materials consist of sp 2 C—F and hyperconjugated sp 3 C—F in their polymer chains, thus they have ε≦2.4, and they are thermally stable for fabrication of future ICs. Herein, we describe precursors and processes for making thin films from precursors that results in polymers with low dielectric constant, improved compositional strength and high temperature stability that should provide low cost alternatives for fabrication of miniaturized ICs.
SUMMARY
[0012] The present invention includes the polymerization of precursors for production of a dielectric thin film with physical properties that overcome the disadvantages of prior art. In particular, this invention relates to thin films that are created by polymerizing fluorinated ethylinic precursors with fluorinated benzocyclobutane, fluorinated biphenyl or fluorinated dieneone precursors. The resultant thin films have increased dimensional stability, a low-dielectric constant (“ε”), and are stable at high temperatures. The thin films described herein can be incorporated into the manufacturing process of integrated circuits, active matrix liquid crystal display or fiber optic devices. In addition to the disclosure of the precursors for the dielectric thin films, a spin-on method for producing dielectric thin films in the manufacturing process is also discussed. Other objects, aspects and advantages of the invention can be ascertained from the review of the detailed disclosure, of the examples, the figures and the claims.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0013] This invention discloses thin fluorinated films with low dielectric constants (“ε”) that are useful in the manufacture of integrated circuits and other electronic devices. Manufacture of smaller and faster integrated circuits requires inter-metal dielectric (IMD) and inter-level dielectric (ILD) materials that minimize the communication of electrical signals between adjacent conductive lines, referred to as the interconnects. Low dielectric constant materials are useful to minimize “crosstalk” within and between layers of integrated circuits in addition to serve many other purposes.
[0014] The polymers prepared from the precursors of the present invention contain a high degree of substitution of hydrogen atoms by fluorine atoms. In these polymers, the fluorine in the aromatic ring provides the low dielectric constant below about 2.6 and molecular rigidity. This rigidity is reflected by high glass transition temperature (Tg), high elastic modulus (E) and high shear modulus (G). Their elastic modulus is above about 2.5, and mostly is above 3.5 GPa.
[0015] Films made from Parylene AF44™ have a dielectric constant of 2.28 and have increased thermal stability compared many different dielectric materials. However, there are disadvantages to the known methods the manufacture of Parylene AF44™. Despite these disadvantages, it is important to understand the advantages of such polymer in order to produce the next generations of thin films. Although not wanting to be bound by theory, the thermal stability of the Parylene AF44™ is due to the higher bonding energies of the sp 2 C=sp 2 C, sp 2 C—H and sp 2 C-sp 3 C bonds of 145, 111 and 102 kcal/mol respectively. In addition, the sp 3 C—F bonds may also be involved in hyperconjugation with sp 2 C=sp 2 C double bonds of the adjacent phenylene groups in Parylene AF44™. This hyperconjugation renders a higher bond energy for the sp 3 C—F bonds than are found in non-hyperconjugated sp 3 C—F bonds.
[0016] Thus, polymers consist of sp 2 C=sp 2 C, sp 2 C—F and hyperconjugated sp 3 C—F bonds confer advantages, whereas other types of bonds (such as sp 3 C—F and sp 3 C—H bonds) do not confer these advantages. The sp 2 C=sp 2 C and other sp 2 C bonds increase the mechanical strength and increase Td (Decomposition Temperature) of the polymers. The fluorine atoms on the aromatic moieties of the polymers of this invention decrease the dielectric constant and the sp 2 C—F and hyperconjugated sp 3 C—F bonds confer greater thermal stability to these polymers. In contrast, polymers that do not contain these types of bonds have lower thermal stability and higher dielectric constant.
[0017] One embodiment of the present invention pertains to fluorinated precursors and processes for making thin polymer films that have low-dielectric constant and have improved dimensional stability, and are stable at high temperatures. In particular, this invention relates to novel fluorinated precursors and the methods to process these fluorinated precursors. These polymers have a dielectric constant ε equal to or less than 2.7, thus are useful in the fabrications of ICs. The present invention preferably uses the spin on method to dispense the fluorinated precursors onto the wafer.
[0018] Broadly, one aspect of the present invention pertains to a thin film with a low dielectric constant by co-polymerization of an ethylenic-containing precursor (Ia) with a benzocyclobutane (IIa′)-, a biphenyl (IIb′)- or a dieneone (IIc′)-containing precursor, or their admixture. The ethylenic-containing precursor (Ia) can have the following general structure:
P-(-Z-W) n° (Ia)
[0019] wherein, W is —H, —F or fluorinated phenyl; n° is an integer of 2, and Z is a moiety containing an ethylenic (C≡C) group.
[0020] P can be —C 6 H 4-n F n -(n=0 to 4); —C 6 H 4-n F n —CF 2 —C 6 H 4-n F-(n=0 to 4); —C 10 H 6-n F n -(n=0 to 6), or —C 12 H 8-n F n -(n=0 to 8).
[0021] The benzocyclobutane-containing precursor can have the following general structure (IIa′):
[0022] wherein W′, W″, W′″, W″″, W′″″, and W″″″ are independently the same or different and are fluorinate phenyl, —F or —H, n′ is an integer of 2. P′ can be —C 6 H 4-n F n -(n=0 to 4); —C 6 H 4-n F n —CF 2 —C 6 H 4-n F n -(n=0 to 4); —C 10 H 6-n F n -(n=0 to 6), or —C 12 H 8-n F n -(n=0 to 8).
[0023] The diphenyl containing precursors can have the following general structures (IIb′):
[0024] wherein each W is fluorinate phenyl, —F or —H, n′ is an integer of at least 2 to a number that is less than total sp 2 C substitutions on P′. P′ can be —C 6 H 4-n F n -(n=0 to 4); —C 6 H 4-n F n —CF 2 —C 6 H 4-n F n -(n=0 to 8); —C 10 H 6-n F n -(n=0 to 6), or —C 12 H 8-n F n -(n=0 to 8).
[0025] The dieoneone-containing precursors can have the following general structures (IIc′):
[0026] wherein each W is fluorinate phenyl, —F or —H, n′″ is an integer of at least 2 to a number that is less than total sp 2 C substitutions on P′. P′ can be —C 6 H 4-n F n -(n=0 to 4); —C 6 H 4-n F n —CF 2 —C 6 H 4-n F n -(n=0 to 8); —C 10 H 6-n F n -(n=0 to 6), or —C 12 H 8-n F n -(n=0 to 8).
[0027] Pinhole-free thin films can be prepared by the following steps:
[0028] Precursor molecules, such as ethylenic (Ia) with benzocyclobutane (IIa′), biphenyl (IIb′), or dieneone (IIc′), or their mixture are first dissolved or suspended in an appropriate solvent. This mixture or suspension is then dispensed onto the surface of interest by the spin-on technique, which results in a thin wet film. The thin wet film is then heated at 3 to 5° C. per minute to a predefined maximum temperature, T max . Thus, the wet film is heated from 5 to 50° C. below the boiling point of the solvent. The resultant film is then heated at 10° C. per minute to a maximum temperature, T max that ranges from 10 to 20° below the glass transition temperature (“Tg”) of the thin film. A thin film according to this invention has a dielectric constant of less than 2.6, preferably less than 2.4. Thus, thin film derived from polymerization of precursors (IIa′, IIb′ or/and IIc′) with precursor (Ia) are useful for the manufacture of ICs, active matrix LCDs or a fiber optic device. In addition, this invention will provide thin films that are compatible with the Dual Damascene process used in manufacturing of future ICs.
[0029] The heating and curing processes described in the above should preferably conducted under non-oxidative, inert conditions to prevent oxidation of prepolymers. Ideally, the processes should be conducted under nitrogen or vacuum condition on hot plate and inside an oven. The final heating or curing process should be at least 5 to 10 minutes if conducted on a hot plate, and should be at least 20 to 30 minutes if conducted inside an oven. The final cure temperature should be at least reaching to 5 to 10° C. below its maximum achievable Tg, Tg(max). From a practical point of view, Tg(max) is defined here for the Tg that can be obtained by heating the dielectric inside a sample cell in DSC (Differential Scanning Calorimeter) to 450° C. at 10° C. per minute heating rate under nitrogen atmosphere. The Tg(max) can be obtained by re-scanning the dielectric material inside the sample cell under the same conditions.
[0030] Set forth in the following illustrations are polymerization reactions useful to create the low ε thin films from the above precursors (Ia with IIa′, IIb′ and IIc′) of this invention:
[0031] wherein, n″″ is an integer of at least 10, preferably 20.
[0032] P and P′ can be the same for each of the above reactions. P and P′ is independently an aromatic moiety, preferably a fluorinated aromatic moiety, containing compound. The aromatic moiety includes, but is not limited to:
[0033] —C 6 H 4-n F n -(n=0 to 4), such as —C 6 H 4 — and —C 6 F 4 —; —C 6 H 4-n F n —CF 2 —C 6 H 4-n F n -(n=0 to 4); napthyenyl moiety, —C 10 H 6-n F n -(n=0 to 6), such as —C 10 H 6 — and —C 10 F 6 —; di-phenyl moiety, —C 12 H 8-n F n -(n=0 to 8), such as —C 6 H 2 F 2 —C 6 H 2 F 2 — and —C 6 F 4 —C 6 H 4 —; anthracenyl moiety, —C 12 H 8-n F n —; phenanthrenyl moiety, —C 14 H 8-n F n —; pyrenyl moiety, —C 16 H 8-n F n — and more complex combinations of the phenyl and naphthenyl moieties, —C 16 H 10-n F n —. The aromatic moieties could include isomers of various F substitutions and reaction groups (X,Y,Ar′ & D).
[0034] Thus, P and P′ can be an aromatic moiety-containing compounds of the following general structures:
[0035] —Ar-L-AR′-, wherein Ar and Ar′ is selected from P or P′. L is a linkage unit such as —O—CH 2 —O—, —O—CF 2 —O—, —Si(R) 2 —O—Si(R) 2 , —O—, —CO—, —SO 2 —, or —O—Ar—O— groups, and is preferably a —CF 2 — group. R can be an aromatic radical, an alkyl radical, —CH 3 , or preferably a —CF 3 .
[0036] Compounds P and P′, by definition, can be simple organic compounds, oligomers or polymers. An oligomer is a molecule consisting of many (2 to 10) repeating units in its backbone structure whereas a polymer is a macromolecule consisting of more than 10 to 20 repeating units in its backbone structure.
[0037] X in the above compound (I) is an acetylenyl radical, such as —C≡C—W, wherein W is a fluorinate phenyl, —H or —F. (Note that in (Ia), -Z-W equals to-X and n=2 in (I)).
[0038] Y in the above compound (IIa) is a benzocyclobutane radical of the following structure (IV):
[0039] wherein each W is a fluorinate phenyl, —F or —H.
[0040] Ar′ in (IIb) is a biphenyl radical of the following structure (V):
[0041] wherein each W is a fluorinate phenyl, —H or —F.
[0042] D in the above compound (IIC) is a dieneone radical of the following structure
[0043] wherein each W is a fluorinate phenyl, —H or —F.
[0044] According to the above reactions, Z is the repeating chemical structure of the following structure (VII) for the reaction (1):
[0045] Z′ is (VIII) for the reaction (2):
[0046] Z″ is (IX) for the reaction (3).
[0047] The disclosed invention also includes precursors (Ia′, IIa′, IIb′ and IIc′) consisting of more than two functional groups (X, Y, Ar′ and D in I, IIa, IIb and IIc; when n°, n′, n″, or n′″ is greater than 2). When precursors consisting of more than two functional groups are used in preparations of thin films, it is desirable to balance the total number of functional groups in (Ia, n°>2) with that of (IIa′, IIb′ or IIc′; n′, n″, or n′″ is greater than 2). Although not wanting to be bound by theory, the ratio of the total number of functional groups in (Ia) to that in (II) should be in the range from 0.85 to 1.20, preferably between 0.9 to 1.1. In these cases, better cross-linked polymer thin films will result.
[0048] In order to achieve a dielectric constant of 2.7 or lower, the above referenced precursors should consist of a sufficient amount of F substitution to H in their sp 2 C—H and sp 3 C—H bonds. Further, in order to achieve thermal stability and higher rigidity, the above referenced precursors should consist of a substantial amount of F substitution to H in their sp 3 C—H bonds. In general, all sp 3 C—H should be replaced with F in order to achieve the thermal stability required in IC fabrication. The immediately foregoing does not apply to precursors that include a sp 3 C α —H bond, wherein C α is an alpha carbon connecting to an aromatic group. According to hyper-conjugation principle, the sp 3 C α —H bond is substantially more thermally stable than that of a sp 3 C—H bond. However, to achieve a dielectric constant ε<2.4, the total amount of F substitution to H can be estimated as follows.
[0049] It is known that without any F substitution to H for the above precursors (Ia) and (IIa′, IIb′ and IIc′), the resulting dielectric will have a constant ε of about 2.65 to 2.75. However, when each C—H bond is replaced with C—F bond, the constant ε of the resulting polymer will be lowered at 0.05 to 0.07 per substitution with a limiting lowest ε of about 1.9. Therefore, the ratio of (sp 2 C—F+sp 3 C—F)/(sp 2 C—F+sp 3 C—F+sp 2 C—H+sp 3 C—H) of resulting thin films should be at least 0.4, preferably 0.7.
[0050] To make thin films from the above referenced precursors (I and IIa, IIb and IIc), in general, such precursors are spin coated onto the wafer. The wet film is then conditioned under slow heating rates (3 to 5° C./minute) to remove most (80 to 90%) of the solvent(s). The resulting dry films are then exposed to polymerization conditions that normally have various time-temperature-heating rate schedules.
[0051] Under proper processing conditions, solid, “pinhole-free” thin films useful for fabrication of ICs can be obtained for polymers (IIIa and IIIb). To obtain “pinhole-free” thin films, solvent-drying temperatures are generally need to be at least 20 to 50° C. below the boiling temperature of the solvent. In addition, it is desirable to heat the wet film under an inert gas such as nitrogen. Polymerization can then be carried out by heating the resulting wet films slowly from (Tb-20 to 50) to (Tg-T) ° C. Wherein, Tg is the attainable glass transition temperature for a given polymer and T ranges from 20 to 50° C. Preferably, (Tg-T) preferably should not exceed 450° C. When (Tg-T) approaches 400 to 450° C., the heating time should be less than 30 to 60 minutes under such temperatures. During polymerization, the heating rate normally ranges from 20 to 30° C./minute depending on the thickness of the films. For making thin films (<1-2 μm), heating rate can be as high as 40 to 50° C./minute.
[0052] A more restrictive and controlled drying and cure procedure is necessary to obtain “pinhole-free” thin films for polymer IIIc. Due to the generation of carbon monoxide during polymerization, thin films of various porosity and pore sizes may result. For example, as noted herein, if the polymerization is carried out for a very dry film under a slow heating rate (5 to 10° C./minute), “pinhole free” thin film can be obtained. However, if polymerization reactions are carried out at temperatures that are higher than the soft temperatures of polymer chains inside the wet films, thin films with porosity will result. Therefore, in principle, thin films with various porosity and pore sizes can be obtained by manipulating the polymerization conditions or weight % of a solvent in a given film. Generally, pore size distribution is uniform, since it is controlled from polymerization reactions that only occur at chain ends. This is different from other conventional methods that used co-solvents or low thermally stable inclusions (or sacrificing materials) to generate porous dielectrics.
[0053] The invention includes novel precursors containing a fluorinated aromatic moiety. The precursors are suitable for making thin films with low dielectric constants and high thermal stability. Additionally, the invention includes methods for applying thin films of this invention for various electronic devices. Therefore, integrated circuits, liquid crystal displays or fiber optic devices consist of these thin films should have improved electrical and mechanical performances.
[0054] It should be appreciated by those of ordinary skill in the art that other embodiments may incorporate the concepts, methods, precursors, polymers, films, and devices of the above description and examples. The description and examples contained herein are not intended to limit the scope of the invention, but are included for illustration purposes only. It is to be understood that other embodiments of the invention can be developed and fall within the spirit and scope of the invention and claims.
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New precursors and processes are disclosed for making fluorinated, low dielectric constant ε thin films that have higher dimensional stability and are more rigid than fluorinated poly (para-xylylenes). The fluorinated, low dielectric constant thin films can be prepared from reactions of an ethylenic-containing precursor with benzocyclobutane-, biphenyl- and/or dieneone-containing precursors. The fluorinated, low dielectric constant thin films are useful for fabrications of future <0.13 μm integrated circuits (ICs). Using fluorinated, low-dielectric constant thin films prepared according to this invention, the integrity of the dielectric, copper (Cu) and barrier metals, such as Ta, can be kept intact; therefore improving the reliability of the IC.
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CROSS-REFERENCE TO RELATED APPLICATION
The present application is a continuation-in-part of my previous application Ser. No. 789,954 filed Jan. 8, 1969, and now abandoned.
SUMMARY OF THE INVENTION
This invention relates to new compounds of the structure ##STR2## WHERE R is an aromatic group, an alicyclic group or an open chain saturated aliphatic group of at least 8 C atoms, x is an integer of from 1 to 9, R' is H, a lower alkyl group of from 1 to 4 C atoms, or a lower haloalkyl group of from 1 to 4 C atoms, Y is an integer of from 0 to 10 and z is an integer of from 2 to 6, and to methods of preparing the new compounds by dehydrohalogenating the corresponding halohydrin with a hydrogen halide acceptor or by reacting the polythiol with an unsaturated monoepoxide.
Polyglycidyl ethers having a functionality of two or more are difficult to obtain. They usually have been made by reacting a polyalkylene glycol with epichlorohydrin and subsequently ring closing. The reaction between the hydroxyl group of the polyalkylene glycol and epichlorohydrin is usually only partially complete, so that a relatively high proportion of monoepoxy product results.
One of the advantages of this invention is that polyepoxide formation is essentially complete. Another advantage is the average number of epoxide groups can be controlled so that from 2 to 4 such groups can be obtained per molecule. Another advantage is that the physical properties of the final polyepoxide can be varied over a wide range by controlling the values of x, y and the R and R' groups in the generic formula. Another advantage is that the final polyepoxides have structures which are stable to hydrolysis under either acid or alkaline conditions and the most reactive portions of the molecule are the epoxide groups. A further advantage is that the polythioether polyepoxides are of low viscosity and are therefore useful as reactive diluents for polyepoxides such as the diglycidyl ethers of bisphenol A or the glycidyl ethers of phenol-formaldehyde novalacs such as DEN-431 or 438 (products of The Dow Chemical Co.). When copolymerized with these epoxides, tough, impact-resistant polymers are obtained.
DETAILED DESCRIPTION OF THE INVENTION
The precursor halohydrins, used for making the polythioetherpolyepoxides of this invention are prepared by reacting a polymercaptan (i.e. any mercaptan having 2 or more --SH groups) with an olefinically unsaturated ether halohydrin, preferably terminally monoolefinically unsaturated, to thereby form an adduct in which at least two of the --SH groups on the polymercaptan will each add across an olefinically unsaturated portion of the ether halohydrin. The product resulting from such addition will contain at least two halohydrin groups in which the halogen and OH groups are vicinal to each other on individual carbon chains.
Representative halohydrins include: 1-allyloxy-3-chloro-2-propanol, 1-(10-undecenyl)oxy-3-chloro-2-propanol, 1-(2-allyloxy)ethoxy-3-chloro-2-propanol, ##STR3##
Representative olefinically unsaturated monoepoxides which can be reacted with the polythiols include: allyl glycidyl ether, (2-allyloxy)ethyl glycidyl ether, 4-butenyl glycidyl ether, ##STR4##
The polythiol can be an aliphatic, oxaalkyl, polyoxaalkyl, thiaalkyl or polythiaalkyl group containing from 2 to 12 carbon atoms, with the provision that the thiol groups are separated by at least two carbon atoms. Examples of suitable polythiols include 1,2-ethanedithiol, 1,3-propanedithiol, bis(2-mercaptoethyl)ether, bis(2-mercaptoethyl)sulfide, 1,8-dimercapto-3,6-dithiaoctane, 1,11-dimercapto-3,9-dithia-6-oxaundecane, bis(3-mercaptopropyl)ether, or 1,8-dimercaptooctane.
The polythiol may be a cycloaliphatic polythiol containing from 6-12 carbon atoms. Suitable polythiols include ethylcyclohexyl dimercaptan (the reaction product of 4-vinylcyclohexene with hydrogen sulfide), dipentene dimercaptan, 1,4-dimercaptocyclohexane, or 1,2,4-tris(2-mercaptoethyl)cyclohexane.
Suitable aryl or aralkyl polythiols include α,α'-dimercapto-p-xylene, 1,3-benzenedithiol, o,p,p'-tris(mercaptomethyl)diphenyl ether.
A final class of polythiols which can be employed are disclosed in my application entitled "Polyetherpolythiols, Method of Preparation and Mixtures of Polythioetherpolythiols with Epoxide Resins", Ser. No. 771,648, filed Oct. 29, 1968, and now abandoned. Typical polyetherpolythiols can be prepared by reacting 1,2-ethanedithiol with a trivinyl cyclohexane, a representative of which is 1,2,4-trivinylcyclohexane; 1,2-ethanedithiol with 1-allyloxy-2-allylbenzene or other allyloxy allylbenzenes; 1,3-propanedithiol with 1-allyloxy-2,6-diallylbenzene or isomers thereof; 1,2-propanedithiol with the triallyl ether of glycerol or 1,2-ethanedithiol with a polyallyl ether of pentaerythritol containing about 3-4 allyl groups and particularly about 3.5 allyl groups.
The proportions of reactants should be such that at least one thiol group is available for each unsaturated carbon to carbon bond. Preferably the unsaturated compound is added to a mixture of the polythiol and catalyst.
The reaction of the dithiol with a compound having 3 to 5 olefinically unsaturated linkages or a mixture of at least one of said compounds with a diolefinically unsaturated compound is preferably carried out in the presence of a free-radical initiating catalyst such as organic peroxides or hydroperoxides, examples of which are benzoyl peroxide or t-butyl hydroperoxide, the azonitriles, such as azoisobutyronitrile, ultra-violet light or a cobalt 60 source of gamma radiation. The resulting polythioether polythiols have a thiol functionality greater than 2.05 and usually 2.2 to 4. Thus, the R of the generic formula can be an alkylene group of from 2 to 12 C atoms, an alkylene ether group of 4-12 C atoms, an alkylene thioether group of 4-12 C atoms, an alkylene ether-alkylene thioether group of from 6 to 18 C atoms, a polyalkylene ether or polyalkylenethioether group of 6-18 C atoms, an aromatic hydrocarbon group containing 1-3 rings, an alkylene aromatic group having from 1 to 4 alkylene or oxaalkylene groups each containing 1 to 4 C atoms, polyalkylene diphenyl oxide groups having 2 to 4 alkylene groups of from 1 to 4 C atoms, and the reaction products of a dithiol and a poly-unsaturated compound having at least three carbon to carbon double bonds and mixtures thereof with a diene. These reaction products can contain up to about 50 C atoms.
Catalysis can be effected by any known free radical catalysts which form free radicals at temperatures of 25° to 150°. Also, actinic free radical formers such as U.V. light or gamma rays can be used as catalysts. Typical catalysts include: azobisisobutyronitrile, ditertiarybutyl peroxide, t-butylhydroperoxide, methyl ethyl ketone peroxide, 1-azocyclohexane carbonitrile, t-butyl perbenzoate, benzoyl peroxide and the like.
The reaction can be carried out at a temperature of 25° to about 125° with the unsaturated epoxides and 25° to 150° with the unsaturated halohydrins. Dehydrohalogenation of the halohydrins can be effected with any hydrohalide acceptor such as any of the alkali metal hydroxides preferably NaOH or KOH, or the corresponding carbonates or bicarbonates or tertiary amines such as trimethyl, triethyl or tripropyl amines, or any quaternary ammonium hydroxide. The alkaline alkali metal compounds can be solids or in solution.
Pressure has no effect on the reaction, so that it can be run at atmospheric, superimposed or subatmospheric pressure. Preferred is the autogenous pressure at the reaction temperature employed.
The examples below are intended to illustrate, but not to limit, the invention. In all instances parts are given by weight unless otherwise indicated.
EXAMPLE I
A polythioetherpolythiol was prepared by adding 81.2 g. of 1,2,4-trivinylcyclohexane over a 11/2 hour period to 283 g. of 1,2-ethanedithiol containing 1 g. of azoisobutyronitrile. The mixture was stirred for an additional 4 hours. A temperature of 70° C was maintained during the entire period. Unreacted 1,2-ethanedithiol was removed by distillation at a pressure of 0.5 mm. A yield of 201 g. of a polythioetherpolythiol having a viscosity of 1300 cps. was recovered. The polythioetherpolythiol analyzed 40.9% by weight total sulfur and 16.9% as SH.
The reaction mixture contained an appreciable amount of the triadduct ##STR5##
A solution of 112 g. of the above polythioetherpolythiol and 1 g. of azoisobutyronitrile in a 500 ml. flask was heated to 70° C and 240 g. of allyl glycidyl ether were added dropwise during a two hour period. The mixture was then heated at 70° C for an additional 7 hours. Unreacted allyl glycidyl ether was removed by distilling to 70° at 1.0 mm., leaving 187 g. of a yellow epoxide having a viscosity of about 1300 cps. and an epoxide equivalent weight of 292. An infrared spectrum showed that hydroxyl and olefinically unsaturated groups were absent.
EXAMPLE II
A series of runs was made using polythioetherpolythiols, which were made by reacting 1,2-ethane dithiol with 1 allyloxy-2,6-diallyl benzene, 1-allyloxy-2-allyl benzene, a mixture containing 50/50 mol percent of the diallyl ether of bisphenol A and triallyloxy propane. The polyepoxide in each case was prepared by placing the polythioetherpolythiol in a 50 ml. high silica glass tube and adding allyl glycidyl ether dropwise. The mixture was irradiated with a UA-2 lamp during the entire run of 2 hours each. The reaction was effected while bubbling a stream of nitrogen through the mixture. Tablulated below are the data from the several runs. In the table AGE means allyl glycidyl ether.
TABLE I__________________________________________________________________________Polythiol Prepared From: SHRun HSCH.sub.2 CH.sub.2 SH/ eq. g. Poly- g. g. Pro- EpoxideNo. Olefin Olefin Ratio wt. thiol AGE duct Viscosity eq.__________________________________________________________________________ wt. ##STR6## 6 moles/1.0 mole 206 20.6 11.4 30 10.7 poises 362.32 ##STR7## 5.0 moles/1.25 moles 197 19.7 11.4 30.4 ˜1.85 326.43 ##STR8## 5 moles/1.0 mole 228 22.8 11.4 33 ˜3.30 362.34 ##STR9## 4 moles/0.66 mole 231 23.1 11.4 33.2 391.4__________________________________________________________________________ The polyepoxide was prepared by placing the polythiol in a 50 ml. Vycor tube and adding the AGE portionwise. The mixture was then irradiated with a UA-2 lamp under a stream of N.sub.2 for 8 hours.
EXAMPLE III
A mixture of 4 g. azobisisobutyronitrile and 150 g. of 1-allyloxy-3-chloro-2-propanol was heated to 70°-73° C while adding 59 g. of 2,2'-bis(mercaptoethyl) ether. After a few hours post reaction, the product was cooled to room temperature. Then 50 g. of NaOH pellets were added while maintaining the temperature below 40° C. The mixture was stirred for 2 hours and then filtered to yield a yellow, free flowing polyepoxide.
This procedure was repeated with 77 g. of 2,2'-bis(mercaptoethyl)sulfide and 150 g. of 1-allyloxy-3-chloro-2-propanol, the mixture was diluted with 200 ml. benzene before adding the 50 g. of NaOH pellets. Stirring was continued for 5 hours after adding the NaOH. Sufficient water was added to the mixture to dissolve the NaCl and the benzene layer was separated from the aqueous layer. Evaporation of the solvent left a yellow fluid epoxide with an epoxide equivalent weight of 254.
EXAMPLE IV
Certain dithiols were reacted with unsaturated alkylene ether chlorohydrins. In each instance the dithiol was added to a chlorohydrin and was contained in a 600 ml. beaker and stirred with a magnetic stirrer. The contents were irradiated with a UV-2 ultra violet lamp for four hours. During the entire period the beaker was cooled with tap water. The molar ratio of the chlorohydrin to the dithiol was at least 2 to 1. After completion of the reaction sufficient solid NaOH was added to the mixture to convert the dihalohydrin to a diepoxide. It is to be understood that the main product formed in each instance was the diadduct of the unsaturated halohydrin to the dithiol.
Tablulated below are the list of products reacted and the epoxide equivalent weight of the diepoxide formed.
TABLE II__________________________________________________________________________Dithiol Chlorohydrin Epoxide eq. wt.__________________________________________________________________________ ##STR10## CH.sub.2CHCH.sub.2 OC.sub.2 H.sub.4 OCH.sub.2 CHOHCH.sub.2 487HS(CH.sub.2).sub.8 SH CH.sub.2CH(CH.sub.2).sub.9 OCH.sub.2 CHOHCH.sub.2 Cl 476__________________________________________________________________________
The polyepoxides of this invention are, in general, low to medium viscosity liquids which can be used as reactive diluents for bisphenol A type diepoxides.
The epoxides of this invention can be polymerized by strong bases or tertiary amines such as benzyldimethylamine, tetramethylguanidine, and the like. The epoxides are particularly useful as impact modifiers for bisphenol A based epoxies which are well known items of commerce.
Other polythioether polyepoxides of this invention can be blended with 10-30 to about 40% by weight of known liquid epoxide resins or novolacs and subsequently cured with nitrogen containing curing agents to provide solvent or impact resistant, flexible products.
To demonstrate the ability of the polyepoxidepolythioethers for improving the impact properties of commercially available bisphenol A based epoxide resin, several of the products of the examples were copolymerized with a liquid, diglycidyl ether resin of bisphenol A. The liquid resin had an epoxide equivalent weight of 172-178 and a viscosity at 25° C of 40-64 poise. One such resin is designated as DER R 332 by The Dow Chemical Company. A ten gram sample of each mixture described below was thoroughly blended with 0.5 gram of benzyldimethylamine and heated in an aluminum cup for 17 hours at 100° C.
______________________________________DER.sup.R 332% by Product of % byweight Example No. Weight______________________________________50 1 5070 II, Run 1 3070 II, Run 2 3070 II, Run 3 30100 -- --______________________________________
All the samples gave rigid solids which adhered well to the aluminum cup. When the sample containing the liquid resin of the diglycidyl ether of bisphenol A was struck with a hammer, it shattered into numerous pieces. The samples which contained the polyepoxide polythioethers of the examples withstood repeated pounding with the ball-peen of a hammer.
The remaining products of the generic formula ##STR11## when blended with the liquid resin of diglycidyl ethers of bisphenol A and copolymerized also form tough, shock resistant solid resins, which adhere well to aluminum and other metals.
The copolymers as above described, are useful for adhering metal to metal, metal to glass, metal to fibers, both cellulosic and the well-known synthetic fibers. They are also useful as solvent resistant flexible coatings for protecting metal sheet and formed articles.
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New compounds of the structure ##STR1## WHERE R is an aromatic, alicyclic or aliphatic group of at least 2 C atoms and up to 18 C atoms, x is an integer from 1 to 9, R' is H, a lower alkyl grup of 1-4 C atoms or --CH 2 Cl, y is an integer of from 0-10 and z is an integer of from 2 to 6 are prepared by reacting a polythioetherpolythiol with an olefinically unsaturated epoxide or by dehydrohalogenating the corresponding halohydrins. The new compounds are useful as diluents for epoxy resins to reduce their viscosity and to improve flexibility of the cured resins.
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TECHNICAL FIELD
[0001] The invention relates to natural duvet/pillow stuffing, which consists of down and feathers with silver particles.
BACKGROUND
[0002] It is well-known that silver has antibacterial properties and that the bacteria do not become resistant to silver. KR 20050016259 also describes adding silver particles to duck feathers for bedclothes in order to provide them with an antibacterial and sterilising effect.
DISCLOSURE OF THE INVENTION
[0003] The aspect of the invention is to provide a natural stuffing for duvets/pillows, said stuffing having a particularly good and stable sterilising effect.
DETAILED DESCRIPTION OF THE INVENTION
[0004] The new aspect of the invention is that the size of the silver particles is ≦5 nanometres.
[0005] By this, the natural stuffing is provided with a good, stable and enduring (for several years) antibacterial and sterilising effect and the original “feather smell” is removed together with the smell caused by micro-organisms. Particularly a pronounced smell from mould fungus is removed by this. In addition, the silver enhances the volume of the natural stuffing, in that the volume of the lowest feather qualities is enhanced with up to 10%. The positive charge of the silver ions affects the negative charge of the protein and thus limits static electricity. The silver particles are complete metallic particles and silver ions (Ag+). This size has a particularly good effect against bacteria, which are smaller than viral particles. The effect is enhanced in that silver ions with a size of ≦5 nm will cover a considerably larger surface area than silver ions with a size of e.g. 35 nm, as the former will cover an area of more than 460,000 times its volume, whereas the latter will cover an area of 175,000 times its volume. By this, the surface area for influencing the bacteria will be particularly large. The smaller the silver ions are, the more the fine down strings are prevented from collapsing. The colloid silver shape ensures an efficient distribution of the silver particles on the feathers during the washing process, and especially silver particles of the size in question have a particularly stable ability to maintain the distribution on and the adherence to the down and the feathers for a long time despite many washes, whereby the natural stuffing can maintain its volume without collapsing.
[0006] More particularly, it has been found that the silver particles inhibit the presence of Escherichia Coli., Streptococcus pneumoniae , yellow staphylococcus bacteria, and the development of Aspergillus mould fungus. By this, odour problems from bacteria are neutralised, and prevention and/or treatment of mild infections and mucous membrane problems is also observed.
[0007] A particularly preferred amount of silver is 1-20 ppm.
[0008] Particularly, down and feathers from chickens, ducks, geese, and eider are used for the manufacturing of natural stuffing. An appropriate silver material may be bought in a solution of 1,000 ppm from Shanghai Iluzhong Nano Technology Co. Ltd.
[0009] The silver particles are applied during the washing process, where initially the concerned down and feathers are subjected to a raw wash with mainly clean water, potentially added an antibacterial soap. Subsequently, the actual wash with alkaline soap is performed in a controlled manner in order to remove fatty substances. Subsequent to the wash, the feathers and down are rinsed three times with clean water, and the silver material is applied to the third change of rinsing water. After the rinse, the natural stuffing is dried in a tumble dryer. Finally, the natural stuffing is sorted according to quality.
[0010] 200 kg washed down and feathers rinsed in 120 I water are e.g. added 1,000 ppm silver material.
[0011] As mentioned, the silver material in question has a preferred size of ≦5 nm. The amount of silver in the end product is preferably 5 ppm.
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A natural duvet/pillow stuffing, which consists of down and feathers with silver particles. The size of said silver particles is ≦5 nm.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a coating technique, and more specifically, to a coating technique for a gas phase synthesized diamond film.
Diamond is the hardest material in the world, has a Vicker's hardness of 10,000 and a high Young's modulus and heat conductivity, and a superior wear resistance and chemical stability, and these superior properties of diamond lead to hopes for various applications thereof as a bulk material or as a coating material. For example, a diamond film could be applied as a wear resistant coating, as a speaker diaphragm, and as a transparent coating for an optical component.
2. Description of the Related Art
The synthesizing of diamond under high temperatures and high pressures, and recently, by a gas phase chemical reaction process (CVD), has long been studied.
For example, a technique for a chemical vapor deposition of a diamond film by a plasma CVD of CH 4 gas diluted with H 2 has been proposed. In this process, due to the plasma in the plasma CVD, the H 2 is excited and activated H atoms are produced, which remove the amorphous carbon and carbon deposits other than diamond, leaving only the diamond, and thus enable the growth of a diamond CVD film.
Nevertheless, a gas phase synthesized diamond film in general has a very low adhesion strength, and although attempts have been made to increase the nuclei forming density of diamond and provide carbides and other intermediate layers, to thus improve the adhesion strength, good results have not been obtained.
The present inventors further developed the DC plasma jet CVD process for a high speed gas phase synthesis of diamond (see Japanese Unexamined Patent Publication No. 64-33096), and proposed a process for forming a plasma sprayed film including diamond by supplying metal and ceramic powder into the plasma during the synthesis of diamond in the DC plasma jet CVD process (Japanese Unexamined Patent Publication No. 2-22471). In this process, an intermediate layer composed of a plasma spraying material and diamond is formed between the plasma sprayed film and the diamond film, and a high adhesion strength is thus obtained.
FIG. 8 shows an apparatus for the production of a coating film formed of a mixed layer of a plasma spraying material and diamond in accordance with the above process.
The anode 1 surrounds the cathode 2, to thereby form a gas passage 3 for the synthesizing gas, etc. Further, a DC power source 4 is connected between the anode 1 and the cathode 2 and a plasma forming gas, such as a mixed gas of H 2 gas and CH 4 gas, is supplied to the gas passage 3 for the synthesis of diamond. When a DC voltage is applied across the anode 1 and the cathode 2, to produce a DC discharge, a plasma is formed. In FIG. 8, a nozzle 5 for supplying the powder is formed at the tip of the anode 1, and a carrier gas 6 including the plasma spraying powder is supplied from the nozzle 5. The plasma spraying powder is melted in the plasma, is deposited on the surface of the substrate 7, and is solidified to plasma a flame sprayed film.
When Ar or another inert gas is supplied to the gas passage 3 and plasma spraying powder is supplied from the nozzle 5, it is possible to form a plasma sprayed film on the substrate. If powder is not supplied from the nozzle 5 but a diamond synthesis gas is supplied to the gas passage 3, then it is possible to form a diamond film on the substrate. Further, if a diamond synthesis gas is supplied to the gas passage 3 and plasma spraying powder is supplied to the nozzle 5, then the plasma spraying and synthesis of the diamond gas phase are conducted simultaneously, and thus it is possible to form a mixed film of a plasma spraying material and diamond on the substrate.
For example, first a plasma sprayed film 8 comprised of the same material as the substrate, or a material having a good affinity therewith, is formed on the substrate 7, a mixed film 9 of the plasma spraying material and diamond is formed thereover, and a diamond gas phase synthesized film 10 then formed as a top film thereover.
In such a laminated structure, even if, for example, the substrate 7 and diamond film 10 have vastly different thermal expansion coefficients, a diamond film 10 can be formed on the substrate 7 with a good adhesion strength.
Nevertheless, in the conventional process explained above with reference to FIG. 8, the following problems arise:
(1) It is difficult to separately control the conditions for the plasma spraying and diamond synthesis.
(2) During the formation of the mixed layer, the plasma spraying powder is melted in a plasma mainly composed of hydrogen, and thus is adversely affected by the hydrogen.
(3) Since a DC arc discharge is used, the electrode material becomes mixed in the film.
(4) Since a DC arc discharge is used, the discharge is not stable.
(5) The speed of the formation of the diamond film is relatively slow and it is difficult to supply fine amounts of the plasma spraying powder in accordance with same.
A solution to these problems is required.
SUMMARY OF THE INVENTION
Accordingly, the object of the present invention is to solve at least one of the above problems and to provide an easily controlled technique for the production of a high quality diamond film having a good adhesion strength.
Other objects and advantages of the present invention will be apparent from the following description.
In accordance with the present invention, there is provided a process for the production of a coating film comprising a step of forming a mixed layer of a plasma spraying material and diamond, characterized by including a step of conducting plasma flame spraying by a plasma spraying torch, and simultaneously conducting a plasma CVD by a CVD plasma torch, to thereby form a mixed layer on a substrate.
In accordance with the present invention, there is also provided a process for the production of a coating film comprising a step of forming a mixed layer of a plasma spraying material and diamond, characterized by a step of generating a plasma by a single plasma torch by using either an RF discharge or a laser breakdown discharge and conducting a plasma spraying and plasma CVD to thereby form a mixed layer.
In accordance with the present invention, there is further provided a process for the production of a coating film comprising a step of forming a mixed layer of a plasma spraying material and diamond, characterized by step of conducting a plasma spraying while supplying a plasma spraying material in the form of a wire, to thereby form the mixed layer.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood from the description set forth below with reference to the accompanying drawings, wherein:
FIG. 1 is a sectional schematic view of a film forming apparatus having two DC plasma torches according to an embodiment of the present invention;
FIG. 2 is a sectional schematic view of a film forming apparatus having an RF plasma torch according to another embodiment of the present invention;
FIG. 3 is a sectional schematic view of a film forming apparatus having a laser breakdown plasma torch according to still another embodiment of the present invention;
FIG. 4 is a sectional schematic view of a film forming apparatus having a laser breakdown plasma torch and a wire supply apparatus according to another embodiment of the present invention;
FIG. 5 is a sectional schematic view of a film forming apparatus having two laser breakdown plasma torches and a wire supply apparatus according to another embodiment of the present invention;
FIG. 6 is a sectional view of an example of the structure of a formed film;
FIG. 7 is a graph showing the results of a measurement of a sample of an example of the laminated structure prepared by using the film forming apparatus of FIG. 5;
FIG. 8 is a sectional schematic view of the structure of a film forming apparatus according to the prior art; and
FIG. 9 is a graph showing the results of a measurement of a sample of an example of a laminated structure prepared by using the film forming apparatus of FIG. 8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The difficulty of carrying out a separate control of the plasma spraying and diamond synthesis conditions, and the susceptibility of the plasma spraying material to the effects of hydrogen, are due to the use of the diamond synthesis torch for the plasma spraying, under diamond synthesis conditions. These problems are solved by separating the diamond synthesis torch and the plasma spraying torch and conducting the CVD and plasma spraying under appropriate respective conditions.
The problem of an intrusion of the electrode materials into the film arises due to the use of a DC discharge and a consumption of the electrode material. This problem can be solved by generating a high temperature plasma by an RF (Radio high frequency) discharge or laser breakdown discharge, which breaks down the gas with a condensing type large output laser to make a plasma, and other discharge methods not requiring the use of electrodes.
Further, these discharge processes are more stable than a DC discharge, and therefore, the problem of the instability of the discharge also can be solved.
Note that the desired effects can be obtained by the use of these processes for at least one of the plasma spraying and diamond synthesis.
The problem of the difficulty of supplying finely controlled amounts of the plasma spraying material, in accordance with the speed of diamond film formation, arises due to the lack of an apparatus for supplying fine amounts of powder; however by using a wire instead of powder, and making the wire diameter small and slowing the supply speed thereof, it is possible to supply fine amounts of plasma spraying material matching the speed of formation in the diamond gas phase synthesis.
First, the main aspects of the embodiments of the present invention will be shown in the following table:
______________________________________ Supply of plasma For diamond For plasma sprayingTorch synthesis spraying material______________________________________Single DC PowdertorchSingle 1) RF 1) Powdertorch 2) Laser breakdown 2) WireSeparate 1) DC 1) DC 1) Powdertorches 2) Laser breakdown 2) RF 2) Wire 3) Laser breakdown______________________________________
Note that a DC plasma torch has advantages such that it has a simple construction and a relatively low cost, the output thereof can be easily increased, the velocity of the plasma can be made faster, and the torch and substrate can be placed apart from each other.
An RF plasma torch has advantages such that it can prevent an intrusion of impurities and has an excellent discharge stability.
Further, a laser breakdown plasma torch has advantages such that it can prevent an intrusion of impurities, has an excellent discharge stability, and provides an excellent controllability of the film formation.
On the other hand, a DC plasma torch suffers from an intrusion of W and other electrode materials into the film, and does not have a satisfactory discharge stability.
An RF plasma torch has a slow plasma verosity and cannot be placed far apart from the substrate. Also, when the diamond CVD is conducted by an RF plasma torch, it is difficult to conduct the plasma spraying by using a separate torch.
Further, a laser breakdown plasma torch is of a higher cost and it is difficult to increase the output thereof.
These methods can be suitably selected and used in accordance with a specific object.
For example, when using separate torches, a DC plasma or laser breakdown plasma torch can be used for the diamond synthesis torch, any one of a DC plasma, RF plasma, or laser breakdown plasma torch can be used for the plasma spraying torch, and the plasma spraying material can be supplied as a powder or wire, and accordingly, twelve (12) process combinations are possible.
Therefore, as shown in the table, seventeen (17) combinations can be made.
FIG. 1 is a schematic view explaining the formation of a coating film using two torches, according to an embodiment of the present invention.
In a reduced pressure chamber (not shown) connected to an exhaust apparatus, there are arranged two torches T1 and T2. The first torch T1 is used for diamond synthesis and the second torch T2 is used for plasma spraying. These torches have anodes 14 and 15 and cathodes 12 and 13, respectively, and DC power sources 22 and 23 are connected therebetween. Also, gas passages 18 and 19 are formed between the respective anodes 14 and 15 and cathodes 12 and 13. Further, outside members 16 and 17 are arranged so as to surround the anodes 14 and 15, whereby gas passages 20 and 21 are formed. In the first torch T1, separate gas passages are thus defined between the anode 14 and the cathode 12 and between the anode 14 and the outer member 16, to supply, respectively and for example, H 2 gas and CH 4 gas. Further, in the second torch T2, for example, a plasma forming gas (for example, Ar) flows in the gas passage between the cathode 13 and the anode 15 and a plasma spraying material powder, carried in a carrier gas, flows in the gas passage between the anode 15 and the outside member 17.
In the first torch T1, it is possible to synthesize diamond by applying a DC voltage across the cathode 12 and the anode 14, supplying H 2 gas to the inside gas passage 18, and supplying CH 4 gas to the outside gas passage 20.
In the second torch T2, it is possible to conduct plasma spraying of the plasma spraying material by supplying Ar gas to the gas passage 19 as the plasma forming gas and supplying a plasma spraying material powder mixed in an Ar carrier gas to the outside gas passage 21. Note, in the figure, 24 and 25 show the formed plasma jets.
When the diamond synthesis torch T1 and the plasma spraying torch T2 are separately controlled, the plasma spraying film 8 is first formed on the substrate 7, then the plasma sprayed/diamond mixed layer 9 is formed, and the diamond film 10 is formed as the top film.
Because an exclusive torch T2 is used for the plasma spraying, the conditions suited for the plasma spraying can be selected separately from those of the diamond synthesis. Further, it is possible to freely select the plasma gas for the plasma spraying, and thus the effects of the hydrogen can be alleviated.
In an apparatus with two DC discharge torches as shown in FIG. 1, a Ti plasma sprayed film and Ti/diamond mixed film were formed on the Ti substrate as intermediate layers, and a diamond film was formed thereon. The substrate 7 was a 20×20×5 mm Ti plate, the temperature of the substrate during film formation was about 900° C., and the pressure was 50 Torr. The Ti plasma spraying conditions were an Ar flow rate of 10 liters/min., an output of 30 kW, an average particle size of the Ti powder of 5 μm, and a plasma spraying speed of 5 to 20 μm/min. The conditions for the diamond synthesis were a flow rate of the hydrogen gas of 50 liters/min., a flow rate of methane gas of 1 liter/min, and an output of 5 kW. The speed of diamond film formation under these conditions was about 1 μm/min. The steps in the film formation were first, establishing a sufficient separation of the substrate from the torches, producing ignition of the two torches, and establishing a stable state. At this time, the supply of the plasma spraying powder was controlled to obtain a plasma spraying speed of 20 μm/min. Next, the substrate was moved to a predetermined position and the film formation was started. After 5 minutes of film formation, the plasma spraying speed was gradually reduced over 5 minutes to 5 μm/min. A plasma spraying speed lower than this is difficult to control, and thus the supply of the plasma spraying powder was turned on and off as a control for reducing the average plasma spraying speed.
Finally, the supply of the plasma spraying powder was
stopped and the formation of only a diamond film was conducted for about 100 minutes.
FIG. 6 is a schematic view of the laminated structure formed above.
A plasma sprayed Ti layer 51 is formed on top of the Ti substrate 50, a Ti/diamond gradient composition mixed layer 52 is formed on top of that, and a diamond layer 53 is formed on top of that.
A sample having the structure shown in FIG. 6 was subjected to tests after the formation of the film. The sample section was examined by X-ray diffraction, and further was heated to 500° C. and then cooled with water to give a heat shock thereto. As a result of a micro X-ray diffraction of the section, a slight amount of TiC was detected in addition to the Ti from the plasma sprayed Ti layer 51, and Ti, TiC, and diamond were detected from the mixed layer 52. Further, only diamond was detected from the diamond layer 53. The process produced a vastly superior purity in all of the plasma sprayed layer, mixed layer, and gas phase synthesized layer. Further, the heat shock test was repeated three times, but no peeling or cracking of the film occurred, and accordingly, it was proved that the adhesion strength was excellent.
Note, to compare the formation of the coating film by the embodiment shown in FIG. 1 with the formation of a coating film by the prior art shown in FIG. 8, the production apparatus of FIG. 8 was used to form the same layered structure as in FIG. 6. The same tests as above were performed on a sample formed in this way, i.e., the section was examined by X-ray diffraction and a heat shock test was performed by heating the sample to 500° C. and then cooling it with water.
As a result of a micro X-ray diffraction of the section, only a slight amount of Ti was detected from the Ti layer 51, and almost all of the rest was TiC. Further, in the heat shock test, the diamond film cracked after a single test and a partial peeling also occurred. The peeled sample was investigated, and the peeling was found to have occurred between the Ti substrate 50 and the Ti plasma sprayed film 51.
The reasons for the peeling in the prior art structure are believed to be the change of Ti to TiC due to the supply of Ti powder in the hydrogen/methane plasma, and the differences in the heat expansion coefficients of the Ti substrate 50 and the plasma sprayed layer 51, and the embrittlement due to the absorption of hydrogen, which reduced the toughness of the plasma sprayed layer, etc. Note, the significance of the above-mentioned embodiment is made clear by this comparative test.
FIG. 2 is a schematic view explaining the formation of a plasma sprayed/diamond film using an RF discharge according to another embodiment of the present invention.
An RF coil 30 is wrapped around the outer circumference of an RF torch pipe 26. The RF torch pipe 26 is provided with a gas introduction port 32 for the supply of plasma gas and a gas introduction port 33 for the supply of a carrier gas carrying the plasma spraying powder. The RF coil 30 receives a supply of RF power from an RF oscillator 31, and thus a plasma 34 is formed in the RF torch pipe 26. A substrate 7 is placed on a substrate holder 37, and using the thus formed RF plasma torch T3, a plasma sprayed layer 8 is formed on top thereof, followed by a plasma sprayed/diamond mixed layer 9, a diamond layer 10, and other films.
For example, an Ar-based gas mixed with hydrogen and methane is used as the plasma gas, an Ar gas carrying the plasma spraying powder is supplied as the plasma spraying powder gas, and a plasma sprayed/diamond mixed layer is formed.
Using the production apparatus shown in FIG. 2, a plasma was formed by an RF discharge and an attempt was made to form a diamond film on an SiC substrate, with an SiC intermediate layer. The substrate was an SiC substrate of 10×10×3 mm, the plasma spraying particles were SiC having an average particle size of 1 μm, the plasma spraying speed was 10 to 2 μm/min, the Ar gas flow rate was 20 liters/min., the hydrogen rate was 5 liters/min., the methane rate was 0.3 liter/min., the RF output was 20 kW, and the substrate temperature was 950° C. SiC was plasma sprayed for 10 minutes at a flame spraying speed of 20 μm/min., then the speed of supply of powder was gradually reduced, and finally, only diamond was grown, whereupon a diamond film was formed to a thickness of approximately 200 μm.
The elements of the film were analyzed by a mass spectroscope (SIMS), whereupon a minute amount of B was detected in addition to the Si, C, and H from the plasma sprayed layer 8. A small amount of Si was detected from the diamond film 10 in addition to C and H.
The same tests were performed in accordance with the prior art using a DC discharge and provided with W electrodes, whereupon a large amount of the electrode material W was detected in both the plasma sprayed film and the diamond film.
Compared with the prior art, it was found that the above embodiment enables the formation of a plasma sprayed layer and diamond layer having a higher purity.
FIG. 3 is a schematic view explaining the production of a coating film by another embodiment, using a laser breakdown.
The laser beam 38 from a large output CO 2 laser (not shown) is condensed by a condenser 39; further on a funnel shaped wall 40 surrounding the condensed laser beam there is provided a plasma gas supply port 40a. Further, at the edge of the constricted wall 40 is formed a nozzle 42, from which heated and expanded plasma 43 is ejected. Near the nozzle 42 is arranged a powder gas supply port 41 from which is ejected a mixture of the plasma spraying powder and carrier gas, to thereby form the torch T4.
The substrate 7 is placed on the substrate holder 37, which in turn is arranged under the nozzle 42, and a plasma sprayed/diamond mixed layer, etc., is formed on top of the substrate 7.
To the plasma gas supply port 40a there is supplied, as the plasma gas, a mixed gas of hydrogen and methane, to conduct the plasma CVD, and to the powder gas supply port 41 there is supplied an Ar gas containing the plasma spraying powder as the powder gas for the plasma spraying, to thereby form the plasma sprayed film 8, the mixed layer 9, and the diamond layer 10, etc.
FIG. 4 shows the constitution, or assemblage of a combination of a laser breakdown torch T4 with a wire supply apparatus, as an apparatus for supplying the plasma spraying material.
The condenser 39, wall 40, plasma gas supply port 40a, nozzle 42, and substrate holder 37 are the same as those in FIG. 3. Underneath the nozzle 42, instead of the powder gas supply port, a wire supplying apparatus 44 is provided, i.e., the wire 46 of the plasma spraying material is wound on a wire roll 49, sent to a feed roller 48, and supplied from a wire guide 47 underneath the nozzle 42. If the diameter of the wire 46 of the plasma spraying material is made smaller and the feed speed is slowed, it is possible to reduce the speed of the supply of the plasma spraying material as desired. In this method, if the stability of the plasma gas is poor, the speed of plasma spraying finally will fluctuate, but by using a highly stable plasma gas, it is possible to conduct a stable plasma spraying. The laser breakdown process has a particularly superior plasma stability, and further, the arc can be made smaller whereby it is possible to form a plasma sprayed film with a good controllability.
An attempt was made to form a diamond film on an Mo substrate via an NbC intermediate layer, using the apparatus shown in FIG. 4.
As the laser, use was made of a gas flow type CO 2 laser and a laser beam 38 having an oscillation wavelength of 10.6 μm was obtained. Note, the output of the laser beam 38 was 2 kW. The Mo substrate was a plate 20×20×1 mm, the plasma spraying wire was an Nb wire 0.1 mm in diameter, the gas flow rate was 10 liters/min. of hydrogen and 0.2 liter/min. of methane, and the substrate temperature was 800° C. The flame spraying speed was determined by the feed rate of the Nb wire and was 1 cm/min. The film was formed by first, continuing the plasma spraying at a wire feed rate of 20 cm/min. for 30 minutes, gradually reducing the wire feed rate over 60 minutes to zero, and then stopping the plasma spraying with the wire. Further, the diamond film was formed over 50 minutes.
After the formation of the film, a section of the sample was subjected to point analysis and line analysis by SIMS to determine the presence of introduced impurities and the state of the inclined or graded composition. As a result of the point analysis, Nb, C, and H were detected from the flame sprayed film and C and H from the diamond film, and it was found that there was no intrusion of impurities other than H.
The results of the line analysis are shown in FIG. 7.
In the region of the Mo substrate, only Mo was detected, and in the region of the NbC plasma sprayed layer, certain percentages of Nb and C were detected. Preferably, in the NbC/diamond gradient composition mixed layer, the Nb is gradually reduced and the C is gradually increased, and in the diamond layer, the C is detected at a certain strength.
For comparison, the same constitution of a plasma sprayed/diamond film was formed by a DC discharge and powder plasma spraying technology. The results of line analysis of the sample by this comparative art are shown in FIG. 9. The desirable measurement characteristics are the same as those explained with respect to FIG. 7. A comparison of FIG. 7 and FIG. 9 shows that, in the case of the film forming method of the above-mentioned embodiment, an extremely high and thus far greater precision control of the composition is possible.
FIG. 5 is a schematic view of a double torch type film forming apparatus combining a laser breakdown CVD T'1 and laser breakdown wire flame spraying T'2.
The two laser generators 54 and 55 are respectively used for the plasma spraying and the CVD. The laser beams 56 and 57 emitted from the lasers 54 and 55 are condensed by the condensers 58 and 59 and shot from the nozzles 60 and 61 onto the plasma jets 66 and 67. The plasma spraying wire 46 is supplied from the wire supplying apparatus 44 underneath the plasma spraying nozzle 60. The nozzles 60 and 61 are arranged in the reduced pressure chamber 71 connected to the exhaust system 72 and a plasma sprayed film and CVD film are deposited on the substrate 7 placed on the substrate holder 37. Note, the gas supply apparatus 73 for supplying the desired gas is connected through the gas conduits 62 and 63 to the plasma spraying system T2' and CVD system T1'.
As the laser generator, use is made of a gas flow type CO 2 laser and, the laser beam, a laser beam of an oscillation wavelength of 10.6 μm and an output of 2 kW is obtained. The lenses and nozzles are arranged so as to be adjustable upward and downward by the bellows 64 and 65, so that the distances from the substrate of the two plasma jets can be controlled independently.
Using the apparatus shown in FIG. 5, a diamond film was formed on an Mo substrate via an Mo plasma sprayed intermediate layer, and a test was run by plasma spraying copper thereon. The substrate was a 20×20×2 mm Mo plate, and the plasma spraying wires were Mo wire 0.1 mm in diameter and copper wire 0.1 mm in diameter. The conditions of the plasma spraying torch were a gas flow rate of 5 liters/min. Ar and a laser output of 2 kW in the case of the Mo, and 1 kW in the case of Cu. The conditions of the diamond synthesis torch were a gas flow rate of 10 liters/min. hydrogen and 0.4 liter/min. methane, a laser output of 2 kW, and a film forming speed of 3 μm/min. Further, the pressure was 100 Torr and the substrate temperature 800° C.
An Mo/diamond gradient composition layer was first formed on the substrate to a thickness of approximately 30 μm, then a diamond film was formed to approximately 200 μm. On top thereof was formed a diamond/Cu gradient composition layer to a thickness of approximately 20 μm, and finally, Cu was plasma sprayed to a thickness of approximately 50 μm. A section of the sample prepared in this way was examined by micro X-ray diffraction and SIMS. Further, the surface of the sample was polished and a copper tensile test fitting was brazed thereto to measure the adhesion strength. As a result of the analysis of the section by micro X-ray diffraction, only a slight amount of MoC was detected from the Mo/diamond gradient composition layer, in addition to the Mo and diamond, and diamond and Cu were detected from the diamond/Cu gradient composition layer.
In the SIMS analysis, only Mo, C, Cu, and H were detected, and further, in the tensile test, the brazed portion peeled at about 1000 kg/cm 2 .
In the case of the film structure of the same type prepared by a single DC discharge torch as in the past, it was observed from X-ray diffraction that the majority of the plasma sprayed Mo layer was MoC. Further, from SIMS analysis, the electrode material W was detected in addition to Mo, C, H, and Cu. Also, in the tensile test, the Cu and diamond peeled from each other at 300 kg/cm 2 .
Accordingly, by using two laser breakdown torches T1' and T2' to conduct the diamond CVD and flame spraying, it is possible to form an extremely tough diamond film.
The diamond coating explained above may be used as a coating on, for example, tools or sliding members, or as an insulation coating for heat sinks.
The present invention was explained above in accordance with specific embodiments, but the present invention is not limited thereto. For example, as will be clear to persons skilled in the art, various changes, improvements and combinations are possible.
As explained above, according to the present invention, it is possible to prepare a plasma sprayed film and diamond film under respective suitable conditions by separating the diamond synthesis torch and the plasma spraying torch respectively employed for forming the plasma spraying film and the diamond film.
Further, by using a separate plasma spraying torch, it is possible to use an inert gas for plasma spraying, and thus to prevent hydrogen, carbon, etc. from affecting the plasma spraying particles. Therefore, it is possible to prevent spoiling of the plasma spraying material and resultant reduction of the strength.
Also, by using an RF discharge and a laser breakdown respectively to form the plasma and to form the plasma sprayed film and diamond film, it is possible to prevent an intrusion of the electrode material due to electrode wear, and thus reduce the impurities. This enables an improvement in the purity of the plasma sprayed film and diamond film.
Further, by supplying the plasma spraying material into the plasma in the form of a wire, it is possible to raise the controllability at low plasma spraying speeds and to smoothly change the gradient composition of the plasma sprayed/diamond gradient composition mixed layer. This enables an improvement of the reproducibility and reliability of the plasma sprayed/diamond gradient composition mixed layer.
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A process for forming a diamond gas phase synthesized coating film which is easily controlled and affords a high quality, good adhesion strength diamond film includes a step of forming a mixed layer of a plasma spraying material and diamond by simultaneously conducting plasma injection by a plasma spraying, a first torch and plasma CVD by a CVD plasma, second torch to thereby form a mixed layer on the substrate. The first and second torches are structurally distinct and have respective, separately and selectively controlled plasma generation operating conditions.
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This application is a continuation of application Ser. No. 08/532,273 filed Sep. 22, 1995, now abandoned.
This invention relates to treatment of bioorganic and/or waste water sludge in coordination with the accelerated composting of green wastes.
DEFINITIONS
1. Process to Significantly Reduce Pathogens (PSRP) (Established CFR 257, Sep. 13, 1979)
PSRP is the minimum disinfection and stabilization requirement of U.S. Environmental Protection Agency. Processes so classified, i.e., aerobic digestion, anaerobic digestion, lime stabilization (pH>12 for two hours), produce sludges which may be land filled or land applied on non-food chain crops with stringent public access restrictions and grazing restrictions. Such processes must demonstrate ability to reduce pathogen concentrations by 90%. As set forth in the specification of the U.S. Pat. No. 4,902,431, in a Nov. 6, 1985 memorandum, the EPA indicated that to qualify a process as a PSRP one must demonstrate that the process reduces animal viruses by one log and pathogenic bacterial densities by at least two logs and must reduce the vector attractiveness such that vectors, like flies or rats, are not attracted to the sludge.
More recently, the USEPA has adopted a Class B regulation to replace the PSRP. Although the impact of the Class B regulations is to achieve a similar microbial content as specified in the above paragraph there are three alternatives requirements for demonstrating the achievement of this pathogen reduction, but basically, the fecal coliform density in the treated sludge must be 2 million colony forming units per gram total solids sewage sludge on a dry weight basis. The alternatives for reaching this standard are defined by reference to the USEPA publication EPA/625/R-92/013 which was published in December of 1992 and formed the basis of the Class B pathogen reduction rules of the 40CFR part 503 rules which were promulgated by the USEPA in early 1993.
2. Process to Further Reduce Pathogens (PFRP) (Established 40 CFR 257, Sep. 13, 1979)
PFRP is the most stringent criteria established by U.S. EPA for disinfection and stabilization of sewage sludges. Processes so classified must demonstrate the ability to reduce pathogen concentrations below detectable levels. Processes directly identified in 40 CFR 257 were compost, heat drying (>80 C.+ moisture content below 10%), and heat treatment (>180 C. for 30 minutes). Also with "add-on" processes to PSRP processing such as high heat pasteurization, the sludge must be maintained for at least 30 minutes at a minimum temperature of 70 C. in order to be deemed as Processes to Further Reduce Pathogens in 40 CFR 257.
At the time of publication of 40 CFR 257, no criteria were established for PFRP processes.
As indicated in U.S. Pat. No. 4,902,431, on Nov. 6, 1985, the EPA issued a memorandum indication that to qualify a process as PFRP one must demonstrate reduction of pathogenic bacteria, animal viruses, and parasites "below detectable limits" of one (1) plaque forming unit (PFU) per 100 ml of sludge for animal viruses; three (3) colony forming units (CFU) per 200 ml of sludge for pathogenic bacterial (Salmonella sp.); and one (1) viable egg per 100 ml of sludge for parasites (Ascaris sp.). Vector attractiveness must also be reduced for PFRP.
NOTE: PFRP regulations do not require the survival of any non-pathogenic organisms. In fact, many PFRP processes result in sterilization, i.e., the destruction of all microorganisms.
More recently, the USEPA has adopted a Class A regulation to replace the PFRP. Although the impact of the Class A regulations is to achieve the same microbial content as specified in the above paragraph there are a variety of alternatives requirements for demonstrating the achievement of this pathogen reduction. These are defined by reference to the USEPA publication EPA/625/R-92/013 which was published in December of 1992 and formed the basis of the Class A pathogen reduction rules of the 40CFR part 503 rules which were promulgated by the USEPA in early 1993.
3. Land Application
Land application is the traditional method of sludge utilization. PSRP sludges are a minimum requirement, but may only be used on secure fields with substantial restrictions. Public access is prohibited with PSRP sludges. PFRP has no restrictions.
4. Disinfection
Disinfection is the destruction of pathogens, i.e., disease causing microorganisms, to some quantitative level.
5. Stabilization
Used in two ways:
a. The ability of a process to maintain levels of disinfection by preventing pathogen regrowth.
b. The ability of a process to reduce odors and to prevent odor redevelopment.
6. Sterilization
Sterilization is the complete destruction of all microorganisms in a substance.
7. Pasteurization--Conventional definition
Pasteurization is the destruction of all pathogenic microorganisms except bacterial spores.
8. Adsorptive Material
Adsorptive material is a material capable of binding organic and inorganic substances to its surface.
9. USEPA
United States Environmental Protection Agency, ("USEPA").
10. Yard waste
Mechanically ground vegetation, wood chips , leaves and grass clippings
11. Green Waste
Any vegetative waste including yard waste or agricultural crop remains and either green or woody vegetation remains
12. Bioorganic sludge
An organic sludge comprised of a material or materials selected from the group: sludges resulting from production of antimicrobials and other pharmaceutical products, bacterial fermentation sludges, sludges resulting from production of beer and wine, mushroom compost waste, paper mill sludges, sludges that contain microorganisms that have resulted from recycled organic products such as paper products, sludges resulting from the growth of microorganisms for the production of chemicals and organics, industrial sludges and byproducts resulting from the production of microbial products and foodstuffs, sludges resulting from the animal slaughter industry--particularly if these are digested or otherwise broken down by microorganisms; sludges comprised of animal manures, as in chicken or horse manure.
13. Organic sludge
A sludge derived from industrial products and byproducts that are comprised in the majority microbially degradable organic materials not of biological or microbiological origin. This definition would include sludges comprised of recycled organic products such as recycled paper and paper products.
14. Class A wastewater sludge treatment
Sludges treated similarly as to achieve the microbial status in the PFRP definition above but as technically defined in the US 257 Part 503 rules published in February, 1993 by the USEPA.
15. Compost
A group of organic residues or a mixture of organic residues and bulking agents that have been piled, moistened, and allowed to undergo aerobic biological decomposition.
16. Composting
The process of creating a compost. To achieve the Class A or PFRP designation using the within-vessel composting method, the solid waste is maintained at operating conditions of 55 C. or greater for 3 days. Using the static aerated pile composting method, the solid waste is maintained at operating conditions of 55 C. or greater for 5 days. Using windrow composting method, the solid waste attains a temperature of 55 C. or greater for at least 15 days during the composting period. Municipal greenwaste composting operations often take three to six months or more to achieve stability.
17. Composting amendment
An ingredient in a mixture of composting raw materials included to improve the overall characteristics of the mix. Amendments often add carbon, dryness, or porosity to the mix.
18. Alkaline byproducts
Highly adsorbent alkaline materials selected from the group consisting of cement kiln dust, lime kiln dust, fluidized bed ash, lime injected multistage burner ash, fine calcium oxide, dry sulfur scrubbing residue, slag fines, pulverized calcium carbonate, Class C or Class F fly ash, alkaline gypsum, alum, calcium carbonate sludge from water purification plants or a combination thereof.
BACKGROUND OF THE INVENTION
With the alternatives for bioorganic and/or wastewater sludge processing changing because of the public awareness of the problems of sludge dumping, either in landfills or oceans, the treatment of bioorganic and/or wastewater municipal! sludges by a sterilization or a pasteurization process is becoming increasingly common so that it is safe for exposure to the public as a product. In addition, it is becoming the practice of states and municipalities to prevent green wastes and yard wastes, especially leaves from being deposited in municipal landfills.
Under 40 CFR 257, a Process to Further Reduce Pathogens (PFRP) must be used where sewage sludge or septic tank pumping are to be applied to a land surface or are incorporated into the soil, and crops for direct human consumption are to be grown on such land within eighteen (18) months subsequent to application or incorporation. The 40 CFR 257 classifies the following PFRP processes:
Composting: Using the within-vessel composting method, the solid waste is maintained at operating conditions of 55 C. or greater for three days. Using the static aerated pile composting method, the solid waste is maintained at operating conditions of 55 C. or greater for five days. Using the windrow composting method, the solid waste attains a temperature of 55 C. or greater for at least fifteen days during the composting period. Also, during the high temperature period, there will be a minimum of five turnings of the windrow.
Heating drying: Dewatered sludge cake is dried by direct or indirect contact with hot gases, and moisture content is reduced to 10 percent or lower. Sludge particles reach temperatures will in excess of 80 C. or wet bulb temperature of the gas stream in contact with the sludge at the point where it leaves the dryer is in excess of 80 C.
Heat treatment: Liquid sludge is heated to temperatures of 180 C. for 30 minutes.
Thermophilic Aerobic Digestion: Liquid sludge is agitated with air or oxygen to maintain aerobic conditions at residence times of 10 days at 55-60 C., with a volatile solids reduction of at least 38 percent.
Other methods: Other methods of operating conditions may be acceptable if pathogens and vector attraction of the waste (volatile solids) are reduced to an extent equivalent to the reduction achieved by any of the above methods.
Any of the processes listed below, if added to the processes described in Section A above, further reduce pathogens. Because the processes listed below, on their own, do not reduce the attraction of disease vectors, they are only add-on in nature.
Beta ray irradiation: Sludge is irradiated with beta rays from an accelerator at dosages of at least 1.0 megarad at room temperature (ca. 20 C.).
Gamma ray irradiation: Sludge is irradiated with gamma rays from certain isotopes, such as 60 Cobalt and 137 Cesium, at dosages of at least 1.0 megarad at room temperature (ca. 20 C.).
Pasteurization: Sludge is maintained for at least 30 minutes at a minimum temperature of 70 C.
Other methods: Other methods of operating conditions may be acceptable if pathogens are reduced to an extent equivalent to the reduction achieved by any of the above add-on methods.
In U.S. Pat. Nos. 4,781,842 and 4,902,431 there is disclosed processes wherein:
wastewater sludge containing odor, animal viruses, pathogenic bacteria, and parasites is treated to provide a fertilizer for agricultural lands which can be applied directly to the lands which consists essentially of the following steps:
mixing said sludge with at least one alkaline material,
wherein the amount of added material mixed with said sludge being sufficient to raise the pH of said mixture to 12 and above for at least one day;
and drying said mixture to produce a granular material,
the amount of added material mixed with said sludge and the length of time of drying being sufficient to reduce significantly offensive odor of the sludge to a level that is tolerable; to reduce animal viruses therein to less than one plaque forming unit per 100 ml of said sludge; to reduce pathogenic bacterial therein no less than three colony forming units per 1 00 ml of said sludge; to reduce parasites therein to less than one viable egg per 100 ml of said sludge; to reduce vector attraction to said sludge; and to prevent significant regrowth of the pathogenic microorganisms.
In these processes, the alkaline material may comprise lime, cement kiln dust or lime kiln dust or other alkaline materials.
Other processes for treating wastewater sludge have utilized the concept of raising the pH in combination with high heat, e.g., greater than 70 C., to nearly sterilize, as contrasted to pasteurizing the sludge, thereby killing both undesirable and desirable bacteria. With these "add-on" processes usually the principal surviving microorganisms are bacterial spores. Such microbially-restricted sludges lose the significant fertility value associated with bioactivity.
When alkaline materials are added to a sludge to raise the pH, a toxicity may exist due to the high pH. When the product is used as a soil supplement in agriculture, particularly at high application rates, there is a risk of over alkalization of the soil (see FIG. 14) and burning of crops may result. In addition, a high pH (over pH 11) in the soil due to the addition of active alkaline materials containing calcium oxide or metal hydroxides can result in severe damage to microbial populations in surface soils. With most existing (traditional) alkaline technologies it has been required by the USEPA that the pH be maintained above pH 12 to prevent microbial overgrowth and instability. In fact, with the PFRP "add-on" heat processes, the pH is required by the USEPA to be maintained above 12 until the alkaline treated sludge is land applied. This requirement is based upon the recognition that when such sludges fall below pH 11 noxious odors will develop. U.S. Pat. No. 4,902,431 column 2 line 58-67 states: "In January 1979, the EPA published a Wastewater Sludge Manual (EPA 625/1-79-001) titled `Process Design Manual for Sludge Treatment and Disposal` which states: `Lime stabilization is a very simple process. Its principal advantages over other stabilization processes are low cost and simplicity of operation . . . lime addition does not make sludges chemically stable; if pH drops below 11.0, biological decomposition will resume producing noxious odors.`"
In addition, the high pH triggers the release of volatile ammonia nitrogen from the sludge which also is toxic and results in the loss of valuable nitrogen from the potential agricultural product. Further, the toxic nature of ammonia, i.e., to human and animal mucus membranes has been described as well as its lethal activity on microorganisms (see Meehan et al 1988 U.S. Pat. No. 4,793,927). Although having ammonia present during sludge stabilization processing is highly desirable for microbial control and for conditioning of the greenwaste to enhance its rapid breakdown, it is not desirable following treatment when the sludge product usage and exposure to the public is likely.
If these toxic stresses and the residual odor in a sludge product could be reduced upon demand, then opportunities for utilization of alkaline sludge products by the public and private sector would increase. This result would be favorable to increased emphasis on resource recovery of the value inherent in municipal sludge material. The present invention is able to accomplish such toxic stress reduction.
The process of U.S. Pat. Nos. 4,781,842; 4,902,431 requires a drying period which is usually effected by a windrowing process and results in a product that is above pH 12 and, if produced from an anaerobically digested sludge, emits significant amounts of ammonia. However the processes substantially reduce the emission of ammonia by aeration (such as windrowing) but to do so the processes are taking 3 to 10 days to prepare the product for storage or market. As evidence of health concerns over ammonia, states such as Ohio, New Jersey and California have implemented air quality standards regulating the emission of ammonia from industrial sites.
In U.S. Pat. Nos. 4,781,842, 4,902,431 and 5,275,733 Nicholson and Burnham teach the significant advantages of adding accelerated drying by aeration to alkaline treated sludges to achieve odor reduction and control. When windrows are used, this Nicholson and Burnham process commonly takes between 3 and 10 days to effect the aeration/drying. When mechanical dryers are used, as in the Burnham U.S. Pat. No. 5,275,733, the process is shortened to about 12 hours.
The Burnham U.S. Pat. No. 5,275,733 teaches that treated sludges may have an indigenous microflora established either naturally or by direct seeding as an ecologically active population in the sludge product. This microflora is critically significant to long-term sludge product stability because of its ability: a) to enhance by its own metabolism the carbonation of any residual hydroxides from the alkaline admixture or likewise the catabolism of unstable organics from the sludge; b) to reduce sludge odors and produce a soil-like odor; and c) to inhibit the regrowth of pathogenic microorganisms.
Another type of sludge that presently is causing a variety of problems to society with regard to proper disposal or use is a broad group of bioorganic sludges. These substances include organic sludges comprised of a material or materials selected from the group: sludges resulting from production of antimicrobials and other pharmaceutical products, bacterial fermentation sludges, sludges resulting from production of beer and wine, mushroom compost waste, paper mill sludges, sludges that contain microorganisms that have resulted from recycled organic products such as paper products; sludges resulting from the growth of microorganisms for the production of chemicals and organics, industrial sludges and byproducts resulting from the production of microbial products and foodstuffs, sludges resulting from the animal slaughter industry--particularly if these are digested or otherwise broken down by microorganisms, and sludges that are comprised of animal manures such as chicken or horse manure. The sludge material to be stabilized with greenwaste as per the treatment described in the present invention would also include sludges derived from industrial products and byproducts that are comprised in the majority microbially degradable organic materials not of biological or microbiological origin. This would include sludges comprised of recycled organic products such as recycled paper and paper products such as paper mill sludges. The most common disposal procedure is to landfill them thereby wasting their organic value and essentially delaying proper treatment. The second most common disposal procedure is to land apply them without further stabilization. This is significant for two reasons: one, these bioorganic sludges will usually provide an excellent substrate for anaerobic bacterial metabolism resulting in the creation of noxious odors and community problems, and two, these sludges without stabilization will create runoff problems with non-point source discharge pollution. The stabilization of sludges and greenwastes described in this invention will delay entry of the nitrogen into the ground water both avoiding contamination and allowing longer access for crops to the nitrogen in the stabilized product resulting from this invention.
This invention introduces a method to process these wastes along with bioorganic and/or wastewater sludges to produce a beneficial product for use as a soil substitute. The present invention introduces a method providing long term stability to bioorganic and/or wastewater sludges and concomitantly causes an accelerated composting of leaves and other green wastes so that a unique organic soil-like product is created unlike the alkaline stabilized sludges described in earlier patents, U.S. Pat. Nos. 4,781,842 and 4,902,431 and 5,275,733 and recent U.S. patent application Ser. No. 08/170705 filed, entitled "Process to Stabilize Bioorganic Raw or Treated Wastewater Sludge", or a green waste compost. Among the objectives of the present invention are to provide a method of treating and stabilizing bioorganic and/or wastewater sludges in coordination with the composting of leaves and other greenwaste to provide a beneficiated soil or fertilizer that has an improved odor.
SUMMARY OF THE INVENTION
In accordance with the invention, the method comprises the steps of treating and stabilizing a dewatered unprocessed sludge, i.e., raw sludge, or bioorganic sludges with an adsorbent alkaline material to effect odor reduction and accelerate the achievement of granularity and raise the pH of the sludge mixture to above pH 12, heating the sludge to at least 52 C. for 12 hours, seeding the sludge mixture, if necessary, so that a soil-like microflora develops, and blending into the process at different process locations, a greenwaste or greenwastes, preferably ground into small pieces, so that a biological action occurs converting the greenwaste into a soil-like product with improved odor over that of the treated municipal sludge alone or a composted greenwaste alone. This treatment lowers the pH of the mixture and enables subsequent microbial catabolism of unstable organics and further reduces and controls the long term odor of the treated sludge mixture so that the product odor develops a soil-like intensity and prevents the regrowth of pathogenic microorganisms and maintains stability in the sludge mixture. This beneficiating treatment results in a process that accomplishes the degradation and stabilization of the greenwastes faster than previously available by other technologies. This beneficiating treatment of adding the greenwaste will also have the desirable effect of significantly reducing the emission of ammonia nitrogen from the treated sludge product. The resultant bioactive product is useful as a soil substitute or as a fertilizer. A key objective of this invention is to enhance soil-like physical characteristics of the treated product, so that drying and odor control are achieved under conditions that allow the survival of an indigenous or seeded microflora.
The product of this invention has a number of physical, chemical and microbiological properties that make it a unique organic stabilized product. It has better odor characteristics than either alkaline stabilized pasteurized sludge product or leaf compost; microbial stabilization of the leaf organics by the alkaline stabilized pasteurized sludge product microflora and odor adsorption by the alkaline admixture reduce the putrefactive odor often found in leaf compost. High content of stable organics from the leaf compost aids in sorption or masking of the characteristic alkaline stabilized pasteurized sludge product odor. This combination of characteristics makes the product of this invention a superior material to either alkaline stabilized pasteurized sludge product or leaf compost as a synthetic organic soil substitute or fertilizer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic showing the addition of the greenwaste to the sludge processing stream at the time of the initial mixing of the alkaline adsorbant material with the sludge. Also illustrated is the embodiment of grinding or shredding the greenwaste as a means of accelerating the plant tissue degradation.
FIG. 2 is a schematic showing the addition of the greenwaste to the sludge processing stream immediately following the completion of the heat pulse step.
FIG. 3 is a schematic showing the addition of the greenwaste to the sludge processing stream immediately following the completion of the windrowing step for aeration and drying.
FIG. 4 is a schematic illustrating the production of alkaline stabilized pasteurized sludge product as taught by the prior art in U.S. Pat. Nos. 4,781,842 and 4,902,431.
FIG. 5. This figure shows the changes in total aerobic bacterial population numbers over time in coordination with the changes that were measured in the blended product of this invention with regard to pH, conductivity and percent solids.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In accordance with the present invention, a method of treating bioorganic or organic and/or wastewater sludge to provide a stable product for use as a beneficial soil or fertilizer for agricultural lands comprising the steps of; treating the bioorganic or organic and/or wastewater sludge with a highly adsorbent material so that odorant sludge organics and inorganics are bound to the adsorbent particles, adjusting the pH so that it is initially above pH 12 for the purpose of creating stress on the microbial pathogens present, adjusting the solids to a minimum of 50%, heating the sludge preferably with an exothermic reaction of the chemical energy contained in the alkaline admixtures in a step hereafter referred to as the "heat pulse step", and treating the sludge with greenwastes.
In accordance with the invention, the greenwastes may be added to the process, (1) along with the alkaline adsorbent material mixed with the sludge in the initial mixing process (FIG. 1); (2) directly to the heat pulse step after the initial mixing of the sludge and alkaline admixture has occurred, such that the greenwaste is subjected to the pasteurization process and ammonia gases, (3) immediately after the heat pulse step such that any residual heat and ammonia is used to partially pasteurize the leaves and begin the plant tissue conditioning process that accelerates microbial decomposition of the plant tissue and sludge organics (FIG. 2) and (3) after completion of or during the windrowing process for the stabilization of the alkaline sludge as per U.S. Pat. Nos. 4,781,842 and 4,902,431 (FIG. 3). The prior art for alkaline stabilization and pasteurization for sludges is illustrated in FIG. 4 as described in U.S. Pat. Nos. 4,781,842 and 4,902,431. The method causes the blending of an alkaline stabilized pasteurized organic, bioorganic or wastewater sludge to green waste in a ratio of between 1:10 and 1:0.5, and optimally at the ratio of 1:4 by volume.
If necessary, because of the absence of a sufficient microflora, the sludge/greenwaste mixture may be treated with a soil or an aged sludge product of this invention or a microbial culture so that the normal microflora of the soil, the sludge product or the culture is seeded directly into the sludge mixture, and the sludge mixture is permitted for a time sufficient to allow the microbial population under influence of the conductivity range to establish and to commence catabolizing the organics present in the sludge, to continue the odor reduction initially begun by the addition of the adsorptive material, to prevent pathogen regrowth, and to continue to carbonate any residual calcium hydroxide or oxide components. The method further optionally includes the steps of treating the sludge mixture with activated carbon to further reduce the odor. The sludge treated may be raw sludge, bioorganic sludge or PSRP or PFRP treated municipal sludge and is preferrably between 15% and 70% solids.
The significance of this invention is that the resultant sludge/greenwaste/mineral product is produced more rapidly than any other method available to date and that it has soil-like properties in that it is granular, has a soil-like odor, has an enhanced useful nitrogen fertilizer value and a microbial population that will facilitate odor control, long term stability, prevention of pathogen regrowth and add fertility value.
The present invention requires that an adsorbent material be mixed into the sludge to bind odorant organics and inorganics from the sludge and/or greenwastes. If this has been previously added as part of an earlier sludge treatment process then no additional adsorbent material need be added. If such an adsorbent material has not been added or has been added in a manner sufficient that the sludge mixture contains such adsorbent material comprising less than 30% of the wet weight of the sludge then additional adsorbent material must be mixed with the sludge until it equals or exceeds 30% of the wet weight of the sludge. This involves the method of adding adsorbents selected from a list comprised of cement kiln dust, lime kiln dust, fluidized bed ash, lime injected multistage burner ash, dry sulfur scrubbing residue, slag fines, pulverized calcium carbonate, Class C or Class F fly ash, alkaline gypsum, calcium carbonate water purification sludge, alum or a combination thereof, such that the percent solids of the mixture are increased to at least 50% and the pH of the mixture is temporarily raised to pH 12 or higher. It is important to understand that upon the addition of the greenwaste the pH will rapidly fall to between pH 7 and 9.5 due to the buffering capacity of the greenwaste and the microbial metabolism of the organics in the sludge and the greenwaste. In the preferred embodiment of this invention, the greenwaste is shredded and added to the 12 hour heat pasteurization step as described in U.S. Pat. No. 4,902,431. After the pasteurization incubation, the mixture is placed in windrows and aerated. The windrows should be mechanically mixed twice per week until the plant tissue is no longer visible in the product mixture.
If the treated sludge mixture at this point has not granulated following addition of the alkaline admixture as above, it may be processed through a dryer mechanism to remove water, especially if the greenwaste is to be added after the windrowing or mechanical drying is complete. If the sludge was originally not of a PPRP quality it could be heated to sterilization or near sterilization conditions, i.e., above 80 C., eg., as in 85 C., for several minutes by simply increasing the heat input to the dryer medium above to achieve PFRP prior to being further processed for microbial content as per the specifications of Alternative #1 for achieving Class A pathogen levels of the 1993 USEPA 40 CFR part 503 rule and the process of U.S. Pat. No. 5,275,733.
An indigenous microflora surviving a pasteurization process is enhanced by the addition of the greenwastes and will grow to a level which will effect the beneficiating activities of enhancing the carbonation of any residual hydroxides, the catabolism of unstable organics and the ability of this increased microflora population to prevent the regrowth of pathogenic microorganisms. Alternatively, a sterilized sludge mixture that is still deficient in beneficial microorganisms following the addition of the greenwaste must be seeded directly with a soil, the aged soil-like product of this invention, and/or a controlled microbial culture so that the sludge product of this invention will contain an indigenous microflora. This microflora should be within in the range of about 10 6 to 10 10 aerobic bacteria and about 10 4 to 10 7 fungi per gram soil solids and the bacteria added to the sludge mixture are to selected from a list representing the indigenous bacterial and fungal microflora of agricultural soils and wherein the bacteria added may include members of the actinomycete class of bacteria. The mixture will degrade due to the catabolic activity of the microorganisms such that an increase in osmolarity will occur in the mixture. This blending of a greenwaste with alkaline stabilized pasteurized organic or wastewater sludge causes microbial activity which results in a composting maturity defined by the increase of osmolarity in mmhos to a steady state of between 8 and 14 accompanied by a reduction in the C:N ratio to between 10 and 20. Following the aeration and drying steps, the sludge mixture can be matured by incubation under indigenous conditions which allow the odors which emanate from normal greenwaste composting to be controlled by the slow rate of microbial metabolism permitted under the conditions set up by the sequence of steps described for the method.
The final resultant stabilized sludge/greenwaste product should contain greater than 50% solids that has soil-like properties in that it is granular, has a soil-like odor, has an enhanced useful nitrogen fertilizer value over high alkaline treated sludges and a microbial population that will facilitate odor control, long term stability, prevention of pathogen regrowth and increased fertility value.
The product of this invention is neither that of a leaf compost nor an alkaline stabilized pasteurized sludge product alone, but possesses the best properties of both as a synthetic organic soil substitute. Table 1 lists the primary chemical and physical characteristics of the product of this invention. The pH and soluble salts in the product of this invention are lower than that of alkaline stabilized pasteurized sludge products and total N and organic matter contents are higher; The product of this invention is higher in total P and K than leaf compost, is a more uniform product than leaf compost and has higher available water holding capacity than an alkaline stabilized pasteurized sludge product.
This material has a slightly higher bulk density than that produced by the alkaline stabilized sludge products of U.S. Pat. Nos. 4,781,842, and 4,902,431. The total porosity is at the lower end of the range exhibited by these other materials, i.e., 64% by volume. The saturated hydraulic conductivity indicates that the product of this invention has good internal drainage for plant growth. Aggregate stability measurements showed this material to be different from the alkaline admixture sludge blends of these two patents in that there were fewer large aggregates formed with the product of this invention. The product of this invention showed more smaller aggregates particularly in the 0.5-0.25 mm weight fraction again resembling the characteristics of a Hazleton sandy loam (Logan and Harrison, 1994).
TABLE 1______________________________________Characteristics of the Product of this Invention.Character Mean*______________________________________Volatile Solids (%) 13.6Total Carbon (%) 8.52TKN (%) 0.45C:N 18.9:1Ammonia-N (ug/g) 383Nitrate-N (sat. extract (ug/ml) 67Calcium Carbonate Equivalent (%) 29pH 8.63EC (mmho/cm) (1:5 solid/solution) 8.32EC (mmho/cm) sat extract 29.8P (%) 0.42K (%) 0.29Ca (%) 9.97Mg (%) 4.08Fe (%) 1.58Trace Elements (ug/g)As 15.3B 138Cd 1Cu 71Cr 64Pb 33Hg <1Mn 180Mo 6.6Ni 80Sel 0.81Na 732Zn 260______________________________________Physical Properties Measure-Property Unit ment______________________________________Solids (%) 79Bulk density (g/cm.sup.3) 0.96Particle density (g/cm.sup.3) 2.66Porosity (% by volume) 64Moisture Retention Capacity 1/3 Bar Vol. fraction 0.3515 Bar (% moisture) 19Aggregate stability>5 mm (weight fraction) 0.115-2 mm 0.162-1 mm 0.111-0.5 mm 0.090.5-0.25 mm 0.30<.25 mm 0.23Saturated Hydraulic. Conductivity. (cm/s) 0.015Atterberg LimitsLiquid limit (% moisture) 54Plastic limit (% moisture) 27Plasticity index (% moisture) 28Particle size analysis>32 mm (% by weight) 0.0032-25.4 mm 0.0025.4-19 mm 0.0019-16 mm 0.0016-6.35 mm 6.116.35-4.7 mm 5.744.7-2 mm 26.71<2 mm 61.392-1 m (% of <2 mm fraction) 25.061-0.5 mm 36.430.5-0.25 mm 34.760.25-0.1 mm 2.760.1-0.074 mm 0.090.074-0.05 mm 0.02<0.05 mm 0.88______________________________________ *values reported are the mean of duplicate analyses.
EXAMPLE I
A stabilized, pasteurized wastewater sludge product made from a dewatered anaerobically digested sludge cake with fluidized bed ash and quicklime was mixed with either two volumes and four volumes of leaves collected by a municipal collection program. The leaves were mixed together with the sludge product using a scarab windrow mixing machine which created a windrow approximately 4 feet high and about 8 feet wide at the base. Initially the leaves and sludge product were mixed together twice. In samples of the mixed material leaves could be seen interspersed throughout the sludge product with their stems often intact and attached to the leaves. Windrow mixing of the leaf/sludge product mixture was carried out weekly and samples were taken for analysis. After about three weeks the leaf tissue was difficult to discern and the mixture had a very pleasant earthy odor very unlike the odor of the fresh pasteurized stabilized sludge product used to accelerate the leaf degradation. Conductivity analysis showed a steady state was achieved coincident with the disappearance of the leaf tissue.
EXAMPLE II
In this operation, freshly cut grass was combined with alkaline stabilized pasteurized sludge product in a 2:1 volume to volume ratio as illustrated in FIG. 3. This volume ratio represents a mass ratio of 1 pound of grass to 3 pounds of alkaline stabilized sludge product. The alkaline stabilized sludge product had been processed through the heat pulse stage and once-windrowed prior to use for this operation. A 2:1 volume ratio of grass to alkaline sludge product was previously shown to result in rapid lowering of pH of the blend. Previous work had also demonstrated that sufficient greenwaste must be added to generate enough acid-neutralizing power to rapidly shift the pH of the product of this invention to more neutral ranges required for accelerated biodegradation of the greenwaste, i.e., pH 7-9. This work also demonstrated that moisture content needs to be maintained at less than 50% to minimize the chances of the product of this invention becoming anaerobic and producing unwanted odors during the composting phase. The protocol required maintenance of the three treatments at 65%, 60% and 55% solids. The blends were process twice per week to mix, aerate and adjust the moisture content of the windrows. The alkaline stabilized sludge was initially high in pH (>12) with a medium density of microorganisms, i.e., 10 6 /gram dry weight and no detectable human pathogen indicator organisms (fecal coliforms). The grass greenwaste had a large standing crop of microorganisms, i.e., 10 8 /gram dry weight and a detectable number of pathogen indicator organisms, i.e., >10 5 /gram dry weight. One week after blending these two materials together, none of the treatments showed any remaining human pathogen-indicating organisms. All three treatments showed a gradual rise in total microorganism numbers. All treatments also showed a 3 log increase in gram positive microorganisms. After 7 weeks of processing over 99% of all recoverable organisms were gram positive. At the same time, combined gram negative, fecal streptococci, and fungi represented less than 0.1% of the total microflora indicating a major shift in populations from that found the alkaline stabilized sludge product alone.
All three samples underwent a drop in pH over the course of this study. Within two weeks, each treatment was about pH 9.0. Chemical oxygen demand (COD), a measure of available organic carbon, also dropped over the course of the operation for all three samples. The relationship of bacterial growth, as indicated by the rise in gram positive bacteria, to both pH and COD is represented in FIG. 5. It may be inferred from the data that a drop in pH to approximately pH9 is a prerequisite for the initial growth of gram positive bacteria, which, in turn, transform available organic carbon to energy and carbon dioxide. Thus, a gradual drop in COD over time reflects the growth and activity of gram positive bacteria. The dominance of gram positive bacteria over other microbial groups is expected for the optimal environment for the product of this invention which also includes an elevated temperature and about 55% solids. An indication of nutrient availability for microbiological growth is the initial increase in conductivity seen in the 55% solids treatment. This conductivity increase occurs in parallel with the initial log increase in gram positive bacteria and is possible due to the action of bacterial enzymes digesting the greenwaste and releasing nutrients for additional microbial growth. The conductivity increase clearly seen in FIG. 5 (triangles) is followed by a gradual decline over the course of weeks to original levels.
By keeping the percent solids within the 55% to 65% range, the product of this invention never became plastic or nongranular. This allowed for ease of windrowing and more efficient aeration. No septic conditions were detected throughout the course of the mixing and aeration. The grass in each treatment underwent physical transformation in less than three weeks. By that time in the process, the grass tissue was virtually indistinguishable in the blend. The further stabilization of the blends over ensuing weeks in indicated by the continual drop in COD which is a measure of organic carbon available for organism regrowth.
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The method of treating wastewater or bioorganic sludges containing odor, animal viruses, pathogenic bacteria, and parasites to produce a bioactive but stabilized product that is useful as a soil substitute or as a fertilizer which can be applied directly to lands which consists essentially of the following steps: mixing said sludge with at least one alkaline material, wherein the amount of added material mixed with said sludge is sufficient to raise the pH of said mixture to pH 12, and raise the conductivity to disinfect and stabilize the sludge, and adding green waste at different process locations so that a biological action occurs converting the greenwaste into a soil-like granular product with improved odor over that of the treated municipal sludge alone or a composted greenwaste alone.
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RELATED APPLICATION
[0001] This application claims benefit of U.S. provisional application Ser. No. 61/852,031, filed Mar. 15, 2013, entitled “Wastewater Treatment Apparatus And Process Therefor,” which application is incorporated herein in its entirety.
FIELD OF THE INVENTION
[0002] The present invention is directed to wastewater treatment plants and a new and unique apparatus and process for treating wastewater. More particularly, one preferred embodiment of the invention is directed to wastewater treatment utilizing channel plug flow dynamics with attached growth media and pure oxygen or mixtures of pure oxygen and compressed air.
BACKGROUND OF THE INVENTION
[0003] Biological wastewater treatment in the modern era has been accomplished by the cultivation of beneficial microorganisms being “grown” in a vessel, e.g. a tank, pond, lagoon (pond with mechanical mixers), etc., where the wastewater, such as domestic sewage, industrial wastewater, commercial wastewater, etc., can be introduced as a “food source” for the microbes. The microbes reduce the waste, i.e. the pollutants, resulting in an acceptable treated effluent, i.e. discharge water, which can be discharged to streams, rivers, bays, groundwater, or reuse applications such as landscape features, carwash water, irrigation, etc. The technology for this type of treatment has evolved exponentially in recent years due to the advancement of scientific and engineering understanding, more stringent environmental regulations, and economic advantages in the manufacturing sector. Perhaps most important in today's environment, there is a need to advance the usage of reclaimed water to offset a diminishing domestic water supply.
[0004] Early in the development of biological wastewater treatment, a simple pond or lagoon was utilized as a treatment process. Wastewater was contained after collection from, for example, a sewer network within a community, in the pond/lagoon where it was retained for several weeks. There, the inherent microbes would have a chance to reduce the waste allowing “treated” water to be discharged into a water body.
[0005] Later, in an effort to accelerate the process and provide a much smaller footprint for wastewater treatment plants (WWTPs), mechanical systems were developed to provide the necessary air and microbe manipulation to simulate what the sewer lagoons were doing in past years, only much faster and with a much smaller footprint. An advantage of these systems was the higher level of treatment provided and, therefore, a broader possibility of discharge locations. These systems were termed “activated sludge” treatment plants due to the microbes being “activated” by a high level of nutrients and carbon supplied by the wastewater thus allowing accelerated growth of the organisms resulting in a very high percentage of waste material removal. “Sludge” in this context is a coalescing of the microbes and not the waste itself. Treatment plants of this type could routinely remove 90-95% of the pollutants, i.e. organic matter, in the wastewater.
[0006] In approximately the last decade, modification of the activated sludge process has added another highly efficient method of removing the organic matter from wastewater utilizing the “attached growth process” in lieu of a suspended growth process. Thus, in the conventional activated sludge systems, the microbes and wastewater were mixed together in the vessel/tank, sometimes referred to as a reactor, along with aeration devices such as diffusers, mixers, etc., that would keep the water completely mixed allowing sufficient contact time for the microbes to do their job. The development of attached growth media systems supplemented the suspended growth process by the addition of “media” of some sort, such as polyethylene extruded polymer, similar to a plastic honeycomb, placed into the reactor to allow the microbes to attach themselves and grow rather than being suspended in the mixed water. This media has a high surface area to volume ratio allowing a lot of surface for the microbes to grow in a small volume of space. This has proven to be a good system for some applications.
[0007] While known WWTPs have been useful, there is a need for WWTPs for treating small flow, e.g. 100,000 gallons per day or less, and more preferably 50,000 gallons per day, having a small foot print and which is efficient in removing pollutants.
SUMMARY OF THE INVENTION
[0008] The invention is directed to a new apparatus and method using variations of the plug flow process, the attached growth media process and subjecting the wastewater to nearly pure oxygen (>90%) vs. air (19% O 2 ) or mixtures of pure oxygen and compressed air as discussed hereafter. Thus, the invention is a WWTP that uses continuous “channel” plug flow dynamics with attached growth media and pure oxygen as a source of required oxygen, or a combination of pure oxygen and compressed air.
[0009] Objects of the invention include, but are not limited to, the following: (a) a reduction in the retention time within the reactor by utilizing oxygen, thus a smaller footprint and smaller basin per gallon for treatment; (b) minimization of “washout” as with complete mix systems; (c) higher microbial populations, thus higher treatment efficiency; (d) higher reduction in recalcitrant organic compounds due to higher oxygen concentrations in the mixed liquor; (e) reduction of short-circuiting in the flow path as with complete mix systems; and (f) a more cost effective system in terms of space and usage. Places with smaller plots where space is at a premium, e.g. restaurants, carwashes, etc., will find the invention a more viable option than the known treatment processes. Additionally, offshore operations such as oil platforms and marine vessels will find the invention very useful given available space restrictions and the required effluent quality.
[0010] The present invention includes an apparatus for treatment of wastewater comprising a wastewater treatment tank for treating an influent wastewater and providing treated effluent discharge water. The tank may comprise a tank having a bottom wall, side walls, a first end wall, a second end wall and a cover providing access to the inside of the tank. The first end wall includes a means for receiving influent wastewater and the second end wall includes a means for discharging effluent treated discharge water. There are at least two baffles providing for at least three separate compartments in the tank adapted to provide for plug flow movement of the wastewater. The compartments may include attached growth media for treating the wastewater. There is an oxygen source or an oxygen and compressed air source connected to an air diffuser in each of the compartments for treating the water. The influent wastewater enters the tank through the first end wall and flows through the at least three compartments utilizing plug flow movement and is treated by the attached growth media and the oxygen or oxygen and compressed air to provide a treated effluent discharge water which exits the tank through the second end wall.
[0011] The present invention further includes a method of treating wastewater comprising pumping wastewater into a wastewater treatment tank. The wastewater treatment tank comprises at least two baffles providing for at least three separate compartments in the tank adapted to provide for plug flow movement of the wastewater. The compartments may include attached growth media for treating the wastewater. There is an oxygen source or an oxygen and compressed air source connected to an air diffuser in each of the compartments for treating the water. The influent wastewater enters the tank and flows through the at least three compartments utilizing plug flow movement and is treated by the attached growth media and the oxygen or oxygen and compressed air to provide a treated effluent discharge water which exits the tank.
[0012] These primary and other objects of the invention will be apparent from the following description of the preferred embodiments of the invention and from the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The following detailed description of the specific non-limiting embodiments of the present invention can be best understood when read in conjunction with the following drawings, where like structures are indicated by like reference numbers.
[0014] Referring to the drawings:
[0015] FIG. 1 is a perspective view of the apparatus of the present invention.
[0016] FIG. 2 is an end view of the influent end of the apparatus of FIG. 1 .
[0017] FIG. 3 is an end view of the effluent end of the apparatus of FIG. 1 .
[0018] FIG. 4 is a top view of the apparatus of FIG. 1 showing the inside of the apparatus with the growth media partially cut away in the first and third compartments and showing the wastewater flow (certain of the other components of the tank are not shown for ease of reference).
[0019] FIG. 5 is taken along line 5 - 5 of FIG. 4 showing an elevational view of a first baffle and an additional area for filtration or treatment of the treated water.
[0020] FIG. 6 is taken along line 6 - 6 of FIG. 4 showing an elevational view of a second baffle.
[0021] FIG. 7 is a top view of the apparatus of FIG. 1 with the growth media removed and showing the diffuser components of the tank.
[0022] FIG. 8 is taken along line 8 - 8 of FIG. 7 and shows an elevational view of the influent end of the tank of FIG. 1 showing the piping attached to the diffusers.
[0023] FIG. 9 is taken along line 9 - 9 of FIG. 6 and is a partial elevational view showing the outlet pipe.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The present invention is directed to the treatment of wastewater from various sources. The size and scale of the present invention will vary depending upon the amount of wastewater to be treated and the nature of the wastewater being treated. The present invention is useful for the treatment of wastewater from carwash facilities. The description of the present invention will be directed to a wastewater treatment plant for treatment of wastewater from carwash facilities. However, it is understood that the invention may be directed to a number of other wastewater treatment facilities, including as described in this application.
[0025] The wastewater treatment plant of the present invention includes a tank 10 . The tank includes side walls 12 and 14 , end walls 16 and 18 , a bottom 20 , and a top 21 . The top 21 includes a handles 21 a for opening the top via hinges as seen in FIG. 3 and there is a center support rail 21 b for the top members 21 . It is understood that the top remains closed in operation, and there is a gasket 23 (only partially shown in FIG. 4 ), preferably made of foam, surrounding the upper ends of the side and end walls to maintain the oxygen or oxygen and compressed air in the system. A preferred dimension for a WWTP 10 for treatment of wastewater from a carwash averaging about 3,000 gallons per day is approximately 6 feet in length, 3 feet in width and 4 feet in height, although these dimensions may vary without departing from the scope of the invention. The tank may include casters 25 and may be movable.
[0026] The tank 10 receives the wastewater from a carwash and provides for the treatment of the wastewater. The tank includes influent openings 22 in end wall 16 for receiving the wastewater and an effluent opening 24 in the end wall 18 for discharging the treated wastewater, i.e. pollutant-reduced water. The invention uses a plug flow process providing for a continuous path for the movement and the treatment of the wastewater as shown, for example, in FIG. 4 . The tank is divided by baffles 26 and 28 providing for separate compartments and a serpentine path for the continuous flow of the wastewater, i.e. plug flow movement of the wastewater. While a presently preferred embodiment includes two baffles 26 and 28 , a different number of baffles may be used without departing from the scope of the invention.
[0027] More specifically, referring to FIGS. 5 and 6 the baffles 26 and 28 will be described. FIG. 5 shows baffle 26 which extends vertically from the bottom 20 of tank 10 and includes an opening 40 for the water flow from the first compartment of the tank to the second compartment of the tank. Baffle 26 includes baffle extension members 50 and 52 which extend from side wall 16 to the wall 70 of compartment 34 and provide reinforcement for the tank sides. Additionally, baffle 26 includes support plates 29 which provides support for the growth media 30 . Such support plates 29 are in each compartment as shown in FIG. 7 .
[0028] Referring now to FIG. 6 , baffle 28 is described. Like baffle 26 , baffle 28 extends from the bottom 20 of the tank vertically close to the top portion of the tank. Baffle 28 includes opening 42 for the water flow. Like baffle 26 , there are baffle extensions 54 and 56 which provide support to the side walls. It is further noted that the side walls 12 and 14 also include similar extension members 58 and 60 providing means for attachment of plates 29 for support of growth media 30 and structural support for tank 10 . Similar to baffle 26 , there are also support plates 29 attached thereto and extending to the extension members in the side walls of the tank.
[0029] Referring now to FIG. 7 , there is shown diffuser members 36 . Diffuser members 36 are held on support plates 62 . In a preferred embodiment, EDI FlexAir™ “T” Series fine bubble tube diffusers 36 are used, manufactured by Environmental Dynamics Inc., Columbia Mo., although other brand diffusers are useful for air/O 2 diffusion and mixing provided the specifications are met. The diffuser members are connected to air supply members 46 . Referring to FIGS. 7 and 8 , the wastewater treatment plant may utilize pure oxygen fed from an oxygen generator (not shown) to input source 32 as the source of oxygen for the aerobic bacteria and other organisms in the oxidation of organic chemicals in various sources of wastewater. In the alternative, the plant may utilize pure oxygen and compressed air, the compressed air and pure oxygen being regulated in the specific amounts depending upon the wastewater being treated. The oxygen and compressed air is fed to a manifold 45 and distributed by pipes 46 , preferably made of PVC, to diffusers 36 . Diffusers 36 provide fine bubbles to accelerate the growth of the microbes for treating the wastewater.
[0030] Referring to FIG. 4 , the tank includes attached growth media 30 a, 30 b and 30 c for the treatment of the wastewater (media 30 a and 30 c being shown partially cut away). As stated above, the tank includes an input source 32 for introducing oxygen into the system for promoting the growth of organisms on the growth media 30 for treating the wastewater and removing pollutants from the wastewater. A presently preferred growth media is a polymer extrusion media made by Matala Water Technology of Taiwan. However, other manufacturers growth media may be used with the understanding that the proper surface to volume ratio and compatibility with wastewater specifications are met. The first approximately ⅓ of the flow length will contain the polymer media 30 a with a minimum surface to volume ratio of about 88 ft 2 /ft 3 followed by the next roughly ⅓ flow length containing polymer media 30 b with a minimum surface to volume ratio of about 111 ft 2 /ft 3 . The final roughly ⅓ of flow length, where polishing occurs, may have a polymer media 30 c having a minimum surface to volume ratio of about 140 ft 2 /ft 3 . The media density may be modified as needed for desired treatment results.
[0031] The hydraulic configuration of the tank is a continuous flow path, i.e. plug flow, with preferably a minimum length to width ratio through the reactor containing the media of about 8:1 depending on wastewater characteristics and composition. It is understood that this ratio may further be in the range of about 8:1 to about 12:1. The wastewater will flow through the reactor as a fixed film process utilizing a high surface area to volume media made from the growth media which will provide growth sites for the aerobic bacteria and other inherent organisms, or a bacteria “condominium” where they will grow and multiply thus reducing pollutants in the wastewater.
[0032] The tank includes an internal final compartment 34 where the reactor, i.e., aeration chambers or compartments, terminates to be used for installation of an additional filtration (e.g., ultra, nano, etc.) unit as needed. This compartment 34 is especially useful in meeting water reuse requirements, although it may be optional depending on required water quality. The final compartment can also be used for settling, disinfection, or chemical addition.
[0033] A preferred embodiment uses a tank constructed using 5/16 inch aluminum plate with welded joints and seams. Other materials may be utilized for the tank construction provided that the materials are compatible with the characteristics of the untreated wastewater and structurally capable of supporting the system components and weight of water, including aluminum, stainless steel, fiberglass, or any extruded polymer (e.g., plastic, high density polyethylene, etc.) The tank preferred preferably includes a member 37 to drain the water from all of the compartments.
[0034] The operation of the apparatus and method of the invention will now be described in relation to the drawings. Referring, for example, to FIG. 2 , there are two inlet openings 22 , e.g. a 1.75 inch diameter aluminum pipe fitting and a 1.25 inch diameter aluminum pipe fitting, for receiving the wastewater, in this example wastewater from a carwash using tank 10 as described above. The openings provide for receiving different size pump hoses. The wastewater from a carwash is pumped through one of openings 22 into tank 10 , preferably in the range of about two gallons to about six gallons per minute. Referring to FIG. 4 , the wastewater is approximately an inch above the growth media 30 and below baffles 26 and 28 . As stated, the growth media is preferably of different densities, the least dense being in the first compartment and the most dense being in the third compartment prior to overflow into the filtration/chemical addition compartment 34 . The water circulates from the first compartment through an opening 40 to the second compartment and circulates through the second compartment through an opening 42 to the third compartment. The circulation time may be in the range of about eight to 24 hours depending on the oxygen concentration utilized. Thereafter, the treated water is moved from the third compartment via overflow pipe 44 , as shown in FIGS. 8 and 9 , to the final compartment 34 for any additional treatment. Thereafter, the treated water is removed from the tank through effluent opening 24 . In this example, the wastewater is treated with pure oxygen entering from an oxygen source through pipe 32 and fed to a manifold 45 which feeds conduits 46 to the fine bubble diffusers 36 . This accelerates the growth of the microbes for treated the wastewater. It is understood that the rate of the oxygen feed may be varied thereby reducing or increasing the wastewater detention time in the tank. It is understood that instead of pure oxygen, a mixture of pure oxygen and compressed air may be used.
[0035] Accordingly, an objective of the present invention is a combination of nearly pure oxygen as an oxygen source or mixed as required with compressed ambient air with continuous plug flow hydraulics and attached growth media as the substrate for bacteria to attach and grow. This provides for a smaller footprint of the apparatus and process, thereby achieving lower costs, the ability to utilize the treated water in sustainable applications such as water reuse, and a more complete oxidation of pollutants. An additional advantage is the reduced waste sludge volume as found in conventional suspended growth complete mixed systems.
[0036] The invention may be used by entities requiring wastewater treatment with approximately less than 100,000 gallons per day of flow, and preferably about 50,000 gallons per day, including the carwash industry for treatment and/or reuse of wastewater from the facility, marine vessels and offshore oil platforms, remote land-based oil exploration sites, and any other commercial, industrial, and domestic applications requiring wastewater treatment.
[0037] The exemplary embodiments herein disclosed are not intended to be exhaustive or to unnecessarily limit the scope of the invention. The exemplary embodiments were chosen and described in order to explain the principles of the present invention so that others skilled in the art may practice the invention. As will be apparent to one skilled in the art, various modifications can be made within the scope of the aforesaid description. Such modifications being within the ability of one skilled in the art form a part of the present invention and are embraced by the appended claims.
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Wastewater treatment plants and processes for treating wastewater are described. The wastewater treatment plant utilizes channel plug flow dynamics with attached growth media and pure oxygen or mixtures of pure oxygen and compressed air.
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[0001] This nonprovisional application is a continuation of International Application No. PCT/EP2012/076855, which was filed on Dec. 21, 2012, and which claims priority to German Patent Application No. 10 2011 090 159.0, which was filed in Germany on Dec. 30, 2011, and which are both herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to a plate-type heat exchanger, particularly for motor vehicles, with a plurality of plate groups to form first and second and/or third flow paths, whereby a spatial region for the fourth flow paths is formed between adjacent plate groups.
[0004] 2. Description of the Background Art
[0005] Heat exchangers are provided in motor vehicles in a wide variety and for a multitude of different purposes. Thus, evaporators are used in climate control systems in order to cool the air by evaporation of the refrigerant in flow paths flowing through the evaporator, in order to bring about an air conditioning and dehumidification in the vehicle interior. Flat tube-type or plate-type evaporators have become known for this purpose.
[0006] In regard to motor vehicles, the main trend in recent times has been to reduce the fuel consumption of a motor vehicle and the CO 2 emissions associated therewith. This is also achieved in the case of motor vehicles with an internal combustion engine in that during temporary idling caused by stopping of the vehicle at a traffic light or in similar situations, for example, the vehicle's combustion engine is turned off. As soon as the vehicle is reactivated to drive by actuation of the gas pedal or the clutch pedal, the internal combustion engine is automatically restarted. This technology is also called the start-stop method. Such start-stop methods have already been implemented in low-consumption motor vehicles. For commercially available vehicle climate control systems with a cooling circuit according to the vapor compression cycle, the compressor of the cooling circuit is usually powered by a belt drive, driven by the vehicle's driving engine. When the engine is idle, i.e., when the compressor drive is not working, the climate control system can no longer be described as cold-producing. With a turned-off engine in the start-stop operation, the air conditioning of the motor vehicle can therefore no longer operate and provide a cooling capacity for cooling the vehicle's interior. As a consequence of this situation, the evaporator of the climate control system warms up relatively quickly and the air flowing through the evaporator is cooled only slightly or too little. For one thing this causes the interior vehicle temperature to rise and to affect the physical comfort of the vehicle passengers negatively.
[0007] Apart from the temperature reduction, a dehumidifying process also occurs in a vehicle climate control system, because the moisture in the air condenses in the evaporator and leaves the vehicle through a condensate outlet. The air flowing through the evaporator is therefore dehumidified and enters dehumidified the motor vehicle interior. In the case of the active start-stop operation, the dehumidification of the air entering the vehicle interior can thus no longer be sufficiently assured, so that the humidity in the vehicle interior increases during the active start-stop operation. This also results in an increase in humidity which is perceived as unpleasant and uncomfortable by the vehicle passengers.
[0008] In order to prevent or slow down these temperature- and humidity-increasing processes, the so-called storage evaporator was developed which, in addition to the actual evaporator function, also comprises a cold storage medium that removes heat from the air flowing through the evaporator in an active start-stop operation and continues to cool and dehumidify it.
[0009] These storage evaporators have been disclosed, for example, in DE 102006028017, which corresponds to U.S. Pat. No. 8,495,894, and which is incorporated herein by reference. The storage evaporator disclosed has two separate heat exchanger blocks, the evaporator and the storage section, which are produced in different production processes and are connected together just before the soldering process and are then soldered together to a unit. The main evaporator has two flat tube rows, arranged one behind the other in the air flow direction, and the storage section is connected downstream of these two flat tube rows in the air flow direction. The storage part has double-tube rows with two tubes being inserted into one another, whereby the refrigerant flows in the interior of the inner tube and the cold storage medium is disposed in the space between the outer tube and the inner tube.
[0010] However, in the conventional art, the corresponding production process is very complex and expensive, because many different parts have to be matched, joined, and calibrated in order to be able to produce a properly functioning heat exchanger. In particular, a double tube with covered tube entries proves to be relatively complex, the number of parts is very high with at the same time a high number of different parts and compliance with tolerances represents a risk for process capability due to the many structural parts. This in turn means an increased risk of leakage, so that apart from the parts costs the risk of the reject rates also increases.
SUMMARY OF THE INVENTION
[0011] It is therefore an object of the invention to provide a heat exchanger, which is simple to manufacture and results in lower costs than the heat exchangers known in the conventional art at a simultaneously reduced complexity and reduced rejection rate.
[0012] In an exemplary embodiment, a plate-type heat exchanger is provided, particularly for motor vehicles, with a plurality of plate groups to form first and second and/or third flow paths, whereby a spatial region for the fourth flow paths is formed between adjacent plate groups, the plate groups has at least one plate pair having a first and second plate to form the first flow paths and the second flow paths, whereby a third plate can be arranged in conjunction with one of the first or one of the second plates in order to form the third flow path. The plate-type design avoids the need for the insertion of flat tubes into one another, which simplifies the production process. The heat exchanger of the invention can provide a heat exchanger for a plurality of fluids participating in the heat transfer. Thus, a heat exchanger can be provided which can be operated as a storage evaporator, whereby in this heat exchanger refrigerant flows in the first and second flow path, a cold storage medium is provided in the third flow path, and the air to be cooled flows through the fourth flow path. As an alternative exemplary embodiment, however, a heater with a heat-storage unit can also be provided, where a heat-transporting fluid, such as, for example, a coolant of the internal combustion engine, flows in the first and second flow path, a heat storage medium is provided in the third flow path, and the air to be heated flows through the fourth flow path.
[0013] According to an embodiment of the invention, the plates of the heat exchanger can have at least in part openings and/or cups as connecting and interconnecting regions and have channel-forming structures, such as embossings, to form flow paths between connecting regions. These can preferably be produced by embossing or deep-drawing, so that both the cups are drawn from the flat plate or the flat strip and the channel-forming structures are embossed or drawn. With this process or tool the openings can also be stamped out.
[0014] The first plate of the plate group at two opposite end regions can have two connecting regions each as an inlet and/or outlet of the first and second flow path and a channel-forming structure is provided between each of the two connecting regions to form the first and second flow path, whereby, furthermore, two openings and/or cups are provided at opposite ends of the first plate for connection to the third flow path. A rectangular plate, for instance, is provided with two short and two long sides, whereby then advantageously the particular connecting regions of the first plate are arranged on the two opposite short sides. In this regard, the flow paths of the first and second structures formed as flow paths would then be directed, for instance, in the direction of the long sides. As a result, a relatively long first and second flow path for the flowing fluid, such as for the refrigerant, can be created and a shorter fourth flow path for the air. This reduces the pressure drop for air and the noise of the air in the evaporator.
[0015] The second plate of the plate group at two opposite end regions can have two connecting regions each as an inlet and/or outlet of the first and second flow path and a channel-forming structure between two connecting regions to form the first or second flow path, whereby, furthermore, two openings and/or cups are provided at opposite ends of the first plate for connection to the third flow path.
[0016] Also, no channel-forming structure or a volume-modified or reduced channel-forming structure can be formed between the two connecting regions of the second or first flow path. This is advantageous, so that the third flow path can be disposed in this region, without there being highly interfering effects of the first or second flow path.
[0017] A third plate can be connected to the second plate such that it is arranged in the plate region without a channel-forming structure or with a modified or reduced channel-forming structure and forms the third flow path and has openings and/or cups, which communicate with the openings and cups of the third flow path of the second plate as an inlet or outlet. This is advantageous because the third flow path can then be disposed in this region, without there being interfering effects of the first or second flow path.
[0018] The connecting and interconnecting regions of the three flow paths can be arranged such that a connecting and interconnecting region of each flow path is arranged substantially next to one another at an opposite end of the plate or plate group.
[0019] A connecting and interconnecting region of the third flow path can be arranged between the connecting and interconnecting regions of the first and second flow path. This permits a uniform arrangement of connections, because the connection of the third flow channel can thus be kept smaller than the connection of the two other flow channels.
[0020] A connecting and interconnecting region of the third flow path can be arranged next to connecting and interconnecting regions of the first and second flow path.
[0021] The cup-shaped connecting and interconnecting regions and/or the channel-forming structures of the first and/or second and/or third plate can be made equally deep relative to the first and/or second and/or third flow channel in the direction perpendicular to the plane of the plate. This permits the flow channels in their depth to be adapted to requirements, so that, for example, the first and second flow channels can be designed with a similar flow cross section.
[0022] The cup-shaped connecting and interconnecting regions and/or the channel-forming structures of the first and/or second and/or third plate in regard to the first and/or second and/or third flow channel can be formed in a direction perpendicular to the plane of the plate such that the depth of the channel-forming structures of the first plate is greater or smaller than the depth of the channel-forming structures of the second and/or third plate in regard to the second and third flow path. This permits the flow channels in their depth to be adapted to requirements, so that, for example, the first and second flow channels can be designed with a greater flow cross section than the third flow channels.
[0023] Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:
[0025] FIG. 1 illustrates a first exemplary embodiment of a heat exchanger of the invention;
[0026] FIG. 2 illustrates a view of a detail enlargement according to FIG. 1 ;
[0027] FIG. 3 illustrates a view of a plate arrangement of a heat exchanger;
[0028] FIG. 4 illustrates a view of a plate arrangement of a heat exchanger;
[0029] FIG. 5 illustrates a view of a plate arrangement of a heat exchanger;
[0030] FIG. 6 illustrates a view of a plate arrangement of a heat exchanger;
[0031] FIG. 7 illustrates a view of a plate arrangement of a heat exchanger;
[0032] FIG. 8 illustrates a view of a plate arrangement of a heat exchanger;
[0033] FIG. 9 illustrates a view of a plate arrangement of a heat exchanger;
[0034] FIG. 10 illustrates a view of a plate arrangement of a heat exchanger;
[0035] FIG. 11 illustrates a view of a plate arrangement of a heat exchanger in a sectional illustration;
[0036] FIG. 12 illustrates a view of a plate arrangement of a heat exchanger in a sectional illustration;
[0037] FIG. 13 illustrates a view of a plate arrangement of a heat exchanger in a sectional illustration;
[0038] FIG. 14 a view of a plate arrangement of a heat exchanger in a sectional illustration;
[0039] FIG. 15 illustrates a view of a plate arrangement of a heat exchanger in a sectional illustration; and
[0040] FIG. 16 illustrates a view of a plate arrangement of a heat exchanger in a sectional illustration.
DETAILED DESCRIPTION
[0041] FIG. 1 shows a heat exchanger 1 with a first top header 2 and a second bottom header 3 , which are arranged at two opposite ends of the heat exchanger and extend in a transverse direction, and having a block 4 , in which the block network includes plates that are joined together to form plate groups, a plurality of plate groups 5 being arranged next to one another in order to form the heat exchanger network. Spatial regions 6 , which are used for the flow of air through the heat exchanger, for example, are provided between two adjacent plate groups 5 . The air flow direction is indicated by arrow 26 . Fins such as, for example, corrugated fins can also be provided in the indicated spatial regions to improve the heat transfer.
[0042] It is evident that the top and bottom headers have substantially three flow channels, which are indicated by the three connecting pieces 7 , 8 , 9 . These flow channels of the header extend in the transverse direction at the top side and at the bottom side of the heat exchanger. Flow channels, which divide into first, second, and third flow channels 10 , 11 , 12 , are provided between the headers. Flow channels 12 are formed between opposite connecting regions 8 , flow channels 11 are formed between opposite connecting regions 9 , and flow channels 10 are formed between opposite connecting regions 7 .
[0043] As is evident in FIG. 3 , a plate group has a first plate 13 , a second plate 14 , and a third plate 15 . First plate 13 , also evident in FIG. 4 , has three connecting and interconnecting regions 7 , 8 , 9 at its top narrow side, whereby these connecting and interconnecting regions are also arranged at the bottom opposite narrow side of plate 13 . In this case, connecting and interconnecting regions 7 and 9 are formed as cups projecting out of the plane of the plate in a direction oriented perpendicular thereto. Connecting and interconnecting regions 8 can advantageously also be formed as cups, but also as openings without cups, as is evident in FIG. 3 or in FIG. 4 .
[0044] Channel-forming structures 16 , 17 , which connect the cup-shaped connecting and interconnecting regions to a flow channel, are provided between connecting and interconnecting regions 7 or 9 at the top and bottom end region of a plate. Here, channel-forming structure 16 forms a first flow channel and channel-forming structure 17 a second flow channel. As is evident, second plate 14 also has two cups 18 , 19 at the top and bottom end region of the short sides, whereby furthermore an opening 25 is provided for the flow of a third medium through a third flow channel. Connecting and interconnecting regions 18 of second plate 14 are in turn connected together by means of a channel-forming structure 20 . Channel-forming structure 20 works together with channel-forming structure 16 in the case of connected first and second plates 13 , 14 , in order to form a first flow channel. With the two plates 13 and 14 connected to one another, a first flow channel arises formed by channel-forming structures 16 and 20 , and a second flow channel is formed by channel-forming structure 17 . It follows that in connecting the two plates 13 , 14 , the first flow channel has a greater depth perpendicular to the plate plane than the second flow channel. The first flow channel is therefore formed by the channel-forming structures, such as embossings 16 and 20 , with the second flow channel being formed solely by channel-forming structure 17 , because no channel-forming structure is provided in the second plate between cups 19 . The channel-forming structures are preferably embossings in the plate, resulting in indentations and thereby channels.
[0045] It can also be seen that a further plate 15 is placed on second plate 14 and is connected sealingly to it. Plate 15 with plate 14 in its flat region thereby forms flow channel 17 , because flow channel 17 is formed between the top connection and bottom connection 22 with plate 15 being arranged on the planar region 21 provided on second plate 14 . Connecting region 22 of plate 15 , formed as a cup or passage, for example, is arranged such that it aligns with opening 25 and opening 8 of the first or second plate in the horizontal direction, for instance.
[0046] As can be seen, first plate 13 and second plate 14 have a projecting circumferential edge, by means of which the two plates can be soldered sealingly to one another. Plate 15 also has a circumferential edge 23 , by means of which plate 15 can be soldered onto planar region 21 of plate 14 .
[0047] FIG. 3 shows how first plate 13 , second plate 14 , and third plate 15 can be arranged relative to one another and also can be connected to one another.
[0048] FIG. 4 shows a plate group having a first, second, and third plate 13 , 14 , 15 connected to one another, whereby the left half of the figure shows the plate group from the side of second and third plate 14 , 15 , whereas in the right half of the figure the plate group can be viewed from first plate 13 outward.
[0049] FIG. 5 shows the sequential arrangement of three plate groups having first, second, and third plates 13 , 14 , 15 , with the front view corresponding to first plate 13 , and plate 14 being arranged connected thereto, and of plate 15 only cup 22 can be seen as a passage.
[0050] FIG. 5 shows the arrangement of the connection of the cups of plates 13 and 14 , which soldered one onto the other project from plate pair 13 , 14 , whereby adjacent plate pairs 13 , 14 are soldered fluid-tight adjoining one another with these cups. Connecting cups 22 are arranged between cups 7 and 9 , whereby these are formed deeper in the axial direction than cups 7 , 9 of the first plate and cups 18 , 19 of the second plate, while the first plate has no cup in the area of passage 8 . Therefore, cup 22 of the third plate must substantially have the sum of the depths of cups 7 and 18 or 9 and 19 .
[0051] FIG. 6 shows the arrangement of three plate groups having first plates 13 , second plates 14 , and third plates 15 , whereby of third plates 15 only passages 22 can be seen in each case.
[0052] The two first and second plates 13 , 14 lie against one another with their circumferential edges. Passages 7 , 9 of the first plate are embossed forwards, whereby passages 22 of the third plate are embossed toward the back. The backward protruding passages or cups of second plate 14 , which cannot be seen in this perspective view, however, lie between these. It is clear, however, that the passages or cups 22 are at twice the height as the refrigerant cups. FIG. 4 shows that the backward protruding cups 22 of third plate 15 are approximately at twice the height as the cups of first and second plate 13 , 14 .
[0053] It is also evident that the channel-forming structures of first plate 13 , 16 proceeding from cups 7 , 9 expand to approximately half the width of the first plate and in the area of opening 8 of the first plate have a gusset-like recess, so that in this area soldering of first plate 13 to the cup of third plate 15 may be provided.
[0054] FIGS. 7 to 10 show the design of the first, second, or third plates 13 , 14 , 15 in two different variants, whereby in FIGS. 7 and 8 the cups of first, second, and third plate 13 , 14 , 15 have the same depth or length, and in the exemplary embodiment of FIGS. 9 and 10 cup 22 of third plate 15 has twice the depth of cups 7 , 9 of first and second plate 13 , 14 , whereby the first plate in the connection area of the third plate has no cup. Here, cups 7 , 9 have the same depth as cup 24 of third plate 15 . It can be seen in FIG. 9 that cup 7 and cup 9 have approximately only half the depth of cup 22 of third plate 15 .
[0055] FIGS. 11 to 14 show cuts through the plate groups, whereby FIGS. 11 and 12 show a cut through a plate group, which occurs in FIG. 7 or 9 approximately in the middle of cups 7 , 9 along line I-I, whereby this cut is made below cup 22 or 24 .
[0056] FIG. 11 shows the arrangement of three plate groups having a first plate 13 , a second plate 14 , and a third plate 15 in a side view from which the second plate and the third plate can be recognized. Three such plate groups are shown with connection of the cups of the plates to one another. It can be seen that cups 7 , 9 of the first plate have substantially the same depth as cups 18 , 19 of the second plate. The cup of the third plate cannot be seen. Here, only an area of channel-forming structure 15 of the third plate is visible.
[0057] FIG. 12 shows the same configuration of plates 13 , 14 , 15 as FIG. 11 , but only from the other side, so that in FIG. 12 the view is of first plate 13 as it were. FIGS. 13 and 14 show a cut through a plate arrangement according to FIG. 9 but at the height of the middle of passage 22 according to line II-II.
[0058] This cut occurs somewhat further above in comparison with the cut indicated by line I-I, so that now the three plate groups are cut and shown in the middle of cup 22 . It can be clearly seen that cup 22 has twice the depth in comparison with cups 19 or 9 or 7 and 18 . Therefore no cup is arranged on the side opposite to cup 22 of plate 13 , so that the far end of cup 22 on the opposite side touches first plate 13 directly without interconnection of a corresponding cup.
[0059] The absence of the cup on the sides of first plate 13 can be clearly seen in FIG. 14 .
[0060] FIGS. 15 and 16 show a cut through the arrangement of the plate groups according to FIG. 6 , whereby the plate groups are cut in the center of the plates. FIG. 6 shows a section of FIG. 5 with respect to an area in the middle of a plate group.
[0061] FIG. 15 shows the plate group from the side of first plate 13 , provided on the back with plate 14 , and onto the right side of which a plate 15 is again applied. First flow path 30 is formed between channel-like structure 31 of plate 13 and the channel-like structure 32 of plate 14 . Second flow path 33 is formed by channel-like structure 34 of plate 13 and planar plate surface 35 of the second plate. The second plate is preferably planar in this region but can also assume a specific structure.
[0062] Third flow path 36 is formed by wall 35 of the second plate and channel-like structure 37 of third plate 15 .
[0063] As can be seen in FIG. 16 , first flow path 30 is arranged between the first and second plate. Adjacent thereto, second flow path 33 is also arranged between the first and second plate, whereby third flow path 36 is arranged between the second plate and third plate. The expansion of the first flow path corresponds substantially to the expansion of the second flow path plus the expansion of the third flow path plus the thickness of the wall of the second plate.
[0064] In the present exemplary embodiment of FIGS. 9 and 10 with extended passage 22 of plate 15 , it can be seen that section 99 in plate 13 is greater than the diameter of passage 22 , so that upon soldering of two plate groups 13 , 14 , 15 one on top of the other, passage 22 does not come into contact with plate 13 but with plate 14 , onto which plate 15 is soldered from the other side. As a result, in the case of leakage between the soldered plates in the area of passage 22 , it occurs only between the channel between plates 14 and 15 and the outer area, without the other channels being involved and adversely affected.
[0065] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.
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A plate-type heat exchanger, in particular for motor vehicles, is provided that includes a plurality of plate groups in order to form first and second and/or third flow paths, a spatial region for fourth flow paths being formed between adjacent plate groups, the plate groups having at least one plate pair having a first and second plate in order to form the first flow paths and the second flow paths, wherein a third plate can be arranged in interaction with one of the first or one of the second plates in order to form the third flow path.
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RELATED REFERENCES
This application is a continuation of application Ser. No. 09/669,344, filed Sep. 26, 2000 now U.S. Pat. No. 6,531,238.
BACKGROUND OF THE INVENTION
The present invention relates in general to the field of proton exchange membrane (“PEM”) fuel cell systems, and more particularly, to an improved PEM fuel cell system having improved discrete fuel cell modules with improved mass transport for ternary reaction optimization and a method for manufacturing same.
A fuel cell is an electrochemical device that converts fuel and oxidant into electricity and a reaction by-product through an electrolytic reaction that strips hydrogen molecules of their electrons and protons. Ultimately, the stripped electrons are collected into some form of usable electric current, by resistance or by some other suitable means. The protons react with oxygen to form water as a reaction by-product.
Natural gas is the primary fuel used as the source of hydrogen for a fuel cell. If natural gas is used, however, it must be reformed prior to entering the fuel cell. Pure hydrogen may also be used if stored correctly. The products of the electrochemical exchange in the fuel cell are DC electricity, liquid water, and heat. The overall PEM fuel cell reaction produces electrical energy equal to the sum of the separate half-cell reactions occurring in the fuel cell, less its internal and parasitic losses. Parasitic losses are those losses of energy that are attributable to any energy required to facilitate the ternary reactions in the fuel cell.
Although fuel cells have been used in a few applications, engineering solutions to successfully adapt fuel cell technology for use in electric utility systems have been elusive. The challenge is for the generation of power in the range of 1 to 100 kW that is affordable, reliable, and requires little maintenance. Fuel cells would be desirable in this application because they convert fuel directly to electricity at much higher efficiencies than internal combustion engines, thereby extracting more power from the same amount of fuel. This need has not been satisfied, however, because of the prohibitive expense associated with such fuel cell systems. For example, the initial selling price of the 200 kW PEM fuel cell was about $3500/kW to about $4500/kW. For a fuel cell to be useful in utility applications, the life of the fuel cell stack must be a minimum of five years and operations must be reliable and maintenance-free. Heretofore known fuel cell assemblies have not shown sufficient reliability and have disadvantageous maintenance issues. Despite the expense, reliability, and maintenance problems associated with heretofore known fuel cell systems, because of their environmental friendliness and operating efficiency, there remains a clear and present need for economical and efficient fuel cell technology for use in residential and light-commercial applications.
Fuel cells are usually classified according to the type of electrolyte used in the cell. There are four primary classes of fuel cells: (1) proton exchange membrane (“PEM”) fuel cells, (2) phosphoric acid fuel cells, and (3) molten carbonate fuel cells. Another more recently developed type of fuel cell is a solid oxide fuel cell. PEM fuel cells, such as those in the present invention, are low temperature low pressure systems, and are, therefore, well-suited for residential and light-commercial applications. PEM fuel cells are also advantageous in these applications because there is no corrosive liquid in the fuel cell and, consequently, there are minimal corrosion problems.
Characteristically, a single PEM fuel cell consists of three major components—an anode gas dispersion field (“anode”); a membrane electrode assembly (“MEA”); and a cathode gas and liquid dispersion field (“cathode”). As shown in FIG. 1 , the anode typically comprises an anode gas dispersion layer 502 and an anode gas flow field 504 ; the cathode typically comprises a cathode gas and liquid dispersion layer 506 and a cathode gas and liquid flow field 508 . In a single cell, the anode and the cathode are electrically coupled to provide a path for conducting electrons between the electrodes through an external load. MEA 500 facilitates the flow of electrons and protons produced in the anode, and substantially isolates the fuel stream on the anode side of the membrane from the oxidant stream on the cathode side of the membrane. The ultimate purpose of these base components, namely the anode, the cathode, and MEA 500 , is to maintain proper ternary phase distribution in the fuel cell. Ternary phase distribution as used herein refers to the three simultaneous reactants in the fuel cell, namely hydrogen gas, water vapor and air. Heretofore known PEM fuel cells, however, have not been able to efficiently maintain proper ternary phase distribution. Catalytic active layers 501 and 503 are located between the anode, the cathode and the electrolyte. The catalytic active layers 501 and 503 induce the desired electrochemical reactions in the fuel cell. Specifically, the catalytic active layer 501 , the anode catalytic active layer, rejects the electrons produced in the anode in the form of electric current. The oxidant from the air that moves through the cathode is reduced at the catalytic active layer 503 , referred to as the cathode catalytic active layer, so that it can oxidate the protons flowing from anode catalytic active layer 501 to form water as the reaction by-product. The protons produced by the anode are transported by the anode catalytic active layer 501 to the cathode through the electrolyte polymeric membrane.
The anode gas flow field and cathode gas and liquid flow field are typically comprised of pressed, polished carbon sheets machined with serpentine grooves or channels to provide a means of access for the fuel and oxidant streams to the anode and cathode catalytic active layers. The costs of manufacturing these plates and the associated materials costs are very expensive and have placed constraints on the use of fuel cells in residential and light-commercial applications. Further, the use of these planar serpentine arrangements to facilitate the flow of the fuel and oxidant through the anode and cathode has presented additional operational drawbacks in that they unduly limit mass transport through the electrodes, and therefore, limit the maximum power achievable by the fuel cell.
One of the most problematic drawbacks of the planar serpentine arrangement in the anode and cathode relates to efficiency. In conventional electrodes, the reactants move through the serpentine pattern of the electrodes and are activated at the respective catalytic layers located at the interface of the electrode and the electrolyte. The actual chemical reaction that occurs at the anode catalyst layer is: H 2→ 2H + +2e − . The chemical reaction at the cathode catalyst layer is: 2H + +2e − +½O 2→ H 2 O. The overall reaction is: H 2 +½O 2→ H 2 O. The anode disburses the anode gas onto the surface of the active catalyst layer comprised of a platinum catalyst electrolyte, and the cathode disburses the cathode gas onto the surface of the catalytic active layer of the electrolyte. However, when utilizing a conventional serpentine construction, the anode gas and the cathode gas are not uniformly disbursed onto the electrolyte. Nonuniform distribution of the anode and cathode gas at the membrane surface results in an imbalance in the water content of the electrolyte. This results in a significant decrease in efficiency in the fuel cell.
The second most problematic drawback associated with serpentine arrangements in the electrodes relates to the ternary reactions that take place in the fuel cell itself. Serpentine arrangements provide no pressure differential within the electrodes. This prohibits the necessary ternary reactions from taking place simultaneously. This is particularly problematic in the cathode as both a liquid and a gas are transported simultaneously through the electrode's serpentine pattern.
Another shortcoming of the conventional serpentine arrangement in the anode in particular is that the hydrogen molecules resist the inevitable flow changes in the serpentine channels, causing a build-up of molecular density in the turns in the serpentine pattern, resulting in temperature increases at the reversal points. These hot spots in the serpentine arrangement unduly and prematurely degrade the catalytic active layer and supporting membrane.
In the typical PEM fuel cell assembly, a PEM fuel cell is housed within a frame that supplies the necessary fuel and oxidant to the flow fields of the fuel cell. These conventional frames typically comprise manifolds and channels that facilitate the flow of the reactants. However, usually the channels are not an integral part of the manifolds, which results in a pressure differential along the successive channels. FIG. 2 is an illustration of a conventional frame for the communication of the reactants to a fuel cell. This pressure differential causes the reactants, especially the fuel, to be fed into the flow fields unevenly, which results in distortions in the flow fields causing hot spots. This also results in nonuniform disbursement of the reactants onto the catalytic active layers. Ultimately, this conventional method of supplying the necessary fuel and oxidant to a fuel cell results in a very inefficient process.
As a single PEM fuel cell only produces about 0.30 to 0.90 volts D.C. under a load, the key to developing useful PEM fuel cell technology is being able to scale-up current density in individual PEM cell assemblies to produce sufficient current for larger applications without sacrificing fuel cell efficiency. Commonly, fuel cell assemblies are electrically connected in nodes that are then electrically connected in series to form “fuel cell stacks” by stacking individual fuel cell nodes. Two or more nodes can be connected together, generally in series, but sometimes in parallel, to efficiently increase the overall power output.
Conventional PEM fuel stacks often flood the cathode due to excess water in the cathode gas flow field. Flooding occurs when water is not removed efficiently from the system. Flooding is particularly problematic because it impairs the ability of the reactants to adequately diffuse to the catalytic active layers. This significantly increases the internal resistance of the cathode which ultimately limits the cell voltage potential. Another problem is dehydration of the polymeric membranes when the water supply is inadequate. Insufficient supply of water can dry out the anode side of the PEM-membrane electrolyte, causing a significant rise in stack resistance and reduced membrane durability.
Further, conventional PEM fuel cells and stacks of such fuel cell assemblies are compressed under a large load in order to ensure good electrical conductivity between cell components and to maintain the integrity of compression seals that keep various fluid streams separate. A fuel cell stack is usually held together with extreme compressive force, generally in excess of 40,000 psi, using compression assemblies, such as tie rods and end plates. If tie rods are used, the tie rods generally extend through holes formed in the peripheral edge portion of the stack end plates and have associated nuts or other fastening means assembling the tie rods to the stack assembly to urge the end plates of the fuel stack assembly toward each other. Typically, the tie rods are external, i.e., they do not extend through the fuel cell electrochemically active components. This amount of pressure that must be used to ensure good electrochemical interactions presents many operational difficulties. For example, if the voltage of a single fuel cell assembly in a stack declines significantly or fails, the entire stack must be taken out of service, disassembled, and repaired, resulting in significant repair costs and down-time. Second, inadequate compressive force can compromise the seals associated with the manifolds and flow fields in the central regions of the interior distribution plates, and also compromise the electrical contact required across the surfaces of the plates and MEAs to provide the serial electrical connection among the fuel cells that make up the stack. Third, the extreme compressive force used unduly abrades the surfaces of the fuel cell modules within the stack, resulting in wear of components in the fuel cell assemblies such as the catalyst layers of the electrolyte, thereby leading to increased losses in fuel cell stack and fuel cell assembly efficiency.
SUMMARY OF THE INVENTION
Accordingly, there is a need for an economical and efficient fuel cell assembly and fuel cell stack assembly with an optimized supply and mass transport system. Herein provided are improvements to the anode gas flow field and the cathode gas and liquid flow field. Further, maintenance and inspection of the fuel cell system of the present invention are less burdensome as very little compressive force is needed to ensure good electrochemical connection, enabling these fuel cell systems to be used effectively in residential and light-commercial applications. As a result, significant improvement in power density, efficiency, and life of the fuel cell are provided at the cell and stack level.
In one embodiment, the present invention comprises an improved gas flow field for a fuel cell assembly comprising a three-dimensional open cell foamed structure suitable for gas diffusion. In another embodiment, a method for making a three-dimensional open-cell foamed gas flow field is disclosed. Another embodiment of the present invention comprises a PEM fuel cell assembly having gas diffusion layer, gas and liquid diffusion layer, an anode gas flow field, and a cathode gas and liquid flow field. In still another embodiment, an improved fuel cell stack assembly is disclosed wherein the fuel cell assemblies of the stack comprise an open-cell foamed gas flow field and an open-cell foamed gas and liquid flow field. The present invention also provides for improved distribution for a fuel cell assembly providing for improved transport of the reactants to the fuel cell.
One advantage of the present invention is that these improvements increase the life and decrease the maintenance operations for a fuel cell. This enables the fuel cells to be used in residential and light-commercial applications effectively.
Another advantage is that the invention achieves optimal mass transport through the open cell foamed flow fields and the distribution frame of the present invention. This increases the overall efficiency and maximum power achievable by the fuel cell. Further, the anode gas and cathode gas are uniformly disbursed on the catalytic active layers of the electrolyte, resulting in optimal water balance in the fuel cell system. Flooding and drying out of the electrolyte are thereby avoided. In addition, hot spots that distort the fuel cell, resulting in maintenance to replace the damaged cell, are avoided. Maximum power is, thus, achievable.
Other advantages of the present invention will be apparent to those ordinarily skilled in the art in view of the following specification claims and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the present embodiments and advantages thereof may be acquired by referring to the following description taken in conjunction with the accompanying drawings, in which like numbers indicate like features, and wherein:
FIG. 1 is a schematic of a typical PEM fuel cell assembly.
FIG. 2 is an illustration of a conventional frame for housing and supplying reactants to a fuel cell assembly.
FIG. 3 is a depiction of a distribution frame of the present invention housing a fuel cell assembly.
FIG. 4 is an exploded view of the distribution frame and a fuel cell assembly of the present invention.
FIG. 5 is a cross-sectional view of an internal foil assembly of the present invention.
FIG. 6 is an electron micrograph of a three-dimensional open-cell foamed cathode gas and liquid flow field with microchannels.
FIG. 6A is an electron micrograph of the three-dimensional open-cell foamed cathode gas and liquid flow field with microchannels of the present invention magnified 10 times.
FIG. 6B is an electron micrograph of the three-dimensional open-cell foamed cathode gas and liquid flow field with microchannels of the present invention magnified 20 times.
FIG. 7 is an electron micrograph of the connections between a three-dimensional open-cell foamed gas flow field and an internal foil in an internal foil assembly of the present invention.
FIG. 8 is an electron micrograph of the connections between the three-dimensional open-cell foamed gas flow field magnified 150 times.
FIG. 9 is an electron micrograph of two individual connections between the three-dimensional open-cell foamed gas flow field and the internal foil of an internal foil assembly of one embodiment of the present invention.
FIG. 10 is an electron micrograph of a conventional internal foil assembly formed using conventional techniques.
FIG. 11 is an illustration of the fuel side of a distribution frame for a fuel cell assembly of the present invention.
FIG. 12 is an illustration of the air side of a distribution frame for a fuel cell assembly of the present invention.
FIG. 13 is an illustration of a fuel cell stack assembly of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 3 depicts one embodiment of an individual fuel cell assembly of the present invention. As shown in FIG. 3 , fuel cell 11 is housed within distribution frame 10 . Distribution frame 10 not only houses fuel cell 11 , but also facilitates transportation of the fuel and the oxidant to the fuel cell necessary for the electrochemical exchange in the fuel cell. This individual fuel cell assembly can be combined with other fuel cell assemblies to form a fuel cell node, and ultimately a stack assembly, to provide higher voltages and current for power generation. Of note in FIG. 3 are fuel inlet 22 , fuel inlet 24 , air inlet 12 and air and water outlet 14 . The fuel inlets 22 and 24 , air inlet 12 , and air and water outlet 14 are apertures in the distribution frame extending completely through the distribution frame, and run perpendicular, or at 90° angles, from one another in the distribution frame to facilitate the efficient flow of the fuel and oxidant to and through the anode gas and liquid flow field and cathode gas flow field, respectively.
FIG. 4 more particularly illustrates the component parts of the fuel cell assembly of one embodiment of the present invention depicted in FIG. 3 , specifically distribution frame 10 , primary internal foil assembly 64 , fuel cell 11 and secondary internal foil assembly 30 . Primary internal foil assembly 64 consists of primary anode gas flow field 52 , primary internal foil 54 and primary cathode gas and liquid flow field 56 . Primary internal foil 54 serves as a boundary layer between primary anode gas flow field 52 and primary cathode gas and liquid flow field 56 to keep air from flowing into the anode gas flow field from the cathode and water from flowing from the cathode gas and liquid flow field to the anode gas flow field. MEA 58 is composed of an electrolyte, primary cathode catalytic active layer 60 , and secondary anode catalytic active layer 62 . Any known MEAs may be used in the present invention. Conventional fluorocarbon based polymeric membranes are particularly suitable for the present invention-including Nafion membranes. Primary cathode catalytic active layer 60 is bonded to primary cathode gas and liquid flow field 56 when the fuel cell is assembled. Secondary internal foil 31 also serves as a boundary layer between the anode and cathode electrodes of the internal foil assembly as does primary internal foil 54 . Secondary anode catalytic active layer 62 is bonded to secondary anode gas flow field 29 when the fuel cell assembly is assembled. FIG. 4 illustrates the assembled fuel cell placed in distribution frame 10 wherein secondary cathode gas flow field 28 is in view. Secondary internal foil 31 is also illustrated in FIG. 3 .
When the fuel cell assembly of the present invention is assembled as in the embodiments depicted in FIGS. 3 and 4 , the procession of layers is: primary anode gas flow field 52 , primary internal foil 54 , primary cathode gas flow field 56 , MEA 58 , secondary anode gas flow field 29 , secondary internal foil 31 , and secondary cathode gas flow field 28 . This defines the elements of one fuel cell of the present invention terminated by internal foil assemblies. Primary cathode catalyst layer 60 and secondary anode catalyst layer 62 of the MEA shown in FIG. 4 may be comprised of platinum or a platinum/ruthenium catalyst. If platinum is used, it is typically combined with fibrous material, including suitable nonwovens, or suitable cotton muslin sheets or pieces of fabric. Primary cathode gas flow field 56 and secondary anode gas flow field 29 are bonded to primary cathode catalytic active layer 60 and secondary anode catalytic active layer 62 , respectively, through mechanical bonding means such as compression or adhesion. However, there is no need for excessive compressive force in the present invention to create the electrochemical connections between the catalytic active layers and the gas flow fields. Compression may be provided by any known means, such as a tie-rod assembly. In general, the compressive force on a fuel cell stack should be less than 100 psi.
FIG. 5 is a cross-section of an internal foil assembly of the present invention. Internal foil assembly 64 is comprised of three parts: anode gas flow field 66 , internal foil 68 , and cathode gas and liquid flow field 70 . The cross section of the anode gas flow field 66 may be preferably approximately half the size of cathode gas and liquid flow field 70 to accommodate the ratios of reactants necessary for the electrochemical exchange in the fuel cell. Both anode gas flow field 66 and cathode gas and liquid flow field 70 may be composed of a three-dimensional open-cell foamed structure suitable for gas diffusion that, preferably, may be plated with gold. In another embodiment of the present invention, cathode gas flow field 70 may be corrugated to create microchannels. FIG. 6 illustrates a corrugated cathode gas and liquid flow field of the present invention. These microchannels facilitate the removal of free water and excessive heat from the fuel cell assembly. When the fuel cell is placed in the distribution frame, these microchannels in the cathode gas and liquid flow field 70 run parallel to the air inlet and air and water outlet, and perpendicular to the fuel inlets. The vertical distance between the peak of a corrugation and the trough next to it, herein referred to as the pitch, should be at least ⅔ of the horizontal distance between a peak of one corrugation to the peak of the next corrugation, herein referred to as the run. Whereas, as shown in FIG. 5 , anode gas flow field 66 is directly bonded to internal foil 68 ; in an alternative embodiment cathode gas and liquid flow field 70 is only bonded to the internal foil at the peaks of the corrugations. As shown in FIG. 6 , the cathode gas and liquid flow field is therefore intermittently bonded to the internal foil at the peaks of the microchannels. This structure effectively manages the ternary reactions necessary for fuel cell operability by adequately removing the water and facilitating the movement of hydrogen and air. FIGS. 6A and 6B depict magnified views of the microchannels shown in FIG. 6 .
Suitable construction materials for the three-dimensional open-cell foamed gas flow fields and gas and liquid flow fields are conducive to flow distribution and possess good electrical conductivity properties. These may include: plastics, carbon filament, stainless steel and its derivatives, epitaxial substrates, nickel and its alloys, gold and its alloys, and copper and its alloys. Iridium may also be used if it has sufficient electrochemical properties. In one embodiment of the present invention, the anode gas flow field and the cathode gas and liquid flow fields are made from open-cell foamed nickel. The open-cell foamed nickel flow fields are produced by electroplating nickel over a particulate plastic so that the voids created by the tangential intersections in the particulate plastic structure are filled with nickel. Although polystyrene may be used in this method of producing the foamed flow field structure, other materials, such as other particulate thermoplastic resinous materials, would also be suitable in this process. Another suitable material, for example, would be Isinglass. If nickel is used, the nickel may be enhanced with 2.0% by weight of cobalt. The addition of cobalt enhances the mechanical strength of the nickel and reduces the drawing properties of the nickel. The addition of cobalt also strengthens the lattice structure of the finished open-cell foamed flow field. Once the nickel has cooled, the polystyrene plastic may be blown out of the foam with hot carbon dioxide gas or air leaving a three-dimensional nickel open-cell foamed flow field structure having substantially five-sided geometrically-shaped orifices. The nickel foamed flow field is autocatalytically microplated with up to 15 microns of gold, iridium, copper or silver. Preferably, the flow field is microplated, with between 0.5 to 2.0 microns of gold.
FIGS. 7 and 8 are electron micrographs of a three-dimensional open-cell foamed flow field of the present invention wherein the substantially five-sided orifices are visible and have been plated with gold. The advantage obtained from utilizing a three-dimensional open cell foamed flow field in the present invention is that it enhances mass transfer within the flow fields. This is because the mass transfer rate is supplemented by the foamed flow field itself and its wicking ability, which allows the molecules to electromosaticaly move through the flow field. Another advantage associated with the foamed flow fields of the present invention is that they also facilitate the deposit of the reactants uniformly along the surface of the catalytic active layers. A further distinct advantage of the foamed flow fields over conventional serpentine arrangements is that the foamed flow fields enhance the ternary reactions of the fuel cell. The gold plating further enhances the electromosatic movement of the molecules through the flow fields by providing microridges, evident in FIGS. 7 and 8 , on the surfaces of the foamed structure's orifices. These microridges facilitate the flow of the fuel, oxidant, and water in the flow fields. The gold plating enhances mass transfer by increasing the surface area of the foam by as much as a factor of nine. Another advantage of gold plating the foamed flow field of the present invention is that the leaflet potential of the gold preserves the structure of the foamed flow fields by preventing the flow fields from undergoing electrolysis. This enhances the life of the flow fields and the fuel cell assembly itself, making the fuel cell assemblies of the present invention suitable for residential and light-commercial uses.
As shown in FIG. 5 , in internal foil assembly 64 , anode gas flow field 66 and cathode gas and liquid flow field 70 are attached to primary internal foil 68 through mechanical bonding, such as sintering, plating, pressing, rolling, drawing, or extruding. Another connection means would include laminating through electrochemical adhesives. This increases the electrical conductivity through the internal foil assembly by decreasing the air gap between the flow fields and the internal foil. Preferably, internal foil 68 is plated with gold as are the flow fields so as to create an undisturbed electrical connection between the flow fields and the internal foil. When a gold-plated nickel foam is used, an alloy of copper and silver should be used to sinter the gold plated, nickel foam to internal foil assembly 64 .
FIG. 9 is an electron micrograph of one embodiment of the internal foil assembly of one embodiment of the present invention illustrating the connection as shown in FIG. 5 between anode gas flow field 66 , cathode gas flow field 70 , and internal foil 68 , wherein all three elements have been gold plated. As can be particularly seen by the arrows in FIG. 9 , the substantially five-sided orifices of the open-cell foamed gas flow fields are not deformed by the bonding process of the present invention. FIG. 10 comparatively illustrates the deformation the gas flow field suffers if bonded to the internal foil using conventional techniques. The electrically consistent connection achieved in the present invention between the flow fields and the internal foil provides for more efficient mass transfer in the internal foil assembly of the present invention.
Shown in FIG. 11 is one embodiment of the anode side (as indicated by reference numeral 120 ) of distribution frame 10 . Fuel inlet 12 and fuel inlet 14 provide the fuel to the fuel cell housed within the cavity of distribution frame 10 necessary for the electrochemical reaction. Specifically, the fuel is fed to the anode gas flow field through fuel supply channels 18 and 16 that stretch from the interior sides or surfaces of fuel inlet 12 and fuel inlet 14 , respectively. Fuel supply channels 18 and 16 are shaped such that the supply of the fuel to the anode is preferably maintained at a constant velocity, i.e., the channels are of sufficient length, width and depth to provide fuel to the anode at a constant velocity. The velocity of the fuel entering the anode gas flow field via fuel supply channels 18 and 16 may be less than the velocity of oxidant entering the cathode gas flow field via air supply channels 25 . The number of fuel supply channels in the distribution frame stoichiometrically balances the number of air supply channels so as to achieve a 2.0 to 1.0 to 2.8 to 1.0, preferably 2.0 to 1.0 to 2.4 to 1.0, air to fuel ratio. Fuel supply channels 18 and 16 also provide an edge-on connection between the fuel supply inlets and the anode gas flow field of the fuel cell housed within the cavity of the distribution frame to allow for enhanced dispersion of the fuel through the anode gas flow field. Suitable materials of construction for distribution frame 10 include nylon-6, 6, derivatives of nylon-6, 6, polyetheretherketone (“PEEK”), ABS styrene, a polyester film such as MYLAR, textar, a polyamide such as KEVLAR or any other nonconductive thermoplastic resin. Preferably, distribution frame 10 is formed from nylon-6, 6, and, if used in a stack assembly, the end plates of the fuel cell stack assembly are preferably formed from PEEK. Nylon-6, 6 is a particularly suitable material for distribution frame 10 because it dissipates electrical energy quickly so that it will not accumulate in the fuel cell assembly. It also has good compression properties. Distribution frame 10 is preferably substantially circular.
Shown in FIG. 12 is the cathode side (as indicated by reference numeral 140 ) of distribution frame 10 . Air is a necessary reactant for the electrochemical exchange, and may be fed to fuel cell 11 via air inlet 24 in combination with air supply channels 26 . Air supply channels 26 stretch from the interior surface or side of air inlet 24 to fuel cell 11 , and are of such sufficient size and shape that they enable air to be fed to the cathode gas flow field at a constant velocity, i.e., they are of sufficient height, width and depth. The number of fuel supply channels 18 and 16 will most often exceed the number of air supply channels 26 to maintain a stoichiometric balance of the reactants. Free water is formed continuously in the cathode gas and liquid flow field as a by-product of the electrochemical reaction. As described, the open-cell foamed of the cathode gas and liquid flow field facilitates the removal of this free water from the cathode gas and liquid flow field efficiently. In an alternative embodiment of the present wherein the cathode gas flow field is corrugated, the microchannels in the cathode gas flow field enhance free water removal from the system. Air and water outlet 22 and air and water outlet channels 25 facilitate the flow of this free water from fuel cell 11 to allow for optimal water management in the fuel cell, and to avoid flooding and the resultant loss in power. In a stack assembly, this free water may be transported for use in other parts of the fuel cell unit, unit here meaning the balance of plant assembly. Air and water outlet 22 and air and water outlet channels 25 also facilitate dissipation of the heat generated by the electrochemical reactions.
FIG. 13 is a cross-section of a fuel cell stack assembly shown generally at 200 that encompasses a plurality of fuel cell assemblies. Two or more individual fuel cell assemblies can be combined to form a node. Two or more nodes can be combined to form a fuel cell stack assembly. Typically, these individual fuel cells will be interposed between end plates, which are preferably substantially circular. Stacks can be placed in series to increase voltage. Stacks can be arranged in parallel to increase amperes. In one embodiment of the present invention, 1 end plate is used for every 6 fuel cell assemblies frames to provide desirable torsional properties to the fuel cell stack assembly.
Although the present disclosure has been described in detail, it should be understood that various changes, substitutions, and alterations can be made hereto without departing from the spirit and the scope of the invention as defined by the appended claims.
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An improved proton exchange membrane fuel cell assembly and fuel cell stack assembly are provided for the economical and efficient production of electricity. The present invention comprises improved flow fields, which provide improved and more efficient mass transport of the reactants in the fuel cell and the fuel cell stack assembly. The improved flow fields comprise three-dimensional open-cell foamed metals that are preferably plated with gold. The improved reactant supply system comprises an improved distribution frame to house fuel cells wherein the reactants are directly connected to the improved flow fields.
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[0001] The present invention generally relates to the collection and removal of trash or floating debris from waterways and, more particularly, to systems designed for use in combined sewer systems or storm drain conduits to trap water borne trash for removal.
BACKGROUND OF THE INVENTION
[0002] Trash and debris floating on the surfaces of waterways or along shorelines and beaches is a highly visible form of water pollution, which is receiving attention for its adverse, polluting effect and for its unaesthetic appearance on the surfaces of lakes and other water bodies. One type of system for the collecting and removing of floating debris has consisted of arrays of disposable mesh nets installed in receiving bodies of water in the flow path of a sewer outlet, particularly in applications referred to as “Combined Sewer Overflows” or “CSOs”. Such systems are described in Vol. 2, No. 3, of Fresh Creek Technologies, Inc. “Shorelines” newsletter. Systems of this type are effective in collecting floatables or trash for removal and are shown in Fresh Creek Technologies, Inc. Netting Trashtrap™ Product Bulletin. Improvements in such devices are described in U.S. Pat. No. 5,562,819, owned by the assignee of the present application, which provides an underground, in-line apparatus for trapping and collecting debris in a sewer or storm flow conduit, a secondary trap which provides continued protection when primary collection traps are full, a system which signals when primary bags or nets are full and servicing is required, and a trapping facility in which bags or nets may be replaced without loss of trapping protection during servicing.
[0003] More specifically, the device in the patent referred to above includes an enclosure or chamber with an inlet and an outlet each adapted to be connected to a sewer, storm drain conduit or outflow. A debris removing system is disposed within the chamber between the inlet and the outlet for trapping and collecting water borne debris entering at the inlet and thereby providing for an outflow of substantially debris-free water. The enclosure includes an access opening comprising upper doors or hatches or access hatches in the enclosure sized to allow the debris removing system to be removed and replaced. The debris removing system specifically includes a perforated container having an open end facing the inlet of the chamber. The perforated container includes a netting assembly that traps and collects the trash or floating debris. The container is in the form of a netting assembly having a flexible bag-shaped mesh net attached to a frame. The netting assembly is attached to lifting structure having supports or handles for allowing the frame and net to be lifted out when the net is full of captured debris. In some applications, a bypass weir or screen is provided to normally direct flow from the chamber inlet through the open end of the net while allowing flow to bypass the net and flow to the chamber outlet when the net is full of debris.
[0004] Sensing and signaling elements are typically provided for sensing and signaling the passage of solid debris around the net when the net is full of debris and is in need of servicing. The sensing and signaling elements may include mechanical structure which permits passage of water, but is displaced by impingement of solid debris flowing around the nets. Displacement of such mechanical structure signals when the net is full of debris, for example, by actuating a visible flag above ground or by actuating an electrical switch which activates an aboveground indicator or remote indicator. The sensing and signaling may include an optical sensor for detecting the passage of debris around the netting assembly. Upon detection of debris, the optical sensor emits a signal indicating that the trap is full of debris. The signal may also activate an aboveground indicator or a remote indicator.
[0005] Multiple trap systems are employed in which the enclosure includes side-by-side trap assemblies. Such systems may be configured such that, upon filling of the first trap, the flow and debris can be diverted over a bypass weir disposed between the inlet ends of the first and second traps so that flow is thereby directed through the second trap and overflow debris is trapped and collected. Closure panels may be provided in a stationary frame structure disposed adjacent the inlet ends of the traps in either the single-trap systems or the multitrap systems to restrain debris from flowing through the chamber during servicing.
[0006] The reliability of debris removing systems depends on the strength of the mesh nets and on the manner in which the net material is fabricated into the disposable net assemblies. The resultant hydraulic forces are a function of the velocity of the flow of water through the mesh of the nets as well as on the pressure exerted on the debris trapped by the nets. There are many outfalls where extreme forces exist that are too high for standard and commonly available materials or for materials made by normal fabrication practices to last.
[0007] Furthermore, the operation of such debris removal systems results in the nets filling with floatable materials over time as one or more overflows occur. In the process, large objects such as plastic bottles and sheets of plastic wrapping materials tend to cover and blind openings of the mesh, which reduces the overall effective area of the filter and results in higher hydraulic loading on the mesh, contributing to a higher pressure drop through the system and increased loads, and excessive forces on the nets.
[0008] Accordingly, a need exists for stronger and more reliable mesh nets in the traps of floatable debris collecting systems, and particularly for net assemblies that can be easily constructed and easily replaced.
SUMMARY OF THE INVENTION
[0009] A primary objective of the present invention is to provide a stronger and more reliable mesh net for the traps of systems for collecting floatable debris than have been provided by the prior art. A further objective of the invention is to provide a reliable net assembly for such systems that can be easily constructed and easily replaced.
[0010] According to principles of the present invention, disposable mesh nets are provided for debris traps that can withstand higher level of forces than can nets of the prior art. Such nets are, according to a preferred embodiment, made with a high strength and high stretch yarn and may be provided with reinforcing tape on seams and high stress areas of the net material. The flexible, stretchable mesh material allows for an increase in the free area of the mesh as the nets expand under hydraulic loads as the nets fill. High elasticity materials are those that are elastic enough, either due to their composition or the ways in which they are knitted, to allow the nets to deform when clogged with debris and thereby expand to allow flow paths around the trapped debris to minimize pressure. Nylon that has these properties would, for example, be suitable. The knit of the mesh material yarn is selected to produce the desired aperture size and maximize the breaking strength of the finished material and ability to maintain constant aperture. The material used in the manufacturing process enables the flexible mesh to maintain a consistent percentage of free area as the nets fill and expand. The material is fabricated into the form of a bag-shaped mesh net from flat material with seams that are rolled and stitched to give a strength greater than the knitted material itself.
[0011] Further according to principles of the invention, a netting assembly is provided with structure for holding the mouth of the bag-shaped net in an open position and which can be easily and securely attached to the netting material. In the preferred embodiment, the structure includes a one-piece frame that is provided with a strap configured to hold the netting material in place on the frame. The strap fits in a recessed groove molded into the outer perimeter of a generally rectangular molded plastic frame. Rows of raised buttons integrally molded into the frame extend from the bottom of the groove such that the mesh net will be sandwiched between the strap and the buttons. The frame is sized to provide sufficient strength to counter the hydraulic forces on the net. This particular embodiment of the invention is particularly suited to resist hydraulic forces in the dirty environment wherein the netting assemblies trap floating debris from waterways, sewers or storm drain conduits, as the frame assembly requires no removable locks, pins, clamps, brackets or other devices to hold down the netting material to the frame. The structure has a minimum of parts to collect debris while permitting the netting assembly to be loosened from the system with a pair of gloved hands.
[0012] In other embodiments, the netting assemblies are provided with a two part molded plastic rectangular frame, the parts of which clamp together with the knitted mesh material around the mouth of the net clamped therebetween, thereby evenly distributing the forces around the mouth of the net and holding the mouth in an open condition. The two part frame uses hole and post members on the respective parts that snap together for easy assembly. In another alternative embodiment, a one part rectangular frame is provided to which four plates having post members clamp into hole members on the frame. These embodiments have limited projections, thereby avoiding the collection thereon of debris with structure that can easily be loosened by gloved hands.
[0013] In accordance with certain principles of the invention, the traps are provided with net assemblies having a two-stage filter mesh. The nets for such traps are constructed of an inner net and an outer net. The inner net provides a first layer of mesh having larger aperture mesh openings so that the inner net captures only the larger items of debris, allowing the smaller items to pass through to the outer net or second layer of mesh. The outer net has smaller openings that trap smaller items of debris that pass through the openings of the inner net. The openings in the inner net may, for example, be at least two or three times the dimension of the openings in the outer net, or have an area from about four to ten times the area of the openings in the outer net. The outer net may also have a greater volume than the inner net, for example, at least about one fourth larger than that of the inner net. The two stage filter produces a larger effective filtering capacity, in that the trap does not blind as quickly, holds more material and distributes the hydraulic loads between the two layers resulting in greater overall strength. Further, were the first or inner net to fail, the second or outer net retains the ability to trap additional debris.
[0014] These and other objectives and advantages of the present invention will be more readily apparent from the following detailed description of the preferred embodiments of the invention, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] [0015]FIG. 1 is a perspective view showing the common features of a debris trapping system of the prior art for the removal of trash or floatables from flowing water.
[0016] [0016]FIG. 1A is an underground in-line version of the prior art system of FIG. 1.
[0017] [0017]FIG. 1B is a floating version of the prior art system of FIG. 1.
[0018] [0018]FIG. 1C is an end-of-pipe version of the prior art system of FIG. 1.
[0019] [0019]FIG. 2 is a perspective view of the net assembly of a trap according to certain principles of the invention.
[0020] [0020]FIG. 2A is a cross-sectional view along line 2 A- 2 A of FIG. 2.
[0021] [0021]FIG. 2B is a cross-sectional view along line 2 B- 2 B of FIG. 2.
[0022] [0022]FIG. 3 is a perspective view of the net of a trap utilizing a net frame construction alternative to that of FIG. 2.
[0023] [0023]FIG. 3A is a cross-sectional view along line 3 A- 3 A of FIG. 3.
[0024] [0024]FIG. 3B is a cross-sectional view along line 3 B- 3 B of FIG. 3.
[0025] [0025]FIG. 3C is a cross-sectional of an alternative to FIG. 3B.
[0026] FIGS. 4 A- 4 B are cross-sectional views illustrating double net construction according to certain embodiments of the present invention.
[0027] [0027]FIG. 5 is a perspective view of the net assembly of a trap according to an alternative embodiment of the invention.
[0028] [0028]FIG. 5A is a cross-sectional view along line 5 A- 5 A of FIG. 5.
[0029] [0029]FIG. 5B is a cross-sectional view along line 5 B- 5 B of FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0030] [0030]FIG. 1 illustrates the basic components of one system 10 of the prior art described in the background of the invention above. The system 10 includes one or more traps 12 , illustrated as two in number, separately designated as traps 12 a and 12 b . The traps 12 a , 12 b are located within a flow constraining housing or enclosure 11 between inlet 13 and outlet 14 thereof. The inlet 13 and the outlet 14 are each respectively connected in a known manner to conduits 15 and 16 , which may be storm drain or combined sewer conduits or other structures or the terrain of the site. The traps 12 a , 12 b each include a netting assembly 19 formed of a bag-shaped mesh net 17 that is attached to a lifting basket 18 . Each of the netting assemblies 19 captures and holds floatable velocity borne debris 20 entering enclosure 11 through inlet 13 . The arrows 25 indicate the direction of water flow.
[0031] Perforations or openings in nets 17 may vary in size depending on the intended use, with sizes generally in the range of from about 0.1″ to about 2″. Nets 17 are open on the upstream facing end 17 a thereof, toward inlet 13 of enclosure 11 . Upper support members (not shown in FIG. 1) are attached to lifting baskets 18 for allowing the netting assemblies 19 of traps 12 a , 12 b to be lifted out of enclosure 11 for periodic removal of captured debris. The netting assemblies 19 are configured such that the nets 17 provide a large filter area for the size of the mouth, thereby minimizing head loss. For example, 80 square feet of net 17 may be provided for a netting assembly mouth area of 6½ square feet, resulting in a pressure drop across a net 17 of three or four pounds.
[0032] A bypass weir (not shown in FIG. 1) or screen is typically located upstream of traps 12 and on one side of inlet 13 to permit continued flow in the event that the nets 17 of traps 12 a , 12 b are filled to capacity with debris. To signal that nets 17 of the netting assemblies 19 of traps 12 a , 12 b are in need of replacement or emptying, sensing and signaling mechanisms may be provided. The multiple trap system 10 can be configured to provide continuous and uninterrupted capture of debris through second trap 12 b after the netting assembly of first trap 12 a has been filled and during the process of removing and replacing it. While servicing is being performed, movable panels can be positioned in front of each respective trap 12 a or 12 b being serviced, as necessary, prior to its removal from enclosure 11 . In this way, the system 10 is protected against passage of floatable debris during net removal and replacement.
[0033] FIGS. 1 A- 1 C illustrate the basic system 10 of the prior art in three environments. These arrangements are generally described in a publication of the United States Environmental Protection Agency, Office of Water, No. EPA 832 -F-99-037, September, 1999, hereby expressly incorporated by reference herein.
[0034] In particular, in FIG. 1A, an in-line system 10 a is illustrated in which the two traps 12 a , 12 b are contained in an enclosure in the form of an underground or subterranean vault 11 a . The vault 11 a includes its inlet 13 a and its outlet 14 a respectively connected to conduits in the form of buried pipes 15 a , 16 a , for example, of a storm drain. The in-line traps 12 a , 12 b each include a netting assembly 19 with a mesh net 17 installed in and held in place by a respective lifting basket 18 . A lifting bridle (not shown) is attached to upper support members 21 of the lifting basket 18 for allowing the netting assemblies 19 of traps 12 a and 12 b to be lifted out of vault 11 a through doors 22 a for periodic removal of captured debris. A bypass screen 23 a is located above the traps 12 a , 12 b to allow flow to divert from the inlet 13 a to permit continued flow in the event that nets 17 of the traps 12 a , 12 b are both filled to capacity with debris.
[0035] In FIG. 1B, a floating system 10 b is illustrated that is configured to float in a body of water in front of a stream, pipe or other water source from which enters into the body of water a flow of water containing trash or floatables to be removed by the system. The direction of water flow into and through the system 10 b is also indicated by arrows 19 . The floating system 10 b also includes two traps 12 a , 12 b , shown in a floating hull 11 b that is provided with closed cell foam panels 23 and pontoons to float the hull at the surface 28 of the body of water. The traps 12 a , 12 b also each include a mesh net 17 held in place within a lifting support 18 a . Because the system 10 b is floating and the traps 12 a , 12 b are immersed in water, a less extensive support frame 18 a is substituted for the lifting basket 18 of system 10 a , described above.
[0036] In the system 10 b , the hull 11 b has its inlet 13 b extending above and below the surface 28 of the water so that trash or floatables at and immediately below the surface enter through it into the interior of the hull 11 b . The hull 11 b has its outlet 14 b below the water surface 28 on the back of the hull 1 b . The inlet conduit 15 is formed of a set of curtains 15 b which hang from below the inlet 13 b and from floats 24 extending respectively between the hull 11 b on both sides of the inlet 13 b to the shore on the opposite sides of the flowing source, connected to buried concrete conduits (not shown) of a storm drain, for example. The curtains 15 b may extend from the water surface 28 to the bottom 29 of the water body and channel water from the source into the inlet 13 b . The traps 12 a , 12 b are supported in the hull 11 b in a manner similar to the way they are supported in the vault 11 a described above. They can be lifted out of hull 11 b through grate doors 22 b for periodic removal of captured debris from the nets 17 thereof.
[0037] In FIG. 1C, an end-of-pipe system 10 c is illustrated in which the two traps 12 a , 12 b are shown in an enclosure in the form of a surface mounted three-sided concrete headwall and knee wall enclosed cavity 11 c having an open end that defines its outlet 14 c . The cavity 11 c has its inlet 13 c connected to a pipe 15 c draining into the cavity 11 c . The traps 12 a , 12 b each include a net assembly 19 having a mesh net 17 . A fiberglass drain grating 16 c is provided beneath the netting assemblies 19 to allow flow to exit each net 17 through its bottom to the outlet 14 c of the enclosure 11 c . The net 17 of each netting assembly is attached to a lifting structure (not shown), which may be similar to the lifting basket 18 described in FIG. 1A above, or in the form of lifting frame 18 a described in FIG. 1B above where the traps 12 a , 12 b are submerged. Door grates 22 c are provided above the traps 12 a , 12 b to permit them to be raised for periodic removal of captured debris. A bypass weir 23 c may be located above the traps 12 a , 12 b to allow flow to divert from the inlet 13 to permit continued flow in the event that traps 12 a , 12 b are both filled to capacity with debris.
[0038] In FIGS. 2, 2A and 2 B are illustrated netting assemblies for the traps 12 for use in systems 10 of the various types illustrated in FIGS. 1 A- 1 C described above. According to certain aspects of the invention, the netting assemblies 19 are constructed with a mesh net 17 connected to a frame assembly 30 . The frame assembly 30 includes a rectangular frame body having a pair of horizontal top and bottom members 31 and 32 , respectively, and a pair of side members 33 . The top member 31 is wider than the bottom member 32 , and the side members 33 are tapered from the wider top member toward the narrower bottom member 32 , as illustrated in FIG. 2B, for easy installation and removal from the lifting basket 18 or support frame 18 a . The side members 33 are also inwardly tapered in the downstream direction, as illustrated in FIG. 2A, to lock into the supporting rails as the flow goes through the nets 17 . Flow direction is indicated by the arrows 25 .
[0039] Each of the members 31 - 33 has a rim 34 on the upstream side thereof and a recessed step 35 on the downstream side thereof. A pattern of holes 36 is formed in the steps 35 of each of the members 31 - 33 . Each of the members 31 - 33 has associated therewith a plate 37 having a plurality of projections in the form of posts 38 arranged in a pattern that corresponds to the pattern of the holes 36 in the respectively associated member 31 - 33 of the frame 30 so that the plates 37 can be connected to the members 31 - 33 by snap fitting the posts 38 into the holes 36 . The plates 37 are so connected with the edge of the mouth of the net 17 between the plate 37 and the respective member 31 - 33 and the posts 38 extending through holes in the mesh of the net 17 , thereby locking the mouth of the net 17 to the frame 30 . When so connected, the plates 37 set into the steps 35 so that the tops thereof are flush with the lip 34 of the members 31 - 33 . When the net 17 is attached to the frame 30 , the net extends around the outside of the members 31 - 33 with the mouth of the net wrapping around the upstream side of the frame 30 to the inside of the frame 30 and between the plates 37 and the members 31 - 33 .
[0040] The frame 30 may be made of wood and the plates 37 made of metal, but other materials may be used. In one preferred embodiment, the frame 30 is formed of an integral piece of molded plastic material. The plates 37 may also be formed of molded plastic. The frame 30 securely attaches to the nets 17 by being formed of elements that clamp together with the mesh material of the nets 17 between them, with one of the elements having posts or projections thereon against which the other member bears so that the projections serve as hooks that trap the net between the elements while the other element prevents the net from slipping off the projections.
[0041] An alternative frame structure 18 is illustrated in FIGS. 3, 3A, 3 B and 3 C, in which mesh net 17 is shown connected to a frame assembly 40 . The frame assembly 40 is a two part rectangular frame that includes an inner frame portion 40 a having an array of holes 46 on the upstream facing side thereof and an outer frame portion 40 b having a matching array of posts on the downstream facing side thereof. The two portions 40 a , 40 b of the frame snap together and clamp the mouth of the net 17 therebetween. The two parts of the frame 40 are preferably formed of an integral piece of molded plastic, but other materials may be used.
[0042] The frame 40 has a pair of horizontal top and bottom members 41 and 42 and a pair of side members 43 . The side members are tapered inwardly in the downstream direction and fit in correspondingly tapered vertical channels 44 in vertical rails 45 that are part of the lifting basket 18 or support frame 18 a . Further, the top member 41 is thicker in the flow direction (that is, upstream to downstream) than is the bottom member 42 ; and the side members 43 are correspondingly tapered in the downward direction to fit into the channels 44 , which are similarly tapered, as illustrated in FIG. 3A. As a result of the tapers, the frame 40 of the netting assemblies 19 fit firmly in the channels 44 of the rails 45 when in position, but can be loosened by impact and removed with a minimum of sliding friction. FIG. 3B shows the net 17 wrapped around the outside of the frame 40 with the mouth of the net 17 wrapping around the front of the frame 40 and extending between the portions 40 a , 40 b thereof from the inside. Alternatively, FIG. 3C shows the net 17 wrapped around the inside of the frame 40 with the mouth of the net 17 wrapping around the front of the frame 40 and extending between the portions 40 a , 40 b thereof from the outside.
[0043] As a result of the tapers described above, the greater the forces on the traps, the more tightly the mesh nets 17 are gripped and the less likely are the nets to pull out or tear around the posts.
[0044] [0044]FIG. 4A illustrates a two layered net 17 that includes an inner net 17 a of a course mesh having holes mounted to frame structure 18 c so as to extend through the inside of the frame and with an outer net 17 b of a fine mesh mounted to frame structure 18 c so as to extend around the outside of the frame and thereby enclosing the inner net. The holes in the inner net 17 a may, for example, be about 1-2 inches in size with the holes in the outer net 17 b being of about {fraction ( 1 / 2 )} inches in size. The holes of the inner net 17 a should be at least two to three times larger on a side than those of the outer net, with a cross sectional area of at least about four times the area of the holes of the outer net. As a result, large pieces of debris 48 such as plastic bottles, cans, plastic bags, styrofoam cups, etc. only are trapped by the inner net 17 a while smaller pieces of debris 49 pass through the larger holes of the inner net 17 a and are trapped by the outer net 17 b.
[0045] [0045]FIGS. 5, 5A and 5 B illustrate netting assemblies for the traps 12 that are alternative embodiments of the assemblies of FIGS. 2 - 2 B and FIGS. 3 - 3 C described above. In FIGS. 5 - 5 B, the traps 12 are each constructed with mesh net 17 connected to a frame assembly 50 . The frame assembly 50 includes a rectangular frame body. As with the embodiments above, the frame 50 is preferably formed of an integral piece of molded plastic, but other materials are suitable. The body of frame 50 has a pair of horizontal top and bottom members 51 and 52 , respectively, and a pair of side members 53 , with the top member 51 wider than the bottom member 52 and the side members 53 tapered from top to bottom as was illustrated in the embodiment of FIG. 2B. The side members 53 are also inwardly tapered in the downstream direction, as illustrated in FIG. 5A. Each of the members 51 - 53 has an outside surface 54 having a groove 55 extending around the frame 50 . On the bottom surface of the groove 55 is preferably a plurality of projections or posts 56 to help grasp the netting material, particularly where the frame is formed of plastic or other low friction material. A clamping element in the form of a tension band 57 lies in the groove 55 in contact with the tips of the projections 56 . The tension band may be of a natural fiber, metal or plastic. Plastic is particularly suitable for the band 57 . The net 17 extends between the band 57 and the frame members 51 - 53 , so that the mouth of the net 17 is locked to the frame 50 . When the frame 50 is inserted into the rails of the system, the tapered frame is forced against the frame by the forces produced by the flowing water on the net 17 to further clamp the net 17 between the frame 50 and the rail.
[0046] Other applications of the invention can be made. Those skilled in the art will appreciate that the applications of the present invention herein are varied, and that the invention is described in preferred embodiments. Accordingly, additions and modifications can be made without departing from the principles of the invention. Accordingly, the following is claimed:
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A disposable net assembly is provided for a trap for collecting floatable debris in a waterway or combined sewer system. The net assembly includes a knitted bag-shaped mesh net having a frame surrounding the mouth of the net with the net secured around its rim to the frame. The net may be formed of an inner layer and an outer layer of mesh with the openings of the inner layer being substantially larger than the openings of the outer layer. The frame may be formed of a plastic molded material having side members tapered in the vertical direction to facilitate the changing of the netting assemblies and tapered in the downstream direction to lock into place under the force of the flow. Several embodiments of the frame members have projections thereon which cooperate with a clamping element to hold the net to the frame. Some embodiments of the members have parts that lock together with a post and hole construction while others employ a tension band to clamp the net to the projections on the frame. The net is preferably secured around its rim to the frame, with the mouth of the net extending around the outside and upstream side of the frame and over the surface having the projections. The net is preferably formed of a high strength and high stretch yarn, with rolled sewn seams and having reinforcing on the seams and on high stress areas of the net.
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FIELD OF THE INVENTION
The present invention relates to a base-mounted electromagnetic valve, wherein an electromagnetic valve for changing over passages of a working fluid is mounted on a base member such as a manifold with pipe ports and power supply sockets for supplying power and a subplate.
PRIOR ART
Base-mounted electromagnetic valves of this sort are, as disclosed in Japanese Patent Laid-Open No. 2603160, generally provided with power supply sockets on the base member side for connection to a power source, and pin-shaped power receiving terminals for connection to a solenoid is placed on the electromagnetic valve side such that the power receiving terminal is connected to the power supply socket when the electromagnetic valve is mounted on the base member.
In the case of such a base-mounted electromagnetic valve, when mounting an electromagnetic valve on a base member, for the sake of a work procedure and an inspection procedure, it is desirable to have a construction wherein not only a finished electromagnetic valve can be mounted but also a semifinished electromagnetic valve without a pilot valve is mounted first and the pilot valve can be installed afterward. Also, in the case when maintenance checks of an electromagnetic valve in use are made, it is desirable to have a construction such that a pilot valve alone is removable while the electromagnetic valve remains mounted on the base member.
However, since many of conventional base-mounted electromagnetic valves are generally provided with power receiving terminals and solenoids fixedly connected to each other, it has been difficult to mount pilot valves afterward during assembly or to replace the pilot valves alone when maintenance services are made.
Also, there have been quite a few base-mounted electromagnetic valves whose externally exposed portions of electric conductors might contact tools, hands and so on.
SUMMARY OF THE INVENTION
It is therefore a technological object of the present invention to provide a base-mounted electromagnetic valve efficiently constructed so as to permit a pilot valve to be mounted, removed and so on easily simply by incorporating a simple power supply mechanism between a base member and an electromagnetic valve, and to facilitate assembly, inspection processes, maintenance services and so on.
It is another technological object of the present invention to permit the above-described base-mounted electromagnetic valve to be electrically connected easily and safely without being mistakenly connected when mounting or removing the pilot valve.
In accordance with the present invention, the above-stated objectives are achieved by the provision of a base-mounted electromagnetic valve comprising a base member having pipe ports and power supply sockets for supplying power, and an electromagnetic valve mounted on the base member.
The above base member has the power supply sockets connected to a power source and received in a recess formed on an electromagnetic valve mounting surface.
On the other hand, the above electromagnetic valve has a main valve portion having a valve member for changing over working fluids, a pilot valve portion having an electromagnetic pilot valve operating the above valve member, and an intermediate block disposed between the main valve portion and the pilot valve portion. The above pilot valve portion has a circuit board incorporating a protective circuit electrically connected to a solenoid of the pilot valve, and a plurality of pin-shaped lead-in terminals with one end connected to the protective circuit of the circuit board and the other end extending toward the above intermediate block. Further, the above intermediate block has a recessed portion formed on a joint surface with the pilot valve, and a cylindrical fit-in portion which is formed on a joint surface with the base member and fits in the above recessed portion. Also, the intermediate block is provided with a relay connector which detachably connects the lead-in terminals of the above pilot valve with the power supply sockets of the base member.
Since the base-mounted electromagnetic valve of the present invention has a construction such that the power supply sockets of the base member and the lead-in terminals of the pilot valve portion are detachably connected by way of the relay connector provided in the intermediate block, not only can a finished electromagnetic valve be mounted on the base member during assembly of the base-mounted electromagnetic valve, but also a semifinished electromagnetic valve without a pilot valve is mounted first, and then the pilot valve can be installed afterward. Also, the pilot valve alone can be detached or attached during maintenance, which considerably facilitates assembly and inspection processes or maintenance and other services of the base member.
Moreover, since all that is required is to incorporate the relay connector in the intermediate block, the power supply mechanism can be a quite simple one.
According to a specific embodiment of the present invention, the above relay connector has a plurality of relay sockets connectable to each of the lead-in terminals of the pilot valve portion, a relay board with the relay sockets mounted thereon, a plurality of pin-shaped relay terminals with one end being attached to the relay board to be electrically connected to each of the relay sockets and the other end extending in the fit-in portion, and a terminal holder holding the relay terminals and the relay board.
It is desirable that the above terminal holder is removably mounted in a recessed portion of the intermediate block by resilient hooks provided on the side surfaces.
According to another specific embodiment of the present invention, pin-shaped solenoid terminals extending from a solenoid and the above lead-in terminals are respectively provided such that they protrude from the other side of the mounting surface of the above pilot valve to the intermediate block. In addition, a protective wall to surround these terminals for safety is formed, and the above circuit board is removably attached to the above solenoid terminals and the lead-in terminals in such a manner that each of the terminals is fitted in a plurality of board sockets on the circuit board within the above protective wall.
Also, in the present invention, the pilot valve portion has a cover entirely covering the pilot valve and the circuit board, the circuit board is mounted inside the cover, and the respectively board sockets are connected to solenoid terminals and lead-in terminals by fastening the cover to the intermediate block.
With the above-described construction, after mounting the pilot valve on the intermediate block, the pilot valve portion can be easily and promptly installed simply by mounting a cover. Also, an operation can be carried out safely, as possibilities of wrongly connections and contacts to externally exposed conductor portions are precluded.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view of a base-mounted electromagnetic valve according to an embodiment of the present invention;
FIG. 2 is a separately shown enlarged view of a principal part of FIG. 1;
FIG. 3 is an exploded view in perspective of a relay connector; and
FIG. 4 is a perspective view illustrating another form of the electromagnetic valve.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a preferred embodiment of a base-mounted electromagnetic valve according to the present invention. The base-mounted electromagnetic valve illustrated therein comprises a base member 1 such as a manifold or a subplate, and an electromagnetic valve 2 mounted on the base member 1.
A valve mounting surface 11 on which the electromagnetic valve 2 is mounted is formed on a top surface of the base member 1, and in the base member 1 are formed respectively a supply through hole 12 for a working fluid opened in the valve mounting surface 11, two output through holes 13a, 13b, and two discharge through holes 14a, 14b . The above supply through hole 12 and two discharge through holes 14a, 14b are individually in communication with a supply port P and two exhaust ports EA, EB opened on the side surface seen in the front of the drawing, and two output through holes 13a, 13b are individually in communication with two output ports A, B opened in a side surface of the opposite side of the valve in the drawing.
In the drawing, PE is a pilot exhaust port opened in the front end face of the base member 1, and X is an external pilot port introducing an external pilot fluid.
At a rear end portion of the base member 1, a power supply portion 16 for supplying power to the electromagnetic valve 2 is formed. As seen in FIG. 2, the power supply portion 16 has a hollow terminal box 18 housing a plurality of connecting terminals 19 for connection to a feeder 17 from a power source, a feeder introduction port 20 for introducing the feeder 17 into the terminal box 18, a recess 21 formed on the valve mounting surface 11, a plurality of power supply sockets 22 disposed in the recess 21 while being held by a socket holder 23, and a lead 24 and a connector 25 connecting the power supply sockets 22 to the respective connecting terminals 19. The numeral 26 denotes a sealing member.
On the other hand, the above electromagnetic valve 2 is a single pilot type 5-port valve and is provided with a main valve portion 3 and a pilot valve portion 5. The main valve portion 3 has a parallelepiped valve body 30 extending longitudinally and having a rectangular section. Into a valve hole 31 formed in the valve body 30 is inserted a spool type valve member 32 for changing over passages of a working fluid from one to another. Also, the pilot valve portion 5 is provided with an electromagnetic pilot valve 35 for operating the valve member 32, and the main valve portion 3 and the pilot valve portion 5 are coupled together separably by means of an intermediate block 4, -which incorporates an amplifier valve 36 for amplifying a pilot fluid.
In the valve body 30 of the main valve portion 3 are provided a supply through hole 38 for individual communication with each through hole on the valve mounting surface 11 of the base member 1, two output through holes 39a, 39b, and two discharge through holes 40a, 40b . Each of these through holes is in communication with the valve hole 31.
At both ends of the valve member 32 are formed a large-diameter pressure chamber 42 for allowing the pilot fluid to operate on the valve member 32 directly, and a small-diameter pressure chamber 43 for allowing the pilot fluid to operate by way of a piston 44. The large-diameter pressure chamber 42 is in communication with the supply through hole 38 via pilot passages 46a, 46b, 46c, 46d and 46e by way of a passage change-over means 47, a manual operation mechanism 48, the amplifier valve 36 and the pilot valve 35. On the other hand, the small-diameter pressure chamber 43 is in constant communication with the supply through hole 38 via pilot passages 46a, 46f and 46g by way of the passage change-over means 47. As a result, like a conventional single pilot valve, the pilot valve 35 is turned on and off to supply and discharge the pilot fluid to and from the large-diameter pressure chamber 42, or a manual operation mechanism 48 is manipulated to bring the large-diameter pressure chamber 42 directly in communication with the supply through hole 38 or block the above communication, to operate the valve member 32.
In the drawing, 49a and 49b are cushioning members to absorb impacting force at stroke ends of the valve member 32.
The above-described passage change-over means 47 is for the changing of the electromagnetic valves 2 between an internal pilot type and an external pilot type. The valve shown in the drawing is the internal pilot type leading the pilot fluid into the pilot valve 35 through the pilot passage 46a branched off from the supply through hole 38, and by mounting the passage change-over means 47 in such a way that its left and right shown in the drawing are reversed, the pilot passage 46a is blocked and the pilot passages 46b, 46f can be connected to an external pilot passage 46h, which is in communication with the external pilot port X.
The above intermediate block 4 has a recessed portion 50 which is formed on a joint surface with the pilot valve 35, and a cylindrical fit-in portion 51 for fitting in the recess 21 is formed on the joint surface with the base member 1. Also in the recessed portion 50, there is a relay connector 53 mounted for separably connecting a plurality of pin-shaped lead-in terminals 52 formed in the pilot valve portion 5 to the power supply socket 22 on the base member 1.
The above relay connector 53 is constructed as shown in FIG. 3. This relay connector 53 is provided with two sets of members for electric connection so as to be used even when the electromagnetic valve 2 is switched to a double pilot type. Namely, the relay connector 53 comprises the terminal holder 55 formed of insulating material such as a synthetic resin, a plurality of pin-shaped relay terminals 57 attached sot that they are pressed into mounting holes of the terminal holder 55 with one end protruding toward the side of the base member 1 and the other end formed in L shape to face the side of the pilot valve 35, a plurality of relay sockets 58 into which end portions of the respective lead-in terminals 52 are fitted to be connected, a relay board 59 provided with the relay sockets 58, and socket covers 60 being resiliently attached to the relay board 59 by means of pawls 60a and covering the relay sockets 58. Further, an end portion of the relay terminal 57 is inserted into a contact hole 59a of the relay board 59 and soldered, whereby each of the relay terminals 57 and the relay sockets 58 are connected to each other, and the relay board 59 is mounted to the terminal holder 55.
The terminal holder 55 is provided with resilient hooks 55a on both side faces, and is detachably mounted to the intermediate block 4 by resiliently engaging the hooks 55a to the intermediate block 4 in the recessed portion 50. However, the terminal holder 55 can be mounted to the intermediate block 4 by means of screws instead of the hooks 55a.
The terminal holder 55 may be provided with a set of electrically connecting members alone.
Furthermore, the pilot valve portion 5 has the pilot valve 35 mounted to the intermediate block 4, a circuit board 64 mounted on a side opposite to a mounting surface of the pilot valve 35 to the intermediate block 4, and a cover 65 entirely covering the pilot valve 35 and the circuit board 64.
The circuit board 64 incorporates a protective circuit having a diode 66 for prevention of a counter electromotive force and other purposes, and a light-emitting diode 67 for displaying an electric flow state by wiring printed on the surface thereof. Also, there are provided a plurality of board sockets 68 electrically connected to the protective circuit, and the circuit board 64 is mounted inside the cover 65. The portion of the cover 65 that faces the light-emitting diode 67 is a transparent display window 65a.
On the other hand, provided on a mounting surface of the pilot valve 35 to the circuit board 64 are a pin-shaped solenoid terminal 70 extending from a solenoid and the lead-in terminal 52 passing through the pilot valve 35, and a protective wall 71 is further provided so as to completely or partially surround these terminals 52, 70 respectively. Moreover, when the cover 65 is mounted after installation of the pilot valve 35 to the intermediate block 4, each of the board sockets 68 respectively fits the solenoid terminal 70 and the lead-in terminal 52 within the protective wall 71, allowing the circuit board 64 to be automatically mounted to the pilot valve 35. At this time, as seen in FIG. 2, the cover 65 and the terminal holder 55 are positioned in such a manner that the projections 65b formed on the cover 65 fit in the holes 55b of the terminal holder 55.
In a base-mounted electromagnetic valve having above construction, the power supply socket 22 of the base member 1 and the lead-in terminal 52 of the pilot valve portion 5 are separably connected by way of the relay connector 53 provided in the intermediate block 4 so that not only can a finished electromagnetic valve 2 be mounted on the base member 1 during assembly of the base-mounted electromagnetic valve but also a semifinished electromagnetic valve 2 without the pilot valve 35 can be mounted first, followed by later installation of the pilot valve 35. Also, the pilot valve 35 and the terminal holder 55 can be easily detached or attached by removing the cover 65 during maintenance. Therefore, above construction is advantageous not only for assembly and inspection processes of the base-mounted electromagnetic valve but also for maintenance services and so on.
Moreover, since the above effect is achieved simply by incorporating the relay connector 53 into the intermediate b lock 4, a power supply mechanism can be a quite simple one.
Although the above-described embodiment is of a single pilot type electromagnetic valve 2, the electromagnetic valve may be a double pilot type electromagnetic valve 2A as shown in FIG. 4. In this case, the pilot valve portion 5 is provided with two pilot valves 35, 35. Though these pilot valves 35, 35 may be formed separately and placed side by side on the intermediate block 4, the two pilot valves 35, 35 may be integrated by being sealed into a synthetic resin. Also, it is needless to say that, in the case of a double pilot type, two sets of terminals, sockets, manual operation mechanisms and the like are provided respectively to correspond with the two pilot valves.
Moreover, the electromagnetic valves applicable are not limited to 5-port valves, and other electromagnetic valves having a different number of ports such as 3-port valves, 4-port valves and 2-port valves may be used.
As shown in the above construction according to the invention, the power supply sockets of the base member and the lead-in terminals of the pilot valve portion are separably connected by way of the relay connector provided in the intermediate block so that it is possible not only to mount a finished electromagnetic valve on the base member during assembly of a base-mounted electromagnetic valve, but also to mount a semifinished electromagnetic valve without a pilot valve first and to install the pilot valve afterward. Further, it is also possible to detach or attach the pilot valve alone when maintenance is made, which is considerably advantageous for assembly and inspection procedures, maintenance services and the like of the base member.
Moreover, since incorporating the relay connector in the intermediate block is all that is needed, construction of a power supply mechanism can be made quite simple.
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To obtain a base-mounted electromagnetic valve, wherein removal and mounting of a pilot valve of the electromagnetic valve is facilitated to allow its assembly, maintenance and the like to be carried out easily simply by incorporating a simple power supply mechanism between a base member and the electromagnetic valve. In order to achieve this object, a recessed portion disposed on a joint surface with a pilot valve and a fit-in portion capable of fitting into a recess wherein power supply sockets of the base member are formed are provided in an intermediate block which separably connects a main valve portion of the electromagnetic valve with a pilot valve portion, and a relay connector which separably connects lead-in terminals of said pilot valve portion with the power supply sockets of the base member is provided within said recessed portion.
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BACKGROUND OF THE INVENTION
The invention relates to a semiconductor device comprising a semiconductor body of silicon with a p-type surface region adjoining a surface and provided with an n-type channel field effect transistor with insulated gate and with n-type source and drain zones provided in the surface region and mutually separated by an interposed channel region also adjoining the surface, while the surface region is provided with a buried p-type doped zone which extends below the channel region at a small distance from the surface and which has a higher doping concentration than the channel region. Such a device is known from U.S. Pat. No. 5,166,765.
The mobility of the charge carriers in the channel, often indicated with the symbol μ and expressed in cm 2 /V.s, is an important parameter in MOS transistors with channel dimensions in the deep sub-micron region (for example, 0.1 micron), inter alia in view of the capacity of the transistor to conduct current. The mobility is strongly dependent on the value of the electric field in the channel, at least on the component of the field transverse to the surface. In general, the mobility decreases with an increasing field strength. The doping concentration in the channel should accordingly be very low in order to obtain a high mobility, for example of the order of 10 15 atoms per cm 3 (intrinsic silicon). Such a low doping level, however, is not possible because punch-through to the source occurs at very low drain voltages already with this doping. In addition, low channel doping levels in combination with very small dimensions (for example, a channel surface area of 0.1 μm×0.1μm) may lead to major fluctuations in the threshold voltage, which may be particularly unfavorable at lower supply voltages owing to fluctuations in the doping level. These problems are solved in principle in a transistor as described in the cited U.S. Pat. No. 5,166,765. In this known transistor, the channel region comprises an intrinsic surface region which adjoins the surface, has a thickness of a few tens of nanometers, and is situated above and adjoining a thin p-type layer having a high concentration of boron atoms, for example of the order of 10 18 per cm 3 . A transistor constructed in this way has a high mobility of charge carriers, a high punch-through voltage, and a good threshold voltage. The extremely small dimensions, however, render it difficult to manufacture such a transistor in a reliable and reproducible manner. Moreover, a separate implantation of As ions is required in the channel region of the transistor so as to compensate for the B atoms present and make the silicon in the channel region intrinsic. Such an As implantation in the channel, however, is disadvantageous for the mobility of the charge carriers and for the process control, for example as regards the threshold voltage V T .
SUMMARY OF THE INVENTION
The invention has for its object to provide a device of the kind described in the opening paragraph which can be manufactured in a reliable and reproducible manner. The invention also has for its object to provide such a device in which a separate As implantation in the - intrinsic - channel region is unnecessary, so that the mobility in the channel is not adversely affected by impurities.
According to the invention, a semiconductor device of the kind described in the opening paragraph is characterized in that the surface region is in addition provided with a buried Si 1−x Ge x layer (called SiGe layer hereinafter), x representing the molar fraction of Ge, extending below the channel region and forming a diffusion barrier between the comparatively weakly doped channel region adjoining the surface and the comparatively strongly doped buried p-type zone.
The invention is based inter alia on the recognition that the diffusion of boron atoms to the surface may be fairly strong owing to the small depth of the buried p-type zone, in particular because of the growing of the gate oxide during which empty places arise in the crystal lattice which promote the diffusion of boron atoms. The invention is further based on the recognition that this diffusion may be decelerated by a SiGe layer whose thickness is so small that the lattice distances, at least in a direction parallel to the surface, are equal or at least substantially equal to the lattice constants in the silicon crystal. This renders it possible to form the channel region through epitaxy of intrinsic silicon on the SiGe layer. The gate oxide may be formed in a subsequent step, during which the diffusion of boron atoms is decelerated by the SiGe layer.
It is noted that, wherever reference is made to an SiGe layer below, this should be understood to include all layers in which Si is replaced by Ge in a number of lattice points of the crystal. Besides Ge, the layer may comprise other substances, for example C, as long as the layer is electrically conducting, diffusion-inhibiting, and monocrystalline, so that an intrinsic silicon layer can be epitaxially deposited on the layer. The SiGe layer may be formed through implantation of Ge into the silicon crystal. This, however, leads to major damage in the crystal, in particular when the Ge content becomes greater, for example when x is approximately 0.3. A major preferred embodiment of a semiconductor device according to the invention, which has the advantage that the composition of the SiGe layer may be chosen within wide limits, is characterized in that the SiGe layer and the channel region adjoining the surface are formed by epitaxial layers.
Conventional separation techniques such as thick field oxide may be used for the lateral boundaries of the active regions in the semiconductor body. Since a thermal treatment of long duration is less desirable after the application of the SiGe layer and the intrinsic layer, the field oxide is preferably provided first, after which the SiGe layer and the intrinsic layer are deposited in the active regions, for example by selective epitaxy. An embodiment in which the provision of the lateral boundaries does not require a high-temperature step of long duration and in which the lateral boundaries can be provided after the SiGe layer has been deposited, is characterized in that the transistor is laterally bounded in the semiconductor body by grooves which may or may not be filled up with a filler material and which extend from the surface into the semiconductor body to a depth which is greater than the depth of the source and drain zones.
The invention may be used to advantage in integrated circuits with exclusively n-channel field effect transistors. An important class of integrated circuits comprises complementary field effect transistors (CMOS) in which p-channel transistors are present as well as n-channel transistors. A semiconductor device incorporating a further aspect of the invention is characterized in that at the area of an n-type surface region adjoining the surface the semiconductor body is provided with a p-channel field effect transistor with insulated gate and with p-type source and drain zones which are provided in the n-type surface region and are mutually separated by an interposed channel region, the n-type surface region being provided with a buried n-type zone below the channel region, which zone is doped with As or Sb with a doping concentration higher than that of the channel region adjoining the surface and that of a buried Si 1−x Ge x layer. This aspect of the invention is based inter alia on the recognition that it is desirable also for the p-channel transistor that a strongly doped n-type layer should be provided at a depth of a few tens of nanometers from the surface for reasons analogous to those for the n-channel transistor. SiGe, however, does not form a diffusion barrier for n-type impurities. Accordingly, the channel region would be strongly doped by the buried layer when P is used, which has a diffusion constant comparable to that of B. The use of the n-type dopant As, or possibly Sb, renders it possible to choose the process conditions in a simple manner such that the diffusion of the As atoms or the Sb atoms stops at the boundary between the SiGe layer and the intrinsic channel region situated above it, so that the channel region nevertheless remains practically intrinsic at the surface.
BRIEF DESCRIPTION OF THE DRAWING
These and other aspects of the invention will be explained in more detail with reference to an embodiment. In the drawing:
FIG. 1 is a cross-section of a semiconductor device according to the invention;
FIGS. 2 to 6 are cross-sections of this device in a few stages of its manufacture;
FIGS. 7 to 11 are cross-sections of a second embodiment of a semiconductor device according to the invention in a few stages of its manufacture; and
FIGS. 12 to 14 are cross-sections of a third embodiment of a semiconductor device according to the invention in a few stages of its manufacture.
It is noted that the drawing is diagrammatic only and not true to scale, and that in particular the dimensions in vertical direction are shown on an enlarged scale compared with the dimensions in other directions.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The semiconductor device of FIG. 1 may be a discrete transistor, no further active circuit elements being provided in the semiconductor device. Since the invention is of particular importance for transistors having very small dimensions, especially in the deep sub-micron region, however, the device as shown in FIG. 1 will usually form part of an integrated circuit with a very large number of circuit elements. The device comprises a semiconductor body 1 of silicon with a p-type surface region 3 adjoining a surface 2 . The semiconductor body 1 may have a doping throughout its thickness uniform with the doping concentration of the surface region 3 . In an alternative embodiment, as shown in FIG. 1, the p-type region is formed by a comparatively weakly doped layer epitaxially provided on a strongly doped p-type substrate 4 . The semiconductor body is provided with an insulated-gate n-channel field effect transistor or MOST. The transistor comprises two main electrode regions 5 and 6 in the form of n-type surface zones which form the source and drain zones of the transistor. The zones 5 and 6 are mutually separated by an interposed channel region 7 which adjoins the surface 2 and whose length lies in the deep sub-micron region, for example, 0.18 μm. The surface of the channel region is covered by a gate dielectric, for example an oxide layer 8 of, for example, 4 nm thickness, which separates the channel region from the gate electrode 9 . The doping concentration of the region 7 is very low compared with that of the other zones or regions. Accordingly, the channel region 7 will be considered a zone of intrinsic silicon hereinafter. The surface region 3 is in addition provided with a buried p-type zone 10 which extends below the channel region at a very small distance, i.e. at a distance of a few tens of nanometers from the surface 2 . The doping level of the buried zone is high, at least higher than that of the channel region 7 by a few orders of magnitude such that during operation the zone 10 may be regarded as an equipotential plane or ground plane.
According to the invention, the surface region 3 also comprises a buried layer 11 in which part of the Si atoms are replaced by Ge atoms. This layer will be referred to as Si 1−x Ge x hereinafter (x representing the molar fraction of Ge), or SiGe layer for short, but it should be borne in mind that other substituents may be found such as, for example, C, in addition to Ge in the crystal lattice. Diffusion of boron from the strongly doped layer 10 to the intrinsic region 7 is inhibited by the SiGe layer 11 . As a result, it is not necessary to carry out an additional As implantation into the region 7 , so that the mobility of the electrons at the surface remains high. The thickness of the SiGe layer may be chosen to be approximately 20 nm for a Ge content x of approximately 0.3. This thickness value, for which the layer 11 still acts as a satisfactory diffusion barrier, is so low that the lattice distances in the SiGe layer 11 are equal or at least substantially equal to those of Si in a direction parallel to the surface 2 . This means that the intrinsic region 7 can be provided epitaxially in a simple manner.
The source and drain zones 5 and 6 extend from the surface 2 to beyond the strongly doped zone 10 into the more weakly doped surface region 3 , so that the parasitic junction capacitance of these zones is kept low. To obtain a controlled overlap between the gate electrode 9 on the one hand and the source and drain zones on the other hand, the zones 5 and 6 are each provided with an extension 12 , 13 , respectively, whose thicknesses are smaller than those of the zones 5 and 6 .
The lateral boundary of the active region within the semiconductor body in this embodiment comprises grooves 14 which extend to a greater depth into the semiconductor body than do the source and drain zones and which are filled with oxide or with some other suitable material or combination of materials. The grooves 14 may be formed after the layer structure 10 , 11 , 7 has been formed without high-temperature steps which could disturb this layer structure.
FIGS. 2 to 4 show a few steps in the manufacture of the transistor of FIG. 1 . The drawing starts with the situation in which the surface region 3 in the form of a weakly doped p-type epitaxial layer with a doping concentration of, for example, 10 17 atoms per cm 3 and a thickness of between 1 and 3 μm has been provided on the (100) oriented surface of the strongly doped p-type substrate. The Si 1−x Ge x layer 11 is subsequently provided epitaxially, x being approximately 0.3 and the thickness of the layer approximately 20 nm. The layer 11 is furthermore intrinsic, i.e. the concentration of p-type or n-type dopants is kept as low as possible. Then the intrinsic Si layer 7 , from which the channel region is formed, is epitaxially provided on the SiGe layer 11 . The device in this stage of the process is shown in FIG. 2 . In a next step, the active regions are defined, for which an etching mask 15 is provided on the surface (FIG. 3 ), after which the grooves 14 are formed by anisotropic etching. A specific value for the width of the grooves 14 is, for example, 0.25 μm. The grooves are filled with oxide in a manner known per se, whereby a substantially plane surface is obtained. After removal of the mask 15 , the buried layer 10 is formed through a boron ion implantation with a doping of, for example, 10 13 atoms per cm 2 and an energy of 25 keV (FIG. 4 ), whereby a thin, strongly doped p-type layer is obtained with a maximum doping of approximately 10 18 boron atoms per cm 3 . Damage in the crystal lattice may be eliminated by means of a RTA (Rapid Thermal Anneal) treatment, for example a heating step at 950° C. for 25 s. The gate oxide 8 is subsequently provided to a thickness of approximately 4 nm by thermal oxidation at a temperature of, for example 850° C. This stage is shown in FIG. 4 .
During the RTA step mentioned above and the oxidation step, the boron in the buried layer 10 has a tendency to diffuse towards the surface. It was found, however, that boron diffusion is effectively decelerated by the SiGe layer, so that the B concentration in the channel region remains low, at least much lower than if the SiGe layer were absent, and the channel region may be regarded as intrinsic also without a compensatory As implantation. The SiGe layer itself may become weakly p-type doped through diffusion of boron. In a next step, a polycrystalline or amorphous silicon layer is deposited to a thickness of approximately 0.2 μm, which may be patterned in a usual manner so as to obtain the gate electrode 9 , FIG. 5 . The length of the gate electrode is, for example, 0.18 μm. An implantation, diagrammatically indicated with arrows 16 , is then carried out to form As-doped regions 17 from which the source/drain extensions 12 and 13 are created after heating. The implantation is carried out, for example, at a density of 10 14 atoms per cm 2 and an implantation energy of approximately 10 keV. The depth of the zone obtained, and thus also the overlap with the gate 9 are very small at this energy, so that the effective channel length corresponds substantially to the length of the gate electrode. The gate electrode 9 may also be doped simultaneously with this implantation. Subsequently, the spacers 18 (FIG. 6) are formed on the flanks of the gate electrode 9 in a usual manner, for example through deposition and anisotropic etching-back of a layer of silicon oxide or silicon nitride. Then As ions are implanted again so as to obtain the deep source and drain zones 5 and 6 with the spacers 18 acting as an implantation mask. The implantation is carried out with an energy of, for example, 70 keV and a dose of 4×10 15 per cm 2 . The gate electrode 9 may also be doped simultaneously with this step. Then a heating step is carried out to eliminate damage in the crystal caused by the implantation and to activate the implantated As ions. RTA is preferably used for this again in order to limit the diffusion of As as much as possible.
Contacts may be provided in a next stage, for example in the form of salicide contacts 19 , for which purpose a 30 nm thick Ti layer is deposited, after which the device is heated in an ambience comprising nitrogen. A silicide layer with a thickness of approximately 50 nm arises then in locations where Ti is in contact with Si, while in other 15 locations titanium nitride is formed which may be readily removed selectively, so that the device as depicted in FIG. 1 is obtained.
FIG. 11 is a cross-section showing a CMOST device according to the invention. The device comprises besides the n-channel transistor T 1 a transistor T 2 complementary thereto, i.e. a p-channel transistor. Transistor T 1 has a construction corresponding to that of the transistor of the preceding embodiment and is accordingly given the same numerals for ease of reference. The transistor again comprises an intrinsic channel region 7 which is separated from the strongly doped p-type ground plane layer 10 by the SiGe layer 11 , analogous to the preceding example. The p-channel field effect transistor T 2 comprises an n-type well 23 in which the p-type source and drain zones 25 and 26 are situated. Between the source and drain zones lies the channel region 27 which has a very low doping concentration, analogous to the channel region 7 , and which is accordingly regarded as an intrinsic semiconductor region again hereinafter. The gate electrode 29 is provided above the channel region 27 . A ground plane region is provided at a very small distance from the surface, taking the form of a thin, strongly doped n-type zone 30 which merges into the intrinsic region 27 via a SiGe layer 31 . In general, SiGe has the property that it accelerates the diffusion of n-type impurities instead of decelerating it, as in the case of boron. This is why As is used as the dopant for the n-type ground plane 30 . As will diffuse at an accelerated rate into the SiGe layer 31 during the various process steps, such as the formation of the gate oxide, so that this layer 31 will become comparatively strongly n-type doped. As, however, has a very low diffusion rate in Si, so that the diffusion is practically stopped at the boundary between the SiGe layer 31 and the—intrinsic—channel region 27 .
The manufacture of the device of FIG. 11 is described with reference to FIGS. 7 to 10 which show a few stages in the process. The process starts again with a strongly doped p-type silicon substrate 40 on which a less strongly doped p-type epitaxial layer 41 is formed with a concentration of between 10 14 and 10 15 atoms per cm 3 . It is noted that the low-ohmic substrate 40 is shown in FIG. 7 only, not in FIGS. 8 to 10 . A p-type well 3 for the n-channel transistor and an n-type well 42 for the p-channel transistor are formed in the semiconductor body 1 obtained as above in a usual manner, see FIG. 7 . The thicknesses of the p-well 3 and of the n-well 42 may have values of between 1 and 3 μm. The average doping concentration is, for example, 10 17 atoms per cm 3 . An approximately 20 nm thick SiGe layer 11 and an approximately 30 nm intrinsic Si layer 7 are then epitaxially provided in the manner as described with reference to the preceding embodiment, see FIG. 8 . The same composition may be chosen for the SiGe layer 11 as in the preceding embodiment. Then grooves 14 are provided (FIG. 9) between the regions 3 and 42 , subdividing the intrinsic Si layer 7 and the SiGe layer into a number of separate portions.
In a next stage shown in FIG. 10, the strongly doped p-type layer 10 and the strongly doped n-type layer 30 are provided below the SiGe layer 11 by means of consecutive masked implantation steps. The layer 10 , which has a thickness of, for example, 30 nm, is provided through implantation of boron with an implantation energy of approximately 25 keV and a dose of approximately 10 13 atoms per cm 2 . The n-type ground plane 30 is formed through implantation of As with an energy of approximately 150 keV and a dose of again approximately 10 13 atoms per cm 2 . After the implantation steps, an RTA treatment is carried out at a temperature of approximately 950° C. for approximately 25 seconds so as to activate the B and As atoms and restore damage in the crystal. The gate oxide 8 is formed in the subsequent oxidation step in the manner as described with reference to the preceding embodiment. Diffusion of boron atoms from the strongly doped layer 10 is decelerated by the SiGe layer 11 during this thermal step, so that the doping level in the channel region 7 remains very low. The As atoms in the strongly doped layer 30 of the p-channel MOST do diffuse into the SiGe layer, whereby the comparitively strongly doped n-type SiGe layer 31 is formed in transistor T 2 . Since the diffusion rate of As in Si is very low, however, the diffusion of As stops practically at the boundary between the SiGe layer 31 and the Si layer 7 . As a result, the doping concentration in the channel region of the p-channel transistor also remains very low, and the advantages of the ground plane configuration in the n-channel transistor are thus also obtained in the p-channel transistor T 2 .
After the gate oxide 8 has been formed, an undoped poly layer is deposited from which the gates 9 of T 1 and 29 of T 2 are formed. The n-type source and drain zones 5 and 6 of the n-channel transistor T 1 and the p-type source and drain zones 25 and 26 of the p-channel transistor T 2 are formed through consecutive masking and doping steps. The same values as in the preceding embodiment may be used for the dosing and implantation energy of the n-type dopant for making the source and drain zones of the n-channel transistor T 1 . The extensions of the source and drain zones 25 , 26 of the p-channel transistor T 2 may be formed through implantation of BF 2 ions with a dose of approximately 5×10 14 ions per cm 2 and an energy of approximately 5 keV. The deep zones may be formed through implantation of BF2 with a dose of approximately 2.5×10 15 ions per cm 2 and an energy of approximately 20 keV. The gate 29 may be p-type doped simultaneously with either or both implantations. After an RTA treatment, which is as short as possible so as to prevent the diffusion of impurities as much as possible, silicide contacts may again be provided on the source and drain zones and gate electrodes in the manner described above, after which further usual steps can be carried out, such as the provision of insulating layers and wiring.
Grooves were used for the boundaries of the active regions in the examples described above, possibly filled up with a suitable substance for obtaining a plane surface. FIGS. 12 to 14 show in cross-section an embodiment in which the active regions are bounded by a conventional field oxide which may be obtained by means of a LOCOS process known per se. FIG. 12 shows the situation where the semiconductor body has been provided with a pattern 33 of silicon oxide with a thickness of approximately 0.3 μm forming the field oxide at its surface by means of masked oxidation. The p-type well 3 and the n-type well 23 may then be provided through ion implantation. Subsequently, the SiGe layer 11 and the intrinsic Si layer 7 are deposited in the active regions between the oxide layers 33 by selective epitaxy, see FIG. 13 . The thickness and the composition of the SiGe layer 11 and the thickness of the intrinsic layer 7 correspond to the thickness and composition of the SiGe layer 11 and Si layer 7 in the first embodiment. In a next series of steps, the strongly doped n-type ground plane 30 and p-type ground plane 10 are then provided below the SiGe layer 11 at a short distance from the surface. This stage is shown in FIG. 14 . The process may be continued as in the preceding embodiment with the growth of the gate oxide, followed by the formation of the gate electrodes and the source and drain zones as described above.
It will be obvious that the invention is not limited to the embodiments described here, but that many more variations are possible to those skilled in the art within the scope of the invention. Thus, for example, the sequence of the various process steps may be changed in the examples described, for example, the implantation for the ground plane may be carried out first, and the SiGe layer and the intrinsic layer may be provided epitaxially afterwards. If the SiGe layer and the intrinsic layer are provided through selective epitaxy, it is possible to mask the semiconductor body locally against epitaxy where said layers are not necessary, for example in locations where bipolar transistors will be formed.
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To obtain a high mobility and a suitable threshold voltage in MOS transistors with channel dimensions in the deep sub-micron range, it is desirable to bury a strongly doped layer (or ground plane) in the channel region below a weakly doped intrinsic surface region, a few tens of nm below the surface. It was found, however, that degradation of the mobility can occur particularly in n-channel transistors owing to diffusion of boron atoms from the strongly doped layer to the surface, for example during the formation of the gate oxide. To prevent this degradation, a thin layer 11 of Si 1−x Ge x inhibiting boron diffusion is provided between the strongly doped layer 10 and the intrinsic surface region 7 , for example with x=0.3. The SiGe layer and the intrinsic surface region may be provided epitaxially, the thickness of the SiGe layer being so small that the lattice constants in the epitaxial layers do not or substantially not differ from those in the substrate 1 in a plane parallel to the surface, while a sufficient diffusion-inhibiting effect is retained. Since SiGe has a diffusion-accelerating rather than decelerating effect on n-type dopants, the ground plane of a p-channel transistor in a CMOS embodiment is doped with As or Sb because of the low diffusion rate of these elements in pure silicon.
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BACKGROUND
1. Field of the Invention
The present invention relates to user interfaces for computer systems. More particularly, the present invention relates to a method and apparatus for viewing a collection of objects on a display that allows a user to “scroll” through the objects by varying non-positional display attributes for objects, such transparency, color or size, instead of varying spatial location.
2. Related Art
One of the scarcest resources in today's computing devices is screen space. Even though the processing power and storage capacity of computing devices has increased by several orders of magnitude during the past twenty years, the average computer screen size has barely doubled. Although the resolution, clarity, and the overall quality of the displays has improved substantially, the actual size of the work area remains relatively limited. Screen space limitations are particularly apparent in the emerging pocket-sized computing devices and personal organizers. These pocket-sized computing devices often have display sizes that are less than a few hundred or a few thousand square pixels.
Spatial scrolling is a conventional and useful way to deal with limited screen real estate. When a user runs out of screen space, the user can scroll the display so that old objects move off the screen and new screen space becomes available. Conventional “spatial scrolling” suffers from a number of problems that undermine the benefits of the windows-icons-desktop-folders metaphor presently used in most user interfaces.
One problem is that spatial scrolling undermines spatial memory. User interfaces based upon the windows-icons-desktop-folders metaphor have proven quite powerful because they allow a user to organize data by placing icons at various “locations” on a computer display. Human users tend to have good “spatial memory,” which allows them to remember that particular items are located at specific locations on a display. Spatial scrolling undermines spatial memory because objects move as they scroll across a display.
Another problem with spatial scrolling is “discontinuous salience.” “Salience” is a measure of the prominence of an object in a display, in other words how much the object stands out from the rest of the display. As objects grow larger or become brighter they become more salient. However, when an object moves off the screen, its salience drops to zero. For example, in the case of three-dimensional scrolling, an object becomes increasingly salient as the object moves closer to the reference point of the display. However, salience drops to zero as the object passes through the forward clipping plane of the display. Furthermore, two objects that are close together in three-dimensional space appear to diverge and move apart across the screen as the reference point of the display moves closer to the objects.
What is needed is a method for scrolling through objects in a graphical display that preserves spatial memory and continuity of salience.
SUMMARY
One embodiment of the present invention provides a system for viewing objects on a display that allows a user to scroll through the objects by varying a non-positional display attribute of the objects. This non-positional display attribute may include attributes such as transparency, fadedness and size. The system operates by receiving an intrinsic value for an object, which specifies a value for a display attribute associated with the object. The system also receives a reference value for the display attribute against which intrinsic values for objects are compared. This reference value may be received from a user, for example through a scroll bar that is manipulated by the user. The system uses the intrinsic value and the reference value to compute a display value for the object. Next, the object is displayed using the display value to specify the non-positional display attribute for the object.
In one embodiment of the present invention, computing the display value for the object includes computing a difference between the intrinsic value for the object and the reference value. In a further variation, the function used to compute the display value is continuous and assumes a higher value when the absolute value of the difference approaches zero, and a lower value when the absolute value of the difference becomes large.
In one embodiment of the present invention, display values are computed for the objects before any objects are displayed. Next, the objects are sorted by display value and displayed in sorted order. This ensures that objects with smaller display values are not displayed on top of objects with larger display values.
In one embodiment of the present invention, objects that have the same value for a display attribute belong to the same “layer” and are hence displayed at the same time. Objects that have an intrinsic value equal to reference value are displayed normally (opaquely) without any fading. Other objects that have a display value close the reference value are displayed translucently, giving the impression that objects are “emerging from the fog” or gradually “fading away.” Objects with a large difference between the intrinsic value of the object and the reference value are not displayed at all. This entire process is fully reversible and repeatable. Hence, a user can move the reference value higher and lower, viewing objects with different intrinsic values at varying levels of fading.
In one embodiment of the present invention, visualization of objects is implemented cumulatively. This means when the user moves the reference value higher, the display behaves as described above. However, when the user moves the reference value lower, the display shows cumulatively more and more objects until all possible objects become visible.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 illustrates a computing device in accordance with an embodiment of the present invention.
FIG. 2 illustrates one form of stationary scrolling in accordance with an embodiment of the present invention.
FIG. 3 illustrates another form of stationary scrolling in accordance with an embodiment of the present invention.
FIG. 4 illustrates how computer system components connect with the visualization subsystem in accordance with an embodiment of the present invention.
FIG. 5 illustrates the structure of the visualization subsystem in accordance with an embodiment of the present invention.
FIG. 6 is a flow chart illustrating the process of displaying objects in accordance with an embodiment of the present invention.
FIG. 7 is a flow chart illustrating how objects are sorted by display value to establish a display order in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
The following description is presented to enable any person skilled in the art to make and use the invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present invention. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles and features disclosed herein.
The data structures and code described in this detailed description are typically stored on a computer readable storage medium, which may be any device or medium that can store code and/or data for use by a computer system. This includes, but is not limited to, magnetic and optical storage devices such as disk drives, magnetic tape, CDs (compact discs) and DVDs (digital video discs), and computer instruction signals embodied in a carrier wave. For example, the carrier wave may carry information across a communications network, such as the Internet.
Computer System
FIG. 1 illustrates computing device 102 in accordance with an embodiment of the present invention. Computing device 102 may include any type of computing device with a display, including a personal computer, a workstation or a mainframe computer system. Computing device 102 may additionally include portable computing devices, such as a personal organizer, a two-way pager, a cellular telephone or a mobile web browser.
Computing device 102 includes a display 104 for outputting data to a user. Computing device 102 also includes a number of input devices, including keyboard 106 and mouse 108 , for receiving input from the user. Note that many other types of input devices can be used with the present invention, including input buttons on a personal organizer or a touch sensitive display. Display 104 may include any type of display device on a computer system, including but not limited to, a cathode ray tube, a flat panel display, a LCD display or an active matrix display.
Computing device 102 also includes software architecture 120 . At the lowest level, software architecture 120 includes operating system 128 , which supports the execution of applications on computing device 102 . In one embodiment of the present invention, operating system 128 includes the WINDOWS operating system distributed by the Microsoft Corporation of Redmond, Wash. In another embodiment, operating system 128 includes the Palm OS that is contained within the Palm connected organizer, distributed by the 3COM corporation of Sunnyvale, Calif.
Alongside operating system 128 is graphics routines 124 . Graphics routines 124 include any routines for facilitating the generation of images on display 104 .
User interface 122 resides on top of operating system 128 and graphics routines 124 . User interface 122 interacts with operating system 128 and graphics routines 124 to provide an output to display 104 in accordance with an embodiment of the present invention.
Finally, applications 121 reside on top of user interface 122 . Applications 121 may include any type of applications running on computing device 102 that can be used in conjunction with user interface 122 .
Computing device 102 also includes hardware architecture 130 . Hardware architecture 130 includes processor 132 , memory 134 , display 104 , secondary storage device 136 , input devices 138 and communication interface 137 . These components are coupled together by bus 133 . Processor 132 may include any type of computational engine for executing programs within computing device 102 . This includes, but is not limited to, a microprocessor, a device controller, and a computational device within an appliance. Memory 134 may include any type of random access memory for storing code and data for use by processor 132 . Secondary storage device 136 may include any type of non-volatile storage device for storing code and data to for use by processor 132 . This includes, but is not limited to, magnetic storage devices, such as a disk drive, and electronic storage devices, such as flash memory or battery backed up RAM. Display 104 (described above) may include any type of device for displaying images on a computer system. Input devices 138 may include any type of devices for inputting data into computing device 102 . This includes keyboard 106 and mouse 108 as well as input buttons or a touch-sensitive display. Communication interface 137 may include any type of mechanism for communicating between computing device 102 and an external host. This may include a linkage to a computer network through electrical, infrared or radio signal communication pathways.
Stationary Scrolling
FIG. 2 illustrates one form of stationary scrolling in accordance with an embodiment of the present invention. In this embodiment, a number of objects 204 , 206 , 208 and 210 appear on display 104 . Each of these objects has an “intrinsic value” for a particular display attribute. This intrinsic value is combined with a reference value for the attribute to produce a display parameter for the object. FIG. 2 presents three representations of display 104 , a top display, a middle display and a bottom display, which depict display 104 at different points in time as slider 202 moves in a downward direction.
In the top display 104 , objects 204 , 208 and 210 are drawn with dashed lines. This indicates that objects 204 , 208 and 210 have less salience than object 206 , which is drawn with solid lines. Because objects 204 , 208 and 210 have less salience, they appear more faded (or more transparent) than object 206 .
Note that fading of an object can be implemented in different ways. Color or grayscale levels can be varied when drawing the object. Pixels of the object can be selectively changed to either blank or transparent while the object is being drawn. Alternatively, a predefined set of icons with varying levels of fadedness can be pre-defined for each type of display object.
Note that a user can change a scrolling reference value for the display by moving slider 202 up or down using a pointing device such as mouse 108 .
In middle display 104 , slider 202 has been moved in a downward direction so that the scrolling reference value is closer to intrinsic values for objects 208 and 210 . Hence, objects 208 and 210 have greater salience and are drawn with solid lines. At the same time, the scrolling reference value is farther from the intrinsic value for object 206 . Hence, object 206 has less salience so it is drawn with dashed lines. The scrolling reference value has also moved closer to the intrinsic value for object 204 . Hence object 204 has more salience, but not as much as objects 208 and 210 , so object 204 is still drawn with dashed lines.
In bottom display 104 , slider 202 has been moved even further downward so that the scrolling reference value is closer to the intrinsic value for object 204 . Hence, object 204 has greater salience and is drawn with solid lines. Objects 206 , 208 and 210 have less salience, and are drawn with dashed lines.
Note that the spatial locations of objects 204 , 206 , 208 and 210 are preserved because objects 204 , 206 208 and 210 do not move. However, objects 204 , 206 , 208 and 210 may become less visible or even invisible as they fade or become more transparent.
Also note that discontinuity of salience is no longer a problem. An object becomes increasingly more salient as the scrolling reference value controlled by slider 202 comes closer to the intrinsic value of the object. A point of maximum salience is reached when the intrinsic value matches the scrolling reference value. When the scrolling reference value moves past the intrinsic value, salience gradually tails off and the object gradually fades or becomes more transparent. In one embodiment of the present invention, if the salience of an object falls below a threshold value, the object is no longer visible.
In one embodiment of the present invention, an object can be selected to remain at a fixed salience value (typically the maximum salience value) as the scrolling reference value changes. Hence, the display for this “fixed” object will not change as other objects in the display fade or become more transparent.
FIG. 3 illustrates another form of stationary scrolling in accordance with another embodiment of the present invention. In the embodiment illustrated in FIG. 3, salience is represented by relative sizes of objects. As the salience of an object increases, the object grows larger. Conversely, as the salience of an object decreases the object becomes smaller.
For example, in FIG. 3, in top display 104 , object 304 has a large salience, and is hence represented by a large square. In middle display 104 and bottom display 104 , as slider 202 moves downward the salience of object 304 diminishes because the scrolling reference value controlled by slider 202 moves away from the intrinsic value of object 304 . Hence, the size of object 304 decreases.
For object 302 the reverse is true. In top display 104 , object 302 has a low salience value and is represented by a small circle. In middle display 104 and bottom display 104 , as slider 202 moves downward, the salience of object 302 increases. Hence, the size of object 302 increases.
Objects 306 and 308 behave differently. They have the highest salience in middle display 104 and are hence represented by large triangles. In the top display 104 and the bottom display 104 , the salience of objects 306 and 308 decreases, hence the size of objects 306 and 308 decreases.
Scrolling of both the stationary variety and the non-stationary variety can be described more formally as follows. Consider a set of displayable objects, 0={O i }with each element O i located in an abstract N-dimensional space, S. The location of each object O i in this space is an N-dimensional vector, x. We call vector x the display location in S. The numbers in x determine how an object appears on the screen, and therefore affect the salience of the object as perceived by the user.
The components of x may represent visual characteristics such as horizontal and vertical position on the screen, transparency, fadedness, and size. Note these visual characteristics affect the objects salience, but not its identity: moving an object through this space S will not substantially affect the user's perception of what the object is, merely how it looks. For example, simply changing the position of a document icon does not change the user's ability to identify it, whereas scrambling the colors, replacing the shape, and embedding an arbitrary bitmap in its surface may make identification difficult.
The components of x may also represent other display attributes, such as shape, saturation of color, hue, the speed with which the object blinks or wiggles, the degree to which the object is in focus or blurred, the thickness of the object's outline, and so forth.
To define scrolling, we associate with the user with a scrolling reference parameter p in S. In conventional text scrolling for example, p is a single number representing the vertical offset of the user's current view into the document: the value of p is determined by the position of the scroll bar. In one possible definition for scrolling, set 0 is scrollable if each object O i also has an intrinsic location x I , in S which is related to the display location x through the scrolling reference parameter, p,and a scrolling function,f. In other words, x=f(x I −p).
Both f and p are in general vectors so they may affect more than one aspect of the display location. Furthermore, in order to be useful in a conventional way, f(x) usually takes on values associated with greatest salience at or near x=0.
An infinite number of different functions may be used for f. These functional preferably have the greatest value (or salience) when the absolute value of x I −p is small, and a smaller value when the absolute value of xI−p is large. In this way, an object's salience will be greatest when the user's scrolling reference value is closest to the intrinsic value of the object. Also, these functions are preferably smoothly varying to preserve continuity of salience. For example, the function can be f(x)=Aexp(−x 2 /r 2 ) or f(x)=c 2 /(c 2 +x 2 ). Both of these are smoothly varying functions that reach a peak when x=0.
Visualization Subsystem
FIG. 4 illustrates how components in computing device 102 connect with visualization subsystem 404 in accordance with an embodiment of the present invention. Visualization subsystem 404 handles drawing and outputting of objects to display 104 . As part of these duties, visualization subsystem 404 implements stationary scrolling.
Visualization subsystem 404 is coupled to application specific logic and data 406 , which contains code and data to implement the underlying non-visual functions of an application. For example, application specific logic and data 406 can compute a bank account balance, while visualization subsystem 404 can display the bank account balance.
Both visualization subsystem 404 and application-specific code and logic 406 receive input from input/event dispatcher 402 , which itself receives input from a user operating input devices 138 . Input devices 138 may include, for example, keyboard 116 and mouse 108 from FIG. 1 . Finally, visualization subsystem 404 outputs images of the objects to display 104 .
FIG. 5 illustrates the internal structure of visualization subsystem 404 in accordance with an embodiment of the present invention. Visualization subsystem 404 includes window displayer 502 , which controls the displaying of objects in display 104 .
Window displayer 502 communicates with scrollable view 504 and user input module 524 . Scrollable view 504 controls the scrolling of a collection of display objects. In the embodiment illustrated in FIG. 3, scrollable view 504 controls display objects 506 , 512 and 518 . Each display object contains a number of display attributes containing numbers. These display attributes may specify color, size and positional attributes for the object. More specifically, display object 506 includes display attributes 508 , display object 512 includes display attributes 514 , and display object 518 includes display attributes 520 .
Display objects 506 , 508 and 510 are also associated with other non-display related data, such as bank account balances, contained in application-specific data and logic 406 . More specifically, display object 506 is associated with other data 510 , display object 512 is associated with other data 516 , and display object 518 is associated with other data 522 .
In order to compute the above-described functions, window displayer 502 accesses scrolling reference value 526 through user input module 524 . A user may enter a scrolling reference value 526 by moving slider 202 (from FIG. 2) using mouse 108 (from FIG. 1 ). This causes input/event dispatcher 402 to send scrolling reference value 526 through window displayer 502 into user input module 524 . User input module 524 finally stores scrolling reference value 526 .
Window displayer 502 also includes methods to calculate display values for display objects 506 , 512 and 518 based on scrolling reference value 526 .
Process of Displaying Objects
FIG. 6 is a flow chart illustrating the process of displaying objects in accordance with an embodiment of the present invention. The system starts by drawing a background against which the objects are to be displayed (step 601 ). Drawing this background may include blanking out or overwriting an existing display. For each object to be displayed, the system gets an intrinsic value for the object, which is a value for a non-positional display attribute (step 602 ). The system also receives a scrolling reference value 526 (step 604 ). This scrolling reference value 526 may be received from a user through a user interface, such as slider 202 in FIG. 1 . Alternatively, scrolling reference value 526 may be taken from another source, such as a system clock. Next, the system uses a function to compute a display value for the object based upon the intrinsic value for the object and the scrolling reference value 526 . Recall that this display value may be calculated as a function of the difference between the object's intrinsic value and the scrolling reference value 526 . Finally, the object is displayed using the calculated display value to specify the non-positional display attribute (step 608 ).
FIG. 7 is a flow chart illustrating how objects are sorted by display value to establish a display order in accordance with an embodiment of the present invention. It is desirable for objects with greater salience to be displayed more prominently than objects with less salience. Hence, it is desirable for objects with greater salience to be drawn later than objects with less salience, so that objects with less salience do not cover or obscure objects with greater salience. To this end, it is desirable to draw objects in increasing order of salience. The system accomplishes this by first computing display values for all objects in the display (step 702 ). After the display values have been computed, the system sorts the objects in ascending order of display value (step 704 ). Finally, the system draws the objects on the display in increasing order of display value from lowest display value to highest display value.
The foregoing descriptions of embodiments of the invention have been presented for purposes of illustration and description only. They are not intended to be exhaustive or to limit the invention to the forms disclosed. Accordingly, many modifications and variations will be apparent to practitioners skilled in the art. Additionally, the above disclosure is not intended to limit the invention. The scope of the invention is defined by the appended claims.
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One embodiment of the present invention provides a system for viewing objects on a display that allows a user to scroll through the objects by varying a non-positional display attribute of the objects. This non-positional display attribute may include attributes such as transparency, fadedness and size. The system operates by receiving an intrinsic value for an object, which specifies a value for a display attribute associated with the object. The system also receives a reference value for the display attribute against which intrinsic values for objects are compared. This reference value may be received from a user through a scroll bar that is manipulated by the user. The system uses the intrinsic value and the reference value to compute a display value for the object. Next, the object is displayed using the display value to specify the non-positional display attribute for the object. Thus, in one embodiment of the present invention, objects that have an intrinsic value equal to reference value are displayed normally (opaquely) without any fading. Other objects that have a display value close the reference value are displayed translucently, giving the impression that objects are “emerging from the fog” or gradually “fading away.” Objects with a large difference between the intrinsic value of the object and the reference value are not displayed at all.
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FIELD OF THE INVENTION
[0001] This invention relates to the field of balloons that are useful in angioplasty and other medical uses.
BACKGROUND OF THE INVENTION
[0002] Catheters having inflatable balloon attachments have been used for reaching small areas of the body for medical treatments, such as in coronary angioplasty and the like. Balloons are exposed to large amounts of pressure. Additionally, the profile of balloons must be small in order to be introduced into blood vessels and other small areas of the body. Therefore, materials with high strength relative to film thickness are chosen. An example of these materials is PET (polyethylene terephthalate), which is useful for providing a non-compliant, high-pressure device. Unfortunately, PET and other materials with igh strength-to-film thickness ratios tend to be scratch- and puncture-sensitive. Polymers that tend to be less sensitive, such as polyethylene, nylon, and urethane are compliant and, at the same film thickness as the non-compliant PET, do not provide the strength required to withstand the pressure used for transit in a blood vessel and expansion to open an occluded vessel. Non-compliance, or the ability not to expand beyond a predetermined size on pressure and to maintain substantially, a profile, is a desired characteristic for balloons so as not to rupture or dissect the vessel as the balloon expands. Further difficulties often arise in guiding a balloon catheter into a desired location in a patient due to the friction between the apparatus and the vessel through which the apparatus passes. The result of this friction is failure of the balloon due to abrasion and puncture during handling and use and also from over-inflation.
[0003] The present invention is directed to a non-compliant medical balloon suitable for angioplasty and other medical procedures and which integrally includes very thin inelastic fibers having high tensile strength, and methods for manufacturing the balloon. The fiber reinforced balloons of the present invention meet the requirements of medical balloons by providing superior burst strength; superior abrasion-, cut- and puncture-resistence; and superior structural integrity.
[0004] More particularly, the invention is directed to a fiber-reinforced medical balloon having long axis, wherein the balloon comprises an inner polymeric wall capable of sustaining pressure when inflated or expanded into a fiber/polymeric matrix outer wall surrounding and reinforcing the inner polymeric wall. The fiber/polymeric matrix outer wall is formed from at least two layers of fibers and a polymer layer. The fibers of the first fiber layer are substantially equal in length to the length of the long axis of the balloon and run along the length of the long axis. But “substantially equal in length” is meant that the fiber is at least 75% as long as the length of the long axis of the balloon, and preferably is at least 90% as long. The fiber of the second fiber layer runs radically around the circumference of the long axis of the balloon substantially over the entire length of the long axis. By “substantially over the entire length” is meant that the fiber runs along at least the center 75% of the length of the long axis of the balloon, and preferably runs along at least 90% of the length. The fiber of the second fiber layer is substantially perpendicular to the fibers of the first fiber layer. By “substantially perpendicular to” is meant that the fiber of the second fiber layer can be up to about 10 degrees from the perpendicular.
[0005] The invention is further directed to processes for manufacturing a non-compliant medical balloon. In one embodiment, a thin layer of a polymeric solution is applied over a mandrel, the mandrel having the shape of a medical balloon and being removable from the finished product. High-strength inelastic fibers are applied to the thin layer of polymer with a first fiber layer having fibers running substantially along the length of he long axis of the balloon and a second fiber layer having fiber running radially around the circumference of the long axis substantially over the entire length of the long axis. The fibers are then coated with a thin layer of a polymeric solution to form a fiber/polymeric matrix. The polymers are cured and the mandrel is removed to give the fiber-reinforced medical balloon.
[0006] In another embodiment of the invention, a polymer balloon is inflated and is maintained in its inflated state, keeping the shape of the balloon. High-strength inelastic fibers are applied to the surface of the balloon, with a first fiber layer having fibers running substantially along the length of the long axis of the balloon and a second fiber layer having fiber running radially around the circumference of the long axis substantially over the entire length of the long axis. The fibers are then coated with a thin layer of a polymeric solution to form a fiber/polymeric matrix. The fiber/polymeric matrix is cured to give the fiber-reinforced medical balloon, which can then be deflated for convenience, until use.
[0007] In a presently preferred embodiment, a thin coating of an adhesive is applied to the inflated polymer balloon or to the polymer-coated mandrel prior to applying the inelastic fibers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 illustrates an inflated standard medical balloon, which is used in the invention as the base of the final composite fiber-reinforced balloon.
[0009] FIG. 2 illustrates an inflated standard medical balloon, which is used in this invention as the base of the final composite fiber-reinforced balloon.
[0010] FIG. 3 illustrates the positioning of the second layer of fiber over the first fiber layer. The fiber is wound radially around the long axis substantially over the entire length of the long axis of the balloon, each wrap being substantially equally spaced from the others. The fiber runs substantially perpendicular to the fibers of the first fiber layer.
[0011] FIG. 4 illustrates the positioning of the third layer of fiber over the second fiber layer, in accordance with another embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0012] Referring now to the drawings, wherein like reference numbers are used to designate like elements throughout the various views, several embodiments of the present invention are further described. The figures are not necessarily drawn to scale, and in some instances the drawings have been exaggerated or simplified for illustrative purposes only. One of ordinary skill in the art will appreciate the many possible applications and variations of the present invention based on the following examples of possible embodiments of the present invention.
[0013] A medical balloon in accordance with the present invention in one embodiment begins with an inflated polymeric balloon 2 , as shown in FIG. 1 , to which there is applied by hand or mechanically, inelastic fiber or filament 4 , as shown in FIG. 2 . This is sometimes referred to as the “primary wind.” To assist in placement and retention of the fibers, there can be applied an adhesive to either the inflated balloon surface or to the fiber. The purpose of this first application of fiber is to prevent longitudinal extension (growth) of the completed balloon.
[0014] An alternate method of applying the longitudinal fibers involves first creating a fabric of longitudinal fibers by pulling taut multiple parallel fibers on a flat plate and coating with a polymeric solution to create a fabric. The fabric is then cut into a pattern such that it can be wrapped around the base balloon or mandrel.
[0015] Next, a second application of inelastic fiber 6 is applied to the circumference of the balloon, as shown in FIG. 3 . This is sometimes referred to as the “hoop wind.” The purpose of the hoop wind is to prevent or minimize distension of the completed balloon diameter during high inflation pressures.
[0016] After the hoop wind is completed, the exterior of the fiber-wound inflated balloon is coated with a polymeric solution and cured to form a composite, con-compliant fiber-reinforced medical balloon. The outer polymeric coating of the fiber/polymeric matrix secures and bonds the fibers to the underlying inflated balloon so that movement of the fibers is restricted during deflation of the composite balloon and subsequent inflation and deflation during use of the balloon. The polymeric solution can be applied several times, if desired. The polymeric solution can use the same polymer as or a polymer different from the polymer of the inflated polymeric balloon 2 . The polymers should be compatible so that separation of the composite balloon is prevented or minimized.
[0017] In a second method of making a medical balloon of the present invention, a removable mandrel having the shape that is identical to the shape of the inside of the desired balloon is used. A shape such as shown in FIG. 1 is suitable. The mandrel can be made of collapsible metal or polymeric bladder, foams, waxes, low-melting metal alloys, and the like. The mandrel is first coated with a layer of a polymer, which is then cured. This forms the inner polymeric wall of the balloon. Next, repeating the steps as described above, the primary wind and the hoop wind are placed over the inner polymer wall, followed by a coating with a polymeric solution and curing thereof to form a fiber/polymeric matrix outer wall. Finally, the mandrel is removed, by methods known in the art such as by mechanical action, by solvent, or by temperature change, to give the composite medical balloon of the invention.
[0018] In view of the high strength of the balloons of the present invention, it is possible to make balloons having a wall thickness less than conventional or prior art balloons without sacrifice of burst strength, abrasion resistence, or puncture resistance. The balloon wall thickness can be less than the thickness given in the examples hereinbelow.
[0019] In addition, the fiber-reinforced balloons of the present invention are non-complaint. That is, they are characterized by minimal axial stretch and minimal radial distention and by the ability not to expand beyond a predetermined size on pressure and to maintain substantially a profile.
[0020] Polymers and copolymers that can be used for the base balloon and/or the covering layer of the fiber/polymeric matrix include the conventional polymers and copolymers used in medical balloon construction, such as, but not limited to, polyethylene, polyethylene terephthalate (PET), polycaprolactam, polyesters, polyethers, polyamides, polyurethanes, polyimides, ABS copolymers, polyester/polyether block copolymers, ionomer resins, liquid crystal polymers, and rigid rod polymers.
[0021] The high-strength fibers are chosen to be inelastic. By “inelastic,” as used herein and in the appended claims, is meant that the fibers have very minimal elasticity or stretch. Zero elasticity or stretch is probably unobtainable taking into account the sensitivity of modern precision test and measurement instruments, affordable costs and other factors. Therefore, the term “inelastic” should be understood to mean fibers that are generally classified as inelastic but which, nevertheless, may have a detectable, but minimal elasticity or stretch. High strength inelastic fibers useful in the present invention include but are not limited to; Kevlar, Vectran, Spectra, Dacron, Dyneema, Terlon (PBT), Zylon (PBO), Polyimide (PIM), ultra high molecular weight polyethylene, and the like. In a presently preferred embodiment, the fibers are ribbon-like; that is, they have a flattened to a rectangular shape. The fibers of the first fiber layer may be the same as or different from the fiber of the second fiber layer.
[0022] The most advantageous density of the fiber wind is determinable through routine experimentation by one of ordinary skill in the art given the examples and guidelines herein. With respect to the longitudinally-placed fibers (along the long axis of the balloon) of the first fiber layer, generally about 15 to 30 fibers having a fiber thickness of about 0.0005 to 0.001 inch and placed equidistant from one another will provide adequate strength for a standard-sized medical balloon. With respect to the fiber of the hoop wind, or second fiber layer, fiber having a thickness of about 0.0005 to 0.001 inch and a wind density within the range of about 50 to 80 wraps per inch is generally adequate. The fiber of the second fiber layer is preferably continuous and is, for a standard-sized medical balloon, about 75-100 inches long.
[0023] The longitudinally placed fibers should be generally parallel to or substantially parallel to the long axis of the balloon or maximum longitudinal stability (non-stretch) of the balloon. The fibers of the hoop wind should be perpendicular to or substantially perpendicular to the fibers placed longitudinally for maximum radial stability (non-stretch) of the balloon. This distributes the force on the balloon surface equally and creates “pixels” of equal shape and size. In the case where the fibers of the hoop wind are at a small acute angle (e.g. about 10 degrees or more) to the longitudinal fibers, two hoop winds (in opposite direction) can be used for minimizing radial distention. FIG. 4 depicts a balloon having a second hoop wind 12 .
EXAMPLES
[0024] The following examples are provided to illustrate the practice of the present invention, and are intended neither to define nor to limit the scope of the invention in any manner.
Example 1
[0025] An angioplasty balloon, as shown in FIG. 1 , having a wall thickness of 0.0008 inch is inflated to about 100 psi, and the two open ends of the balloon are closed off. The inflation pressure maintains the shape (geometry) of the balloon in an inflated profile during the construction of the composite balloon. The balloon is a blow-molded balloon of highly oriented polyethylene terephthalate (PET). To the inflated balloon is applied a very thin coat of 3M-75 adhesive to hold the fibers sufficiently to prevent them from slipping out of position after placement on the balloon.
[0026] Kevlar® fibers are placed, by hand, along the length of the balloon as shown in FIG. 2 to provide the primary wind. Each of the fibers is substantially equal in length to the length of the long axis of the balloon. Twenty-four fibers are used, substantially equally spaced from each other. The fiber used for the primary wind has a thickness of 0.0006 inch.
[0027] Next, a hoop wind of Kevlar® fiber is applied radially around the circumference of and over substantially the entire length of the long axis of the balloon, as shown in FIG. 3 . The fiber has a thickness of 0.0006 inch and is applied at a wind density of 60 wraps per inch.
[0028] The fiber-wound based PET balloon is then coated with a 10% solution of Texin® 5265 polyurethane in dimethylacetamide (DMA) and allowed to cure at room temperature. Five additional coating of the polurethane solution are applied in about 6-hour increments, after which the pressure in the balloon is released. The resulting composite fiber-reinforced balloon is non-compliant and exhibits superior burst strength and abrasion and puncture resistance.
[0029] 3M-75 is a tacky adhesive available from 3M Company, Minneapolis, Minn. Kevlar® is a high strength, inelastic fiber available from the DuPont Company, Wilmington, Del. Texin® 5265 is a polyurethane polymer available from Miles, Inc., Pittsburgh, Pa.
Example 2
[0030] The procedure of Example 1 was repeated with the exception that Vectran® fiber, having a thickness of 0.0005 inch is used in place of the Kevlar® fiber. The resulting composite balloon is axially and radially non-compliant at very high working pressures. The balloon has a very high tensile strength and abrasion and puncture resistance.
[0031] Vectran® is a high strength fiber available from Hoechst-Celanese, Charlotte, N.C.
Example 3
[0032] A mandrel in the shape of a balloon as shown in FIG. 1 is made of a water-soluble wax. The wax mandrel is coated with a very thin layer (0.0002 inch) of Texin® 5265 polyurethane. After curing, adhesive and Vectran® fibers are applied, following the procedure of Example 1. Next, several coats of Texin® 5265 polyurethane as applied in Example 1. The wax is then exhausted by dissolving in hot water to give a non-compliant, very high strength, abrasion-resistant, composite fiber-reinforced balloon.
Example 4
[0033] The procedure of Example 3 is repeated using high strength Spectra® fiber in place of Vectran® fiber. Spectra® fiber is available from Allied Signal, Inc., Morristown, N.J.
Example 5
[0034] The procedure of Example 1 is repeated using Ultra High Molecular Weight Polyethylene (Spectra 2000) fiber, which has been flattened on a roll mill. To the flattened fiber is applied a thin coat of a solution of 1-MP Tecoflex® adhesive in a 60-40 solution of methylene chloride and methylethylketone. The fiber is applied to the balloon as in Example 1 using 30 longitudinal fibers, each substantially equal in length to the length of the long axis of the balloon, and a hoop wind of 54 wraps per inch. The fibers are then coated with the Tecoflex® solution.
[0035] Tecoflex® is supplied by Thermedics, Inc., Woburn, Mass.
Example 6
[0036] A balloon-shaped solid mandrel made of a low melting temperature metal alloy is coated with a thin layer of Texin® 5265/DMA solution (10%). Vectran® fibers are applied as in Example 1, followed by coating with Texin®/DMA. The metal mandrel is melted out using hot water. A very high strength, abrasion-resistant, composite balloon is obtained, which is non-compliant.
Example 7
[0037] Following the procedures of Example 6, a mandrel is coated with a very thin layer of PIM polyimide (2,2-dimethylbenzidine) in solution in cyclopentanone. Polyimide fibers are applied, and the composite balloon is then completed with additional applications of the PIM solution. The mandrel is removed to give a high strength, puncture-resistant balloon having an extremely cohesive fiber/matrix composite wall that is resistant to delamination.
Example 8
[0038] A balloon is constructed as in Example 7, except that the longitudinal fibers are replaced by a longitudinally oriented thin film made of polyimide LARC-1A film (available from IMITEC, Schenectady, N.Y.). The film is cut into a mandrel-shaped pattern and applied to the mandrel, over which the polyimide hoop fibers and the PIM solution are applied.
[0039] Although the illustrative embodiment has been described in detail, it should be understood that various changes, substitutions and alterations can be made therein without departing from the spirit and scope of the invention as defined by the appended claims.
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A non-compliant medical balloon, where the non-compliant medical balloon may be changed from a deflated state to an inflated state by increasing pressure within the balloon, is made with a first fiber layer, a second fiber layer over said first fiber layer such that the fibers of the first fiber layer and the fibers of the second fiber layer form an angle and a binding layer coating the first fiber layer and said second fiber layer. The interior surface area of the non-compliant medical balloon remains unchanged when the balloon changes from a deflated state to an inflated state.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional Application No. 61/895479, filed Oct. 25, 2013, which is hereby incorporated by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
PARTIES TO A JOINT RESEARCH AGREEMENT
[0003] Not Applicable
REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX
[0004] Not Applicable
BACKGROUND OF THE INVENTION
[0005] The invention relates generally to business cards and methods of generating interest and Internet traffic using business cards, and in particular to business cards that may be folded into secondary. Golf tees made out of paper and other lightweight foldable material are known in the prior art for their ability to be easily carried and distributed as a promotional item, and for the ability of paper items to degrade in a relatively short time if left discarded in an outdoor area such as a golf course. Such items generally fold or bend to provide a rise in one of two ways: a first type may provide multiple folds in a first dimension so that the full length of the item in a second dimension provides the rise to a rest point for the golf ball on top of one of the folded edges, and a second type provides a circular hole from which a perforated circular cutout suitable for use as a golf ball marker may be removed, and the edge of the empty hole becomes the rest point for the golf ball at a rise that is less than the full length of the second dimension of the item. The prior art lacks, however, a paper golf tee that provides the user with the option of two levels of rise at which to tee up the golf ball without having to disassemble and re-assemble the tee to achieve a different level. The prior art further does not disclose business methods related to paper golf tee products that aid in maximizing the promotional value such products, and how they relate to marketing and promotion in the modern digital age. The relationship of the paper golf tee to online promotion is of particular importance in light of the fact that paper golf tee products are likely to be wholly or partially destroyed or discarded when used as a tee.
[0006] Of the prior art, U.S. Design Pat. No. D651265 to Guerrero title “Paper Golf Tee” discloses a paper golf tee foldable from a rectangular card having perforations and creases as well as a circular cutout region. The cuts and creases of Guerrero, however, are suitable only for teeing the golf ball in the first of two positions described above, namely, the rise being equal to one of the paper item's dimensions. The assembled tee cannot be stably positioned so that the circular cutout region faces upward, and thus the circular cutout region cannot be used as a secondary ball support. Further, Guerrero lacks any interlocking structures—only a flap retainer—to maintain its assembled configuration. Further, Guerrero establishes a triangular structure in contact with the ground and only a single additional line of support outside of the triangular structure, which leads to a likelihood that the tee of Guerrero will be knocked over prematurely.
[0007] Further, U.S. Pat. No. 5,503,396 to Veylupek Jr. et al discloses a golf tee business card having a tab and slot system whereby a ball support point is created in the face of the card by the removal of the tab, and wherein the tab inserts and retains itself within one or more slots thereby causing the card to bend to create a rise. By selecting from among the several slots, the user may select the desire degree of rise. However, the Veylupek Jr. tee card suffers from the disadvantage that the degree of rise, once set, cannot be changed except by pulling the tab out of its interlocking slot. This procedure is fiddly and time consuming, and likely to damage the tab and/or the slot by the extra manipulation of the paper, thereby ruining its ability to function as a tee at all. Veylupek Jr. also does not disclose a removable marker disc and does not disclose any business methods related to the marketing use of the business card tee.
SUMMARY OF THE INVENTION
[0008] Accordingly, the invention is directed to a golf tee business card and methods of use as both a golf tee and as a business promotional item. A rectangular card is scored to create a perforated removable central disc and is creased vertically twice such that each crease intersects with the horizontally outermost points of the central disc. The card is further scored with two vertical cuts positioned equidistantly from the horizontal center and distally relative to the creases. Each vertical cut extends from the vertical center line to a tear point a short distance from the top or bottom edge such that one cut extends toward the top and the other cut extends toward the bottom.
[0009] The printed indicia of the card may include multiple forms of Internet location information, specifically to websites and social media outlets such that the card's information content may be easily retained by the recipient. Multiple locators are provided so that at least one Internet location or data identifier is likely to survive the use and possible destruction of the card as a golf tee.
[0010] The card may be torn at each tear point, folded along the creases and positioned so that the cuts interlock. The assembled configuration may be stood up on its side to tee up the ball in a first position suitable for use with a driver as when starting a par 4 or 5 hole. Alternatively, the assembled configuration may be placed with the disc cutout face up to tee up the ball in a second position suitable for use with a club other than a drive as when starting a par 3 hole.
[0011] Additional features and advantages of the invention will be set forth in the description which follows, and will be apparent from the description, or may be learned by practice of the invention. The foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings are included to provide a further understanding of the invention and are incorporated into and constitute a part of the specification. They illustrate one embodiment of the invention and, together with the description, serve to explain the principles of the invention.
[0013] FIG. 1 shows the front face template of the first exemplary embodiment, displaying the template region 10 , no-type region 11 , content region 12 , cutout edge 13 , content region edge 14 , perforated disc 15 , right crease 16 , left crease 17 , right cut 18 , left cut 19 , right tear point 20 , left tear point 21 , first horizontal guideline 22 a, second horizontal guideline 22 B, third horizontal guideline 22 C, fourth horizontal guideline 22 D, fifth horizontal guideline 22 E, sixth horizontal guideline 22 F, first vertical guideline 23 A, second vertical guideline 23 B, third vertical guideline 23 C, fourth vertical guideline 23 D, fifth vertical guideline 23 E, sixth vertical guideline 23 F, seventh vertical guideline 23 G, and eighth vertical guideline 23 H.
[0014] FIG. 2 shows the rear face template of the first exemplary embodiment, displaying the template region 10 , no-type region 11 , content region 12 , cutout edge 13 , content region edge 14 , perforated disc 15 , right crease 16 , left crease 17 , right cut 18 , left cut 19 , right tear point 20 , left tear point 21 , first horizontal guideline 22 a, second horizontal guideline 22 B, third horizontal guideline 22 C, fourth horizontal guideline 22 D, fifth horizontal guideline 22 E, sixth horizontal guideline 22 F, first vertical guideline 23 A, second vertical guideline 23 B, third vertical guideline 23 C, fourth vertical guideline 23 D, fifth vertical guideline 23 E, sixth vertical guideline 23 F, seventh vertical guideline 23 G, and eighth vertical guideline 23 H.
[0015] FIG. 3 shows one face of an exemplary embodiment of the invention bearing business indicia, displaying the heading 30 , Twitter identity 31 , Facebook identity 32 , 2-dimensional barcode 33 , URL 34 , and general promotional content 35 .
[0016] FIG. 4 shows a perspective view of the first exemplary embodiment in its first golf tee configuration, displaying the cutout edge 13 , right crease 16 , left crease 17 , right cut 18 , left cut 19 , and first ball support region 40 .
[0017] FIG. 5 shows a perspective view of the first exemplary embodiment in its second golf tee configuration with the perforated disc removed, displaying the cutout edge 13 , perforated disc 15 , right crease 16 , left crease 17 , right cut 18 , left cut 19 , and second ball support region 50 .
[0018] FIG. 6 shows a perspective view of the first exemplary embodiment in its third golf tee configuration with the perforated disc removed, displaying the right crease 16 , left crease 17 , and second ball support region 50 .
DETAILED DESCRIPTION OF THE INVENTION
[0019] Referring now to the invention in more detail, the invention is directed to a golf tee business card and methods of use as both a golf tee and as a business promotional item. FIGS. 1-2 show a print template for the card; the template region 10 is preferably 3¾ inches by 2¼ inches surrounding a finished card region preferably 3½ inches by 2 inches. The template is presented such that the front is shown in FIG. 1 , and the back, with the card flipped horizontally, is shown in FIG. 2 . The preferred sizes are intended to match with common practice for business card sizes in the United States, though cards in other customary sizes or non-customary sizes as well as non-rectangular shapes are also contemplated. In addition to a business card embodiment, the invention may be embedded in other types of cards bearing different customary indicia, such as gift cards or certificates, greeting cards, golf scorecards, golf yardage guides or books, and garment tags (for example tags of garments sold in a golf course shop).
[0020] The card itself is preferable made of a heavy cardstock material, optionally with an aqueous coating and/or a UV coating, though other durable paper and plastic materials are known in the art of business card printing, and any lightweight and low cost foldable, creaseable, and scoreable sheet material may be used. Materials that will quickly degrade in outdoor conditions, as when the card or fragments thereof are discarded on a golf course, are preferred.
[0021] The templates of FIGS. 1-2 show a series of guidelines 22 and 23 indicating the preferred positioning of features on the card. The guidelines are preferably not printed on the card, but may be provided with a digital file template of the card. All measurements of the guidelines 22 and 23 are relative to the front face of the uncut template region 10 . Within the template region 10 is the cutout edge 13 , and within the cutout edge 13 is the content region edge, all preferably concentric rectangles. The first horizontal guideline 22 A is preferably ⅛ inches from the top edge of the template region 10 and defines the top of the cutout edge 13 . The second horizontal guideline 22 B is preferably ¼ inches from the top edge of the template region 10 and defines the top of the content region edge 14 . The third horizontal guideline 22 C is preferably 25/32 inches from the top edge of the template region 10 and defines the top extreme point of the perforated disc 15 (the perforated disc being understood, while in digital form, as a region of the template). The fourth horizontal guideline 22 D is preferably 25/32 inches from the bottom edge of the template region 10 and defines the bottom extreme point of the perforated disc 15 . The fifth horizontal guideline 22 E is preferably located ¼ inches from the bottom of the template region 10 and defines the bottom of the content region edge 14 . The sixth horizontal guideline 22 F is preferably ⅛ inches from the bottom edge of the template region 10 and defines the bottom of the cutout edge 13 .
[0022] The first vertical guideline 23 A is preferably ⅛ inches from the left edge of the template region 10 and defines the left side of the cutout edge 13 . The second vertical guideline 23 B is preferably ¼ inches from the left edge of the template region 10 and defines the left side of the content region edge 14 . The third vertical guideline 23 C is preferably positioned 19/32 inches from the left edge of the template region 10 and defines the line of the left cut 19 . The fourth vertical guideline 23 D is preferably 1 17/32 inches from the left edge of the template region 10 and defines the left extreme point of the perforated disc 15 . The fifth horizontal guideline 23 E is preferably 1 17/32 inches from the right edge of the template region 10 and defines the right extreme point of the perforated disc 15 . The sixth vertical guideline 23 F is preferably positioned 19/32 inches from the right edge of the template region 10 and defines the line of the right cut 18. The seventh vertical guideline 23G is preferably ¼ inches from the right edge of the template region 10 and defines the right side of the content region edge 14 . The eighth vertical guideline 23 H is preferably ⅛ inches from the right edge of the template region 10 and defines the right side of the cutout edge 13 .
[0023] The template region 10 encompasses the finished card area bounded by guidelines 22 A, 23 H, 22 F, and 23 A, which define the cutout edge 13 . In its preferred size, the cutout edge 13 leaves a surrounding waste region ⅛ inches wide. The cutout edge 13 surrounds a no-type region 11 , which is intended to be a part of the finished card, but is not intended to receive any informational printing, thus allowing for some variance in the precise cutting of the finished card from the template region 10 . In its intended size, the no-type region 11 is ⅛ inches wide. The no-type region 11 surrounds the content region 12 , with the boundary between the two defined by the content region edge 14 . The content region edge 14 is preferably not a printed line on the finished card. The content region edge 14 is defined by guidelines 22 B, 23 G, 22 E, and 23 B.
[0024] A perforated disc 15 is preferably centered on the card both horizontally and vertically. The perforated disc 15 is scored so that it may be punched out by hand by the user. The perforated disc 15 in its preferred shape and size is circular with a diameter of 11/16 inches. The perforated disc 15 has four cardinal extreme points, each intersecting one of the guidelines 22 C, 23 E, 22 D, and 23 D.
[0025] A left crease 17 and a right crease 16 are provided in the vertical dimension, thus permitting the card to be easily folded. The left crease 17 aligns with the fourth vertical guideline 23 D, and the right crease 16 aligns with the fifth vertical guideline 23 E. Both the left crease 17 and the right crease 16 extend over the whole vertical length of the finished card.
[0026] A left cut 19 and a right cut 18 are provided. The left cut 19 aligns with the third vertical guideline 23 C. The right cut 18 aligns with the sixth vertical guideline 23 F. The left cut 19 extends from the vertical center of the card (equivalently, of the template region 10 or of the content region 12 ) to the left tear point 21 , which is preferably located 1/16 inches above the cutout edge 13 on the third vertical guideline 23 C. The right cut 18 extends from the vertical center of the card to the right tear point 20 , which is preferably located 1/16 inches below the cutout edge 13 on the sixth vertical guideline 23 F.
[0027] The dimensions shown in the template are intended to be exemplary only, and may vary with the particular application of each embodiment and the particular printing and scoring techniques used.
[0028] To use the invention in the game of golf, the user may optionally first remove the perforated disc 15 and use it as a ball marker. The user then prepares a tee by tearing both the left tear point 21 and the right tear point 20 , which causes the left cut 19 and the right cut 18 to become slots that extend to the edge of the card in opposing directions. The user then folds the card over the left crease 16 and the right crease 17 , and then interlocks the left cut 19 and the right cut 20 as shown in FIG. 4 . FIG. 4 shows the card as folded with the front face directed outward, however the user may obtain equivalent results by folding the card inversely with the back face directed outward. The card thus configured may be supported on its bottom or top edge with the opposing edge defining a first ball support region 40 . With the perforated disc 15 removed, the card thus configured may be supported on its left and right edges as shown in FIG. 5 . The hole left by the removed perforated disc 15 becomes a second ball support region 50 .
[0029] Using the preferred sizes, the first ball support region 40 is higher than the second ball support region 50 . The first ball support region 40 is thus preferred when using a driver as on a par 4 or 5 hole, and the second ball support region 50 is thus preferred when using a club other than a driver, as on a par 3 hole. An additional third ball support configuration is shown in FIG. 6 , wherein the left cut 19 and right cut are de-interlocked such that the card may stand on its folded leaves with the second ball support region directed vertically upward.
[0030] FIG. 3 shows the significant informational content of an exemplary embodiment of the invention. Specifically, the card's informational content preferably includes multiple means of obtaining digital promotional information or locating the card's distributor on the Internet. In addition to a heading 30 and general promotional content 35 (including such traditional information as the business name, address, telephone and fax numbers, etc.), the card provides a Twitter identity 31 , Facebook identity 32 , a 2-dimensional barcode 33 , and a URL 34 . The Twitter identity 31 and Facebook identity 32 are exemplary social media identities; other social media systems with their own identifiers may be used to complement the social media presence of the provider of the card. The 2-dimensional barcode 33 preferably contains a digitally encoded URL or social media link, or a VCard or other promotional data. Preferably, at least one data identifier or Internet location is positioned on the separable perforated disc 15 , as the 2-dimensional barcode 33 is positioned as shown. The presence of multiple locators and the presence of at least one locator on the perforated disc 15 increases the likelihood that at least some promotional material will survive when the card is actually used in the game of golf.
[0031] To use the invention as a promotional tool, the promotional user first selects the marketing message, Internet location information, and other information content of the card and incorporates the information into a graphic design for both the front and back of the card, being mindful to place specially separable information on the perforated disc 15 . In addition to an internet locator, the specially separable information may include a graphic logo with which the user may signal an affiliation or affinity while using the perforated disc 15 as a ball marker token. The promotional user then brings copies of the cards to a face-to-face encounter where the promotional user will make new contacts and distributes the cards to the new contacts. In each conversation, the promotional user may bring up the card's features as a golf tee and ball marker, using a verbal description of its use and optional demonstration as an ice-breaker. The conversation will thus improve the chances that the new contact will both form a lasting memory of the promotional user and will follow up by visiting the promotional user's websites or social media outlets. Also increased is the likelihood that the recipient of the card will, when reviewing recently obtained promotional material, recall the explanation and/or demonstration of the card's use in the game of golf and, by extension the promotional user, thus reinforcing the recalled memory.
[0032] Components, component sizes, and materials listed above are preferable, but artisans will recognize that alternate components and materials could be selected without altering the scope of the invention.
[0033] While the foregoing written description of the invention enables one of ordinary skill to make and use what is presently considered to be the best mode thereof, those of ordinary skill in the art will understand and appreciate the existence of variations, combinations, and equivalents of the specific embodiment, method, and examples herein. The invention should, therefore, not be limited by the above described embodiment, method, and examples, but by all embodiments and methods within the scope and spirit of the invention.
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A golf tee business card and methods of use as both a golf tee and as a business promotional item are disclosed. A rectangular card is scored to create a removable disc and is creased vertically twice such that each crease intersects with the horizontally outermost points of the disc. The card is further scored with two vertical cuts; each vertical cut extends from the vertical center line to a tear point a short distance from the top or bottom edge. The card's information content may include multiple forms of Internet location information. The card may be torn at each tear point, folded along the creases and positioned so that the cuts interlock. The assembled configuration may be stood up on its side to tee up the ball or may be placed with the disc cutout face up to tee up the ball.
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RELATED APPLICATIONS
[0001] This is a Continuation of U.S. patent application Ser. No. 14/939,025 filed Nov. 12, 2015, now U.S. Pat. No. 9,580,315, which is a Divisional of U.S. patent application Ser. No. 14/347,431 filed Mar. 26, 2014, now U.S. Pat. No. 9,499,404, which is a 371 US National Phase of PCT/US2012/057594 filed Sep. 27, 2012, which, in turn, claims priority to U.S. Provisional Patent Application No. 61/539,924 filed Sep. 27, 2011. The contents of the aforementioned applications are incorporated by reference in their entirety.
FIELD OF THE INVENTION
[0002] The present invention is directed to the processing of syngas created from the processing of carbonaceous material.
BACKGROUND
[0003] A raw synthesis gas product, hereinafter called ‘unconditioned syngas’, is generated by the process of steam reforming, and may be characterized by a dirty mixture of gases and solids, comprised of carbon monoxide, hydrogen, carbon dioxide, methane, ethylene, ethane, acetylene, and a mixture of unreacted carbon and ash, commonly called ‘char’, as well as elutriated bed material particulates, and other trace contaminants, including but not limited to ammonia, hydrogen chloride, hydrogen cyanide, hydrogen sulfide, carbonyl sulfide, and trace metals. FIG. 28 presents a more complete list of components that may be found in unconditioned syngas.
[0004] Unconditioned syngas may also contain a variety of volatile organic compounds (VOC) or aromatics including benzene, toluene, phenol, styrene, xylene, and cresol, as well as semi-volatile organic compounds (SVOC) or polyaromatics, such as indene, indan, napthalene, methylnapthalene, acenapthylene, acenapthalene, anthracene, phenanthrene, (methyl-)anthracenes/phenanthrenes, pyrene/fluoranthene, methylpyrenes/benzofluorenes, chrysene, benz[a]anthracene, methylchrysenes, methylbenz[a]anthracenes, perylene, benzo[a]pyrene, dibenz[a,kl]anthracene, and dibenz[a,h]anthracene.
[0005] Syngas processing technology applications can generally be defined as industrial processing systems that accept a syngas source and produce or synthesize something from it. Normally, these can be categorized into systems that generate hydrogen, ethanol, mixed alcohols, methanol, dimethyl ether, chemicals or chemical intermediates (plastics, solvents, adhesives, fatty acids, acetic acid, carbon black, olefins, oxochemicals, ammonia, etc.), Fischer-Tropsch products (LPG, Naptha, Kerosene/diesel, lubricants, waxes), synthetic natural gas, or power (heat or electricity).
[0006] A plethora of syngas processing technologies exist, each converting syngas into something, and each possessing its own unique synthesis gas cleanliness requirement. For example, a Fischer-Tropsch (FT) catalytic synthesis processing technology requires more stringent cleanliness requirements when compared to a methanol synthesis application. This is because some FT cobalt catalysts are extremely sensitive to sulfur, resulting in deactivation, whereas sulfur does not pose a problem for some catalytic methanol applications. Therefore, a vast array of permutations or combinations of syngas clean-up operational sequence steps are possible to meet the economical and process intensive demands of synthesis gas conversion technologies.
SUMMARY OF THE INVENTION
[0007] In one aspect, the present invention is directed to a method of processing unconditioned syngas. The method comprises removing solids and semi-volatile organic compounds (SVOC) from the unconditioned syngas, then removing volatile organic compounds (VOC), and then removing at least one sulfur containing compound.
[0008] In another aspect, the present invention is directed to a system for processing unconditioned syngas. The system comprises means for removing solids and semi-volatile organic compounds (SVOC) from the unconditioned syngas, a compressor configured to receive and compress the resultant syngas stream, means for removing volatile organic compounds (VOC) from the compressed resultant syngas stream, and at least one bed configured to receive VOC-depleted syngas stream and remove at least one sulfur compound.
[0009] In yet another aspect, the present invention is directed to a method for removing solids and semi-volatile organic compounds (SVOC) from unconditioned syngas. The method includes (a) contacting the unconditioned syngas with a solvent and water to thereby form an intermediate SVOC-depleted syngas containing steam, and a first mixture comprising SVOC, solids, solvent and water; (b) removing steam from the intermediate SVOC-depleted syngas containing steam to form: (i) a first depleted syngas stream which has a reduced amount of SVOC relative to the unconditioned gas stream, and (ii) a second mixture comprising SVOC, solids, solvent and water; (c) separating the water within the second mixture based upon immiscibility so that the SVOC, solids and solvent collect together to form a third mixture above the water; (d) separating the solids from the SVOC and solvent in a vessel having at least one liquid phase candle filter such that the solids agglomerate on a surface of the candle filter and form a filter cake having density greater than that of water within the vessel; (e) backflushing the candle filter to loosen the filter cake so that the filter cake sinks into the water within the vessel; and (f) removing the filter cake from a bottom of the vessel.
[0010] In still another aspect, the present invention is directed to a system for removing solids and semi-volatile organic compounds (SVOC) from unconditioned syngas. The system includes: a venturi scrubber configured to receive the unconditioned syngas, solvent and water and output an intermediate SVOC-depleted syngas containing steam together with a first mixture comprising SVOC, solids, solvent and water; a char scrubber configured to receive the intermediate SVOC-depleted syngas containing steam and the first mixture, and separately output: (i) a first depleted syngas stream which has a reduced amount of SVOC relative to the unconditioned gas stream, and (ii) a second mixture comprising SVOC, solids, solvent and water; a decanter configured to receive the second mixture and separate the water within the second mixture based upon immiscibility so that the SVOC, solids and solvent collect together to form a third mixture above the water within the decanter, the decanter further configured to separately output the water and the third mixture; and a vessel arranged to receive the third mixture, the vessel having at least one liquid phase candle filter and a vessel bottom provided with a drain port; wherein: the candle filter is capable of operating so that: (i) the solids agglomerate on a surface of the candle filter and form a filter cake, and (ii) the SVOC and solvent are removed through the candle filter, and the drain port is suitable for removing filter cake therethrough.
[0011] The present invention is further directed to a system for processing unconditioned syngas which include the aforementioned system for removing solids and semi-volatile organic compounds (SVOC), in combination with various types of VOC-removal equipment and sulfur-removal equipment which operate under pressure.
[0012] These and other aspects of the present invention are described below in further detail.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 —Syngas Clean-Up Step Flow Diagram
[0014] FIG. 1A-1D —Syngas Clean-Up System
[0015] FIGS. 1E-1F —Abbreviated Syngas Clean Up System and Process
[0016] FIG. 2 —Step B, Hydrocarbon Reforming Module
[0017] FIG. 3 —Step C, Syngas Cooling Module
[0018] FIG. 4 —Step D, Option 1 , Block Process Flow Diagram for Solids & SVOC Removal
[0019] FIG. 5 —Step D, Solids & SVOC Removal Module
[0020] FIG. 6 —Step D, Option 1 , Continuous Solvent Filtration & Filtrate Backflush Regeneration Module
[0021] FIG. 7 —Filtrate Backflush Regeneration Operation Process Flow Diagram
[0022] FIG. 8 —Step D, Option 1 , Sequence Step Operation Flow Diagram
[0023] FIG. 9 —Step D, Option 2 , Block Process Flow Diagram for Solids & SVOC Removal
[0024] FIG. 10 —Step D, Option 2 , Sequence Step Operation Process Flow Diagram
[0025] FIG. 11 —SVOC Separation System, Option 1 , SVOC Flash Separation Module
[0026] FIG. 12 —SVOC Separation System, Option 2 , SVOC Sorptive Separation Module
[0027] FIG. 13 —Step E, Chlorine Removal Module
[0028] FIG. 14 —Step F, Sulfur Removal Module
[0029] FIG. 15 —Step G, Particulate Filtration Module
[0030] FIG. 16 —Step H, Syngas Compression Module
[0031] FIG. 17 —Step I, VOC Removal Module
[0032] FIG. 18 —Step I, VOC Separation System, Option 1 , TSA/PSA System
[0033] FIG. 19 —Step I, VOC Separation System, Option 2 , Fluidized Bed Adsorber System
[0034] FIG. 20 —Step J, Metal Removal Module
[0035] FIG. 21 —Step K, Ammonia Removal Module
[0036] FIG. 22 —Step L, Ammonia Polishing Module
[0037] FIG. 23 —Step M, Heat Addition Module
[0038] FIG. 24 —Step N, Carbonyl Sulfide Removal Module
[0039] FIG. 25 —Step O, Sulfur Polishing Module
[0040] FIG. 26 —Step P, Carbon Dioxide Removal Module
[0041] FIG. 27 —Steps Q, R, & S Heat Integration & Hydrocarbon Reforming Module
[0042] FIG. 28 —Typical Components within Unconditioned Syngas
[0043] FIG. 29 —Sequence Step Parameter & Contaminant Removal Efficiency
[0044] FIGS. 30A-30F —List of Combinations of Steps Associated With Various Syngas Clean-Up Methods
DETAILED DESCRIPTION
[0045] FIG. 1 lists each syngas clean-up operational sequence step that may be included in an overall syngas cleaning process. As discussed below, not all steps need be performed in every implementation and so one or more of the steps may be optional.
[0046] The focus of the following text is to describe in detail the functionality, flexibility, and variability of each syngas clean-up process operational sequence step in communication with one another. It is further an object of the following text to elaborate upon the varying permutations of syngas clean-up process operational sequence steps to form an integrated syngas clean-up process.
[0047] Selection of a precise combination and/or permutation of steps and equipment may be important, as dictated by various criteria. Depending upon the process conditions involved, albeit be chemical and reactionary in nature, temperature, pressure, or presence or absence of a specific contaminate or component species, (such as water, for example) certain logical requirements and practical proprietary heuristics dictate where in the entire permutable sequence of unit operations a specific syngas clean-up operational sequence step may be placed.
[0048] A multitude of permutations of syngas operational sequence steps are possible to realize an overall integrated syngas clean-up process. Syngas contaminant tolerances, or cleanliness requirements of downstream syngas processing technologies, dictate how elaborate a given integrated syngas clean-up process must be.
[0049] The idea of a control volume is an extremely general concept used widely in the study and practice of chemical engineering. Control volumes may be used in applications that analyze physical systems by utilization of the laws of conservation of mass and energy. They may be employed during the analysis of input and output data of an arbitrary space, or region, usually being a chemical process, or a portion of a chemical process. They may be used to define process streams entering a single piece of chemical equipment that performs a certain task, or they may be used to define process streams entering a collection of equipment, and assets which work together to perform a certain task.
[0050] With respect to the surrounding text, a control volume is meaningful in terms of defining the boundaries of a particular syngas clean-up sequence step. With respect to the accompanied text, a sequence step may be defined as a member of an ordered list of events. These events may be arranged in a plethora of varying ways depending upon any number of requirements dictated by contaminant tolerances of any type of sygnas processing technology. Each sequence step is assigned a name corresponding to the problem is solves.
[0051] The arrangements of equipment contained within each control volume are the preferred ways of accomplishing each sequence step. Furthermore, all preferred embodiments are non-limiting in that any number of combinations of unit operations, equipment and assets, including pumping, piping, and instrumentation, may be used as an alternate. However, it has been our realization that the preferred embodiments that make up each sequence step are those which work best to realize contaminant removal efficiencies as described in FIG. 29 . Nonetheless, any types of unit operations or processes may be used within any control volume shown as long as it accomplishes the goal of that particular sequence step.
[0052] FIGS. 1A through 1D depict one embodiment of a system consistent with the steps shown in FIG. 1 to realize an overall integrated syngas clean-up process. The specific details of each control volume are elaborated upon in the accompanied text below.
[0053] FIG. 1A illustrates a Hydrocarbon Reforming Control Volume [B- 1 ] accepting an unconditioned syngas through a Sequence Step B Syngas Inlet [B-IN] and outputting a syngas of improved quality through a Sequence Step B Syngas Discharge [B-OUT]. Syngas quality improvement is defined below and is achieved through hydrocarbon reforming and/or cracking with the use of either partial oxidative, catalytic, or non-thermal non-catalytic systems or processes.
[0054] Syngas of improved quality is then routed to a Syngas Cooling Control Volume [C- 1 ] through a Sequence Step C Syngas Inlet [C-IN] which reduces the temperature of the syngas prior to outputting the cooled syngas through a Sequence Step C Syngas Discharge [C-OUT]. Any number of processes and unit operations may be employed to cool the syngas within this control volume and the objective of this process step is to reduce the temperature of the syngas prior to the removal of solids and semi-volatile organic compounds (SVOC) within the following sequence step.
[0055] Solids and SVOC are next removed from the unconditioned syngas within a Solids Removal & SVOC Removal Control Volume [D- 1 ]. A solids and SVOC laden Sequence Step D Syngas Inlet [D-IN] is provided to the control volume where the assets included therein remove solids and SVOC from the syngas to output a solids and SVOC-depleted Sequence Step D Syngas Discharge [D-OUT]. It is preferable to remove solids and SVOC utilizing the systems and methods as described below, however any type of systems and methods may be utilized within this control volume to accomplish the goal of the sequence step to remove solids and SVOC from syngas.
[0056] FIG. 1B illustrates the solids and SVOC-depleted Sequence Step D Syngas Discharge [D-OUT] being routed to a Chlorine Removal Control Volume [E- 1 ] which accepts through a chlorine laden Sequence Step E Syngas Inlet [E-IN] and outputs a chlorine depleted Sequence Step E Syngas Discharge [E-OUT]. It is preferable that chlorine is scrubbed from the syngas with the use of water, however any type of scrubbing liquid may be used, and in addition, any type of chlorine removal process or system may be employed to accomplish the goal of the sequence step to remove chlorine from syngas.
[0057] Syngas depleted of chlorine is then routed to a Sulfur Removal Control Volume [F- 1 ] which accepts as a sulfur laden Sequence Step F Syngas Inlet [F-IN], and outputs a sulfur-depleted Sequence Step F Syngas Discharge [F-OUT]. It is preferable that sulfur is scrubbed from the syngas with the use of a triazine hydrogen sulfide scavenger, however any type of scrubbing liquid may be used, and in addition, any type of sulfur removal process or system may be employed to accomplish the goal of the sequence step to remove sulfur from syngas.
[0058] Syngas depleted of sulfur is then routed to a Particulate Filtration Control Volume [G- 1 ] which accepts as a particulate laden Sequence Step G Syngas Inlet [G-IN], and outputting a particulate depleted Sequence Step G Syngas Discharge [G-OUT]. It is desirable to have this sequence step in place immediately prior to the compression step so as to provide a final separation of any solids that may carry over, or become elutriated, during any intermittent operational upset within the upstream solids removal unit operations.
[0059] Syngas is then routed to a Syngas Compression [H] step wherein a Syngas Compressor accepts as a Sequence Step H Syngas Inlet [H-IN], and outputs a Sequence Step H Syngas Discharge [H-OUT]. The following described sequence steps and processes illustrated in FIGS. 1 C through 1 D primarily operate at a pressure higher than the preceding described sequence steps, relatively, since the compressor elevates the pressure of the syngas so that the outlet syngas is at a higher pressure in relation to the inlet syngas pressure.
[0060] As seen in FIG. 1C , compressed syngas is then routed to a Volatile Organic Compounds (VOC) Removal Control Volume [I- 1 ], which accepts as a VOC laden Sequence Step I Syngas Inlet [I-IN], and outputs a VOC-depleted Sequence Step I Syngas Discharge [I-OUT]. It is preferable that VOC is removed with the use of pressure swing and temperature swing adsorption and desorption methods and systems utilizing either microchannel heat exchangers, or pressure or temperature swing adsorption and desorption methods and systems utilizing fixed beds, or even utilizing fluidized bed systems and methods in which syngas fluidizes a sorbent material to remove VOC within the syngas, and in addition, any type of VOC removal process or system may be employed to accomplish the goal of the sequence step to remove VOC from syngas.
[0061] VOC-depleted syngas is the routed to a Metal Removal Control Volume [J- 1 ] which accepts through a metal laden Sequence Step J Syngas Inlet [J-IN], and outputs a metal depleted Sequence Step J Syngas Discharge [J-OUT]. It is preferable that metals are adsorbed from the syngas with the use fixed bed systems and methods utilizing suitable adsorbent materials, however absorption may employed instead, and in addition, any type of metals removal process or system may be employed to accomplish the goal of the sequence step to remove metal from syngas.
[0062] Syngas depleted of metals is then routed to an Ammonia Removal Control Volume [K- 1 ] which accepts as an ammonia laden Sequence Step K Syngas Inlet [K-IN], and outputs an ammonia-depleted Sequence Step K Syngas Discharge [K-OUT]. It is preferable that ammonia is scrubbed from the syngas with the use of water, however any type of scrubbing liquid may be used, and in addition any type of ammonia removal system may be employed to accomplish the goal of the sequence step to remove ammonia from syngas.
[0063] Syngas depleted of ammonia is then routed to an Ammonia Polishing Control Volume [L- 1 ] which accepts as a Sequence Step L Syngas Inlet [L-IN], and outputs Sequence Step L Syngas Discharge [L-OUT]. It is preferable that ammonia is polished from the syngas using fixed bed adsorption systems and methods; however any type of ammonia polishing system may be employed to accomplish the goal of the sequence step to polish ammonia from syngas.
[0064] FIG. 1D displays a series of sequence steps to be performed to remove sulfur containing compounds. Syngas polished of ammonia is routed to a Heat Addition Control Volume [M- 1 ], which accepts through a Sequence Step M Syngas Inlet [M-IN], and outputs a Sequence Step M Syngas Discharge [M-OUT]. The goal of this control volume is to elevate the temperature of the syngas prior to removal of sulfur containing compounds.
[0065] Syngas at an elevated temperature is then routed to a Carbonyl Sulfide Removal Control Volume [N- 1 ] which accepts a carbonyl sulfide laden Sequence Step N Syngas Inlet [N-IN], and outputs a sulfur-depleted Sequence Step N Syngas Discharge [N-OUT]. It is preferred to accomplish the goals of this sequence step with the utilization of a packed bed of an alumina based material which allows for the hydrolysis of carbonyl sulfide into carbon dioxide and hydrogen sulfide, however any type of carbonyl sulfide removal system or method, such as adsorption or absorption type systems, may be employed to accomplish the goal of the sequence step to remove carbonyl sulfide from syngas.
[0066] Sulfur-depleted syngas is then routed to a final Sulfur Polishing Control Volume [O- 1 ] which accepts as a Sequence Step O Syngas Inlet [O-IN], and outputs through a Sequence Step O Syngas Discharge [O-OUT]. It is preferable that sulfur is polished from the syngas using fixed bed adsorption systems and methods; however any type of sulfur polishing system may be employed to accomplish the goal of the sequence step to polish sulfur from syngas.
[0067] Sulfur-depleted syngas is then routed to a Carbon Dioxide Removal Control Volume [P- 1 ], which accepts through a carbon dioxide laden Sequence Step P Syngas Inlet [P-IN], and outputting a carbon dioxide depleted Sequence Step P Syngas Discharge [P-OUT]. Membrane based processes are the preferred system utilized to remove carbon dioxide from syngas, however other alternate systems and methods may be utilized to accomplish the goals of this sequence step, not limited to adsorption or absorption based carbon dioxide removal systems and processes. In a further embodiment, carbon dioxide may be reduced within this sequence step by use of a carbon dioxide electrolyzer.
[0068] FIG. 1E represents a preferred embodiment where an unconditioned syngas is provided to a Solids Removal & SVOC Removal Control Volume [D- 1 ] which accepts unconditioned syngas through a solids and SVOC laden Sequence Step D Syngas Inlet [D-IN] and removes solids and SVOC from the unconditioned syngas to form a first depleted syngas stream thereby discharging through a solids and SVOC-depleted Sequence Step D Syngas Discharge [D-OUT]. The first depleted syngas stream has a reduced amount of solids and SVOC relative to the unconditioned syngas.
[0069] The first depleted syngas stream is then routed to a Volatile Organic Compounds (VOC) Removal Control Volume [I- 1 ], which accepts as a VOC laden Sequence Step I Syngas Inlet [I-IN], and removes volatile organic compounds (VOC) from the first depleted syngas stream to form a second depleted syngas stream which has a reduced amount of VOC relative to the first depleted syngas stream thereby outputting through a VOC-depleted Sequence Step I Syngas Discharge [I-OUT].
[0070] The second depleted syngas stream is then routed to a Carbonyl Sulfide Removal Control Volume [N- 1 ] which accepts as a carbonyl sulfide laden Sequence Step N Syngas Inlet [N-IN], and removes at least one sulfur containing compound from the second depleted syngas stream to produce a sulfur-depleted syngas stream which has a reduced sulfur amount of sulfur relative to the second depleted syngas stream thereby outputting as a sulfur-depleted Sequence Step N Syngas Discharge [N-OUT].
[0071] The sulfur-depleted syngas stream is then routed to a final Sulfur Polishing Control Volume [O- 1 ] which accepts as a Sequence Step O Syngas Inlet [O-IN], and provides an additional sulfur polishing step to reduce total sulfur content to less than 100 part-per billion thereby discharging through a Sequence Step O Syngas Discharge [O-OUT].
[0072] FIG. 1F represents a preferred embodiment where an unconditioned syngas is provided to a Solids Removal & SVOC Removal Control Volume [D- 1 ] which accepts unconditioned syngas through a solids and SVOC laden Sequence Step D Syngas Inlet [D-IN] and removes solids and SVOC from the unconditioned syngas to form a first depleted syngas stream thereby discharging through a solids and SVOC-depleted Sequence Step D Syngas Discharge [D-OUT]. The first depleted syngas stream has a reduced amount of solids and SVOC relative to the unconditioned syngas.
[0073] The first depleted syngas stream is then routed to a Volatile Organic Compounds (VOC) Removal Control Volume [I- 1 ], which accepts as a VOC laden Sequence Step I Syngas Inlet [I-IN], and removes volatile organic compounds (VOC) from the first depleted syngas stream to form a second depleted syngas stream which has a reduced amount of VOC relative to the first depleted syngas stream thereby outputting through a VOC-depleted Sequence Step I Syngas Discharge [I-OUT].
[0074] The second depleted syngas stream is then routed to a final Sulfur Polishing Control Volume [O- 1 ] which accepts as a Sequence Step O Syngas Inlet [O-IN], and provides an additional sulfur polishing step to generate a sulfur-depleted syngas stream which has a reduced sulfur amount of sulfur relative to the second depleted syngas stream thereby discharging through a Sequence Step O Syngas Discharge [O-OUT].
Sequence Step B, Hydrocarbon Reforming [B]
[0075] FIG. 2 illustrates Sequence Step B, Hydrocarbon Reforming [B]. Hydrocarbon Reforming Control Volume [B- 1 ] encapsulates the preferred arrangement of equipment and assets that work together to provide a method for improving syngas quality by reforming and/or cracking one or more undesirable syngas constituents into desirable syngas constituents.
[0076] As used herein the term “desirable syngas constituents” or “favorable syngas constituents” or variants thereof refer to hydrogen (H 2 ) and carbon monoxide (CO).
[0077] As used herein the term “undesirable syngas constituents” refer to any constituents present in syngas other than hydrogen (H 2 ) and carbon monoxide (CO), including, but not limited to, carbon dioxide (CO 2 ), hydrocarbons, VOC, SVOC, nitrogen containing compounds, sulfur containing compounds, as well as other impurities that are present in the feedstock that can form during thermochemical syngas generation processes.
[0078] As used herein the term “hydrocarbon” refers to organic compounds of hydrogen and carbon, CxHy. These may include, but not limited to methane (CH 4 ), ethane (C 2 H 6 ), ethylene (C 2 H 4 ), propane (C 3 H 8 ), benzene (C 6 H 6 ), etc. Hydrocarbons include VOC and SVOC.
[0079] As used herein “improved syngas quality” or variants thereof refer to a syngas where at least one undesirable syngas constituent is reformed and/or cracked into at least one desirable syngas constituent.
[0080] As used herein the term “cracking” or “cracked” or variations thereof mean that undesirable syngas constituents, including hydrocarbons, SVOC, and/or VOC, are reacted with a suitable catalyst and/or in a partial oxidative environment and/or in a non-thermal non-catalytic plasma environment, to provide chemical species comprised of decreased molecular weights. For example, raw syngas that may contain propane (C 3 H 8 ), having a molecular weight of 44 lb/mol, may be cracked into compounds comprised of lesser molecular weights, for example, methane (CH 4 ) and ethylene (C 2 H 4 ), both having lesser molecular weights than that of propane, being 16 lb/mol and 28 lb/mol, respectively.
[0081] As used herein the term “reforming” or “reformation” or variations thereof mean that undesirable syngas constituents, including hydrocarbons, SVOC, and/or VOC, are converted into desirable syngas constituents. For example, in the presence of an oxidant and a suitable catalyst and/or in a partial oxidative environment and/or in a non-thermal non-catalytic plasma environment, methane (CH 4 ) can be reformed into carbon monoxide (CO) and hydrogen (H 2 ).
[0082] Unconditioned syngas may be transferred from a Syngas Generation [A] system, preferably a biomass steam reforming system (not shown), and routed through Sequence Step B Syngas Inlet [B-IN] into a Hydrocarbon Reforming Control Volume [B- 1 ], which produces a Sequence Step B Syngas Discharge [B-OUT].
[0083] This Hydrocarbon Reformer [ 8000 ] is preferably of a non-thermal, non-catalytic, cold plasma gliding-arc type, however, partial oxidation, and/or catalytic systems, or combinations thereof, may be employed to accomplish the sequence step objective of hydrocarbon reforming and/or cracking for syngas quality improvement. The Hydrocarbon Reformer generates a syngas or improved quality and depleted of VOC, SVOC, and other less desirable constituents, including, carbon dioxide, methane, ethylene, ethane, and acetylene, which may then be routed from the reformer through a Sequence Step B Syngas Discharge [B-OUT].
[0084] Additives [ 2 ], including solids possessing low ionization potential, not only including alkali metals, preferably sodium compounds or potassium compounds or mixtures thereof, may be provided to the Hydrocarbon Reformer. Utilization of these additives serves the purpose to increase the ionization energy in the cold plasma reaction zone within the Hydrocarbon Reformer, and thus aiding the decomposition of SVOC, and VOC, along with the less desirable syngas constituents, into favorable constituents including carbon monoxide and hydrogen. The presence of the additives within the Hydrocarbon Reformer favorably alters the electron density within the cold plasma arc reaction zone. This in turn enhances the thermochemical and electrochemical properties within the plasma reaction zone resultantly increasing the efficiency of the Hydrocarbon Reformer to reform and/or crack the VOC, SVOC, and other less desirable constituents into carbon monoxide and hydrogen.
[0085] An oxidant source [ 4 ], including, but not limited to, carbon dioxide, steam, air, or oxygen, may be made available to the Hydrocarbon Reformer to increase the reforming and/or cracking efficiency to promote production of carbon monoxide and hydrogen.
[0086] A gaseous hydrocarbon source [ 6 ] may be made available to the Hydrocarbon Reformer and may include, natural gas, syngas, refinery offgases, methanol, ethanol, petroleum, methane, ethane, propane, butane, hexane, benzene, toluene, xylene, or even waxes or low melting solids such as paraffin wax and naphthalene.
Sequence Step C, Syngas Cooling [C]
[0087] FIG. 3 illustrates Sequence Step C, Syngas Cooling [C], wherein Syngas Cooling Control Volume [C- 1 ] accepts a Sequence Step C Syngas Inlet [C-IN] and outputs a Sequence Step C Syngas Discharge [C-OUT].
[0088] Syngas may be routed through a Sequence Step C Syngas Inlet [C-IN], to a Heat Recovery Steam Generator (HRSG) Superheater [ 8025 ], where heat is indirectly removed from the syngas. The HRSG Superheater is preferably a shell and tube type heat exchanger, with the hot syngas traveling through the tube-side indirectly contacting steam which is located on the shell-side. Heat is transferred from the syngas traveling on the equipment's tube-side to the saturated steam that flows through the heat exchanger shell-side, thus generating a source of superheated steam [ 8 ] discharged from the shell-side of the Heat Recovery Steam Generator (HRSG) Superheater.
[0089] Syngas is transferred from the HRSG Superheater to the Heat Recovery Steam Generator (HRSG) [ 8050 ] through HRSG transfer line [ 10 ] where the syngas is further cooled prior to being discharged from the HRSG through Sequence Step C Syngas Discharge [C-OUT]. The HRSG is preferably a shell and tube type heat exchanger, with the syngas on the tube-side and water on the shell-side. Water [ 12 ] is introduced to a HRSG lower shell-side inlet and used as the heat transfer fluid to remove thermal energy from the syngas. A steam and water mixture [ 14 ] is generated in the shell-side of the HRSG and transferred to the Steam Drum [ 8075 ]. The Steam Drum is operated under pressure control with a pressure transmitter [ 16 ] acting in communication with a pressure control valve [ 18 ] located on the HRSG Superheater shell-side superheated steam [ 8 ] discharge line. When pressure control valve [ 18 ] opens and releases pressure on automatic pressure control, to maintain a steady pressure in the Steam Drum, saturated steam is transferred to the HRSG Superheater through saturated steam transfer line [ 20 ], where steam indirectly contacts the syngas flowing through the HRSG Superheater. The Steam Drum is operated under level control where a level transmitter [ 22 ] located on the vessel acts in communication with a level control valve [ 24 ] located on a water supply line [ 26 ] to provide water to maintain sufficient level in the Steam Drum to allow recirculation of water through the shell-side of the HRSG. A continuous purge of water flows from the Steam Drum through a steam drum continuous blowdown line [ 28 ] to regulate the concentration of suspended and total dissolved solids within the volume of water contained within the Steam Drum.
[0090] Any type of heat exchange system may be used to achieve the syngas cooling functionality prescribed in Sequence Step C. One single heat exchanger may be used, or more than one may be used. Saturated steam may be generated, as opposed to superheated steam. A forced recirculation HRSG cooling water loop may be used as opposed to the disclosed natural thermosiphon configuration.
Sequence Step D, Solids Removal & SVOC Removal [D]
Venturi Scrubber
[0091] FIG. 4 illustrates Sequence Step D, Solids Removal & SVOC Removal [D], wherein Solids Removal & SVOC Removal Control Volume [D- 1 ] accepts an unconditioned syngas through a Solids & SVOC laden Sequence Step D Syngas Inlet [D-IN], and outputs a first depleted syngas stream, which has a reduced amount of solids and SVOC relative to the unconditioned syngas, through a Solids & SVOC-depleted Sequence Step D Syngas Discharge [D-OUT].
[0092] Although any commercially available system capable of removing solids and SVOC from syngas may be employed, the specific combination and configuration of equipment and assets, and methods of operation, disclosed herein, indicate the preferred system to be utilized.
[0093] Two separate block process flow drawing configurations for Solids Removal & SVOC Removal Control Volume [D- 1 ] are disclosed in the accompanying text. These are Option 1 and Option 2 as illustrated in FIG. 4 , and FIG. 9 , respectively. FIG. 5 together with FIG. 6 clarify details of preferred Option 1 of Sequence Step D.
[0094] Cooled unconditioned syngas is routed to a wetted throat Venturi Scrubber [ 8100 ] through Sequence Step D Syngas Inlet [D-IN]. The Venturi Scrubber operates at a temperature below the SVOC condensation temperature and below the dew-point of the excess steam contained within the syngas therefore condensing said SVOC and excess steam out into a liquid phase. Solid char particulates entrained within the syngas come into contact with water provided by a Venturi Scrubber recirculation water line [ 30 ], and solvent provided by a Venturi Scrubber recirculation solvent line [ 32 ], at the divergent section of the Venturi Scrubber and said particulates act as a nuclei for excess steam condensation and are displaced from the vapor phase and into the liquid phase.
Char Scrubber
[0095] An intermediate SVOC-depleted syngas containing steam together with a first mixture comprising SVOC, solids, solvent and water, is routed to the lower section of the Char Scrubber via a Venturi Scrubber to Char Scrubber transfer conduit [ 34 ]. The Char Scrubber serves as an entrainment separator for the Venturi Scrubber and is configured to receive the intermediate SVOC-depleted syngas containing steam and the first mixture, and separately output a first depleted syngas stream and a second mixture comprising SVOC, solids, solvent and water.
[0096] The Char Scrubber, is preferably a vertically oriented cylindrical, or rectangular, pressure vessel having a lower section, and an upper section, along with a central section that contains a quantity of packed media either comprising raschig rings, pall rings, berl saddles, intalox packing, metal structured grid packing, hollow spherical packing, high performance thermoplastic packing, structured packing, synthetic woven fabric, or ceramic packing, or the like, wherein media is supported upon a suitable support grid system commonplace to industrial chemical equipment systems. The upper section of the scrubber preferably contains a demister to enhance the removal of liquid droplets entrained in a vapor stream and to minimize carry-over losses of the sorption liquid. This demister is also positioned above the scrubber spray nozzle system [ 36 ], comprised of a plurality of spray nozzles, or spray balls, that introduce and substantially equally distribute the scrubbing absorption liquid to the scrubber onto the scrubber's central packing section so it may gravity-flow down through the scrubber central section.
[0097] As the syngas passes up through the internal packing of the Char Scrubber, excess steam within the syngas comes into intimate contact with water [ 38 ] and solvent [ 40 ], which are cooled prior to being introduced to the upper section of the Char Scrubber through the scrubber spray nozzle system. Steam is condensed into a liquid phase before being discharged from the Char Scrubber via the Char Scrubber underflow downcomer [ 42 ].
[0098] Intimate gas to liquid contact within the Char Scrubber allows for the solvent to both, absorb SVOC from the syngas, and enable carbon contained within the char, comprised of a carbon and ash mixture, to become oleophilic and hydrophobic permitting said carbon to become suspended within the solvent before both the solvent and carbon are discharged from the Char Scrubber through the Char Scrubber underflow downcomer [ 42 ].
[0099] A Char Scrubber Heat Exchanger [ 8150 ] is installed in the common water recirculation line [ 44 ], and is preferably of the shell and tube type heat exchanger, wherein syngas steam condensate transferred to scrubbing operations resides on the tube-side, and a cooling water supply [ 46 ], and a cooling water return [ 48 ], communicate with the shell-side of the heat exchanger to fulfill the heat transfer requirements necessary to indirectly remove heat from the tube-side steam condensate recirculation scrubbing liquid.
Solvent Selection Definition
[0100] Where the end syngas user is a FT synthesis reactor, the preferred scrubbing solvent is Medium Fraction Fischer-Tropsch Liquid (MFFTL) generated from the downstream FT catalytic synthesis process, however other Fischer-Tropsch products may be used. The ability to generate a valuable scrubbing solvent on-site provides a financial benefit due to operational self-sufficiency thus improving plant operating costs since the facility need not rely upon an outside vendor to furnish the sorption liquid.
[0101] Where the end syngas processing technology is a fuels, power, or chemicals production application, the preferred scrubbing solvent is a degreaser solvent, or a biodegradable, non-toxic, and environmentally safe, industrial cleaning solvent for biodiesel residue, such as BioSol TS 170™, marketed by Evergreen Solutions. Nonetheless, many types of hydrophilic solvents may be used, including, but not limited to, glycerol, rapeseed methyl ester, biodiesel, canola oil, vegetable oil, corn oil, castor oil, or soy oil, listed in decreasing preference.
Immiscibility Definition
[0102] It is to be understood that the water and solvent are immiscible in that they are incapable of being mixed to form a homogeneous liquid. The solvent phase is relatively less dense than the water phase allowing the solvent phase to float on top of the water phase. It is also to be understood that the solvent possesses a relatively greater affinity for the unreacted carbon particulate than the water. This is partly due to the solvent possessing an adhesive tension relative to the carbon solid particulate exceeding that of water. It is also to be understood that the carbon separates immediately and substantially completely from the water phase and floats on the surface as an unagglomerated fine solid particulate substance leaving a clear water phase below.
Continuous Candle Filter Decanter
[0103] A Continuous Candle Filter Decanter [ 8175 ] may be utilized to accept syngas excess steam condensate, solvent, and carbon and ash from the Char Scrubber underflow downcomer [ 42 ]. The Continuous Candle Filter Decanter is configured to receive the second mixture ash from the Char Scrubber underflow downcomer [ 42 ] and separate the water within the second mixture based upon immiscibility so that the SVOC, solids and solvent collect together to form a third mixture above the water within the decanter vessel, the decanter vessel further configured to separately output the water and the third mixture.
[0104] The Continuous Candle Filter Decanter is comprised of an upright tank [ 50 ], made up of two parts, a hollow cylindrical, or rectangular, central section [ 52 ] with a closed dome shaped top [ 54 ]. It has one or more conical lower sections [ 56 a & 56 b ] each terminating at the bottom in a drain port with a suitable drain valve [ 58 a & 58 b ] and a drain line [ 60 a & 60 b ]. These drain lines may be connected to a separate commercially available Filter Cake Liquid Removal System [ 8225 ], preferably of a mechanical pressure filter-belt press, or any similar device that exerts a mechanical pressure on a liquid laden sludge like filter cake substance to separate liquid therefrom.
[0105] A vertical water underflow weir [ 62 ] extends downward from the dome shaped top of the upright tank and is spaced away from and cooperates with the upright vertical housing wall [ 64 ] of the hollow center section to provide an annular passageway [ 66 ] therebetween for passage of the syngas steam condensate water phase into a common water header [ 68 ] taken from various water take-off nozzles [ 70 a & 70 b ], circumferentially positioned around the upper portion of the outer annular passageway. Water may be routed to the water recirculation pump [ 72 ] and transferred to the Char Scrubber and Venturi Scrubber. Water take-off nozzles may be positioned at various points about the upright vertical housing walls, or water may be pumped from various points located on closed dome shaped top. Only two water take-off nozzles are shown for simplicity, however many more are preferred, usually one take-off point for each candle filter bundle, wherein a commercial system may contain about 4 candle filter bundles.
[0106] The vertical water underflow weir is comprised of an upright annular wall that terminates at a height within the pressure vessel deep enough to provide an inner solvent chamber [ 74 ] intended to contain the solvent used for recirculation in the scrubbing system. The solvent chamber is positioned in between the Char Scrubber underflow downcomer [ 42 ] and the vertical underflow weir [ 62 ]. The solvent and water interface layer is contained within the inner solvent chamber [ 76 ], and therefore the solvent and water interface rag-layer [ 78 ] will also be restricted to the inner solvent chamber.
[0107] It is to be understood that the ‘rag-layer’ describes the region wherein the solvent and water interface resides, also the location where unagglomerated carbon may accumulate based on the fact that carbon is more dense than solvent, thus sinking to the bottom of the solvent phase, but being less dense than water, allowing it to float on top of the water phase, or at the water and solvent interface layer.
[0108] The Char Scrubber underflow downcomer extends from the lower section of the Char Scrubber and is disposed within the inner solvent chamber terminating at a height within the solvent chamber at a vertical elevation relatively higher than, and above, the vertical weir underflow height. It is preferential to operate the system so that the solvent and water interface rag-layer resides at the region in the solvent chamber where the downcomer terminates within the solvent chamber.
[0109] The inner solvent chamber, housed within the Continuous Candle Filter Decanter's cylindrical center section, may contain one or more filter bundles [ 80 a & 80 b ] containing a plurality of vertically disposed candle filter elements [ 82 ]. Preferably the elements are of the type which possess a perforated metal support core covered with a replaceable filter cloth, or synonymously termed filter-sock, of woven Teflon cloth with approximate 5-micron pore openings. During filtration, the filter cloth forms a ridged-type structure around the perforated metal core of the filter element and, thus ensuring good adherence of the filter cake during the filtration phase. Filtrate solvent is conveyed through the full-length of each individual candle filter element to the filter bundle common register [ 84 a & 84 b ] and to a filtrate removal conduit [ 86 a & 86 b ]. Only two candle filter bundles are shown in the figure for simplicity. Each filter element is closed at the bottom and allows for only circumferential transference of liquid through the filter sock into the perforations in the metal filter element support core.
[0110] A filtrate process pump [ 88 ], located on the common filtrate suction header [ 90 ], sucks solvent from the inner solvent chamber, through each filter element [ 82 ], of each filter bundle [ 80 a & 80 b ], through each filter bundle filtrate removal conduit [ 86 a & 86 b ] and filtrate register valve [ 92 a & 92 b ], and transfers it via [ 94 ] to an optional SVOC Separation System Control Volume [SVOC- 1 ] where SVOC is removed and an SVOC-depleted solvent is transferred to the Venturi Scrubber and Char Scrubber common solvent recirculation line [ 96 ].
[0111] Pressure transmitters [ 98 a & 98 b ] are installed on each filtrate removal conduit and may be used to monitor the differential pressure across each filter bundle in relation to the filter housing pressure provided by a similar pressure transmitter [ 100 ] located on the vertical housing. In-line flow indicating sight glasses [ 102 a & 102 b ] are installed on each filtrate removal conduit so that a plant operator may visually see the clarity of the filtrate to determine if any candle filter sock element has been ruptured and needs repair.
Backflush System
[0112] Filtrate Backflush Buffer Tank [ 8200 ] accepts SVOC-depleted filtrate solvent from the SVOC-depleted solvent transfer line [ 104 ], discharged from the SVOC Separation System. The tank is positioned in communication with the SVOC-depleted solvent transfer line [ 104 ] and preferably is installed in a vertical orientation relative to it so that solvent may flow via gravity into the tank. The Filtrate Backflush Buffer Tank is equipped with a level transmitter [ 106 ] that acts in communication with an solvent supply level control valve [ 108 ] located on a solvent supply line [ 110 ] which transfers fresh solvent to the system, either to the Filtrate Backflush Buffer Tank or to the Char Scrubber underflow downcomer (not shown).
[0113] The solvent backflush pump [ 112 ] accepts SVOC-depleted filtrate solvent from the Filtrate Backflush Buffer Tank through filtrate transfer conduit [ 114 ] and recirculates the solvent back to the Filtrate Backflush Buffer Tank through backflush tank recirculation line [ 116 ]. A restriction orifice [ 118 ], or similar pressure letdown device, such as an iris-type adjustable orifice valve, is located in-line to create a high pressure recirculation reservoir within the backflush tank recirculation line [ 116 ], and its connected piping network, to accommodate backflushing of the candle filter bundles.
Candle Filter Operation Philosophy
[0114] The best mode of operation for realizing a continuous filtrate stream encompasses operating the filtration system in a manner which allows for periodic backflushing of the filter element cloth surface in-situ by reversing the flow of liquid scrubbing solvent filtrate through the filter elements. The backwashing dislodges any accumulated filter cake allowing it to sink to the bottom of the conical section of the filter housing for removal of the system as a thick, paste-like, filter cake substance. Experimental results have consistently and repeatedly shown that regeneration of the filter elements to realize sustainable and continuous operation of the filter coincides with utilizing SVOC-depleted filtrate solvent as the backflush filter liquid. However the system will function as intended while utilizing alternate mediums to cleanse filter element surfaces, such as SVOC laden filtrate solvent, syngas steam condensate, or a vapor source, such as inert nitrogen or carbon dioxide.
[0115] It is preferred to utilize differential pressure across a filter bundle as the main variable to determine when to undergo a back flushing cycle, as opposed to using manual predetermined periodic time duration intervals, or using the reduction in flow through the filter bundles as the variable dictating when to commence filter back flushing, (synonymously termed ‘filter cleaning’, or ‘filter backwashing’, ‘in-situ filter cleaning’, or ‘filter surface in-situ regeneration’). This is because experimental results have shown that a filter bundle differential pressure between 6 and 10 PSI is commensurate with preferable cake thickness of 20 to 35 millimeters. In contrast, using manual predetermined periodic time duration intervals as the sole mechanism to determine when to commence filter cleaning, often results in operational impairment, in that ‘cake bridging’ more readily occurs. ‘Cake bridging’ is well known in the art of filtration. It may be described as a large mass of agglomerated suspended solids filling the spaces between the filter elements and thus posing a challenge to regenerate in-situ, frequently requiring process interruption for physical cleaning and removal of the heavy, gelatinous filter cake.
[0116] In-situ filter cleaning may be accomplished by reversing the flow of liquid through the filter element thereby dislodging filter cake from the cloth surface thus allowing it to sink to the bottom of the water phase within the lower filter chamber conical section. This affords operations the luxury of minimizing losses of valuable solvent while draining the filter cake from the system.
Candle Filter Operating Procedure
[0117] FIG. 7 depicts the preferred operating procedure for continuous filtration of suspended particulate solids from SVOC laden scrubbing solvent. Filtration [step 950 ] cooperates with the cyclic-batch filter in-situ cleaning steps of: filter bundle isolation [step 952 ]; filtrate backflush [step 954 ]; filter cake sedimentation [step 956 ]; filter cake discharge start [step 958 ]; filter cake discharge end [step 960 ]; and filtration restart preparation [step 962 ].
[0118] In step 950 , (filtration), filtration proceeds and the filter bundle pressure drop is monitored. As a filtration cycle progresses, solids are deposited onto the surface of each filter element and adhere to its surface until a nominal target differential pressure drop between around 6 to 10 PSI is attained, which is proportionate to a predetermined thickness of 20 to 35 millimeters. If the filter bundle pressure drop is lower than the nominal target differential pressure drop, the filtering cycle continues until the nominal target differential pressure drop is reached. When a filter bundle has reached its nominal target differential pressure drop, a filter cleaning cycle will commence, which begins with step 952 (filter bundle isolation). In addition to FIG. 7 , the sequential steps encompassing filtration and filter cleaning can be further illuminated by using FIG. 6 , which visually indicate some of the valve sequencing involved, as indicated by open and closed valve positions, illustrated by ‘non-darkened-in valves’ and ‘darkened-in valves’, respectively, of filtrate register valve [ 92 a & 92 b ], backflush filtrate regen valves [ 120 a & 120 b ] (located on respective filtrate backflush regen conduits [ 122 a & 122 b ]), as well as filter cake drain valves [ 58 a & 58 b ] located on each lower conical section. FIG. 6 , indicates filtrate register valve 92 a open and 92 b closed. It also shows backflush filtrate regen valves 120 a closed and 120 b open. FIG. 6 further depicts filter cake drain valves 58 b open and 58 a closed. It should be understood that these valves probably will never actually be opened at the same time; FIG. 6 , together with FIG. 7 , offer insight to the spirit of the operation, to clarify the preferred operating philosophy, and to provide the reader with a genuine appreciation for the sequencing involved.
[0119] When a nominal target pressure drop across a filter bundle is attained, the filter cake material must be dislodged from filter elements of a given filter bundle, and thus step 952 (filter bundle isolation) proceeds, which involves isolating the relevant filter bundle by closing the filtrate register valve 92 b to stop filtration on that given filter bundle. Once the filtrate register valve has been closed, to isolate the filter bundle that exhibits a pressure drop higher or equal to a nominal target pressure drop, step 954 may proceed. Step 954 , (filtrate backflush), involves transferring filtrate solvent from the pressurized recirculation loop [ 116 ], provided by the solvent backflush pump [ 112 ], through the relevant filtrate back-flush regen conduit [ 122 b ], injected though the filtrate regen valve [ 120 b ] where the solvent then countercurrently enters the filter bundle filtrate removal conduit [ 86 b ] and is transferred to the filter elements in need of regeneration.
[0120] It is to be understood that the operating discharge pressure of the solvent backflush pump [ 116 ], that required for the filtrate to be transferred countercurrent to operational flow to gently expand the filter cloth allowing for the cake to be discharged from the filter element surface, is higher than the operating pressure in the Continuous Candle Filter's upright tank [ 50 ], preferably between 15 to 20 PSI greater than the filter housing operating pressure, which operates between 30 and 60 PSIG. The pressure difference between the filtrate transferred to the system from the solvent backflush pump [ 116 ], and the upright tank [ 50 ], is the pressure necessary for the purification of the filter surfaces. It is to be understood that a typical backflush with SVOC-depleted filtrate solvent, in step 954 , requires that the backflush filtrate regen valve [ 120 b ] need be left open for a duration of time less than or equal to 10 seconds.
[0121] After the SVOC-depleted filtrate solvent has been injected through the filter bundle, and once the backflush regen valve has been returned to a closed position, step 956 may commence. Step 956 (filter cake sedimentation) entails allowing a settling time sequence for a duration of time less than or equal to 30 seconds to allow the agglomerated dislodged filter cake solids to sink through both, the solvent phase, and the water phase, thus permitting sufficient time to allow the filtration induced forcibly agglomerated filter cake solids to settle to the bottom lower conical drain section.
[0122] Step 958 (filter cake discharge start) involves opening the respective regenerated filter bundle's filter cake drain valve [ 58 b ] to allow transference of an agglomerated paste-like carbon particulate filter cake material from the system. The process control signal generation mechanism required to end step 958 involves monitoring the signal output from a presence/absence detection flange mounted instrument [ 124 b ], also termed an impedance-sensing device, or the like, which may be installed just upstream prior to the filter cake drain valves to serve the purpose of further automating the system by indicating when the thick paste-like filter cake material has left the system.
[0123] Alternately the sensors may be furnished by the commercial vendor to detect the presence or absence of water within the pipeline thus acting as a control mechanism for closing the drain valve. If the process control signal indicates that the filter cake is being drained from the system, step 958 continues. If, on the other hand, the process control signal indicates that the filter cake has left the system, step 958 will end, and step 960 may begin. Step 960 (filter cake discharge end) entails closing the respective filter cake drain valve [ 58 b ] since solids have been discharged from the system. After step 960 has transpired, step 962 (filtration restart preparation) may commence which entails opening the respective filter bundle's filtrate register valve [ 92 b ] to again commence filtration on the regenerated filter bundle, thus allowing step 950 to commence again, then allowing the filtration and regeneration cycle to repeat itself.
Filter Cake Liquid Removal System
[0124] After the filter cake material is removed from the candle filter vessel, it may be transferred to any sort of commercially available Filter Cake Liquid Removal System [ 8225 ], preferably a belt filter press, or any similar device which applies mechanical pressure to an agglomerated sludge paste-like filter cake to remove residual liquid therefrom. Liquid removed from the filter cake [ 124 ] may be transferred to the plant waste water header, whereas the liquid depleted solids [ 126 ] may be transferred to another location for Liquid Depleted Solids Collection [ 8250 ].
Step D, Option 1 , Operation
[0125] FIG. 8 underlines the principles dictating the philosophy of operation of Option 1 of Solids Removal & SVOC Removal Control Volume [D- 1 ] as depicted in FIG. 4 , which are as follows:
[0126] Step D 1 a:
contacting the unconditioned syngas with a solvent and water to reduce the temperature of the syngas to below the SVOC condensation temperature to thereby form an intermediate SVOC-depleted syngas containing steam, and a first mixture comprising SVOC, solids, solvent and water;
[0128] Step D 1 b:
removing steam from the intermediate SVOC-depleted syngas containing steam to form: (i) a first depleted syngas stream which has a reduced amount of SVOC relative to the unconditioned gas stream, and (ii) a second mixture comprising SVOC, solids, solvent and water;
[0130] Step D 1 c:
separating the water within the second mixture based upon immiscibility so that the SVOC, solids and solvent collect together to form a third mixture above the water; separating the solids from the SVOC and solvent in a vessel having at least one liquid phase candle filter such that the solids agglomerate on a surface of the candle filter and form a filter cake having density greater than that of water within the vessel;
[0132] Step D 1 d:
Backflushing the candle filter to loosen the filter cake so that the filter cake sinks into the water within the vessel; and
[0134] Step D 1 e:
Removing the filter cake from a bottom of the vessel.
Step D, Option 2
[0136] In an alternate, non-limiting embodiment, the immiscible liquid separation and continuous filtration functionalities of the Continuous Candle Filter Decanter [ 8175 ] may be decoupled.
[0137] Option 2 of Solids Removal & SVOC Removal Control Volume [D- 1 ], as depicted in FIG. 9 and FIG. 10 , utilizes a Decanter [ 8275 ] and Continuous Candle Filter [ 8300 ], which serve a similar function as the Continuous Candle Filter Decanter [ 8175 ]. Separation of immiscible liquids followed by separation of SVOC from the solvent filtrate is the guiding principle to be achieved by installation of the configuration disclosed in Option 2 .
[0138] The purpose of the Continuous Candle Filter Decanter [ 8175 ], of Step D Option 1 , is to combine the functionality of density separation of liquids together with filtration separation of solids from liquids. It further automates an otherwise batch-wise filter operation so that a continuous cyclic-batch system is realized. As illustrated in FIG. 9 , the Decanter [ 8275 ] and Continuous Candle Filter [ 8300 ] are separate from one another.
[0139] FIG. 9 depicts the Decanter [ 8275 ] and Continuous Candle Filter [ 8300 ] in communication through a solids & SVOC laden solvent filtrate transfer line [ 128 ]. It further depicts the Continuous Candle Filter [ 8300 ] in communication with the SVOC Separation System Control Volume [SVOC- 1 ] through a SVOC laden solvent filtrate transfer line [ 130 ].
[0140] Decanters are well known liquid density separation unit operations commonplace to commercial industrial systems. Furthermore, similarly, candle filters, or the like, are commercially available and their installation, integration, and operation are well known to a person possessing an ordinary skill in the art to which it pertains.
[0141] FIG. 10 outlines the principles dictating the philosophy of operation of Option 2 of Solids Removal & SVOC Removal Control Volume [D- 1 ] as depicted in FIG. 9 , which are as follows:
[0142] Step D 1 a:
contacting the unconditioned syngas with a solvent and water to reduce the temperature of the syngas to below the SVOC condensation temperature to thereby form an intermediate SVOC-depleted syngas containing steam, and a first mixture comprising SVOC, solids, solvent and water;
[0144] Step D 1 b:
removing steam from the intermediate SVOC-depleted syngas containing steam to form: (i) a first depleted syngas stream which has a reduced amount of SVOC relative to the unconditioned gas stream, and (ii) a second mixture comprising SVOC, solids, solvent and water;
[0146] Step D 1 ca:
Separating the water within the second mixture based upon immiscibility so that the SVOC, solids and solvent collect together to form a third mixture above the water;
[0148] Step D 1 cb:
separating the solids from the SVOC and solvent in a vessel having at least one liquid phase candle filter such that the solids agglomerate on a surface of the candle filter and form a filter cake having density greater than that of water within the vessel;
[0150] Step D 1 d:
Backflushing the candle filter to loosen the filter cake so that the filter cake sinks into the water within the vessel; and
[0152] Step D 1 e:
Removing the filter cake from a bottom of the vessel.
SVOC Separation System
[0154] FIG. 11 and FIG. 12 illustrate options for separating SVOC from the filtrate scrubbing solvent.
SVOC Flash Separation System
[0155] The preferred application to remove SVOC from the syngas as depicted in Solids Removal & SVOC Removal Control Volume [D- 1 ], encompasses the utilization of a scrubbing solvent that sorbs SVOC from the syngas. SVOC removal from the scrubbing solvent must take place in order to realize continuous recycle of the scrubbing solvent as well as to avoid the buildup of SVOC within the system leading to operational impairment of the scrubbing operations.
[0156] In order to continuously recycle absorption scrubbing liquid, a SVOC Flash Separation System, as depicted in FIG. 11 , may be employed to flash SVOC from the scrubbing solvent. Preferably this system is employed together with the use of a vacuum system, condenser system, and liquid SVOC collection equipment permitting the recovery of a SVOC product.
[0157] FIG. 11 depicts the preferred non-limiting embodiment for the SVOC Separation System Control Volume [SVOC- 1 ]. SVOC laden filtrate scrubbing solvent is transferred from solvent and char filtration operations through a filtrate solvent transfer line [ 94 ] and routed to the inlet of a SVOC Flash Tank Heat Exchanger [ 8325 ], which is preferably of a shell and tube type heat exchanger. Steam, or another heat source, may communicate with the shell-side of the heat exchanger through a steam inlet line [ 132 ] and a steam discharge line [ 134 ] to transfer heat to the SVOC laden filtrate solvent traveling through the exchanger's tube-side prior to being transferred to the SVOC Flash Tank [ 8350 ]. SVOC laden filtrate scrubbing solvent is discharged from the exchanger's tube-side and routed through a SVOC laden filtrate solvent Flash Tank transfer line [ 136 ] where it then flows through a pressure letdown device [ 138 ], comprised of either a valve, or restriction orifice, that is positioned just upstream of the inlet to the SVOC Flash Tank. Upon release to the lower pressure environment of the SVOC Flash Tank, the SVOC liquid fraction is vaporized, or flashed, from the SVOC laden filtrate solvent and enters the SVOC flash transfer conduit [ 140 ] for condensation and collection of the SVOC product. A SVOC-depleted filtrate solvent is expelled from the lower section of the SVOC Flash Tank where it enters a SVOC-depleted solvent transfer line [ 142 ]. A SVOC-depleted solvent transfer pump [ 144 ], routes the solvent to a Solvent Cooler [ 8375 ] through a solvent transfer line [ 146 ], or it may transfer the solvent back to the SVOC Flash Tank Heat Exchanger [ 8325 ] through a solvent recycle line [ 148 ].
[0158] A cooling water supply [ 150 ] and a cooling water return [ 152 ] communicate with the shell-side of the Solvent Cooler [ 8375 ] and provide the thermal capacity to remove heat from the solvent traveling through the tube-side of the exchanger.
[0159] The SVOC Flash Tank is preferably a vertical cylindrical tank, however it may be a horizontal flash tank with provided distribution pipe, and may be equipped with an impingement baffle [ 154 ] to provide a sudden flow direction change of the flashing SVOC laden filtrate solvent. A plurality of spray nozzles [ 156 ] are positioned in the upper section of the SVOC Flash Tank and are utilized for intermittent washing with a clean in place (CIP) agent transferred to the system through a CIP agent transfer line [ 158 ] and a CIP agent isolation valve [ 160 ]. Cleaning of the vessel preferably is performed only when the solvent is isolated from the SVOC Flash System. The spray nozzles [ 156 ] may also be provided with a source of cooled SVOC-depleted solvent through a cooled SVOC-depleted solvent transfer line [ 162 ] routed from the discharge of the Solvent Cooler [ 8375 ].
[0160] The SVOC Flash Tank Heat Exchanger [ 8325 ] increases the temperature of the SVOC laden solvent stream to above the flash point of SVOC and lesser than, and not equal, to the flash point temperature of the scrubbing solvent. This is to permit vaporization of only the SVOC fraction within the solvent and SVOC liquid mixture upon release to a lower pressure across the pressure letdown device [ 138 ].
[0161] A SVOC Condenser [ 8400 ] accepts SVOC laden vapors from the SVOC vapor transfer conduit [ 140 ] and condenses the SVOC into a liquid state prior to discharging the liquid SVOC from the system through a SVOC Separation System Control Volume SVOC Discharge [SVOC-OUT].
[0162] A SVOC vacuum system transfer line [ 164 ] connects the SVOC Vacuum System [ 8425 ], with the SVOC Condenser [ 8400 ]. The Vacuum system is preferably a liquid ring vacuum pump that uses a liquid SVOC seal fluid [ 166 ] within its pump casing (not shown).
[0163] A cooling water supply [ 170 ] and a cooling water return [ 172 ] communicate with the shell-side of the SVOC Condenser [ 8400 ] and provide the thermal capacity to condense SVOC traveling through the tube-side of the exchanger into a liquid phase.
SVOC Membrane Separation System
[0164] In an alternate non-limiting embodiment, selective sorptive permeation of SVOC from the scrubbing liquid may be employed, as depicted in FIG. 12 which portrays the SVOC Sorptive Separation System. Liquid phase sorption applications, not only including pervaporation membrane processes, may be employed to separate the SVOC from the SVOC laden scrubbing solvent liquid mixture due to selective diffusion of the SVOC molecules based on molecular diameter and polarity.
[0165] SVOC laden filtrate scrubbing solvent may be transferred from the filtrate solvent transfer line [ 94 ] to the inlet of a SVOC Sorptive Separator [ 8475 ]. It is preferred to utilize a SVOC Sorptive Separator [ 8475 ] in a capacity to realize liquid phase pervaporative sorption separation of SVOC from a solvent laden filtrate stream. However a packed bed of adsorbent, either polymeric styrene based adsorbents, or 10 angstom aluminosilicate molecular sieve adsorbents, or a suitable sorption medium possessing an preferential sorption of SVOC from a scrubbing solvent may also be utilized to accomplish a similar result.
[0166] The SVOC Sorptive Separator [ 8475 ] is preferentially comprised of a commercially available permeation unit, preferably a shell and tube device utilizing a tubular membrane selective to hydrophobic non-polar solvents preferably in the form of a PEEK based membrane cast inside a hollow fiber tube.
[0167] The SVOC Sorptive Separator [ 8475 ] may also contain a cluster of membrane elements, and more than one permeation unit may be used to create multiple pervaporation modules, or even multiple stages of pervaporation modules may be utilized. Although a plate and frame type unit may be utilized in conjunction with membrane sheets, the shell and tube type system is preferred due to its ease in manufacture and lower capital cost.
[0168] The SVOC Sorptive Separator [ 8475 ] contains a porous membrane [ 174 ], preferably with a porous chemical resistant coating [ 176 ], having a SVOC laden solvent membrane process surface [ 178 a ], that is exposed to the SVOC laden filtrate scrubbing solvent, and an opposing SVOC permeate membrane process surface [ 178 b ], where the SVOC permeate is volatilized therefrom by a driving force created by preferably a combination of a vacuum driven and a temperature driven gradient created by a downstream vacuum system and condenser as previously described.
[0169] A Guard Filter [ 8450 ] accepts SVOC laden filtrate solvent from the filtrate solvent transfer line [ 94 ] prior to routing it to the SVOC Sorptive Separator [ 8475 ] through a second filtrate solvent transfer line [ 180 ]. The Guard Filter [ 8450 ] is in place to mediate any membrane fouling which may arise due to fine particulate matter blocking membrane flow channels, contributing to clogging of effective membrane void spaces and ultimately causing a gradual decline in the membrane SVOC permeation rate. The Guard Filter [ 8450 ] is preferably an easy access metal filter-bag housing preferably containing a heavy-duty polyester felt filter bag of 0.5 micron effective pore size.
Sequence Step E, Chlorine Removal [E]
[0170] FIG. 13 illustrates Sequence Step E, Chlorine Removal [E], wherein Chlorine Removal Control Volume [E- 1 ] accepts a chlorine laden Sequence Step E Syngas Inlet [E-IN], and outputs a chlorine depleted Sequence Step E Syngas Discharge [E-OUT].
[0171] The Chlorine Scrubber [ 8500 ], configured similar to the Char Scrubber [ 8125 ], is also a vertically oriented cylindrical, or rectangular, pressure vessel having a lower section, and an upper section, along with a central section that contains a specified quantity of packed absorption media, which is supported upon a suitable support grid system commonplace to industrial chemical equipment systems. The upper section of the scrubber preferably contains a demister that is positioned above a scrubber spray nozzle system [ 236 ] which introduces the scrubbing absorption liquid to the scrubber.
[0172] The purpose of the Hydrogen Chloride Scrubber is to remove trace amounts of hydrogen chloride from the syngas by using water condensed from residual steam contained within the syngas as the main scrubbing absorption liquid. It also serves the function to remove any residual particulate elutriated in the syngas.
[0173] Syngas enters the lower section of the Hydrogen Chloride Scrubber and passes up through the scrubber's central section where the syngas vapor comes into intimate contact with the water scrubbing liquid traveling countercurrently via gravity flow down through the scrubber's packing. Water is condensed out of the vapor phase and enters the lower section of the scrubber. A level control loop, comprising a level transmitter [ 200 ], positioned on the lower section of the scrubber, and a level control valve [ 202 ], may be automatically operated to permit water to be bled from the scrubber water recirculation piping [ 238 ], via a waste water transfer conduit [ 240 ], to maintain a steady liquid level within the lower section of the scrubber. A scrubber water recirculation pump [ 276 ], accepts water from the lower section of the scrubber, through the pump suction piping [ 242 ], and transfers the water through a Hydrogen Chloride Scrubber Heat Exchanger [ 8525 ], prior to injecting the water into the scrubber, via the main recirculation piping [ 238 ], which routes the water through the scrubber's spray nozzle system and into the upper section of the scrubber where the flow of liquid is directed downwards onto the scrubber central packing. The Hydrogen Chloride Scrubber Heat Exchanger [ 8525 ] is preferably of the shell and tube type, wherein a cooling water supply [ 246 ], and a cooling water return [ 248 ], communicate with the shell-side of the heat exchanger to fulfill the heat transfer requirements necessary to indirectly remove heat from the process side steam condensate recirculation liquid. Process water [ 214 ] may be transferred to the scrubber water recirculation piping, or the lower section of the scrubber.
Sequence Step F, Sulfur Removal [F]
[0174] FIG. 14 illustrates Sequence Step F, Sulfur Removal [F], wherein Sulfur Removal Control Volume [F- 1 ] accepts a sulfur laden Sequence Step F Syngas Inlet [F-IN], and outputs a sulfur-depleted Sequence Step F Syngas Discharge [F-OUT].
[0175] The Sulfur Scrubber [ 8550 ] is configured similar to the Chlorine Scrubber [ 8500 ]. The upper section of the scrubber preferably contains a demister that is positioned above a scrubber spray nozzle system [ 336 ] which introduces the scrubbing absorption liquid to the scrubber. Syngas enters the lower section of the Sulfur Scrubber and passes up through the scrubber's central section where the syngas vapor comes into intimate contact with a hydrogen sulfide scavenger scrubbing liquid traveling countercurrently via gravity flow downward through the scrubber's packing. The Sulfur Scrubber preferentially utilizes a hydrogen sulfide scavenger as the main scrubbing fluid which is preferably a dilute, nonregenerable, water-soluble, triazine derived solution, preferably of Nalco EC9021A product, diluted with water to between a 0.01 and 1 wt % triazine solution mixture. Glyoxal from BASF, SE-100 H2S Hydrogen Sulfide Scavenger from Sepcor, DTM Triazine from DThree Technology, or Baker Hughes' Petrolite SULFIX™ H2S scavengers may alternately be used. The use of a regenerable hydrogen sulfide scavenger fluid may also be used.
[0176] The Sulfur Scrubber is equipped with a level transmitter [ 300 ], positioned on the lower section of the scrubber, which cooperates with a level control valve [ 302 ] located on a waste transfer conduit [ 340 ]. The recirculation pump [ 376 ] accepts a dilute triazine solution from the lower section of the scrubber, through its pump suction piping [ 342 ], and pumps the liquid to the upper section of the scrubber through the recirculation piping [ 338 ] and through a plurality of spray nozzles which spray the flow downwards onto the scrubber's centrally located packed section.
[0177] A source of process water [ 314 ], along with a source of a fresh concentrated sulfur scavenger derived solution [ 316 ], are available to be injected into the Sulfur Scrubber system, preferably into the recirculation piping [ 338 ].
[0178] Any type of sulfur removal system may be used to achieve the syngas cooling functionality prescribed in Sequence Step F. Some alternatives may be, including, but not limited to, wet limestone scrubbing systems, spray dry scrubbers, claus processing system, solvent based sulfur removal processes such as the UC Sulfur Recovery Process (UCSRP), low-temperature or refrigerated solvent-based scrubbing systems using amines or physical solvents (i.e., Rectisol, Selexol, Sulfinol), high temperature sorbents, glycol ether, diethylene glycol methyl ether (DGM), regenerable and non-regenerable sorbents, molecular sieve zeolites, calcium based sorbents, FeO, MgO or ZnO-based sorbents or catalysts, Iron Sponge, potassium-hydroxide-impregnated activated-carbon systems, impregnated activated alumina, titanium dioxide catalysts, vanadium pentoxide catalysts, tungsten trioxide catalysts, sulfur bacteria (Thiobacilli), sodium biphospahte solutions, aqueous ferric iron chelate solutions, potassium carbonate solutions, alkali earth metal chlorides, magnesium chloride, barium chloride, crystallization techniques, bio-catalyzed scrubbing processes such as the THIOPAQ Scrubber, or hydrodesulphurization catalysts.
Sequence Step G, Particulate Filtration [G]
[0179] FIG. 15 illustrates Sequence Step G, Particulate Filtration [G], wherein the Particulate Filer [ 8575 ] situated within the Particulate Filtration Control Volume [G- 1 ] accepts a particulate laden Sequence Step G Syngas Inlet [G-IN], and outputs a particulate depleted Sequence Step G Syngas Discharge [G-OUT].
Sequence Step H, Syngas Compression [H]
[0180] FIG. 16 illustrates Sequence Step H, Syngas Compression [H], wherein the Syngas Compressor [ 8600 ] accepts a Sequence Step H Syngas Inlet [H-IN], and outputs a Sequence Step H Syngas Discharge [H-OUT]. A gaseous hydrocarbon source [HC-IN] may be optionally routed to the inlet of the Syngas Compressor [ 8600 ] and may include, natural gas, syngas, refinery offgases, naphtha, methanol, ethanol, petroleum, methane, ethane, propane, butane, hexane, benzene, toluene, xylene, or naphthalene, or the like.
Sequence Step I, VOC Removal [I]
[0181] FIG. 17 depicts Sequence Step I, VOC Removal [I], wherein VOC Removal Control Volume [I- 1 ] accepts a VOC laden Sequence Step I Syngas Inlet [I-IN], and outputs a VOC-depleted Sequence Step I Syngas Discharge [I-OUT].
[0182] VOC removal systems are not conventionally found within syngas cleaning or conditioning processes. Experimental results have consistently and repeatedly shown that without Sequence Step I, VOC Removal [I] in place sulfur removal systems could be inhibited downstream allowing contaminants to pass through the system and poison catalysts that are not sulfur tolerant.
[0183] In one non-limiting embodiment, VOC may be removed from syngas by utilizing a heat exchange adsorption process that combines thermal swing regeneration with vacuum pressure swing adsorption (VPSA), as depicted in FIG. 18 .
[0184] In another non-limited embodiment, VOC may be removed from syngas by utilizing a fluidized particulate bed adsorption system wherein VOC saturated adsorbent is regenerated utilizing a vacuum assisted thermal swing desorption process as depicted in FIG. 19 .
Sequence Step I, Option 1
[0185] FIG. 18 depicts Option 1 of Sequence Step I which discloses a separation system that may be used to remove VOC from syngas. The figure portrays a VPSA system with thermal swing desorption capabilities.
[0186] VPSA is a gas separation process in which the adsorbent is regenerated by rapidly reducing the partial pressure of the adsorbed component, either by lowering the total partial pressure or by using a purge gas.
[0187] In a VPSA system, regeneration is achieved by first stopping feed flow, then depressurizing the adsorbent, usually by passing regeneration gas through the bed counter-current to the feed direction. The regenerating gas is generally free of impurities.
[0188] VPSA systems have certain inherent disadvantages, mostly attributed to the short cycle time that characterizes VPSA. In each cycle of operation, the adsorbent is subjected to a feed period during which adsorption takes place, followed by depressurization, regeneration, and repressurization. During the depressurization, the feed gas in the bed is vented off and lost, which is referred to as a “switch loss.” The short cycle time in the VPSA system gives rise to high switch losses and, because the cycle is short, it is necessary that the repressurization is conduced quickly. This rapid repressurization causes transient variations in the feed and product flows, which can adversely affect the plant operation, particularly in the operation of processes downstream of the adsorption process.
[0189] VPSA is best used for components that are not too strongly adsorbed. On the other hand, thermal swing adsorption (TSA) is preferred for very strongly adsorbed components, since a modest change in temperature produces a large change in gas-solid adsorption equilibrium. In the temperature swing process, to achieve regeneration, is it necessary to supply heat to desorb the material. Following regeneration of the sorbent by heating, the sorbent preferably is cooled prior to the next adsorption step, preferably by transferring a cooling fluid, not only including water, through the thermal transfer chambers of each Aromatic Hydrocarbon Micro-Scale Heat Exchange Adsorber [ 8625 A&B].
[0190] In one embodiment, each Aromatic Hydrocarbon Micro-Scale, also termed Microchannel, Heat Exchange Adsorber [ 8625 A&B] includes one or more adsorption chambers [ 402 ] each of which may be tubular or rectangular in shape and each chamber is separated from the adjacent chamber(s) by a thermal transfer chamber [ 404 ]. Each adsorption chamber is provided with a feed inlet [ 406 a & 406 b ] for introducing VOC laden syngas, a product outlet [ 408 a & 408 b ] for removing VOC-depleted syngas from the adsorption chamber, and a particulate bed [ 410 ] comprising sorbent particles disposed within the chamber. It is desirable for the adsorption chambers to be relatively narrow to ensure rapid heat transfer, and thus is it our realization that a micro-scale heat exchanger, also termed a microchannel heat exchanger, is the preferred unit operation to be utilized in this particular application. In another non-limiting embodiment, each Aromatic Hydrocarbon Adsorber [ 8625 A&B] are comprised of fixed beds without thermal transfer chambers [ 404 ]. It is to be understood that although FIG. 18 depicts parallel first and second adsorbers capable of being operated such that while the first heat exchange adsorber is in an adsorption mode, the second heat exchange adsorber is in a regeneration mode, more than two adsorbers may be used so that one adsorber is off-line.
[0191] The particulate bed preferably contains an adsorption medium that selectively adsorbs VOC into the pores of adsorbent versus any other syngas constituents. In one embodiment, the adsorbent is a styrene based polymeric adsorbent, such as Dowex Optipore V503, or the like. In another embodiment, the adsorbent may be made up of molecular sieves, zeolites, catalyst materials, silica gel, alumina, activated carbon materials, or combinations thereof.
[0192] Each thermal transfer chamber is equipped with thermal transfer chamber inlet valve [ 412 a & 412 b ]. A coolant material, not only including water, or a heating material, not only including steam, may be introduced into the thermal transfer chamber. The coolant material may remove heat from the adjacent adsorption chambers by thermal transfer. The heating material can add heat to the adjacent adsorption chambers also by thermal transfer.
[0193] When the first adsorber unit [ 8625 A] is in an adsorption mode, the second adsorber [ 8625 B] is in regeneration mode where the second adsorber is first depressurized, then purged with the VOC-depleted syngas stream and finally re-pressurized. During this part of the cycle, the first inlet valve [ 414 a ] is open and the second first inlet valve [ 414 b ] is closed directing the syngas feed from line [I-IN] into the first adsorber [ 8625 A]. As the VOC laden syngas passes through the adsorber [ 8625 A], VOC adsorbate is selectively adsorbed into the pores of the adsorbent and the VOC-depleted syngas passes through a first product outlet valve [ 416 a ] and transferred from the VOC separation system through Sequence Step I Syngas Discharge [I-OUT]. During the entire regeneration process, second product outlet valve [ 416 b ] is closed to prevent flow of regenerate into the VOC-depleted syngas stream.
[0194] Under regeneration conditions, the second adsorber [ 8625 B] is first depressurized. During depressurization, both the first purge inlet valve [ 418 a ] and second purge inlet valve [ 418 b ] are closed to prevent purge from entering the second adsorber [ 8625 B] during depressurization. The first depressurization valve [ 420 a ] is closed to prevent flow of the VOC laden syngas stream [I-IN] into the regenerate product line [ 430 ]. The first thermal transfer chamber inlet valve [ 412 a ] is closed to prevent heat addition to the first adsorber [ 8625 A] undergoing adsorption, and the second thermal transfer chamber inlet valve [ 412 b ] on the second adsorber [ 8625 B] is open to allow transfer of heat to the regenerating VOC saturated adsorbent. The second depressurization outlet valve [ 420 b ] is open allowing flow from the second adsorber [ 8625 B] through the regenerate product line [ 430 ]. The regenerate product will contain a mixture of syngas and VOC. The regenerate product line is under a vacuum condition as a result of the VOC Vacuum System [ 8675 ]. The regenerate product flows freely from the pressurized second adsorber [ 8625 B] along the regenerate product line [ 430 ].
[0195] Once the second adsorber is fully depressurized, the second purge inlet valve [ 418 b ] is opened allowing flow of VOC-depleted syngas to purge the VOC that is selectively adsorbed in the pores of the adsorbent and withdraw such purge stream along regenerate product line [ 430 ] under vacuum conditions. Simultaneous to the time when the purge inlet valve is opened, the second adsorber's thermal transfer chamber inlet valve [ 412 b ] is opened to indirectly transfer thermal energy to the depressurized regenerating adsorber [ 8625 B] to aide the removal of VOC adsorbate from the pores of the adsorbent which is under vacuum conditions. Once the purge and heat addition steps are complete for the second adsorber [ 8625 B], depressurization outlet valve [ 420 b ] is closed while purge inlet valve [ 418 b ] remains open so that VOC-depleted syngas from the first adsorber [ 8625 A] can pressurize the second adsorber [ 8625 B] to the same pressure as the first adsorber [ 8625 B]. Coolant may be exchanged for the heat source transferred to the second adsorber [ 8625 B] through the second thermal transfer chamber inlet valve [ 412 b ] and into the thermal transfer chamber [ 404 ] of the second adsorber [ 8625 B] to cool the adsorbent media within the adsorption chamber to prepare it for the next adsorption sequence.
[0196] Once the second adsorber [ 8625 B] is fully pressurized, it is ready for its function to switch from regeneration to adsorption. At this point, the adsorbent in the first adsorber [ 8625 A] has selectively adsorbed a considerable amount of VOC. The first adsorber [ 8625 A] is ready for regeneration. The two beds switch function. This occurs by the following valve changes. The first product outlet valve [ 416 a ] is closed, and the first inlet valve [ 414 a ] is closed. The first purge inlet valve [ 418 a ] remains closed, and the first depressurization outlet valve [ 420 a ] is opened to begin depressurization of the first adsorber [ 8625 A]. The second thermal transfer chamber inlet valve [ 412 b ] is closed and the first thermal transfer chamber inlet valve [ 412 a ] is opened to allow thermal energy to be transferred to the first adsorber [ 8625 A] thermal transfer chamber [ 404 ].
[0197] Adsorption begins for the second adsorber [ 8625 B] with the following valve arrangement. The second depressurization outlet valve [ 420 b ] remains closed. The second purge inlet valve [ 418 b ] is closed. The second product outlet valve [ 416 b ] is opened, and the first inlet valve [ 414 b ] is opened to facilitate flow from the VOC laden syngas stream [I-IN] into the second adsorber and flow of VOC-depleted syngas from the second adsorber [ 8625 B] through second product outlet valve [ 416 b ] into the VOC-depleted syngas stream [I-OUT]. The regeneration process as described above for the second adsorber [ 8625 B] is repeated for the first adsorber [ 8625 A].
[0198] Preferably, the regeneration occurs at a pressure below atmospheric pressure under a vacuum created by the VOC Vacuum System [ 8675 ]. The regenerate leaves the second adsorber [ 8625 B] as a vapor stream. It is cooled in a VOC Condenser [ 8650 ] supplied with a cooling water supply [ 470 ] and a cooling water return [ 472 ]. Condensed VOC regenerate product is withdrawn along stream through VOC Separation System Control Volume VOC Discharge [VOC-OUT].
[0199] A VOC vacuum system transfer line [ 464 ] connects the VOC Vacuum System [ 8675 ], with the VOC Condenser [ 8650 ]. The Vacuum system is preferably a liquid ring vacuum pump that uses a liquid VOC seal fluid [ 466 ] within its pump casing (not shown).
[0200] This system is preferably operated during adsorption at a pressure of 25 psia of greater and preferably 300 psia of greater. The VPSA system during regeneration of the bed, in one embodiment, is operated at less than atmospheric pressure. In one embodiment, the VPSA system is operated at a pressure of 7.5 psia or less and preferably 5 psia or less to regenerate the bed. In one embodiment, the VPSA system uses a two bed system. Optionally a three bed system is used. In another embodiment, four or more beds are used.
Sequence Step I, Option 2
[0201] In another non-limiting embodiment, VOC may be removed from syngas by utilization of a continuous pressurized fluidized particulate bed adsorption system whereby VOC laden syngas is used to fluidize a particulate bed containing an adsorption medium that selectively adsorbs VOC.
[0202] FIG. 19 depicts, Sequence Step I, VOC Removal [I], Option 2 as the embodiment situated within VOC Removal Control Volume [I- 1 ]. An Aromatic Hydrocarbon Fluidized Sorption Bed [ 8700 ] accepts VOC laden syngas from stream [I-IN] and outputs a VOC-depleted syngas through stream [I-OUT].
[0203] VOC laden syngas is introduced into the Aromatic Hydrocarbon Fluidized Sorption Bed [ 8700 ] through a distribution plate [ 474 ], which may be positioned below an optional support grid system [ 476 ] with a suitable screen to prevent reverse-flow of absorbent into the inlet conduit [I-IN].
[0204] Syngas fluidizes the adsorbent bed material [ 478 ] which adsorbs VOC from the vapor bubbles [ 480 ] passing up through the bed. An optional internal cyclone [ 482 ] may be positioned within the freeboard section [ 484 ] of the fluidized bed to separate the adsorbent from the VOC-depleted syngas, and return the adsorbent to the bed via a cyclone dipleg [ 486 ].
[0205] Desorption of VOC from the VOC saturated adsorbent takes place within the indirectly heated Regen Heat Exchange Fluidized Bed [ 8725 ]. In order for the Aromatic Hydrocarbon Fluidized Sorption Bed [ 8700 ] to realize a continuous separation of VOC from syngas, adsorbent bed material [ 478 ] must be moved from the bed, regenerated, and then transported back to the bed. A series of alternating solids handling valves [ 490 a & 490 b ], configured in a lock hopper arrangement, may be used to batch-transfer volumes of adsorbent bed material [ 478 ] through VOC adsorbent transfer conduit [ 488 ] to the Regen Heat Exchange Fluidized Bed [ 8725 ]. Lock hopper valve arrangements are well known in the art to which it pertains and are commonly used to transfer solids from one isolated pressurized environment to another.
[0206] Sequence Step I, VOC Removal [I], Option 2 is preferentially installed prior to Syngas Compression Sequence Step [H]. Therefore, the preferred operating pressure range for the Aromatic Hydrocarbon Fluidized Sorption Bed [ 8700 ] of Sequence Step I, Option 2 ranges from 30 to 75 psia. The regenerate product line [ 430 ] connected to the Regen Heat Exchange Fluidized Bed [ 8725 ] is held under vacuum conditions as described in FIG. 18 . The Regen Heat Exchange Fluidized Bed [ 8725 ] is operated under vacuum conditions at a pressure 14.5 psia or less and preferably 8.5 psia or less.
[0207] The Regen Heat Exchange Fluidized Bed [ 8725 ] is continuously fluidized with a VOC-depleted vapor source [ 492 ], preferably with FT tailgas, however, steam, compressed syngas, or any other available vapor, such as nitrogen or air may be used instead.
[0208] The VOC-depleted vapor source [ 492 ] is introduced into the Regen Heat Exchange Fluidized Bed [ 8725 ] through a distribution plate [ 494 ], which may be positioned below an optional support grid system [ 496 ] with a suitable screen. A heat source [ 498 ], preferably steam, is made available to at least one heat transfer chamber [ 500 ] that shares at least one heat transfer surface [ 502 ] with that of the fluidized adsorbent bed material [ 478 ] contained within the Regen Heat Exchange Fluidized Bed [ 8725 ]. This allows thermal energy to be indirectly transferred into the bed to allow a temperature aided desorption of VOC from the pores of the adsorbent material that is fluidized with the VOC-depleted vapor source [ 492 ]. VOC will be released from the adsorbent material within the bed and will enter the vapor bubbles [ 504 ] as they pass up through the bed.
[0209] An optional internal cyclone [ 508 ] may be positioned within the freeboard section [ 512 ] of the fluidized bed to separate the adsorbent from the VOC laden vapor, and return the adsorbent to the bed via a cyclone dipleg [ 514 ]. A series of alternating solids handling valves [ 516 a & 516 b ], configured in a lock hopper arrangement, may be used to batch-transfer volumes of regenerated adsorbent bed material [ 478 ] through transfer conduit [ 518 ] to the Sorbent Transfer Tank [ 8750 ].
[0210] The Sorbent Transfer Tank [ 8750 ] is a cylindrical pressure vessel equipped with a dip tube [ 520 ], pressurized vapor source [ 522 ], and solids handling valves [ 524 a & 524 b ], which are used together in combination to transport regenerated adsorbent bed material [ 478 ] back to the Aromatic Hydrocarbon Fluidized Sorption Bed [ 8700 ] through regen adsorbent transport line [ 526 ]. Regenerated adsorbent bed material [ 478 ] is first transferred from the Regen Heat Exchange Fluidized Bed [ 8725 ] to the Sorbent Transfer Tank [ 8750 ] through solids handling valves [ 516 a & 516 b ]. The Sorbent Transfer Tank [ 8750 ] is the isolated and pressurized with the vapor source [ 522 ] by opening solids handling valve [ 524 a ] while valve 524 b is closed. When the pressure in the Sorbent Transfer Tank [ 8750 ] exceeds that of the Aromatic Hydrocarbon Fluidized Sorption Bed [ 8700 ], the valve positions of solids handling valves [ 524 a & 524 b ] are switched allowing regenerated adsorbent bed material [ 478 ] to be conveyed via a pressure surge from the Sorbent Transfer Tank [ 8750 ] up through the dip tube [ 520 ], and through the regen adsorbent transport line [ 526 ], where it may then enter the Aromatic Hydrocarbon Fluidized Sorption Bed [ 8700 ]. The regenerated adsorbent bed material [ 478 ] may either free fall through the freeboard section [ 484 ], or if perforated trays [ 528 ] are installed in the freeboard section [ 484 ], the regenerated adsorbent bed material [ 478 ] may gradually trickle down through the vessel and thus improve gas to solid contact.
[0211] In another non-limiting embodiment, the Regen Heat Exchange Fluidized Bed [ 8725 ] may be operated under positive pressure conditions wherein VOC may be condensed and recovered as disclosed in FIG. 18 . In this particular embodiment, a VOC laden gaseous hydrocarbon vapor [ 430 ] may then exit the Regen Heat Exchange Fluidized Bed [ 8725 ], where it then may be made available as a fuel source to the Hydrocarbon Reformer [ 8000 ] of Sequence Step B, Hydrocarbon Reforming [B].
Sequence Step J, Metal Removal
[0212] FIG. 20 depicts Sequence Step J, Metal Removal [J], wherein Metal Removal Control Volume [J- 1 ] accepts a metal laden Sequence Step J Syngas Inlet [J-IN], and outputs a metal depleted Sequence Step J Syngas Discharge [J-OUT].
[0213] Metal Guard Bed [ 8775 ] is preferably comprised of vertical cylindrical pressure vessel containing cellulose acetate packing media possessing an affinity to sorb heavy metals, not only including, mercury, arsenic, lead, and cadmium. The cellulose acetate may be in the form of beads, spheres, flake, or pellets. Alternatively, sorbents such as Mersorb, from NUCON International, Inc., or AxTrap 277 from Axens—IFP Group Technologies, or the like, may be used.
Sequence Step K, Ammonia Removal [K]
[0214] FIG. 21 depicts Sequence Step K, Ammonia Removal [K], wherein Ammonia Removal Control Volume [K- 1 ] accepts an ammonia laden Sequence Step K Syngas Inlet [K-IN], and outputs an ammonia-depleted Sequence Step K Syngas Discharge [K-OUT].
[0215] The Ammonia Scrubber [ 8800 ], configured similar to the Chlorine Scrubber [ 8500 ], is also a vertically oriented cylindrical, or rectangular, pressure vessel having a lower section, and an upper section, along with a central section that contains a specified quantity of packed absorption media, which is supported upon a suitable support grid system commonplace to industrial chemical equipment systems. The upper section of the scrubber preferably contains a demister that is positioned above a scrubber spray nozzle system [ 736 ] which introduces the scrubbing absorption liquid to the scrubber.
[0216] The purpose of the Ammonia Scrubber is to remove trace amounts of nitrogenated compounds including ammonia and hydrogen cyanide from the syngas by using water as the main scrubbing absorption liquid.
[0217] Syngas enters the lower section of the Ammonia Scrubber and passes up through the scrubber's central section where the syngas vapor comes into intimate contact with the water scrubbing liquid traveling countercurrently via gravity flow down through the scrubber's packing. A level control loop, comprising a level transmitter [ 700 ], positioned on the lower section of the scrubber, and a level control valve [ 702 ], may be automatically operated to permit water to be bled from the scrubber water recirculation piping [ 738 ], via a waste water transfer conduit [ 740 ], to maintain a steady liquid level within the lower section of the scrubber. A scrubber water recirculation pump [ 776 ], accepts water from the lower section of the scrubber, through the pump suction piping [ 742 ], and transfers the water through the scrubber's spray nozzle system [ 736 ] and into the upper section of the scrubber where the flow of liquid is directed downwards onto the scrubber central packing. Process water [ 714 ] may be transferred to the scrubber water recirculation piping, or the lower section of the scrubber.
Sequence Step L, Ammonia Polishing [L]
[0218] FIG. 22 depicts Sequence Step L, Ammonia Polishing [L], wherein Ammonia Polishing Control Volume [L- 1 ] accepts a Sequence Step L Syngas Inlet [L-IN], and outputs a Sequence Step L Syngas Discharge [L-OUT].
[0219] The Ammonia Guard Bed [ 8825 ] is comprised of preferably a vertical cylindrical pressure vessel containing molecular sieve type 4A which possess an affinity to sorb trace amounts of nitrogenated compounds including ammonia and hydrogen cyanide. Alternatively, sorbents such 5A, 13×, dealuminated faujasite, dealuminated pentasil, and clinoptilolite, or the like, may be used.
Sequence Step M, Heat Addition [M]
[0220] FIG. 23 depicts Sequence Step M, Heat Addition [M], wherein Heat Addition Control Volume [M- 1 ] accepts a Sequence Step M Syngas Inlet [M-IN], and outputs a Sequence Step M Syngas Discharge [M-OUT].
[0221] The Heat Exchanger [ 8850 ] is preferably of a shell- and tube type, where syngas is routed to the tube-side. Steam located on the shell-side of the exchanger elevates the temperature of the syngas from between 75 to 125 degrees F. to between 350 and 450 degrees Fahrenheit.
[0222] The Heat Exchanger [ 8850 ] is equipped with a heat source [ 780 ] and a heat discharge [ 782 ] that communicate with the shell-side to indirectly transfer heat to the syngas. Alternately, the heater may be electrically driven, or flue gas or another alternate heat source may be utilized in the place of steam to increase the temperature of the syngas.
Sequence Step N, Carbonyl Sulfide Removal [N]
[0223] FIG. 24 depicts Sequence Step N, Carbonyl Sulfide Removal [N], wherein Carbonyl Sulfide Removal Control Volume [N- 1 ] accepts a carbonyl sulfide laden Sequence Step N Syngas Inlet [N-IN], and outputs a sulfur-depleted Sequence Step N Syngas Discharge [N-OUT].
[0224] The Carbonyl Sulfide Hydrolysis Bed [ 8875 ] is comprised of preferably a vertical cylindrical pressure vessel containing a packed bed media, comprised of alumina or titania, either in the form of beads, pellets, granules, spheres, packing, or the like and serves the purpose to hydrolyze carbonyl sulfide into hydrogen sulfide and carbon dioxide prior to the hydrogen sulfide polishing step. Water [ 790 ] in the form of steam may be injected into the hydrolysis bed aide the carbonyl sulfide to react with water to hydrolyze into hydrogen sulfide and carbon dioxide over the packed bed media. It is preferred to accomplish the goals of this sequence step with the utilization of a packed bed of an alumina based material which allows for the hydrolysis of carbonyl sulfide into carbon dioxide and hydrogen sulfide, however any type of carbonyl sulfide removal system or method, such as adsorption or absorption type systems, may be employed to accomplish the goal of the sequence step to remove carbonyl sulfide from syngas.
Sequence Step O, Sulfur Polishing [O]
[0225] FIG. 25 depicts Sequence Step O, Sulfur Polishing [O], wherein Sulfur Polishing Control Volume [O- 1 ] accepts Sequence Step O Syngas Inlet [O-IN], and outputs Sequence Step 0 Syngas Discharge [O-OUT].
[0226] The Sulfur Guard Bed [ 8900 ] is comprised of preferably a vertical cylindrical pressure vessel containing a sorbent media, comprised of zinc oxide in the form of beads, pellets, granules, spheres, packing, or the like and serves the purpose to adsorb trace amounts of hydrogen sulfide and elemental sulfur.
Sequence Step P, Carbon Dioxide Removal [P]
[0227] FIG. 26 depicts Sequence Step P, Carbon Dioxide Removal [P], wherein Carbon Dioxide Removal Control Volume [P- 1 ] accepts a carbon dioxide laden Sequence Step P Syngas Inlet [P-IN], and outputs a carbon dioxide depleted Sequence Step P Syngas Discharge [P-OUT]. The Heat Exchange CO2 Separator serves the purpose to remove the carbon dioxide from the pressurized syngas and recycle it for utilization somewhere else. It is preferred to recycle the separated carbon dioxide as an oxidant within the Hydrocarbon Reformer [ 8000 ], or for use in the upstream syngas generation process as a fluidization medium, or as vapor purges on instrumentation and sampling ports and connections.
[0228] The equipment functionality as described above in Sequence Step I, Option 1 , of FIG. 18 is identical to that of the preferred embodiment situated within Dioxide Removal Control Volume [Q- 1 ] of Sequence Step P, Carbon Dioxide Removal [P]. However, one main difference exists in that the Heat Exchange CO2 Separator [ 8925 A&B] is preferentially comprised of a shell and tube heat exchanger, preferably equipped with ½″ diameter tubes. It is preferred to dispose an activated carbon fiber material, preferably in the form of spiral wound activated carbon fiber fabric, or braided activated carbon fiber cloth strands, within the tube side particulate bed [ 810 ] of the vessel while the shell-side thermal transfer chamber [ 804 ] runs empty except when undergoing a regeneration cycle.
[0229] The regeneration process as described above in Sequence Step I, Option 1 , of FIG. 18 is identical to that of the preferred embodiment situated within Dioxide Removal Control Volume [P- 1 ] of Sequence Step P, Carbon Dioxide Removal [P], except for the fact that the Sequence Step P does not utilize a vacuum system. Instead, the regenerate product line [ 830 ] is in communication with a Carbon Dioxide Accumulator [ 8950 ]. The purpose of the Carbon Dioxide Accumulator [ 8950 ] is to provide sufficient volume and residence time for regenerated carbon dioxide laden syngas vapors, transferred from a regeneration cycle, to be stored for utilization somewhere else by transferring the carbon dioxide through a Sequence Step P Carbon Dioxide Discharge [CO2-OUT]. The accumulator operates at a pressure of 100 to 165 psia.
[0230] Alternatively, a membrane or sorption based carbon dioxide recovery unit may be used to accomplish the goals of carbon dioxide removal and recovery defined by Sequence Step P, Carbon Dioxide Removal [P]. In a further embodiment, carbon dioxide may be reduced within this sequence step by use of a carbon dioxide electrolyzer.
Sequence Step Q, R, S: Heat Addition [Q]; Steam Methane Reforming [R]; Heat Removal [ 5 ]
[0231] With reference to FIG. 27 , Sequence Step Q, Heat Addition [Q], Sequence Step R, Steam Methane Reforming [R], and Sequence Step S, Heat Removal [S] are combined in a preferred fashion as to realize an energy integrated system capable of reforming hydrocarbons present in the inlet syngas source [P-IN]. This configuration is preferred when utilizing the optional gaseous hydrocarbon source [HC-IN] routed to the inlet of the Syngas Compressor [ 8600 ].
[0232] A Heat Exchanger [ 8975 ] accepts a gaseous hydrocarbon laden syngas Sequence Step Q Syngas Inlet [Q-IN] and elevates its temperature to the operating temperature of the Steam Methane Reformer [ 9000 ]. This is accomplished by utilization of heat transfer integration with the reformed cleaned and conditioned syngas [R-OUT] transferred a the shared heat transfer surface within the Heat Exchanger [ 8975 ]. An oxidant source [ 850 ] is made available to the Steam Methane Reformer [ 9000 ] to ensure complete decomposition of the gaseous hydrocarbons into carbon monoxide and hydrogen. A cooled syngas depleted of undesirable gaseous hydrocarbons [S-OUT] is discharged from the Heat Exchanger [ 8975 ] to be made available to a downstream syngas processing technology.
Syngas Processing Embodiments
[0233] Those of ordinary skill in the art will recognize that fewer that all of the steps B-S of FIG. 1 may be used in a given syngas processing method and system.
[0234] For instance, in a first syngas processing method, only steps C, D, G, H, K, O and T may be practiced, and the corresponding system will include the equipment required to implement these steps.
[0235] In a second syngas processing method, only steps B, C, D, F, G, H, I, K, M, N, O and T may be practiced, and the corresponding system will include the equipment required to implement these steps.
[0236] FIGS. 30A-30F present a number of syngas processing embodiments that one might wish to implement. Each row of the table in FIGS. 30A-30F presents the steps to be practiced in a single syngas processing embodiment. It is understood that the corresponding elements necessary to realize each such method would be needed in a system for that embodiment. method.
EQUIPMENT LIST
[0237] The following list of equipment presents items that should be understandable to those of ordinary skill in the art familiar of syngas processing.
8000 Hydrocarbon Reformer 8025 Heat Recovery Steam Generator (HRSG) Superheater 8050 Heat Recovery Steam Generator (HRSG) 8075 Steam Drum 8100 Venturi Scrubber 8125 Char Scrubber 8150 Char Scrubber Heat Exchanger 8175 Continuous Candle Filter Decanter 8200 Filtrate Backflush Buffer Tank 8225 Filter Cake Liquid Removal System 8250 Liquid Depleted Solids Collection 8275 Decanter 8300 Continuous Candle Filter 8325 SVOC Flash Tank Heat Exchanger 8350 SVOC Flash Tank 8375 Solvent Cooler 8400 SVOC Condenser 8425 SVOC Vacuum System 8450 Guard Filter 8475 SVOC Sorptive Separator 8500 Chlorine Scrubber 8525 Chlorine Scrubber Heat Exchanger 8550 Sulfur Scrubber 8575 Particulate Filter 8600 Syngas Compressor 8625 Aromatic Hydrocarbon Micro-Scale Heat Exchange Adsorber 8650 VOC Condenser 8675 VOC Vacuum System 8700 Aromatic Hydrocarbon Fluidized Sorption Bed 8725 Regen Heat Exchange Fluidized Bed 8750 Sorbent Transfer Tank 8775 Metals Guard Bed 8800 Ammonia Scrubber 8825 Ammonia Guard Bed 8850 Heat Exchanger 8875 Carbonyl Sulfide Hydrolysis Bed 8900 Sulfur Guard Bed 8925 Heat Exchange CO2 Separator 8950 Carbon Dioxide Accumulator 8975 Heat Exchanger 9000 Steam Methane Reformer
LIST OF REFERENCE NUMERALS
[0000]
Sequence Step B Syngas Inlet [B-IN]
Sequence Step B Syngas Discharge [B-OUT]
Sequence Step C Syngas Inlet [C-IN]
Sequence Step C Syngas Discharge [C-OUT]
Sequence Step D Syngas Inlet [D-IN]
Sequence Step D Syngas Discharge [D-OUT]
SVOC Separation System Control Volume SVOC Discharge [SVOC-OUT]
Sequence Step E Syngas Inlet [E-IN]
Sequence Step E Syngas Discharge [E-OUT]
Sequence Step F Syngas Inlet [F-IN]
Sequence Step F Syngas Discharge [F-OUT]
Sequence Step G Syngas Inlet [G-IN]
Sequence Step G Syngas Discharge [G-OUT]
optional gaseous hydrocarbon source [HC-IN]
Sequence Step H Syngas Inlet [H-IN]
Sequence Step H Syngas Discharge [H-OUT]
Sequence Step I Syngas Inlet [I-IN]
VOC Separation System Control Volume VOC Discharge [VOC-OUT]
Sequence Step I Syngas Discharge [I-OUT]
Sequence Step J Syngas Inlet [J-IN]
Sequence Step J Syngas Discharge [J-OUT]
Sequence Step K Syngas Inlet [K-IN]
Sequence Step K Syngas Discharge [K-OUT]
Sequence Step L Syngas Inlet [L-IN]
Sequence Step L Syngas Discharge [L-OUT]
Sequence Step M Syngas Inlet [M-IN]
Sequence Step M Syngas Discharge [M-OUT]
Sequence Step N Syngas Inlet [N-IN]
Sequence Step N Syngas Discharge [N-OUT]
Sequence Step O Syngas Inlet [O-IN]
Sequence Step O Syngas Discharge [O-OUT]
Sequence Step P Syngas Inlet [P-IN]
Sequence Step P Syngas Discharge [P-OUT]
Sequence Step P Carbon Dioxide Discharge [CO2-OUT]
Sequence Step Q Syngas Inlet [Q-IN]
Sequence Step Q Syngas Discharge [Q-OUT]
Sequence Step R Syngas Inlet [R-IN]
Sequence Step R Syngas Discharge [R-OUT]
Sequence Step S Syngas Inlet [S-IN]
Sequence Step S Syngas Discharge [S-OUT]
Hydrocarbon Reforming Control Volume [B- 1 ]
Syngas Cooling Control Volume [C- 1 ]
Solids Removal & SVOC Removal Control Volume [D- 1 ]
Chlorine Removal Control Volume [E- 1 ]
Sulfur Removal Control Volume [F- 1 ]
Particulate Filtration Control Volume [G- 1 ]
VOC Removal Control Volume [I- 1 ]
Metal Removal Control Volume [J- 1 ]
Ammonia Removal Control Volume [K- 1 ]
Ammonia Polishing Control Volume [L- 1 ]
Heat Addition Control Volume [M- 1 ]
Carbonyl Sulfide Removal Control Volume [N- 1 ]
Sulfur Polishing Control Volume [O- 1 ]
Carbon Dioxide Removal Control Volume [P- 1 ]
SVOC Separation System Control Volume [SVOC- 1 ]
additives [ 2 ]
oxidant source[ 4 ]
gaseous hydrocarbon source [ 6 ]
superheated steam [ 8 ]
HRSG transfer line [ 10 ]
water [ 12 ]
steam and water mixture [ 14 ]
pressure transmitter [ 16 ]
pressure control valve [ 18 ]
saturated steam transfer line [ 20 ]
level transmitter [ 22 ]
level control valve [ 24 ]
water supply line [ 26 ]
steam drum continuous blowdown line [ 28 ]
Venturi Scrubber recirculation water line [ 30 ]
Venturi Scrubber recirculation solvent line [ 32 ]
Venturi Scrubber to Char Scrubber transfer conduit [ 34 ]
scrubber spray nozzle system [ 36 ]
Char Scrubber recirculation water [ 38 ]
Char Scrubber recirculation solvent [ 40 ]
Char Scrubber underflow downcomer [ 42 ]
common water recirculation line [ 44 ]
cooling water supply [ 46 ]
cooling water return [ 48 ]
upright tank [ 50 ]
central section [ 52 ]
closed dome shaped top [ 54 ]
conical lower sections [ 56 a & 56 b]
drain valve [ 58 a & 58 b]
drain line [ 60 a & 60 b]
vertical underflow weir [ 62 ]
upright vertical housing wall [ 64 ]
annular passageway [ 66 ]
common water header [ 68 ]
water take-off nozzles [ 70 a & 70 b]
water recirculation pump [ 72 ]
inner solvent chamber [ 74 ]
solvent and water interface rag-layer [ 78 ]
filter bundles [ 80 a & 80 b]
candle filter elements [ 82 ]
filter bundle common register [ 84 a & 84 b]
filtrate removal conduit [ 86 a & 86 b]
filtrate process pump [ 88 ]
common filtrate suction header [ 90 ]
filtrate register valve [ 92 a & 92 b]
filtrate solvent transfer line [ 94 ]
alternate backflush transfer line [ 95 ]
common solvent recirculation line [ 96 ]
pressure transmitters [ 98 a & 98 b]
housing pressure transmitter [ 100 ]
flow indicating sight glasses [ 102 a & 102 b]
SVOC-depleted solvent transfer line [ 104 ]
level transmitter [ 106 ]
solvent supply level control valve [ 108 ]
solvent supply line [ 110 ]
solvent backflush pump [ 112 ]
filtrate transfer conduit [ 114 ]
backflush tank recirculation line [ 116 ]
restriction orifice [ 118 ]
backflush filtrate regen valves [ 120 a & 120 b]
filtrate backflush regen conduit [ 122 a & 122 b]
liquid removed from the filter cake [ 124 ]
waste water header [ 126 ]
solids & SVOC laden solvent filtrate transfer line [ 128 ]
SVOC laden solvent filtrate transfer line [ 130 ]
alternate backflush transfer line [ 131 ]
steam inlet line [ 132 ]
steam discharge line [ 134 ]
SVOC laden filtrate solvent Flash Tank transfer line [ 136 ]
pressure letdown device [ 138 ]
SVOC flash transfer conduit [ 140 ]
SVOC-depleted solvent transfer line [ 142 ]
SVOC-depleted solvent transfer pump [ 144 ]
solvent transfer line [ 146 ]
solvent recycle line [ 148 ]
cooling water supply [ 150 ]
cooling water return [ 152 ]
impingement baffle [ 154 ]
spray nozzles [ 156 ]
CIP agent transfer line [ 158 ]
CIP agent isolation valve [ 160 ]
cooled SVOC-depleted solvent transfer line [ 162 ]
SVOC vacuum system transfer line [ 164 ]
liquid SVOC seal fluid [ 166 ]
vacuum system vent line [ 168 ]
cooling water supply [ 170 ]
cooling water return [ 172 ]
porous membrane [ 174 ]
porous chemical resistant coating [ 176 ]
SVOC laden solvent membrane process surface [ 178 a]
SVOC permeate membrane process surface [ 178 b]
filtrate solvent transfer line [ 180 ]
level transmitter [ 200 ]
level control valve [ 202 ]
process water [ 214 ]
scrubber spray nozzle system [ 236 ]
scrubber water recirculation piping [ 238 ]
water transfer conduit [ 240 ]
pump suction piping [ 242 ]
cooling water supply [ 246 ]
cooling water return [ 248 ]
recirculation pump [ 276 ]
level transmitter [ 300 ]
level control valve [ 302 ]
process water [ 314 ]
sulfur scavenger derived solution [ 316 ]
scrubber spray nozzle system [ 336 ]
scrubber water recirculation piping [ 338 ]
water transfer conduit [ 340 ]
pump suction piping [ 342 ]
recirculation pump [ 376 ]
adsorption chamber [ 402 ]
thermal transfer chamber [ 404 ]
feed inlet [ 406 a & 406 b]
product outlet [ 408 a & 408 b]
particulate bed [ 410 ]
thermal transfer chamber inlet valve [ 412 a & 412 b]
inlet valve [ 414 a & 414 b]
product outlet valve [ 416 a & 416 b]
purge inlet valve [ 418 a & 418 b]
depressurization valve [ 420 a & 420 b]
modulating purge valve [ 422 ]
regenerate product line [ 430 ]
VOC vacuum system transfer line [ 464 ]
liquid VOC seal fluid [ 466 ]
vacuum system vent line [ 468 ]
cooling water supply [ 470 ]
cooling water return [ 472 ]
distribution plate [ 474 ]
support grid system [ 476 ]
adsorbent bed material [ 478 ]
vapor bubbles [ 480 ]
internal cyclone [ 482 ]
freeboard section [ 484 ]
cyclone dipleg [ 486 ]
VOC adsorbent transfer conduit [ 488 ]
solids handling valves [ 490 a & 490 b]
VOC-depleted vapor source [ 492 ]
distribution plate [ 494 ]
support grid system [ 496 ]
heat source [ 498 ]
heat transfer chamber [ 500 ]
heat transfer surface [ 502 ]
vapor bubbles [ 504 ]
gaseous hydrocarbon vapor [ 506 ]
internal cyclone [ 508 ]
freeboard section [ 512 ]
cyclone dipleg [ 514 ]
solids handling valves [ 516 a & 516 b]
transfer conduit [ 518 ]
dip tube [ 520 ]
vapor source [ 522 ]
solids handling valves [ 524 a & 524 b]
regen adsorbent transport line [ 526 ]
perforated trays [ 528 ]
level transmitter [ 700 ]
level control valve [ 702 ]
process water [ 714 ]
scrubber spray nozzle system [ 736 ]
scrubber water recirculation piping [ 738 ]
water transfer conduit [ 740 ]
pump suction piping [ 742 ]
recirculation pump [ 776 ]
heat source [ 780 ]
heat discharge [ 782 ]
water [ 790 ]
adsorption chamber [ 802 ]
thermal transfer chamber [ 804 ]
feed inlet [ 806 a & 806 b]
product outlet [ 808 a & 808 b]
particulate bed [ 810 ]
thermal transfer chamber inlet valve [ 812 a & 812 b]
inlet valve [ 814 a & 814 b]
product outlet valve [ 816 a & 816 b]
purge inlet valve [ 818 a & 818 b]
depressurization valve [ 820 a & 820 b]
modulating purge valve [ 822 ]
regenerate product line [ 830 ]
oxidant source [ 850 ]
SEQUENCE STEP LIST
[0000]
Syngas Generation [A]
Sequence Step B, Hydrocarbon Reforming [B]
Sequence Step C, Syngas Cooling [C]
Sequence Step D, Solids Removal & SVOC Removal [D]
Sequence Step E, Chlorine Removal [E]
Sequence Step F, Sulfur Removal [F]
Sequence Step G, Particulate Filtration [G]
Sequence Step H, Syngas Compression [H]
Sequence Step I, VOC Removal [I]
Sequence Step J, Metal Removal [J]
Sequence Step K, Ammonia Removal [K]
Sequence Step L, Ammonia Polishing [L]
Sequence Step M, Heat Addition [M]
Sequence Step N, Carbonyl Sulfide Removal [N]
Sequence Step O, Sulfur Polishing [O]
Sequence Step P, Carbon Dioxide Removal [P]
Sequence Step Q, Heat Addition [Q]
Sequence Step R, Steam Methane Reforming [R]
Sequence Step S, Heat Removal [ 5 ]
Clean Syngas For End User [T]
Sequence Step B Syngas Inlet [B-IN]
Sequence Step B Syngas Discharge [B-OUT]
Sequence Step C Syngas Inlet [C-IN]
Sequence Step C Syngas Discharge [C-OUT]
Sequence Step D Syngas Inlet [D-IN]
Sequence Step D Syngas Discharge [D-OUT]
SVOC Separation System Control Volume SVOC Discharge [SVOC-OUT]
Sequence Step E Syngas Inlet [E-IN]
Sequence Step E Syngas Discharge [E-OUT]
Sequence Step F Syngas Inlet [F-IN]
Sequence Step F Syngas Discharge [F-OUT]
Sequence Step G Syngas Inlet [G-IN]
Sequence Step G Syngas Discharge [G-OUT]
optional gaesous hydrocarbon source [HC-IN]
Sequence Step H Syngas Inlet [H-IN]
Sequence Step H Syngas Discharge [H-OUT]
Sequence Step I Syngas Inlet [I-IN]
VOC Separation System Control Volume VOC Discharge [VOC-OUT]
Sequence Step I Syngas Discharge [I-OUT]
Sequence Step J Syngas Inlet [J-IN]
Sequence Step J Syngas Discharge [J-OUT]
Sequence Step K Syngas Inlet [K-IN]
Sequence Step K Syngas Discharge [K-OUT]
Sequence Step L Syngas Inlet [L-IN]
Sequence Step L Syngas Discharge [L-OUT]
Sequence Step M Syngas Inlet [M-IN]
Sequence Step M Syngas Discharge [M-OUT]
Sequence Step N Syngas Inlet [N-IN]
Sequence Step N Syngas Discharge [N-OUT]
Sequence Step O Syngas Inlet [O-IN]
Sequence Step O Syngas Discharge [O-OUT]
Sequence Step P Syngas Inlet [P-IN]
Sequence Step P Syngas Discharge [P-OUT]
Sequence Step P Carbon Dioxide Discharge [CO2-OUT]
Sequence Step Q Syngas Inlet [Q-IN]
Sequence Step Q Syngas Discharge [Q-OUT]
Sequence Step R Syngas Inlet [R-IN]
Sequence Step R Syngas Discharge [R-OUT]
Sequence Step S Syngas Inlet [S-IN]
Sequence Step S Syngas Discharge [S-OUT]
Hydrocarbon Reforming Control Volume [B- 1 ]
Syngas Cooling Control Volume [C- 1 ]
Solids Removal & SVOC Removal Control Volume [D- 1 ]
Chlorine Removal Control Volume [E- 1 ]
Sulfur Removal Control Volume [F- 1 ]
Particulate Filtration Control Volume [G- 1 ]
VOC Removal Control Volume [I- 1 ]
Metal Removal Control Volume [J- 1 ]
Ammonia Removal Control Volume [K- 1 ]
Ammonia Polishing Control Volume [L- 1 ]
Heat Addition Control Volume [M- 1 ]
Carbonyl Sulfide Removal Control Volume [N- 1 ]
Sulfur Polishing Control Volume [O- 1 ]
Carbon Dioxide Removal Control Volume [P- 1 ]
SVOC Separation System Control Volume [SVOC- 1 ]
filtration [step 950 ]
filter bundle isolation [step 952 ]
filtrate backflush [step 954 ]
filter cake sedimentation [step 956 ]
filter cake discharge start [step 958 ]
filter cake discharge end [step 960 ]
filtration restart preparation [step 962 ]
Step D 1 a
Step D 1 b
Step D 1 c
Step D 1 ca
Step D 1 cb
Step D 1 d
Step D 1 e
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A system and method for processing unconditioned syngas first removes solids and semi-volatile organic compounds (SVOC), then removes volatile organic compounds (VOC), and then removes at least one sulfur containing compound from the syngas. Additional processing may be performed depending on such factors as the source of syngas being processed, the products, byproducts and intermediate products desired to be formed, captured or recycled and environmental considerations.
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FIELD OF THE INVENTION
[0001] The present invention relates generally to aviation fuel and a blending stock for aviation fuel. More particularly, it relates to an aviation fuel or fuel component which is derived from a non-petroleum feedstock.
BACKGROUND OF THE INVENTION
[0002] Distillate fuels produced from non-petroleum sources and derived largely from the Fischer Tropsch (FT) process are typically highly paraffinic and have excellent burning properties and very low sulphur content. This makes them highly suitable as a fuel source where environmental concerns are important; and in circumstances where the security of supply and availability of petroleum supplies may cause concern.
[0003] However, although many physical properties for conventional distillate fuels can be matched and even outperformed, the fuels derived from FT processes and the like can not provide conventional jet fuel “drop-in compatibility” (i.e. be amenable to direct substitution within the conventional petroleum-derived jet fuel infrastructure), as they lack some of the major hydrocarbon constituents of typical petroleum-derived kerosene fuel. For example, due to their low aromatic content, FT jet fuels tend not to comply with certain industry jet fuel specified characteristics such as minimum density, seal swell propensity and lubricity.
[0004] This difficulty in obtaining suitable jet fuel entirely from non-petroleum feedstocks has triggered several developments in the downstream processing of feedstock in order to obtain suitable products.
[0005] For example, U.S. Pat. No. 4,645,585 teaches the production of novel fuels, including jet fuel components, from the extensive hydroprocessing of highly aromatic heavy oils such as those derived from coal pyrolysis and coal hydrogenation.
[0006] WO 2005/001002 relates to a distillate fuel comprising a stable, low-sulphur, highly paraffinic, moderately unsaturated distillate fuel blendstock. The highly paraffinic, moderately unsaturated distillate fuel blendstock is prepared from an FT-derived product that is hydroprocessed under conditions during which a moderate amount of unsaturates are formed or retained to improve stability of the product.
[0007] U.S. Pat. No. 6,890,423 teaches the production of a fully synthetic jet fuel produced from an FT feedstock. The seal swell and lubricity characteristics of the base FT distillate fuel are adjusted through the addition of alkylaromatics and alkylcycloparaffins that are produced via the catalytic reforming of FT product. This process can result in a suitable aviation fuel generated entirely from a non-petroleum source, but the additional reforming steps required to generate the alkylaromatics and alkylcycloparaffins impart significant additional cost and complexity to the process.
[0008] US2009/0000185 teaches a method for producing a jet fuel from two independent blendstocks, where at least one blendstock is derived from a non-petroleum derived feedstock, which may be an FT source. In one form of the described method, the second blendstock is also produced via a non-petroleum source, such as via the pyrolysis or liquefaction of coal. However, the provision of at least two independent synthetic feedstocks is highly problematic and less likely to be cost effective when contrasted with petroleum-based fuel sources.
[0009] Accordingly, there remains a strong need for a fully-synthetic (i.e. non-petroleum sourced) aviation fuel and an economical means of producing it.
SUMMARY OF INVENTION
[0010] A fully synthetic aviation fuel or aviation fuel component having:
a total naphthenic content of more than 30 mass % a mass ratio of naphthenic to iso-paraffinic hydrocarbon species of more than 1 and less than 15 a density (at 15° C.) of greater than 0.775 g·cm −3 , but less than 0.850 g·cm −3 an aromatic hydrocarbon content of greater than 8 mass %, but less than 20 mass % a freezing point of less than −47° C. a lubricity BOCLE WSD value of less than 0.85 mm
[0017] The fully synthetic aviation fuel or aviation fuel component may have a mass ratio of naphthenic to aromatic hydrocarbons of from 2.5 to 4.5. Preferably, the mass ratio is between 3 and 4.
[0018] Preferably, the total naphthenic content of the synthetic aviation fuel or aviation fuel component is more than 35 mass %.
[0019] Preferably, the total naphthenic content of the synthetic aviation fuel or aviation fuel component is less than 60 mass %, and more preferably it is less than 50 mass %.
[0020] Preferably, the mass ratio of naphthenic to iso-paraffinic species of the synthetic aviation fuel or aviation fuel component is less than 10 and more preferably less than 5.
[0021] The aromatics content may be less than 18 mass % and more preferably less than 16 mass %.
[0022] Preferably the freezing point of the synthetic aviation fuels is less than −50° C., more preferably the freezing point is less than −53° C. and most preferably, the freezing point is less than −55° C.
[0023] The fully synthetic aviation fuel or fuel component is typically produced from a single non-petroleum source and comprises at least two blend components, where at least one component is produced from an LTFT process. The single source may be coal.
[0024] The fully synthetic aviation fuel or fuel component may have a freezing point that is lower than the freezing points of the blend components.
[0025] According to a second aspect of the invention, there is provided a fully synthetic coal-derived aviation fuel or aviation fuel component having a total naphthenic content of more than 30 mass %; a mass ratio of naphthenic to iso-paraffinic hydrocarbon species of more than 1 and less than 15; a density of greater than 0.775 g·cm −3 but less than 0.850 g·cm −3 ; an aromatic content of greater than 8 mass % but less than 20 mass %; a freezing point of less than −47° C. and a lubricity BOCLE WSD value of less than 0.85 mm including
a first LTFT-derived blend component comprising at least 95 mass % isoparaffins and normal paraffins and less, than 1 mass % aromatics; with a density (at 15° C.) of less than 0.775 g·cm −3 ; and a second tar-derived blend component comprising at least 60 mass % naphthenics, at least 10 mass % aromatics and at least 5 mass % isoparaffins and normal paraffins, with a density (at 15° C.) of more than 0.840 g·cm −3 ;
such that the first LTFT-derived blend component may comprise at least 20 volume % and preferably no more than 60 volume % of the blend.
[0028] The second tar-derived blend component is typically generated through the deliberate recovery of a tar fraction generated during gasification of a coal feedstock for syngas production. The tar-derived kerosene fraction may further comprise at least 70% by mass naphthenics.
[0029] In a preferred embodiment of the invention, the volume ratio of the first and second blend components is between 45:55 and 55:45.
[0030] According to a third aspect of the invention, there is provided a method of producing a coal-sourced, fully synthetic aviation fuel or aviation fuel component; including the steps of:
gasifying the coal under medium temperature conditions in a fixed bed gasifier such that a tar fraction can be recovered during the coal gasification step; and syngas for an LTFT reactor is produced; recovering from the LIFT reactor an LTFT syncrude; subjecting the tar fraction to hydroprocessing under hydroprocessing conditions to provide a tar-derived kerosene fraction having at least 60 mass % naphthenics; subjecting the LIFT syncrude to hydroprocessing under hydroprocessing conditions to provide a LTFT-derived kerosene fraction having at least 95 mass % isoparaffins and normal paraffins and less than 1 mass % aromatics; with a density (at 15° C.) of less than 0.775 g·cm −3 ; and blending the resultant tar-derived kerosene fraction and LIFT-derived kerosene fraction to obtain a fully synthetic aviation fuel or aviation fuel component.
[0036] The tar-derived kerosene fraction and the LTFT-derived kerosene fraction are blended in such a way that the LTFT-derived kerosene fraction may comprise at least 20 volume % and preferably no more than 60 volume % of the blend mixture. In a preferred embodiment of the invention, the ratio of the LTFT-derived kerosene and the tar-derived kerosene lies between 45:55 and 55:45.
[0037] The tar-derived kerosene fraction may be produced by a medium temperature coal gasification process (i.e. between 700 and 900° C.), for example by a Fixed Bed Dry Bottom (FBDB) (trade name) or fluidised bed coal gasification process. By employing a medium temperature process, a tar-derived kerosene component that contains both naphthenics and aromatics may be produced during the coal gasification step.
[0038] The hydrocarbon types of the tar-derived kerosene fraction will typically comprise between 60 and 80 mass % naphthenics. The hydrocarbon profile will typically further comprise between 15 and 30 mass % aromatics. The hydrocarbon type profile will typically further comprise between 5 and 15 mass % isoparaffins and normal paraffins.
[0039] In the specification, the terms “aromatics” and “aromatic hydrocarbons” are to have an equivalent meaning.
DETAILED DESCRIPTION OF THE INVENTION
[0040] According to the present invention, it has been found that it is possible to achieve a fully synthetic aviation fuel or fuel component that meets specific current conventional jet fuel requirements, (specifically density and aromatic content), through the suitable processing of a single synthetic fuel source.
[0041] This fuel is characterised in that it contains high levels of naphthenics or cycloparaffinic species relative to LTFT-derived kerosene fractions, which typically contain less than 1 mass % naphthenes.
[0042] Naphthenes typically form some component of petroleum-based aviation fuels (less than 30 mass %) and can contribute positively to certain required properties such as lowering the freezing point or enhancing seal swell propensity. They can however, contribute negatively to certain properties such as increased smoke point and viscosity. In addition, naphthenic species tend to be denser than paraffins with the same carbon number. Hence, the density of typical synthetic naphthenic-dominated kerosenes such as those generated by coal liquefaction and pyrolysis processes, will inevitably significantly, exceed the density requirements of aviation fuel specifications. Core to this invention therefore, is the development of a synthetic aviation fuel that capitalises on the positive properties of naphthenic species, whilst still meeting all the physical property requirements for aviation fuel, specifically density and smoke point.
[0043] This fuel can be produced using two parallel feedstock streams—one is generated via a conventional LTFT synthesis process; and the other is generated through the deliberate recovery of a tar fraction generated during medium temperature gasification of the coal feedstock for syngas production.
LTFT-Derived Kerosene Component
[0044] In this specification, reference is made to the Low Temperature Fischer-Tropsch (LTFT) process. This LTFT process is a well known process in which carbon monoxide and hydrogen are reacted over an iron, cobalt, nickel or ruthenium containing catalyst to produce a mixture of straight and branched chain hydrocarbon products ranging from methane to waxes and smaller amounts of oxygenates. This hydrocarbon synthesis process is based on the Fischer-Tropsch reaction:
[0000] 2H 2 +CO→˜[CH 2 ]˜+H 2 O
[0000] where ˜[CH 2 ]˜ is the basic building block of the hydrocarbon product molecules.
[0045] The LTFT process is therefore used industrially to convert synthesis gas, which may be derived from coal, natural gas, biomass or heavy oil streams, into hydrocarbons ranging from methane to species with molecular masses above 1400. While the term Gas-to-Liquid (GTL) process refers to schemes based on natural gas (i.e. predominantly methane) to obtain the synthesis gas, the quality of the synthetic products is essentially the same once the synthesis conditions and the product work-up are defined.
[0046] While the main products are typically linear paraffinic species, other species such as branched paraffins, olefins and oxygenated components may form part of the product slate. The exact product slate depends on the reactor configuration, operating conditions and the catalyst that is employed. For example this has been described in the article Catal. Rev.-Sci. Eng., 23 (1&2), 265-278 (1981) or Hydroc. Proc. 8, 121-124 (1982), which is included by reference.
[0047] Preferred reactors for the production of heavier hydrocarbons are slurry bed or tubular fixed bed reactors, while operating conditions are preferably in the range of 160-280° C., in some cases in the 210-260° C. range, and 18-50 bar, in some cases preferably between 20-30 bar.
[0048] The catalyst may comprise active metals such as iron, cobalt, nickel or ruthenium. While each catalyst will give its own unique product slate, in all cases the product slate contains some waxy, highly paraffinic material which needs to be further upgraded into usable products. The LTFT products can be hydroconverted into a range of final products, such as middle distillates, naphtha, solvents, lube oil bases, etc. Such hydroconversion usually consists of a range of processes such as hydrocracking, hydroisomerisation, hydrotreatment and distillation.
[0049] For this invention, a suitable kerosene fraction is isolated from the hydroprocessed FT product using known methods. This LTFT-based kerosene is characteristically paraffinic and will usually contain little or no aromatics.
[0050] An example of suitable hydroprocessing conditions for this process step include:
temperatures of between 330 and 380° C. pressures of between 35 and 80 bar Liquid Hourly Space Velocity (LHSV) values of 0.5 to 1.5 per hour
A suitable reactor for this process would be a trickle flow fixed bed reactor.
[0054] This LTFT-derived kerosene fraction is then blended with a tar-derived kerosene fraction so as to achieve suitable physicochemical properties for a final aviation fuel or aviation fuel component. These may include the properties indicated in Table 1.
Tar-Derived Kerosene Component
[0055] Where syngas is required from coal for an FT process, by means such as high temperature gasification, for example high temperature entrained flow gasification processes, the higher temperatures required to produce syngas usually result in little or no useful tar product as this is cracked or hydrogenated during the gasification process.
[0056] The specific tar-derived kerosene fraction used in this invention is generated during a medium temperature gasification process, for example a Fixed Bed Dry Bottom (FBDB) (trade name) coal gasification process. During this process, typical temperature ranges for the included sub-processes may be:
combustion; from 1300-1500° C. gasification itself; from 700-900° C. reactor outlet temperature; 450-650° C.
[0060] By employing a medium temperature gasification process, an aromatic- and naphthenic-containing tar component can be isolated during coal gasification. In high temperature gasification processes, this tar component will not be preserved.
[0061] A medium temperature coal gasification process is a gasification process wherein slagging of the coal ash can not be tolerated and a dry ash is produced. This process can be carried out in a fixed bed or fluidised bed gasifier.
[0062] A fixed bed dry bottom gasifier (or fluidised bed gasifier) is a non-catalytic, medium temperature, pressurised gasifier for the production of synthesis gas from a solid carbonaceous feedstock such as coal by partial oxidation of the feedstock in the presence of a gasification agent comprising at least oxygen and steam or air and steam, with the feedstock being in lump or granular form and being contacted with the gasification agent in a fixed bed (or fluidised bed) and with the fixed bed (or fluidised bed) being operated at a temperature below the melting point of minerals contained in the coal.
[0063] The tar component initially forms part of the raw synthesis gas. When the raw synthesis gas is quenched, most of the tar/oil components are condensed into the liquid phase along with the steam. As the raw synthesis gas is further cooled, further tar/oil components are condensed from the raw synthesis gas stream at each cooling stage. The resultant liquor (gas condensate) streams are cooled and the tar/oil fraction is then removed from the aqueous phase using a system of gravity separators.
[0064] Middle distillates can then be produced by hydrocracking this tar/oil component. Suitable hydrocracking conditions for this process include:
temperatures of between 330 and 380° C. pressures of between 125 and 180 bar Liquid Hourly. Space Velocity (LHSV) values of 0.25 to 1.0 per hour
A suitable reactor for this process would be a trickle flow fixed bed reactor.
[0068] These fractions have a hydrocarbon profile that is quite different to that observed from the mainstream LTFT product—displaying a significantly naphthenic character with some aromatics.
[0069] Typically the hydrocarbon types for this kerosene fraction comprise:
between 15 and 30 mass % aromatics between 60 and 80 mass % naphthenics between 5 and 15 mass % combined isoparaffins and normal paraffins.
[0073] The exact character of this tar fraction can be established using sophisticated analytical separation techniques such as two-dimensional gas chromatography (GC×GC).
Blend Characteristics
[0074] The tar-derived and LTFT-derived kerosene fractions are blended in order to obtain a suitable aviation fuel or fuel component.
[0075] This blend will characteristically have a high level of naphthenics, typically more than 30 volume %, but this is coupled with an isoparaffinic content that allows a mass ratio of naphthenics to isoparaffinic species which is less than 15.
[0076] The range of blends from 40 volume % tar-derived kerosene/60% LTFT-derived kerosene to 80% tar-derived kerosene/20% LTFT-derived kerosene was found to meet all DEFSTAN 91-91 requirements for Jet A-1 fuel.
[0077] A minimum content of 40 volume % of tar-derived kerosene was determined to be the amount required in order to meet an 8 volume % aromatics level. A maximum content of 80 volume % of tar-derived kerosene was required in order to meet the maximum density specification (0.840 kg/l at 15° C.).
[0078] A more preferred range for the blend is one where the ratio of the first (LTFT) and second (tar-derived) kerosene fractions is between 45:55 and 55:45
[0079] The final blend of the non-petroleum components has a distinct naphthenic-rich character imparted by the addition of the tar-derived kerosene produced using medium temperature, fixed bottom gasification. The final synthetic aviation fuel or fuel component will therefore typically have a characteristic naphthenic content of no less than 30 volume/0 and no more than 60 volume %.
[0080] A further advantage of this invention lies in the modification of the freezing point of the blends with respect to the blend components. Whilst the blend components themselves have freezing points which are lower than the maximum aviation kerosene freezing point specification, namely −47° C.; applicant surprisingly found that the blend mixtures had freezing point values significantly reduced from those of the components. It seems that some synergistic interaction between the blend components facilitates a freezing point reduction of the blends of up to about 20% from that of the original components themselves.
[0081] The applicants postulate that this advantage may stem from the use of chemical diluent effects in mitigating against the negative effects of certain hydrocarbon species in the blend components. It is known that both n-paraffins in LTFT kerosene and aromatics in tar-derived kerosene typically have a detrimental effect on freezing point because of their individual ease of crystallisation. It appears that blending these species with components that also have a significant proportion of iso-paraffins and naphthenics results in a surprising (i.e. non-linear or non-interpolated) decrease in freezing point. However, given that each component already contained advantageous species prior to blending, it is suggested that it is the interaction between the dominant species contained in each blend component that is core to observing this the effect. The ratio of the advantageous species, namely iso-paraffins to naphthenics, is therefore highlighted as a critical feature of this invention. In order to further define the effective chemical window for this surprising behaviour, the ratio of naphthenics to aromatic species may also be identified.
[0082] The invention will now be described with reference to the following non-limiting examples.
EXAMPLE
[0083] Various blends of tar-derived kerosene and LTFT-derived kerosene were prepared as previously described using methods known in the art. These were analysed alongside the blend components and the results compared to known data for coal-liquefaction derived aviation kerosene. The specification analysis was performed according to ASTM test methods and compared with JP-A jet fuel specifications. The hydrocarbon characteristics of each of the kerosene samples were determined using two-dimensional gas chromatography (GC×GC).
DESCRIPTION OF TABLES AND FIGURES
[0084] Table 1 summarises results of the blends and blend components; and
[0085] Table 2 gives detailed results for these samples.
[0086] FIG. 1 shows the hydrocarbon species distribution for a representative set of blends; and
[0087] FIG. 2 shows the freezing point values for this set of blends (with the inclusion of data for an out-of-specification blend for completion.)
[0000]
TABLE 1
Kerosene type
JP-A
LTFT/tar
LTFT/tar
Tar-
Coal-
Property
Units
spec.
LTFT
blend A
blend B
derived
derived*
LTFT kerosene
vol %
NA
100
50
25
—
NA
Tar-derived
vol %
NA
—
50
75
100
NA
kerosene
Hydrocarbon type (analysis by GCxGC)
n-paraffins
mass %
—
61.61
29.9
19.45
4.09
<1
iso-paraffins
mass %
—
37.38
19.3
13.01
3.13
Naphthenics
mass %
—
1
39.7
52.72
72.19
97.3
aromatics
mass %
—
0.1
11.1
14.81
20.59
2.1
Mass ratio of
—
—
0.1
2.1
4.1
23.1
>90
naphthenic: iso-
paraffins
Mass ratio of
—
—
10
3.58
3.56
3.51
46.3
naphthenics:
aromatics
Property measurements (evaluated according to ASTM test methods
Density@15° C.
g · cm −3
0.775-0.840
0.7364
0.8020
0.8342
0.8654
0.870
Viscosity @−20° C.
cSt
8.0 max
1.84
3.68
4.51
7.46
7.5
Smoke point
mm
25.0 mm
29
28
29
29
22
Freezing point
° C.
−47
−49.8
−58.4
−55.8
−50.9
−53.9
Lubricity:
mm
0.85 max
0.60
0.51
0.66
0.54
—
BOCLE, WSD
*figures extracted from “Development of an advanced, thermally stable, coal-based jet fuel”; Schobert, H et al; Fuels Processing Technology, 89, (2008), 364-378
[0000]
TABLE 2
Detailed properties of a tar-derived/LTFT kerosene blends
Results
LTFT-tar-
LTFT-tar-
LTFT-tar-
Tar-
LTFT
derived
derived
derived
derived
Property
Units
Limits
kerosene
(75/25)
(50/50)
(25/75)
kerosene
Colour, Saybolt
—
Report
+30
>+30
>+30
+30
>+30
Particulate
mg/L
1.0
max
0.3
<0.1
<0.1
<0.1
<0.1
Contaminants
COMPOSITION
Total Acidity
mgKOH/g
0.015
max
0.058
<0.001
<0.001
<0.001
<0.001
Olefins
vol %
0
0
0
0
0
Paraffins 1
vol %
100.0
95.3
91.4
85.9
83.9
Total Aromatics
vol %
26.5
max
0
4.7
8.6
14.1
16.1
Total Sulphur
mg/kg
<1
10
12
11
<1
Total Nitrogen
mg/kg
<1
<1
1
<1
Naphthalene
vol %
3.0
max
0.18
<0.01
1.16
0.17
Bromine No
gBr/100 g
<0.1
<0.1
<0.1
<0.1
VOLATILITY
Initial Boiling Point
° C.
Report
136.4
142.5
145.7
152.8
168.3
5%
° C.
151.4
156.1
160.5
165.7
184.7
10%
° C.
205.0
max
154.0
158.2
162.8
173.8
191.0
20%
° C.
159.7
164.9
171.4
183.7
198.8
30%
° C.
165.0
170.8
180.1
192.1
207.9
40%
° C.
171.0
177.9
188.3
201.3
215.9
50%
° C.
Report
182.7
184.9
197.3
210.3
223.9
60%
° C.
188.7
192.3
206.0
219.5
231.1
70%
° C.
195.1
200.5
215.3
228.9
238.5
80%
° C.
202.6
209.6
227.6
239.5
246.5
90%
° C.
Report
208.0
225.0
244.9
251.7
254.9
95%
° C.
211.0
240.1
255.5
258.8
260.4
Final Boiling Point
° C.
300.0
max
215.8
256.2
261.0
264.0
264.6
Recovery
vol %
98.6
98.4
98.3
98.3
98.4
T 50 -T 10
° C.
>20
28.7
26.7
34.5
36.5
32.9
T 90 -T 10
° C.
>40
54.0
66.8
82.1
77.9
63.9
Flash Point
° C.
38.0
min
40.5
44
46.5
53
52.0
Density @ 15° C.
kg/L
0.775-0.840
0.7364
0.7695
0.8020
0.8342
0.8654
Density @ 20° C.
kg/L
0.771-0.836
0.7334
0.7665
0.7990
0.8312
0.8624
FLUIDITY
Freezing Point
° C.
−47.0
max
−49.8
−53.9
−58.4
−55.8
−50.8
Viscosity @ −20° C.
mm 2 /s
8.0
max
1.84
2.62
3.68
4.51
7.46
Viscosity @ 40° C.
cSt
?
1.09
1.28
1.52
1.82
COMBUSTION
Specific Energy
MJ/kg
42.80
min
44.29
43.80
43.40
43.00
42.70
Smoke Point
mm
25.0
min
29
27
28
29
29
CORROSION
Copper Corrosion
—
1
max
1B
1A
1B
1A
1B
THERMAL STABILITY (JFTOT) at 260° C.
Filter Pressure
mmHg
25.0
max
0
0
0
0
0
Differential
Tube Deposit
<3
<1
<1
<1
<1
<1
Rating
CONTAMINANTS
Existent gum
mg/100 mL
7
max
0.9
1.1
1.5
1.4
1.8
Water content
mg/kg
17
25
45
24
30
MSEP RATINGS
Microsep -
85
min
92
88
89
88
96
without Static
Dissipator Additive
LUBRICITY
BOCLE, WSD
mm
0.85
max
0.60
0.50
0.51
0.66
0.54
1 This paraffin characterisation includes all saturated hydrocarbon species - namely linear paraffins (iso and normal), as well as cycloparaffins (also known as naphthenes)
[0088] The claims of the patent specification which follow form an integral part of the disclosure thereof.
|
A fully synthetic aviation fuel or aviation fuel component is provided, having a total naphthenic content of more than 30 mass %, a mass ratio of naphthenic to iso-paraffinic hydrocarbon species of more than 1 and less than 15, a density (at 15° C.) of greater than 0.775 g·cm −3 , but less than 0.850 g·cm −3 , an aromatic hydrocarbon content of greater than 8 mass %, but less than 20 mass %, a freezing point of less than −47° C., and a lubricity BOCLE WSD value of less than 0.85 mm. A process for preparing a fully synthetic coal-derived aviation fuel or aviation fuel component by blending a LTFT and a tar derived blend component is also provided, as is a method of producing a coal-derived, fully synthetic aviation fuel or aviation fuel component from coal gasifier tar and an LTFT derived fraction.
| 2
|
This is a Continuation-in-part of U.S. patent application Ser. No. 08/378,651 filed on Jan. 25, 1995, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a wheel assembly, and more specifically to a wheel assembly for a cart or similar article wherein the wheel is releasably locked to an axle.
2. Description of the Related Art
Wheel assemblies used on small or lightweight vehicles, such as golf carts, tricycles, baby carriages, child's wagon, etc., typically have a metal or plastic wheel with a central aperture through which passes an axle. The wheel is retained on the axle by a metal cap having outwardly slanted metal teeth on the inner surface thereof. This cap is sometimes known as a "Tinnerman" fastener. The axle is slidably mounted within the aperture in the wheel and the cap is then mounted to the end of the axle to prevent the removal of the wheel. Typically, the cap is struck by a hammer to drive the cap onto the end of the axle. The teeth slide over the axle as the cap is mounted on the axle. Because of the reverse angle of the teeth, they dig into the axle to prevent the inadvertent removal of the cap from the axle.
The cap does not always function as intended. Occasionally, the cap is slanted on the axle when struck by a hammer and does not seat properly, resulting in premature loss of the cap. Further, the cap can be removed by simple tools, leading to the unwanted removal of the wheels by vandals. Also, once removed, the cap is sufficiently deformed or destroyed so that it generally cannot be reused.
Another wheel fastener system has been developed for use with these types of wheels. It has received a DIN standard approval and, accordingly, is sometimes called a DIN cart wheel. A circumferential groove is provided on or near the ends of the axle. The wheel has one or more pins which are spring loaded with a plain metal spring in the hub of the wheel. The pin or pins project into the circumferential groove in the axle. Unfortunately, the spring rusts or corrodes and ultimately breaks. The wheel then falls off the axle. The DIN cart wheel is also fairly expensive, especially as compared to the so-called "Tinnerman" fastener.
There are other prior devices for attaching a wheel to an axle. U.S. Pat. No. 5,188,430 to Chiu, issued Feb. 23, 1993 discloses a golf cart wheel assembly wherein a tubular shaft bushing is disposed within the hub of a wheel and has an opposing pair of integrally molded fingers whose tips are biased into openings in the side of the tubular shaft bushing where they are received in detents in the axle to retain the wheel to the axle. U.S. Pat. No. 5,277,480 to Chiu, issued Jan. 11, 1994, discloses a tubular sleeve snap-fit within the wheel hub and having press tabs diametrically positioned at the end of the tubular sleeve in such a manner that the tips of the press tabs are received within an annular groove on the end of the axle when the axle is inserted through the tubular sleeve to retain the axle to the wheel. The press tabs are released from engagement with the annular groove by pressing on the press tabs in the direction along the longitudinal axis of the tubular sleeve.
U.S. Pat. No. 849,952 to Willis, issued Apr. 9, 1907, discloses an axle nut comprising a bail with two inwardly directed and diametrically positioned fingers, which are received within diametrically positioned apertures in the axle. The fingers are removed by rotating the bail until the bail contacts a cam portion on the axle nut, which springs the bail to withdraw the fingers from the apertures.
U.S. Pat. No. 2,253,708 to Holman, issued Aug. 26, 1941, discloses a spring clip for retaining a wire spoked wheel to an axle having an annular groove at its end. The spring clip is secured at its ends to the hub, wraps around one of the spokes, and passes between the hub and the groove in the axle to secure the hub to the axle.
U.S. Pat. No. 531,701 to Smith, issued Jan. 1, 1895, discloses opposed spring plates having fingers that are biased through apertures in a hub so that the fingers abut a flange on the end of the axle to prevent the removal of the hub from the axle.
SUMMARY OF INVENTION
According to the invention a wheel assembly comprises an axle in which a circumferential groove or an indentation is located near the end of the axle. A wheel having a central hub with an opening in which the axle is received is retained on the axle by a wheel retainer. The wheel retainer comprises at least one generally semi-circular spring having a pair of lugs. Each lug is positioned at an end of the at least one semi-circular spring and abuts the hub of the wheel and has a keeper, which is shaped to fit into the circumferential groove or indentation of the axle. The generally semi-circular spring biases the keeper into the circumferential groove or indentation of the axle to retain the wheel on the axle.
The wheel retainer preferably has two generally semi-circular springs forming a circular shape with the lugs. The lugs can have a spacer extending outwardly, adapted to contact a cap and to maintain the cap in a predetermined spaced relationship to the wheel. The cap can be mounted to a central portion of the wheel for covering the wheel retainer and to retain the wheel retainer in contact with the wheel. Preferably, the wheel retainer is integrally molded from a thermoplastic material. A web can be positioned adjacent each of the lugs to define a tool guide aperture for retracting the keepers from the groove to remove the wheel from the axle. A tool is preferably used to retract the keepers from the groove. The tool is generally U-shaped and comprises a pair of spaced shafts connected by a handle. The ends of the spaced shafts have ramped outer surfaces that abut the web to retract the keepers from the groove upon insertion of the tool into the tool guide apertures. Alternatively, the lugs can also be retracted by squeezing the two springs toward each other.
The wheel assembly according to the invention can be easily assembled and disassembled without destroying the fastening member, yet the wheel retainer is sufficiently obscure and hidden from view so that the uneducated or potential vandal will find it difficult to remove the wheel from the axle. The retainer is made from a non-corrodible plastic material so that it will be long-lived. Further, the seating of the retainer on the axle is easily seen and felt by the assembler. The assembly can take place essentially without any tools.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be described with reference to the drawings wherein:
FIG. 1 is an assembly view of the wheel assembly according to the invention;
FIG. 2 is a sectional view of the assembled wheel assembly of FIG. 1 taken along line 2--2 of FIG. 1 with the wheel locked to the axle;
FIG. 3 is a view substantially identical to FIG. 2, except that a tool unlocking the wheel assembly is shown;
FIG. 4 is a plan view of a spring in the wheel assembly according to the invention;
FIG. 5 is a bottom view of the spring of FIG. 4;
FIG. 6 is a sectional view of the spring shown in FIGS. 4 and 5 taken along line 6--6 of FIG. 4; and
FIG. 7 is an assembly view of the wheel assembly according to an alternate embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, FIG. 1 illustrates the wheel assembly 10 according to the invention, which comprises an axle 12 on which is slidably mounted a wheel 14 with a tire 16. The wheel 14 is locked to the axle 12 by a wheel retainer 18, hidden from view when assembled by a cover 20, which is secured to the wheel by snap fingers 22. The wheel assembly 10 according to the invention can be used to mount a wheel to both ends of the axle 12. Only one of the wheel assemblies will be described in detail.
The axle 12 is formed from a rod 24 having a circumferential channel, indentation or groove 26 formed in the rod near the end thereof. A head 28 is defined by the portion of the rod 24 between the groove 26 and the end of the rod 24 and is preferably in the shape of a truncated cone. The rod 24 can be made from solid steel or can be hollow and made from other suitable structural materials.
The wheel 14 comprises a disc 32, having a hub 34 at the center of the disc and a rim 36 at the periphery of the disc. A plurality of support ribs 38 extend from the hub to the rim 36 to give structural support to the wheel 14. The tire 16 is mounted to the rim 36 of the wheel 14. The disc 32, hub 34, rim 36 and support ribs 38 of the wheel 14 are preferably molded as a single unit from a suitable thermoplastic material. The disc 32 also has four snap apertures 40 to receive snap fingers 22 in mounting the cover 20 to the wheel 14 and disc apertures 48 to provide access for a tool 90 to unlock the wheel retainer 18. The disc apertures 48 are positioned on the disc 32 so that they lie along a line passing through the notches 44, 46 in the hub.
The hub 34 defines a central aperture 42 of the wheel 14 through which the axle 12 passes upon assembly of the wheel assembly 10. Notches 44 and 46 are located in the wall of the hub 34 and are diametrically opposed to one another.
Referring to FIGS. 1 and 4-6, the axle 12 is secured to the wheel 14 by the wheel retainer 18, which comprises diametrically opposed lugs 50, 52 connected by two semi-circular spring members 54, 56, respectively. The lugs 50, 52 are mirror images of each other. Ring-shaped webs or tool guides 58, 60 extend from the lugs 50, 52 and define tool apertures 62, 64, respectively. When the wheel assembly 10 is assembled, the centers of the tool apertures 62, 64 are radially inwardly offset from the centers of the disk apertures 48 so that the lugs 50, 52 are moved outwardly upon the insertion of the tool 90. Positioning tabs 66, 68 extend away from the tool guides 58, 60 and position the wheel retainer 18 with respect to the disc 32 of the wheel 14. Spacers 70, 72 extend away from the tool guides 58 and 60 in a direction opposite the positioning tabs 66, 68. The spacers abut the cover 20 when assembled and locate the wheel retainer 18 between the cover 20 and the wheel 14.
The lugs 50, 52 also have a pair of keepers 74, 76, which extend away from the tool guides 58, 60 and toward the center of the aperture defined by the semi-circular springs 54, 56 and lugs 50, 52. The keepers 74, 76 are sized to fit within the groove 26 of the axle to lock the axle 12 to the wheel 14. Each of the keepers 74, 76 has a beveled surface 78, 80 to aid the insertion of the head 28 of the axle 12 through the lugs 50, 52 upon assembly of the wheel assembly 10. Shoulders 82 on the keepers 74, 76 are sized to bottom on the notches 44 and 46.
The cover 20 is somewhat hemispherical in shape with multiple notches 84 disposed about the cover 20 and which coincide with the spacing of the support ribs 38 of the wheel 14 so that when the cover 20 is mounted on the wheel 14, the support ribs 38 are received within the notches 84. Snap fingers 22 extend axially from the perimeter of the cover and pass through the aperture 40 to affix the cover 20 to the disc 32 upon assembly of the wheel assembly 10.
Referring to FIGS. 1-3, to assemble the wheel assembly 10, the wheel retainer 18 is oriented with respect to the wheel 14 so that keepers 74, 76 are in alignment with notches 44, 46 of the hub 34. The wheel retainer 18 is moved into contact with the wheel 14. As the wheel retainer 18 is pressed against the wheel 14, the keepers 74, 76 are received within the notches 44, 46, respectively. The wheel retainer 18 is pressed toward the disc 32 until the shoulders 82 seat in the bottom of the notches 44 and 46. With the wheel retainer 18 in this position, the semi-circular springs 54, 56 are positioned outward of the support ribs 38 of the wheel 14 and in contact therewith. In this position, the keepers 74, 76 extend into the aperture 42 of the hub 34. The cover 20 is positioned over the wheel retainer 18 so that the snap fingers 22 align with the snap aperture 40 and the support ribs 38 are received within the notches 84 of the cover 20. Snap fingers 22 are inserted through the snap aperture 40 to secure the cover 20 to the wheel 14. When the cover 20 is assembled to the wheel 14, the cover 20 abuts the spacers of the retainers 70, 72 as seen in FIG. 2 to limit the movement of the wheel retainer 18 with respect to the wheel 14 and cover 20.
Referring to FIGS. 1 and 2, the wheel 14 is mounted to the axle 12 by first assembling the wheel 14, wheel retainer 18 and cover 20 as previously described. The axle 12 is inserted into the aperture 42 of the hub 34 on the opposite side of the wheel 14 on which the wheel retainer 18 is disposed. As the axle 12 is inserted, the head 28 abuts the beveled surfaces 78, 80 of the keepers 74, 76 and moves the lugs 50, 52 outwardly with respect to the hub 34, flexing outwardly the semi-circular springs 54. Upon further insertion of the axle 12, the groove 26 will align with the keepers, 74, 76 and the flexed semi-circular springs 54, 56 will urge the keepers 74, 76 into the groove 26, locking the wheel 14 to the axle 12.
Referring to FIG. 3, tool 90 is used to unlock the wheel 14 from the axle 12. Tool 90 has a hand grip 92 from which extends opposed cylindrical shafts 94, 96, each having beveled or ramped surfaces 98, 100. Alternatively, the surfaces 98, 100 can be rounded. The shafts 94, 96 are inserted into the diametrically opposed disc apertures 48 in the disc. As the shafts 94, 96 are inserted through the disc 32 and into the tool apertures of the wheel retainer 18, the ramped surfaces 98, 100 abut the tool guides 58, 60 and move the lugs 50, 52 outwardly as the tool guides 58, 60 travel along the ramped surfaces 98, 100. The shafts 94, 96 are moved axially until the lugs 50, 52 extend radially outwardly a sufficient distance so that the keepers 74, 76 are withdrawn from the groove 26. The axle 12 can be easily removed from the wheel hub 34 by pulling on the axle 12 from the wheel 14.
Turning now to FIG. 7, an alternate arrangement of a wheel assembly 105 is shown, wherein like numerals in the previous embodiment are used to identify like parts in the present embodiment. In this embodiment, an end cap 110 is received within the aperture 42 of the hub 34. The end cap extends slightly outwardly from the end of the hub 34, for example, about 0.020-0.030 inch and extends slightly into the aperture 42 of the hub 34, for example, about 0.020-0.030 inch. The thickness of the end cap 110 is such that the keepers 74, 76 can fit into a pair of oppositely disposed openings 112 (only one of which is shown in FIG. 7) on the end portion of the hub 34. Each opening 112 extends between a respective notch 44, 46 and the end cap 110. The end cap 110 is preferably integrally molded with the hub 34 when the wheel 14 is manufactured, but can also be formed separately and bonded to the hub through ultrasonic welding, adhesives, press-fitting, or other well-known securing means.
To assemble the wheel assembly 105, the wheel retainer 18 is oriented with respect to the wheel 14 so that keepers 74, 76 are in alignment with notches 44, 46 of the hub 34. The wheel retainer 18 is moved into contact with the wheel 14. As the wheel retainer 18 is pressed against the wheel 14, the keepers 74, 76 are spread apart over the end cap 110 through deflection of the generally semi-circular springs 54, 56 and are received within the notches 44, 46, respectively. The wheel retainer 18 is pressed toward the disc 32 until the keepers 74, 76 clear the end cap 110 and the shoulders 82 seat in the bottom of the notches 44 and 46. When the keepers 74, 76 slide past the end cap 110, the springs 54, 56 spring back to their original undeflected state such that the keepers 74, 76 extend through the openings 112 into the aperture 42 of the hub 34 and lock the wheel retainer in position on the wheel 14. With the wheel retainer 18 in this locked position, the semi-circular springs 54, 56 are positioned outward of the support ribs 38 of the wheel 14 and in contact therewith. The axle 12 and the cover 20 can then be installed as previously described. When installed, an inner surface of the cover 20 preferably abuts an outer surface of the end cap 110. In this preferred arrangement, the spacers 70, 72 can be eliminated since they serve the same function. In the previous embodiment, the cover 20 and spacers 70, 72 function to prevent the retainer 18 from sliding off the wheel 14 and thus limit the relative sliding movement between the wheel 14 and the axle 12. In the present embodiment, the end cap 110 serves this function and also serves to prevent the wheel 14 from sliding too far onto the axle 12 during assembly and thus, pushing the cover 20 from the hub 34. The end cap 110 also resists a greater amount of axial and lateral forces exerted between the axle and wheel than the cover 20 alone, and serves to strengthen the hub 34 against lateral forces by enclosing the aperture 42.
The wheel assembly thus provides a reusable, releasably lockable mounting for a wheel on an axle. The wheel is quickly and easily mounted on the axle without the need of tools. The wheel retainer is secure and reliable. It will not fall off in use. Seating of the spring keepers into the axle groove is easily seen and felt during assembly of the spring into the axle. The wheel retainer is hidden by the cover and is not easily unlocked without the special tool, reducing vandalism and tampering. Also, the wheel retainer is not visible when the wheel assembly is assembled, providing a potential vandal little information on how to remove the wheel. Yet a knowledgeable worker can quickly remove the wheel from the axle. The plastic spring is long lived and will not corrode as metal springs do.
While particular embodiments of the invention have been shown, it will be understood, of course, that the invention is not limited thereto since modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. For example, although the wheel retainer has two opposing semi-circular springs, it is within the scope of the invention for the use of only a single semi-circular spring for biasing the lugs. The shape of the spring can be generally rectangular or circular. Thus, as used herein, the term "generally semi-circular" is intended to include half oval as well as half rectangular shapes. Also, one or more indentations can replace the circumferential groove. The keepers will then be received within the indentation. Reasonable variation and modification are possible within the scope of the foregoing disclosure of the invention without departing from the spirit of the invention.
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A reusable, releasably lockable wheel assembly comprising a wheel having a centrally disposed hub defining an aperture in which is received an axle. A spring having diametrically opposed lugs is disposed on one side of the hub and the lugs extend into the aperture of the hub so that when the axle is inserted into the aperture, the lugs are biased into the groove on the end of the axle to lock the wheel to the axle. The lugs can be forced outwardly by a tool to withdraw the lugs from the groove so that the axle can be unlocked with respect to the wheel for removal of the wheel. In one embodiment, cooperation between a wheel cover and the spring limits slidable movement between the wheel and axle. In another embodiment, cooperation between an end cap on the wheel hub and the spring limits the slidable movement.
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CROSS REFERENCE TO RELATED APPLICATION
This application claims benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Ser. No. 61/192,273 filed on Sep. 17, 2008 in the United States Patent and Trademark Office entitled “Hanging Float Rack.” The entire disclosure of U.S. Provisional Patent Application Ser. No. 61/192,273 is incorporated by reference as if fully disclosed herein.
TECHNICAL FIELD
The disclosure relates generally to storage systems, and in particular to storage of floatation devices.
BACKGROUND
A standard closed foam float design includes a pillow formed by a loop in the foam material. Such floats are often difficult to store and cause clutter near pools, in garages, or on boats.
SUMMARY
Embodiments of the present disclosure generally provide a rack for storing floats. A float rack may comprise a vertical support post, a plurality of slip-Ts and a plurality of float support arms. The vertical support post will typically have a top end and a bottom end. The slip-Ts are connected to the vertical support post to provide a rotating joint about the vertical support post. The float support arms are attached to the slip-Ts.
Other technical features may be readily apparent to one skilled in the art from the following figures, descriptions and claims.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of this disclosure and its features, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a view of a float rack installed to a building near a swimming pool;
FIG. 2 is a close-up view of the float rack of FIG. 1 with a float;
FIG. 3 is a close-up view of a float rack with a float;
FIG. 4 is a close-up of a float rack with two floats;
FIG. 5 is a top view of the float rack of FIG. 4 ;
FIG. 6 is a view of a float rack;
FIG. 7 is a top view of the float rack in FIG. 6 ;
FIG. 8 is a view of a float rack;
FIG. 9 is a top view of the float rack in FIG. 8 ; and
FIG. 10 is a sectional view of the float rack in FIG. 8 .
DETAILED DESCRIPTION
The present disclosure generally provides
FIG. 1 is a view of a float rack 10 with floats 12 installed on a building 14 near a swimming pool 16 . Float rack 10 has three arms 18 sized to support floats 12 as shown. Float rack 10 is mounted to an outside wall of building 14 in the figure shown, but may be mounted inside, as in a garage or storage area. Floats 12 are common closed cell foam floats with a loop forming a headrest 20 . Arms 18 are sized to fit within headrest 20 of float 12 .
FIG. 2 is a close-up view of the float rack 10 of FIG. 1 with a float 12 hanging by headrest 20 off of arm 18 . Arm 18 is shown to have ribbing 22 in its outer surface. Ribbing 22 provides an improved aesthetic and allows for easy sliding of headrest 20 over arm 18 . Arm 18 also has an end cap 24 to seal the arm 18 and provide for a smooth end. Arms 18 are attached to slip-Ts 26 which rotate about a vertical support post 28 . Vertical support post 28 has an upper end 30 and a lower end 32 , each having an end cap 24 .
Near the upper end 30 of vertical support post 28 is a fixed-T 34 attached to upper support 36 . A surface mount 38 is connected to the upper support 36 opposite the fixed-T 34 . Near the lower end 32 of vertical support post 28 is another fixed-T 34 attached to a lower support 40 . Another surface mount 38 is connected to the lower support 40 opposite the fixed-T 34 . Lower support 40 is slightly longer than upper support 36 to allow arms 18 to be aligned on one side of vertical support post 28 with multiple floats 12 .
Screws 42 are placed adjacent to slip-Ts 26 to prevent unwanted axial movement along vertical support post 28 while allowing rotation of slip-Ts 26 about vertical support post 28 .
FIG. 3 is a close-up view of a float rack with a float 12 and twice as many arms 12 as in FIGS. 1 and 2 . Vertical support post 28 is elongated to allow for two slip-Ts 26 between the fixed-T 34 and the upper end 30 of vertical support post 28 . A single screw 42 is still sufficient to restrain unwanted axial movement as slip-Ts 26 rotate against each other without interference. Likewise two slip-Ts 26 are positioned between the fixed-T 34 and the lower end 32 of vertical support post 28 . Similarly two slip-Ts 26 are positioned near the middle of vertical support post 28 between fixed-Ts 34 .
Again, lower support 40 is slightly longer than upper support 36 to allow three arms 18 to be aligned on each side of vertical support post 28 with multiple floats 12 .
FIG. 4 is a close-up of a float rack 10 with two floats 12 hanging by headrests 20 . In this embodiment the slip-Ts 26 are arranged along vertical support post 28 between fixed-Ts 34 . The uppermost arm 18 is similar to those discussed with regards to FIGS. 1 , 2 , and 3 . The three lower arms 18 each have an elbow 44 on arm 18 and a spacing member 46 , 48 , 50 between the elbows 44 and the slip-Ts 26 . The spacing element 46 is shorter than spacing element 48 which is in turn shorter than spacing element 50 . Thus spacing elements 46 , 48 , 50 act to stagger arms 18 and provide space for floats 12 . Thus upper support 36 and lower support 40 may be the same length.
FIG. 5 is a top view of the float rack 10 of FIG. 4 more clearly showing the different lengths of spacing elements 46 , 48 , 50 and the resultant spacing of arms 18 .
FIG. 6 is a view of a float rack 60 having a vertical support post 28 and three fixed-Ts 34 supporting pairs of arms 18 with end caps 24 . The fixed-Ts 34 are arranged to provide an even distribution of arms 18 as shown in FIG. 7 . Vertical support post 28 is secured in base 52 .
FIG. 7 is a top view of the float rack 60 in FIG. 6 showing the arrangement of arms 18 .
FIG. 8 is a view of a float rack 70 having a vertical support post 78 and a base 52 . Slip-Ts 26 support arms 18 with end caps 24 . Support post 78 may be a composite support post made of an outer support post 54 and an inner support post 56 , as shown in FIG. 10 . In the alternative, vertical support post 78 may be a single element with a screw below the slip-Ts 26 from unwanted axially movement.
FIG. 9 is a top view of the float rack 70 in FIG. 8 showing that arms 18 may rotate independently about vertical support post 78 .
FIG. 10 is a sectional view of the float rack 70 in FIG. 8 showing a composite version of vertical support post 78 . The composite version of vertical support post 78 has an outer support post 54 extending from base 52 to the bottom of slip-Ts 26 . Inner support post 56 extends from base 52 to the top of slip-Ts 26 . Slip-Ts 26 are sized to fit about inner post 56 but not slide over outer post 54 such that the terminus of outer post 54 forms a shoulder to support slip-Ts 26 . Inner post 56 runs the entire length of outer post 54 to provide additional rigidity to vertical support post 78 .
All of the above embodiments, or parts thereof, may be made with a thermoplastic polymer to prevent corrosion and rusting. Polyvinyl chloride (PVC) is a suitable material for these embodiments and furniture grade PVC is useful where a thicker wall is desired. It is possible to obtain furniture grade PVC with a colorant treatment throughout the material to provide a more pleasant appearance and protection from fading, cracking, and brittleness. Where screws 40 are required they may be made of stainless steel to provide a non-corrosive alternative that has sufficient strength.
It may be advantageous to set forth definitions of certain words and phrases used in this patent document. The terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation. The term “or” is inclusive, meaning and/or. The phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like.
While this disclosure has described certain embodiments and generally associated methods, alterations and permutations of these embodiments and methods will be apparent to those skilled in the art. Accordingly, the above description of example embodiments does not define or constrain this disclosure. Other changes, substitutions, and alterations are also possible without departing from the spirit and scope of this disclosure, as defined by the following claims.
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Embodiments of the present disclosure generally provide a rack for storing floats. A float rack may comprise a vertical support post, a plurality of slip-Ts and a plurality of float support arms. The vertical support post will typically have a top end and a bottom end. The slip-Ts are connected to the vertical support post to provide a rotating joint about the vertical support post. The float support arms are attached to the slip-Ts.
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TECHNICAL FIELD
Embodiments of the subject matter disclosed herein generally relate to methods and devices and, more particularly, to mechanisms and techniques for cooling internal components of a downhole device using a heat exchanger based on a Stirling cycle.
BACKGROUND
Like other manufacturing disciplines, well drilling technology has been integrated with electronics for measurements, computing, communications, etc. As well drilling capabilities have allowed drilling of deeper wells, the temperature of the well fluid, otherwise known as “mud” has increased to the point where insulation and/or cooling of the downhole electronics is required to keep the electronics operational. Attempts have been made to insulate the electronics but even if a truly adiabatic insulator was available, the heat generated by the electronics themselves would lead to overheating if a cooling mechanism was not incorporated into the design of the electronics system.
Attempts have been made to provide a coolant to the electronic systems but the depth of state of the art wells has made this task difficult. Typical wells can be many thousands of feet deep and can include bends in the well that make plumbing one or more coolant lines to the drill head difficult. Further, existing methods of chaining multiple measurement and data collection downhole tools together in a single well further complicates an already difficult task of cooling individual tools and their associated electronic components. Further, attempts have been made to insulate the electronic components from the heat associated with the external environment but these attempts have resulted in a fixed operational time based on the amount of time required for the heat source to overcome the insulator, combined with heat generated by the electronics, and raise the temperature of the electronic components to a temperature at which they cannot operate.
Many prior art systems and mechanisms have evolved to transfer heat from a higher temperature region to a lower temperature region or to perform mechanical work based on the aforementioned energy transfer. One such device for performing mechanical work based on the described temperature difference is a Stirling engine. A Stirling engine is a device that converts thermal energy into mechanical energy by exploiting a difference in temperature between two regions.
The Stirling engine operates on the principle of the Stirling cycle which consists of four thermodynamic processes acting on a working fluid. The Stirling cycle consists of an isothermal expansion, an isovolumetric cooling, an isothermal compression and a isovolumetric heating. The output of the Stirling cycle is the ability to perform mechanical work based on movement of the piston in the Stirling engine. Noteworthy in the theory of the Stirling cycle is the reversible nature of the Stirling cycle. Accordingly it is possible to provide the mechanical energy to the Stirling engine and create a heat exchanger capable of transferring heat from a region of lower temperature to a region of higher temperature.
Accordingly, it would be desirable to provide devices and methods that avoid the afore-described problems and drawbacks of cooling downhole electronics.
SUMMARY
According to one exemplary embodiment, there is a heat pump apparatus comprising a plurality of flexible barriers separating a location to remove heat from a location to add heat and enclosing a volume through which said heat transfers. Next in the exemplary embodiment, a heat transfer fluid, contained in the volume, for transferring heat based on an input of mechanical energy. Continuing with the exemplary embodiment, a plurality of mechanical agitators for imparting the mechanical energy as compressive and expansive force on the volume an alternating the location of the heat transfer fluid from a position adjacent to the location to remove heat to a position adjacent to the location to add heat.
According to another exemplary embodiment, there is a down-hole drilling apparatus including an inner canister encasing drilling components, an outer canister encasing the inner canister and creating a void between the inner canister and the outer canister and a heat pump apparatus disposed in the void between the inner canister and the outer canister. The exemplary embodiment continues with the heat pump apparatus comprising a plurality of flexible barriers separating a location to remove heat from a location to add heat and enclosing a volume through which said heat transfers. Next in the exemplary embodiment, a heat transfer fluid, contained in the volume, for transferring heat based on an input of mechanical energy. Continuing with the exemplary embodiment, a plurality of mechanical agitators for imparting the mechanical energy as compressive and expansive force on the volume an alternating the location of the heat transfer fluid from a position adjacent to the location to remove heat to a position adjacent to the location to add heat.
According to another exemplary embodiment, there is a method for cooling down-hole drilling components. The method includes encasing the drilling components in a first canister. The exemplary embodiment continues with encasing the first canister in a second canister and providing a void area between the first canister and the second canister. Next, the exemplary embodiment continues with inserting a plurality of flexible barriers in the void area between the first canister and the second canister. Further, the exemplary embodiment continues with adding mechanical energy by alternately compressing and expanding a heat transfer fluid, contained in a plurality of pockets created by the plurality of barriers, with agitators, wherein said agitators are moving approximately ninety degrees out of synchronization with each other. Next in the exemplary embodiment, shifting the position of the plurality of pockets alternately from a cooler position during expansion to a hotter position during compression to transfer heat from the cooler position to the hotter position.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate one or more embodiments and, together with the description, explain these embodiments. In the drawings:
FIGS. 1 a - 1 b are prior art exemplary embodiments of a Beta Type Stirling Engine representing the four thermodynamic processes comprising the Stirling cycle;
FIG. 2 is an exemplary embodiment depicting the higher temperature and lower temperature regions of a radial cross-section typically associated with downhole electronics of a drilling apparatus;
FIG. 3 is an exemplary embodiment depicting the higher temperature and lower temperature regions of a radial cross-section typically associated with downhole electronics of a drilling apparatus including a plurality of beta type Stirling engines connected to the two regions across the void between the two regions with an exploded view of a Stirling engine;
FIG. 4 is an exemplary embodiment depicting the higher temperature and lower temperature regions of a radial cross-section typically associated with downhole electronics of a drilling apparatus including a moveable dual-barrier Stirling cycle heat exchanger located in the void between the two regions with an exploded view of the dual-barrier interacting radially with a plurality of pistons;
FIG. 5 is an exemplary embodiment depicting the higher temperature and lower temperature regions of a radial cross-section typically associated with downhole electronics of a drilling apparatus including a barrier ring Stirling cycle heat exchanger located in the void between the two regions with an exploded view of the barrier ring interacting tangentially with a working fluid;
FIG. 6 is an exemplary embodiment depicting the higher temperature and lower temperature regions of a radial cross-section typically associated with downhole electronics of a drilling apparatus including a barrier ring Stirling cycle heat exchanger located in the void between the two regions with an exploded view of the barrier ring interacting axially with a working fluid;
FIG. 7 is an exemplary embodiment depicting the higher temperature and lower temperature regions of a radial cross-section segment typically associated with downhole electronics of a drilling apparatus including a barrier ring Stirling cycle heat exchanger located in the void between the two regions with a support stud maintaining the annular gap between the inner and outer canister;
FIG. 8 is an exemplary embodiment depicting the higher temperature and lower temperature regions of a non-circular cross-section capable of supporting a barrier Stirling cycle heat exchanger located in the void between the two regions; and
FIG. 9 is a flow chart illustrating steps for operating a barrier type Stirling heat exchanger according to an exemplary embodiment.
DETAILED DESCRIPTION
The following description of the exemplary embodiments refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. The following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims. The following embodiments are discussed, for simplicity, with regard to the terminology and structure of turbo-machinery including but not limited to compressors and expanders.
Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
As shown in FIG. 2 , an exemplary embodiment depicts a cross-section of a typical canister arrangement for a downhole drilling apparatus. In the exemplary embodiment the inner canister 208 encloses the cooler region. In one aspect of the exemplary embodiment, it is desired to maintain the internal region 206 at a temperature low enough to permit uninterrupted operation of the electronics associated with the drilling operations, including but not limited to drill control, data collection and communications to external locations. In another aspect of the exemplary embodiment an outer canister 210 encases the inner canister 208 and provides a void area 204 between the inner canister 208 outer wall and the outer canister 210 inner wall. It should be noted in the exemplary embodiment that a support structure (not shown) maintains the predefined void area between the inner canister 208 and the outer canister 210 . Continuing with the exemplary embodiment, an external region 202 outside the outer canister 210 is at a temperature higher than the temperature of the internal region 206 inside the inner canister 208 and higher than the operational maximums of the electronics associated with the drilling operations. It should be noted in the exemplary embodiment that the external region 202 is a heat source with effectively unlimited capacity.
Looking now to FIG. 3 , an exemplary embodiment depicts another cross-section 300 of a typical canister arrangement for a downhole drilling apparatus. The cross-section 300 includes an inner canister 308 enclosing a cooler region 306 , with respect to a hotter region 302 , and an outer canister 310 encasing the inner canister 308 and provides a void area 304 between the outer wall of the inner canister 308 and the inner wall of the outer canister 310 . It should be noted that the hotter region 302 is effectively unlimited with regard to its heat capacity.
Continuing with the exemplary embodiment, a plurality of beta type Stirling engines are connected between the outer wall of the inner canister 308 and the inner wall of the outer canister 310 . In one aspect of the exemplary embodiment, the Stirling engines 312 serve as a support structure for maintaining the void area 304 between the inner canister 308 and the outer canister 310 . In another aspect of the exemplary embodiment, the Stirling engines 312 are constructed of an insulating material to prevent the transfer of heat from the hotter region 302 to the cooler region 306 . Further in the exemplary embodiment, mechanical energy is provided to the Stirling engines 312 to reverse the Stirling cycle forcing the Stirling engines 312 to operate as heat pumps for cooling the region inside the inner canister 308 .
As depicted in the exploded view of the Stirling Engines 312 , mechanical energy (not shown) is provided to a piston 314 to compress the working fluid in the compression zone 316 , therefore heating the working fluid and transferring heat energy through the outer canister 310 to the hotter region 302 based on the position of the displacer 318 moving the working fluid to the end of the Stirling engine 312 adjacent to the hotter region 302 outside the outer canister 310 . Next in the exemplary embodiment, as the piston 314 expands the volume, the working fluid cools and the displacer 318 forces the cooler working fluid to the end of the Stirling engine adjacent toward the cooler inner canister 308 therefore cooling the region inside the canister 306 .
Further, it should be noted in the exemplary embodiment that additional parallel planes of Stirling engines can be configured based on operational parameters and conditions dictating the amount of required cooling. It should be noted in the exemplary embodiment that the number of Stirling engines in a single cross-sectional plane is not limited to the number depicted in cross-section 300 and can be a larger or smaller number based on circumstances associated with the particular heat transfer and/or structural requirements.
Looking now to FIG. 4 , an exemplary embodiment depicts another cross-section 400 of a typical canister arrangement for a downhole drilling apparatus. The cross-section 400 includes an inner canister 408 enclosing a cooler region 406 , with respect to a hotter region 402 , and an outer canister 410 encasing the inner canister 408 and providing a void area 404 between the outer wall of the inner canister 408 and the inner wall of the outer canister 410 . It should be noted that the hotter region 402 is effectively unlimited with regard to its heat capacity.
Continuing with the exemplary embodiment, a flexible inner barrier 412 and a flexible outer barrier 414 , located in the void space 404 between the inner canister 408 and the outer canister 410 , separates an inner gas volume 416 from an outer gas volume 418 and encases a heat transfer fluid 420 between the inner barrier 412 and the outer barrier 414 . Next in the exemplary embodiment, a plurality of inner pistons 422 is attached to the outer surface of the inner canister 408 and exerts a radial force outward on the inner barrier 412 . Similarly in the exemplary embodiment, a plurality of outer pistons 424 is attached to the inner surface of the outer canister 410 and exerts a radial force inward on the outer barrier 414 .
Further in the exemplary embodiment, it should be noted that the inner canister pistons 422 and the outer canister pistons 424 are mounted such that they are diagonally across from each other as illustrated in the exploded view of FIG. 4 and oscillate approximately ninety degrees out of phase of each other. It should also be noted in the exemplary embodiment that the mechanical energy provided to the system to oscillate the inner barrier 412 and the outer barrier 414 can be provided, as illustrated in FIG. 4 , not only by pistons but also by electric motors, solenoids, piezoelectric ceramics, acoustic waves, etc.
The exemplary embodiment depicted in FIG. 4 illustrates the use of a series of radial force applications, by the exemplary pistons 422 / 424 , to oscillate the two barriers in such a manner as to input mechanical energy into the barriers and create a heat pump, based on a reverse Stirling cycle, for transferring heat from the cooler region 406 to the hotter region 402 and preserving a desired temperature of operation within the cooler region 406 inside the inner canister 408 . For example, an inner canister piston 422 acts as a compression piston in the hot cycle, compressing and heating the heat transfer fluid 420 while displacing the compressed and heated fluid toward the higher temperature outer canister 410 and allowing heat transfer from the heat transfer fluid to the hotter region 402 . Continuing with the example of the exemplary embodiment, approximately ninety degrees out of phase with the inner canister piston 422 , the outer canister piston 424 acts a compression piston in the cold cycle, moving an adjacent section of the heat transfer fluid 420 toward the lower temperature inner canister 408 while the inner canister piston 422 retracts to increase the volume occupied by the heat transfer fluid 420 and cools the heat transfer fluid 420 with the channel between the inner barrier 412 and the outer barrier 414 acting as a regenerator and allowing heat transfer from the cooler region 406 to the heat transfer fluid 420 .
Looking now to FIG. 5 , an exemplary embodiment depicts another cross-section 500 of a typical canister arrangement for a downhole drilling apparatus. The cross-section 500 includes an inner canister 508 enclosing a cooler region 506 , with respect to a hotter region 502 , and an outer canister 510 encasing the inner canister 508 and providing a void area 504 between the outer wall of the inner canister 508 and the inner wall of the outer canister 510 . It should be noted that the hotter region 502 is effectively unlimited with regard to its heat capacity.
Continuing with the exemplary embodiment, a plurality of saw tooth outer agitators 512 are paired with a plurality of saw tooth inner agitators 514 functioning as the hot cycle compression piston and the cold cycle compression piston as described in the example for FIG. 4 . In the exemplary embodiment, the saw tooth agitators 512 , 514 oscillate in an angular direction around the shared axis of the inner canister 508 and the outer canister 510 . Further in the exemplary embodiment, the barrier ring 516 acts as the regenerator described in the example for FIG. 4 . In a similar manner as described for the example of FIG. 4 , adding mechanical energy to the agitators 512 , 514 operates a reverse Stirling cycle heat pump and transfers heat from the cooler region 506 to the hotter region 502 based on compression and expansion of a heat transfer fluid located in an inner volume 518 and an outer volume 520 between inner canister 508 and outer canister 510 .
Looking now to FIG. 6 , an exemplary embodiment depicts another cross-section 600 of a typical canister arrangement for a downhole drilling apparatus. The cross-section 600 includes an inner canister 608 enclosing a cooler region 606 , with respect to a hotter region 602 , and an outer canister 610 encasing the inner canister 608 and providing a void area 604 between the outer wall of the inner canister 608 and the inner wall of the outer canister 610 . It should be noted that the hotter region 602 is effectively unlimited with regard to its heat capacity.
Continuing with the exemplary embodiment, a saw tooth outer barrier 612 is paired with a saw tooth inner barrier 614 functioning as the hot cycle compression piston and the cold cycle compression piston respectively, as described in the example for FIG. 4 . Further in the exemplary embodiment, the barrier ring 616 acts as the regenerator described in the example for FIG. 4 . In a similar manner as described for the example of FIG. 4 , adding mechanical energy to the saw tooth barriers 612 , 614 operates a reverse Stirling cycle heat pump and transfers heat from the cooler region 606 to the hotter region 602 based on compression and expansion of a heat transfer fluid located in an inner volume 618 and an outer volume 620 between inner canister 608 and outer canister 610 . It should be noted in the exemplary embodiment that the barriers 612 , 614 , 616 are oriented in an axial direction with regard to the common axis shared by the inner and outer canisters 608 , 610 and the oscillation of the barriers 612 , 614 is in the axial direction.
Looking now to FIG. 7 , an exemplary embodiment depicts the saw tooth agitators of FIG. 5 including a support mechanism for maintaining the angular void between the inner canister 708 and the outer canister 710 . Continuing with the exemplary embodiment, a support stud 712 is connected to the inner canister 708 and the outer canister 710 . In the exemplary embodiment, the stud is a component of the barrier 718 between the outer agitators 720 and the inner agitators 722 . Further in the exemplary embodiment, slots 714 , 716 are cut in the agitator mechanism to allow the stud 712 to be attached to the inner canister 708 and the outer canister 710 . Continuing with the exemplary embodiment, the studs 712 maintain mechanical integrity and dimensional consistency between the inner canister 708 and the outer canister 710 and protect the heat pump components from crushing associated dimensional change of the void area between the inner canister 708 and the outer canister 710 . It should be noted in the exemplary embodiment that other support mechanisms such as, but not limited to, ball bearings, rollers or axial end studs can be used as a support mechanism for maintaining the angular void between the inner canister 708 and the outer canister 710 .
Looking now to FIG. 8 , the exemplary embodiment illustrates that the hotter region 802 can be constrained by non-circular inner barrier 810 with a non-circular void between the inner barrier 810 and an outer barrier 808 . In another aspect of the exemplary embodiment, the cooler outer region 806 , as described for the hotter region in the previous examples, can have an infinite capacity to absorb heat. It should be noted that other shapes of barriers and voids between barriers are possible and should not be limited by these examples. In another aspect of the exemplary embodiment, movement of barriers acting as a reverse Stirling cycle power pistons can be in radial, angular or axial directions as previously described for the previous exemplary embodiments.
An exemplary method embodiment for cooling components of a down-hole well drilling apparatus is now discussed with reference to FIG. 9 . FIG. 9 shows exemplary method embodiment steps for using a cooling system based on a reverse Stirling cycle to cool down-hole drilling components by transferring heat from an area housing the down-hole drilling components and transferring the heat to the drilling mud surrounding the outer casing of the drilling system. The exemplary method embodiment includes a step 902 of encasing drilling components in an inner canister. In one aspect of the exemplary method embodiment, the inner canister is typically cylindrical in shape and is typically the cooler region of the heat transfer path i.e. heat is removed from the volume inside the inner canister. It should be noted in the exemplary embodiment that the drilling components can be, but are not limited to, electronic components for control, data acquisition and communications and can generate heat based on component power consumption.
Next at step 904 , the exemplary method embodiment continues by encasing the inner casing with an outer casing. The outer casing is typically has the same shape as the inner casing and creates a void between the inner casing and the outer casing. It should be noted that the inner casing and the outer casing share the same rotational axis i.e. the separation distance between the outer wall of the inner casing and the inner wall of the outer casing is maintained. It should further be noted that the region outside the outer casing is typically the hotter region of the heat transfer path i.e. the heat removed from the cooler region inside the inner canister is transferred to the hotter region outside the outer casing.
Continuing with step 906 , the exemplary method embodiment inserts a plurality of flexible barriers in the void between the inner canister and the outer canister. It should be noted that in one exemplary embodiment, the barriers can have a saw tooth shape and can be oriented in an angular or an axial direction. Further, it should be noted in the exemplary embodiment that one or more additional barriers can be sandwiched between the inner and outer barrier and the inner and outer barrier can oscillate while the sandwiched barrier(s) can remain fixed and/or rigid. In another aspect of the exemplary embodiment, studs for maintaining dimensional integrity between the inner canister and the outer canister can be integrated in the sandwiched barrier(s) and extended through slots in the inner and outer barrier for attachment to the inner canister and the outer canister.
Next at step 908 , the exemplary embodiment adds mechanical energy to the flexible barriers. In the exemplary embodiment, the mechanical energy is provided by agitators moving in a radial, angular or axial direction. It should be noted that the movement can be an oscillation of the agitators with the agitators configured as opposing pairs oscillating approximately ninety degrees out of phase of each other. In another aspect of the exemplary embodiment, the phase difference between the opposing pairs of agitators can vary by a phase selected based on design, maximizing efficiency or maximizing the economic value. It should further be noted that a heat transfer fluid is also inserted in the volume between the inner flexible barrier and the outer flexible barrier. Continuing with the exemplary embodiment, the agitator movement imparts compressions and expansions on the heat transfer fluid resulting in localized hot and cold volumes sufficient to provide a heat transfer path between the cooler region inside the inner canister and hotter region outside the outer canister.
Continuing with step 910 , the exemplary embodiment transfers heat from the cooler region inside the inner canister to the hotter area outside the outer canister. It should be noted in the exemplary embodiment that the localized volumes of hotter and colder heat transfer fluid created by the agitator oscillations are displaced to a hotter outer location and a colder inner location, respectively, by the agitator movement, allowing the transfer of heat in the desired direction.
The disclosed exemplary embodiments provide devices and a method for implementing Stirling cycle coolers and energy generators in a down-hole drilling operation. It should be understood that this description is not intended to limit the invention. On the contrary, the exemplary embodiments are intended to cover alternatives, modifications and equivalents, which are included in the spirit and scope of the invention as defined by the appended claims. Further, in the detailed description of the exemplary embodiments, numerous specific details are set forth in order to provide a comprehensive understanding of the claimed invention. However, one skilled in the art would understand that various embodiments may be practiced without such specific details.
Although the features and elements of the present exemplary embodiments are described in the embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the embodiments or in various combinations with or without other features and elements disclosed herein.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements to those recited in the literal languages of the claims.
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Apparatus and method for cooling internal components of a down-hole well drilling apparatus. Components of the well drilling apparatus are encased in an inner canister that is further encased in an outer canister creating a void between the inner canister and the outer canister. Further, a plurality of moveable barriers is disposed between the inner canister and the outer canister and contains a heat transfer fluid. A plurality of agitators add mechanical energy to the plurality of moveable barriers compressing and expanding, while repositioning, the heat transfer fluid and creating a heat pump based on a reverse Stirling cycle to remove heat from the cooler inner canister and transfer the heat to the hotter environment outside the outer canister.
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RELATED APPLICATION DATA
[0001] This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/068,579 filed on Mar. 6, 2008.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This present invention is directed to improved skins or surfaces for light reflector umbrellas and methods of using light reflecting umbrellas.
[0004] 2. Description of the Related Art
[0005] Photographers use different types of lighting devices to create diffused light for photographing their subjects. Light directly from a light source, such as a strobe, comes in a straight line and can produce harsh, hard shadows on a subject. Conventional devices create soft diffused light by directing light through a diffusing material or by bouncing light off a second surface. A conventional lighting umbrella is one type of light “bouncing” source. In the conventional umbrellas, light from a bulb is bounced off the inside of the metalized umbrella to create a soft indirect light that creates softer shadows on the subject. A need exists for an improved light umbrella that expands the lighting options that photographers can use to shape the light and produce diffuse lighting to photograph their subjects.
SUMMARY OF THE INVENTION
[0006] The use of novel skins for light reflecting umbrellas and for methods of using light reflecting umbrellas. The invention described herein can be utilized for skins used with common reflectors known to skilled persons. Embodiments of the invention include the skin having a series of panels in stripes of alternating colors, in a shift configuration, in a checkered shift configuration, in a half and half configuration, in a modified half and half configuration with a center portion having a separate color combination, in a tricolor configuration, in a shifted tricolor configuration and in a configuration with a center portion having a different color. Other embodiments of the invention include the use of sequins secured onto the skin. Other and further advantages will appear to skilled persons from the written disclosure and figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is an elevation view of embodiments of the invention illustrating one arrangement of panels on the skin.
[0008] FIG. 2 is an elevation view of embodiments of the invention in a shift configuration.
[0009] FIG. 3 is an elevation view of embodiments of the invention in a checkered shift configuration.
[0010] FIG. 4 is an elevation view of embodiments of the invention in a half and half configuration.
[0011] FIG. 5 is an elevation view of further embodiments of the invention in a half and half configuration.
[0012] FIG. 6 is an elevation view of embodiments of the invention in a tricolor configuration.
[0013] FIG. 7 is an elevation view of embodiments of the invention in a tricolor shift configuration.
[0014] FIG. 8 is an elevation view of embodiments of the invention with a center portion having a separate color.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Reference is made to the Figures in which elements of the illustrated embodiments of the invention are given numerical designations so as to enable one skilled in the art to make and use the invention. The shading in the figures is used to identify color as described herein. It is understood that the following description is exemplary of embodiments of the invention and it is apparent to skilled persons that modifications are possible without departing from the inventive concepts herein described.
[0016] As described herein, the color champagne includes the typical color of the beverage champagne including pale tints of yellowish orange that are close to a beige color. The term silver includes the well known silver colors including a soft silver color and a hard silver color that includes tints of gray.
[0017] As shown in the Figures, a light reflector or umbrella 10 is shown supported on a support 12 in a conventional manner with an attached umbrella skin 14 . The umbrella 10 includes the parabolic reflectors known to persons skilled in the art. The umbrella 10 includes a center aperture 16 as shown in FIG. 1 for securing a light source thereto for use in stage, studio, motion picture and still photography.
[0018] In the embodiments shown in FIG. 1 , the skin 14 is arranged in a series of panels in stripes of alternating colors. The panels 20 , 22 , 24 , 26 , 28 , 30 , 32 , 34 , 36 , 38 , 40 and 42 are of one color and the odd numbered panels 21 , 23 , 25 , 27 , 29 , 31 , 33 , 35 , 37 , 39 , 41 and 43 are of a color different than the color of the even numbered panels. The even numbered panels are a white color and the odd numbered panels are a different color, including a black color, a champagne color or a silver color. In further embodiments, the even numbered panels are silver in color and the odd numbered panels are a black color or a champagne color. In additional embodiments, the even numbered panels are a champagne color and the odd numbered panels are black in color.
[0019] In FIG. 2 , the skin 14 is shown in a shift or shifted configuration from the configuration shown in FIG. 1 . Panels numbered 50 - 73 are arranged on the skin 14 as shown in FIG. 2 with the even numbered panels being of one color and the odd numbered panels a different color. The color combinations for the panels, include, but are not limited to, black and white, gold and white, silver and white and champagne and white. The panels numbered 80 - 103 are arranged on the skin 14 as shown in FIG. 2 with the even numbered panels being of one color and the odd numbered panels a different color. The same color combinations are available as for panels 50 - 73 . In embodiments of the invention, a panel that is diagonally adjoining a panel in a different ring of panels may be of the same or different color as the adjoining ring and all such color combinations are within the scope of the invention.
[0020] In embodiments illustrated in FIG. 3 , the panels numbered 110 - 133 are arranged on the skin 14 with the even numbered panels being of one color and the odd numbered panels: a different color. The color combinations for the panels, include, but are not limited to, black and white, gold and white, silver and white and champagne and white. The panels numbered 140 - 163 are arranged on the skin 14 as shown in FIG. 3 with the even numbered panels being of one color and the odd numbered panels a different color. The same color combinations are available as for panels 110 - 133 .
[0021] The panels 170 - 193 are arranged on the skin 14 with the even numbered panels being of one color and the odd numbered panels a different color. The same color combinations are available as for panels 110 - 133 and as for panels 140 - 163 . In embodiments of the invention, a panel that is diagonally adjoining a panel in a different ring of panels may be of the same or different color as the adjoining ring and all such color combinations are within the scope of the invention.
[0022] In FIG. 4 , the panels 200 - 211 of the skin 14 are of one color and the panels 212 - 223 are of one color that is different from the color of panels 200 - 211 . The color combinations for the different colored panels include, but are not limited to, black and white, gold and white, silver and white and champagne and white. For example, panels 200 - 211 are a black color and panels 212 - 223 are a white color in one embodiment.
[0023] In embodiments illustrated in FIG. 5 , the panels 224 - 246 of the skin 14 are of one color and the panels 248 - 270 are of a different color. The color combinations for the different colored panels include, but are not limited to, black and white, gold and white, silver and white and champagne and white. Also as shown in FIG. 5 , these embodiments include panels 225 - 247 which are of one color and panels 249 - 271 that are of a different color. The color combinations for the different colored panels include, but are not limited to, black and white, gold and white, silver and white and champagne and white.
[0024] In FIG. 6 , the skin 14 is shown in a tricolor configuration. In these embodiments, panels 271 - 294 are arranged in a striped configuration in three alternating colors. In one or more embodiments, the panel colors alternate from black, to silver and to white and in other embodiments, the panel colors alternate among hard silver, soft silver and white. However, the invention includes any combination of alternating colors.
[0025] In FIG. 7 , the skin is shown in a tricolor shift configuration. In these embodiments, the panels numbered 300 - 322 are arranged on the skin 14 with these panels alternating among three colors. The color combinations for the panels, include, but are not limited to, black, white, gold, silver and champagne. The panels numbered 323 - 346 are arranged on the skin 14 as shown in FIG. 7 with these panels alternating among three colors. The same color combinations are available as for panels 300 - 322 . The panels 350 - 373 are arranged on the skin 14 with these panels alternating among three colors. The same color combinations are available as for panels 300 - 322 and as for panels 323 - 346 . In embodiments of the invention, a panel that is diagonally adjoining a panel in a different ring of panels may be of the same or different color as the adjoining ring and all such color combinations are within the scope of the invention.
[0026] In FIG. 8 , the skin 14 is shown in an embodiment with the center portion 382 having a different color than the exterior portion 380 of the panels. The colors for the center portion 382 , include, but are not limited to, black, gold, silver and champagne. The colors for the exterior portion 380 include, but are not limited to, white, silver, gold and champagne.
[0027] While the present invention has been described with regards to particular embodiments, it is recognized that additional variations of the present invention may be devised by persons skilled in the art without departing from the inventive concepts disclosed herein and the invention is entitled to the full breadth and scope of the claims.
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Skins for light reflecting umbrellas. and for methods of using light reflecting umbrellas. The invention includes skins with a series of panels in stripes of alternating colors, in a shifted configuration, in a checkered shift configuration, in a half and half configuration, in a modified half and half configuration with a center portion having a separate color combination, in a tricolor configuration, in a shifted tricolor configuration and in a center black configuration.
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[0001] This invention refers to a floor and wall cleaner specially designed to be used in critical areas with difficult accessibility or restricted access, such as pools for housing a reactor vessel at a nuclear power station, in which human presence must be avoided as far as possible and, should this be necessary, this must be for the shortest possible time.
[0002] According to the invention, the floor cleaner comprises:
A casing or housing provided with a suction mouth; Drive belts on each side, driven by respective motors; Inner rollers, provided with mutually independent drive media; A set of outer rollers with permanent opposite rotation; At least one elastic hinge of at least one axle carrying the rollers; Gear motor assemblies for the roller movement A set of sealed connections and a first control body; Lighting systems; At least one camera for taking pictures; A float or buoy of variable volume; A set of turbines for gripping the wall; A set of turbines with lateral movement; and An anchorage for holding the float or buoy to the body of the casing or housing.
[0016] The pools in which the reactor of a nuclear power station is housed are made up of a cubicle which may be in a regular or irregular shape and have dimensions that can range from one or two dozen metres on the smallest horizontal side to several dozen metres on the larger side, with a height of several metres, able to temporarily house a large number of the components of the reactor in the dismantling stage.
[0017] The base of the pools tends to be of irregular shape. On one hand there are small-sized recesses which have to be cleaned preferably before emptying the pool, as these could contain radioactive material, and there are also uneven parts of the floor, amongst other reasons due to the bolts for holding the vessel of the reactor.
[0018] This thus requires a device for cleaning the floors of the pools in which reactors of nuclear power stations are housed which is able to clean narrow spaces, to the maximum width of the apparatus and which is able to get over any small obstacles which it might come up against.
[0019] As well as the floors, particles are deposited on the walls of these pools. Conventional devices are not nevertheless able to clean the walls, as if they did so it would be the suction force of the absorption system which would have to keep the device attached to the wall. Since these devices have to be made as far as possible of stainless steel or some other material able to be decontaminated, they have a high minimum weight, and the absorption systems conventionally used are not able to maintain their grip. Furthermore, even when the absorption capacity is enough to maintain a grip, any irregularity or space would cause loss of adherence, and the device would fall to the floor and have to be positioned again. Since the positioning task is extremely delicate, this risk in an installation of this sort makes such a system inoperative.
STATE OF THE ART
[0020] There are different types of floor cleaners. First of all there are manual cleaners, which have a rod with which the cleaning head is moved; this head is connected by means of a suction hose to a pump and normally to a filter to be returned to the pool. This type of cleaners cannot be used in the vessel of a nuclear reactor due to several problems:
The floor tends to be located more than ten metres below the surface and there is an even greater distance to the accessible upper edge; The pool may not have an upper perimeter strip from which the rod can be handled; The visibility of the floor from the height at which this must be handled is very limited or none at all. This requires a person to be handling the rod, which is not feasible through the height at which this is handled, the lack of visibility and the dose of radiation that the person in question would receive.
[0025] EP 1472425 describes an independent floor cleaner for pools which comprises a set of support wheels and is provided with filtration and pumping means. It does not have means of controlling the movement at will.
[0026] A robot device known on the market as “ZODIAC Sweepy M3”, comprises a pair of lateral drive chains driven by motors and also comprises a motor for pumping water through a filter. The cleaning width is nevertheless interior, between the drive chains, for which reason it ends far from the outer edges. Furthermore, since this is conceived for cleaning swimming pools, it is not designed to get over obstacles.
[0027] In the nuclear industry, the “WEDA N600” device is also a compact device able to be handled in remote control or in automatic mode, which has, like the previous one, a pair of drive chains, in this case with front and rear brushes of a width roughly equal to that of the body of the device and in which the extraction system installed in the apparatus itself expels the water through filter bags.
[0028] The “ATOX underwater bottom cleaner” device has a structure similar to the previous ones, in that this is provided with lateral drive chains, with a filtration body operated with an exterior pump. One major disadvantage of this device is its weight, apart from the difficulties of cleaning the side zones, for the reasons given above.
[0029] Other devices, even whilst complying with some of the characteristics described in the devices mentioned, are machines with a greater size, weight, cost and with the disadvantages also described above, without the manoeuvring capacity which is intended to be solved with this invention.
[0030] Furthermore, any of these can be held up by a small obstacle, such as a bolt head two or three centimetres high, when said obstacle is not directly confronted by one of the drive chains.
[0031] An automated pool cleaning vehicle has been disclosed by US 2012/102664 A1, with a housing defining an interior having a pump and a filter bag. The bottom is normally concave. It includes a first and a second pair of wheels connected to the chassis, and also at least a middle roller. Contrary to the teachings of the present invention where the central rollers have a cleaning function in addition to the translation function, the rollers in US 2012/102664 A1 do not have a cleaning (bristling) function but just a translation function, and operate to overcome some kind of obstacles such as steps in a swimming pool. Since it is not conceived for nuclear installations, plastic parts can be used creating a light weight, so the suction force can keep it adhered to the walls. When failure of adherence is encountered, for example when a void portion is found and the suction do not keep the vehicle attached to the wall, the vehicle falls down to the bottom of the pool. The structure therefore does not contain a floater to approximate the resultant density when submerged to that of the water, and have not government means which allow the device to be positioned in a desired position. The rollers are at traction device not having a rotatable roller cleaner different than the traction system
[0032] WO 2013/30005 A1 discloses a device for use in nuclear installations. Since it must be manufactured with metal parts it has a substantial high weight. It comprises a pump with a nozzle connected to it and arranged to face surfaces to be cleaned. It comprises adjustable flotation means. The floater as designed is not capable to keep the centre of gravity of the device, so when found an obstacle or a void portion in the pool which reduces the suction this device also falls down to the bottom of the pool or must be supported by an external crane.
[0033] There are light swimming pool cleaners made of plastic materials which are able to go up the walls of pleasure swimming pools, but which are not usable in the pool of a nuclear power plant reactor for the reasons stated above, since plastic is not an acceptable material for said use, and neither do they have devices for controlling their movement.
[0034] None of said devices is able to efficiently clean the walls of the vessel of a nuclear power plant reactor in a controlled manner.
[0035] It is furthermore desirable for the same apparatus which is able to clean the walls to be able to clean the floor. This has advantages in the cost of the device, since instead of two (one for the walls and one for the floor) one will be enough and the operations can be performed consecutively with no need to perform two decontamination processes; one of these is enough at the end of both operations, for cleaning the floor and the walls.
[0036] It is furthermore desirable for the same apparatus to be suitable for cleaning sloping surfaces.
DESCRIPTION OF THE INVENTION
[0037] The invention being proposed consists of a floor cleaner which comprises a structure carrying the other items, which are as follows:
A front roller; the front roller is held on a central support, securely held in turn to one of the side elements forming said structure; this roller is elastically hinged to said central support; it is divided into two halves or bodies, each of these being on one side of the central support; A rear roller, essentially identical to the front roller; A front central roller, preferably the front roller and the front central roller should be driven by a single motor, but they could also be driven by means of separate motors; A rear central roller; the rear roller and the rear central roller should preferably be driven by a single motor, but they could also be driven by means of separate motors; A suction bell placed on the casing, with an upper intake (on the side opposite that of the support for the rollers) and a linear suction mouth which is placed between the central rollers; Two sets of drive wheels or belts, one on each side, in which each set of drive wheels or belts is driven by an independent motor; it is preferable for the movement to take place by means of belts, as the possibility of the device being held up on an obstacle, such as a bolt head, is lower if this option is used. The pulling takes place by means of independent motors, with variable speed and rotation direction, meaning that, depending on the rotation direction of the motors, the cleaner can move forward when both belts rotate at the same speed in one direction, move in reverse when they rotate inversely in respect of the above or with displacement when the speeds of the belts are different.
[0044] For proper cleaning of the floor, there are central interior rollers and front and rear exterior rollers. In particular, according to the preferred embodiment, two interior rollers are used, with the suction bell between them, and two exterior rollers, each of these, the front and rear ones, being placed on a hinged support in a normally central position. The interior rollers have a smaller size than the width of the cleaner, insofar as these are driven from at least one of their sides and between the drive system. The outer rollers are divided into two portions, and driven from the centre, so that the free end of each side reaches the maximum width of the cleaner; in particular the length of the rollers is slightly greater than the width of the cleaner casing.
[0045] The rollers are made up of a core and a sheath. It has been found that an ideal sheathing for proper cleaning is made up of rubber strips, arranged radially (in a transversal direction to the movement). Hence, at least some of the strips will have to be positioned radially in respect of the roller axis. These transversal strips may be joined to strips arranged on a plane perpendicular to the axle of the roller without impeding their operation.
[0046] In normal operation, with no obstacles, the exterior rollers and interior rollers turn in a direction so as to move the dirt towards the interior of the suction bell, that is, they drag the dirt along the floor towards the interior of the suction bell. The displacement is caused by the drive belts. The movement of the front belts and of the rear belts in this normal operation will be in mutually opposite rotation directions; however, when they come up against an obstacle, one of the rollers may possibly have a support which exerts significant force, so that the movement inverse to its displacement could block the floor cleaner, without the drive belts having sufficient support. For this reason, since the front rollers and the rear rollers are driven by independent motors, in the event of their coming up against an obstacle, such as a bolt head or a drop or rise in level of some centimetres, all the rollers may be made to run in forward motion, that is, in the same rotation direction as the wheels or drive belts, which helps to get over the obstacle in question.
[0047] The movement of the rollers is separate from the displacement movement of the cleaner, and is driven by two independent motors, as has already been said. The control device can nevertheless synchronise the motors for optimum operation.
[0048] For the movement of the rollers and the drive belts, there are respectively motors and mechanical transmission assemblies, each formed of a plurality of pinions engaging each other.
[0049] As has already been stated, the exterior rollers are driven from the central part; this central drive is made up of an arm or support which houses a mechanism, and sustains the corresponding parts of the lateral roller projecting outward, up to a width slightly over that of the casing. This means that the exterior rollers do not properly clean a central zone in which the support and the drive mechanism for the front and rear rollers are located, which is why this zone has to be cleaned by the interior rollers. The sheath of the interior rollers must thus be continuous on the longitudinal plane on which the mechanism for driving the exterior rollers is located, especially the front rollers.
[0050] Throughout the cleaning process different obstacles may come up, such as screw heads, bolt covers, etc. These obstacles do not tend to be over 2 or 3 cm in height but no compact conventional system is able to overcome these without getting jammed. If the arm carrying the front or rear rollers were rigidly fixed to with the housing of the cleaner, this would make it jam, since on rising up the obstacle, it also undesirably raises the drive belts, and the device loses traction. For this reason it has been designed for both the front arm and the rear arm to have a hinged support, and be subject to an elastic retaining tension, so that the elevation tension is lower than the cleaner's effective weight in the water and so that when an obstacle is reached said arm rises over the obstacle and the cleaner continues its travel and after the obstacle is reached by the drive belts, these are indeed able to get over this with no further problems, the arm returning to the normal working position when the elastic tension caused on reaching the obstacle has been released.
[0051] Sometimes small obstacles are nevertheless located in the centre of the cleaner and are not reached by the drive belts. To solve this drawback, at least one of the rollers, and in particular all of these, have been provided with a set of wheels joined to their axle, so that when the cleaner comes up against an obstacle, these wheels continue to pull. The wheels have a smaller diameter than that of the corresponding brush, so that they will not have contact with the floor unless an obstacle with sufficient height is found. This guarantees that the cleaning is correct in routes with no obstacles. Since the rollers are driven by independent motors, two by two (one for the front ones and one for the rear ones) when an obstacle is reached which holds up the floor cleaner, all the rollers will rotate in the same direction, the wheels of said rollers thus pressing on the obstacle and easily getting over this.
[0052] According to a less preferred option for embodiment, the wheels of one of the rollers can be freely rotating, independently of the roller movement.
[0053] The alignment of the support wheels of the interior rollers with the position of the arm holding the mechanism for driving the exterior rollers should be avoided, insofar as said exterior rollers do not reach the position of said supporting arm.
[0054] The suction head is placed held on the cover of the structure, and comprises an upper suction mouth which is connected to a suction pump, either directly or through a conduit; if this is joined to a conduit, a connector is provided, freely rotating at both ends and in a central zone also at 45°, allowing the positioning of the conduit with no restriction both from the upper head and from any lateral position.
[0055] The structure is made up of lateral elements and means of joining said elements; it also comprises an upper cover holding the suction head, and protectors or covers at the front and rear, essentially symmetrical except for the holes for the corresponding connectors. The structure is closed at the front and rear by the corresponding rollers. According to one option each of the lateral elements is formed of a pair of separate parallel plates which define a chamber housing mechanical transmission and possibly drive assemblies.
[0056] Even when a turbine has been used for the cleaner to grip the floor in embodiments prior to this invention, this is insufficient. Furthermore, since the suction bell is in a central position, a turbine has to be displaced from said centre, and although this is not critical in cleaning floors, it causes unwanted imbalances when this has to clean walls, which could make the cleaner fall to the floor, requiring further repositioning. The floor and wall cleaner of the invention is thus provided with at least a pair of turbines, which may run simultaneously or independently. The use of turbines for adherence placed symmetrically in respect of the longitudinal and/or transversal central plane has been shown to have a satisfactory result, which cannot be achieved with a single one.
[0057] Since the device may be used in a dark zone, such as the pool of reactor vessel at a nuclear power plant, the cleaner is designed to have lighting means, at least in the forward motion direction, but possibly also for reverse movement.
[0058] It is also designed for this to have at least one camera and possible two, one at the front and one at the rear, so that the state of cleaning achieved can be known at all times as well as the directions to be taken.
[0059] One of the problems for keeping the cleaner on a wall is the weight of the device. As already stated, plastic materials cannot be used in operations in radioactive zones, for which reason the cleaner has a significant weight, of several dozen kilograms.
[0060] For this reason the casing has been provided on both sides with two supports for joining this to a float. The float has the aim of compensating part of the cleaner's weight. In particular, it has been designed to have a pair of supports on each side, so that when only walls have to be cleaned, the alignment of the float is roughly over the centre of gravity of the cleaner. When this has to clean sloping surfaces the anchorage could nevertheless be hinged, or arranged in any other position.
[0061] The float comprises a normally prismatic sealed body, with a fixed volume, when the apparatus is operating. This sealed body can also comprise an inflatable interior membrane. It is designed to have inlet/outlet valves for cleaning or ballast, normally with water, when the volume required for the specific application is lower than the total volume of the chamber. This float exerts an upward force of from 40% to 90% of the weight of the cleaner, according to the design specifications, apart from overcoming its own weight. Furthermore, to regulate proper operation of the ascending and descending operations it has also been designed for the body to be provided with a second chamber fitted with an inflatable membrane, with a variable body which totally neutralises the weight of the body or even which makes this float. This second chamber is made with perforated sheet metal, so that when the membrane inflates, any water found inside said second chamber can easily be drained out.
[0062] The cleaner comprises an electronic control system. The electronic control system determines the actions of speeds and movement directions of each of the motors for driving the displacement or movement of the rollers and the turbine, of the lighting and picture-taking elements, or indicates any fault which might arise in the device. The electronic system comprises a sealed connection plate for connecting electric supply and control cables of the device.
[0063] The control body is placed outside the device, and joined to this by means of supply cables for the different elements, insofar as it been shown that the radiation received in the pool quickly disables some of the functions. The governing system is normally placed in a remote control unit, which is normally a computer. This could possibly have an intermediate unit, for example a float which minimises the requirements of control cable sections, when the distances are too long, and which also enables control by means of wireless means.
BRIEF DESCRIPTION OF THE DRAWINGS
[0064] In order to illustrate the following explanation, ten sheets of drawings are attached to this descriptive report, representing the essence of this invention in eleven figures, and in which:
[0065] FIG. 1 shows a general schematic view in perspective of the floor and wall cleaner of the invention, not including the float;
[0066] FIG. 2 shows a general schematic view in perspective of a float able to be connected to the floor and wall cleaner of the invention;
[0067] FIG. 3 shows a general schematic view in perspective of the floor and wall cleaner assembly of FIG. 1 with the float of FIG. 2 ;
[0068] FIG. 4 shows a schematic front view of the floor and wall cleaner of the invention not including the float;
[0069] FIG. 5 shows a schematic view along a central longitudinal section of the floor and wall cleaner of the invention not including the float;
[0070] FIG. 6 shows a schematic lower view of the floor and wall cleaner of the invention, not including the float;
[0071] FIG. 7 shows a schematic view in perspective of the suction bell which is fitted in the cleaner;
[0072] FIG. 8 shows a schematic exploded view of an example of an embodiment of one of the interior rollers;
[0073] FIG. 9 shows a schematic exploded view of an example of one of the exterior rollers, with a body for securing to the chassis and an elastically hinged arm for holding said rollers;
[0074] FIG. 10 shows a schematic view in perspective of the flat development of one form of covering the rollers;
[0075] FIG. 11 shows a section view of a cleaning roller provided with the sheathing of FIG. 10 ; and
[0076] FIG. 12 shows a schematic view in perspective of a scraper fitted on the float.
[0077] The following reference numbers are used in said figures:
1 upper cover 4 gripping turbines 8 turbine or autonomous external suction pump 11 lateral elements 12 front and rear covers 30 suction mouth or nozzle 51 front exterior cleaning roller 52 rear exterior cleaning roller 53 front interior cleaning roller 54 rear interior cleaning roller 55 traction device 56 roller sheathing 100 drive and cleaning body 121 engagement opening 150 suction bell 151 rectangular section of the suction bell 200 floatation body 201 casing or housing of the floatation body 202 coupling arms of the floatation body 203 securing holes of the coupling arms 204 lateral turbines of the floatation body 205 second variable volume chamber 206 connection of the second chamber 210 scraper 211 soft strip 212 sustaining part 521 pivot axis of the exterior arms 525 support of the exterior rollers 526 hinged arm of the support of the exterior rollers 527 spring of the hinged arm 538 core of the interior roller 539 support wheels of the rollers 551 pulleys of the drive device 552 drive belt 558 transmission items 559 drive motor 561 lamellae of the roller housing
DESCRIPTION OF THE FORMS OF EMBODIMENT OF THE INVENTION
[0115] The invention being proposed consists, as stated in the heading, of a floor and wall cleaner, governed by remote control, suitable for use in cleaning the floors and walls of the pools housing the vessel of nuclear power stations.
[0116] This is made up of a drive and cleaning body ( 100 ) and a floatation body ( 200 ).
[0117] The drive and cleaning body ( 100 ) is mainly made up of components of stainless steel and comprises the following elements:
Lateral elements ( 11 ), joined together to form a structure; according to a preferred embodiment the lateral elements ( 11 ) are made up of a double wall on each of their sides, inside which transmission elements ( 558 ) are housed; An upper cover ( 1 ) provided with a suction mouth ( 30 ); Front and rear covers ( 12 ); at least one of these will normally be provided with an engagement opening ( 121 ), made in the end emerging over the upper cover ( 1 ); A traction device ( 55 ); the traction device is made up of at least one drive motor ( 559 ) with adjustable speed on each side of the drive and cleaning body ( 100 ); normally each of the sides will have a gear motor mechanism for distributing the movement to a pair of pulleys ( 551 ), one front and one rear, which sustain and move a drive belt ( 552 ) or band or chain. The drive motors ( 559 ) as well as the transmission mechanisms are independent on each of the sides and are governed by a control system which could determine whether one or both move, the speed of the movement and the rotation direction, so as to enable the following states:
The cleaner is at rest, when the motors ( 559 ) are idle The cleaner moves in a forward direction, with a variable speed depending on the rotation speed of the motors ( 559 ), synchronized by the control body; The cleaner will rotate, by inverting the rotation direction of the motors ( 559 ) for a static rotation, or by variation of the speed of one of the motors in respect of the other, when the rotation takes place while moving;
Hence, an axle moved by the drive motor ( 559 ) transmits the rotation movement to each of the sides, and a mechanical system of gears (transmission elements 558 ) transmits this to at least one of a pair of pulleys ( 551 ) or drive crown wheels set on the corresponding side; the movement is preferably transmitted to the two front and rear pulleys or crown wheels on each of the sides; the belt ( 552 ) may have a toothed interior matching the outside of the pulleys ( 551 ), so as to guarantee absolute control of the movement with no unwanted sliding; A set of cleaning rollers ( 51 , 52 , 53 , 54 ), the rollers are made up of a core ( 538 ) and a sheath ( 56 ); the sheath is made of an elastic material, such as rubber, formed of or comprising in its outer surface at least one set of tabs or lamellae ( 561 ) arranged in a radial position, i.e. transversal in respect of the rotation direction; said lamellae ( 561 ) may be complemented by others arranged in planes transversal to the roller axis ( 51 , 52 , 53 , 54 ), or in other directions, this cleaning roller assembly comprises:
Exterior cleaning rollers ( 51 , 52 ) which are located at the front and rear edges of the casing; Interior cleaning rollers ( 53 , 54 ) which are located inside the casing, between the drive belts or between the lateral elements ( 11 ) which sustain these; The front rollers ( 51 , 53 ) are driven by means of a single motor which transmits the movement to the motor axles of both of these by means of the corresponding transmission mechanism, but, within the scope of the invention, they could also be driven by means of independent motors; and the rear cleaning rollers ( 52 , 54 ) are driven by means of a single motor which transmits the movement to the motor axles of both of these by means of the corresponding transmission mechanism, but they could also be driven, within the scope of the invention, by means of independent motors; In the ordinary cleaning operation, on flat surfaces or with fairly low obstacles, the front (exterior and interior) rollers and the rear (interior and exterior) rollers will rotate in opposite directions, dragging the dirt towards the centre of the device; there are nevertheless times at which it is necessary to get over an obstacle of some height; for this purpose the exterior rollers are arranged on a support ( 525 ) with an elastically hinged arm ( 526 ) which tends to be placed in the lower position, for cleaning, but which is able to rise against the elastic force when an obstacle forces it to do so; also in view of any change in position of the cleaning device, particularly through its forward or backward tilting, it has been seen that it is useful for the rear exterior roller also to be arranged on an elastically rotated arm ( 526 ); it has nevertheless been designed for the cleaning of smooth surfaces, especially walls, that the arm ( 526 ) can be secured to prevent any movement; a securing pin is enough to do this; The rollers will normally rotate in opposite directions, dragging the dirt towards the suction zone; to assist in getting over obstacles, it is nevertheless designed for the rollers to be able to all turn in the same direction as the drive means; The width of the interior rollers is thus limited by the width of the casing; it is nevertheless a requisite for the cleaning to be carried out at the maximum width of the devices, without a wall or any other similar obstacle being able to limit the lateral cleaning capacity; for this reason the exterior cleaning rollers ( 51 , 52 ) reach the required width on the outside, at the limit of or outside the width of the device; for this purpose they are fitted on respective central arms ( 526 ) which support these, and which have the corresponding transmission mechanisms, with the cleaning roller ( 51 , 52 ) formed of two separate portions and sustained only by its central part (by one end of each of the portions); in accordance with one option, the separate portions may be independently sustained, so that the corresponding arm ( 526 ) is independent for each side, and in the event of there being any type of hinge of said arm ( 526 ) the axis of the two portions could become out of alignment; said option is not nevertheless considered preferential due to its mechanical complexity, even though it is considered within the scope of the invention; as a general rule, the two front and rear arms are elastically hinged so that they can pivot on respective axles ( 521 ) located in the body of the casing ( 1 ); when an obstacle is reached the elastic retaining of the arm ( 526 ) which keeps this in a position aligned with the floor (as for the rest of the rollers) is overcome, so that the arm allows the cleaning roller ( 51 , 52 ) which this sustains to rise, thus preventing the cleaner from becoming jammed on said obstacle; in FIG. 9 , one can see a configuration of the hinged arm ( 526 ) with elastic retention by means of a spring ( 527 ), the power shafts for the movement are represented and in a preferential embodiment the support ( 525 ) of the arm ( 526 ) is normally held to just one of the lateral elements ( 11 ) of the structure; the interior rollers ( 53 , 54 ) have a core made up of a single continuous rigid body, and their sheathing divided into portions and the drive mechanism is placed on at least one of their sides; on the other hand, the exterior rollers ( 51 , 52 ) are divided so that these have two external portions, with a central drive mechanism in the arms ( 526 ) which constitute the sole support of each of said portions; The housing of the interior rollers ( 53 , 54 ) is made up of several portions, between which there are one or more support wheels, with movement linked to the roller on which these are located, or free in respect of this, in a less preferred embodiment; it is intended for the support wheels ( 539 ) of the interior rollers not to be aligned with the wheels ( 526 ) and drive mechanisms for the exterior rollers, in which there is no exterior cleaning, and these are not aligned either with the support wheels ( 539 ) of the other of the interior rollers; The exterior rollers also preferably have support wheels ( 539 );
The casing ( 1 ) also comprises at least one pair of gripping turbines ( 4 ); the gripping turbines ( 4 ) take the water from the outside of the casing and drive this in normal direction (perpendicular) and in the opposite direction to the support surface of the rollers (normally horizontal); the greater the discharge force (flow, speed), the greater the adherence to the surface will be; in particular there are two turbines located on the longitudinal symmetry plane and symmetrically in respect of the transversal symmetry plane; The structure also comprises, according to a preferred option, a suction turbine or pump ( 8 ) (represented in FIG. 4 ), independent and linked with the suction mouth ( 30 ); the suction turbine or pump ( 8 ) is set on the outside of the suction mouth ( 30 ), integrated in the cleaner, allowing independent operation with no need for any external suction source; it can be provided with filtration media or not; The casing ( 1 ) comprises a suction mouth ( 30 ); in the event of this having to be connected to an external inlet with a suction tube, said suction mouth will be provided with rotating elements and with a rotation body at a 45° angle; The casing ( 1 ) also comprises at least a light source and a camera for taking pictures; The casing ( 1 ) is provided with a sealed connection plate or sealed connectors; the cleaner comprises a control and governing body; due to the sensitivity of the semi-conductors to radiation, it is intended for the control body to be placed outside the device, preferably outside the intense radiation zone, and joined to this from the outside (in the area around the pool) by means of connection cables; this control and governing body will provide remote control for each of the elements controlled, such as stop-start and speeds and direction of rotation of each of the motors, as well as the light, camera, turbines, etc. The upper cover ( 1 ) holds a suction bell ( 150 ); in its upper portion it forms the suction mouth ( 30 ), and in the lower zone it forms a rectangular section ( 151 ) set between the interior rollers at the height of the geometrical plane joining their corresponding axes.
[0143] In this configuration, the drive and cleaning body ( 100 ) has a maximum width of roughly 32 cm and a length of roughly 41 cm, and has a floatation body roughly 90 cm long, which allows great manoeuvring capacity and can reach recesses which would be impossible for other devices due to their dimensions and structure.
[0144] To give the cleaner the required floatability to be able to move along a wall or sloping surface, normally from the top downwards, it has been designed for said cleaner to comprise a floatation body ( 200 ). The floatation body ( 200 ) is formed of a casing or housing ( 201 ) with at least one first sealed chamber, which can also be provided with an interior inflatable membrane. This first chamber is provided with inlet/outlet connections for filling/emptying and interior cleaning. This will normally be full of air, but in some applications, or to be used with a lighter body, it may be partly full of water, the rest being air, which means that the float force can be regulated. The floatation body ( 200 ) is provided with coupling arms ( 202 ) on both sides of one of its ends. These coupling arms ( 202 ) comprise at least two holes ( 203 ) or means of connection to other corresponding ones on the outer walls of the lateral elements ( 11 ). These arms will preferably hold the lateral walls by means of securing screws in all their holes. However, especially when used for cleaning sloping surfaces, the arms will be secured with a single screw on each side, allowing the floatation body to tilt ( 200 ) in respect of the drive and cleaning body ( 100 ), held by the coupling arms ( 202 ).
[0145] The floatation body comprises lateral impulsion turbines ( 204 ). In a preferential embodiment, the lateral impulsion turbines ( 204 ) are attached to the coupling arms ( 202 ), along with the first chamber ( 201 ). The activation of these turbines when the cleaner is in a state of weightlessness through the compensation of the weight with the corresponding floating force will enable a lateral displacement to a new cleaning position. The turbines for securing the cleaner body will return the cleaner to the surface of the wall so that the assembly has free travel in all degrees since it is provided with forward and reverse movements, rotation, gripping and withdrawing from the surface to be cleaned, and lateral displacement.
[0146] According to a preferential embodiment, the floatation body ( 200 ) also comprises a second chamber ( 205 ) with variable volume, provided with an interior inflatable membrane. Filling/emptying said second chamber ( 205 ) with air is done by means of a connection ( 206 ) to an external compressor. Depending on whether greater or lesser floatation of the cleaner is needed, the variable volume chamber will be totally empty, thus meaning that the effective weight of the cleaner will be the maximum or will be partly full, or totally full of air, and the effective weight will therefore be the minimum. The second chamber comprises at least one perforated wall, so that when the inner balloon inside this is filled (totally or partly) with air, the water that the volume of air displaces can be drained out. According to a particular embodiment, the first fixed volume chamber and the second variable volume chamber constitute a prismatic body to which the coupling arms ( ) are linked; the chamber with variable volume is preferably located in the portion furthest from said prismatic body.
[0147] Furthermore, insofar as the floatation body ( 200 ) will when cleaning walls always be located at the top of the drive and cleaning body ( 100 ), it has been designed for the floatation body ( 200 ) to be provided in the portion furthest from said drive and cleaning body ( 100 ) with a scraper ( 210 ). The scraper is formed of a soft strip ( 211 ), normally made of rubber, arranged on a holding part ( 212 ); in accordance with a preferential embodiment this support is made up of a tube with circular section made of a light material and filled with injected foam, thus minimizing its density and constituting a further floating part. In a preferred embodiment, the holding part is set on one or more supports joined to the floatation body ( 200 ) which allow the scraper to take up different angular positions, modifying the distance to the wall in the same way in accordance with operating requirements.
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A cleaner includes an external casing forming a suction hood, an upper suction mouth, the casing also being provided with a drive arranged on each side and equipped with independent motors and corresponding transmission mechanisms on each side, and cleaning rollers; sets of internal cleaning rollers disposed close to the center of the hollow interior of the casing and having a width approximately equal to the distance between the side elements of the casing; sets of external cleaning rollers located close to the front and rear edges of the casing of the cleaning device and having a total width slightly greater than the width of the casing; a resilient joint at the support for the external rollers; a pair of adhesion turbines; auxiliary drive wheels on the internal cleaning rollers; a flotation body connected to the casing and having a fixed and/or variable volume; and laterally mobile turbines.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present Application claims the benefit of priority as a continuation of co-pending U.S. patent application Ser. No. 11/515,080. titled “Vehicle Barrier System” filed on Sep. 1, 2006, which is a continuation-in-part of U.S. patent application Ser. No. 10/897,417, titled “Vehicle Barrier System” filed on Jul. 21, 2004, which issued on Oct. 31, 2006 as U.S. Pat. No. 7,128,496, the disclosure of which are hereby incorporated by reference.
FIELD
[0002] The present invention relates to an installed vehicle barrier system that protects at-risk sites from vehicle born attacks. The present invention of the barrier system uses a combination of a number of vehicle attenuating devices to prevent the passage of vehicles. These devices include a traffic control zone, followed by a first impact element that is backed by a bed of deformable material, and followed by a second impact element.
BACKGROUND
[0003] Barriers for restricting the passage of vehicles (such as automobiles, trucks, busses, airplanes and the like) are generally known. Barriers that are fixed in the roadway, meaning they do not move by device or mechanism, are typically categorized as “passive” or “inoperable” barriers. These types of barriers are either removably placed on the roadway or sidewalk surrounding an at-risk site, or they are installed into the ground or built into the landscape/streetscape. Known installed “passive” barriers typically include foundation walls (typically at least 36″ high), or bollards in the form of “posts” embedded in a concrete foundation, and beds of a crushable material (such as concrete). Walls and bollards are intended to stop vehicles through impact resistance, having sufficient shear strength to remain intact at impact and relying on the inertia of their foundations to bring a vehicle to a halt.
[0004] In addition to vehicle barrier systems, vehicle arresting systems are also known. Where vehicle barrier systems are intended to immediately stop a vehicle, vehicle arresting systems are intended to control the stopping of a vehicle over a given time and/or distance. Known arresting systems include beds of a crushable material (such as concrete), fences and gates, and cable and elastic (e.g. “bungee cord”) systems. Crushable beds tend to utilize the interaction between the bed and the tire(s) of the vehicle. As a vehicle moves across the crushable material, the weight of the vehicle causes it to sink into the bed. At the same time, the spinning of the tire “rips” through the crushable material. As the vehicle drops farther into the bed, the tires' rotation tends to become slower until finally the vehicle is stopped. For example, crushable beds at the ends of aircraft runways for aircraft that “overshoot” the runway are generally known for gradually decelerating the aircraft over an extended distance to minimize injury to occupants and damage to the aircraft. Examples of such crushable bed systems are described in U.S. Pat. Nos. 5,885,025; 5,902,068 and 6,726,400.
[0005] These known vehicle barriers present a number of functional problems. Walls significantly impede pedestrian traffic and can cause pedestrian “herding” and “bottle necking.” Additionally, walls, and bollards as well, are somewhat visually restricting. The inherent height of the two, that is necessary for their function as a vehicle barrier, reduces the visual “openness” of the landscape/streetscape. Crushable beds are not optimal because they typically require an extended length of the crushable bed (upwards of 50 feet or more) to arrest a vehicle (and substantially longer for aircraft and the like). Such long lengths are generally not compatible with most urban applications, where space between a roadway and a building line or perimeter line is fairly small (e.g. 5-30 feet) and a primary objective of the barrier is to stop the progress of the vehicle within a relatively short distance. Such known vehicle barrier systems tend to provide limited application and flexibility to designers in providing an effective vehicle barrier system intended to meet applicable government performance standards, and is minimally obtrusive, for use in areas such as urban settings that typically have limited space for installation of such barriers.
[0006] Accordingly, it would be desirable to provide an installed vehicle barrier system or the like of a type disclosed in the present Application that include any one or more of these or other advantageous features:
1. A system providing a barrier that is resistant to unauthorized breach by vehicles. 2. A system that minimizes the restriction of pedestrian traffic flow. 3. A system that provides a less visually obtrusive installed vehicle barrier system. 4. A system that stops a vehicle in the short distance between a roadway and the protected site. 5. A system that rapidly arrests a vehicle without regard to vehicle damage. 6. A system that is integrated into the landscape/streetscape, employing similar elements such as curbs, sidewalks, benches, etc. 7. A system that combines a trafficable roadway surface, a curb, a bed of compressible material covered by a surface cover layer, and a low wall line or low bollard line. 8. A system in which the required height of the impact element line is interdependent with the characteristics of the bed of compressible material, so that the various components of the system may be adjusted to suit the needs of a particular application.
SUMMARY
[0015] One embodiment of the present invention relates to a barrier system for use between a roadway and a site requiring protection from advancing vehicles. The system includes a trafficable surface and a first impact element (such as a “curb” as typically included along an edge of a trafficable surface). The trafficable surface may include certain features to reduce the speed of an approaching vehicle before reaching the first impact element. Such features include frictional elements and barriers arranged to create traffic flow patterns. Vehicles that reach the first impact element will have their trajectory redirected upwardly from impact with the curb. Beyond the first impact element is a deformable bed intended to lower the elevation of a vehicle that encounters the bed by including a material or infrastructure configured to collapse, breakaway, crush, compress, yield or otherwise deform under the weight of the vehicle when the vehicle descends onto the bed after impacting the first impact element. The bed may be contained in a confining structure such as a foundation and topped by a surface cover layer at a substantially equivalent elevation with the top of the first impact element, configured to spread the weight of loads due to pedestrian and the like. Beyond the bed a second impact element in the form of an impact element line extends upwardly from grade level, separating the barrier system from a protected zone adjacent to a site requiring protection. The components of the system may be flexibly adapted in various combinations to suit installation in a particular application while providing performance that is consistent with applicable barrier performance standards.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a schematic representation of a top view of the vehicle barrier system according to an embodiment.
[0017] FIG. 2 is a schematic representation of a sectional view of the vehicle barrier system according to the embodiment of FIG. 1 .
[0018] FIG. 3 is a schematic representation of a sectional view of a vehicle impacting the first impact element of the vehicle barrier system of FIG. 1 and FIG. 2 .
[0019] FIG. 4 is a schematic representation of a sectional view of a vehicle jumping as a result of impacting the first impact element of the vehicle barrier system of FIG. 1 and FIG. 2 .
[0020] FIG. 5 is a schematic representation of a sectional view of a vehicle entering the compressible bed of the barrier system of FIG. 1 and FIG. 2 .
[0021] FIG. 6 is a schematic representation of a sectional view of a vehicle impacting the impact element line of the barrier system of FIG. 1 and FIG. 2 .
[0022] FIG. 7 is a schematic representation of a top view of the vehicle barrier system according to another embodiment.
[0023] FIG. 8 is a schematic representation of a sectional view of the vehicle barrier system according to the embodiment of FIG. 7 .
[0024] FIG. 9 is a schematic representation of a top view of a vehicle barrier system according to another embodiment.
[0025] FIG. 10 is a schematic representation of a sectional view of the vehicle barrier system according to the embodiment of FIG. 9 .
[0026] FIG. 11 is a schematic representation of a sectional view of a variation of the vehicle barrier system according to the embodiment of FIG. 9 .
[0027] FIG. 12 is a schematic representation of a sectional view of another variation of the vehicle barrier system according to the embodiment of FIG. 9 .
[0028] FIG. 13 is a schematic representation of a sectional view of another variation of the vehicle barrier system according to the embodiment of FIG. 9 .
[0029] FIG. 14 is a schematic representation of a sectional view of another variation of the vehicle barrier system according to the embodiment of FIG. 9 .
[0030] FIG. 15 is a schematic representation of a sectional view of another variation of the vehicle barrier system according to the embodiment of FIG. 9 .
[0031] FIG. 16 is a schematic representation of a sectional view of another variation of the vehicle barrier system according to the embodiment of FIG. 9 .
DETAILED DESCRIPTION
[0032] According to the illustrated embodiments, the vehicle barrier system provides an arrangement or combination of installed, vehicle arresting and barrier devices to be used along a security perimeter to create an area 5 protected from vehicle intrusion (e.g. to provide protection of facilities, buildings, restricted areas, etc.). This arrangement of vehicle arresting and barrier devices is intended to stop vehicles within a relatively short distance traveling at varying rates of speed, according to pre-established crash barrier rating systems and/or criteria. The vehicle barrier system is shown composed of a combination of distinct regions (shown for example as four regions). A vehicle attempting to breach the security perimeter may progressively encounter all four of these regions and each region, in turn, is intended to reduce the vehicle's speed or control the vehicle's approach and thus reduce its speed.
[0033] A first region includes a trafficable surface (e.g. asphalt, concrete, paving, etc.) using friction and/or traffic patterns to slow the vehicle (e.g. traffic patterns, friction elements, etc.), as the surface material can have a higher coefficient of friction than a traditional asphalt roadway. After encountering the first region, the vehicle may encounter a second region.
[0034] The second region includes an upwardly extending first impact element 2 (e.g. a fixed barrier, or vertical element, shown for example as a “curb,” etc.) disposed at the edge of the trafficable surface 1 or other desired location. The curb 2 is intended to reduce the vehicle's speed through inertial impact resistance. The curb 2 also serves to cause the vehicle to be directed at least partially upward (e.g. “jump”), where the vehicle's front wheels temporarily lose contact with the trafficable surface as the vehicle's trajectory is redirected upwardly from the impact with the curb. After the vehicle impacts the curb 2 , the vehicle moves upward and forward and descends upon a third region.
[0035] The third region includes a deformable zone 3 . The deformable zone 3 is intended to lower the elevation of the vehicle below the top of curb 2 by providing a bed 9 having an infrastructure or material that is configured to collapse, breakaway, crush, compress, yield or otherwise deform under the weight of the vehicle when the vehicle descends onto the bed after impacting the curb (see FIGS. 5-6 ). According to a preferred embodiment, the bed 9 of the deformable zone 3 has a length 15 within a range of one foot to thirty feet, and a depth 17 having any suitable depth for containing a deformable infrastructure or material intended to lower the elevation of a vehicle that encounters bed 9 by a sufficient amount so that a structural portion of the vehicle contacts the impact element line in the event that the vehicle traverses the entire length 15 of bed 9 . However, the length and depth may have any suitable dimensions for use in combination with a curb 2 and impact element line 4 for installation in a particular application. The deformable zone 3 is shown to include a cover surface layer 7 (e.g. paving, concrete, sedum, planting, soil, etc.) disposed on the surface of bed 9 . The cover surface layer 7 is intended to spread relatively smaller bearing loads (e.g. pedestrian, horse, carts, handtrucks, etc.), so as not to substantially deflect (or otherwise fail) under such loads or deform the deformable infrastructure or material of bed 9 below. The cover surface layer 7 is designed to fail under higher bearing loads and higher impact loads resulting from vehicles (e.g. automobiles, trucks, buses, etc.) having a sufficient weight (e.g. weighing at least approximately 2,500 lbs, and either crack (in the case of, for example, concrete, paving, etc.) or deflect (in the case of, for example, sedum, planting, etc.) so that the vehicle's weight bears on the deformable infrastructure or material of bed 9 below.
[0036] According to a preferred embodiment, the bed 9 comprises a deformable structure (e.g. lattice, honeycomb, etc.) constructed of metal, polycarbonate, plastic, composite metal, wood, etc. and configured to breakaway, collapse, crush, sink or otherwise deform under the weight of the vehicle. The bed 9 may also comprise a material (e.g. uniform or composite), alone or in combination with a structure, having characteristics that permit the material to crush, compress, yield, displace, or otherwise deform, such as, for example, cellular concrete, metallic foam, synthetic foam, or any other suitable material of combination of such materials, having a predefined compression strength, sufficient to crush under a tire(s) of a vehicle weighing at least approximately 2,500 pounds (lbs). The vehicle's weight combined with the rotation (e.g. “spinning” etc.) of the vehicle's tires is intended to deform (e.g. collapse, crush, compress, yield, displace, etc.) the deformable structure or material 9 , so that the elevation of the vehicle “drops” or is otherwise “lowered.” The deformation of the structure or material of bed 9 tends to lower the effective height of the vehicle, as the elevation of the vehicle decreases (e.g. sinks, falls, etc.) into the bed 9 , as well as reducing the vehicle's speed, due at least in part to the friction between the tires and the compressible structure of material. The desired deformability (e.g. strength, compressibility, etc.) of the structure or material of bed 9 will generally be determined by the length 15 of bed 9 and the height 16 of the impact element line 4 (shown for example as a low wall, etc.) backing the bed, on a case-by-case basis considering the available length for placement of the bed and the available height for the impact element line 4 . For example, if the area available for the bed is relatively short, then there will be a relatively small “drop” in elevation of the vehicle within the bed (as the vehicle traverses the length of the bed) and the impact element line 4 (e.g. wall, bollard, etc.) should be relatively high (e.g. sufficient to contact a structural portion such as a chassis of the vehicle, accounting for the relatively small drop in elevation of the vehicle within the bed). Conversely, if the area available for the bed is relatively long, then there will be a correspondingly greater “drop” in elevation of the vehicle within the bed (as the vehicle traverses the length of the bed) and the impact element line (e.g. a wall, bollard, etc.) may be correspondingly lower (or in certain cases, for example, essentially non-existent) such that the height or elevation of the impact element line 4 remains sufficient to contact the chassis of the vehicle to prevent further progress of the vehicle into the protected zone 5 .
[0037] The deformable zone 3 of the third region also includes a confining structure 8 for containing the bed 9 . The confining structure (e.g. a concrete foundation, metal trough, wood form-work, fabric mesh, etc.) is shown to surround the deformable structure of material of bed 9 , holding it in place, so that when the bed 9 is “loaded” it deforms and the deformed structure of material of the bed 9 is generally contained by the confining structure 8 . After encountering the third region having the deformable zone 3 , the vehicle may encounter a fourth region in the even that the vehicle traverses the length 15 of bed 9 .
[0038] The fourth region is shown located beyond the compressible zone, and includes an impact element line 4 . The impact element line (comprised of, for example, walls, bollards, posts, planters, projections, obstacles, etc.) is shown to have a sufficient height to impact a structural portion (e.g. the chassis, etc.) of the vehicle once the vehicle has dropped in elevation due to deformation of bed 9 of the deformable zone 3 . The resistance provided by the impact element line 4 is intended to be sufficient to stop any consequential progress of the vehicle after encountering the trafficable surface 1 , the curb 2 , and the bed 9 , so that the vehicle does not enter the area 5 to be protected.
[0039] In the wall or line construction of conventional vehicle barriers (e.g. “anti-ram” type, etc.) impact elements are typically specified as having a height of approximately three (3) feet tall, above a finish grade elevation. For example, in the case of the U.S. Department of State (DOS), a generally recognized national authority on vehicle barrier rating and authorization, “passive anti-ram” type impact barriers are specified to have heights within the range of 30-39 inches tall, (such as described in DOS design specifications DS-1, DS-7, and DS-50 for use with a “rigid” trafficable surface (e.g. roadway, etc)). According to the illustrated embodiment of the present invention, the height 16 of the impact element line 4 may be “lowered” or reduced by an amount corresponding to the deformability (e.g. compressibility, etc.) characteristics of the bed 9 . The greater the deformability of the material, the greater the degree of deformation and corresponding “drop” in elevation of the vehicle when the vehicle encounters bed 9 . As the bed's capability to deform (e.g. collapse, breakaway, compress, crush, yield, etc.) and thus lower the elevation of a vehicle increases, the height 16 of the impact element line 4 necessary to contact the chassis of a vehicle tends to decrease. The deformability of bed 9 serves to lower the effective height of a vehicle prior to encountering the impact element line 4 . As the approaching vehicle encounters the bed 9 , it drops below the grade of trafficable surface 1 or the height of curb 2 (based on a particular application), as its wheels “grind” through or deform the structure or material of bed 9 and the vehicle's inherent weight causes the material to deform under the bearing load of its wheels. As a result, in the event that the vehicle has traversed the length 15 of bed 9 and reached the impact element line 4 , the elevation of the vehicle has been lowered in relation to the finish grade and the height 16 of the impact element line 4 . The reduction in elevation of the vehicle is believed to be attributable to the length 15 of bed 9 and to the strength characteristics (e.g. yield, compressibility, deformability, etc.) of the structure or material of bed 9 .
[0040] According to a preferred embodiment, the length 15 of bed 9 , and the deformability of the structure or material and the height 16 of the impact element line 4 are related in an interdependent relationship and may be combined in a wide variety of combinations and permutations to accomplish the intended objective of providing an effective barrier system that is suitable for use in locations with reduced space and that provides an aesthetically and architecturally pleasing appearance. As previously described, a typical minimum height of a conventional “anti-ram” type impact element for use in connection with a conventional roadway is approximately three (3) feet. The use of the bed 9 in connection with the curb 2 and the impact element line 4 permits the height 16 of the impact element line 4 to be reduced below the conventional standard of three (3) feet, by an amount generally corresponding to the “drop” in vehicle elevation resulting from the length 15 and or the strength characteristics of the structure or material of bed 9 . For example, if the strength of the structure or material of bed 9 is increased, then the length 15 of the bed and/or the height 16 of the impact element line 4 can be increased accordingly. Likewise, as the strength of the structure or material of bed 9 is reduced, then the length 15 of bed 9 and/or the height 16 of the impact element line 4 may be reduced. According to a preferred embodiment, the height 16 of the impact element line 4 for use in combination with bed 9 and the curb 2 is within a range of approximately six (6) inches to thirty (30) inches, however, other heights of the impact element line above the finish grade elevation may be used to suit an installation for a particular application, such as within a range of approximately zero (0) inches above grade to several feet or more above grade.
[0041] According to any preferred embodiment of the present invention, the interaction of the length 15 of bed 9 , and the strength characteristics of the structure or material of bed 9 , and the height 16 of the impact element line 4 is intended to provide an adaptable barrier system configured to ensure that the chassis of any vehicle that traverses the length 15 of bed 9 will come in contact with the impact element line 4 . The barrier system of the present invention is intended to avoid the use of conventional approaches that include high walls, large impact elements and/or long expanses of crushable material. The embodiments of the present invention disclosed herein are intended to provide an adjustable and adaptable system comprising combinations of “stages” or “layers” of protective elements that provide flexibility to designers for adaptation to various applications having needs such as small installation areas, required pedestrian access, or when the barrier system is desired to be unobtrusive and to minimize the appearance of the barrier from detracting from (or drawing attention from) the surroundings.
[0042] In conventional barrier applications involving a “rigid” trafficable surface, the typical height of an impact element that is necessary to contact the chassis for most “high threat” type vehicles is approximately 18 inches. Accordingly, the Applicants believe that the height of an impact element line used in combination with a bed of a deformable structure or material according to the present invention, may be reduced by an amount corresponding to the drop in elevation experienced by the vehicle as it traverses the bed. For example, if a bed of a deformable structure or material is configured to provide a drop in elevation of the vehicle by twelve (12) inches, then the height of the impact element line may also be generally reduced by a corresponding twelve inches, in order to maintain the height of the impact element line at an effective height of 18 inches with respect to the vehicle.
[0043] Referring to FIGS. 1 and 2 , the vehicle barrier system 11 is shown according to one embodiment. The system is shown to include a trafficable surface 1 , over which all vehicles can generally pass. A first impact element shown for example as curb 2 lies along the trafficable surface 1 and is backed by a compressible zone 3 and a second impact element shown as an impact element line 4 . The impact element line 4 is shown to separate the barrier system from the protected region 5 . Beyond the protected region 5 is shown the asset 12 (e.g. building, etc.) that is intended to be protected by the barrier system. The trafficable surface 1 may form a part of the barrier system by modifying its surface through addition of frictional elements (e.g. paving, aggregates, etc.) that allow it to contribute to the attenuation of an advancing vehicle.
[0044] According to a preferred embodiment as shown in FIGS. 7 and 8 , the first region including trafficable surface 1 can be comprised of three distinct sub-regions. Trafficable surface 1 A is separated by a generally upright impact element (shown as a vertical element line 1 B) from trafficable surface 1 C. In this embodiment, vertical element line 1 B (e.g. wall, bollard line, wall segment line, median, curb, tree line, planter, line of benches, etc.) serves to reduce the speed of vehicles attempting to breach the barrier system. The vertical element line 1 B tends to reduce a vehicle's speed by “forcing” a vehicle to drive around the vertical element, causing the vehicle to reduce speed to maintain steering, or to drive through the vertical element, causing the vehicle to reduce speed through impact or vehicle damage or destruction. Additionally, trafficable surfaces 1 A and 1 C can be modified through addition of a frictional element (e.g. paving, aggregate, etc.) that is intended to improve the ability of the trafficable surfaces to contribute to the reduction in speed of an advancing vehicle.
[0045] In the embodiment shown in FIGS. 1 and 2 , trafficable surface 1 can also be modified to become a vehicle attenuating device by changing the surface composition to a material (e.g. pavers, concrete or asphalt with added aggregates such as sand or stone, etc.) that has a higher coefficient of friction than a standard roadway wearing course. The curb 2 is intended to reduce the speed of the vehicle through impact, and also cause the vehicle to “jump”. According to the embodiment, when the vehicle reaches the deformable zone 3 , it not only bears on bed 9 , but it also descends upon the surface cover layer 7 and bed 9 with a generally vertical impact force, (as shown schematically in FIG. 5 ). The first impact element in the form of the curb 2 may be formed of stone, reinforced concrete, wood, etc. As well, the curb may be capped with steel and/or pinned to a foundation below (not shown) for additional strength. According to a preferred embodiment, the curb 2 has a height that is typically in a range of approximately 3 inches to 12 inches high above the level of the trafficable surface, but may be provided with any suitable height for use with a barrier for intended vehicle types.
[0046] According to the illustrated embodiment the deformable zone 3 comprises a surface cover layer 7 , a bed 9 having a deformable structure or material for lowering the elevation of the vehicle, and a confining structure 8 . The top of surface cover layer 7 (e.g. formed from a material such as concrete, brick, pavers, tiles, cobble, planting, soil, sedum, sand, wood, plastic, etc.) is shown at approximately the same elevation as the top of the curb 2 . Surface cover layer 7 serves to spread relatively small bearing loads so that bed 9 , below, does not substantially deform, thus allowing pedestrians and the like (e.g. horses, light vehicles such as golf carts, hand trucks, etc.) to travel over this region of the vehicle barrier system without deforming the structure or material of bed 9 below. According to a preferred embodiment, the structure or material of bed 9 is designed to fail (e.g. deform, crush, collapse, compress, breakaway, yield, deflect, etc.) under loads generally equal or greater to the loads created by the tires of a vehicle having a weight of approximately 2,500 lbs. According to alternative embodiments, the bed may be configured for suitable deformation with vehicles having other loading conditions as determined in a particular application.
[0047] According to one preferred embodiment the bed 9 comprises a compressible material formed from cellular concrete having a compression strength within the range of approximately 30 pounds per square inch (psi) to 60 psi and formed with a substantially uniform density, such as may be commercially available from the Engineered Arresting Systems Corporation of Aston, Pa. According to an alternative embodiment, the compressible material may be other suitable materials (e.g. wood, plastics, metallic and/or polymeric materials, etc.) that are configured to crush or collapse under a predetermined loading condition, or may have different or other strength characteristics, or may have variable density (such as by containing voids of air ranging in sizes from small to large). For example, the material may be a metallic or polymeric material formed with a plurality of voids therein, such as a metallic foam or synthetic foam material, or any suitable combination of such materials and configured to compress or crush under predetermined loading conditions. By further way of example, the bed may comprises a structure configured to deform under predetermined loading conditions, such as a framework, lattice, honeycomb, or other deformable support structure and constructed of any suitable material such as metal, polycarbonate, plastic, composite metal, etc. According to other alternative embodiments, the material may be a generally incompressible material that is configured to deform under certain predetermined loading conditions, such as a liquid, slurry, gel, or other suitably deformable material.
[0048] The bed 9 is shown contained by a confining structure 8 . According to a preferred embodiment, the confining structure is provided in the form of a reinforced concrete foundation (e.g. trench, pit, etc.). According to other embodiments the confining structure may be formed from a metal trough, wood form-work, fabric mesh or other suitable material. The confining structure 8 is intended to retain the structure or material of bed 9 so that when the structure or material deforms, the confining structure 8 restrains the structure or material. For example, when the material comprises a cellular concrete material, the material crushes “in place,” thus the need for “empty pockets” in the confining structure and other supporting foundations (not shown), to accommodate for any displaced material can be minimized or avoided.
[0049] Referring to FIGS. 3-6 the impact element line 4 is shown as a “foundation” type impact element where the structure of the impact element extends below grade and “links” (or is otherwise coupled) to a relatively significant subsurface foundation such as, for example, the confining structure 8 , a building foundation, or the like). Such foundation type impact elements are intended to provide a relatively “heavy” ballast material below grade to minimize the volume of the impact elements above the trafficable surface, thus increasing the ease of pedestrian access and minimizing visual obstructions along the security perimeter.
[0050] According to one embodiment, the impact elements are “bollards” formed from a shell of material (e.g. steel, etc.) having a cavity containing a fill material (e.g. cement, reinforced concrete, metal, stone, wood, plastic, etc.). The shell may include internal braces (not shown), such as steel plates, to provide additional strength. The shell and fill material may be integrally formed with a foundation below grade so that loading from vehicle impact upon the impact elements can be transferred to the foundation. Use of foundation type barriers are generally desirable for installed “permanent” type barrier systems, in which the impact elements are intended to be present for an extended time period. According to one embodiment the foundation impact elements include a steel shell filled with reinforced concrete and having a minimum cross section area of approximately 144 square inches. According to an alternative embodiment, the foundation impact element line is a wall or line of wall sections having a thickness up to and including approximately 12 inches. In the embodiments where the impact elements of the impact element line 4 are bollards or walls, the height of said impact elements is intended to be smaller than the typical 30 inch height of most conventional vehicle “anti-ram” type barriers. The height of the impact element 4 may be lower than a typical “standard height” barrier because the impact elements are backing the deformable zone 3 that tends to lower the effective height of threatening vehicles. According to an alternative embodiment, the impact elements may be provided in various shapes, sizes and materials. For example, the cross sectional area may be decreased with the use of higher strength materials or the cross sectional area may be increased with the use of lower strength materials, etc. According to another alternative embodiment where the impact element line is made up of bollards, the bollards may be connect by beams (e.g. steel, concrete, reinforced concrete, wood, etc.). According to a further alternative embodiment where the impact element line is made up of bollards connected or linked by beams or low walls, these impact elements may be covered in a suitable pedestrian seating material (metal, wood, concrete, glass, etc.) and used as a bench or other suitable article.
[0051] According to a particularly preferred embodiment the trafficable surface 1 (e.g. roadway, parking lot, etc.) includes trafficable surfaces 1 A and 1 C separated by a vertical element 1 B. Vertical element 1 B is shown as a low concrete wall configured to separate traffic from surfaces 1 A and 1 C. Surfaces 1 A and 1 C may be formed from standard roadway asphalt or the like. The first impact element in the form of a curb 2 is preferably a granite curb that is “pinned” to a foundation below the trafficable surface 1 . The curb 2 preferably extends approximately six (6) inches above the grade of the trafficable surface 1 , and is six (6) inches in length. The foundation is shown continuous with the confining structure 8 that contains the structure or material of bed 9 . The confining structure 8 is preferably a reinforced concrete foundation having a depth 17 that is approximately four (4) feet deep. Contained in the concrete foundation of the confining structure 8 is a deformable material preferably made from a crushable cellular concrete material having a compressive strength within a range of approximately 30-60 psi. The bed 9 preferably has dimensions of approximately 48 inches in length, 36 inches in depth, and may have any suitable width to accommodate the intended application. Above the bed 9 having the deformable material is shown the surface cover layer 7 . Surface cover layer 7 is preferably made from stone pavers or the like and has a depth of approximately three (3) inches. As shown in FIGS. 3-6 , the top of the surface cover layer 7 is preferably at approximately the same elevation as the top of curb 2 . Beyond the bed 9 is shown the impact element line 4 . Impact element line 4 preferably comprises either a low wall formed from one or more sections extending approximately sixteen (16) inches above the top of cover layer 7 , and having a length of approximately twelve (12) inches and may have any suitable width corresponding to the width of bed 9 . Alternatively, the impact element line may formed from rows of bollards comprising steel shells containing concrete or the like and having a diameter within the range of approximately twelve (12) inches to sixteen (16) inches, and a height of approximately sixteen (16) inches above the surface layer. According to the embodiment, the bollards are configured in groups of at least two and spaced at intervals of approximately 48 inches on center.
[0052] According to another preferred embodiment the first impact element 2 is a granite curb that is “pinned” to a foundation below grade. The curb 2 extends approximately six (6) inches above the trafficable surface 1 , and is approximately six (6) inches in length. The foundation is preferably substantially continuous with the confining structure 8 that contains the structure or material of bed 9 . The confining structure 8 is preferably a reinforced concrete foundation that is approximately 48 inches deep. Contained in the concrete foundation 8 is the bed 9 having a deformable material preferably made from crushable cellular concrete or the like and having a compressive strength within the range of approximately 30-60 psi. The bed 9 preferably has dimensions of approximately 20 feet in length, 36 inches in depth, and variable width to accommodate the intended application. Shown above bed 9 is the surface cover layer 7 that is preferably a sedum planting or the like, such as typically used in green roof installations, etc. and having a depth of approximately two (2) inches. As shown in FIGS. 3-6 , the top of the surface cover layer 7 is configured at approximately the same elevation as the top of curb 2 . Behind the bed 9 and cover layer 7 is the impact element line 4 that preferably includes a low wall extending approximately sixteen (16) inches above the top of the cover layer, and having a length of approximately twelve (12) inches and a width corresponding to the width of at least one of the bed, the cover layer 7 , and the foundation 8 . According to alternative embodiments, the dimensions of the curb, and the bed, and the confining structure and the impact element line may be varied to suit a particular application.
[0053] The impact element line 4 of the vehicle barrier system 11 may also be provided as “inertia” or “friction” type barriers that are intended to rely on their weight and friction with the surface on which they are placed to provide a desired degree of impact resistance. Such inertia type impact elements may be “preformed” concrete structures (such as commonly known as “jersey barriers”) or concrete “planters” or the like that are intended for placement at a desired location. The inertia type impact elements are advantageous for “temporary” type barrier systems, in which the impact elements may only be required for a relatively short time period, or where subgrade conditions prevent easily constructing a foundation, as in the case of shallow depth utility lines, etc.
[0054] According to another embodiment of the vehicle barrier system as shown in FIGS. 9 , 10 and 16 , a sidewalk 120 is disposed between the curb 102 and a bed system 103 . The bed system 103 comprises a composite, multi-layer arrangement of materials or structure intended to arrest the progress of a vehicle, yet permit unimpeded pedestrian traffic in a pedestrian area. For example, the bed system 103 is shown to comprise a first layer, shown as a deformable material layer 109 and a second layer, shown as a pedestrian cover surface material layer or structure 107 , substantially overlying a deformable material layer or structure 109 . The sidewalk 120 is intended for pedestrian traffic, but may support incidental vehicular traffic. Typical construction for the sidewalk 120 involved a decorative paving layer (e.g. cobble, stone, brushed concrete, soil, gravel, asphalt, etc.) over compacted earth with or without a concrete sub-base in between. The sidewalk 120 serves to provide a buffer zone between the trafficable surface 101 and the bed system 103 , so that incidental vehicular traffic adjacent to the trafficable surface 101 does not disturb the deformable structure or material layer 109 of the bed system 103 . The sidewalk 120 may be constructed to building code standards for sidewalks or terraces subject to vehicular traffic, as indicated in building codes such as the New York City Building Code or the International Building Code, where such a sidewalk would typically be required to have a Minimum Uniform Live Load capacity of 250 pounds per square foot (psf) or Minimum Concentrated Live Load requirement of 8,000 lbs. In this embodiment the curb 102 may be used, as in previous embodiments, to direct a potential threat vehicle upwards so that it descends into the bed 103 . According to a preferred embodiment, the curb has a height that extends within a range of substantially one (1) inch to ten (10) inches above the trafficable surface. Under other scenarios, the curb may not serve to direct the vehicle upwards, for example, in the case where a vehicle's speed might not be high enough or its suspension calibrated so that the vehicle's wheels do not lose contact with the trafficable surface 101 , curb 102 , or sidewalk 120 . In this scenario, the curb would serve as a visual indicator to vehicle drivers, signaling the end of the trafficable zone and the beginning of the pedestrian sidewalk 120 .
[0055] In related embodiments, as shown in FIGS. 11 , 12 , 13 , 14 , and 15 the curb 102 is replaced with a visual indicator element 121 . The visual indicator element 121 provides a recognizable cue to the driver of a vehicle of the delineation of the trafficable surface 101 and the pedestrian sidewalk 120 . The visual indicator element 121 is shown as generally flush (e.g. having a substantially equivalent top elevation) with both the trafficable surface 101 and the pedestrian sidewalk 120 . The visual indicator element 121 alerts drivers through a difference in appearance such as painting or markings (e.g. in pattern(s), distinctive color scheme, etc.) or having a distinct material and/or texture (e.g. stone, concrete, wood, metal, etc.) from the surrounding paving conditions of the trafficable surface 101 and the sidewalk 120 .
[0056] In a preferred embodiment the confining structure 108 of the bed system includes retaining walls 122 (e.g. formed from reinforced concrete, stone, sheet metal, wood, compacted soil, masonry, etc. or any suitable combination). These walls 122 serve to separate the deformable material layer 109 from the surrounding sub-grade condition (e.g. soil, sand, concrete, utility lines, etc.). In related embodiments, the walls are defined as having four (4) or more distinct sides (i.e. front 122 A, left 122 B, right 122 C, and rear 122 D). Accordingly, the rear wall 122 D is intended to bear the impact of a vehicle that has traversed the bed system 103 , broken through the pedestrian cover surface layer 107 , and deformed the deformable material layer or structure 109 (such as described in previous embodiments as being performed by the impact element line 4 ). The rear wall 122 D is designed to stop (e.g. arrest, halt, disable, etc.) a vehicle that impacts it (as described in previous embodiments). In some embodiments, such as those indicated in FIGS. 10 , 11 , 12 and 15 , the top of the rear wall is shown at an elevation substantially equivalent with the top of the pedestrian cover surface layer 107 . In other embodiments, such as shown in FIG. 13 , the height of the top elevation of the rear wall 122 D is above the top elevation of the pedestrian cover surface layer 107 (such as, but not limited to, a height within the range of approximately 0-24 inches above the pedestrian cover surface). In this embodiment, the rear wall 122 D can be equipped with an architectural cover (e.g. bench, wall, curb, etc.) of unique material (stone, metal, glass, wood, composite, polymer, etc.) in order to enhance its aesthetic appearance. In other embodiments, such as FIG. 14 , the top elevation of the rear wall 122 D is below the top elevation of the pedestrian cover surface layer 107 . The relative elevation of the rear wall 122 D is determined by the expected elevation of a potential attacking vehicle after it has been lowered in elevation by compressing into the deformable material layer 109 .
[0057] According to a related embodiment as shown for example in FIGS. 12 and 15 , a second visual indicator element 123 is disposed between the sidewalk 120 and the bed 103 . The second visual indicator element 123 is intended to provide a second cue to a vehicle that has already crossed over the first indicator element and is driving on the sidewalk 120 . The second visual indicator element 123 may be similar to the first visual indicator element 121 in that it is distinct in appearance from the sidewalk 120 , the trafficable surface 101 , and the pedestrian cover surface layer 107 (as shown to substantially overlie the deformable material layer 109 ).
[0058] According to a further embodiment as shown for example in FIG. 16 , both the first indicator element 121 and the second indicator element 123 are replaced by curbs 102 and 124 respectively, curb 102 shown for example as having an equivalent top elevation with the pedestrian sidewalk, and curb 124 shown for example as having an equivalent top elevation with the top of the pedestrian cover surface 107 of the bed 103 . This “double curb” system serves to provide visual as well as an elevation change (e.g. tactile indication) to alert a driver that the vehicle has left the trafficable surface and is approaching a restricted area, and imparts a vertical velocity component on the vehicle as it enters the bed system 103 .
[0059] According to a further embodiment, the pedestrian cover surface layer 107 is intended to spread pedestrian loads over the deformable material layer 109 in the bed system 103 . The pedestrian cover surface layer 107 comprises a sidewalk paving material (e.g. paving elements such as masonry, bricks, stone, cobbles, pavers, etc.—which may be provided in the form of a “loose” unit paving system where the paving elements are laid loose and adjacent to one another over the deformable material) or a planting system (e.g. a material such as soil, sand, grass, sedum, bushes or other planting material, etc.) configured to support pedestrian loads, but configured to give way under vehicle loads and/or the tire motion (spinning, turning, etc.) of a vehicle that drives over the pedestrian cover layer 107 so that the tires of the vehicle breach (e.g. crush, tear, break, etc.) the pedestrian cover layer 107 and come in contact with the layer of deformable or compressible material 109 below. Once the pedestrian cover surface layer 107 is breached, the spinning motion of the vehicle's tires combined with the weight of the vehicle cause it to deform the deformable material layer 109 so that the deformable material layer 109 fails inelastically (i.e. breaks, tears, or is crushed, etc.). According to a preferred embodiment, the deformable material layer 109 comprises a structure (e.g. lattice, honeycomb, etc.) constructed of metal, polycarbonate, plastic, composite metal, wood, etc. and configured to breakaway, collapse, crush, sink or otherwise deform under the weight of the vehicle. The deformable material layer 109 may also comprise a substance (e.g. uniform or composite), alone or in combination with a structure, having characteristics that permit the material to crush, compress, yield, displace, or otherwise deform, such as, for example, cellular concrete, resin, metallic foam, synthetic foam, polymeric foam, (or other material having voids filled with air or the like) or any other suitable material of combination of such materials, having a predefined compression strength, sufficient to crush under a tire(s) of a vehicle weighing at least approximately 2,500 pounds (lbs). The vehicle's weight combined with the rotation (e.g. “spinning” etc.) of the vehicle's tires is intended to deform (e.g. collapse, crush, compress, yield, displace, etc.) the deformable material layer 109 , so that the elevation of the vehicle “drops” or is otherwise “lowered.” The deformation of the deformable material layer 109 of the bed system 103 tends to lower the effective height of the vehicle, as the elevation of the vehicle decreases (e.g. sinks, falls, etc.) into the deformable material 109 , as well as reducing the vehicle's speed, due at least in part to the friction between the tires and the compressible structure of material.
[0060] According to any exemplary embodiment of the present invention, the vehicle barrier system is intended to provide an installed barrier for use along a boundary or border such as a security perimeter to protect sites that may be susceptible to a vehicle born intrusion or attack. The vehicle barrier system is designed so that in can be crossed by pedestrians and the like, but prevents passage by vehicles such as automobiles. The vehicle barrier systems employs a variable “composite” approach, using a combination of different attenuation devices and methods in succession to stop a vehicle within a short distance or limited space, such as are typically encountered near buildings and the like. The vehicle barrier system is intended to provide an installed barrier having a “rating” as a crash type barrier consistent with applicable governmental rating criteria. For example, the vehicle barrier system is intended to provide a rating of at least any one of the following K ratings (i.e. a measure of the barrier's potential to stop a vehicle at escalating speed as dictated by standards determined by the U.S. Department of State: K4 (15,000 lb vehicle traveling at 30 miles per hour (mph)), K8 (15,000 lb. vehicle traveling at 40 mph), or K12 (15,000 lb. vehicle traveling at 50 mph.
[0061] It is also important to note that the construction and arrangement of the elements of the vehicle barrier system as shown in the preferred and other exemplary embodiments is illustrative only. Although only a few embodiments of the present inventions have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sequence, sizes, dimensions, structures, shapes, profiles and proportions of the various elements, values of parameters, mounting arrangements, use of materials, ballast, orientations, compositions of compressible materials, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements show as multiple parts may be integrally formed. By further way of example, the deformable zone may include a bed having any suitable structure or material configured to support the weight of pedestrians and other generally permissible loads, but is configured to deform sufficiently under the weight of a vehicle or other generally impermissible loads so that the elevation of the vehicle is lowered in relation to the surface grade and to facilitate contact of the vehicle chassis with a second impact element that may have a generally lowered elevation. It should also be noted that the system may be used in association with a wide variety of applications (e.g. corporations, government facilities, entertainment venues, private residences, hospitals, hotels, religious and cultural institutions, etc.) and that the elements of the system may be provided in any suitable size, shape, material and appearance that meets applicable design and performance standards and that creates a desired appearance corresponding to the location of the system. Accordingly, all such modifications are intended to be included within the scope of the present inventions. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the preferred and other exemplary embodiments without departing from the spirit of the present inventions.
[0062] The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. Other substitutions, modifications, changes and omissions may be made in the design, operating configuration and arrangement of the preferred and other exemplary embodiments without departing from the spirit of the inventions as expressed in the appended claims.
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A security barrier system for use with a trafficable surface and a site requiring protection from advancing vehicles includes a composite bed system having a plurality of elevations and comprising a first layer beneath a second layer. The first layer includes a deformable material configured to collapse when subjected to vehicle loads, and the second layer includes a pedestrian cover surface over the deformable material that conceals the deformable material. The pedestrian cover surface is configured to support pedestrian traffic over the deformable material without permanently collapsing the deformable material and to collapse along with the first layer when subjected to vehicle loads. A structure beyond the bed system is provided to resist the impact of a vehicle that has traversed the bed system.
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BACKGROUND
[0001] The present invention relates to the brazing of copper armature conductors to a commutator during the production of automotive starting motors.
[0002] Automotive starting motors are typically DC machines including a field winding on the stator, an armature winding on the rotor and a mechanical rectifier known as a commutator. The stator comprises a laminated ferromagnetic material equipped with protrusions around which the coils of the field winding are wrapped. The rotor includes a laminated core which is slotted to accommodate the armature winding. The armature winding is comprised of a plurality of copper armature conductors wound on the slots of the rotor. The commutator is a mechanical rectifier comprised of a plurality of parallel copper segments insulated from one another and arranged in cylindrical fashion. Carbon brushes ride on the commutator and serve to conduct direct current to the armature winding.
[0003] In production of an automotive starting motor, the copper armature conductors must be joined to the copper segments of the commutator to provide a connection between the armature winding and the commutator. In one known process, the copper armature conductors are typically joined to the commutator using a process of welding commonly referred to as “hot staking.” Hot staking involves applying a current through the armature conductors and a corresponding slot in the commutator, which generates heat. This is done by a pair of electrodes, one of which is positioned above and applies downward pressure onto the two armature conductors that are to be welded together and welded to a corresponding slot in the commutator. The combination of the heat and force softens the copper armature conductors and causes them to deform. After a period of time, current to the electrode is terminated and the electrode is removed. Thereafter, the copper conductors re-harden and form a bond with the walls of the slot in the commutator. The armature is then rotated to allow the hot staking machine to weld the next set of conductors in the respective slot of the commutator.
[0004] Unfortunately, in a hot staking operation, it is difficult to keep the tungsten electrode at a constant temperature. Instead, the electrode typically becomes hotter with each successive weld due to the same current being provided through the electrode during each weld and not much time being provided for cooling between welds. After several welds, the very hot electrode can cause damage by penetrating too far into the slot of the commutator when it contacts a conductor and causing the conductor to completely deform and melt into a U-shape around the electrode. These welds are faulty and are not capable of conducting current within an operating armature.
[0005] Brazing is another technique that can be used to electrically connect the conductor pairs of the armature and the corresponding slots in the commutator. In a brazing operation, a filler material is positioned in the location where the conductors are to be joined and heat is generated by a current provided by electrodes as in a hot staking application. As the temperature increases, the filler material begins to melt, which typically happens at a temperature at least 500° F. lower than the temperature at which the copper conductors begin to deform. As the filler material melts, it flows between the two conductors desired to be joined by capillary action.
[0006] In a typical brazing operation for conductors of an armature and commutator, a thin, flat brazing ribbon is placed between the faying surfaces of the conductors and the electrode then applies pressure and a current. After the brazing material melts, the remaining ribbon is withdrawn by hand. This process can be completed separately for the connection between the two conductors of the armature and then for the connection between the bottom armature conductor and the commutator slot. The armature can then be rotated and the brazing process repeated on the next set of conductors.
[0007] In contrast to hot staking, brazing advantageously avoids the problem of excessive heat causing the conductors to deform. That is, since the conductors that are joined are not melted in the brazing process, they retain their original shape, and edges and contours are not eroded or changed by the formation of a fillet. Further, since less heat is required to heat the brazing material to its melting temperature, the brazing process is more efficient than hot staking.
[0008] In a brazing operation, the brazing material must be carefully positioned and held in place at the conductors until the commutator is joined to the armature and the brazing process is completed. Inserting the brazing ribbon is typically done manually, which is inefficient and also requires two separate brazing steps, as discussed above. Further, it requires the fingers of the operator to be placed undesirably close to the electrodes, which press down onto the conductors with a rather large force of around 500 pounds. Brazing clips can be fitted on the armature conductors. Undesirably, however, it has been found that such clips can move from their proper position on the armature conductors when the commutator is joined to the armature.
SUMMARY OF THE INVENTION
[0009] The present invention provides an apparatus for and a method of brazing copper armature conductors to a commutator during the production of automotive starting motors. In the inventive method, two conductors of the armature are brazed together and are also brazed to the corresponding slot in a commutator in a single step. The process is aided by an inventive brazing clip which includes a cleat or inwardly bent tab that engages the conductor of an armature to hold it in place.
[0010] In one form thereof, the present invention provides a method of brazing a pair of armature conductors and a commutator conductor. In this inventive method, an armature having a conductor pair comprising two spaced conductors is provided and a commutator having a commutator conductor is also provided. A brazing material is formed into a brazing clip configured to fit onto one conductor of the conductor pair of the armature, typically the lower conductor that is adjacent the commutator slot. A cleat is formed in the brazing clip and the clip is slid over the one conductor. The commutator is joined to the armature so that the commutator conductor is aligned with the conductor pair of the armature while the cleat prevents longitudinal movement of the brazing clip relative to the one conductor. A current is applied to the armature and thereby brazes together the pair of armature conductors and the commutator conductor.
[0011] Advantageously, the inventive method allows the brazing clips to be installed onto the armature conductors all at once, yet the clips need not be repositioned after the commutator is installed. This allows the process to be automated and avoids the need for an operator to place his or her hands near the conductors when the electrode is being applied.
[0012] In exemplary embodiments, the cleat is pointed and sharp. This allows the cleat to pierce the surface of the conductor and thereby “dig in” to the copper conductor and prevent longitudinal movement along the conductor of the armature. Similarly, the cleat or inwardly bent tab may also be positioned in an indentation previously formed in the conductor to thereby resist longitudinal movement of the brazing clip on the conductor by engagement of the cleat with the sidewalls of the indentation. The cleat or inwardly bent tab may also biasingly engage the conductor to thereby increase the bearing pressure exerted between the brazing clip and the conductor on the side of the conductor opposite the cleat to thereby resist longitudinal movement of the brazing clip on the conductor by frictional forces.
[0013] In accordance with these teachings, the brazing material is formed into a clip whose shape substantially conforms to the outer periphery of the armature conductor. The cleat or tab can be formed as a bent corner of the brazing clip. The number of cleats to be provided is a design variable. Since there are typically four corners on the material that is used to form the clip, there can be four cleats formed from the corners. Other variations are possible within the scope of these teachings.
[0014] In another form thereof, an exemplary apparatus for connecting an armature conductor pair and a conductive slot of a commutator is provided. The apparatus comprises a brazing clip shaped to conform to and fit over a conductor of an armature. The brazing clip has two edges that are spaced apart to define an open channel extending along the lengthwise direction of the clip. At least one of the edges terminates in a bent corner section, the bent corner section comprising a cleat configured to engage the conductor of the armature and prevent movement of the clip along a longitudinal axis of the armature conductor.
[0015] In certain embodiments, the armature conductor on which the brazing clip is placed has a cross-sectional profile that corresponds to the shape of the brazing clip. Optionally, the armature conductor may include an indentation which the cleat engages, which holds the brazing clip in place relative to the armature conductor. In other embodiments, the brazing clip can include two or more cleats.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The above-mentioned aspects of the present invention and the manner of obtaining them will become more apparent and the invention itself will be better understood by reference to the following description of the embodiments of the invention, taken in conjunction with the accompanying drawings, wherein:
[0017] FIG. 1 is an exploded perspective view showing an armature with a commutator and inventive brazing clips;
[0018] FIG. 2 is a perspective view of the components shown in FIG. 1 assembled together but before a brazing operation;
[0019] FIG. 2A is an enlarged perspective view of the section shown in FIG. 2 before a brazing operation;
[0020] FIG. 2B is an enlarged perspective view of the section shown in FIG. 2 after a brazing operation;
[0021] FIGS. 3A-3C are fragmentary perspective views showing an inventive clip of the present invention being installed on an armature conductor and an armature thereafter being mated with a commutator;
[0022] FIGS. 4A-4C show various embodiments of the inventive brazing clip before it is formed into it final shape for installation;
[0023] FIGS. 5A-5D show various geometries of the inventive brazing clip; and
[0024] FIGS. 6A-6C depicts a process for making brazing clips in accordance with the present invention.
[0025] Corresponding reference numerals are used to indicate corresponding parts throughout the several views.
DETAILED DESCRIPTION
[0026] The embodiments of the present invention described below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may appreciate and understand the principles and practices of the present invention.
[0027] Turning now to FIG. 1 , one embodiment of a device 20 is shown having an armature 22 to which a commutator 24 may connect by means of cylindrical shaft 26 that frictionally fits into cylindrical bore 28 . Armature 22 includes a series of first conductors 30 extending outwardly from the armature body and these conductors 30 collectively form an outer circular periphery of conductors 30 . A second series of conductors 32 also extend outwardly from the armature body and collectively form an inner circular periphery of conductors 32 .
[0028] Commutator 24 has a series of parallel conductive segments 34 typically formed from copper which extend in the longitudinal direction of the commutator 24 and terminate in a series of risers 36 which define slots 38 , which are also typically formed of copper. Advantageously, the height of the risers 36 can be less than is needed for a hot staking process. The windings of the armature comprise a plurality of conductor pairs each having a conductor 30 and a conductor 32 , and each conductor pair 30 , 32 is electrically connected to a corresponding slot 38 of the commutator 24 . The conductors 30 and 32 are also typically formed of copper.
[0029] In embodiments in accordance with these teachings, the electrical connection between the conductors 30 and 32 of the armature conductor pairs and the corresponding slot 38 in the commutator 24 is made via brazing. A brazing material is provided in the form of a brazing clip 40 , two of which are shown in FIG. 1 and the inventive details of which are described in more detail below.
[0030] FIGS. 2 and 2A depict the device 20 with the commutator 24 assembled to the armature 24 . As shown in more detail in FIGS. 2A and 6A , clip 40 is made of a thin brazing material, typically formed from an alloy of copper, phosphorus and silver. There are a large number of commercially available brazing alloys that may be suitable for use with the present invention, and one suitable alloy is known by those skilled in the art as BCuP 5, which has a composition of about 15% silver, 5% phosphorous, 80% copper and trace amounts of other materials.
[0031] Clip 40 has two edges that define an open channel or slot 42 extending along its lengthwise direction. In the embodiment shown in FIGS. 2A and 6 , one of the edges of the clip terminates in a bent corner section, or “cleat” 44 which is also referred to herein as an inwardly bent tab. The inventive cleat 44 prevents the clip from moving on the conductor 32 when the commutator is assembled to the armature, as explained below.
[0032] FIGS. 2 and 2A show the armature, conductors 30 , 32 , slot 38 and clip 40 before the brazing operation is completed. To conduct the brazing operation, a copper electrode 46 (only a working portion of which is shown) is positioned over a conductor 30 in a location over one of the slots 38 and the electrode 46 is moved downward into contact with the conductor 30 , applying force to the conductors. Electrode 48 (only a working portion of which is shown) is brought into contact with segment 34 of commutator 24 to complete the electrical circuit. The brazing material is typically positioned in the electrical circuit at two locations, between conductors 30 and 32 and between conductor 32 and commutator slot 38 . In the illustrated embodiments, a single brazing clip 40 substantially surrounds conductor 32 and provides the brazing material for both of these two locations in the electrical circuit.
[0033] As force is applied to the conductors from the electrode 46 , a voltage is applied across the electrodes 46 and 48 , causing a current to flow through the conductors 30 , 32 , clip 40 and slot 38 . The brazing current can be typically around 10,000 amps, which is applied for about 1 second or less, which typically produces sufficient heat to melt the brazing material. The electric current causes the copper conductors and clip to heat up. The clip 40 has a melting temperature of about 1420° F., whereas the copper conductors and slots have a higher melting temperature of about 2000° F., such that only the brazing material liquefies during the brazing operation. As the brazing material liquefies, the phosphorous component cleans the copper and the brazing alloy flows by capillary action into the spaces between the conductors 30 and 32 and between conductor 32 and slot 38 .
[0034] After a period of time, the current is terminated. The downward force applied by the electrode, which can be about 500 lbs., is maintained for a time after the current is terminated. Thereafter, the electrodes are removed and the brazing material hardens and forms a bond with conductors 30 and 32 and with the slot 38 . As shown in FIG. 2B , the brazing operation results in clip 40 forming two secure joints 50 and 52 which electrically connect conductors 30 and 32 and slot 38 . After the brazing of one pair of conductors 30 , 32 and a slot 38 is completed, the armature is rotated to allow the same brazing operation just described to take place on the next pair of conductors and associated slot of the commutator. This process is continued until all of the conductors are brazed.
[0035] The role of the inventive brazing clip in the operation just described can be better understood with reference to FIG. 3 , which shows a portion of a conductor 32 with a brazing clip 40 installed in the desired position for brazing. While many manufacturing steps can be conducted in various orders, in one embodiment of the assembly protocol of device 20 , the clips 40 are placed onto all of the conductors 32 in the desired locations, after which the commutator is placed onto shaft 26 ( FIG. 1 ) and moved into the proper position with respect to armature 22 .
[0036] With reference to FIG. 3A , clip 40 is moved along the longitudinal axis of conductor 32 , i.e., in the direction of arrow 56 . As this is done, the cleat 44 frictionally engages the conductor 32 . Turning to FIG. 3B , the clip 40 is shown in its final position, at which the cleat 44 engages an optional rectangular indentation 54 formed in conductor 32 . The optional indentation 54 provides an additional means that complements the cleat 44 and assists securing the clip 44 in its final position. That is, the sidewalls of the rectangular indentation 54 tend to block the pointed cleat 44 and thereby prevent the clip 40 from sliding in a longitudinal direction along the conductor 32 .
[0037] Preventing the longitudinal movement of clip 40 , i.e., movement in the direction of arrow 56 , is critically important during the installation of the commutator 24 to the armature 22 . As depicted in FIGS. 3B and 3C , commutator 24 moves along the direction of arrow 58 until it reaches the position depicted in FIG. 3C . In prior art assembly processes, before the commutator is moved to its final position, the slots 38 or portions of the risers 36 often contact the clips 40 and undesirably move the latter out of their proper position for brazing. When this happens, a process that could otherwise be mostly automated requires manual intervention during which an operator must reposition the clips by hand in their proper position for brazing. This manual step slows the overall assembly process, adds unpredictability and inconsistency, and thus drives up the cost of assembly.
[0038] By contrast, embodiments incorporating brazing clips 40 with the inventive cleats 44 greatly reduce and can eliminate the problem of the brazing clip moving from their installation position during assembly of the commutator to the armature or at other times during the assembly process of the motor. In some embodiments, this is achieved with pointed cleats 44 , so-named due to their functional resemblance to a cleat on an athletic shoe. The cleats “dig in” to the relatively soft copper and provide an engagement therewith that largely prevents movement of the brazing clip when minor contact, e.g., from the commutator, is made during the assembly process. In other embodiments, the cleats or inwardly bent tabs 44 may have a blunt distal end. Such blunted cleats could be positioned in indentations 54 to resist longitudinal movement. Alternatively, such blunted cleats could biasingly engage the conductor to increase the bearing pressure between the conductor and those portions of the brazing clip in contact with the conductor to thereby frictionally resist longitudinal movement of the brazing clip on the conductor. These different means for resisting longitudinal movement of the brazing clip may be employed singlely or be combined in any number of different combinations. For example, a pointed cleat could pierce the surface of the conductor, be located within a preformed indentation in the conductor and exert a biasing force against the conductor.
[0039] Configurations of the inventive clip other than the embodiment illustrated above are possible. For example, as already noted, in certain embodiments it may be desirable to form a depression on the conductors, such as depression 54 , to assist the clip in remaining in its installation position. In other embodiments, a clip having a single cleat 44 in the form of a bent corner may be sufficient. FIGS. 4A-4C shows three embodiments of clips 40 before they are formed into the shape to fit over the conductors. In FIG. 4A , a clip 40 is shown having a single cleat 40 . FIG. 4B illustrates an option in which two cleats are provided, one on the front longitudinal end of the clip and the other in the back. FIG. 4C shows a clip having two cleats, front and back and opposite sides. One of skill in the art would recognize other configurations within the scope of these teachings.
[0040] Advantageously, the inventive clips with cleats provided by these teachings are not limited to use with any specifically shaped brazing clip. Rather, the clips can be formed in any of a wide variety of shapes and still be formed with the inventive cleats. For example, FIG. 5A shows a clip 44 a having a polygonal shape; FIG. 5B show a clip 44 b having an oval shape; FIG. 5C shows a clip having a rectangular shape; and FIG. 5D shows a square shaped clip. One of skill in the art would recognize other clip geometries that could employ the inventive cleats, depending upon the cross-sectional shape of the conductors on which they are to be installed as well as other parameters.
[0041] Further, any of the wide variety of clip geometries contemplated by these teachings can be formed in a straightforward manner, as illustrated in FIGS. 6A-6C . Generally, a long “ribbon” 60 of brazing material is provided (e.g., in the form of a roll weighing 2 lbs.) and can be cut along dashed lines 62 to form flat pieces cut to the length needed to form clips 40 . After the cutting process, the cleat 44 may be formed as shown in FIG. 6B and the material is then shaped into the final form of the clip 40 shown in FIG. 6C .
[0042] One of skill in the art would readily recognize a variety of methods for cutting the ribbon and shaping it into the final clip product. For example, the initial cutting along dashed lines 62 can be performed by a small tin snips instrument, or they can be punch cut in an automated or semi-automated fashion. The forming of the cleat can be done by a small needle-nose pliers or similar instrument, as can be the shaping into the final form of the clip. The ribbon material can also be placed over a form having the desired shape of the clip to shape the clip into its final form. Numerous other tools and methods for forming the inventive clips are possible within the scope of these teachings.
[0043] While exemplary embodiments incorporating the principles of the present invention have been disclosed hereinabove, the present invention is not limited to the disclosed embodiments. Instead, this application is intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.
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An apparatus for and a method of brazing copper armature conductors to a commutator during the production of automotive starting motors. In the inventive method, two conductors of the armature are brazed together and are also brazed to the corresponding slot in a commutator in a single step. The process is aided by an inventive brazing clip which includes a cleat or inwardly bent tab that engages the conductor of an armature to hold it in place.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 11/678,067 filed Feb. 23, 2007, which is hereby incorporated by reference it its entirety.
BACKGROUND
[0002] The present invention relates to locking apparatus for downhole tools, and more particularly, to a pressure activated locking slot assembly.
[0003] Typically, when tools are run into the well bore, a mandrel is held in the run-in-hole position by interaction of a lug with a J-slot. To move the tool out of the run-in-hole position generally involves the application of torque and longitudinal force. Such an arrangement can be problematic in offshore or highly deviated sections of a well bore, where dragging forces on the tool string may create difficulty in estimating the proper torque to apply at the surface to obtain the desirable torque at the J-slot. A continuous J-slot wraps all the way around the mandrel and typically has two lugs, so that the direction of torque applied need not be reversed in order to actuate. Rather, the tool may simply be picked up and put back down to cycle.
[0004] A problem may arise when running such a tool into an offshore or highly deviated well bore. Dragging of the tool string on the well bore may cause the mandrel move relatively upwardly and rotate with respect to the drag block assembly sufficiently to result in premature actuation of the J-slot assembly. If such premature actuation occurs, subsequent downward load on the tool string may rupture the tool elements, or the tool elements may be damaged by dragging along the well bore. In addition, premature actuation may result in the tool string jamming in the well bore.
SUMMARY
[0005] The present invention relates to locking apparatus for downhole tools, and more particularly, to a pressure activated locking slot assembly.
[0006] In one embodiment of the present invention a locking slot assembly comprises: a slot; a lug configured to move within the slot; and a lock configured to prevent the lug from moving within the slot until a triggering event occurs; wherein the lock is further configured to allow the lug to move within the slot after the triggering event has occurred, so long as a predetermined condition is maintained. The triggering event may be the application of a predetermined pressure, and the predetermined condition may be a minimum pressure.
[0007] In another embodiment of the present invention a downhole tool assembly comprises: a sleeve having a slot; a lug rotator ring configured to move axially relative to the sleeve, the rotator ring having a lug configured to move within the slot; and a lock configured to prevent the lug from moving within the slot until a predetermined pressure is applied; and wherein the lock is further configured to allow the lug to move within the slot after the predetermined pressure has been applied, so long as a minimum pressure is maintained.
[0008] In yet another embodiment of the present invention a method of activating a downhole tool assembly comprises: providing a downhole tool assembly in a well bore; applying a predetermined pressure to the downhole tool assembly; and moving the downhole tool assembly upward; wherein the downhole tool assembly comprises a sleeve having a slot, a lug rotator ring configured to move axially relative to the sleeve, the rotator ring having a lug configured to move within the slot, and a lock configured to prevent the lug from moving within the slot until a predetermined pressure is applied.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] FIG. 1A is a side cross-sectional view showing one embodiment according to the present invention.
[0010] FIG. 1B is a side cross-sectional view of the embodiment illustrated in FIG. 1A , showing an unlocked position.
[0011] FIG. 2A is a side cross-sectional view showing another embodiment according to the present invention.
[0012] FIG. 2B is a side cross-sectional view of the embodiment illustrated in FIG. 2A , showing an unlocked position.
[0013] FIG. 3A is a side view showing one embodiment according to the present invention.
[0014] FIG. 3B is a side view of the embodiment illustrated in FIG. 3A , showing an unlocked position.
DETAILED DESCRIPTION
[0015] Referring now to the drawings and more particularly to FIGS. 1A and 1B , the locking slot assembly of the present invention is shown and generally designated by the numeral 10 . Locking slot assembly 10 is disposed adjacent to a lower end of a tool 12 (shown in FIG. 2A ), which is of a kind known in the art, such as a valve, a packer, or any tool requiring different positions. Tool 12 may connect to a tool string (not shown) and the entire tool string may be positioned in a well bore. The well bore may be defined by a casing (not shown) and may be vertical, or the well bore may be deviated to any degree.
[0016] Locking slot assembly 10 is illustrated below the tool 12 . Tool 12 may include, or be attached to, an inner, actuating mandrel 14 , which may be connected to the tool string. Locking slot assembly may include the actuating mandrel 14 , attached at a lower end to bottom adapter 16 . Actuating mandrel 14 and at least a portion of bottom adapter 16 may be situated within a fluid chamber case 18 and/or a lock 20 . The fluid chamber case 18 and the lock 20 may be removably attached, fixedly attached, or even integrally formed with one another. Alternatively fluid chamber case 18 and lock 20 may be separate.
[0017] At least one fluid chamber 22 may be situated between actuating mandrel 14 and lock 20 . Fluid chamber 22 may be sealed via one or more seals 24 , along with a rupture disk 26 situated in the lock 20 . Air at atmospheric pressure may initially fill the fluid chamber 22 . As the tool 12 is lowered into the well bore, hydrostatic pressure outside the tool 12 increases. Once the hydrostatic pressure reaches a predetermined value, the rupture disk 26 may rupture. After the rupture disk 26 has ruptured, the fluid outside the tool 12 will enter the tool 12 through a port 28 formed therein. The resulting increased pressure within the fluid chamber 22 will cause the fluid chamber 22 to expand (as shown in FIG. 1B ). This expansion causes the longitudinal movement of the lock 20 with respect to the actuating mandrel 14 , thus “unlocking” the locking slot assembly 10 . FIGS. 3A and 3B , which will be discussed below, further show the locked position and unlocked position respectively.
[0018] Referring now to FIGS. 2A and 2B , shown therein is an alternate embodiment of the locking slot assembly 10 . This embodiment has no rupture disk 26 . Instead, one or more shear pins 30 to prevent the lock 20 from moving until adequate pressure is present. A spring 32 may be included to keep the locking slot assembly 10 in an unlocked position. While the spring 32 shown is a coil spring, the spring 32 may be any biasing member. Likewise, the shear pin 30 may be a screw, spring, or any other shearable member. Other than the use of a rupture disk 26 and/or a spring 32 , the embodiment of FIGS. 2A and 2B functions similarly to the embodiment of FIGS. 1A and 1B . An increase in pressure causes the lock 20 to move longitudinally with respect to the actuating mandrel 14 , resulting in the unlocking of the locking slot assembly 10 (as shown in FIG. 2B ).
[0019] Referring now to FIGS. 3A and 3B , one or more lugs 34 may extend from a lug rotator ring 36 into a continuous slot 38 in a sleeve 40 , thus providing locking assembly 10 . As previously discussed, pressure may cause the lock 20 to become unlocked. In the locked position, a locking portion 42 of the lock 20 occupies space within the slot 38 , keeping the lugs 34 in a run-in-hole position, and preventing the lugs 34 from moving relative to the slot 38 . As the lock 20 moves downwardly because of increased pressure, the locking portion 42 moves out of the slot 38 , allowing the lugs 34 to move relative to the slot 38 if there is an upward or downward force acting on the sleeve 40 .
[0020] In the run-in-hole, locked position, the lock 20 is in an upward position, in which lugs 34 are engaged with locking portion 42 of the lock 20 . As the tool string is lowered into well bore, the locking slot assembly 10 will remain in the locked position shown in FIGS. 1A , 2 A, and 3 A, with the lock 20 preventing relative longitudinal movement of the lug rotator ring 36 with respect to the sleeve 40 .
[0021] Once pressure is applied and the locking slot assembly 10 is unlocked (as shown in FIGS. 1B , 2 B, and 3 B), the locking slot assembly 10 may be actuated, allowing the lug rotator ring 36 to move longitudinally with respect to the sleeve 40 . In other words, the tool 12 may be set by pushing downward on the tool string, which lowers lug 34 . While any type of slot 38 may be used, the embodiment shown uses a j-slot, and in particular, shows a continuous J-slot. Depending on the specific application and the type of slot, setting the tool may involve pushing downward on the tool string multiple times. Thus, when a continuous j-slot is used, the tool 12 may be set by up and down motion alone. This may prevent the operator from cycling through the slot and setting the tool 12 prematurely.
[0022] For retrieval, the tool string is simply pulled upwardly out of the well bore. This will cause the lug 34 to re-engage the slot 38 . Additionally, as the pressure outside the tool 12 , and thus, the pressure within the fluid chamber 22 is reduced, the lock 20 may move back into the locked position, preventing any subsequent relative movement of the lug rotator ring 36 with respect to the sleeve 40 .
[0023] While the application of pressure is disclosed above as one triggering event to allow the lug 34 to move within the slot 38 , other events may also occur to allow the lug 34 to move within the slot 38 . In this case, the lock 20 may be configured to allow the lug 34 to move within the slot after the triggering event has occurred, so long as a predetermined condition is maintained. For example, but not by way of limitation, the triggering event may be a timer reaching a predetermined value, and the predetermined condition may be that the timer has not yet reached a second predetermined value.
[0024] Therefore, the present invention is well adapted to attain the ends and advantages mentioned as well as those that are inherent therein. The particular embodiments disclosed above are illustrative only, as the present invention may be modified and practiced in different but equivalent manners apparent to those skilled in the art having the benefit of the teachings herein. Furthermore, no limitations are intended to the details of construction or design herein shown, other than as described in the claims below. It is therefore evident that the particular illustrative embodiments disclosed above may be altered or modified and all such variations are considered within the scope and spirit of the present invention. Also, the terms in the claims have their plain, ordinary meaning unless otherwise explicitly and clearly defined by the patentee.
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A method of activating a downhole tool assembly. The downhole tool assembly has a sleeve with a continuous j-slot, a lug rotator ring configured to move axially relative to the sleeve and having a lug configured to move within the continuous j-slot, and a rupture disk configured to prevent the lug from moving within the continuous j-slot during run-in. The method includes lowering the downhole tool assembly into a well bore on a tool string, rupturing the rupture disk, allowing the lug to move within the continuous j-slot, and setting the downhole tool assembly by lifting upward and pushing downward on the tool string.
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This application claims the benefit, under 35 U.S.C. §119 of European Patent Application No. 15306297.1, filed Aug. 14, 2015.
TECHNICAL FIELD
The disclosure relates to color filter array used in plenoptic camera. More precisely, the disclosure relates to a technique for avoiding color artifacts when refocusing is done, especially when bokeh is present in images.
BACKGROUND
This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present invention that are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Even with plenoptic cameras, blur in some out-of-focus parts of an image still remain (and it is not possible to focus on in this places) due to the fact that these out-of-focus parts correspond to elements in the object space that are far from the focalization distance. In conventional photography, this blur is also named bokeh. As specified in Wikipedia for bokeh: “In out-of-focus areas, each point of light becomes an image of the aperture, generally a more or less round disc. Depending how a lens is corrected for spherical aberration, the disc may be uniformly illuminated, brighter near the edge, or brighter near the center. Lenses that are poorly corrected for spherical aberration will show one kind of disc for out-of-focus points in front of the plane of focus, and a different kind for points behind. This may actually be desirable, as blur circles that are dimmer near the edges produce less-defined shapes which blend smoothly with the surrounding image. The shape of the aperture has an influence on the subjective quality of bokeh as well. For conventional lens designs (with bladed apertures), when a lens is stopped down smaller than its maximum aperture size (minimum f-number), out-of-focus points are blurred into the polygonal shape formed by the aperture blades.”
It should be noted that “high quality” bokeh is viewed by most photographers as out of focus areas that are smooth rather than harsh. Moreover, in case of a color image, the quality of bokeh is linked to the homogeneity of colors in out-of-focus part of the image (i.e. without color artifacts). More details on Bokeh are described in the article entitled “ A Technical View of Bokeh ” by Harold M. Merklinger in Photo Techniques, May/June 1997, or in the technical note: “ Depth of Field and Bokeh ” by H. H. Nasse from the Camera Lens Division of the Zeiss company.
The obtaining of color images from a plenoptic camera (as the one depicted in FIG. 1 ) generally involves a color demosaicing process that consists in determining, for each pixel of the image sensor, the two color channel representations that have not been recorded by the pixel (i.e. the missing colors). Indeed, as for traditional digital cameras, a plenoptic camera comprises a color filter array (noted CFA) placed onto the image sensor so that each pixel only samples one of the three primary color values. Such Color Filter Array is usually a Bayer type CFA which is the repetition of a Bayer pattern that can be represented as a matrix
A = ( a ij ) 0 ≤ i ≤ 1 0 ≤ j ≤ 1 ′
with 2 lines and 2 column, where a 00 =a 11 =G (for Green), a 01 =R (for Red), and a 10 =B (for Blue). For example, the FIG. 18B of document US 2014/0146201 presents an image sensor recovered by a Color Filter array with the repetition of such Bayer pattern. Another Bayer pattern is represented by a matrix
B = ( b ij ) 0 ≤ i ≤ 1 0 ≤ j ≤ 1 ′
with 2 lines and 2 column, where b 01 =b 10 =G (for Green), b 00 =R (for Red), and b 11 =B (for Blue).
However, for a plenoptic camera, with a Color Filter array comprising the repetition of a Bayer pattern represented by a matrix of dimension M×M, and in the case that the size of the diameter of the micro-images (noted asp) is equal to k×M (i.e. k times M), where k is an integer, then it is not necessary to apply a color demosaicing process when obtaining a refocused image. Indeed, as detailed in FIG. 3( b ) , in this configuration, the sub-apertures images obtained from such plenoptic camera are mono-chromatic, and as the refocusing process comprises the adding of these sub-apertures images, there is no need to perform a demosaicing. The refocusing can be viewed as a demosaicing less operation.
However, this architecture for a plenoptic camera has a drawback: the quality of bokeh in refocused images obtained from light field data acquired by such plenoptic camera is bad (due to the presence of color artifacts), especially during a refocusing process on other part of the image. These color artifacts are very difficult to correct, and occur each time some objects are observed out-of-focus by the main lens of a plenoptic camera. More precisely, a bokeh corresponding to a white circle form of a white light source point could display the Bayer pattern when refocusing, instead of keeping the same homogeneous color (see FIGS. 4( a ) and 4( b ) of the present document). Another issue induced by such architecture is that when a change of viewpoint in images (especially in the extreme viewpoints) is done, as the subaperture images are monochromatic, it will not be possible to obtain a good demosaiced image.
For correcting such issue, one solution consists in applying a color filter array (based on a Bayer pattern) directly on the micro-lens of a plenoptic camera instead of positioning it on the image sensor itself. Such technique is briefly described in FIG. 3 of the present document, or in the FIG. 2 of document US 2015/0215593. However, there is a need for a solution that does not need to change the position of a CFA from the image sensor to the micro-lens array.
One skilled in the art, trying to keep the CFA positioned on the image sensor, would have breakdown the regularity of the CFA by using random patterns as mentioned in paragraph [0128] of document US 2014/0146201.
However, there is a need to determine which pattern configuration is well fitted for solving the previous mentioned problem.
SUMMARY OF THE DISCLOSURE
References in the specification to “one embodiment”, “an embodiment”, “an example embodiment”, indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
The present disclosure is directed to a plenoptic camera comprising a color filter array positioned on an image sensor comprising an array of pixels, said color filter array comprising a first filter comprising a set of unit elements, each unit element covering M×M pixels of said image sensor, with M an integer such that M≧2, said plenoptic camera further comprising a set of micro-lens, each micro-lens delivering a micro-lens image on said image sensor with a diameter equal to p=k×M (i.e. k times M), with k being an integer greater than or equal to two. The first filter is remarkable in that said set of unit elements comprises an initialization unit element being associated with a matrix
( c m , n ) 0 ≤ m < M 0 ≤ n < M
indicating a filter repartition (or pattern), where each coefficient c m,n is associated with a filter value, and in that the other unit elements are associated with matrixes with coefficients set to c (x+i)modM,(y+j)modM , for corresponding pixel (x,y,i,j) on said image sensor, where indexes x, y relate to indexation of a pixel in said image sensor, and indexes i,j relate to indexation of a micro-lens in said set of micro-lens (also named a micro-lens array).
In a preferred embodiment, said first filter is a color filter.
In a preferred embodiment, said initialization unit element is an extended Bayer filter pattern.
In a preferred embodiment, the plenoptic camera is remarkable in that M=2 and said initialization unit element is a Bayer filter pattern.
In a preferred embodiment, the plenoptic camera is remarkable in that M=2 and said initialization unit element is a RGBE (red, green, blue and emerald) filter pattern.
In a preferred embodiment, said color associated with a coefficient c m,n belongs to a group comprising cyan, yellow, green and magenta.
In a preferred embodiment, the plenoptic camera is remarkable in that M=2, and said initialization unit element is a CYYM (cyan, yellow, yellow and magenta) filter pattern.
In a preferred embodiment, the plenoptic camera is remarkable in that M=2, and said initialization unit element is a CYGM (cyan, yellow, green and magenta) filter pattern.
In a preferred embodiment, the plenoptic camera is remarkable in that said color filter array further comprises a second filter comprising another set of unit elements, each unit element of said another set covering pM×pM pixels of said image sensor, and being associated with polarization values or density values.
In a preferred embodiment, the plenoptic camera is remarkable in that said first filter is a polarization filter or a density filter.
In a preferred embodiment, the plenoptic camera is remarkable in that said color filter array further comprises a third filter comprising another set of unit elements, each unit element of said another set covering pM×pM pixels of said image sensor, and being associated with color values.
In a preferred embodiment, the plenoptic camera is remarkable in that wherein k≦4.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other aspects of the invention will become more apparent by the following detailed description of exemplary embodiments thereof with reference to the attached drawings in which:
FIG. 1 present schematically the main components comprised in a plenoptic camera that enables the acquisition of light field data on which the present technique can be applied;
FIG. 2 present another view of the image sensor disclosed in FIG. 1 ;
FIG. 3( a ) presents a Color-Filter-Array (positioned on an image sensor) which is commonly used to sample various colors with pixels performing a single measure;
FIG. 3( b ) presents sub-aperture images obtained from the micro-images from FIG. 3( a ) ;
FIG. 4( a ) illustrates a standard picture showing in focus part (bottom) and strongly de-focused light sources (top);
FIG. 4( b ) presents what appears at the level of strongly de-focused light sources when refocusing is performed;
FIG. 5( a ) presents a Color Filter Array according to one embodiment of the disclosure;
FIG. 5( b ) presents sub-aperture images obtained from the micro-images from FIG. 5( a ) ;
FIG. 6( a ) presents a Color Filter Array according to another embodiment of the disclosure;
FIG. 6( b ) presents sub-aperture images obtained from the micro-images from FIG. 6( a ) ;
FIG. 7 presents a Color Filter Array according to another embodiment of the disclosure;
FIG. 8( a ) presents a Color Filter Array according to another embodiment of the disclosure;
FIG. 8( b ) presents sub-aperture images obtained from the micro-images from FIG. 6( a ) ; and
FIG. 9 presents an example of device that can perform processing and refocusing of sub-aperture images based on micro-lens images disclosed in the present document.
DETAILED DESCRIPTION
FIG. 1 present schematically the main components comprised in a plenoptic camera that enables the acquisition of light field data on which the present technique can be applied.
More precisely, a plenoptic camera comprises a main lens referenced 101 , and an image sensor (i.e. an array of pixel sensors (for example a sensor based on CMOS technology)), referenced 104 . Between the main lens 101 and the image sensor 104 , a microlens array (i.e. a set of micro-lens) referenced 102 , that comprises a set of micro lenses referenced 103 , is positioned. It should be noted that optionally some spacers might be located between the micro-lens array around each lens and the image sensor to prevent light from one lens to overlap with the light of other lenses at the image sensor side. It should be noted that the main lens 101 can be a more complex optical system as the one depicted in FIG. 1 (as for example the optical system described in FIGS. 12 and 13 of document GB2488905) Hence, a plenoptic camera can be viewed as a conventional camera plus a micro-lens array set just in front of the image sensor as illustrated in FIG. 1 . The light rays passing through a micro-lens cover a part of the image sensor that records the radiance of these light rays. The recording by this part of the image sensor defines a micro-lens image.
FIG. 2 present what the image sensor 104 records. Indeed, in such view, it appears that the image sensor 104 comprises a set of pixels, referenced 201 . The light rays passing through a micro-lens cover a number of pixels 201 , and these pixels record the energy value of light rays that are incident/received.
Hence the image sensor 104 of a plenoptic camera records an image which comprises a collection of 2D small images (i.e. the micro-lens images referenced 202 ) arranged within a 2D image (which is also named a raw 4D light-field image). Indeed, each small image (i.e. the micro-lens images) is produced by a micro-lens (the micro-lens can be identified by coordinates (i,j) from the array of lens). Hence, the pixels of the light-field are associated with 4 coordinates (x,y,i,j). L(x,y,i,j) being the 4D light-field recorded by the image sensor illustrates the image which is recorded by the image sensor. Each micro-lens produces a micro-image represented by a circle (the shape of the small image depends on the shape of the micro-lenses which is typically circular). Pixel coordinates (in the image sensor) are labelled (x, y). p is the distance between 2 consecutive micro-images, p is not necessary an integer value in general (however, in the present disclosure, we consider that p is an integer. For example, in FIG. 2 , we have p=4). Micro-lenses are chosen such that p is larger than a pixel size 6 . Micro-lens images are referenced by their coordinate (i,j). Each micro-lens image samples the pupil of the main-lens with the (u, v) coordinate system. Some pixels might not receive any photons from any micro-lens especially if the shape of the micro-lenses is circular. In this case, the inter micro-lens space is masked out to prevent photons to pass outside from a micro-lens, resulting in some dark areas in the micro-images. If the micro-lenses have a square shape, no masking is needed). The center of a micro-lens image (i,j) is located on the image sensor at the coordinate (x i,j ,y i,j ). θ is the angle between the square lattice of pixel and the square lattice of micro-lenses, in FIG. 2 θ=0. Assuming the micro-lenses are arranged according to a regular square lattice, the (x i,j , y i,j ) can be computed by the following equation considering (x 0,0 , y 0,0 ) the pixel coordinate of the micro-lens image (0,0):
[ x i , j y i , j ] = p [ cos θ –sin θ sin θ cos θ ] [ i j ] + [ x 0 , 0 y 0 , 0 ] FIG. 2 also illustrates that an object from the scene is visible on several contiguous micro-lens images (dark dots). The distance between two consecutive views of an object is w, this distance is named the replication distance. Hence, an object is visible on r consecutive micro-lens images with:
r = ⌊ p p - w ⌋
r is the number of consecutive micro-lens images in one dimension. An object is visible in r 2 micro-lens images. Depending on the shape of the micro-lens image, some of the r 2 views of the object might be invisible.
More details related to plenoptic camera can be found out in the Section 4 entitled “ Image formation of a Light field camera ” in the article entitled “ The Light Field Camera: Extended Depth of Field, Aliasing, and Superresolution ” by Tom E. Bishop and Paolo Favaro, published in the IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol. 34, No 5, in May 2012.
It should be noted that micro-images can be re-organized into the so-called sub-aperture images. A sub-aperture images collects all 4D light-field pixels (i.e. the pixels that are positioned on the image sensor plane located behind the micro-lens) having the same (u, v) coordinates (the (u, v) coordinates correspond to coordinates on the main lens pupil).
In view of the FIG. 2 , let (I,J) being the number of micro-lenses covering the image sensor, and (N x ,N y ) the number of pixels of the image sensor. The number of sub-aperture images is equal to p×p. Each sub-aperture image have a size of (I,J)=(N x /p, N y /p) pixels.
FIG. 3( a ) presents a Color-Filter-Array (positioned on the image sensor 104 ) which is commonly used to sample various colors with pixels performing a single measure. The most common CFA pattern is the Bayer pattern made of 2 by 2 elements (i.e. the representation by the matrix B mentioned previously). For example, the FIG. 3( a ) presents a CFA which is made of the repetition of the matrix B, and where the size of the diameter of the micro-images 202 is equal to p=4. FIG. 3( b ) presents the sub-aperture images obtained from the micro-images 202 . It appears that all the sub-aperture images are monochromatic.
Therefore, in that case, the refocusing is particularly interesting.
Indeed, usually, the refocusing of images can be done via the addition of sub-aperture images extracted/derived from the micro-images 204 : refocused images can be computed by summing-up the sub-aperture images S(α, β) taking into consideration the disparity ρ focus for which objects at distance z focus are in focus. The sub-aperture pixels positioned at coordinates (α, β) of the sub-aperture image S(α, β, u, v) are projected to the pixel at coordinate (X,Y) according to the following equation:
[
X
Y
]
=
s
[
α
β
]
+
s
ρ
focus
[
u
v
]
The 4D light field pixels S(α, β, u, v) are projected into the 2D refocused image. Preliminarily a refocused image R and a refocused image weight R weight are set to 0. The size of the refocused images [N X ,N Y ] is set to s times the size of the sub-aperture images. The projection is performed by summing the projected pixels at the coordinate (X, Y) into the re-focused image. For each 4D light-field pixels projected, the refocused image weight is updated by adding 1 at the pixel coordinate (X, Y):
R ( X,Y )+= S (α,β, u,v )
R weight ( X,Y )+=1
The refocused image weight records how many 4D light-field pixels have been projected per coordinate (X, Y). After projecting all 4D light-field pixels of S(α, β, u, v), the refocused image R is divided by the refocused image weight R weight . This last step harmonizes the number of pixels received per coordinate (X, Y).
Since the projected coordinates (X, Y) are not necessarily integer coordinates, it is better to use interpolation technique to map a non-integer pixel coordinate (X, Y) into the grid of the refocused image R and refocused image weight R weight (same interpolation function must be used when projecting into R and R weight ). Interpolation technique are commonly used, descriptions can be found in Bilinear Interpolation (http://en.wikipedia.org/wiki/Bilinear_interpolation).
Hence, when ρ focus =0 (or equivalently w focus =∞) the re-focused image is obtained by superposing (i.e. adding) the sub-aperture images with no shifts. More generally, the use of a common CFA monted on the image sensor delivers de-mosaiced images whatever is the re-focusing parameter ρ focus . But this design is not able to produce good image for objects which remain out-of-focus (bokeh is affected by strong color artefacts).
Such remark concerning the refocusing that does not need to perform a demosacing operation can be generalized to the use of a CFA pattern made of a matrix of M×M elements each element being labeled c m,n with (m,n)ε[0,M[and with p (the diameter of the micro-images) equals to k·M, where k is an integer.
FIG. 4( a ) illustrates a standard picture showing in focus part (bottom) and strongly de-focused light sources (top). The strongly de-focused light-sources are actually showing the pupil of the main-lens since each light-source is like a Dirac function. If a plenoptic camera with a Bayer CFA set on top of the pixels with p=4 then the re-focused image produced by the plenoptic camera will show/display content of FIG. 4( b ) .
It is worth mentioning that in this case the purpose of the plenoptic camera is not to render this light-source in focus. But at least this light-source observed with a strong de-focus should be observed without the Bayer pattern visible.
As mentioned previously, one solution to overcome such issue would be to put the color filter directly on the micro-lenses. However, it should be noted that the refocused image must be demosaiced for ρ focus =−M, 0, +M . . . . The proposed technique corresponds to a special CFA to be positioned on the image sensor, in such way that the re-focused images are fully de-mosaiced for ρ focus =−M, 0, +M . . . .
Indeed, the proposed technique relates to a CFA with a pattern of size M×M dedicated to a plenoptic camera with a micro-images having the size of p=kM (with θ=0° the angle between the micro-lens array and the pixel array and k any positive integer).
Let us consider a CFA pattern with M 2 colors c m,n with (m, n)ε[0, M[. The color applied on the pixel (x,y,i,j) is set to c (x+i)modM,(y+j)modM . It results into a new CFA made of pM×pM covering the pixels. The original CFA is covering the p×p pixels, the other pixels belonging to the micro-lens (i,j) are covered with the original CFA but with “shuffled” colors.
The sub-aperture images are covered with the CFA of M 2 colors. But the starting colors of the sub-aperture image S uv is c u,v (and not c 0,0 for the common case where the original CFA is covering the pixels). This design makes re-focused images to be perfectly de-mosaiced for ρ focus =−M, 0, +M . . . . Also this new design is not affected by color artifacts for object observed out-of-focus.
FIG. 5( a ) presents a Color Filter Array with parameters p=M=2, positioned on an image sensor referenced 500 , and where the micro-images are referenced 501 . At the right top of the image sensor, the pattern is represented by a matrix
C = ( c ij ) 0 ≤ i ≤ 1 0 ≤ j ≤ 1 ′
with 2 lines and 2 column, where c 01 =c 10 =G (for Green), c 00 =R (for Red), and c 11 =B (for Blue). Then, instead of repeating this pattern along all the image sensor, shift color are performed as mentioned previously based on the equation c (x+i)mod2,(y+j)mod2 for the pixel (x,y,i,j).
FIG. 5( b ) presents sub-aperture images obtained from the processing of micro-lens images acquired via the configuration depicted in FIG. 5( a ) .
FIG. 6( a ) presents a Color Filter Array with parameters p=4, and M=2 positioned on an image sensor referenced 600 , and where the micro-images are referenced 601 . At the right top of the image sensor, the pattern is represented by a matrix
C = ( c ij ) 0 ≤ i ≤ 1 0 ≤ j ≤ 1 ′
with 2 lines and 2 column, where c 01 =c 10 =G (for Green), c 00 =R (for Red), and c 11 =B (for Blue). Then, instead of repeating this pattern along all the image sensor, shift color are performed as mentioned previously based on the equation c (x+i)mod4,(y+j)mod4 for the pixel (x,y,i,j).
FIG. 6( b ) presents sub-aperture images obtained from the processing of micro-lens images acquired via the configuration depicted in FIG. 6( a ) .
FIG. 7 illustrates how a CFA defined with M=3 is replicated on pixels covered by M×M consecutive micro-lenses. Here again, shift color is performed as mentioned previously based on the equation c (x+i)mod3,(y+j)mod3 for the pixel (x,y,i,j).
FIG. 8 ( a ) presents a Color Filter Array with parameters p=2, and M=2, positioned on an image sensor referenced 800 , and where the micro-images are referenced 801 .
In such embodiment of the disclosure, it is proposed a CFA pattern made of pM×pM elements from an initial (or first) CFA pattern (or unit element from a first set) c a,b made of M×M elements using shuffling as mentioned previously, and another CFA pattern (or unit element from a second set) that covers the pixels below M×M micro-lens images.
In such embodiment a second CFA pattern d a,b made of M×M elements is used to be covered on the micro-lens image (i modM, j modM). For instance this second CFA pattern could be made of polarization filter with specific orientations, or density filters made of various density as for instance 1, 0.1, 0.01 and 0.001.
Hence, a given pixel (x,y,i,j) of the image sensor is covered by the combined colors from the c and d CFA patterns following: c (x+i)modM,(y+j)modM ×d i modM,j modM where × denotes the combination between one element of c and one element of d. For instance the combination can be a superposition of the 2 elements.
The FIG. 8( a ) presents such embodiment where the first CFA pattern is made of the common Bayer pattern, and the second CFA pattern is made of a 2 transparent elements, and 2 element with a neutral density of 10%. This second CFA pattern is defined to capture High Dynamic Range image. The FIG. 8( b ) presents the sub-aperture images obtained from the configuration depicted in FIG. 8( a ) . One notices that the sub-aperture pixels are covered by the regular second CFA pattern. The advantage of the combination of a first shuffled CFA pattern and a second CFA pattern is to capture a Light-Field with extended filters with partial de-mosaicing.
One advantage of this embodiment is to ensure that the RGB colors are demosaiced on the refocused image for any disparity ρ=−M, 0, +M . . . . Moreover, HDR density are demosaiced for any disparity ρ=−M, 0, +M . . . . For the casual refocusing (disparity ρ=0) such embodiment guarantees ideal color demosaicing with available HDR. Such embodiment is especially dedicated to camera used to doing natural photography.
In another embodiment of the disclosure (not presented in the Figures), the first and second CFA patterns are swapped. More precisely, the coefficients c i,j correspond to polarization values or density values. And the coefficients d i modM,j modM correspond to color values. The advantage of this settings it to guaranty that the HDR density are demosaiced on the refocus image for any disparity ρ=−M, 0, +M. RGB colors are demosaiced for any disparity ρ=−M, 0, +M . . . . For the casual refocusing (with disparity ρ=0) this embodiment ensures a perfect HDR sampling with available color through de-mosaicing. Such embodiment is especially dedicated to industrial cameras that control a process with uncontrolled lighting.
FIG. 9 presents an example of device that can be used to perform processing and refocusing of sub-aperture images based on micro-lens images disclosed in the present document.
Such device referenced 900 comprises a computing unit (for example a CPU, for “Central Processing Unit”), referenced 901 , and one or more memory units (for example a RAM (for “Random Access Memory”) block in which intermediate results can be stored temporarily during the execution of instructions a computer program, or a ROM block in which, among other things, computer programs are stored, or an EEPROM (“Electrically-Erasable Programmable Read-Only Memory”) block, or a flash block) referenced 902 . Computer programs are made of instructions that can be executed by the computing unit. Such device 900 can also comprise a dedicated unit, referenced 903 , constituting an input-output interface to allow the device 900 to communicate with other devices. In particular, this dedicated unit 903 can be connected with an antenna (in order to perform communication without contacts), or with serial ports (to carry communications “contact”). It should be noted that the arrows in FIG. 9 signify that the linked unit can exchange data through buses for example together.
In an alternative embodiment, some or all of the steps of the method previously described, can be implemented in hardware in a programmable FPGA (“Field Programmable Gate Array”) component or ASIC (“Application-Specific Integrated Circuit”) component.
In one embodiment of the disclosure, the electronic device depicted in FIG. 9 can be comprised in a camera device that is configure to capture images (i.e. a sampling of a light field). These images are stored on one or more memory units. Hence, these images can be viewed as bit stream data (i.e. a sequence of bits). Obviously, a bit stream can also be converted on byte stream and vice versa.
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A plenoptic camera is proposed having a color filter array positioned on an image sensor with an array of pixels, the color filter array having a first filter with a set of unit elements, each unit element covering M×M pixels of the image sensor, with M an integer such that M≧2. The plenoptic camera further includes a set of micro-lens, each micro-lens delivering a micro-lens image on the image sensor with a diameter equal to p=k×M, with k being an integer greater than or equal to two. The first filter is remarkable in that the set of unit elements comprises an initialization unit element being associated with a matrix
( c m , n ) 0 ≤ m < M 0 ≤ n < M
indicating a filter repartition (or pattern), where each coefficient c m,n is associated with a filter value, and in that the other unit elements are associated with matrixes with coefficients set to c (x+i)modM,(y+j)modM , for corresponding pixel (x,y,i,j) on the image sensor, where indexes x, y relate to indexation of a pixel in the image sensor, and indexes i,j relate to indexation of a micro-lens in the set of micro-lens.
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CROSS REFERENCE TO RELATED APPLICATIONS
This is a U.S. national stage of International Application No. PCT/JP2011/065146, filed on Jul. 1, 2011. Priority under 35 U.S.C. §119(a) and 35 U.S.C. §365(b) is claimed from Japanese Application No. 2010-152606, filed Jul. 5, 2010, the disclosure of which is also incorporated herein by reference.
TECHNICAL FIELD
The present invention relates to a medium feeding direction switching mechanism by which a feeding direction of a carried information recording medium is switched and relates to a medium issuing and collecting device which is provided with the medium feeding direction switching mechanism.
BACKGROUND
Conventionally, a card issuing device in which a card accommodated in a card stacker is issued has been known (see, for example, Patent Literature 1). The card issuing device described in Patent Literature 1 includes a first feed roller and a second feed roller for carrying a card. The first feed roller and the second feed roller are disposed with a predetermined distance in a feeding direction of a card. Further, the card issuing device includes a first counter roller which is oppositely disposed to the first feed roller and a second counter roller which is oppositely disposed to the second feed roller. The first counter roller and the second counter roller are rotatably supported by fixed shafts which are fixed to a plate. Further, a motor is connected with the plate through a gear train and the plate is capable of turning over a predetermined angle with a rotation center of the second feed roller as a turning center.
In the card issuing device described in Patent Literature 1, when the first and the second feed rollers are rotated in a forward direction in a state that the first feed roller and the first counter roller abut each other and the second feed roller and the second counter roller abut each other, a card is issued from a card stacker. Further, the card issuing device is provided with a function for collecting a card and, when a card is to be collected, the plate is turned in a state that a card is sandwiched between the first feed roller and the first counter roller and between the second feed roller and the second counter roller. When the plate is turned, the second counter roller is moved along the surface of the second feed roller and the first counter roller is separated from the first feed roller. Further, in this state, when the first and the second feed rollers are rotated in a reverse direction, a card sandwiched between the second feed roller and the second counter roller is collected to a lower side portion of the card issuing device. As described above, in the card issuing device described in Patent Literature 1, a feeding direction of a carried card is switched by turning the plate.
[PTL 1] Japanese Patent No. 4186033
However, in the card issuing device described in Patent Literature 1, a feeding direction of a carried card is switched by turning the plate and thus a gear train and a motor for turning the plate are required. In other words, in the card issuing device described in Patent Literature 1, a structure for switching a feeding direction of a carried card is complicated.
SUMMARY
In view of the problem described above, at least an embodiment of the present invention provides a medium feeding direction switching mechanism which is capable of switching a feeding direction of a carried information recording medium with a simple structure. Further, at least an embodiment of the present invention provides a medium issuing and collecting device which is provided with the medium feeding direction switching mechanism.
In order to solve the above problem, at least an embodiment of the present invention provides a medium feeding direction switching mechanism for switching a feeding direction of a carried information recording medium including a feed roller which is structured to abut with an information recording medium for carrying the information recording medium, a pinch roller which is oppositely disposed to the feed roller for sandwiching and carrying the information recording medium together with the feed roller, an urging member which urges the pinch roller toward the feed roller, a bearing which rotatably supports a rotation shaft rotating together with the pinch roller or a support shaft which rotatably supports the pinch roller, a first holding member which holds the urging member, and a second holding member which holds the support shaft or the bearing so that the pinch roller is capable of turning with a rotation center of the feed roller as a turning center between a first facing position where the pinch roller and the feed roller are facing each other in a predetermined first direction and a second facing position where the pinch roller and the feed roller are each other in a predetermined second direction that is inclined with respect to the first direction. One end of the urging member is engaged with the support shaft or the bearing and the other end of the urging member is engaged with the first holding member and, when the feed roller is rotated in a forward direction, the pinch roller located at the second facing position is moved to the first facing position and, when the feed roller is rotated in a reverse direction, the pinch roller located at the first facing position is moved to the second facing position.
The medium feeding direction switching mechanism in accordance with at least an embodiment of the present invention includes the feed roller, the pinch roller, and the urging member which urges the pinch roller toward the feed roller. Further, in at least an embodiment of the present invention, the pinch roller is capable of turning between the first facing position and the second facing position with the rotation center of the feed roller as a turning center. In addition, in at least an embodiment of the present invention, when the feed roller is rotated in the forward direction, the pinch roller located at the second facing position is moved to the first facing position and, when the feed roller is rotated in the reverse direction, the pinch roller located at the first facing position is moved to the second facing position.
In other words, in at least an embodiment of the present invention, when the feed roller is rotated in the reverse direction, the pinch roller located at the first facing position is moved to the second facing position by appropriately setting the friction coefficients of the feed roller, the pinch roller and the information recording medium, the urging force of the urging member and the like. Further, in at least an embodiment of the present invention, when the feed roller is rotated in the forward direction, the pinch roller located at the second facing position is moved to the first facing position by appropriately setting the friction coefficients of the feed roller, the pinch roller and the information recording medium, the urging force of the urging member and the like. Further, in at least an embodiment of the present invention, the second direction is inclined with respect to the first direction and thus, when the pinch roller is moved between the first facing position and the second facing position, a feeding direction of the information recording medium carried by the feed roller and the pinch roller is switched. Therefore, in the medium feeding direction switching mechanism according to at least an embodiment of the present invention, a feeding direction of the carried information recording medium can be switched with a simple structure with the use of the urging member.
In at least an embodiment of the present invention, it is preferable that a third facing position where the pinch roller and the feed roller are each other so that a rotation center of the feed roller, one end of the urging member and the other end of the urging member are disposed in a substantially straight line is located between the first facing position and the second facing position. According to this structure, the pinch roller can be held at the first facing position and the second facing position by the urging force of the urging member and the pinch roller is stably held at the first facing position and the second facing position. According to this structure, in a case that the friction coefficients of the feed roller, the pinch roller and the information recording medium, the urging force of the urging member and the like are appropriately set, when the feed roller is rotated in the reverse direction, the pinch roller is moved from the first facing position to the third facing position by a frictional force between the feed roller and the information recording medium, a frictional force between the pinch roller and the information recording medium and the like, or by a frictional force between the feed roller and the pinch roller and the like and, when the pinch roller has passed the third facing position, the pinch roller is moved to the second facing position mainly by the urging force of the urging member. Further, in a case that the friction coefficients of the feed roller, the pinch roller and the information recording medium, the urging force of the urging member and the like are appropriately set, when the feed roller is rotated in the forward direction, the pinch roller is moved from the second facing position to the third facing position by a frictional force between the feed roller and the information recording medium, a frictional force between the pinch roller and the information recording medium and the like, or by a frictional force between the feed roller and the pinch roller and the like and, when the pinch roller has passed the third facing position, the pinch roller is moved to the first facing position mainly by the urging force of the urging member.
In at least an embodiment of the present invention, it is preferable that the third facing position is located at a substantially middle position between the first facing position and the second facing position. According to this structure, in comparison with a case that the third facing position is displaced to the first facing position side or to the second facing position side, the friction coefficients of the feed roller, the pinch roller and the information recording medium, the urging force of the urging member and the like for moving the pinch roller from the first facing position to the third facing position, and the friction coefficients of the feed roller, the pinch roller and the information recording medium, the urging force of the urging member and the like for moving the pinch roller from the second facing position to the third facing position are easily set. Therefore, the pinch roller is easily moved between the first facing position and the second facing position.
In at least an embodiment of the present invention, for example, the second holding member is formed with a guide part for guiding the support shaft or the bearing so that the pinch roller is capable of turning with the rotation center of the feed roller as the turning center between the first facing position and the second facing position, and the first holding member is fixed to the second holding member or the first holding member is integrally formed with the second holding member. Further, in this case, it is preferable that the guide part is formed on both end sides of the support shaft or the rotation shaft. According to this structure, the support shaft or the bearing is appropriately guided between the first facing position and the second facing position by the guide part.
In at least an embodiment of the present invention, it is preferable that the medium feeding direction switching mechanism includes a sorting member which is capable of abutting with an end part in a feeding direction of the information recording medium sandwiched between the feed roller and the pinch roller when the feed roller is rotated in a reverse direction and the sorting member guides the information recording medium so that the pinch roller is moved to the second facing position. According to this structure, the pinch roller is easily moved from the first facing position to the second facing position by utilizing the sorting member.
In at least an embodiment of the present invention, the sorting member is, for example, capable of turning between a position at which the sorting member closes a first feeding path that is a feeding path for the information recording medium when the feed roller is rotated in the forward direction and a position at which the sorting member opens the first feeding path, and the sorting member is urged in a direction for closing the first feeding path and, when the feed roller is rotated in the forward direction, the information recording medium abuts the sorting member and the sorting member opens the first feeding path.
In at least an embodiment of the present invention, it is preferable that the medium feeding direction switching mechanism includes a feeding guide which structures a medium feeding passage where the information recording medium is carried. The feeding guide is formed with an escape part for preventing the information recording medium from abutting with the feeding guide when the pinch roller is moved between the first facing position and the second facing position in a state that the information recording medium is sandwiched between the feed roller and the pinch roller. According to this structure, even when the pinch roller is moved between the first facing position and the second facing position in a state that an information recording medium is sandwiched between the feed roller and the pinch roller, the pinch roller is easily moved between the first facing position and the second facing position.
The medium feeding direction switching mechanism in accordance with at least an embodiment of the present invention may be utilized in a medium issuing and collecting device which includes a medium accommodating part in which an information recording medium for being sent out toward the medium feeding direction switching mechanism is accommodated and a medium collecting part in which the information recording medium is to be collected. In the medium issuing and collecting device, when the feed roller is rotated in a forward direction, the information recording medium which is sent out from the medium accommodating part is issued and, when the feed roller is rotated in a reverse direction, the information recording medium is collected in the medium collecting part. In this case, the medium issuing and collecting device is, for example, provided with a recording and reproducing part in which recording of information is performed to the information recording medium that is sent out from the medium accommodating part and reproduction of information recorded in the information recording medium is performed. The feed roller is rotated in the forward direction or the reverse direction based on a reproduction result in the recording and reproducing part. In the medium issuing and collecting device, since a structure of the medium feeding direction switching mechanism is simplified, a structure of the medium issuing and collecting device is simplified. Therefore, the size of the medium issuing and collecting device can be reduced.
As described above, in the medium feeding direction switching mechanism in accordance with at least an embodiment of the present invention, a feeding direction of a carried information recording medium is switched with a simple structure. Further, in the medium issuing and collecting device in accordance with at least an embodiment of the present invention, since a structure of the medium feeding direction switching mechanism is simplified, a structure of the device is simplified and the size of the device is reduced.
BRIEF DESCRIPTION OF DRAWINGS
Embodiments will now be described, by way of example only, with reference to the accompanying drawings which are meant to be exemplary, not limiting, and wherein like elements are numbered alike in several Figures, in which:
FIG. 1 is a perspective view showing a medium issuing and collecting device in accordance with an embodiment of the present invention.
FIG. 2 is an explanatory side view showing a schematic structure of a part of the medium issuing and collecting device shown in FIG. 1 .
FIG. 3 is an explanatory perspective view showing a structure of a medium feeding direction switching mechanism shown in FIG. 2 .
FIG. 4 is an enlarged view showing an “E” part in FIG. 1 .
FIG. 5 is an enlarged view showing an “F” part in FIG. 2 .
FIG. 6 is an enlarged view showing a “G” part in FIG. 5 .
FIG. 7 is an explanatory view showing an urging member in accordance with another embodiment of the present invention.
FIG. 8 is an explanatory view showing an urging member in accordance with another embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
Embodiments of the present invention will be described below with reference to the accompanying drawings.
Schematic Structure of Medium Issuing and Collecting Device
FIG. 1 is a perspective view showing a medium issuing and collecting device 1 in accordance with an embodiment of the present invention. FIG. 2 is an explanatory side view showing a schematic structure of a part of the medium issuing and collecting device 1 shown in FIG. 1 .
The medium issuing and collecting device 1 in this embodiment is provided with a card issuing function for issuing a card 2 , which is an information recording medium, and a card collecting function for collecting a card 2 . In this embodiment, an issued card 2 is ejected to an “X1” direction side in FIGS. 1 and 2 . In the following descriptions, the “X1” direction side in FIG. 1 is set to be a “front” side in the medium issuing and collecting device 1 and an “X2” direction side which is an opposite side to the “X1” direction side is set to be a “rear” side in the medium issuing and collecting device 1 .
As shown in FIGS. 1 and 2 , the medium issuing and collecting device 1 includes a recording and reproducing part 3 which performs recording of information to a card 2 and reproduction of recorded information from a card 2 , a card sending-out part 4 which sends out a card 2 toward the recording and reproducing part 3 , a card collecting part 5 as a medium collecting part which collects a card 2 , and a feeding direction switching mechanism 6 as a medium feeding direction switching mechanism in which a feeding direction of a card 2 when the card 2 is to be issued and a feeding direction of a card 2 when the card 2 is to be collected are switched.
The recording and reproducing part 3 , the card collecting part 5 and the feeding direction switching mechanism 6 are disposed on the front side of the medium issuing and collecting device 1 and the card sending-out part 4 is disposed on the rear side of the medium issuing and collecting device 1 . A card feeding passage 7 as a medium feeding passage where a card 2 is carried is formed in an inside of a front side portion of the medium issuing and collecting device 1 .
The card 2 is, for example, a rectangular card made of vinyl chloride whose thickness is about 0.7-0.8 mm. The card 2 in this embodiment is a non-contact type IC card and the card 2 is incorporated with an antenna for communication. A magnetic stripe may be formed on the surface of the card 2 or an IC chip may be fixed to the card 2 . Further, the card 2 may be a PET (polyethylene terephthalate) card whose thickness is about 0.18-0.36 mm or a paper card having a predetermined thickness.
The recording and reproducing part 3 includes an antenna 9 for communication and a control circuit board 10 . The antenna 9 and the control circuit board 10 are fixed to the frame 11 which structures a front side portion of the medium issuing and collecting device 1 . The card collecting part 5 is a collecting container for collecting a card 2 and a part on the lower end side of the frame 11 is structured as the card collecting part 5 . A space is formed in an inside of the card collecting part 5 and collected cards 2 are stacked and accommodated in this space. The card feeding passage 7 is formed in the inside of the frame 11 . The frame 11 in this embodiment is a feeding guide which structures the card feeding passage 7 .
The card sending-out part 4 includes a card accommodating part 12 as a medium accommodating part in which a plurality of cards 2 before issued is stacked and accommodated in an upper and lower direction, a sending-out roller 13 for sending out a card accommodated at the lowest position among a plurality of the cards 2 accommodated in the card accommodating part 12 to a front face side of the card sending-out part 4 , a sending-out roller 14 for further sending out the card 2 which is sent out by the sending-out roller 13 to the front side of the medium issuing and collecting device 1 , a pad roller 15 which is oppositely disposed to the sending-out roller 14 and is urged toward the sending-out roller 14 , and card separating rollers 16 and 17 for preventing two cards 2 from being sent out in a stacked state from the card accommodating part 12 .
The card accommodating part 12 is formed in a rectangular box-like shape whose a part of a side face and upper face are opened. A gate through which a card 2 accommodated in the card accommodating part 12 is passed toward the front side is formed between a bottom face part 12 a of the card accommodating part 12 and a lower end of its front side wall part 12 b . The sending-out roller 13 is an eccentric roller and an upper end side of the sending-out roller 13 is disposed in an inside of a through hole which is formed in the bottom face part 12 a . The sending-out roller 13 is connected with a motor not shown. The sending-out roller 14 is connected with a motor not shown. The pad roller 15 is disposed so as to face an upper end of the sending-out roller 14 .
The card separating rollers 16 and 17 are disposed between the sending-out roller 14 and the pad roller 15 and the card accommodating part 12 . Further, the card separating rollers 16 and 17 are disposed so as to be each other in the upper and lower direction. In this embodiment, the card separating roller 16 is disposed on a lower side and the card separating roller 17 is disposed on an upper side. When a card 2 is to be sent out from the card accommodating part 12 , the card separating roller 16 is rotated in a direction for feeding the card 2 to the front side (in other words, in a clockwise direction in FIG. 2 ) and the card separating roller 17 is rotated in a direction for feeding the card 2 to the rear side (in other words, in the clockwise direction in FIG. 2 ). As described above, the card separating rollers 16 and 17 which are oppositely disposed to each other in the upper and lower direction are rotated in the same direction as each other and thus, when two cards 2 are sent out in a stacked state from the card accommodating part 12 , a card 2 on an upper side is returned to the inside of the card accommodating part 12 .
Structure of Medium Feeding Direction Switching Mechanism
FIG. 3 is an explanatory perspective view showing a structure of the medium feeding direction switching mechanism 6 shown in FIG. 2 . FIG. 4 is an enlarged view showing an “E” part in FIG. 1 . FIG. 5 is an enlarged view showing an “F” part in FIG. 2 . FIG. 6 is an enlarged view showing a “G” part in FIG. 5 .
The feeding direction switching mechanism 6 includes a feed roller 20 that abuts a card 2 for carrying the card 2 , a pinch roller 21 which is oppositely disposed to the feed roller 20 , two torsion coil springs 22 as an urging member for urging the pinch roller 21 toward the feed roller 20 , and a flapper 23 as a sorting member by which a card 2 is guided to the card accommodating part 12 when the feed roller 20 is rotated in a direction so that the card 2 is carried to the rear side.
The feed roller 20 is disposed on the front side with respect to the recording and reproducing part 3 in the front and rear direction. As shown in FIG. 3 , a rotation shaft 24 to which the feed roller 20 is fixed is fixed with one gear structuring a gear train 25 and the feed roller 20 is connected with a motor 26 through the gear train 25 . A distance between the feed roller 20 and the sending-out roller 14 in the front and rear direction is set to be shorter than a length in the front and rear direction of a card 2 in the medium issuing and collecting device 1 .
The pinch roller 21 is urged toward the feed roller 20 from a roughly upper side by an urging force of the torsion coil spring 22 and a card 2 is sandwiched between the feed roller 20 and the pinch roller 21 and is carried by the feed roller 20 and the pinch roller 21 . Further, the pinch roller 21 is rotatably supported by a support shaft 27 .
Both end sides of the support shaft 27 are held by the frame 11 . The frame 11 is formed with a guide groove 11 a as a guide part into which the support shaft 27 is inserted as shown in FIG. 4 . The guide groove 11 a is formed at two positions and each of both end sides of the support shaft 27 is inserted into the guide groove 11 a . The frame 11 in this embodiment is a second holding member which holds the support shaft 27 .
A position of the pinch roller 21 is set to be a first facing position “P 1 ” where the pinch roller 21 and the feed roller 20 are each other in the upper and lower direction as shown by the solid line in FIGS. 5 and 6 . Further, a position of the pinch roller 21 is set to be a second facing position “P 2 ” where the pinch roller 21 and the feed roller 20 are each other in an inclined state by an angle “θ” in a counterclockwise direction in FIGS. 5 and 6 with respect to the upper and lower direction (in other words, in a direction which is inclined by an angle “θ” to the rear side) as shown by the two-dot chain line in FIGS. 5 and 6 . In this case, the guide groove 11 a performs a function for guiding the support shaft 27 so that the pinch roller 21 is capable of being turned between the first facing position “P 1 ” and the second facing position “P 2 ” with the rotation center “C 1 ” of the feed roller 20 as a turning center. The guide groove 11 a is formed in a roughly rectangular shape or a roughly circular arc shape whose center is the rotation center “C 1 ” of the feed roller 20 . The angle “θ” is an acute angle. Further, the angle “θ” is a relatively small angle and, for example, in a range from about 15° to about 20°.
One end of the torsion coil spring 22 (specifically, a tip end of one arm of the torsion coil spring 22 ) is formed as an engagement part 22 a which is formed in a ring shape. Further, the other end of the torsion coil spring 22 (specifically, a tip end of the other arm of the torsion coil spring 22 ) is formed as an engagement part 22 b which is formed in a ring shape. In this embodiment, each of the both end sides of the support shaft 27 is inserted into the engagement part 22 a and each of the engagement parts 22 a is engaged with each of the both end sides of the support shaft 27 . In other words, in this embodiment, the torsion coil spring 22 is disposed on each of the both end sides of the support shaft 27 . A fixed shaft 28 which is fixed to the frame 11 is inserted into the engagement part 22 b and the engagement part 22 b is engaged with the fixed shaft 28 . The engagement part 22 a is relatively turnable with respect to the support shaft 27 and the engagement part 22 b is relatively turnable with respect to the fixed shaft 28 . The fixed shaft 28 in this embodiment is a first holding member which holds the torsion coil spring 22 . The fixed shaft 28 may be integrally formed with the frame 11 .
The fixed shaft 28 is disposed on an upper side with respect to the pinch roller 21 . Further, as shown in FIG. 6 , the fixed shaft 28 is fixed to the frame 11 so that the center “C 2 ” of the support shaft 27 when the pinch roller 21 is located at a substantially middle position between the first facing position “P 1 ” and the second facing position “P 2 ” is disposed on the straight line “L” which is formed by connecting the rotation center “C 1 ” of the feed roller 20 with the center “C 3 ” of the fixed shaft 28 . In other words, a third facing position “P 3 ” where the pinch roller 21 and the feed roller 20 are facing each other is set between the first facing position “P 1 ” and the second facing position “P 2 ” so that the rotation center “C 1 ” of the feed roller 20 , the engagement part 22 a of the torsion coil spring 22 , and its engagement part 22 b are disposed on a substantially straight line. The engagement part 22 b of the torsion coil spring 22 is disposed on the straight line “L” which is inclined by an angle “θ/2” with respect to the upper and lower direction in the counterclockwise direction in FIG. 6 . When the pinch roller 21 is located at the third facing position, the urging force of the torsion coil spring 22 becomes the maximum.
The flapper 23 is disposed on the front side with respect to the sending-out roller 14 . The flapper 23 is turnably supported by a fixed shaft 29 which is fixed to the frame 11 . Further, the flapper 23 is formed with a closing part 23 a for closing a feeding path “R 1 ” for a card 2 , which is carried to the front side from the card sending-out part 4 , so as to protrude from the fixed shaft 29 in a roughly oblique upper direction. In this embodiment, the flapper 23 is supported by the fixed shaft 29 so that the flapper 23 is turnable between a closing position at which the closing part 23 a closes the feeding path “R 1 ” as shown by the solid line in FIG. 5 and an opened position at which the closing part 23 a opens the feeding path “R 1 ” as shown by the two-dot chain line in FIG. 5 . Further, the flapper 23 is urged in a direction in which the closing part 23 a closes the feeding path “R 1 ” (in other words, in a counterclockwise direction in FIG. 5 ) by an urging member not shown or by its own weight. The feeding path “R 1 ” in this embodiment is a first feeding path.
In this embodiment, when a card 2 is to be sent out from the card sending-out part 4 , the feed roller 20 is rotated in a clockwise direction in FIG. 5 . Further, when the card 2 is sent out from the card sending-out part 4 , the card 2 abuts an upper face side of the closing part 23 a and, as shown by the two-dot chain line in FIG. 5 , the closing part 23 a is turned to the position where the feeding path “R 1 ” is opened. In other words, when the feed roller 20 is rotated in the clockwise direction in FIG. 5 , the card 2 abuts the upper face side of the closing part 23 a to set the flapper 23 to open the feeding path “R 1 ”.
Further, in this embodiment, friction coefficients of the feed roller 20 and the pinch roller 21 , an urging force of the torsion coil spring 22 , the angle “θ” and the like are set so that, when the feed roller 20 is rotated in the clockwise direction in FIG. 5 in a state that the pinch roller 21 located at the second facing position “P 2 ” abuts the feed roller 20 , the pinch roller 21 is moved to the first facing position “P 1 ” along an outer peripheral face of the feed roller 20 and, in addition, so that a force by which the pinch roller 21 located at the second facing position “P 2 ” passes through the third facing position, a frictional force between the pinch roller 21 and the support shaft 27 , and a frictional force between the feed roller 20 and the pinch roller 21 become larger in this order.
In a case that the pinch roller 21 located at the second facing position “P 2 ” is to be moved to the first facing position “P 1 ”, the pinch roller 21 is moved from the second facing position “P 2 ” to the third facing position by the frictional force between the feed roller 20 and the pinch roller 21 and the like and, when the pinch roller 21 has passed the third facing position, the pinch roller 21 is moved to the first facing position “P 1 ” mainly by the urging force of the torsion coil spring 22 . In other words, the pinch roller 21 is moved from the second facing position “P 2 ” to the first facing position “P 1 ” by utilizing a so-called toggle motion in which the third facing position is its toggle point. Further, the pinch roller 21 is hardly rotated with the support shaft 27 as a center during the pinch roller 21 is moved from the second facing position “P 2 ” to the first facing position “P 1 ” and, after moved to the first facing position “P 1 ”, the pinch roller 21 is rotated with the support shaft 27 as a center. Further, when the pinch roller 21 is located at the first facing position “P 1 ”, the pinch roller 21 is held at the first facing position “P 1 ” by the urging force of the torsion coil spring 22 , and the pinch roller 21 and the feed roller 20 are each other in a direction substantially perpendicular to the front and rear direction which is a feeding direction of a card 2 when the card 2 is to be issued (in other words, in the upper and lower direction).
Further, in this embodiment, the friction coefficients of the feed roller 20 and the pinch roller 21 , the urging force of the torsion coil spring 22 , the angle “θ” and the like are set so that, when the feed roller 20 is rotated in a counterclockwise direction in FIG. 5 in a state that a card 2 whose rear end of the card 2 is disposed on the front side with respect to the closing part 23 a is sandwiched between the pinch roller 21 located at the first facing position “P 1 ” and the feed roller 20 , the pinch roller 21 is moved to the second facing position “P 2 ” along the outer peripheral face of the feed roller 20 and, so that a force by which the pinch roller 21 located at the first facing position “P 1 ” passes through the third facing position, the frictional force between the pinch roller 21 and the support shaft 27 , and the frictional force between the feed roller 20 and the pinch roller 21 become larger in this order.
When the pinch roller 21 located at the first facing position “P 1 ” is to be moved to the second facing position “P 2 ”, the pinch roller 21 is moved from the first facing position “P 1 ” to the third facing position by a frictional force between the feed roller 20 and the card 2 and by a frictional force between the pinch roller 21 and the card 2 and, when the pinch roller 21 has passed the third facing position, the pinch roller 21 is moved to the second facing position “P 2 ” mainly by the urging force of the torsion coil spring 22 . In other words, the pinch roller 21 is moved from the first facing position “P 1 ” to the second facing position “P 2 ” by utilizing a so-called toggle motion in which the third facing position is its toggle point. Further, the pinch roller 21 is hardly rotated with the support shaft 27 as a center during the pinch roller 21 is moved from the first facing position “P 1 ” to the second facing position “P 2 ” and, after moved to the second facing position “P 2 ”, the pinch roller 21 is rotated with the support shaft 27 as a center. Further, when the pinch roller 21 is located at the second facing position “P 2 ”, the pinch roller 21 is held at the second facing position “P 2 ” by the urging force of the torsion coil spring 22 , and the pinch roller 21 and the feed roller 20 are each other in a direction substantially perpendicular to the feeding direction of a card 2 when the card 2 is to be collected to the card collecting part 5 .
Further, when the feed roller 20 is rotated in the counterclockwise direction in FIG. 5 in a state that a card 2 is sandwiched between the pinch roller 21 and the feed roller 20 , a rear end of the card 2 abuts a lower side face of the closing part 23 a which closes the feeding path “R 1 ”. When the rear end of the card 2 abuts the lower side face of the closing part 23 a , a moment in the counterclockwise direction in FIG. 5 is occurred on the front end side of the card 2 by an elastic force of the card 2 with the abutting part of the closing part 23 a with the card 2 as a supporting point. Movement to the second facing position “P 2 ” of the pinch roller 21 sandwiching the card 2 together with the feed roller 20 is assisted by this moment occurred on the front end side of the card 2 . In other words, the flapper 23 in this embodiment performs a function for guiding a card 2 so that the pinch roller 21 is moved to the second facing position “P 2 ”. Further, in this embodiment, the flapper 23 is disposed so that, when the pinch roller 21 is moved to the second facing position “P 2 ”, the rear end side of the card 2 does not abut the lower side face of the closing part 23 a.
As described above, in this embodiment, when the pinch roller 21 is turned and moved to the first facing position “P 1 ” or the second facing position “P 2 ” with the rotation center “C 1 ” of the feed roller 20 as a center, the feeding direction of a card 2 is switched to an oblique direction which is inclined with respect to the front and rear direction or to the front and rear direction.
In accordance with an embodiment of the present invention, the friction coefficients of the feed roller 20 and the pinch roller 21 , the urging force of the torsion coil spring 22 , the angle “θ” and the like may be set so that, after the rear end of a card 2 abuts a lower side face of the closing part 23 a , the pinch roller 21 is capable of passing through the third facing position by utilizing a moment occurred on the front end side of the card 2 in the counterclockwise direction in FIG. 5 . In other words, the friction coefficients of the feed roller 20 and the pinch roller 21 , the urging force of the torsion coil spring 22 , the angle “θ” and the like may be set so that, when the feed roller 20 is rotated in the counterclockwise direction in FIG. 5 , although the pinch roller 21 cannot pass through the third facing position only by the frictional force between the feed roller 20 and the card 2 and the frictional force between the pinch roller 21 and the card 2 , the pinch roller 21 is capable of passing through the third facing position when the moment is occurred on the front end side of the card 2 .
As shown in FIG. 5 , a recessed part 11 b which is recessed toward an upper side is formed on an upper face of the card feeding passage 7 on a front side with respect to the feed roller 20 and the pinch roller 21 . In other words, the frame 11 is formed with the recessed part 11 b . The recessed part 11 b is an escape part for preventing a card 2 from abutting with the frame 11 when the feed roller 20 is rotated in the counterclockwise direction in FIG. 5 in a state that the card 2 is sandwiched between the feed roller 20 and the pinch roller 21 and the pinch roller 21 is moved from the first facing position “P 1 ” to the second facing position “P 2 ”.
Schematic Operation of Medium Issuing and Collecting Device
A schematic operation for issuing and collecting a card 2 in the medium issuing and collecting device 1 structured as described above will be described below. In the following descriptions, rotation of the feed roller 20 in the clockwise direction in FIG. 5 is referred to as a forward rotation and rotation of the feed roller 20 in the counterclockwise direction in FIG. 5 is referred to as a reverse rotation.
In the medium issuing and collecting device 1 , when a card 2 accommodated in the card accommodating part 12 is to be issued, first, a card 2 is sent out from the card sending-out part 4 toward the recording and reproducing part 3 and the feeding direction switching mechanism 6 by the sending-out rollers 13 and 14 and the pad roller 15 . The card 2 having been sent out is temporarily stopped on a lower side of the recording and reproducing part 3 . In this case, a front end side of the card 2 is sandwiched between the feed roller 20 and the pinch roller 21 and a rear end side of the card 2 is sandwiched between the sending-out roller 14 and the pad roller 15 .
In this state, communication is performed between an antenna incorporated into the card 2 and the antenna 9 and predetermined information is recorded in the card 2 . Further, in order to confirm whether appropriate information is recorded in the card 2 or not, communication is performed between the antenna incorporated into the card 2 and the antenna 9 and the information recorded in the card 2 is reproduced. As a result of reproduction of the information, when the recorded information in the card 2 is confirmed to be the information to be recorded, the feed roller 20 is rotated in the forward direction to issue the card 2 .
On the other hand, when the recorded information in the card 2 cannot be reproduced or, when the recorded information in the card 2 and the information to be recorded are not coincided with each other, the card 2 is collected. Specifically, the feed roller 20 is rotated in the forward direction until the rear end of the card 2 is disposed on the front side with respect to the closing part 23 a and then, the feed roller 20 is rotated in the reverse direction. When the feed roller 20 is rotated in the reverse direction, the pinch roller 21 located at the first facing position “P 1 ” is moved to the second facing position “P 2 ”. In this case, the movement of the pinch roller 21 to the second facing position “P 2 ” is assisted by abutting the rear end of the card 2 with the lower side face of the closing part 23 a.
Further, when the pinch roller 21 is moved to the second facing position “P 2 ”, the card 2 is carried until the front end of the card 2 is passed through between the feed roller 20 and the pinch roller 21 and, when the front end of the card 2 is passed through between the feed roller 20 and the pinch roller 21 , the card 2 is collected in the card collecting part 5 . When the card 2 is collected in the card collecting part 5 , next card 2 is sent out from the card sending-out part 4 . When the feed roller 20 is rotated in the forward direction for sending out the next card 2 , the pinch roller 21 located at the first facing position “P 1 ” is moved to the second facing position “P 2 ”.
As described above, in this embodiment, the feed roller 20 is rotated in the forward direction or the reverse direction based on a reproduced result in the recording and reproducing part 3 . In accordance with an embodiment of the present invention, when a user forgets to take the issued card 2 , the feed roller 20 is rotated in the reverse direction and the card 2 is collected in the card collecting part 5 .
Principal Effects in this Embodiment
As described above, in this embodiment, when the feed roller 20 is rotated in the forward direction, the pinch roller 21 located at the second facing position “P 2 ” is moved to the first facing position “P 1 ” and is held at the first facing position “P 1 ” by the urging force of the torsion coil spring 22 . Further, when the feed roller 20 is rotated in the reverse direction, the pinch roller 21 located at the first facing position “P 1 ” is moved to the second facing position “P 2 ” and is held at the second facing position “P 2 ” by the urging force of the torsion coil spring 22 . Further, in this embodiment, when the pinch roller 21 is moved to the first facing position “P 1 ” or the second facing position “P 2 ”, the feeding direction of a card 2 which is carried by the feed roller 20 and the pinch roller 21 is switched. Therefore, in this embodiment, the feeding direction of a carried card 2 is switched with a simple structure with the use of the torsion coil spring 22 . Further, in this embodiment, the structure of the feeding direction switching mechanism 6 is simplified and thus the structure of the medium issuing and collecting device 1 can be simplified. Therefore, the size of the medium issuing and collecting device 1 can be reduced.
In this embodiment, the third facing position which is the toggle point is located at a substantially middle position between the first facing position “P 1 ” and the second facing position “P 2 ”. Therefore, in comparison with a case that the third facing position is displaced to the first facing position “P 1 ” side or to the second facing position “P 2 ” side, the friction coefficients of the feed roller 20 and the pinch roller 21 , the urging force of the torsion coil spring 22 and the like are easily set for moving the pinch roller 21 from the first facing position “P 1 ” to the third facing position, and the friction coefficients of the feed roller 20 and the pinch roller 21 , the urging force of the torsion coil spring 22 and the like are easily set for moving the pinch roller 21 from the second facing position “P 2 ” to the third facing position. Therefore, in this embodiment, the pinch roller 21 is easily moved between the first facing position “P 1 ” and the second facing position “P 2 ”.
In this embodiment, the flapper 23 performs a function for guiding a card 2 so that the pinch roller 21 is moved to the second facing position “P 2 ”. Therefore, the pinch roller 21 is easily moved from the first facing position “P 1 ” to the second facing position “P 2 ” by utilizing the flapper 23 . Further, in this embodiment, the recessed part 11 b is formed in the frame 11 so as to prevent a card 2 from abutting with the frame 11 when the feed roller 20 is rotated in the reverse direction in a state that a card 2 is sandwiched between the feed roller 20 and the pinch roller 21 and the pinch roller 21 is moved from the first facing position “P 1 ” to the second facing position “P 2 ”. Therefore, the pinch roller 21 is easily moved from the first facing position “P 1 ” to the second facing position “P 2 ”.
In this embodiment, the pinch roller 21 is turned with the rotation center “C 1 ” of the feed roller 20 as a turning center and, when the pinch roller 21 is moved from the first facing position “P 1 ” to the second facing position “P 2 ”, the feeding direction of a card 2 is switched. Further, the flapper 23 is disposed so that, when the pinch roller 21 is moved to the second facing position “P 2 ”, the rear end side of the card 2 does not abut the lower side face of the closing part 23 a . Therefore, when the feeding direction of a card 2 is to be switched and, after the feeding direction of the card 2 is switched, the card 2 sandwiched between the pinch roller 21 and the feed roller 20 is hardly resiliently bent. Accordingly, in this embodiment, damage of an antenna incorporated into a card 2 which is occurred due to a bending stress of the card 2 can be prevented.
In this embodiment, the guide groove 11 a is formed on both end sides of the support shaft 27 . Further, the torsion coil spring 22 is disposed at each of the both end sides of the support shaft 27 . Therefore, the support shaft 27 can be moved in a well balanced manner between the first facing position “P 1 ” and the second facing position “P 2 ” by the guide grooves 11 a and the torsion coil springs 22 which are disposed on the both end sides of the support shaft 27 and thus the support shaft 27 is easily moved.
Other Embodiments
Although the present invention has been shown and described with reference to a specific embodiment, various changes and modifications will be apparent to those skilled in the art from the teachings herein.
In the embodiment described above, the urging member which urges the pinch roller 21 toward the feed roller 20 is a torsion coil spring 22 . However, the present invention is not limited to this embodiment. For example, the urging member which urges the pinch roller 21 toward the feed roller 20 may be a tension coil spring 32 as shown in FIG. 7 . In this case, one end of the tension coil spring 32 is relatively turnably attached to the support shaft 27 and the other end of the tension coil spring 32 is relatively turnably attached to a fixed shaft 33 which is a first holding member that is fixed to the frame 11 on a lower side with respect to the feed roller 20 . Further, the fixed shaft 33 is fixed to the frame 11 so that the center “C 2 ” of the support shaft 27 when the pinch roller 21 is located at a substantially middle position between the first facing position “P 1 ” and the second facing position “P 2 ” is disposed on the straight line “L 1 ”, in other words, at a third facing position “P 3 ”, which is formed by connecting the rotation center “C 1 ” of the feed roller 20 with the center “C 13 ” of the fixed shaft 33 .
Further, the urging member which urges the pinch roller 21 toward the feed roller 20 may be a compression coil spring 42 as shown in FIG. 8 . In this case, one end of the compression coil spring 42 abuts the support shaft 27 and the other end of the compression coil spring 42 is relatively turnably attached to the fixed shaft 43 which is a first holding member fixed to the frame 11 on an upper side with respect to the pinch roller 21 . Further, the fixed shaft 43 is fixed to the frame 11 so that the center “C 2 ” of the support shaft 27 when the pinch roller 21 is located at a substantially middle position between the first facing position “P 1 ” and the second facing position “P 2 ” is disposed on the straight line “L 2 ”, in other words, at a third facing position “P 3 ”, which is formed by connecting the rotation center “C 1 ” of the feed roller 20 with the center “C 23 ” of the fixed shaft 43 . When the urging member is a compression coil spring 42 , a guide part is required for preventing buckling of the compression coil spring 42 .
Further, the urging member which urges the pinch roller 21 toward the feed roller 20 may be another type of spring member or may be an elastic member such as rubber.
In the embodiment described above, the support shaft 27 which supports the pinch roller 21 is held by the frame 11 . However, the present invention is not limited to this embodiment. For example, the support shaft 27 may be held by a lever member which is capable of turning with the rotation center “C 1 ” of the feed roller 20 as a turning center. In this case, for example, the support shaft 27 is fixed to one end side of the lever member and the other end side of the lever member is turnably held by the rotation shaft 24 . In this case, the pinch roller 21 is easily moved between the first facing position “P 1 ” and the second facing position “P 2 ” by utilizing a frictional force between the rotation shaft 24 and the lever member. Further, in this case, a side face of the lever member and a side face of the feed roller 20 may be contacted with each other in a pressed manner. According to this structure, the pinch roller 21 is further easily moved between the first facing position “P 1 ” and the second facing position “P 2 ” by utilizing the frictional force between the side face of the lever member and the side face of the feed roller 20 .
Further, in this case, similarly to the embodiment described above, a turning range of the lever member may be restricted by the support shaft 27 inserted into the guide groove 11 a and the guide groove 11 a so that the lever member is turned between the first facing position “P 1 ” and the second facing position “P 2 ”. Alternatively, a stopper member restricting a turning range of the lever member may be provided so that the lever member is turned between the first facing position “P 1 ” and the second facing position “P 2 ”. Further, in this case, the lever member is a second holding member which holds the support shaft 27 .
In the embodiment described above, the third facing position where the pinch roller 21 and the feed roller 20 are each other is located at a substantially middle position between the first facing position “P 1 ” and the second facing position “P 2 ” so that the rotation center “C 1 ” of the feed roller 20 , the engagement part 22 a and the engagement part 22 b of the torsion coil spring 22 are disposed in a substantially straight line. However, the present invention is not limited to this embodiment. For example, the third facing position may be displaced to the first facing position “P 1 ” side or may be displaced to the second facing position “P 2 ” side.
Further, the third facing position may be coincided with the first facing position “P 1 ” or may be coincided with the second facing position “P 2 ”. When the third facing position is coincided with the first facing position “P 1 ”, the pinch roller 21 is in an unstable state at the first facing position “P 1 ” and may be easily returned to the second facing position “P 2 ”. Further, in a case that the third facing position is coincided with the second facing position “P 2 ”, the pinch roller 21 is in an unstable state at the second facing position “P 2 ” and may be easily returned to the first facing position “P 1 ”. However, also in these cases, when the friction coefficients of the feed roller 20 and the pinch roller 21 , the urging force of the torsion coil spring 22 , the angle “θ” and the like are appropriately set, similarly to the embodiment described above, the feeding direction of a carried card 2 can be switched with a simple structure with the use of the torsion coil spring 22 .
In addition, the fixed shaft 28 may be fixed to the frame 11 so that the straight line “L” connecting the rotation center “C 1 ” of the feed roller 20 with the center “C 3 ” of the fixed shaft 28 is disposed on the clockwise direction side in FIG. 6 with respect to the line connecting the center “C 2 ” of the support shaft 27 with the rotation center “C 1 ” of the feed roller 20 when the pinch roller 21 is located at the first facing position “P 1 ”. In this case, the pinch roller 21 is urged to the second facing position “P 2 ” side by the urging force of the torsion coil spring 22 . Further, in this case, when the feed roller 20 is rotated in the forward direction, the pinch roller 21 located at the second facing position “P 2 ” is moved to the first facing position “P 1 ”. Alternatively, the fixed shaft 28 may be fixed to the frame 11 so that the straight line “L” connecting the rotation center “C 1 ” of the feed roller 20 with the center “C 3 ” of the fixed shaft 28 is disposed on the counterclockwise direction side in FIG. 6 with respect to the line connecting the center “C 2 ” of the support shaft 27 with the rotation center “C 1 ” of the feed roller 20 when the pinch roller 21 is located at the second facing position “P 2 ”. In this case, the pinch roller 21 is urged to the first facing position “P 1 ” side by the urging force of the torsion coil spring 22 . Further, in this case, when the feed roller 20 is rotated in the reverse direction, the pinch roller 21 located at the first facing position “P 1 ” is moved to the second facing position “P 2 ”. Also in these cases, when the friction coefficients of the feed roller 20 and the pinch roller 21 , the urging force of the torsion coil spring 22 , the angle “θ” and the like are appropriately set, similarly to the embodiment described above, the feeding direction of a carried card 2 can be switched with a simple structure with the use of the torsion coil spring 22 .
In the embodiment described above, the feeding direction switching mechanism 6 is provided with the flapper 23 . However, in a case that, when the feed roller 20 is rotated in the reverse direction, the pinch roller 21 is surely moved to the second facing position “P 2 ” so that a card 2 is surely collected in the card collecting part 5 , the feeding direction switching mechanism 6 may be provided with no flapper 23 .
In the embodiment described above, the pinch roller 21 is rotatably supported by the support shaft 27 . However, the present invention is not limited to this embodiment. For example, the pinch roller 21 may be fixed to a rotation shaft rotating together with the pinch roller 21 or the pinch roller 21 may be integrally formed with a rotation shaft rotating together with the pinch roller 21 . In this case, the rotation shaft is a support shaft for rotatably supporting the pinch roller and, for example, a bearing which rotatably supports the rotation shaft is held by the frame 11 . Further, in this case, an end of the torsion coil spring 22 is engaged with the bearing and a guide part for guiding the bearing between the first facing position “P 1 ” and the second facing position “P 2 ” is formed in the frame 11 .
In the embodiment described above, the medium issuing and collecting device 1 collects a card 2 which is sent out from the card sending-out part 4 as needed. However, the present invention is not limited to this embodiment. For example, the medium issuing and collecting device 1 may collect a card 2 which is inserted from the outside as needed. Further, in the embodiment described above, the recording and reproducing part 3 is provided with the antenna 9 for communication. However, the recording and reproducing part 3 may be provided with a magnetic head and/or an IC contact instead of the antenna 9 or in addition to the antenna 9 .
In the embodiment described above, the medium issuing and collecting device 1 having an issuing function and a collecting function of a card 2 is described as an example of a structure of the feeding direction switching mechanism 6 in accordance with an embodiment of the present invention. However, the feeding direction switching mechanism 6 may be utilized in various devices in which switching of the feeding direction of a card 2 is required.
While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention.
The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
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A medium transport direction switching mechanism may be provided of a simple configuration which is capable of switching the transport direction of a transported information recording medium. One end may be a biasing member for biasing a pinch roller toward a transport roller engages a support shaft which supports the pinch roller, whereas the other end of the biasing member engages a retaining member which retains the support shaft. In the medium transport direction switching mechanism, rotational behavior of the pinch roller centering upon a rotational center of the transport roller is possible between a first facing position and a second facing position, wherein the pinch roller moves to the first facing position when the transport roller rotates positively, and moves to the second facing position when the transport roller rotates negatively.
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BACKGROUND AND SUMMARY OF THE INVENTION
The present invention is related to an insulating building block. More particularly, the present invention is related to an insulating building block which is obtained by applying a layer of a foam material to an interior side face of a hollow masonry building block, thus providing a building block having improved energy-saving features.
Previous masonry building blocks having insulating features have included blocks such as those described in U.S. Pat. Nos. 3,704,562 and 3,885,363. These patents are directed to the use of preformed inserts of foam material for building blocks. The use of such inserts has been accompanied by various disadvantages, including the requirement that the insert be formed as a separate unit which must then be inserted into the cavities or hollow portions of the building blocks. Such usage gives rise to various problems, including lack of proper fit of the insert in a particular building block.
By the present invention, there is provided an insulating building block which is a composite of masonry material and a foam material. The insulating building block of the present invention is obtained by applying a layer of foam material to a longitudinally extending side face of each cavity within the hollow block. By the present invention, a block manufacturer is enabled to produce directly at his facility a complete, unitized product having improved energy-saving features over those of the prior art. With the present composite construction, a building wall is properly insulated as soon as the building blocks have been laid. Furthermore, the layer of foam material does not hinder the use of the cavities of the blocks as finger access openings for workmen handling the blocks during construction. In addition, an efficient and economical utilization is made of the foam material to provide a high degree of thermal insulation with a relatively small amount of foam.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the insulating building block of the present invention will be more completely understood from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a perspective view showing a building block and a pair of shield inserts employed in the present invention, one of the shield inserts being disposed within one of the two similar cavities of the block and the second shield insert being arranged above the other cavity for entry into the cavity;
FIG. 2 is a perspective view similar to FIG. 1, showing both shield inserts disposed within respective block cavities and with the foam layer having been applied from the foam dispensing gun; and
FIG. 3 is a vertical cross-section taken along line 3--3 in FIG. 2 but showing the building block with the shield inserts having been removed.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the illustrated embodiment of the present invention as shown in FIGS. 1 through 3, a building block 11 of concrete or the like is employed along with a pair of shield inserts 12, one for each of the two similar cavities 13 shown in the block 11. As shown in FIG. 1, the building block 11 is of a conventional type, having a pair of longitudinally extending side walls 14, 15 which are interconnected by end webs 16, 17 and a transverse intermediate web 18 which separates the cavities 13. Thus the present invention is not intended to be limited to building blocks of any particular configuration or material, the only limitation being that the block have at least one cavity or hollow portion, to the longitudinally extending side face of which the foam material can be applied, as hereinafter described.
In carrying out the method of the present invention for providing an insulating building block, the shield inserts 12 are inserted into the cavities 13 in the block 11, as shown in FIGS. 1 and 2. A release agent is applied to the surfaces of the shield inserts 12 so that foam will not adhere to the shield inserts 12. The release agent may be any of the well-known materials which are used for this purpose, such as silicone, wax or a teflon coating.
In forming the layer of foam, a conventional foam dispensing gun 19 is employed along with a suitable foam source (not shown), with the dispensing gun 19 being aimed at the cavities 20 formed between each shield insert 12 and the block 11. The foam may be a material such as urethane foam or the like which has excellent insulating properties. During application of the foam, the block 11 is preferably placed upon a horizontal supporting surface which will effectively prevent foam from flowing out beneath the cavities 20. As the foam material is sprayed from the dispensing gun 19, the foam will flow into and completely fill the cavities 20 and adhere to the block 11, forming a layer 21 as shown in FIG. 2. For insulating purposes, this layer 21 may have a thickness of from about 1/4 to about 4 inches, with the actual thickness being determined primarily by the requirements of climate conditions, depending upon the geographical location in which the blocks are being used.
In FIG. 3, there is shown the foam insulation layer 21 which remains adhered to the building block 11 after the foam has hardened and the shield inserts 12 have been removed. It is seen that the foam layer 21 covers essentially the entire longitudinally extending, vertical side face 24 of each of the cavities 13.
The shield inserts 12 may be of any construction which will provide a plug for the center portion of each cavity 13 of the block 11. Thus, for example, the inserts 12 may be made of wood strips 22 fastened together and having sheet metal 23 wrapped around and secured thereto. The shield inserts 12 should be of a length sufficient to extend the entire vertical dimension of the block 11 and of a width sufficient to be contiguous with the intermediate web 18 and the respective end web 16 or 17, thus effectively preventing foam from flowing beyond the cavity 20 formed between each shield insert 12 and the interior surfaces of the hollow block 11. The side wall of each shield insert 12 which forms one face of the respective cavity 20 should preferably be substantially vertical, in order that the foam layer 21 which is formed on the vertical side face 24 of each cavity 13 will be of uniform thickness over the entire surface of the side face 24.
The foam material may be advantageously applied to the building block 11 after the block has been preheated or by use of the retaining heat developed during curing of the block.
The application of the foam material to one longitudinally extending side face 24 of each cavity 13 provides the improved insulating features of the present invention. However, it is also within the scope of the present invention to provide a space between the shield insert 12 and its respective cavity 13 extending completely around the four sides of the cavity 13 and to apply a layer of foam in this space so that the layer extends continuously around all sides of the cavities 13.
By the present invention, there is provided an economical and efficient method of preparing an insulating building block for use in the construction industry. In providing the layer of foam on the side faces of cavities located within the block, there is thus presented an effective insulating barrier to the flow of heat through the block, and with the foam barrier being provided as an integral part of a composite, one-piece building block unit.
It is thought that the invention and many of its attendant advantages will be understood from the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the forms hereinbefore described being merely preferred embodiments thereof.
Alternatively, the foam may be applied by spray techniques without the use of the shield insert.
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An insulating building block which is a composite of masonry material and a foam material is disclosed. The building block is obtained by applying a layer of foam material to a longitudinally extending side face of a cavity located within the block. A shield insert may be employed to define that portion of a block cavity which is to receive the foam.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application is a continuation-in-part of and claims priority under 35 U.S.C. § 120 from U.S. patent application Ser. No. 10/010,340, which was filed on Dec. 5, 2001, and under 35 U.S.C. § 119(e) from U.S. Provisional Patent Application Serial No. 60/445,782, which was filed on Feb. 7, 2003. The disclosures of U.S. patent application Ser. Nos. 10/010,340 and 60/445,782 are hereby incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a method for impounding escrow funds from debit/credit card payments made to a merchant. More specifically, the present invention relates to a method for impounding escrow funds from debit/credit card payments made to a merchant, where the impounded escrow funds are determined in relation to at least one of credit, debit and cash sales made by the merchant.
BACKGROUND OF THE INVENTION
[0003] Computers facilitate with high speed and accuracy a vast myriad of commercial transactions—including credit card transactions. Merchants, who collect from their customers not only the retail charges for purchased goods and services but in addition collect customer payments for sales taxes on those purchases, are responsible for periodically transmitting to the appropriate taxing authority the accumulated tax payments received, typically monthly or quarterly for State taxing authorities. At the end of each such period, some merchants find that they have spent or otherwise failed to segregate and retain sufficient funds to make the required tax payment to the taxing authority.
[0004] There is a need to for an improved method by which a merchant may allocate and escrow funds for periodic payment of customer sales taxes owed to a tax authority. Toward this end, it is highly desirable that the improved method enable collection, escrowing and payment to be performed by one or more third parties in order to enable the merchant's direct participation may be limited to a “passive” role. In addition, the method must be capable of generating appropriate payment forms and reports as required by the merchant and the taxing authority.
SUMMARY OF THE INVENTION
[0005] A method is disclosed for impounding escrow funds by an electronic funds processor (EFP) associated with sales transactions of a merchant during a close-out period. The method includes the steps of determining a first sales amount associated with one or more sales transactions of the merchant during the closeout period, determining a second sales amount specifically associated with one or more credit/debit card transactions of the merchant during the closeout period, determining an escrow amount based on the first sales amount, determining whether the second sales amount exceeds the escrow amount, and crediting an escrow account with the escrow amount and a merchant account with an amount equal to the difference between the second sales amount and the escrow amount when the second sales amount exceeds the escrow amount.
[0006] In a preferred embodiment, the method impounds escrow funds for paying a sales tax owing on merchant sales. In this preferred embodiment, the first sales amount is associated with taxable sales transactions including at least one of taxable credit/debit card sales and taxable non-credit/debit card sales, and the second sales amount is associated with taxable and non-taxable credit/debit card transactions of the merchant made during the closeout period. An escrow agent (for example, a third-party bank or other financial institution) periodically makes payments from the escrow account, and provides associated reporting to the merchant and the associated tax authority.
[0007] In this manner, for example, a merchant may provide for ongoing and automatic collection of funds to pay sales taxes by the escrow agent. Similarly, the merchant may provide for periodic, automatic payment of taxes from the collected funds to tax authority. In this manner, the merchant's direct role in such collections effectively becomes passive.
[0008] The method also contemplates other applications in which a merchant desires or is otherwise required to effect a withholding of funds collected from credit-bases sales transactions (for example, by local, state and federal tax authorities, judicial authorities, and payees who have received legal judgments against a merchant). In addition, the method contemplates impounding merchant escrow funds for paying back payroll taxes or back real estate taxes, or for effecting a merchant savings account.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] A more complete understanding of the invention may be obtained by reading the following description of specific illustrative embodiments of the invention in conjunction with the appended drawing in which:
[0010] [0010]FIG. 1 provides a first schematic diagram illustrating elements of the inventive method;
[0011] [0011]FIG. 2 provides a second schematic diagram illustrating elements of the inventive method;
[0012] [0012]FIG. 3 provides a third schematic diagram illustrating a process for obtaining authorization for a credit card sale; and
[0013] [0013]FIGS. 4A-4C illustrate sample escrow transactions involving non-credit/debit card sales.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] The following detailed description includes a description of the best mode or modes of the invention presently contemplated. Such description is not intended to be understood in a limiting sense, but to be an example of the invention presented solely for illustration thereof, and by reference to which in connection with the following description and the accompanying drawing one skilled in the art may be advised of the advantages and construction of the invention.
[0015] Currently, electronic funds processors (EFPs) are commonly used in the industry for managing credit and debit card transactions between merchants and banks. This function often includes the collection of associated service fees by the EFP on behalf of the credit/debit card provider (for example, Visa/MC, Discover, and Diner's Club) for electronic funds transfer (EFT) to a merchant account. Alternatively, in the case of American Express (AMEX), service fees are first deducted before net sales (less service fees) are EFT deposited by AMEX in the merchant account.
[0016] In accordance with the present invention, a selective escrow method is disclosed in which a third party (the EFP) collects merchant funds to be escrowed for payment of customer sales tax. The method can be described as follows.
[0017] Initially, information entered at a credit card/debit terminal (for example, entry of the credit/debit card number by swiping, and purchase amount and card expiration by keypad entry) is received by the EFP and forwarded to a credit/debit card issuer for authorization. Authorization is provided (for example, as indicated by an issuer-assigned confirmation number) and forwarded by the provider via the EFP to the merchant for storage in the credit card terminal. Currently, there are a number of manufacturers (for example, HYPERCOM, TRANS330, and NCR) making credit/debit card terminals (for example, MAC, NYCE, and check debit card) for use on the merchant level.
[0018] At the end of a transaction period (for example, at the end of each day), the merchant “closes out” credit/debit card sales at a credit card terminal, thereby requesting to the EFP that payments reflecting the daily sales be made to the merchant's account.
[0019] Once the EFP has obtained the request funds from the credit/debit card issuers, customer sales tax owing is debited from the gross taxable sales, and the net funds are sent on via EFT to the merchant's account or to another provider (such as American Express) for delivery to the merchant's account. The debited tax portion is credited to an escrow account for making future tax payments.
[0020] Because sales tax owed can be readily determined from the number, nature and place of merchant sales, the EFP can be provided with instructions to readily and automatically facilitate the escrow process in order to relieve the merchant from having to deal with holding funds aside and otherwise manage the process of making sales tax payments. Software currently used by the EFP to manage the credit/debit card issuer fee debiting process can be readily adapted to carry out the merchant instructions.
[0021] Once deposited in the escrow account, funds may be transferred at defined schedules to state tax authorities (or other owed parties) by the escrow agent in order to meet the merchant's tax payment obligations. In consideration for performing this service, the escrow agent may be reimbursed, for example, by retaining interest earned on funds (“float”) in the account in between payment periods.
[0022] As previously noted, the method may be easily incorporated in the software the EFP currently uses, for example, to deduct the credit/debit card provider fees charged to the merchant for account transactions. FIG. 3 illustrates this present process. Credit/debit card providers charge whatever is a competitive rate to get a merchants business, and usually take their fees at the end of the month based on the merchant's gross sales. American Express takes its fees following each batch of transactions of recent transactions submitted by the merchant.
[0023] Accordingly, the present invention provides a method by which sales tax for customer sales transactions can be directly debited by an EFP from credit/debit card transactions, escrowed by a third party (for example, a major bank or other financial institution) and paid to the tax authority, all with little or no imposition of burden on the merchant. This method can be easily implemented, as the EFP is already processing credit/debit transactions in order to credit the gross amount of a credit card transaction, less the bank provider's fees, to the merchant's bank account. The method can also easily account for and discount sales transactions that are exempted from paying customer sales tax, so that no debit and escrow of such sums occurs from such transactions.
[0024] Customer sales tax owed for cash transactions (for example, payments made with physical currency, checks or other foreseeable items of monetary value) can also be accommodated by the present method. A number of approaches for escrowing customer sales tax accruing from cash transactions are contemplated by the present invention, and are disclosed as follows.
[0025] In a first approach, at the end of the day after closing out his/her credit card terminal and sending the transaction via EFT to EFT, the merchant “swipes” a card which can be called a “cash transaction tax debit” card or CTTD card, through his/her credit card terminal. This CTTD card may be be provided, for example, by a banking institution of the merchant for the purpose of facilitating debiting of the taxable portion of cash sales from the merchant's account at the banking institution for credit to the escrow account. As an alternative to using the CTTD card, the merchant may enter a banking institution provided personal identification number (PIN), or the credit/debit card terminal provide may provide a special function button on the terminal for this purpose. The special function button would allow the merchant to enter the total of his or her cash transactions, either daily or monthly or other selectable period, and transmit this information to the EFP.
[0026] A taxable portion of the reported cash transactions would be calculated by the EFP, debited from the merchant's account and credited to the escrow account. Of course, the merchant may prefer to perform the cash transaction closing process at a variety of intervals (for example, once monthly) instead of daily.
[0027] An alternative approach for collecting cash transaction sales tax, which may be preferred, is further described herein. As described previously, a merchant may be provided with either one of a swipe card or a PIN for processing cash transactions from the merchant's terminal when doing a close out. Both approaches allow the merchant to make what is referred to as a “forced entry” for the cash sales when closing out their terminal.
[0028] The forced entry provides information to the EFP indicating the total cash sales and how much sales tax to debit. Sales tax for cash sales could be escrowed, for example, by debiting it from the merchant's business checking account. For example, if sales tax is 6% and cash sales are $100, $6.00 would be debited from the merchant's checking account and credited to the tax escrow account along with the sales tax debited from credit card sales. The merchant would retain the cash from the cash sales and deposit it into his business checking account.
[0029] As an alternative, the “forced entry” may be eliminated by a method of tax debiting in which the reporting of cash and non taxable sales is integrated into the terminal closeout process.
[0030] Instead of a forced entry for the cash and non taxable sales, the credit/debit card terminal is configured to collect and report three sales transaction totals associated with a closeout period: one for credit card sales, one for cash sales and one for non taxable sales. This may be accomplished, for example, by suitable programming of the terminal (conventional terminals, for example, have been programmed to ask operators to report whether a transaction is taxable or non taxable) For each tax jurisdiction, the merchant's terminal is programmed to add the credit card and cash sales, subtract the non taxable sales, and calculate the percentage of tax to be escrowed based on the tax jurisdiction. The percentage of tax from the combined credit card and cash sales is then debited from authorized credit card funds, and deposited into the tax escrow account. The merchant retains all funds received from cash sales (and for example, may deposit these in the merchant bank account).
[0031] Three examples illustrating escrow transactions at the merchant terminal are illustrated in FIGS. 4A-4C. In FIG. 4A, all reported sales transaction in the closeout period are credit sales, each owing a 6% tax in a tax jurisdiction. Total sales tax escrow is computer based on the tax rate and total credit card sales, a net credit card deposit (less escrowed tax funds) is deposited in the merchant account.
[0032] In FIG. 4B, total credit and total cash sales are each reported for a closeout period, each owing a 6% tax in a tax jurisdiction. Credit and cash sales are totaled, and a total sales tax escrow is computed based on the tax rate and on total sales. A net credit card deposit (less escrowed tax funds representing tax owed both on credit and cash sales) is deposited in the merchant account.
[0033] In FIG. 4C, both taxable and non-taxable credit and cash sales totals are reported. For example, state laws may characterize certain sales as non-taxable (for example, clothes purchases in New Jersey are generally non-taxable). Each taxable sale owes a 6% tax in a tax jurisdiction. Taxable and non-taxable totals are prepared for both total credit and total cash sales during the closeout period, and a total sales tax escrow is computed based on the tax rate and on total taxable credit and cash sales. For example, all cash and credit sales may be totaled, and non-taxable cash sales and non-taxable credit sales may be subtracted from total cash and credit sales to produce total taxable sales. The tax rate is then applied to total taxable sales to determine the tax escrow. A net credit card deposit (total credit card sales less tax escrow and any other applicable service fees) is deposited in the merchant account. All cash collected remains in hand with the merchant.
[0034] In addition to escrowing funds for sale tax owed on cash sales, the above-disclosed method may be extended, for example, to sales made via mail/phone/fax orders and Internet sales.
[0035] In order to extend the method accordingly, mail/phone/fax sales and Internet sales may be identified with tax codes for taxable and non taxable sales. Currently, these sales may only be taxable if you are ordering from the same state in which the merchant is based, or alternatively if the merchant you are ordering from has a retail outlet in your state. The associated rules tend to be reasonably straight forward, and accordingly easily incorporated for example in existing software that the merchant may be using to track orders and delivery for such sales. Such merchant sales information could be reported to the EFP and escrow agent via an interface from the tracking software to the merchant terminal, or alternatively by other automated communications means (for example, e-commerce). An interface to the merchant terminal provides an advantage of enabling the merchant to close out these transactions coincidentally with closing other transactions recorded at the terminal.
[0036] As sales tax collected from mail/phone/fax order and Internet sales will generally be based on the tax jurisdiction in which the sale is initiated, a merchant must collect applicable sales tax based on the tax jurisdiction of where the sale is initiated, and file that tax in accordance with that jurisdiction's tax laws. Accordingly, each taxable sale would additionally identify the associated tax jurisdiction. Once again, the jurisdiction may be easily determined from a customer's order information, and means for determining the jurisdiction thereby easily incorporate in the merchant's existing order and delivery tracking software.
[0037] As a result, such information may be collected and provided to the escrow agent so that sales tax owed from mail/phone/fax sales and Internet sales within a closeout period can be escrowed out of credit sales receipts closed during the period, and sales tax filings and payments for mail/phone/fax and Internet order sales may automatically be filed on behalf of the merchant by the escrow agent on a schedule and as required by each of multiple jurisdictions. In addition to escrowing sales tax from credit or debit card orders for mail/phone/fax and Internet sales, by using the method described above for cash receipts, sales tax may also be escrowed for orders made for example using a personal check, money order, bank check, travelers check, gift check, gift certificate, cash or any other financial instrument used as cash. Future tax liabilities (for example, for Internet sales initiated outside of a merchant jurisdiction) may be easily accommodated by the method and reflected in modifications to the merchant's order and delivery tracking software.
[0038] As is described further herein, the present method may also be used for collecting other taxes, liens, garnishments and levies that may be imposed on a merchant by state and/or federal government agencies. For example, the method may provide for adjusting the rate of sales tax collection in order to address back taxes. In this manner, a merchant may for example reimburse a state sales tax authority for back taxes owed at a manageable rate, until the back taxes are repaid. For example, in a case where taxable sales receipts are taxed at a rate of 6%, the escrow rate may be adjusted upward (for example, to 16%) in order to collect against back sales tax owing. In the present provisional patent application, it is contemplated that the method could be applied to virtually any application in which a merchant desires or is otherwise required to effect a withholding of funds collected from credit-bases sales transactions, and for payment of escrowed merchant funds to any legitimate payee (for example, local, state and federal tax authorities, judicial authorities, and payees who have received legal judgments against a merchant). For example, in addition to the applications previously disclosed, it is contemplated that the method could be applied to generate merchant escrow funds for paying back payroll taxes or back real estate taxes, or for effecting a merchant savings account (in the latter case, the payee of funds escrowed would be the merchant).
[0039] It is also contemplated that the present method may be used for the purpose of creating multiple escrow funds simultaneously. For example, the merchant could specify more than one escrow rate each to be applied to one or more classes of eligible sales transactions. Preferably, the merchant terminal would be programmed for entry of such rates, and for reporting of the rates and associated merchant and transaction information to the EFP and escrow agent. The reported information would preferably and as applicable identify authorities and/or parties to whom associated escrowed funds would be disbursed at specified rates and schedules, and include conventional secure means for the merchant to authorize these transactions to begin and/or to end (for example, by digital signature). Optionally, for example for payments associated with legal judgments, such secure authorization means may be extended to other parties.
[0040] An important function of the present invention is to provide information about escrowed funds to the merchant, and to each tax jurisdiction in which sales tax receipts are being filed. As described herein, escrow account information can be provided at the merchant terminal at the time of a close out in a form, for example, similar to the sales draft created by the terminal in response to each sales transaction. In addition, the present method contemplates escrow account management software periodically used by the escrow agent, for example, to report a monthly summary to the merchant, and/or to prepare a filing return for filing tax receipts in a tax jurisdiction. If one or more types of funds are being escrowed, the monthly summary to the merchant may for example report the following information for each type: a) escrow funds collected over a current closeout period, and cumulatively for a designated number of prior closeout periods, b) escrow funds paid for a current payment period and cumulatively for a designated number of prior payment periods, and c) balance of funds owed (if the fund type relates, for example, to back taxes or other obligations not relieved in a single payment period).
[0041] The escrow agent may for example provide a secure web site for presenting escrow account information to the merchant and/or other payees (for example, the tax authorities). Alternatively, the escrow agent may physically or electronically transmit (for example, by e-mail, facsimile or other e-commerce means) escrow account information on a periodic basis directly to the merchant and/or payee.
[0042] Additional applications of the method beyond state sales tax collection for account transactions include any and all taxes which can be paid or charged at a point of sale (for example, Value Added Tax or VAT).
[0043] Summarizing, it is an achievement of the disclosed system and method that only the charges for goods/services and not the separate tax portion are transferred to the merchant's account-and the appropriate tax amount is transferred to an escrow account held by the bank who has the transfer relationship with the business owner. This escrow amount would be paid monthly or quarterly, for example to the state where the business transaction took place easily, speedily and accurately.
[0044] EFT systems are well known architecture. The software logic for deducting a certain percent of gross sales is also known as banks utilize it to take their fees. A system for filing tax money with a state is also known since banks regularly make tax payments for corporate clients. Yet none of the these systems presently offer advantages described in conjunction with the disclosed method.
[0045] Many present EFT systems provide effective security, for example such as encryption, as for moving money between accounts. The disclosed method contemplates a secure web based account available to the merchant that enables the merchant to check the status of their account with the escrow agent. In addition, as an alternative to cash transaction reporting, a web-based account may be provided to allow communications between the EFP and the merchant with regard to cash transactions.
[0046] The disclosed method may be used to exempt purchases made outside of a prescribed jurisdictional tax base. Alternatively, The method may be applied for multiple jurisdictions, for example, on a state-by-state level and/or national level. The method may also be applied to extract a service fee applied by the EFP.
[0047] The system and method can be customized to address any tax collection that involves tax liens and levies used by the State and Federal Government to collect back taxes from businesses. For example, many small and large businesses fall behind on taxes for any number of reasons and paying back taxes becomes very difficult and expensive for merchants because of penalties and interest and because businesses rarely have large chunks of excess funds to pay back taxes. The collection of back taxes by State and Federal Governments is also a difficult and expensive job because it involves manpower.
[0048] The disclosed method can be utilized by a state or federal government to levy a business for back taxes. For example, suppose a business owes back sales tax to the state. The state sales tax is 6%, but the state would levy the account 16% each month and collect an additional 10% towards back taxes until the debt was paid. In this case, the EFP and escrow agent would employ the disclosed method to act as the collection agents for the state or federal government, thereby cutting the state's collection costs and allowing the merchants to continue operating without extreme economic harm to their business. The method may also be used by collection companies to collect monies toward judgments won against businesses.
[0049] The disclosed system and method may be applied broadly in e-commerce. For example, sales tax may be charged on all e-commerce sales, to be collected in the state in which a sale takes place, analogous to catalog sales today. As the majority of e-commerce sales and catalog sales are credit card transactions, the method provides an sound basis for impounding escrow funds from e-commerce sales.
[0050] The disclosed method may also be used by small businesses to provide a forced savings plan. Many small businesses are S corporations with profits flowing through to the officers as income. To boost this income the EFP could offer to provide an additional debit to be moved into a savings account for the corporation. Many small businesses lack the discipline to save small amounts of money over time, a proven method of saving money. If the EFP offered the disclosed service to deduct an allocatable percentage from each transaction and funnel it, for example, into a bank-managed savings account digitally for the business, a whole new avenue of income is provided for the bank.
[0051] A schematic diagram is provided in FIG. 1 illustrating elements of the method, which are described as follows:
[0052] 1. The customer making a purchases presents a credit or debit card at the point of sale.
[0053] 2. The merchant uses an electronic terminal or the telephone for example, to request an authorization from the credit/debit card provider/issuer via the EFP (depicted in FIG. 1 as a “merchant bank”).
[0054] 3. The merchant bank issues a payment authorization and request message to the card issuer that includes details about the account and the transaction, including escrow account transaction signals. This message may also be forwarded to the escrow agent.
[0055] 4. The credit/debit card issuer reviews the authorizationrequest, makes a decision to approve or decline it, and replies to the EFP. The issuer may also forward the reply to the escrow agent.
[0056] 5. The EFP forwards the issuer's reply to the merchant. The response can also include information to decline, approve, and push escrow account information to the escrow agent.
[0057] It is foreseeable that in some cases, when a credit/debit card issuer is unavailable for authorization, the EFP may authorize the escrow account transaction as a part of a stand-in processing service.
[0058] The method may also be utilized by Independent Sales Organizations or ISOs. Independent sales organizations play a role in many business fields. In the credit card industry, ISOs act as a third party between the merchant and the acquiring bank. Many businesses are unable to obtain merchant status through an acquiring bank because the bank views them as too large a risk, and need to go through an ISO to obtain merchant status. Merchant status is activated when a business has authorization from an acquiring bank, ISO, or other financial institution to accept credit cards. Such status is required in order for the merchant to practice the disclosed method.
[0059] A variety of service providers may be selected to serve in the roles of EFP and escrow agent (for example, First Data, Telecheck, and Paymentech). In addition, a variety of credit card processing services such as EMS Nationwide, First of Omaha, First USA, Paymentech, First Union—Merchant Sales and Services, Nova Information Systems, Vantage Services, MasterCard, American Express, Discover, Worldwide, Citibank, First USA/BANK ONE, MBNA, Discover, J. P. Morgan Chase, Bank of America, Capital One, Household Bank, Providian, and Fleet may also serve in one or more of these roles.
[0060] [0060]FIG. 2 provides another view of the disclosed method.
[0061] A credit and data feed as shown in box 1 interlinks with a bank network (EFP) as shown in box 2 . Charges are received by the EFP as shown in box 3 . The EFP debits a fee percentage, and remits the balance to the merchant's bank account, as shown in box 4 . At the same time, the EFP debits an allocated tax amount for a retailer's gross credit card receipt, and makes an escrow account deposit to the escrow account as shown in box 5 .
[0062] The EFP and/or escrow agent may, for example, use several pricing models to derive revenues from the escrow account services and functionality provided. A first approach is for the EFP and/or escrow agent to charge based on a percentage figure of the overall value of escrow account transactions. A second method is to charge a flat fee for every escrow account transaction regardless of dollar amount. A third approach is for the PSP to charge a transactional fee based upon the volume of escrow account transactions processed.
[0063] The foregoing describes the invention in terms of embodiments foreseen by the inventor for which an enabling description was available, notwithstanding that insubstantial modifications of the invention, not presently foreseen, may nonetheless represent equivalents thereto.
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A method is employed to impound funds from merchant sales electronically in an escrow account for later use such as payment of associated sales taxes. An electronic funds processor (EFP) determines escrow information for credit/debit card charge payment requests made by the merchant via a credit/debit card terminal, forwards the requests to one or more credit/debit card issuers, extracts an escrow amount from payments made by the issuers to the merchant, and credits an escrow account of the merchant with the extracted amounts. An escrow agent periodically makes payments from the escrow account, and provides associated reporting to the merchant. The merchant is able to report cash sales via the credit/debit card terminal, and associated escrow amounts are extracted from credit/debit card payments or from another merchant account.
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RELATED APPLICATION
[0001] This application claims the benefit of priority of U.S. Provisional Application 60/658,765, filed Mar. 5, 2005, the entire contents of which are incorporated herein.
FIELD OF THE INVENTION
[0002] This invention relates generally to a surgical instrument, and, more specifically, to a safety shielded trocar having a V-shaped incision blade.
BACKGROUND
[0003] In laparoscopic surgery, a surgeon guides cameras and long, thin instruments through small incisions in the body. As laparoscopy is less invasive than conventional surgery, laparoscopic techniques typically result in quicker, less painful operations, with less scarring and shorter recovery times. Today, examples of laparoscopic procedures abound. They include tubal ligations, hysterectomies, surgery for endometriosis or other common gynecological problems, gall bladder surgery, and some hernia and heart operations.
[0004] A surgeon typically starts a laparoscopic operation by injecting carbon dioxide gas into a patient's abdomen through a thin needle to create more space between the abdominal wall and the organs. Then, the surgeon makes a piercing incision, using a razor-sharp instrument called a trocar. A conventional trocar is essentially a metal spike contained within a spring-loaded safety sheath. The tip of the trocar is typically needle-like with a beveled piercing tip having sharp edges. The spring-loaded safety sheath is a retractable sleeve positioned around the trocar. The sheath slides back upon contact with the outer surface and walls of the body cavity to reveal a sharp incision edge. After the internal cavity has been breached, the sheath springs forward to cover the sharp incision edge.
[0005] Another style of trocar features a sharp tubular needle with an internal blunt spring-biased obturator. The obturator retracts into the body of the needle during piercing and blocks the interior of the needle to prevent tissue from entering. When the tip of the trocar enters the insufflated cavity, the biasing spring pushes the obturator forward past the sharp tip of the sleeve to prevent accidental puncturing or cutting of internal organs.
[0006] To make an incision with a trocar, a surgeon pushes a trocar through a sealable cannula, skin, fat and connective tissue and into the abdominal cavity. Since the surgeon has not yet inserted a camera, the surgeon cannot see the sharp trocar as it penetrates the body cavity, which may lead to serious collateral injuries. Once the trocar is inserted, the protective spring-loaded sheath should spring forward, covering the blade and protecting arteries and organs. However, the sheath (or obturator) may not always deploy fast enough due to interfering tissue or other mechanical interference. The sheath (or obturator) may also become caught (or plugged up) on tissue and fail to deploy. Additionally, if a surgeon pushes too hard, the force may break the spring. While some manufacturer's labels may warn against pushing too hard, there is no way of gauging how hard is too hard. Compounding these problems, is the fact that safety-shielded trocars might actually lead to accidents because they give surgeons a false sense of security, encouraging them to use more force.
[0007] The only indication of penetration provided by a standard trocar is a reduction in the amount of resistance felt by the surgeon. Consequently, it can be extremely difficult for a surgeon to ascertain when the internal cavity wall has been breached. To address this problem, visible and audible signaling devices have been developed to provide a positive signal when a cavity wall has been breached. However, if the signal is missed or the surgeon fails to react in time, the result can be serious collateral damage.
[0008] After the trocar has been driven into the body cavity, the surgeon may withdraw it and proceed with the laporascopic procedure. The result, when no blood vessels or organs are cut, is quick and easy access to the abdomen. Upon withdrawal of the trocar, a cannula is left in place to provide a sealable access conduit to the insufflated body cavity.
[0009] Another problem with conventional trocars concerns the shape of the cutting blade. Straight line incisions have a tendency to tear and result in greater trauma to neighboring areas, especially upon insertion of a laparoscopic instrument. T-shaped and Y-shaped cutting blades require greater force to pierce the cavity, thereby producing more trauma and scarring.
[0010] Other problems with such trocar assemblies include the capture of tissue intermediate the obturator and the piercing sleeve wall when the obturator is retracted or pushed back by the body cavity wall. Since the tip is beveled, the initial piercing and cutting is performed by the leading edge of the blade formed on the beveled edge of the piercing sleeve. An opening at the trailing edge of the beveled tip is not as smoothly formed as the initial cut, and retraction of the obturator can capture tissue intermediate the obturator and sleeve.
[0011] Although attempts have been made to provide a trocar which facilitates penetration, minimizes tearing and trauma, reliably guards against collateral damage upon insertion and provides a clear positive penetration signal, known trocars provided to date have failed to address this full range of surgeons' needs.
[0012] The invention is directed to fulfilling one or more of the needs and overcoming one or more of the problems as set forth above.
SUMMARY OF THE INVENTION
[0013] To overcome one or more of the problems as set forth above, in one aspect of the invention, a surgical instrument comprised of an incision blade/safety shield cartridge assembly is provided. The incision blade/safety shield cartridge assembly is comprised of a nose cone having an aperture, a stationary V-shaped incision blade having a distal end extending from said aperture, a spring-biased V-shaped safety shield movable from an extended position extending beyond the distal end of said stationary V-shaped incision blade to a retracted position revealing the distal end of said stationary V-shaped incision blade. The V-shaped safety shield has a distal end and a proximal end. A spring is adapted to bias the spring-biased V-shaped safety shield. A safety shield spring retainer housing is operably coupled to the nose cone and configured to support the spring against the proximal end of the spring-biased V-shaped safety shield.
[0014] In an exemplary embodiment, the spring-biased V-shaped safety shield includes a travel stop, and the safety shield spring retainer housing includes a stop lug. The stop lug is adapted to define an abutment for the travel stop when the spring-biased V-shaped safety shield is biased to the extended position. The travel stop and stop lug may also be adapted to produce a sensible signal when the spring-biased V-shaped safety shield is biased to the extended position. The sensible signal may include tactile, audible and visible signals.
[0015] A surgical instrument according to an exemplary embodiment is also comprised of, a sleeve body having a distal end and an opposite proximal end, and a handle. The incision blade/safety shield cartridge assembly is coupled to the sleeve body at the distal end, the handle is coupled to the sleeve body at the proximal end.
[0016] Thus, in one embodiment, an incision blade/safety shield cartridge assembly according to principles of the invention includes a nose cone having an aperture, a stationary V-shaped incision blade having a distal end extending from the aperture, and a spring-biased V-shaped safety shield conformed to the shape of the stationary V-shaped incision blade and movable from an extended position extending beyond the distal end of the stationary V-shaped incision blade to a retracted position revealing the distal end of the stationary V-shaped incision blade. The V-shaped safety shield has a distal end and a proximal end. A spring is adapted to bias the spring-biased V-shaped safety shield. A safety shield spring retainer housing is operably coupled to the nose cone and configured to support the spring against the proximal end of the spring-biased V-shaped safety shield. The spring-biased V-shaped safety shield may include a travel stop and the safety shield spring retainer housing may include a stop lug adapted to define an abutment for the travel stop when the spring-biased V-shaped safety shield is biased to the extended position. Additionally, the travel stop and stop lug may be adapted to produce a sensible signal when the spring-biased V-shaped safety shield is biased to the extended position. The sensible signal may include a tactile signal, an audible signal or a visible signal. The nose cone may includes a biocompatible lubricated surface treatment. The V-shaped incision blade is adapted with a pointed double-beveled edge at its distal end to produce a clean v-shaped incision in a body cavity. In operation, the V-shaped safety shield retracts to the retracted position during piercing of a body cavity and rapidly extends to the extended position upon penetration of a body cavity.
[0017] In another embodiment, a surgical instrument according to principles of the invention includes an incision blade/safety shield cartridge assembly, a sleeve body having a distal end and an opposite proximal end, and a handle. The incision blade/safety shield cartridge is coupled to the sleeve body at the distal end. The handle is coupled to the sleeve body at the proximal end. The incision blade/safety shield cartridge assembly is comprised of a nose cone having an aperture, a stationary V-shaped incision blade having a distal end extending from the aperture, a spring-biased V-shaped safety shield conformed to the shape of the stationary V-shaped incision blade and movable from an extended position extending beyond the distal end of the stationary V-shaped incision blade to a retracted position revealing the distal end of the stationary V-shaped incision blade. The V-shaped safety shield has a distal end and a proximal end, a spring adapted to bias the spring-biased V-shaped safety shield, and a safety shield spring retainer housing operably coupled to the nose cone and configured to support the spring against the proximal end of the spring-biased V-shaped safety shield. The handle has a mushroom shape.
[0018] The nose cone includes a biocompatible lubricated surface treatment. The V-shaped incision blade includes a pointed double-beveled edge at its distal end adapted to produce a clean v-shaped incision. The V-shaped safety shield is adapted to retract to the retracted position during piercing of a body cavity and rapidly extend to the extended position upon penetration of a body cavity. Upon such extension, the safety shield produces a sensible tactile, audible and/or visible signal.
[0019] In yet another embodiment, a surgical instrument according to principles of the invention includes an incision blade/safety shield cartridge assembly, a sleeve body having a distal end and an opposite proximal end, and a handle. The incision blade/safety shield cartridge assembly is coupled to the sleeve body at the distal end. The handle is coupled to the sleeve body at the proximal end. The incision blade/safety shield cartridge assembly is comprised of a nose cone having an aperture, a stationary incision blade with a distal end extending from the aperture, a spring-biased safety shield conformed to the shape of the stationary incision blade and movable from an extended position extending beyond the distal end of the stationary incision blade to a retracted position revealing the distal end of the stationary incision blade. The safety shield has a distal end and a proximal end, a spring adapted to bias the spring-biased safety shield, and a safety shield spring retainer housing operably coupled to the nose cone and configured to support the spring against the proximal end of the spring-biased safety shield. The safety shield is adapted to retract to the retracted position during piercing of a body cavity and rapidly extend to the extended position upon penetration of a body cavity and produce a sensible signal such as a tactile signal, an audible signal and/or a visible signal. The incision blade includes a pointed double-beveled edge at its distal end is adapted to produce a clean incision with a flap.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The foregoing and other aspects, objects, features and advantages of the invention will become better understood with reference to the following description, appended claims, and accompanying drawings, where:
[0021] FIG. 1 illustrates an exterior view of an exemplary trocar according to principles of the invention;
[0022] FIG. 2 illustrates an exterior view of an exemplary trocar according to principles of the invention with a sleeve adapter at the distal end;
[0023] FIG. 2A illustrates an exterior view of an exemplary sleeve adapter according to principles of the invention;
[0024] FIG. 3 illustrates a section view of an exemplary trocar according to principles of the invention;
[0025] FIG. 4 illustrates an exploded top view of an exemplary trocar according to principles of the invention;
[0026] FIG. 5 illustrates an exploded 1 80 degree bottom view of an exemplary trocar according to principles of the invention;
[0027] FIG. 6 illustrates a section view of an exemplary safety-shield cartridge assembly with an incision blade in shielded position for a trocar according to principles of the invention;
[0028] FIG. 6A illustrates a top solid view of an exemplary safety-shield cartridge assembly with an incision blade in shielded position for a trocar according to principles of the invention;
[0029] FIG. 6B illustrates a bottom solid view of an exemplary safety-shield cartridge assembly with an incision blade in shielded position for a trocar according to principles of the invention;
[0030] FIG. 6C illustrates an piercing end view of an exemplary safety-shield cartridge assembly with an incision blade in shielded position for a trocar according to principles of the invention;
[0031] FIG. 7 illustrates a section view of an exemplary safety-shield cartridge assembly with an incision blade in exposed position for a trocar according to principles of the invention;
[0032] FIG. 7A illustrates a solid top view of an exemplary safety-shield cartridge assembly with an incision blade in exposed position for a trocar according to principles of the invention;
[0033] FIG. 7B illustrates a solid bottom view of an exemplary safety-shield cartridge assembly with an incision blade in exposed position for a trocar according to principles of the invention; and
[0034] FIG. 8 illustrates an exemplary safety-shielded trocar installed into an exemplary cannula with a seal cap assembly for piercing a body cavity wall according to principles of the invention; and
[0035] FIG. 9 illustrates a side perspective view of an exemplary v-shaped incision blade and a correspondingly shaped retractable safety shield for piercing a body cavity wall according to principles of the invention; and
[0036] FIG. 10 illustrates a side perspective view of an exemplary v-shaped incision blade and a correspondingly shaped retractable safety shield for piercing a body cavity wall according to principles of the invention; and
[0037] FIG. 11 illustrates a tip-end plan view of an exemplary retractable safety shield according to principles of the invention; and
[0038] FIG. 12 illustrates a tip-end plan view of an exemplary v-shaped incision blade for piercing a body cavity wall according to principles of the invention.
[0039] Those skilled in the art will appreciate that the invention is not limited to the exemplary embodiments depicted in the figures or the shapes, relative sizes, proportions or materials shown in the figures.
DETAILED DESCRIPTION
[0040] With reference to the drawings, wherein like numerals represent like features, an exemplary trocar and components thereof according to principles of the invention are shown in FIGS. 1 through 12 . The invention provides an improved trocar for safely creating an incision in a patient (either human or animal) and establishing an orifice for laparoscopic medical procedures.
[0041] Referring now to FIG. 1 , an exterior perspective view of exemplary embodiment of a trocar according to principles of the invention is illustrated. As shown, the trocar includes a handle 1 , a sleeve body 2 , a staking detail 3 , a nose cone 4 , an incision blade 5 and a retractable safety shield 6 . The incision blade 5 , retractable safety shield 6 , and other components(as discussed below) are housed or partially housed within the nose cone 4 and sleeve body 2 . An incision blade/safety shield cartridge assembly (discussed below) is fixed at the distal end using the indented staking detail 3 . The nose cone 4 includes an aperture for passage of the sharpened distal end of the incision blade 5 and safety shield 6 . The nose cone 4 and handle 1 are attached to the sleeve body 2 in any conventional manner, such as by bonding or mechanical connection. For surgeon comfort and control, the handle 1 preferably has a mushroom shape, though other shapes may be used.
[0042] Optionally, a sleeve adapter 7 is provided, as shown in FIG. 2 . The sleeve adapter 7 may be attached (e.g., bonded) as a collar onto the sleeve tube/body member 2 for the purpose of increasing the effective outer diameter of the sleeve tube/body member 2 . Illustratively, the sleeve adapter 7 may be configured to increase the effective outer diameter of the sleeve tube/body member 2 from 10 mm diameter to 12 mm diameter for use in a cannula with a 12 mm inner diameter. By way of example and not limitation, the sleeve adapter 7 may be comprised plastic of polyethylene, polycarbonate, ABS or other plastic resin.
[0043] Now turning to FIG. 2A , the exemplary sleeve adapter 7 includes a conical taper 7 A at the distal end to continue the conical taper of the nose cone 4 for smooth and gradual incision dilation. A conical taper 7 B is also provided at the proximal end to facilitate removal of the trocar from a cannula after the puncturing. The conical taper 7 B at the proximal end also reduces the possibility of rupturing the rubber gas seal typically contained within a cannula. A glue injection port 7 C is provided for injecting glue utilizing a mating glue injection needle (not shown) to bond the sleeve adapter 7 into a predetermined fixed position onto the sleeve tube/body member 2 . Internal standing ribs 7 D of a determined number and height may also be provided to assure good distribution and adequate glue film thickness between the sleeve adapter 7 and the sleeve tube/body member 2 . Detents 7 E may be provided to facilitate ejection of the part from the plastic injection mold.
[0044] With reference to FIG. 3A , an exemplary trocar according to the present invention includes a substantially hollow sleeve tube/body member 2 with an interior cavity 13 and a tubular wall. The distal end of hollow sleeve tube/body member 2 engages an incision blade/safety shield cartridge assembly 8 . By way of example and not limitation, the sleeve tube/body member 2 is made from thin wall stainless steel tubing of polished or mat finish, or of polycarbonate, ABS or other plastic resin, or any other material suitable for surgical applications.
[0045] The distal end, receives the incision blade/safety shield cartridge assembly 8 to a determined depth. The cartridge 8 may be fixed at the distal end with one or more attachments, such as a “V” shaped indented staking detail 3 , as shown in FIG. 1 . The “V” shaped indented staking detail 3 is used for fixed retention of the internal incision blade/safety-shield cartridge assembly. One or a plurality of spaced apart staking details 3 may be provided to secure the cartridge to the sleeve tube/body member 2 .
[0046] The handle 1 may be fixed by bonding or mechanical attachment onto the proximal end of the sleeve tube/body member 2 . An open chamber or bore 12 in the handle 1 receives a portion of the proximal end of the sleeve tube/body member 2 . The handle 1 may be attached to the proximal end of the sleeve tube/body member 2 by bonding or other suitable fastening means.
[0047] As illustrated in FIGS. 3 , the bore 12 of the handle incorporates a standing tube stop lug 9 near the bottom of the bore 12 of about twenty-five percent of the circumference of the bore 12 and standing inwardly approximately twice the thickness of the wall thickness of the sleeve tube/body member 2 . The standing tube stop lug 9 with recess 9 A and plateau 9 B in the bore 12 is configured to selectively mate with a corresponding tube notch 10 A or plateau 10 B of the proximal end of the sleeve tube/body member 2 . The height of the stop lug 9 from the bottom of the bore 12 is the same or slightly less than the depth of the tube notch depth. A long configuration is achieved when plateau 9 B aligns with plateau 10 B. A short configuration is achieved when recess 9 A is aligned with plateau 10 B. The sleeve tube/body member 2 may be manually rotated to an appropriate position to achieve a determined length, i.e., either a long version or short version. Thus, advantageously, the tube stop lug 9 with recess 9 A and plateau 9 B and corresponding tube notch 10 A and plateau 10 B enable selection of a first or second length of the trocar, to accommodate various cannulas and laparoscopic procedures.
[0048] Referring now to FIG. 4 , an exploded top view of an exemplary trocar and incision blade/safety shield cartridge assembly 8 according to principles of the invention is shown. The incision blade/safety shield cartridge assembly 8 includes a nose cone 4 with an aperture 15 for passage of the distal ends of an incision blade 5 and a correspondingly shaped retractable safety shield 6 . In an exemplary implementation, the incision blade 5 has a V-shaped cross section and a pointed distal end, with sharp leading edges 18 . The aperture 15 may be a central V-shaped axial through slot configured to snugly receive the distal ends of the incision blade 5 and the correspondingly shaped safety shield 6 , without impeding sliding extension and retraction of the safety shield 6 .
[0049] The nose cone 4 may be comprised of polyethylene, polycarbonate, ABS, other plastic resin or other material suitable for surgical applications. Advantageously, the conical shape of the nose cone 4 facilitates dilation of an incision to the full instrument diameter, thus minimizing trauma to the penetrated tissue. Optionally, the nose cone 4 may be lubricated with a biocompatible surface treatment, such as by coating the surface of the nose cone 4 with one of the family of parylene compounds, such as those available from Specialty Coating Systems, Inc., Indianapolis, Ind. Parylene compounds comprise a family of p-xylylene dimers that polymerize when deposited onto a surface to form a hydrophobic polymeric coating. For example, a nose cone 4 according to principles of the invention may be coated with polymerized dichloro-(2,2)-paracyclophane (Parylene C) or di-p-xylylene (Parylene N). Parylene monomers may be applied to the surface of the nose cone 4 by gas-phase deposition in a vacuum chamber. The coating may further facilitate entry of the instrument into a body cavity.
[0050] The cartridge assembly 8 is received in the distal end of the sleeve tube/body member 2 as illustrated in FIG. 3A . The nose cone 4 interlocks with the spring retainer housing 23 . A shoulder stop 16 provides an abutment which meets the distal end of the sleeve tube/body member 2 when the cartridge assembly 8 is installed. Male latches 17 provide mechanisms for engaging corresponding recesses 21 in the spring retainer housing 23 . A heel pocket recess 30 receives heel stops 19 of the incision blade 5 to lock the incision blade 5 in position, as shown in FIG. 6 .
[0051] The pointed, double beveled edge 18 of the V-shaped incision blade 5 produces a clean incision with a slight flap. The pointed, double beveled edge 18 of the V-shaped incision blade 5 is also illustrated in FIG. 9 . The V-shaped cross section for making a V-shaped incision is also clearly shown in FIGS. 10 and 12 . With minimal force, the incision blade 5 produces a V-shaped incision without tearing or otherwise causing unnecessary trauma to the tissue. The incision with the flap, which is formed by the intersecting beveled edges, may be closed with relatively few stitches, staples or other closure means. The flap may also be folded during insertion of an instrument to provide a generally rectangular opening.
[0052] The incision blade 5 has at least two different widths. A narrow region 20 along the sides of the incision blade 5 ensures that the sides of the safety shield 6 extend beyond the sides of the incision blade 5 when the safety shield is deployed (i.e., extended). Thus, the shield prevents possible tissue or organ laceration while the device is inside a body cavity, even if a surgeon accidentally contacts an internal organ. Concomitantly, a wider region along the sides of the incision blade 5 at the aperture 15 of the nose cone 4 ensures a snug fit, such that the blade 5 will not shift from side to side within the aperture 15 . Thus, the V-shaped incision blade is snugly positioned between the longitudal sides of the nose cones centrally located V-shaped axial through slot.
[0053] The safety shield 6 is configured to serve as a guard, seal and a surgical implement. The safety shield 6 may be made be comprised of plastic such as polyethylene, polycarbonate, ABS, other plastic resin or other material suitable for use in a surgical device. A blunt radius distal point 35 , as shown in the side and head-on views of FIGS. 10 and 11 , respectively, is provided to aid a surgeon in safely separating muscle fiber and to protect internal organs should accidental contact occur after the distal end of the device enters a body cavity. The safety shield 6 is configured to blend with the conical shape of the nose cone 4 when the shield 6 is fully retracted during a piercing procedure. The conforming streamlined contour of the safety shield 6 thus reduces resistance to penetration, tissue trauma during full instrument incision dilation and the risk of becoming plugged with loose tissue.
[0054] Furthermore, the safety shield is contoured to conform to the cross-sectional shape of the incision blade 5 , as illustrated in FIGS. 4 and 9 . Advantageously, the V-shape provides a thin geometry that reduces its drag or resistance against the abdominal wall tissue allowing rapid deployment through and immediately after a full width incision is produced by the V-shaped incision blade 5 but before the nose cone 4 has fully dilated the incision thereby offering nearly immediate internal organ protection.
[0055] Additionally, the safety shield 6 incorporates a forward travel stop 27 that maintains a maximum fully deployed blade shielded position. Upon penetrating a body cavity, resistance to the depressed safety shield 6 is relieved and the spring 5 causes the shield to rapidly deploy. Upon deployment, the travel stop 27 contacts the stop lug 26 . The spring-driven impact of the travel stop 27 with the stop lug 26 produces a sensible signal. The signal may be tactile and/or audible and/or visible. Indeed the construction and composition of the lug 26 and stop 27 may be tailored to maximize detection of such signals.
[0056] The forward travel stop 27 serves as a spring 22 abutment seat. Protruding rearward from the forward travel stop 27 is a shield spring post stop 28 that provides for spring centering/alignment and a reward stop for full retraction. A contact point with a housing spring post stop 29 defines a point of retraction wherein the edges of the safety shield conform to the conical shape of the nose cones 4 .
[0057] The spring retainer housing 23 is attached to the proximal end of the nose cone 4 during assembly by two sets of latching details, the latch/female 17 and the latch/male 21 interlock to one-another on opposing sides as illustrated in FIGS. 4 and 6 . The latch/male 21 incorporates a standing stop lug 26 that abuts the back end of the nose cone 4 and heel stop 19 of the V-shaped incision blade 5 , firmly securing and encapsulating the blade from movement within the heel pocket 30 , as shown in FIG. 6 . Additionally, as discussed above, the spring retainer housing 23 uses the standing stop lug 26 as a forward stop used by the V-shaped safety shield 6 to limit its travel and set the full deployment position. Furthermore, the latch/female 17 and the latch/male 21 interlocking is securely maintained when the assembly is installed into the sleeve tube/body member 2 due to the minimal clearance between the two components.
[0058] A housing spring post stop 29 provides a spring 22 centering/alignment standing post 29 for the spring proximal positioning and seat depth. The housing spring post stop 29 also provides a rearward contact stop for the V-shaped safety shields 6 spring post and stop 28 . Upon contact of the spring post and stop 28 with the housing spring post stop 29 , the V-shaped safety shield 6 is fully retracted thereby allowing the conical contours of the V-shaped safety shield 6 to blend with the contour of the nose cone 4 . Referring now to FIGS. 6A and 6B , the assembled cartridge assembly 8 with the safety shield 6 in its extended deployed position is shown. In the top view of FIG. 6A , it is apparent that the deployed safety shield 6 extends beyond the cutting edges of the incision blade 5 . Likewise, in the bottom view of FIG. 6B it is apparent that the cutting edge of the incision blade 5 does not extend beyond the deployed safety shield 6 . Concomitantly, the head-on view of FIG. 6C shows the incision blade 5 conforming generally to the shape of the safety shield 6 .
[0059] In sum, an incision blade/safety shield cartridge assembly 8 according to principles of the invention is comprised of a nose cone 4 , a V-shaped incision blade 5 , a V-shaped safety shield 6 , a spring 22 , and a safety shield spring retainer housing 23 . A trocar according to principles of the invention is comprised of an incision blade/safety shield cartridge assembly 8 , a sleeve tube/body member 2 and a handle 1 . Assembly of the incision blade/safety shield cartridge assembly 8 entails inserting the internal V-shaped incision blade 5 and safety shield 6 into nose cone 4 , placing the spring 22 between the safety shield spring centering/locating post 29 and the stop lug 26 , positioning the forward travel stop 27 of the safety shield 6 between the distal end of the spring 22 and the stop lug 26 , and coupling (e.g., via snap locks) the nose cone 4 to the safety shield spring retainer housing 23 . In this manner, the cartridge is assembled without need for bonding or other attachment means. The assembled incision blade/safety shield cartridge assembly 8 may then be mated to the tube 2 of a trocar according to principles of the invention, or any other trocar configured to mate with the cartridge assembly 8 .
[0060] The handle 1 is preferably comprised of plastic of polycarbonate, ABS or other plastic resin. The curved or mushroom shape fits a surgeon's palm for comfort and control. Handle ribs 24 ensure structural integrity while enabling mass/weight reduction for a substantial surgeon gripping diameter or size. The handle may be bonded or otherwise mechanically secured to the proximal end of the sleeve tube/body member.
[0061] The sleeve tube/body member 2 may be made from thin wall stainless steel tubing of polished or mat finish or of polycarbonate, ABS or other plastic resin. The blunt end or distal end, may receive the incision blade/safety shield cartridge assembly 8 to its full predetermined depth of the shoulder stop detail 16 . This blunt end may be square cut allowing a nearly gap free mating when the shoulder stop 16 surface abuts to the tube 2 during final assembly. Furthermore, the outside diameter of the portion of the incision blade/safety shield cartridge assembly 8 , which fits within the inside diameter of the sleeve tube/body member, has minimal clearance, thereby resulting in nearly mismatch free matching of the largest outside diameter of the nose cone 4 and the outside diameter of the sleeve tube/body member 2 .
[0062] A V-shaped indented staking detail 3 may be used for fixed retention of the internal incision blade/safety-shield cartridge assembly 8 . One or more other mechanical attachments may be provided to secure the cartridge assembly 8 at multiple locations about the periphery of the tube 2 . In an exemplary implementation, the point of the “V” of the staking detail 3 faces the distal end of the trocar. The point is pierced first, through the sleeve tube/body member and continues piercing and bending a V-shaped tab of metal downward and rearward into the receiving area designed for the V-shaped staking retention. This downward and rearward motion draws rearward and secures the incision blade/safety shield cartridge assembly, ensuring abutment of the distal, square cut end, of the sleeve tube/body member 2 and the mating abutment shoulder stop of the nose cone 4 .
[0063] The exemplary incision blade 5 of a trocar according to principles of the invention offers numerous advantages over the prior art. A V-shaped blade cutting contour that tapers to a pointed tip, improves incision and penetration capability by allowing for a small V-shaped incision which facilitates entry of the trocar body and a cannula. The incision blade 5 is preferably a V-shaped blade with surgical cutting edges which allows for a clean and precise V-shaped incision. The V-shaped incision consequently minimizes tearing of surrounding tissue when a cannula or other surgical instrument is inserted. This provides an important advantage over prior art blades with a single planar cutting edge that is conducive to tearing, and over prior art blades with three or more cutting edges that cause unnecessary trauma and increased risk of collateral injury. The blade design of a trocar according to principles of the invention reduces risk of collateral damage beacuse the V-shaped incision readily allows passage of the safety shield 6 and a cannula. This is due to the fact that the blade cutting contour of a trocar according to principles of the invention produces an incision with a foldable flap to allow better access to a body cavity with less unnecessary tearing and injury within the location being cut and surrounding area. While a V-shaped blade cutting contour is preferred, other flap forming configurations, such as L-shaped, U-shaped, W-shaped and the like also come within the scope of the invention.
[0064] Disadvantageously, multiple cutting edges in multiple planes, as known in the prior art, may not only cause unavoidable tearing of adjacent internal organs and muscle but also may cut unnecessarily large incisions during, laparoscopic procedures. This may result in, for example, pressurized carbon dioxide gas escaping from the area being treated. As insufflation is necessary for many laparoscopic procedures, the large incisions and loss of gas may result in the need for additional gas to be pumped into the internal area being treated or may result in the need for seals to be placed around the cannula in order to maintain proper insufflation. The novel cutting contour of the incision blade 5 of a trocar according to principles of the invention cuts a more precise and resilient incision that avoids the evacuation of pressurized gas which may occur during use of prior art devices. By better maintaining the integrity of insufflation, a trocar according to principles of the invention may reduce both the length of surgery and related costs.
[0065] Furthermore, the cutting contour of a trocar according to principles of the invention may be tapered to a degree of thinness not possible in, for example, a pyramidal configuration as is common in the prior art. In the assembly of a trocar according to principles of the invention, the incision blade cutting angles may be customized to suit particular locations on a body to be cut, particular procedures, and a surgeon's particular needs and preferences.
[0066] Of course, the incision blade 5 and the V-shaped blade cutting contour, as detailed above, could be applied to numerous trocars as are known in the art. Such other applications are intended to come within the scope of the invention.
[0067] The simplicity of the incision blade 5 and safety shield 6 of a trocar according to principles of the invention not only leads to greater reliability and increased safety, but it also improves the utility of a trocar. A cartridge assembly 8 according to principles of the invention has been intentionally designed to permit use with a variety of trocars and similar surgical tools without compromising its effectiveness. Additionally, those skilled in the art will appreciate that any compatible cannula may be employed with a trocar according to principles of the invention. The invention is not limited to any particular type of cannula.
[0068] The exemplary trocar may be utilized in surgery to provide a relatively small access opening through outer tissue and muscle layers into an internal body cavity. The cavity may be insufflated by the introduction of gas prior to use of the trocar. During a laparoscopic procedure, the trocar is coaxially aligned with the cannula. The distal end of the trocar is forced into a determined area of the body cavity. A V-shaped safety shield 6 is biased to initially extend beyond the piercing tip of the V-shaped incision blade 5 . As the shield 6 is forced against the body cavity tissue to be pierced, the shield retracts into the nose cone 4 and sleeve tube 2 member. When the body cavity is breached, a spring biasing member returns the blunt end of the safety shield 6 past the piercing tip of the incision blade 5 to prevent accidental puncturing or laceration of the internal organs by the sharpened point. Because the safety shield 6 is contoured After the trocar produces an access opening, the trocar is removed and the cannula may be left secured in place in the opening. Thus, the cannula provides an open conduit into the body cavity.
[0069] While an exemplary embodiment of the invention has been described in detail, it should be apparent that modifications and variations thereto are possible, all of which fall within the true spirit and scope of the invention. With respect to the above description then, it is to be realized that the optimum relationships for the components of the invention and steps of the process, to include variations in form, function and manner of operation, are deemed readily apparent and obvious to one skilled in the art, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed by the present invention. The above description and drawings are illustrative of modifications that can be made without departing from the present invention, the scope of which is to be limited only by the following claims. Therefore, the foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents are intended to fall within the scope of the invention.
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A trocar includes an incision blade/safety shield cartridge assembly, a sleeve body having a distal end and an opposite proximal end, and a handle. The incision blade/safety shield cartridge assembly includes a nose cone; a stationary incision blade adapted to produce a clean incision with a flap, such as a v-shaped incision; and a retractable safety shield that conforms to the shape of the incision blade, a spring, and a safety shield spring retainer housing. The safety shield retracts to a retracted position exposing the incision blade during piercing of a body cavity and rapidly extends to an extended position beyond the tip of the incision blade upon penetration of a body cavity, thereby guarding against unintended incision and/or puncture wounds.
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FIELD OF THE INVENTION
[0001] The invention relates generally to a system for maintaining and distributing sheets of photosensitive film media within a laser imaging machine. More particularly, it relates to a system configured to receive and open a cartridge of photosensitive film within the imager, and separate and deliver individual sheets of the photosensitive film media from the cartridge to a film transport system of the imager.
BACKGROUND OF THE INVENTION
[0002] Light sensitive, photothermographic film is used in many applications ranging from a standard photocopying apparatus, to graphic arts and/or medical imaging/recording printing systems. For example, in the medical industry, laser imaging systems employing photothermographic film are commonly used to produce photographic images from digital image data generated by magnetic resonance (MR), computer tomography (CT) or other types of scanners. Systems of this type typically include a laser imager for exposing an image on the photothermographic film, a thermofilm processor for developing the film through the application of heat, and an image management subsystem for coordinating the operation of the laser imager and the thermofilm processor. The resulting image is available for diagnostic use by medical radiologists and communications to referring physicians and their patients.
[0003] Generally speaking, a photosensitive film laser imager includes a film supply system, a film exposure assembly, a film processing station (or developer), a film dispensing area and a film transport system. Each of these components are associated within a relatively large imager housing.
[0004] Sheets of unexposed photosensitive film is normally stacked in a sealed, standardized film cartridge, for delivery to the imager. The standard film cartridge can be sealed by a foil cover. During use, the film cartridge is inserted into the film supply system of the imager. The film supply system normally includes mechanisms for unsealing the film cartridge and subsequently removing individual sheets of film. In this regard, the film supply system separates and delivers an individual sheet of photosensitive film from the film cartridge to the film transport system. The film transport system, in turn, delivers the individual sheet of film to the film exposure assembly. Within the film exposure assembly, photographic images are exposed on the film from image data (e.g., digital or analog) using a laser imager. The exposed sheet of film is then transported, via the film transport system, to the film processing station where the film is developed. After thermal processing, the film is cooled and transported to the film dispensing area where the final image is available to the user.
[0005] U.S. Pat. No. 6,139,005 (Nelson) and U.S. Pat. No. 6,260,842 (Nelson), both incorporated herein by reference, are directed to film supply systems for use with a photosensitive film imager.
[0006] While laser imagers have proven to be highly successful, several potential drawbacks may exist. For example, the film supply system is normally very complex, large and therefore expensive. To accomplish desired film separation, the standard film supply system normally includes several mechanisms and a number of independently driven parts which maneuver the film sheet in different directions to effectuate film separation. This complex approach to separating and delivering sheets of film is normally quite expensive.
[0007] Therefore, a substantial need exists for a film supply system configured to meet the design and operational constraints of a photosensitive film laser imager, in a cost-effective manner.
[0008] The film supply system of the present invention, also referred to as the Pickup Assembly, is comprised of an integrated pickup mechanism and a feed roller mechanism. The pickup mechanism separates the top sheet of film from the rest of the film supply/pack and lifts the film sheet into an open set of rollers in the feed roller mechanism. The feed roller mechanism then closes its set of transport rollers and transports the film into a Vertical Transport Assembly.
SUMMARY OF THE INVENTION
[0009] An object of the present invention is to provide a film supply system for use with a laser imager.
[0010] Another object of the present invention is to provide such a film supply system which is robust and compact in size.
[0011] These objects are given only by way of illustrative example, and such objects may be exemplary of one or more embodiments of the invention. Other desirable objectives and advantages inherently achieved by the disclosed invention may occur or become apparent to those skilled in the art. The invention is defined by the appended claims.
[0012] The present invention provides a film supply system for use with a laser imager. In one preferred embodiment, the film supply system includes a cartridge receiving apparatus associated with a film pick-up mechanism. The cartridge receiving apparatus is preferably configured to receive and maintain a cartridge of photosensitive film. The film pick-up mechanism, in turn, is associated with the cartridge receiving apparatus and is preferably configured to separate and deliver individual sheets of photosensitive film from the film cartridge to a film transport system.
[0013] According to one aspect of the invention, there is provided a film supply system for use in an imager to separate sheets of photosensitive media from a film cartridge and deliver individual sheet of the photosensitive media to a film transport system. The film supply system comprises: a frame for attachment of the film supply system within the imager; a heel plate pivotably attached to the frame and actuatable by a motor; and a cup plate pivotably attached to the heel plate, the cup plate including at least one suction cup for selectively engaging a sheet of the photosensitive media.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The foregoing and other objects, features, and advantages of the invention will be apparent from the following more particular description of the preferred embodiments of the invention, as illustrated in the accompanying drawings.
[0015] [0015]FIG. 1 generally shows a front view of a laser imager having a film supply system in accordance with the present invention.
[0016] [0016]FIG. 2 shows an isometric view of the film supply system in accordance with the present invention.
[0017] [0017]FIG. 3 shows an isometric view of a portion of the film supply system of FIG. 2.
[0018] [0018]FIG. 4 shows a side of the film supply system of FIG. 2 in a home position.
[0019] [0019]FIG. 5 shows a side of the film supply system of FIG. 2 in a film contact position.
[0020] [0020]FIG. 6 shows a side of the film supply system of FIG. 2 in a cups engaged position.
[0021] [0021]FIG. 7 shows a side of the film supply system of FIG. 2 in a pre-pump position.
[0022] [0022]FIG. 8 shows a side of the film supply system of FIG. 2 in a max bend position.
[0023] [0023]FIG. 9 shows an isometric view of a portion of the film supply system of FIG. 2.
[0024] [0024]FIG. 10 shows a side of the film supply system of FIG. 2 in a film lift position.
[0025] [0025]FIG. 11 shows a side of the film supply system of FIG. 2 in a home position.
[0026] [0026]FIG. 12 shows a side of the film supply system of FIG. 2 in a cups engaged position with a full film cartridge.
[0027] [0027]FIG. 13 shows a side of the film supply system of FIG. 2 indicating a roller gap position.
[0028] [0028]FIG. 14 shows a side of the film supply system of FIG. 2 in a maximum bend position with a full cartridge.
[0029] [0029]FIG. 15 shows a side of the film supply system of FIG. 2 in a home position with a full cartridge.
DETAILED DESCRIPTION OF THE INVENTION
[0030] The following is a detailed description of the preferred embodiments of the invention, reference being made to the drawings in which the same reference numerals identify the same elements of structure in each of the several figures.
[0031] [0031]FIG. 1 shows a front view of a laser imaging system 130 incorporating a film supply system in accordance with the present invention. The laser imaging system 130 generally includes an imager housing 132 , a film supply system 134 , a film exposure assembly 136 , a film processing station 138 , a film exit area 140 and a film transport system 142 . It should be understood that each of the components of the laser imaging system 130 are shown generally in FIG. 1. Further details on the laser imaging system 130 , and in particular the film supply system 134 , are described in greater detail below.
[0032] The film supply system 134 , the film exposure assembly 136 , the film processing station 138 , the film exit area 140 and the film transport system 142 are all disposed at various locations within the imager housing 132 . During use, a cartridge of photosensitive film 144 is placed within the film supply system 134 . Upon activation, the film supply system 134 retrieves a single sheet of photosensitive film (not shown). The sheet of photosensitive film is delivered by the film supply system 134 to the film transport system 142 for delivery to the film exposure assembly 136 . Within the film exposure assembly 136 , photographic images are exposed on the film from image data (e.g., digital or analog), using a laser imager. The thusly exposed film is then transported via the film transport system 142 to the film processing station 138 where the film is developed. After thermal processing, the film is cooled and transported via the film transport system 142 to the film exit area 140 . For ease of illustration, the film travel path is represented by dashed lines 146 .
[0033] As described in greater detail below, the film supply system 134 includes a cartridge receiving apparatus 148 and a film pick-up mechanism 150 .
[0034] As indicated above, the film supply system of the present invention, also referred to as the Pickup Assembly, is comprised of an integrated pickup mechanism and a feed roller mechanism. The pickup mechanism separates the top sheet of film from the rest of the film supply/pack and lifts the film sheet into an open set of rollers in the feed roller mechanism. The feed roller mechanism then closes its set of transport rollers and transports the film into a Vertical Transport Assembly.
[0035] The supply system of the present invention has a low profile design. It can be desirable for an imager to include more than one supply area, for example, a 3 film supply drawer system may be desired. As such, minimizing the height of the Pickup and Rollback Assemblies (i.e., the supply magazine ) is important to the overall height of the imager, every inches saved in the height of the supply magazine saves in the height of the imager. Another factor in the height of the supply magazine is the lengths of the transported film. For example, one film that may be used in an imager is a 18×24 cm size with a transported length of 18 cm. This 18 cm film length drives both the roller pitch in the imager, and the desired pitch between supply magazines because the magazines should try to match the roller pitch in the Vertical Transport Assembly otherwise the Vertical Transport design would not be symmetric. 172 mm is another Supply Magazine and Roller Pitch used in the imager.
[0036] Another feature of the present invention is a pickup head. The Pickup Assembly is configured to pickup most all size film in any Supply Magazine. As such, the Pickup head design should be no wider than the narrowest film width fed. If the narrowest film is 24 cm, or 240 mm. Thus, the width of the Pickup Head should be less than this value, clearance on both sides as the Pickup head to allow penetration of the film cartridge.
[0037] Another feature of the present invention is throughput. It is desirable that the throughput of an imager be high. Thus, the image must provide for such throughput.
[0038] Film supply system 134 is now more particularly described with reference to FIGS. 2 through 15.
[0039] [0039]FIG. 2 shows an isometric view of the film supply system in accordance with the present invention. As best shown in FIG. 2, Pickup Assembly 134 includes of a heel ( 7 ) that is pivotally attached to the pickup frame through two heel pins ( 9 ). The ends of the heel springs ( 8 ) are attached to arms ( 10 ) on the heel and a spring pin ( 6 ) mounted to the pickup frame. The heel ( 7 ) is actuated by a DC gear motor ( 11 ).
[0040] [0040]FIG. 3 shows an isometric view of a portion of the film supply system of FIG. 2. As shown in FIG. 3, cup pivot shaft ( 20 ) is pivotally attached to a front section of the heel ( 7 ). A pair of pivot arms ( 22 ), four carriage pins ( 29 ), and a cable arm ( 27 ) are rigidly attached to the cup pivot shaft ( 20 ). Two cup carriages ( 14 ) slide up and down on the carriage pins ( 29 ) and are biased outward away from the cup pivot shaft ( 20 ) by four carriage springs ( 28 ). Four e-rings ( 16 ) mechanically captivate the cup carriages ( 14 ) at the ends of the carriage pins ( 29 ). A pair of suction cups ( 13 ) and a silicone loop ( 15 ) is attached to each cup carriage ( 14 ). The suction cups are connected to a vacuum pump and solenoid valve through with silicone tubing. Preferably, all the suction cups are routed through the same line, when the vacuum is released by the solenoid valve, the vacuum is released to all cups at once. As such, if the vacuum seal is broken at any of the suction cups, the vacuum is released to all cups.
[0041] The end of the drive cable ( 18 ) loops around the cable pulley ( 17 ) which is pinned to the end of the cable arm ( 27 ). The drive cable loops around the drive pulley 19 and travels back towards the dc motor ( 11 ).
[0042] One end of the pivot spring ( 25 ) is attached to a pivot spring cable ( 26 ) and the other end to the heel ( 7 ). The other end of the pivot spring cable ( 26 ) attaches to the cable arm screw ( 24 ) which locks the cable arm ( 27 ) to the cup pivot shaft ( 20 ).
[0043] [0043]FIG. 4 shows a side of film supply system 134 of FIG. 2 in a first (home) position wherein. As shown, drive cable ( 18 ) loops over an idler pulley 33 , loops around a motor drive pulley ( 37 ), and then back around another idler pulley ( 39 ) and attaches to drive cable spring ( 35 ). The other end of the drive cable spring ( 35 ) attaches to a pin ( 36 ) which is fixed to the pickup frame. The idler pulley ( 39 ) is pinned to the end of the idler link ( 38 ) which pivots relative to the pickup frame at the axis of idler ( 33 ). The idler link ( 38 ) is biased clockwise, away from the drive cable spring ( 35 ) with the idler spring ( 32 ) attached to the frame at pin ( 31 ) and to the idler link ( 38 ) at pin ( 34 ). This idler link assembly takes the slack out of the drive cable ( 18 ) and prevents it from disengaging from the pulleys.
[0044] The pickup operation of the film supply system is now described with reference to FIGS. 2-15.
[0045] [0045]FIG. 4 shows the pickup in the home position. This is the position where the heel pads and the suction cups are at their highest points. A home sensor mounted to the heel engages a home sensor flag at the top of the pickup frame to indicate this position.
[0046] [0046]FIG. 5 shows the film supply system in a film contact position. In FIG. 5, the dc motor ( 11 ) has turned counterclockwise which effectively feeds out the drive cable ( 18 ) allowing the heel ( 7 ) to rotate counterclockwise until the heel pads ( 21 ) make contact with the bottom of the a cartridge ( 41 ) with only 1 film in it, (i.e., the figure shows a nearly empty cartridge).
[0047] As the heel ( 7 ) rotates down onto the film in the film cartridge ( 41 ), the arms ( 10 ) on the heel lift upwards and the resulting moment arm length between the axis of the heel springs ( 8 ) and the heel pins ( 9 ) steadily increases. This increases the magnitude of the resulting heel pad ( 21 ) force against the film when it makes contact with the film. Preferably, the downward force against the film is at a maximum at the bottom of the cartridge ( 41 ), preferably in the range of 10 to 15 lbs. total.
[0048] During the travel down from the home position (as shown in FIG. 4) to the film contact position (as shown in FIG. 5), the cup carriages ( 14 ) and suction cups ( 13 ) are nearly in a vertical position ( 90 dig from the film plane). Although the cup pivot spring ( 25 ) and cup pivot cable ( 26 ) wrap around the cable arm ( 27 ), creating a moment about the axis of the cup pivot shaft ( 20 ) which bias's the cup carriage assemblies towards a horizontal position, the preferred 10 to 15 lb. force on the drive cable ( 18 ) from the main heel springs ( 8 ) creates its own counteracting moment about the axis of the cup pivot shaft ( 20 ) which is proportional to the length of the cable arm ( 27 ). This moment created by the drive cable ( 18 ) and main heel springs ( 8 ) keeps the cup carriages ( 14 ) in a nearly vertical position until the heel pads ( 21 ) contact the film.
[0049] Referring now to FIG. 6, there is shown the film supply system in a cups engaged position. As shown in FIG. 6, once the heel pads ( 21 ) make contact with the film, the heel ( 7 ) can no longer rotate and the main heel springs ( 8 ) can no longer influence the position of the cup carriage ( 14 ). At this point, the rotation of the cup carriage ( 14 ) and the cup pivot shaft ( 20 ) is governed by the cup pivot spring ( 25 ) which rotates the cup carriage assembly counterclockwise as shown in FIG. 6. The motor driver ( 12 ) continues to turn counterclockwise, feeding out more cable, which allows the cup carriage assembly to rotate until the suction cups ( 13 ) plant down onto the film. This is referred to as the Cups Engaged Position.
[0050] The cable arm ( 27 ) is shaped ( 42 ) such that the moment arm is at a maximum in this Cups Engaged position. This rotational moment creates a suction cup ( 13 ) force against the film which helps create the vacuum seal.
[0051] A parameter in the calculation of the film engagement (shown later) is the suction cup depth, which is the distance between the leading edge of the film and the center if the planted suction cups.
[0052] [0052]FIG. 7 shows the film supply system in a pre-pump position. Once the suction cups ( 13 ) plant onto the film, a vacuum seal is made between the cups and the film. At this point, the dc motor ( 11 ) reverses direction and the drive cable ( 18 ) begins retracting. As the drive cable ( 18 ) pulls upwards on the cable pulley ( 17 ), the cup carriage assembly rotates clockwise as shown in FIG. 7, lifting the from edge of the film. The position shown in FIG. 7 is the Pre-Pump position. The pickup operation includes pumping the film between the Cups Engaged Position and the Pre-Pump Position from 1-3 times to separate the top sheet(s) of film from the bulk of the film pack. This operation is critical because if the cup carriage assembly rotates further, the force required to bend several sheets of film could cause the heel pads ( 21 ) to lift off the film and cause one or more films to kick forward onto the adhesive of the cartridge.
[0053] It is preferred that no more than 5 sheets of film should be left on the lifted film stack to prevent the heel ( 7 ) from lifting when rotating the cup carriage assembly to the next position. It has also been noted that the narrow width film sizes (e.g., 8×10 inch, and 10×12 inch) need more pre-pump cycles to break the pack.
[0054] An additional mechanism which can be used to aid in the separation of film sheets are the two silicone loops ( 15 ) that are mounted to the cup carriages. When the top sheets of film lift upwards away from the pack, these silicone loops press downward on the film creating a wave form along the leading edge of the film. This wave form produces additional relative motion between film sheets which helps separate them.
[0055] Referring now to FIG. 8 here is shown the max bend position. After the pre-pump operations, the dc motor ( 1 ) continues to rotate clockwise and the cup carriage assembly rotates clockwise to an approximately vertical position called the maximum bend position (as shown in FIG. 8). At this position, the de motor ( 11 ) stops and the film is held with an approximately 90 degree bend for the maximum bend time, roughly 1-2 seconds.
[0056] The beam strength of the film and the wave generated in the leading edge of the film by the silicone loops ( 15 ) help separate the top sheet of film. As with the pre-pump process, the pickup cycles for 1-3 times between the maximum bend position and the cups engaged position.
[0057] As the film rotates from 0 to 90 degrees, the suction cups ( 13 ), which are vacuum sealed to the film surface, must slide downwards towards the cup pivot shaft ( 20 ) on the carriage pins ( 28 ). This cup sliding motion accounts for the accumulation of film, the radius of curvature, as the film bends. If the cups where prevented from sliding, they would tear off the film. The Cup Carriage Movement (referenced in FIG. 8 as dimension x) is the measure of the cup carriage assembly movement along its carriage pins ( 29 ). The total cup carriage movement from a 0-90 degree rotation is approximately 25 mm.
[0058] [0058]FIG. 9 shows a further illustration of the film supply system.
[0059] [0059]FIG. 10 shows the film lift position. When the heel leaves the maximum bend position, the heel ( 7 ) lifts off the film. The film separation process must be successful (only one sheet attached to cups) at this point or, either multiple sheets would be fed, or, 1 or more sheets would be kicked forward onto the adhesive of the cartridge.
[0060] As the pickup lifts the film, the pivot rollers ( 23 ) attached to the pivot arms ( 22 ) contact an angled shelf ( 5 ) on the pickup frame. This causes the cup pivot shaft ( 2 ) and attached cup carriage assembly to rotate counterclockwise until the carriage assembly is back to a horizontal position. This has the effect of moving the leading edge of the film up, over the lower drive roller ( 4 ) and then forward in between the open roller set.
[0061] [0061]FIG. 11 shows the pickup in its final Home Position. (The leading edge of the film is noted as LE.) The cup carriage assembly is in a horizontal position with the leading edge of the film LE in between the open roller set. At this point, the feed roller mechanism is energized, and the idler roller closes onto the drive roller ( 4 ). Once the film is secured between the feed rollers, the solenoid valve is energized and the vacuum is released to the suction cups ( 13 ). Once the suction cups ( 13 ) detach from the film, the film is then ready to be transported into the vertical assembly.
[0062] One dimension related to the performance of the pickup assembly is the engagement, shown in FIG. 11 as dimension E. The engagement is the horizontal distance from the leading edge of the film to the center of the drive roller ( 4 ). The engagement can be thought of as the amount the film overlaps the drive roller ( 4 ). It is important because if the engagement is too low, the film could drop out of the rollers, or, be skewed as it feeds through the rollers. If there is too much engagement, the film edge could hit the drive roller when its lifted from the cartridge. This will be shown in the following sections.
[0063] Two design parameters that enter into the calculation of the engagement include the drive roller depth, and the drive roller height. The drive roller depth DRD is the horizontal distance between the leading edge of the film and the center of the drive roller ( 4 ). The drive roller height DRH is the vertical distance from the top of the polypropylene liner in the bottom of the cartridge to the center of the drive roller ( 4 ).
[0064] When the pickup travels to the home position, the pickup home sensor engages a flag at the top of the pickup frame. If this sensor were to fail, the pickup heel would be prevented from rotating any further by hard stops at the top of the frame. The dc motor ( 11 ) would keep running because of the sensor failure, and the motor pulley ( 37 ) would continue turn until it went over top dead center. Once the heel could no move, the drive cable ( 18 ) could no longer retract any further. The cable extra length required to allow the motor pulley to travel over TDC comes from the extension of the cable spring ( 35 ). This mechanism has been designed to prevent the geared dc motor from stalling during a home sensor, or software failure. Stalling such a powerful motor could cause substantial damage to the motor itself or other pickup components.
[0065] [0065]FIG. 12 shows the pickup in the Cups Engaged Position with a full film cartridge. Here the value of the Suction Cup Depth SCD is approximately 6 mm less than the Suction Cup Depth at the bottom of the cartridge because of the dimensional relationships between the pivot point of the heel, the pivot point of the cup carriage, and the depth of the film pack.
[0066] [0066]FIG. 13 shows the another parameter in the performance of the pickup. The roller gap RG is defined as the minimum clearance between the leading edge of the film and drive roller ( 4 ) as the film rotates past the roller, either in traveling up to the maximum bend position, or down to the cups engaged position. The roller gap is important because if it becomes less than zero and there is a substantial interference between the film edge and the drive roller, the pivot spring ( 25 ) may not have enough force to rotate the cup carriage assembly down to the cups engaged position. This roller gap is highly dependent on the drive roller depth and drive roller height. To increase the amount of engagement, the drive roller depth can be increased, but this reduces the roller gap and increases the risk of film edge/drive roller interference.
[0067] [0067]FIG. 14 shows the pickup at the maximum bend position with a full cartridge. Because the height of the pickup assembly has been minimized, the pivot rollers ( 23 ) just come into contact with the angled shelf ( 5 ) of the frame at this position when the cartridge is full.
[0068] [0068]FIG. 15 shows the pickup in its home position with a full cartridge. Since the suction cup depth was less in the full cartridge than the empty cartridge, the resulting engagement is also less by approximately 6 mm. This indicates that any engagement related problems in the pickup will be at its worse when the cartridge is full. Design optimization involves increasing the drive roller depth until the roller gap is at its minimum allowed value. This will maximize the engagement for both the empty and full cartridges.
[0069] The invention has been described in detail with particular reference to a presently preferred embodiment, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention. The presently disclosed embodiments are therefore considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the appended claims, and all changes that come within the meaning and range of equivalents thereof are intended to be embraced therein.
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A film supply system for use in an imager to separate sheets of photosensitive media from a film cartridge and deliver individual sheet of the photosensitive media to a film transport system. The film supply system comprises: a frame for attachment of the film supply system within the imager; a heel plate pivotably attached to the frame and actuatable by a motor; and a cup plate pivotably attached to the heel plate, the cup plate including at least one suction cup for selectively engaging a sheet of the photosensitive media.
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FIELD OF THE INVENTION
The invention relates to a positive dobby having a baulk, on the ends of which are arranged controlled draw hooks which are hinged thereto through bearing bolts, wherein the machine has stop rails and draw and/or push knives, which release and limit the movement of the baulk.
BACKGROUND OF THE INVENTION
The weaving machines which are controlled by means of dobbies are constantly being further developed with respect to higher operating needs. The mass accelerations of the heddle frame result in higher forces acting onto the control members and an increased demand for a playfree operation.
These strong stresses which occur in the positive dobbies of the Hattersley construction lead to a quick wear at the ends of the baulk. It has been heretofore suggested to provide the ends of the baulks with reinforcing elements, for example in the form of ring segments, which serve to absorb the occurring support forces. These ring segments on the baulk ends are caught and held during the control period between the stop rails and the repulsion knives. Movements are thereby detected at the ends of the baulk, which movements result in a quick wear in the case of heavily stressed machine parts. The cause for this lies, on the one hand, in the complex construction of the draw hook baulk end not being able to be manufactured sufficiently exactly in the common form and at a reasonable expense and this, therefore, results in a nonpermissible play relative to the stop rail and the repulsion knife and the draw and support knife. As a result, impacts which occur due to the relative movement between the parts lead to an excessive overload of the machine parts. On the other hand, the ring segments cause at the ends of the baulk, due to the line contact point to the stop rail and to the repulsion knife, a specific load to be applied, through which common building materials are overloaded. Simultaneously with the creation of these high specific surface pressures, the lubricating film is pierced at the contact points. Soon dents occur due to a plastic deformation of the material and a material removal at the contact points occurs due to the lack of lubrication at these points. Due to the complex forms and relative movements, the wear continues in an accentuated manner. This wear leads first to unsteady frame movements and requires then the replacement of the worn parts, which results in undesirable interruptions in the operation.
The purpose of the invention is to reduce the friction path and the specific load and initial play which exists due to inexactnesses.
This is inventively achieved in the above-mentioned dobby by the external part of the bearing ends of the controllable draw hooks resting directly against the stop rails or repulsion knives, which causes the bearing ends to be caught during the control period of the draw hooks between the stop rail and the repulsion knife. The bearing end of the draw hook thus contacts the stop rail and the repulsion knife instead of the ends of the baulk. In the normal position, the bearing end of the draw hook is caught playfree between these two parts, which causes the draw hook to be held stationarily.
The inventive arrangement attains the purpose of facilitating a construction of the sensitive part in the dobby in such a manner that a more exact manufacture with a smaller initial play becomes easily attainable and that the support point between the end of the baulk and the stop rail or the repulsion knife results in a smaller specific stress and a simultaneously reduced friction path. At the same time, it became possible to shorten the swanneck between the bearing end of the draw hook and the elongated draw hook shaft, which swanneck was acted upon by the relatively voluminous ring segment, and to obtain a stronger form of the draw hook, which under a load tends to bend correspondingly less, namely elastically deforming along the length and thus forwards less interferingly movements to the weaving heddle frame.
This new arrangement results in the space between the stop rail and the repulsion knife (control period), the body of the draw knife and the repulsion knife and the support or holding knife and the stop rail being now occupied only by one and the same controllable individual element, namely the draw hook, wherein in place of the ring segment the outer surface of the bearing end of the draw hook rests directly selectively on the stop rail, the repulsion knife or during the control period on both simultaneously. The position of the bore in the bearing end may have a relatively large inexactness, without influencing the function of the machine. The outer form of the bearing end at the mentioned contact points may have a cylindrical or different convex form. In addition the outer form of the bearing end, in particular in the cylindrical version thereof, may be enclosed by a mounting shoe, for example of plastic, and rotatably limited with respect to the bearing end, which shoe is provided on the outside preferably with a surface, which forms an operative connection with the countersurface on the stop rail or the repulsion knife.
BRIEF DESCRIPTION OF THE DRAWINGS
Various exemplary embodiments are illustrated in the drawings, in connection with which the invention will be explained.
In the drawings:
FIG. 1 is a schematic side view of the design of a positive dobby, wherein the draw hooks are supported in a conventional manner freely rotatably on bolts at the end of the baulk and said end of the baulk rests against the repulsion knife or against the stop rail;
FIG. 2 is an enlarged view of the end of the baulk which has been cut open along the line II--II of FIG. 3;
FIG. 3 is a cross-sectional view of the end of the baulk according to FIG. 1 and taken along the line III--III of FIG. 2;
FIG. 4 is a view of the end of the baulk according to the invention, which end has been cut open;
FIG. 5 is a cross-sectional view of said baulk end and taken along the line V--V of FIG. 4;
FIG. 6 is a view of the baulk end, which has been cut open, according to a modification of the invention;
FIG. 7 is a view of the baulk end, which has been cut open, according to a further modification of the invention;
FIG. 8 is a cross-sectional view of said baulk end and taken along the line VIII--VIII of FIG. 7; and
FIG. 9 is a perspective view of the mounting shoe of this embodiment.
DETAILED DESCRIPTION
A positive dobby according to FIG. 1 is part of the prior art and has principally a baulk 1, which consists of two plates 10 which extend parallel to one another and which are connected at each of their ends by a bolt 7. One draw hook 5 is freely rotatably supported on each bolt at the end of the baulk. Reference numeral 2 identifies the draw knives and reference numeral 8 identifies the repulsion knives for releasing the movement of the draw hooks. In the rear rest position, the ends of the baulk rest on a stop rail 6, wherein the ends of the draw hooks remote from the baulk engage in a lifted position thereof behind a holding knife 3. The movement of the baulk 1 is transmitted through a rocking lever 9, which is pivotally supported on an axle 4, to the heddle frame by structure which is not shown.
In this known construction of the end of the baulk and the support of the draw hook 65 according to FIGS. 2 and 3, same sits freely rotatably on the bolt 67 connecting the two plates 60 of the baulk together. A segment of a ring 68 of a relatively large diameter is secured concentrically with respect to the bolt 67 and between the plates 60, which ring segment extends laterally beyond the edges of the plates and also outwardly beyond the bearing end 69 of the draw hook and on the one side rests against the stop rail 6 and on the other side against the repulsion knife 8. During a swinging back and forth movement of the illustrated draw hook or of the baulk end, the ring segment 68 reaches relative to the draw hook 65,69 the position illustrated in dash-dotted lines in FIG. 2. Therefore, the draw hook 65 must extend up from the bearing end 69 over a long swanneck 66 and can only then be bent. This results in a weakening and a loss of stability of the draw hook due to an elastic deformation thereof. The ring segment 68 lies during the movement of the draw hook always on a line against the repulsion knife 8, the stop rail 6 or during the control operation against both parts. A reciprocal up and down movement can occur, and also a relatively large swivel movement, which results in a friction and thus causes wear. This is a disadvantage. In contrast to this there exists the advantage that the draw hook 65 remains at any time freely swingable, which makes its movement easier in particular during reading-in through a free gravity fall.
FIGS. 4 and 5 illustrate an inventive modification. The baulk again consists of two plates 70, the ends of which are connected together through the bolt 77. The bearing end 79 of the draw hook 75 is supported freely rotatably on the bolt, wherein the outside circumference of the bearing end extends radially beyond the baulk plates and the bearing end rests against the repulsion knife 8 and the stop rail 6. Due to this direct abutment, the position of the axis of the bore in the bearing end 79 and the axis of the bolt 77 in the baulk end may have a relatively large inexactness, without interfering with the function of the draw hooks 75. The swinging baulk 70 is classically supported by the bolt 77 in the bearing end 79 and is only yet indirectly connected to the stop rail 6 and the repulsion knife 8. Since only an extremely small relative movement remains between the bearing end and the stop rail and the repulsion knife, hardly any wear will occur any longer at the contact points. The contact pressure between bearing end 79 and repulsion knife 8 or stop rail 6 is the same as in the case of the ring segment 68 in FIGS. 2 and 3.
In the modified embodiment according to FIG. 6, the bearing end 89 has an approximately cubic shape. Compared with the surfaces on the repulsion knife 8 or the stop rail 6, the contact surfaces are constructed slightly convexly, which results in a surface contact rather than a line contact therebetween. A higher loading capability of the contact point is obtained and the wear on the outer surfaces of the bearing end is less.
In order to reduce the support pressure per surface unit between the bearing end 99 and the repulsion knife 8 or stop rail 6, the bearing end 99 of the draw hook 95 is, according to the modification in FIGS. 7 to 9, embedded rotatably in a mounting shoe 98. The side surfaces of this shoe rest at any time fully on the knife 8 or the rail 6, however, they move in parallel direction during the up and down movement of the baulk which is formed by the plates 90. This shoe facilitates a large-surface contact between the bearing end and the repulsion knife 8 or the stop rail 9. The shoe can for example due to its extremely large contact surfaces consist of plastic. Its position in the space is always assured through the close contact either with the repulsion knife and/or the stop rail.
In the case of all three last described inventive modifications, a long swanneck is not needed between the draw hook 75,85 or 95 and the bearing end 79,89 or 99, namely the draw hook has therefore an elongated shape. In spite of this playfree mounting of the bearing end between repulsion knife and stop rail, the draw hook must, however, be swingable through a few degrees to accommodate the reading-in and reading-out movement, which is achieved due to the rounding of the bearing end.
As mentioned above, the advantage of the described dobby is that the bearing end of the draw hook carries out only yet a small swivel movement (hook control) relative to the stop rail and the push knife, while the working baulk rotates only in the bearing bore of both draw hooks. In the first case, the bearing end absorbs the small friction operation without any damage worth mentioning and in the second case the baulk operates with a classically constructed shaft bearing. Furthermore, the considerable support forces of the bearing end on the stop rail and on the repulsion knife with reasonable specific pressures can be absorbed by the parts, if the mentioned mounting shoe is utilized. The requirement to fill in the spacing between the stop rail 6 and the repulsion knife 8, the body of the draw knife 2 and the repulsion knife and the holding knife 3 and the stop rail 6 through the controllable member so that the end of the baulk 10 is always locked or driven playfree, is met according to the invention by having only one single element, the draw hook 5, serve as a power transmitter which is to be precisely manufactured. The distances between the outer form of the bearing end 79,89,98/99, the connecting surface 20 for the draw knife 2 and the support surface 30 for the holding knife 3 and the diameter of the bearing end are decisive for precision purposes in determining the sizes of the draw hooks 5,75,85,95. Only three dimensions must be precisely maintained for the play freedom on said draw hook, while the old solution included five dimensions, in addition to two inexact conditions during the assembly. Due to the omission of the relatively voluminous ring segment in the swinging baulk end, it is possible to remarkably shorten and at the same time widen the long swanneck which has heretofore been dimensioned only narrow, between the bearing end of the draw hook and the elongated draw hook shaft. Through this, the draw hook receivesan elongated form which under a load reacts with a lesser longitudinal expansion as a result of the elastic bending action and thus is able to transmit more exactly the movement of the draw knife onto the heddle frame.
Although particular preferred embodiments of the invention have been disclosed in detail for illustrative purposes, it will be recognized that variations or modifications of the disclosed apparatus, including the rearrangement of parts, lie within the scope of the present invention.
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A draw hook having a bearing end, the outside circumference of which projects beyond the end of the baulk and serves simultaneously as stop against the recoil or repulsion knife and the stop rail. The drawing force for the movement of the heddle frame occurs from the draw hook directly through the bolt onto the baulk. The reaction and the holding force act directly onto the bearing end of the draw hook.
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STATEMENT OF RELATED APPLICATIONS
This patent application is based on and claims the benefit of German Patent Application No. 10 2012 005 199.9 having a filing date of 16 Mar. 2012.
BACKGROUND OF THE INVENTION
Technical Field
The invention relates to a method for drying laundry, wherein air for drying the laundry is heated by a burner and, at least during a part of the drying operation, at least a part of the air used to dry the laundry is fed back to the burner as recirculating air, if need be together with fresh air, and to a dryer for laundry, comprising a drum for receiving the laundry to be dried and comprising at least one burner for heating air which serves for the drying.
Prior Art
Dryers for commercial laundries possess at least one burner, preferably a gas burner, for heating air which is used for drying. The air heated by the burner is passed through a preferably rotationally drivable drum containing the laundry to be dried. The air here absorbs moisture from the laundry to be dried. The moist air is afterwards led as waste air into the open and/or is fed back as recirculating air to the at least one burner and reheated by this.
At the beginning of the drying, the air leaving the drum contains the most humidity. This air cannot, or can only in small part, be reused as recirculating air. It must therefore, at least for the most part, be passed out of the dryer. At the beginning of the drying, only a small amount of recirculating air is therefore being carried. A large amount of fresh air is then fed, at least for the most part, via the burner to the dryer. As a result of this very large fresh air component, the at least one burner gets sufficient combustion air. At the conclusion of the drying operation, air having only a small amount of humidity leaves the drum. A relatively large amount of recirculating air and only a small amount of fresh air are then fed to the burner. The at least one burner then contains only very little fresh air or no fresh air at all, with the result that the burner works uneconomically. In many cases, an incomplete combustion with undesirable soot formation can ensue.
The object of the invention is to provide a method and a dryer for drying laundry, which can be operated with a relatively large recirculating air component, or with only recirculating air, economically and without negative impacts on combustion.
A method for the achievement of this object is a method for drying laundry, wherein air for drying the laundry is heated by a burner and, at least during a part of the drying operation, at least a part of the air used to dry the laundry is fed back to the burner as recirculating air, if need be together with fresh air, characterized in that the fresh air is transported to the burner at least during a part of the drying process. According to this, the fresh air is transported to the at least one burner at least during a part of the drying process. As a result of the active transport of fresh air to the burner, the fresh air is virtually blown or forced into the burner. A type of charging of the burner with fresh air occurs. As a result, the burner is also then supplied with sufficient fresh air if the recirculating air is returned in full or for the most part to the at least one burner without this adversely affecting the combustion. The drying can hence be realized with more recirculating air than previously. The inventive method thereby provides more economical drying.
A further advantageous embodiment of the method provides for, where necessary, feeding fresh air to the recirculating air after the recirculating air has been warmed by the respective burner. This happens before the warmed recirculating air has reached the laundry to be dried. In this way, only that quantity of fresh air which is necessary to the optimal operation of the burner needs to be fed to this same. If required, additional fresh air can be added directly to the warmed recirculating air, which can lead to more economical drying by, for example, increasing the amount of air available for drying the laundry.
An advantageous refinement of the method provides for the fresh air to be fed under pressure, preferably through at least one fan or a blower, to the burner. This type of transport of the fresh air to the at least one burner represents the simplest and most effective charging of the burner. Through adjustment of the fan speed, the quantity of fresh air fed to the burner can be adjusted or controlled in accordance with requirements, so that the respective burner receives as much fresh air as it requires, based on the respective recirculating air component. The burner can thus receive that quantity of fresh air which is required for the, in each drying phase, optimal operation, wherein the quantity of fresh air can be increased the greater the recirculating air component becomes which is returned to at least one burner.
A further advantageous embodiment of the method provides for, where necessary, fresh air to also be fed behind the respective burner to the recirculating air warmed by this same. This happens before the warmed recirculating air has reached the laundry to be dried. In this way, only that quantity of fresh air which is necessary to the optimal operation of the burner needs to be fed to this same. Fresh air which is required over and above this can be fed directly to the warmed recirculating air. That too leads to more economical drying.
A dryer for the achievement of the object stated in the introduction is a dryer for laundry, comprising a drum for receiving the laundry to be dried and comprising at least one burner for heating air which serves for the drying, characterized in that an air flow generator for the transport of fresh air to the burner is assigned to the at least one burner. In this dryer, it is provided to assign to the at least one burner an air flow generator for the transport of fresh air to the burner. The at least one air flow generator ensures a virtually forced supplying of fresh air to the burner, in that the air flow generator virtually pumps and/or forces fresh air into the burner, to be precise particularly when, due to a relatively large recirculating air component, the burner can no longer automatically draw in the fresh air necessary for optimal combustion.
Advantageously, the air flow generator is assigned to a supply line for fresh air to the respective burner, or to a common supply line for all burners. The fresh air can be transported by the at least one air flow generator in the at least one supply line directly to the or each burner.
A further advantageous embodiment of the dryer provides that the at least one air flow generator is configured to generate a variable stream of fresh air to the burner. As a result, the fresh air can be adjusted or controlled in accordance with requirements. A sufficient quantity of fresh air for optimal operation, in particular for optimal combustion, is thereby fed to the respective burner.
In one advantageous embodiment of the dryer, the air flow generator is configured as at least one fan. If a plurality of burners are present, a dedicated fan is preferably assigned to each burner, though one fan can also be jointly assigned to all burners. As a result, each burner can be specifically and, if necessary, individually supplied with fresh air in sufficient quantity.
A preferred refinement of the invention provides, behind the at least one burner, a preferably variable and/or closable feed opening for fresh air which can be mixed to the air warmed by the burner.
It can preferably be provided that at least one fan or at least one blower for the generation of a recirculating air flow, and/or a closable or variable waste air outlet for at least a part of the recirculating air, are provided. The at least one fan can generate a specific recirculating air flow, in particular a recirculating air flow having a desired flow velocity and/or a desired recirculating air stream. The closable or variable waste air outlet serves to regulate the recirculating air component which is returned to the at least one burner and, having been warmed, is fed from this back to the laundry. That part of the moist air which is not used as recirculating air can be led off into the open for evacuation of the moisture which accrues when the laundry is dried in the dryer.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred illustrative embodiment of the invention is explained in greater detail below with reference to the drawing, wherein:
FIG. 1 shows a schematic cross section through a dryer,
FIG. 2 shows a schematic cross section through the dryer according to FIG. 1 , with arrows for illustration of the air flows, and
FIG. 3 shows a schematic horizontal section III-III through an upper part of the dryer in the region of a burner.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The dryer represented schematically in the figures serves for the highly effective and energy efficient drying of laundry. Such a dryer is used, above all, in commercial laundries. In the dryer which is shown here, air for drying of the laundry is heated by a single burner 10 . The dryer can also, however, have a plurality of burners 10 arranged in parallel or in series. The burner 10 can be constituted both by a gas burner and by an oil burner.
The dryer possesses an outer housing 11 , preferably a closed, box-like housing 11 , in which a drum 13 , which can be driven in rotary motion about a horizontal rotational axis 12 , the said burner 10 , a recirculating air fan 14 and, further below, the described air guide ducts are disposed.
The rotationally drivable drum 13 serves to receive the laundry to be dried. It possesses a loading and unloading opening (not shown). In particular the casing 15 of the cylindrical drum 13 is of air-permeable configuration to enable air used for the drying to flow through the drum 13 and the initially damp laundry present therein. The drum 13 is rotatably mounted in a lower compartment 16 of the housing 11 .
The drum 13 is partially surrounded at a short distance from the cylindrical casing 15 by air-impermeable, arc-shaped walls 17 and 18 . The walls 17 and 18 lie on a circular path running concentrically around the rotational axis 12 , whereby the air-impermeable walls 17 and 18 surround the cylindrical casing 15 of the drum 13 at a short distance apart for the formation of a narrow gap 19 between the casing 15 of the drum 13 and the walls 17 and 18 . Each of the preferably equal-sized walls 17 and 18 extends over about 120° to 150°, preferably about 135°, of the periphery of the drum 13 . In this way, between transverse rims, running parallel to the rotational axis 12 , of different walls 17 and 18 are formed openings which are left free by these same and are diametrically opposing, to be precise an upper air inlet opening 20 and a lower air outlet opening 21 . Mutually facing, spaced-apart transverse rims of the walls 17 and 18 are sealed in the region of the air inlet opening 20 , with respect to a horizontal partition 23 demarcating the lower compartment 16 from an above-situated upper compartment 22 , by transverse walls 24 and 25 . In addition, a lower transverse rim of the (in FIG. 1 ) right-hand wall 17 is separated by a horizontal wall 26 to the nearest (left-hand) external wall 27 of the housing 11 .
In the upper compartment 22 of the housing 11 is located, at a distance from the external wall 27 , the recirculating air fan 14 , though this can also be in the form of a different air flow generator, for example a blower. In addition to the recirculating air fan 14 , there is also arranged in the upper compartment 22 , roughly in the middle, the burner 10 , to be precise such that a schematically indicated elongate flame tube 28 for generating a plurality of adjacent flames runs parallel to the rotational axis 12 . The axes of the flames run horizontally, to be precise transversely to the rotational axis 12 . Alternatively, the burner 10 can also be configured such that it generates just a single horizontal flame, extending transversely to the rotational axis 12 .
In the shown illustrative embodiment, the burner 10 is housed in the upper compartment 22 . For this purpose, a rear wall 29 is assigned to the burner 10 on the rear side. Above and beneath the burner 10 are located parallel, horizontal air guide walls 30 , 31 , which are both connected to the rear wall 29 . Parallel, free edges 32 of the air guide walls 30 and 31 form a preferably elongate, vertical air outlet opening 33 of the housing surrounding the burner 10 and made up of the rear wall 29 and the air guide walls 30 and 31 . The substantially fully open air outlet opening 33 thus forms a wide-slot opening or wide-slot nozzle. The air outlet opening 33 is distanced from an external wall 34 of the housing 11 , which external wall lies opposite the external wall 27 of the housing 11 . Similarly, the upper air guide wall 30 is distanced from an upper top wall 35 of the housing 11 of the dryer. Consequently, the rear wall 29 , which extends only up to the upper air guide wall 30 , ends also at a distance below the top wall 35 of the housing 11 .
In a bevelled upper, right-hand corner region between the horizontal top wall 35 and the vertical (right-hand) external wall 34 is located an air vent 36 . Below the air vent 36 is provided, inside the upper compartment 22 , a recirculating air flap 37 . The recirculating air flap 37 is pivotable about a horizontal pivot axis 38 , preferably by a drive (not shown). The recirculating air flap 37 is pivotable to the point where it, on the one hand, in an open setting completely closes off the air vent 36 and, on the other hand, in a closed setting extends the free edge 32 of the air guide wall 30 above the burner 10 to the external wall 34 and thereby forms a seal. Between the said extreme settings, optional intermediate settings of the recirculating air flap 37 are possible.
By virtue of the above-described configuration of the housing 11 , in particular of the lower compartment 16 and of the upper compartment 22 , a specific air flow can be induced in the dryer. Thus, the air outlet opening 21 opens out into a backflow chamber 39 closed off by the wall 18 , the transverse wall 25 , the wall 26 and the external wall 27 . By an opening (not shown in the figures) in the partition 23 , the backflow chamber 39 in the lower compartment 16 is connected to a backflow chamber 40 in the upper compartment 22 . This backflow chamber 40 is bounded by the partition 23 , the top wall 35 , an upper part of the external wall 27 , the rear wall 29 behind the burner 10 and the air guide wall 30 , distanced from the top wall 35 , above the burner 10 .
Between the upper part of the external wall 34 and the air outlet opening 33 situated at a distance therefrom, the chamber, surrounding the burner 10 , between the air guide walls 30 and 31 , the transverse walls 24 , 25 and the air inlet opening 20 into the drum 13 is formed an inflow chamber 41 . Via the inflow chamber 41 , the upper compartment 22 and the lower compartment 16 are also connected to each other by an appropriate opening in the partition 23 . When the recirculating air flap 37 is closed, the backflow chamber 40 and the inflow chamber 41 can be separated from each other. By the middle setting (shown in FIG. 1 ) of the recirculating air flap 37 , a partial connection of the backflow chamber 40 to the inflow chamber 41 and a partial opening-up of the air vent 36 is adjustable.
According to the invention, an air flow generator is assigned to the burner 10 . This is represented symbolically in FIG. 3 . This particular illustrative embodiment relates to an air flow generator configured as a fan 42 . The air flow generator can also be formed by a plurality of fans 42 . Through an intake opening (not shown), the fan 42 draws in fresh air from outside the housing 11 of the dryer and transports this to the burner 10 , preferably into the burner 10 . As a result of the lateral arrangement of the fan 42 next to the housing 11 , supply air or fresh air is transported or blown by the fan into the housing 11 in a direction parallel to the rotational axis of the drum 13 . The fresh air transported by the fan 42 into the housing makes its way inside the burner 10 , for which purpose it flows through the housing surrounding the burner 10 . If need be, it can be provided to transport the fresh air through the elongate flame tube 28 , to be precise preferably together with the gas to be combusted by the burner 10 . It is also conceivable, however, to feed the supply air or fresh air transported by the fan 42 to the inside of the burner 10 past the outside of the flame tube 28 or around the burner 10 .
The fan 42 can be driven by, for example, an electric motor 43 . Preferably, the speed of the electric motor 43 is variable or controllable or can be regulated. The throughput of fresh air or supply air through the fan 42 can thereby be altered and thus adapted to requirements. A desired stream of fresh air can thereby be transported to the burner 10 .
Opening out into the inflow chamber 41 , behind the air outlet opening 33 between the air guide walls 30 and 31 , viewed in the direction of flow, is a fresh air socket (not represented in the figures) disposed on a wall of the housing 11 . The opening of the fresh air socket is preferably variable in cross section. It is also conceivable for the fresh air socket to be able to be totally shut off. Via the fresh air socket, additional fresh air can be fed to the inflow chamber 41 (in the direction of flow) behind the burner 10 and/or outside this same. The quantity of fresh air is variable by altering the cross section of the fresh air socket. The fresh air supply via the fresh air socket can also be totally cut off.
The inventive method is explained in greater detail below with reference to the previously described dryer with reference to, in particular, FIG. 2 :
The drying operation commences with the supply of air 44 heated by the burner 10 through the inflow chamber 41 and the air inlet opening 20 to the rotationally driven drum 13 in which the laundry to be dried is found. As the air 44 flows along the laundry, which initially is still very damp, the air absorbs a large amount of moisture. As a result, relatively moist air 45 leaves the drum 13 through the air outlet opening 21 . The moist air 45 flows through the backflow chamber 39 in the lower part 16 into the backflow chamber 40 in the upper compartment 22 , where it is transported onward by the recirculating air fan 14 .
The moist air 45 containing, at the start of the drying operation, a high moisture component is initially, with the recirculating air flap 37 completely or almost completely closed, evacuated fully or for the most part through the air vent 36 from the housing 11 of the dryer, as waste air 46 . As replacement for the evacuated waste air 46 , fresh air is fed to the dryer from outside. This happens mainly through the burner 11 , where the fresh air fed from outside serves as combustion air. This fresh air is initially drawn in automatically by the burner 10 . For the support of the air supply to the burner 10 , it can also already be provided in this drying stage, however, for fresh air to be transported to the burner 10 through the fan 42 . Additionally or alternatively, further fresh air can, where necessary, be fed behind the burner 10 directly to the inflow chamber 41 .
As the drying process progresses, the moisture content in the moist air 45 declines. Then a part of the moist air 45 is fed as recirculating air past the burner 10 and/or through the burner 10 to the drum 13 containing the laundry to be dried. For this purpose, the recirculating air flap 37 is partially opened by being pivoted in the clockwise direction (related to the representation in FIG. 2 ) about the pivot axis 38 . The recirculating air flap 37 is opened sufficiently wide for the desired recirculating air stream to set in, i.e. a specific moist air component 45 is again fed as recirculating air 47 to the drum 13 and a remaining moist air component 45 is passed through the air vent 36 as waste air 46 into the open. That part of the moist air 45 which is passed through the air vent 36 as waste air 46 into the open is replaced by fresh air, which the fan 42 transports to the burner 10 or which can still be drawn in automatically by the burner 10 . This fresh air is passed through the burner 10 and here serves as combustion air. The air leaves the burner 10 as heated air 44 , which in the inflow chamber 41 mixes with the recirculating air 47 and, together with this same, is re-fed as heated air 44 to the drum 13 .
In dryers, in particular of the kind for commercial laundries, recirculating air 47 is employed in order to reuse the thermal energy in the moist air 45 and avoid having to reheat so much cold fresh air. The recirculating air component 47 is therefore gradually increased with increasing drying time. To this end, the recirculating air flap 37 is gradually opened further, so that it increasingly closes the air vent 36 and little moist air 45 having still considerable residual heat escapes through the air vent 36 into the open.
As the component of moist air 45 which has been reused and returned to the burner 10 , i.e. recirculating air 47 , increases, the burner 10 is itself able to draw in only little fresh air from outside. Sufficient fresh air is then no longer available to the burner 10 . This gives rise to an unfavorable or incomplete combustion, which, inter alia, can lead to harmful soot formation. It is therefore provided according to the invention to transport fresh air through the fan 42 to the burner 10 as the recirculating air component 47 increases. The burner 10 is then boosted or charged virtually with fresh air, which is forced or pumped through the fan 42 to the burner 10 . The burner 10 thereby receives sufficient fresh air for optimal combustion, whereby, in the end phase of the drying, drying can be realized with more recirculating air than has hitherto been normal, or with recirculating air only.
If, due to the fresh air transported by the fan 42 to the burner 10 , only recirculating air 47 is employed at the end of the drying operation, so that the whole of the moist air 45 is then reused as recirculating air 47 , then the recirculating air flap 37 lies fully open, in that, as a result of having been pivoted up to the air vent 36 , it closes this off, so that no moist air 45 can any longer flow as waste air 46 through the air vent 36 into the open and the whole of the moist air 45 can be fed back to the burner 10 as recirculating air. The burner reheats the recirculating air, so that the thereby heated recirculating air is fed back to the drum 13 containing the almost dry laundry.
The moist air 45 used as recirculating air 47 can be passed, wholly or partially with the fresh air transported by the fan 45 to the burner 10 , through the burner 10 . If the moist air 45 used as recirculating air is led only partially through the burner 10 , a part of the moist air 45 is led past the burner 10 , likewise as recirculating air, to join before the air outlet opening 33 with the air 44 heated by the burner 10 and/or warmed recirculating air, so that the recirculating air 47 , and the air 44 warmed by the burner 10 and likewise formed from recirculating air 47 , can be fed in its entirety through the inflow chamber 41 back to the drum 13 containing the laundry.
If the dryer is operated completely or for the most part with recirculating air 47 , behind the air outlet opening 33 a bit more fresh air can, where necessary, be fed from outside directly to the inflow chamber 41 . This is generally unnecessary, however, in the case of complete or almost complete recirculating air operation.
The fresh air transported by the fan 42 to the burner 10 and through this same is variable in quantity by appropriate controlling of the speed of the fan 42 . It is thereby possible to alter both the stream of fresh air to and through the burner 10 and the pressure of the fresh air. The burner 10 can thereby be charged or boosted more or less strongly according to the recirculating air component 47 .
At the start of the drying operation, when little circulating 47 is employed, the fan 42 , if need be, can be totally switched off, so that the burner 10 then automatically draws in the necessary fresh air. Only once the recirculating air component increases, in particular predominates, or only recirculating air 47 is used, is the fan 42 started up, so that fresh air, preferably under pressure, is then transported to the burner 10 or blown into the burner 10 , the pressure and/or the quantity of fresh air which is transported by the fan 42 to the burner 10 rising continuously with the increase in the recirculating air component 47 . Where the dryer is operated only with recirculating air 47 , the stream of fresh air and/or the pressure of the fresh air, by appropriate operation of the fan 42 , reach a maximum.
REFERENCE SYMBOL LIST
10 burner
11 housing
12 rotational axis
13 drum
14 recirculating air fan
15 casing
16 lower compartment
17 wall
18 wall
19 gap
20 air inlet opening
21 air outlet opening
22 upper compartment
23 partition
24 transverse wall
25 transverse wall
26 wall
27 external wall
28 flame tube
29 rear wall
30 air guide wall
31 air guide wall
32 edge
33 air outlet opening
34 external wall
35 top wall
36 air vent
37 recirculating air flap
38 pivot axis
39 backflow chamber
40 backflow chamber
41 inflow chamber
42 fan
43 electric motor
44 air
45 moist air
46 waste air
47 recirculating air
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A method for providing fresh air fed through a fan to a burner of a dryer, thereby charging the burner, when the dryer is operated with recirculating air. In commercial dryers in which the drying air is heated by a burner, it is customary to reuse the moist air leaving a drum containing the laundry to be dried as recirculating air. The recirculating air component is increased with increasing drying of the laundry. At the end of the drying operation, when the moist air no longer contains as much moisture as at the start, the moist air is used as recirculating air. The burner then no longer gets enough combustion air, which leads to an incomplete combustion. The dryer can be operated with a higher recirculating air component, an optimal combustion being guaranteed through the charging of the burner with fresh air. The invention permits more economical drying.
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This application is a continuation-in-part of United States patent application Ser. No. 768,783, filed Aug. 23, 1985 abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention:
This invention relates to the art of papermaking, particularly to treating paper products with milk and then high temperature to improve its properties, including wet stiffness, wet tensile strength and bursting strength.
2. Description of the Prior Art:
There is currently considerable interest in improving various properties of paper and boards. Quantifiable paper properties include: dry and wet tensile strength, folding endurance, stiffness, compressive strength, and bursting strength, among others. Which qualities should desirably be enhanced depends upon the intended application of the product. In the case of milk carton board, for example, stiffness is of particular importance, whereas for linerboard, wet strength, folding endurance, and high humidity compression strength may be more important.
All of these properties can be measured by well-known standard tests. As used herein, then, "wet strength" means wet tensile strength as measured by American Society for Testing and Materials (ASTM) Standard D829-48. "Folding endurance" is defined as the number of times a board can be folded in two directions without breaking, under conditions specified in Standard D2176-69. "Stiffness" is defined as flexural rigidity and is determined by the bending moment in g-cm. "Linerboard", as used herein, is a medium-weight paper product used as the facing material in corrugated carton construction, and is usually made from pulp produced by the kraft process. Folding carton board is a medium to heavy weight paper product made of unbleached and/or bleached pulps having basis weights from 40-350 g/m 2 .
Prior workers in this field have recognized that high-temperature treatment of paperboard can improve its wet strength. See, for example E. Back, "Wet stiffness by heat treatment of the running web", Pulp & Paper Canada, vol. 77, No. 12, pp. 97-106 (Dec. 1976). This increase has been attributed to the development and cross-linking of naturally occurring lignins and other polymers, which phenomenon may be sufficient to preserve product wet strength even where conventional synthetic resins or other binders are entirely omitted.
It is noteworthy that wet strength improvement by heat curing has previously been thought attainable only at the price of increased brittleness (i.e., reduced folding endurance). Embrittled board is not acceptable for many applications involving subsequent deformation, and therefore heat treatment alone, to develop the wet strength of paperboard and carton board, has not gained widespread acceptance. Heat treatment has most successfully been used to produce hardboard. It has not been practiced on paper having latex or milk additives.
It is therefore an object of the invention to produce paperboard having both improved stiffness and wet strength, and adequate folding endurance.
With a view to the foregoing, a process has been developed which dramatically and unexpectedly increases not only the stiffness and wet tensile and bursting strengths of various paperboards, but also preserves their folding endurance. In its broadest sense, the invention comprises steps of (1) applying a natural latex, preferably milk, to paperboard, and then (2) heating the paperboard so treated to an internal temperature of at least 400° F. (205° C.) for a period of time sufficient to increase the wet strength of the board. We prefer to raise the internal temperature of the board to at least 450° F. (232° C.) during the heat treating step, as greater stiffness and wet strength are then achieved. This may be because at higher temperatures, shorter step duration is necessary to develop bonding, and there is consequently less time for fiber degradation to occur. Also, shorter required durations enable one to achieve higher production speeds for a treating apparatus of a given length.
While the heat treatment may cover a range of temperatures and durations, these factors are interrelated. Higher temperatures requires a heat treating step of shorter duration, and vice-versa. For example, at 550° F. (289° C.), a duration of 2 seconds has been found sufficient to obtain the desired improvements, while at 420° F., considerably longer is required.
Optionally, the paper may then be subjected to a third step of rewetting the board immediately after the heat treatment and while the paper temperature is above 100° C. to at least 1% mositure by weight. These steps are followed by conventional drying and/or conditioning of the treated board. It is to be understood that steps 2 and 3 can be repeated several times.
Of course, those skilled in the art will recognize the necessity of the product conditioning to a normal moisture content after this very hot treatment. See, for example, U.S. Pat. No. 3,395,219. A certain amount of remoisturizing is normally done, and in fact must be done prior to use or testing. Conventional rehumidification is done after the product has substantially cooled, at temperatures well below 100° C.
Our rewetting treatment differs from conventional conditioning in that we add water, by spraying or otherwise, to a very hot and dry paper or board at the very end of the heat treatment, without intermediate cooling. It is important that the water be applied to the product while it is still hot, certainly above 100° C. (212° F.), and preferably above 205° C. (400° F.). Another heat treatment or drying step may follow rewetting, on or off the machine, during a subsequent operation such as sizing, coating or calendering.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The invention can be carried out either on a conventional papermaking machine or off the machine in an oven after a size-press, but for high speed production, a continuous papermaking machine would be used.
In either event, the paper fibers are first treated by adding a latex. Latex is a water-based suspension of protein, and milk is one naturally occurring latex. The additive may be mixed with the pulp prior to sheet forming, or it may be added to a formed sheet by spraying or other means. The wet web is conventionally pressed to unite the pulp fibers and remove excess water. Following wet pressing, the paper product is heat treated.
For the heat treatment step to be effective, the initial water content of the web must be in the range of 1-20% by weight and preferably within the 10-15% range. Sufficient heat is then applied to the board to achieve an internal paper temperature of at least 400° F. (205° C.). The heat can be applied in the form of hot air, superheated steam, heated drying cylinders, infrared heaters, or by other means. Alternatively, the paper may be heat-treated in an oven after a size-press. After heat treatment, if the paper is conventionally conditioned, improved wet strength will be observed.
Preferably, however, the paper is immediately rewetted following the heat treating step, and while it is still hot. To rewet the paper, water may be applied by spraying, immersion or other means. Even though one effect of the water application is to cool the paper, it is important that the paper not cool substantially before the water application. We have found that the best results are obtained when the paper is rewetted while the web is substantially still at heat treating temperature. In a continuous machine, this goal is achieved by placing the water applicator as close as possible to the exit of the heat treatment unit.
The heat treated and rewetted paper is dried, if necessary, and is then cooled, conditioned, and calendered according to conventional procedure.
The invention has been practiced as described in the following examples. An improvement in product quality will be apparent from an examination of the test results listed in the tables below.
EXAMPLE 1
A commercial bleached kraft board was sized with different potato starch (PS)/milk mixtures. The starch and milk solution concentrations were 8% and 4% polymer by weight, respectively. The size press pressure was adjusted to yield a polymer add-on of 2.4% by weight. A part of the samples was conventionally dried ("C" in the Tables) on Emerson speed drier, model 10 at 230° F. (110° C.). Another portion of the samples was heat treated ("HT" in the Tables) at 400° F. (205° C.) for 30 seconds and rewetted immediately after heat treatment. After conditioning for 48 hours under standard conditions (70° F., 65% relative humidity), the samples were tested. The results of testing appear in Table 1.
TABLE 1______________________________________ PS:MILK PS:MILK NO MILK 50:50 70:30PROPERTIES (C) (HT) (C) (HT) (C) (HT)______________________________________Basis weight 160.1 150.3 168.5 165.9 165.4 164.0(lb/3000 ft.sup.2)Caliper 18.9 19.0 19.2 18.6 19.2 18.6(mils)Corrected 158/75 164/ 161/81 182/91 145/ 166/81Stiffness 88 69g-cm(MD/CD)% Stiffness -- 3.8/ 1.9/8 15.2/21 -8.2/ 45.1/8Improvement -9 -8(MD/CD)______________________________________
EXAMPLE 2
Board as in Example 1 was treated with a 50:50 mixture of starch and acrylic latex (Rohm-Maas Rhoplex HA-16). The starch and latex concentrations were 8% and 50% respectively. The size press pressure was adjusted to achieve a polymer add-on of 10.5%. A portion of the samples was conventionally dried on Emerson Speed drier, model 10 at 230° F. (110° C.). Another portion of the samples was heat treated at 400° F. (250° C.) for 30 seconds. All the samples were conditioned for 48 hours under standard conditions. The resultant sample properties are listed in Table 2.
TABLE 2______________________________________ NO ADDITIVE PS:LATEXPROPERTIES C HT C HT______________________________________Basis weight 160.1 l50.3 179 177(lb/3000 ft.sup.2)Caliper 18.9 19.0 19.2 18.6(mils)Corrected 158/75 164/88 166/92 188/99Stiffness,g-cm(MD/CD)% Stiffness -- 3.8/-9 5.1/22.6 19.5/32Improvement(MD/CD)______________________________________
EXAMPLE 3
A commercial kraft unbleached linerboard having a kappa number of 105 and Canadian Standard Freeness of 720 mls was sized and treated as in Example 1. All the samples were conditioned for 48 hours under standard conditions. The resultant board properties are listed in Table 3.
TABLE 3______________________________________ NO ADDITIVE PS:MILK 50:50 WHOLE MILKProperties C HT C HT C HT______________________________________Basis weight 135.2 128.0 137.1 138.6 136.6 138.2lb/3000 ft.sup.2Caliper 12.9 12.4 l2.9 12.6 13.0 12.4(mils)Dry Tensile 64.6/ 62.4/ 66.1/ 72.0/ 65.9/ 74.7/lb/in MD/CD 21.6 20.6 22.4 26.2 21.1 22.3Wet Tensile 8.1/ 9.6/ 6.9/ 15.3/ 6.2/ 16.4/lb/in MD/CD 3.1 3.3 2.5 4.9 2.3 5.5Stiffness 14.8/ 14.0/ 16.5/ 16.0/ 16.3/ 15.8/g-cm 5.0 5.0 5.3 6.3 4.8 4.8STFI comp. 46.7/ 21.7/ 46.7/ 51.0/ 44.2/ 48.6/MD/CD 24.5 44.6 26.6 27.7 22.6 21.5MIT Fold -- 703/ -- 1027/ -- 1101/MD/CD -- 424 -- 618 -- 724Mullen 147.3 121.3 164.0 156.7 15.7 148.7______________________________________
EXAMPLE 4
The same board as in Example 3 was sized and treated as in Example 3, using a 50% potato starch, 50% latex mixture. All the samples were conditioned for 48 hours under standard conditions. The resultant product properties are listed in Table 4.
TABLE 4______________________________________ NO ADDITIVE PS:LATEX 50:50Properties C HT C HT______________________________________Basis weight 135.2 128.0 143.7 145.0lb/3000 ft.sup.2Caliper 12.9 12.4 13.1 12.3(mils)Dry Tensile 64.6/ 62.4/ 83.5/ 82.2/lb/in MD/CD 21.6 20.6 31.2 30.1Wet Tensile 8.1/ 9.6/ 13.7/ 24.8/lb/in MD/CD 3.1 3.3 4.7 9.6Stiffness 14.8/ 14.0/ 15.3/ 16.5/g-cm 5.0 5.0 6.8 6.0STFI comp. 46.7/ 21.7/ 53.6/ 57.0/MD/CD 24.5 44.6 29.6 31.0MIT Fold -- 703/ -- 939/MD/CD -- 424 -- 559Mullen 147.3 121.3 191.0 178.0______________________________________
EXAMPLE 5
Samples of bleached kraft board were sized with various additives and then processed as in Example 1. The results of testing appear in tables 5.1-5.7.
TABLE 5.1______________________________________BLEACHED BOARD + NO ADDITIVES HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/3000 ft.sup.2) 209.1 208.4 209.4Caliper (0.001 in) 21.9 21.4 21.5Tensile Dry MD 88 108 101(lb/in) CD 52 60 58% Stretch MD 2.3 2.6 2.4 CD 3.5 4.1 3.9Tensile Wet MD 19 37 31(lb/in) CD 17 25 22% Stretch MD 2.0 2.4 2.2 CD 2.5 3.7 3.5Mullen Burst Dry 89 99 92(psi) Wet 20 37 39Corrected Taber MD 270 292 288Stiffness gm-cm CD 145 161 165______________________________________
TABLE 5.2______________________________________BLEACHED BOARD + STARCH(8% Aqueous) (4.8% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/3000 ft.sup.2) 212.0 213.7 210.2Caliper (0.001 in) 21.3 20.8 20.2Tensile Dry MD 124 121 128(lb/in) CD 69 60 69% Stretch MD 3.9 3.6 3.4 CD 5.1 4.8 4.8Tensile Wet MD 30 35 28(lb/in) CD 15 17 18% Stretch MD 2.9 2.9 2.8 CD 5.4 5.2 5.5Mullen Burst Dry 150 148 149(psi) Wet 29 39 41Corrected Taber MD 294 308 315Stiffness gm-cm CD 168 172 181______________________________________
TABLE 5.3______________________________________BLEACHED BOARD + SKIM MILK(3.5% Proteins) (5% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/3000 ft.sup.2) 208.2 210.4 208.1Caliper (0.001 in) 21.9 21.0 20.5Tensile Dry MD 95 107 108(lb/in) CD 57 61 65% Stretch MD 2.5 2.5 2.4 CD 4.0 4.2 4.1Tensile Wet MD 29 42 47(lb/in) CD 16 23 31% Stretch MD 3.0 2.9 3.0 CD 5.4 5.6 6.0Mullen Burst Dry 117 113 109(psi) Wet 35 54 62Corrected Taber MD 297 312 321Stiffness gm-cm CD 138 150 158______________________________________
TABLE 5.4______________________________________BLEACHED BOARD & CONDENSED MILK(7.0% Proteins) (4.8% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/3000 ft.sup.2) 215.6 214.7 212.7Caliper (0.001 in) 21.5 21.1 20.8Tensile Dry MD 112 110 118(lb/in) CD 54 58 59% Stretch MD 2.5 2.5 2.5 CD 3.4 4.0 3.4Tensile Wet MD 27 52 51(lb/in) CD 14 25 25% Stretch MD 2.4 2.8 2.8 CD 5.1 5.6 6.1Mullen Burst Dry 111 110 115(psi) Wet 28 57 48Corrected Taber MD 301 312 333Stiffness gm-cm CD 160 159 167______________________________________
TABLE 5.5______________________________________BLEACHED BOARD & RECONSTITUTED DRY MILK(14% Proteins) (4.8% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/3000 ft.sup.2) 231.0 225.7 222.5Caliper (0.001 in) 22.0 21.4 20.9Tensile Dry MD 123 127 128(lb/in) CD 66 69 71% Stretch MD 2.6 2.7 2.4 CD 4.0 4.1 3.1Tensile Wet MD 26 39 42(lb/in) CD 14 23 22% Stretch MD 2.8 3.4 3.5 CD 5.4 6.4 6.3Mullen Burst Dry 143 139 121(psi) Wet 33 46 51Corrected Taber MD 335 396 398Stiffness gm-cm CD 214 221 241______________________________________
TABLE 5.6______________________________________BLEACHED BOARD + STARCH: RECONSTITUTED DRYMILK (7% Proteins) (5.0% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/3000 ft.sup.2) 223.6 223.2 220.2Caliper (0.001 in) 22.4 21.9 21.3Tensile Dry MD 123 127 132(lb/in) CD 67 70 70% Stretch MD 2.9 2.9 2.5 CD 4.3 4.6 3.4Tensile Wet MD 27 38 43(lb/in) CD 16 22 24% Stretch MD 2.8 3.1 3.2 CD 5.6 6.0 5.9Mullen Burst Dry 129 136 132(psi) Wet 29 42 45Corrected Taber MD 333 381 379Stiffness gm-cm CD 188 215 219______________________________________
TABLE 5.7______________________________________BLEACHED BOARD + IMPREGNATED WITH1% CaCl.sub.2 AND CONDENSED MILK(7% Proteins) (5% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/3000 ft.sup.2) 219.9 261.6 211.2Caliper (0.001 in) 22.0 21.5 20.5Tensile Dry MD 106 96 105(lb/in) CD 58 59 58% Stretch MD 2.5 2.4 2.1 CD 4.3 4.2 3.0Tensile Wet MD 24 45 41(lb/in) CD 15 22 24% Stretch MD 2.7 3.0 2.8 CD 5.3 5.2 4.2Mullen Burst Dry 114 88 92(psi) Wet 29 38 35Corrected Taber MD 330 349 340Stiffness gm-cm CD 164 172 174______________________________________
EXAMPLE 6
Samples of unbleached kraft linerboard were subjected to the treatment of Example 5; the resulting products were tested as in Example 5. The results appear in the following tables.
TABLE 6.1______________________________________UNBLEACHED BOARD (LINERBOARD) + NOADDITIVES HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/1000 ft.sup.2) 49.5 49.8 49.6Caliper (0.001 in) 13.4 13.3 13.4Tensile Dry MD 99 115 105(lb/in) CD 42 49 47% Stretch MD 3.5 3.6 3.5 CD 4.2 4.4 4.4Tensile Wet MD 9 27 24(lb/in) CD 4 13 11% Stretch MD 1.4 2.2 2.1 CD 3.8 4.4 4.3Mullen Burst Dry 105 158 152(psi) Wet 10 49 41STFI (lb/in) MD 40 46 44 CD 28 31 32______________________________________
TABLE 6.2______________________________________UNBLEACHED BOARD + STARCH(8% Aqueous) (5.0% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/1000 ft.sup.2) 50.4 49.7 49.0Caliper (0.001 in) 13.7 13.7 13.2Tensile Dry MD 126 128 147(lb/in) CD 67 54 64% Stretch MD 5.5 4.7 5.5 CD 6.6 5.7 5.6Tensile Wet MD 16 25 25(lb/in) CD 7 12 12% Stretch MD 2.1 2.4 2.4 CD 4.8 5.6 5.8Mullen Burst Dry 222 196 190(psi) Wet 18 34 38STFI (lb/in) MD 47 48 53 CD 32 30 35______________________________________
TABLE 6.3______________________________________UNBLEACHED BOARD + SKIM MILK(3.5% Protein) (4.9% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/1000 ft.sup.2) 49.7 48.7 48.0Caliper (0.001 in) 13.5 13.6 12.6Tensile Dry MD 109 119 1l8(lb/in) CD 43 45 54% Stretch MD 3.9 4.4 4.0 CD 4.l 5.5 5.1Tensile Wet MD 15 32 30(lb/in) CD 6 15 15% Stretch MD 1.7 2.6 2.8 CD 4.0 6.2 6.3Mullen Burst Dry 133 183 164(psi) Wet 16 53 58STFI (lb/in) MD 47 58 54 CD 27 32 31______________________________________
TABLE 6.4______________________________________UNBLEACHED BOARD + CONDENSED MILK(7.0% Proteins) (4.9% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/1000 ft.sup.2) 52.3 50.8 48.6Caliper (0.001 in) 13.6 13.6 12.5Tensile Dry MD 103 98 115(lb/in) CD 48 52 50% Stretch MD 3.5 2.6 3.6 CD 5.1 5.3 4.5Tensile Wet MD 12 38 36(lb/in) CD 5 15 14% Stretch MD l.5 2.8 2.7 CD 4.3 6.0 6.6Mullen Burst Dry 144 149 143(psi) Wet 12 68 63STFI (lb/in) MD 44 42 53 CD 26 34 32______________________________________
TABLE 6.5______________________________________UNBLEACHED BOARD + RECONSTITUTED DRY MILK(14% Proteins) (4.8% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/1000 ft.sup.2) 53.6 53.3 51.0Caliper (0.001 in) 14.1 13.6 12.5Tensile Dry MD 125 139 139(lb/in) CD 53 61 66% Stretch MD 3.4 4.5 4.6 CD 5.3 5.6 4.8Tensile Wet MD 11 40 41(lb/in) CD 5 18 17% Stretch MD 1.6 3.8 3.5 CD 4.3 6.8 7.1Mullen Burst Dry 166 199 178(psi) Wet 14 95 81STFI (lb/in) MD 48 66 62 CD 31 40 34______________________________________
TABLE 6.6______________________________________UNBLEACHED BOARD + STARCH: RECONSTITUTEDDRY MILK (7.0% Proteins) (4.8% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/1000 ft.sup.2) 51.4 51.9 50.9Caliper (0.001 in) 13.7 13.5 12.7Tensile Dry MD 126 147 142(lb/in) CD 45 56 51% Stretch MD 4.1 4.5 4.1 CD 4.6 5.2 4.2Tensile Wet MD 13 34 39(lb/in) CD 5 15 14% Stretch MD 1.6 3.2 3.3 CD 3.8 6.3 6.0Mullen Burst Dry 168 193 171(psi) Wet 16 69 70STFI (lb/in) MD 49 66 64 CD 31 40 41______________________________________
TABLE 6.7______________________________________UNBLEACHED BOARD + IMPREGNATED WITH 1%CaCl.sub.2 AND CONDENSED MILK(7% Proteins) (5.1% Add-on) HT + HTPROPERTIES CONTROL REWET ONLY______________________________________Basis Wt. (lb/1000 ft.sup.2) 50.7 50.8Caliper (0.001 in) 13.8 13.0Tensile Dry MD 110 125(lb/in) CD 54 54% Stretch MD 3.5 3.5 CD 6.0 4.4Tensile Wet MD 34 40(lb/in) CD 16 16% Stretch MD 3.9 2.9 CD 6.1 6.8Mullen Burst Dry 164 149(psi) Wet 65 54STFI (lb/in) MD 45 54 CD 30 33______________________________________
The tables above show clearly that notable increases in wet strength, without substantial degradation of other qualities, are produced by heat treating paper having latex additives as described above. Use of the rewetting procedure is seen to improve folding endurance.
Inasmuch as the invention is subject to many variations and changes in detail, the foregoing description and examples should be regarded as illustrative of the invention defined by the following claims.
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The stiffness, wet strength and bursting strength of paper is improved by adding a latex such as milk to the paper and then subjecting the paper to steps of high temperature treatment and immediate rewetting.
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BACKGROUND OF THE INVENTION
The present invention relates to an apparatus for automatically and simultaneously ironing shirt front, rear and top portions, which has been specifically designed to be used in the cloth article making industry.
As is known any cloth article must be suitably ironed in order to remove therefrom the cloth folds.
On the other hand, at present for ironing shirts there are only available apparatus provided for ironing the front and rear portions of the shirts.
Then, by using such an apparatus, it is necessary to carry out other shirt processing steps, for ironing, for example, the sleeves, the shoulders and neck of the shirts.
These further processing steps, as it should be apparent require a lot of expensive labor which negatively affects the cost of the finished cloth article.
Moreover, in conventional shirt ironing apparatus, the partially ironed shirts are manually taken from their supporting dummy, in order to be subjected to a further shirt body ironing step, which further increases the cost of the finished product.
SUMMARY OF THE INVENTION
Accordingly, the aim of the present invention is to overcome the abovementioned drawbacks, by providing a shirt ironing apparatus, for industrial use, which is specifically designed to reduce the shirt ironing time to a minimum.
Within the scope of the above aim, a main object of the present invention is to provide a shirt ironing apparatus, for industrial use, which is adapted to simultaneously iron the body and shoulder portions of the shirts.
Another object of the present invention is to provide such a shirt ironing apparatus for industrial use, which also comprises a device for automatically take up an ironed shirt from its supporting dummy.
According to one aspect of the present invention, the above mentioned aim and objects, as well as yet other objects, which will become more apparent hereinafter, are achieved by an apparatus for automatically and simultaneously ironing shirt front, rear and top portions, characterized in that said apparatus essentially comprises two vertically extending cooperating ironing plate adapted to be driven towards one another, therebetween there is arranged a dummy bearing a shirt to be ironed and a top portion of which is adapted to be upward driven, said two plates defining, at a top portion thereof, two concave seats, one of which extends from an intermediate discontinuous portion, said concave seats defining a negative profile of the top portion of said dummy, means being moreover provided for gripping and transferring an ironed shirt.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the ironing apparatus according to the present invention will become more apparent from the following detailed description of a preferred embodiment thereof, which is illustrated, by way of a merely indicative example, in the figures of the accompanying drawings, where:
FIG. 1 is a schematic cross-section view of the dummy and two ironing plates included in the ironing apparatus according to the invention;
FIG. 2 is a top perspective view of the dummy, the ironing plates being arranged at a position removed from said dummy;
FIG. 3 is a cross-sectional view of a structure provided for slidably supporting the dummy;
FIG. 4 is a perspective view showing the dummy supporting structure;
FIGS. 5, 6 and 7 show a possible ironing procedure for ironing a shirt by the apparatus according to the invention;
FIG. 8 shows elements for gripping and transferring an ironed shirt;
FIG. 9 schematically illustrates a driving path of an arm element bearing the above mentioned shirt gripping elements;
FIG. 10 shows a device for driving the above mentioned arm; and
FIG. 11 shows a perspective view illustrating a top portion of the ironing apparatus according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the figures of the accompanying drawings, the apparatus for automatically ironing shirts according to the present invention essentially comprises two vertical parallel ironing plates 1 and 1' which can be driven toward one another by suitable driving elements.
More specifically, these two plates have top portions thereof, indicated respectively at 2 and 2', which have a concave profile adapted to mate with the profile of the corresponding top portions of the dummy 3 supporting a shirt 4 to be ironed.
In this connection it should be pointed out that the mentioned dummy is supported by a shaped plate 5 and that its top portion 3' is adapted to be upward driven by a rod 6 which is resiliently biassed, said rod being operated by a pressing cylinder 7.
It should be moreover pointed out that the dummy is hollow and communicates with a sucking duct 8 provided for always holding the dummy under a negative pressure so as to cause the shirt to suitably adhere to the outer surface of the dummy.
The dummy is moreover provided, at the top thereof, with a restraining element 9, for restraining the neck portion 4' of the shirt and with an opposite cylinder pair 10 and 10'.
These cylinders are provided for reciprocating corresponding rods 11 and 11' which can be introduced into the sleeves 4" of the shirt so as to hold these sleeves separated from the shirt body during the shirt ironing operation.
In one of the mentioned ironing plates, in particular, there is formed, at the dummy portion bearing the restraining element, an interruption 12 of half-round profile.
The dummy supporting plate 5 bears, at the bottom thereof, a pair of fork elements 13, provided with corresponding roller pairs 14 which can slide along the two sides of a first horizontal track 15.
The supporting plate, moreover, downward extends, by a doubly-bent portion 16 which supports two grooved rollers 17, which can slide on a second horizontal track or rail 18 provided for supporting the assembly.
The transfer of the dummy bearing thereon a shirt to be ironed, arranged between the two ironing plates, is performed by a double-acting cylinder 19 the rod of which is articulated to the above mentioned supporting plate.
Advantageously, the apparatus according to the invention further comprises a rail double pair (as is clearly shown in FIG. 4) extending according to converging paths toward the ironing plates.
Thus, owing to this provision, as one of the dummy bearing a shirt to be ironed is arranged between the two ironing plates, the other dummy can be easily fitted with another shirt to be ironed.
In operation, as is shown in FIG. 5, the dummy is displaced between the ironing plates which are driven toward one another so as to contact the shirt by a light pressure.
Simultaneously, there are actuated the side inflatable elements of the dummy so as to suitably spread the side portions of the shirt to be ironed.
Then (as is shown in FIG. 6), the plates 1 and 1' are forcedly closed so as to lock the dummy (with the exception of the top portion thereof) and the shirt.
Then, (see FIG. 7), the top portion 3' of the dummy, operated by the rod 6, is upward pushed so as to spread and press the shirt shoulder portions on said plates.
The ironing apparatus according to the present invention further comprises a device for removing from the dummy the ironed shirt, after having suitable moved away from one another the two plates and having opened the shirt neck restraining element 9.
In particular, this shirt removing or gripping device comprises a pair of pliers or grippers 20 mounted at the end portions of a tubular element 21 which is rotatably coupled to a supporting element 22 and bears rigid therewith a gear wheel 23.
This supporting element is firmly restrained to an arm 24, supported on a shaft 25, which is adapted to rotatively reciprocate into the two directions, by means of a driving reducing unit 26.
Coaxially with respect to the mentioned shaft there is provided a fixed supporting element 27 therewith there is rigid a further gear wheel 28 which, together with the first mentioned gear wheel, supports a chain 29.
Thus, as the above mentioned arm is turned either in one or in the other direction, in order to grip and remove the ironed shirt, by means of the pliers 20, it will cause the tubular element 21 to correspondingly turn so as to always hold the pliers in a vertical arrangement (see FIG. 9).
From the above disclosure and the figures of the accompanying drawings it should be apparent that the invention fully achieves the intended aim and objects.
While the invention has been disclosed and illustrated with reference to a preferred embodiment thereof, it should be apparent that the disclosed embodiment is susceptible to several modifications and variations, all of which will come within the spirit and scope of the appended claims.
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An apparatus for automatically and simultaneously ironing front, rear and top portions of a shirt comprises two vertical movable ironing plates therebetween there is provided a dummy bearing a shirt to be ironed, the dummy including an upwardly movable top portion and the ironing plates having two concave top seats negatively reproducing the profile of the top of the dummy, the apparatus further comprising gripping elements to automatically grip and transfer the ironed shirt.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of the priority date of U.S. Provisional patent application Ser. No. 61/792,514 filed Mar. 15, 2013, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
[0002] This invention relates to preventing ice buildup in fluid transport pipes. More particularly, the invention relates to providing a heating a fluid to warm a fluid inside of large pipes.
BACKGROUND OF THE INVENTION
[0003] In particular climates it is desired to heat, thaw and prevent the freezing of pipelines. The pipelines are used to transfer fluids across a distance, sometimes through areas of cold weather.
[0004] Presently, heat exchangers are used to keep the fluid in the pipeline from freezing. However, heat exchangers require that the fluid in the pipeline be flowing in order to be effective. Once the fluid stops moving, the heat exchanger is unable to heat the fluid thereby making the system ineffective.
[0005] Another method to heat fluid in a pipeline is to heat the exterior. This requires the installation of heated lines on the exterior surface of the pipe. However, these transfer lines are generally inefficient as much of the heat is lost to the ambient air.
[0006] Yet another method, is to insert a device into the line and use a vacuum to draw the fluid from the line. Once drained the fluid is heated and pumped back into the pipeline. This method is both very labor intensive and requires the special equipment such as vacuum trucks.
[0007] Therefore, a system for keeping high volumes of fluid from freezing is desired.
[0008] Further, a system for keeping fluids from freezing with minimal intervention (disassembly of pipelines, draining and down time) is desired.
[0009] Even further, a system to provide safe, continuous heat over long distances, and to easily and quickly thaw frozen pipe is desired.
SUMMARY OF THE INVENTION
[0010] In one form the invention relates to a fluid heating system having a pipeline having a heating insert installed along the length of the pipeline. The heating insert having at least one connector being in communication with a heating line, the heating line being positioned within the diameter of the pipeline. Heated fluid passes through the connector and through the heating line to warm the fluid within the pipeline.
[0011] In another embodiment, the invention includes a fluid heating system with a pipeline having at least one heating line located within its inner diameter. A heating insert delivers heated fluid to the heating line through a connector, while another connector receives heating fluid returning from the heating line.
[0012] In yet another embodiment, the invention includes a fluid heating system with a pipeline having a first opening, a second opening, a first pipeline flange, a second pipeline flange and an inner diameter. A heating insert is connected to the pipeline and has an outer surface, an inner diameter, an opening on each end, two heating insert flanges, at least two connectors passing through the outer surface of the heating insert, at least one heating line, wherein the heating line has a proximal end, a distal end, and both an inlet and an outlet near the proximal end. The first and second pipeline flanges are attached to the two heating insert flanges to form a continuous pipe as between said pipeline and said heating insert. The at least one heating line resides within the continuous pipe of the pipeline. The proximal end of the at least one heating line is connected to two connectors of the heating insert, and its distal end terminates within an inside diameter of the pipeline. The heating line is connected to the two connectors to form a continuous heating line as between one of the connectors of the heating insert, the heating line itself, and the other connector.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The present invention is disclosed with reference to the accompanying drawings, wherein:
[0014] FIG. 1 is an expanded isometric view of a pipeline having a heating insert and heated fluid lines according to one embodiment;
[0015] FIG. 2 is a close up isometric view of the heating insert shown in FIG. 1 ;
[0016] FIG. 3 is an alternative isometric view of the heating insert shown in FIG. 1 ;
[0017] FIG. 4 is an interior view of the heating insert shown in FIG. 2 ;
[0018] FIG. 5 is an expanded isometric view of a pipeline having a heating insert and heated fluid lines according to another embodiment;
[0019] FIG. 6 is a close up isometric view of the heating insert shown in FIG. 5 ; and
[0020] FIG. 7 is a close up isometric view of the heating line shown in FIG. 5 .
[0021] Corresponding reference characters indicate corresponding parts throughout the several views. The examples set out herein illustrates several embodiments of the invention but should not be construed as limiting the scope of the invention in any manner.
DETAILED DESCRIPTION
[0022] Referring to FIGS. 1-4 , there is shown the heating lines for integration with fluid pipes according to one embodiment. To heat the fluid in the pipeline 10 , a heating insert 20 is connected between sections of pipeline to allow integration of the heating lines 30 . Heated fluid enters through one of the connectors 23 and flows through a heating line 30 , such as a pipe, before exiting through a connector on a second heating insert (not shown), constructed similarly as the heating insert 20 . Thus, the heating line 30 is connected between two interior connectors 25 , one at each of two heating inserts 20 connected inline into the same pipeline 10 . As shown in FIG. 1 , more than one heating line 30 may be so connected as between two heating inserts 20 each having more than one interior connector 25 . Also as shown in FIG. 1 , each heating insert 20 may include upstream and downstream facing interior connectors 25 matching additional heating inserts 20 connected inline into the pipeline 10 upstream and downstream from the heating insert 20 illustrated in FIG. 1 . In one embodiment, a terminal heating insert 20 may include only an upstream or a downstream set of interior connectors 25 . In yet another embodiment, each heating insert 20 may include only one upstream and one downstream interior connector 25 , or only one of an upstream or downstream interior connector 25 . As illustrated in FIG. 4 , the heating insert 20 includes two connector pairs wherein one pair faces in one direction at a proximal end of the heating insert 20 and the other pair of interior connector 25 faces toward an opposite direction at a distal end of the heating insert 20 . Either of these interior connector pairs may be connected as upstream or downstream connectors. The heating insert 20 itself is a pipe having connectors formed therein and may be referred to herein as a pipe or pipeline. Hence, both the heating insert 20 and the pipeline 10 are each shaped as cylinders and each include a longitudinal axis along their cylindrical centers which may be considered to be coaxial when the heating insert 20 is attached to the pipeline 10 .
[0023] The heating insert 20 is connected in line with the pipeline 10 . The pipeline flange 11 is the same diameter as the heating insert flange 21 . The two flanges are connected together in a similar manner as connecting sections of pipeline, to form a leak-resistant seal and a continuous pipeline. This connection allows the flow of fluid through the pipeline and heating insert sections.
[0024] The heating insert 20 has at least one of connector 23 to allow transfer of heating fluid from the exterior of the pipeline into the interior of the pipeline without leaking heating fluid into the pipeline product itself. The connectors may be either inlet or outlet ports. It is understood that the heating insert may contain any number of connectors. In one embodiment, the heating insert has one inlet and one outlet connector. In another embodiment, the heating insert has two inlet and two outlet connectors. In yet another embodiment a first heating insert has one inlet port while a second heating insert has one outlet port. The connectors 23 pass through the heating insert 20 at the transition point 22 forming a closed loop that allows the connector to transfer fluid from the outside of the pipe to the heating line inside of the pipe and back out of the pipe through another connector. In one embodiment, the connector 23 further contains a shut off valve 24 to adjust or shut off the flow of heating fluid.
[0025] The interior connections 25 connect to the heating line connection 31 of the heating line 30 . heating fluid flows through the connector 23 through the heating line 30 to a second connector (not shown) before exiting the system. In one embodiment, an auxiliary pump is used to increase, or provide an adequate flow rate of the heating fluid.
[0026] In another embodiment, the connectors are integrated directly into the pipeline 10 , without the need for the additional heating insert 20 . While the heating insert 20 allows for integration into existing pipelines, a pipeline with integrated connectors and heating lines is ideal for a new build.
[0027] In use, the multiple heating inserts are connected between sections of pipeline. The heating insert attaches to the pipeline in the same manner as connecting multiple pieces of pipeline to form a continuous pipe. Inside the pipeline resides at least one heating line to carry heating fluid through the pipeline. The heating fluid is completely contained within the heating line to prevent the heating fluid from mixing with the fluid in the pipeline. Each end of the heating line connects to connectors found on the heating inserts connected to each end of the pipeline. These connectors allow the heating fluid to be transferred from outside of the pipeline and into the heating line found inside the pipeline when the pipeline is fully assembled and closed. By the heating line residing inside of the pipeline a more efficient level of heat transfer can be obtained.
[0028] Referring to FIGS. 5-7 , there is shown heating lines for integration with fluid pipes according to another embodiment. To heat the fluid in the pipeline 110 , a second embodiment of a heating insert 120 is connected between sections of pipeline to allow integration of the heating lines 130 . Heated fluid enters through one of the connectors 123 and flows through a heating line 130 before exiting another connector 126 on the heating insert 120 . While the description below will describe operation of the heating insert 120 embodiment of FIGS. 5-6 , it should be noted that the heating insert 20 shown in FIGS. 1-4 may also be used, with interior connections 25 therein for connecting to the heating line inflow and outflow connections 131 , 132 , respectively. The pipeline 110 of FIG. 5 is shown in a cutaway view to better illustrate the heating line 130 within the inside diameter of pipe 110 .
[0029] The heating insert 120 is connected in line with the pipeline 110 . The pipeline flange 111 is the same diameter as the heating insert flange 121 . The two flanges are connected together in a similar manner as connecting sections of pipeline, to form a leak-resistant seal and a continuous pipeline. This connection allows the flow of fluid through the pipeline and the heating insert.
[0030] The heating insert 120 has at least one of connector 123 to allow transfer of heating fluid from the exterior of the pipeline into the interior of the pipeline without leaking heating fluid into the pipeline product itself. The heating insert 120 also has at least one of connector 126 to allow return transfer of heating fluid from the interior of the pipeline 110 to the exterior of the pipeline without leaking heating fluid into the pipeline product itself. The connectors 123 , 126 may be arranged as either inlet or outlet ports. It is understood that the heating insert may contain any number of connectors. In one embodiment, the heating insert has one inlet connector 123 and one outlet connector 126 . In another embodiment, the heating insert has two inlet and two outlet connectors. The connectors 123 , 126 pass through the heating insert 120 at the transition point 122 forming a closed loop that allows the connector 123 to transfer fluid from the outside of the pipe to the heating line inside of the pipe and back out of the pipe through another connector 126 . The connectors 123 , 126 may further each contain a shut off valve (such as 24 as shown in FIGS. 1-4 ) to adjust or shut off the flow of heating fluid.
[0031] The interior connections 125 connect to the heating line inflow and outflow connections 131 , 132 , located near a proximal end of the heating line 130 . Heating fluid flows through one connector 123 through the heating line inflow connection 131 , which is the open proximal end of the small diameter interior pipe 133 . The heating fluid flows through the small diameter pipe section 133 of the heating line 130 toward a distal end of the heating line, and returns via a return channel formed by the larger diameter pipe 134 to heating line outflow connection 132 , then to another connector 126 before exiting the system. In one embodiment, an auxiliary pump is used to increase, or provide an adequate flow rate of the heating fluid. In an exemplary embodiment, the smaller diameter pipe 133 is a one inch pipe, and the larger diameter pipe 134 is a two inch pipe.
[0032] The heating line 130 is formed by positioning the smaller diameter pipe 133 within an inside diameter of a larger pipe 134 . The proximal and distal ends of the larger diameter pipe 134 are closed off, or capped (distal end), so as not to permit the heating fluid to exit therefrom, except through fluid return outflow connection 132 , as described below. Both the proximal and distal ends of the smaller diameter pipe are open. The proximal open end of the smaller diameter pipe 133 forms the heating line inflow connection 131 while the open distal end of the smaller diameter pipe 133 is positioned within the larger diameter pipe 134 and extends toward the closed distal end of the large diameter pipe. The open distal end of the smaller pipe does not make contact with the closed distal end of the larger diameter pipe so as to permit the heating fluid to exit from the distal end of the smaller diameter pipe 133 . Pressure from the heating fluid exiting the open distal end of the smaller pipe 133 generates a return flow in the plenum formed between an outside surface of the smaller pipe 133 and the inside surface of the larger pipe 134 from the distal end of the heating line 130 back toward its proximal end. The proximal end of the larger pipe 134 is sealed against the smaller inner pipe 133 to prevent heating fluid from exiting therefrom. The proximal end of the larger pipe 134 includes an opening having a connector 132 attached thereto allowing the heating fluid to exit the heating line and for connecting to the interior connection 125 of the heating insert 120 . The return heating fluid thereby exits the pipeline through connector 126 . The distal end of the heating line may be propped against a bracket supported by an inside diameter of the pipeline 110 . Similarly, the distal end of the smaller pipe 133 may be propped against a bracket on an inside diameter of the larger pipe 134 .
[0033] The heating insert 120 may be connected to heating fluid supply in line with an upper flange 140 . The heating fluid supply flange 141 is the same diameter as the heating insert upper flange 140 . The two flanges are connected together in a similar manner as connecting the pipeline 110 to end flanges 121 of the heating insert 120 to form a leak-resistant seal and a continuous flow. A central axis of the flange 140 may be said to be substantially perpendicular to the longitudinal axis of the pipeline 110 , while an axis of the flange 121 may be said to be substantially coaxial with the longitudinal axis of the pipeline 110 when the heating insert 120 is attached to the pipeline 110 .
[0034] In another embodiment, the connectors are integrated directly into the pipeline 110 , without the need for the additional heating insert 120 . While the heating insert 120 allows for integration into existing pipelines, a pipeline with integrated connectors and heating lines is ideal for a new build.
[0035] The heating insert 120 attaches to the pipeline in the same manner as connecting multiple pieces of pipeline to form a continuous pipe. Inside the pipeline resides at least one heating line 130 to carry heating fluid through the pipeline. The heating fluid is completely contained within the heating line to prevent the heating fluid from mixing with the fluid in the pipeline. The connectors 131 , 132 of the heating line 130 are connected to interior connections 125 of connectors 123 , 126 found on the heating insert. These connectors allow the heating fluid to be transferred from outside of the pipeline and into the heating line found inside the pipeline when the pipeline is fully assembled and closed. By the heating line residing inside of the pipeline a more efficient level of heat transfer can be obtained.
[0036] While the invention has been described with reference to particular embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope of the invention.
[0037] Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope and spirit of the appended claims.
[0038] While the invention has been described with reference to particular embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the scope of the invention.
[0039] Therefore, it is intended that the invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope and spirit of the appended claims.
PARTS LIST
[0040] 10 pipeline
[0041] 11 pipeline flange
[0042] 20 heating insert
[0043] 21 heating insert flange
[0044] 22 transition point
[0045] 23 connectors
[0046] 24 shut off valve
[0047] 25 interior connections
[0048] 30 heating lines
[0049] 31 heating line connection
[0050] 110 pipeline
[0051] 111 pipeline flange
[0052] 120 heating insert
[0053] 121 heating insert flange
[0054] 122 transition point
[0055] 123 heating insert inflow connectors
[0056] 124 shut off valve
[0057] 125 interior connections
[0058] 126 heating insert outflow connectors
[0059] 130 heating lines
[0060] 131 heating line inflow connection
[0061] 132 heating line outflow connection
[0062] 133 heating line interior pipe
[0063] 134 heating line exterior pipe
[0064] 140 heating insert upper flange
[0065] 141 heating fluid supply flange
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A system for heating fluid lines to prevent freezing and ice build up. A heated fluid line is utilized within the pipeline to achieve improved thermal transfer.
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FIELD OF INVENTION
This invention relates to electronic amplifier systems for musical instruments which also provide specialized circuitry for enhancement of sound produced by a sole instrument.
PRIOR ART
Electronic amplifying circuitry specifically designed for musical instrument amplification is well known and in use. Further, such circuitry may include switchable features to modify or enhance the tone of an instrument, vibrato and reverberation being common examples. One way of modifying and distorting the tonal quality of audio frequency signals generated by musical instruments, is to overdrive an electron discharge device of one of the stages of an amplifier to provide a non-linear output. Such an arrangement is disclosed by the patent to DeRosa U.S. Pat. No. 2,315,248. A further teaching is provided by the patent to Jahns 3,973,461 who utilizes a cathode follower as the distortion stage to which the audio frequency signals are applied.
The tube utilized as the cathode follower is biased to normally operate in a linear mode at normal signal levels but is driven sufficiently hard to provide distortion at its output by increasing the signal level at its input and decreasing the signal level at its output in order to maintain a predetermined normal output level. The signals applied to the input of the distortion amplifier are also adjustably added to its output. However, if only clean, undistorted signals or only the distorted signals are selected to appear at the output by cutting out the other of the signals, the signal level at the output varies accordingly and must be adjusted at each selection in order to maintain a given output level.
BRIEF DESCRIPTION OF THE INVENTION AND OBJECTS
In my amplifying circuitry, a plural control configuration can be remotely switched into operation which, with its input and output level controls adjusted, will give greatly improved lead instrument tonality providing sustain and distortion characteristics which are now part of lead instrument expression in the popular and blues music millieu and which have been previously partially attainable only by exceeding the designed power parameters of the output stage in conventional amplifiers.
A double-pole-double-throw (DPDT) switching relay is operable by either a front panel switch or remote push button to select either the conventional amplification mode or to activate the lead drive circuitry. Following initial pre-amplifier and tone control circuitry and a volume control, signal output from a low impedance cathode follower stage is a relay selected to couple through a pre-amplifier output level control to the power amplifier driver stage for conventional amplifying purposes. In the lead mode (with the relay activated) a signal from the low impedance source is instead coupled through a separate lead drive control into an additional high gain amplifying stage. The output level of this stage is regulated by a final control or lead master. The overall amplifier gain in the lead mode can be up to 50 or more times the amplification factor of the circuit in the conventional mode. This provides massive saturation of the lead drive and/or successive stages to generate a composite signal where as much as half or more of the signal content may be distortion products (mostly of the even harmonic order together with a substantial amount of the odd harmonics). With the added gain, string vibration at the instrument (electric guitar) may decay by 90% or more without effectively changing the tone of the volume produced by the circuit (the resulting musical tone sounds not so much like a plucked string as a bowed string.) The lead drive control regulates the amount of distortion and sustain; the lead master attenuates the output level so that the playing loudness in the lead mode is separately adjustable from the playing loudness in the conventional rhythm mode.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic circuit diagram of a basic embodiment of this invention;
FIG. 2 is a schematic circuit diagram of another embodiment of the invention using high voltage field effect transistors in the first two stages;
FIG. 3 is a schematic circuit diagram identical to that of FIG. 2 except that the direct coupled cathode follower stage V4 has been omitted;
FIG. 4 is a schematic circuit diagram showing a modified arrangement of the circuit elements enabling reverberation to be added to the amplifier; and
FIG. 5 is a schematic diagram showing another feature of my invention, namely the power supply circuitry for the relay, including local and remote switching features and a status indicator showing which mode of amplifier operation is currently selected.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
My improved dual mode music instrument amplifier circuit is shown in the drawings as utilizing triodes, identified as V1, V2, V3, V4 and V5 for the plural stages of the amplifier. It will be understood however, that any multi-element vacuum tube or semi-conductor may be utilized for this purpose.
In. FIG. 1 the input circuit is evidenced by the conductor 1, leading to the grid 11, of V1. The grid leak resistor 7, connects to the common 99, which is grounded at ground 100. The amplifier stage V1 is conventionally arranged with the cathode bias resistor 8 and bypass capacitor 9 between the cathode 10 and common 99. The plate 12 of V1 is connected to the B+DC high voltage supply 92 through load resistor 13. Amplified output from V1 is fed by conductor 70 to the tone control network comprising components 14 through 23 and component 68. The treble control 16, is in a tee formation. The treble RC network consists of the potentiometer 16 and the capacitor 14. Treble control center point frequency shift can be accomplished by means of the switch 68' (called treble shift), which introduces more capacitance 15 into the RC network. Potentiometer 19 is the base tone control and works in conjunction with capacitor 18. Potentiometer 21 is the middle frequency tone control whose RC network includes capacitor 20. Resistor 17 is used to obtain a balance in the outputs of the base and middle RC networks relative to the output of the treble RC network. SPST switch 22 deactivates the tone control network when open and, as this eliminates a substantial loss of gain caused by the tone control network, the switch is called the gain boost. Resistor 23 conducts the signal to potentiometer 24, known as the Volume 1 control. The resistor 23 prevents loading of the tone control circuit when Volume 1 (24) is set low. The bright switch 26 activates capacitor 25 to compensate for treble frequency attenuation at low settings of Volume 1 (24). V2 is another conventional amplifier stage. Its grid 27 receives the signal from the control 24 (and possibly from the bright switch) via conductor 71. The cathode 30 of V2 is biased by resistor 28 and bypassed by capacitor 29. The plate 31 of V2 is fed from the B+ supply through load resistor 32. The blocking capacitor 33 couples the output of V2 to the grid 36 of V3 through an RC network used for tone shaping comprising resistor 34 and capacitor 35. Resistor 37 serves as the grid leak for V3. The V3 cathode 40, is also conventionally biased through resistor 38 and bypassed to ground via capacitor 39. Plate 42 is connected to B+ supply 90 through load resistor 41. The signal output of V3 is direct coupled to the grid 44 of stage V4 by a conductor 43. The plate 47 of V4 is connected directly to the B+ supply by conductor 72. The cathode 45 is biased by resistor 46 and the output of the V4 cathode follower stage is coupled via capacitor 48 and resistor 49 to the first pole 50 of the DPDT status relay. It should be noted at this point that the cathode follower stage V4 contributes only a slight enhancement of musical characteristics and may be omitted without severely affecting the overall performance of this preamplifier. Such a circuit is shown in FIG. 3. The first segment of the DPDT relay consists of input contact pole 50 and output contact throws 51 and 69 which perform half of the selection between normal and lead amplification modes. In this normal (relay de-activated) position, a signal is conducted by the relay from point 50 to point 51. Resistor 52 couples the signal into potentiometer 53 which is the Master 1 control. Output from this control reaches contact 55 of the second segment of the DPDT relay via conductor 54. As shown in the drawings, the pole segments of the status relay are coordinated so that the signal is conducted to the pre-amplifier output termination 57 via relay contacts 55 and 56 when the signal is present at Master 1 control 53, as selected by contacts 50 and 51 of the preceding relay segment. Thus, the amplifier circuit comprising V1, V2, V3 and V4 can be adjusted via the Volume 1 control 24, and the Master 1 control 53 to furnish an appropriate amount of gain to the power amplifier to which the signals are applied to allow normal and faithful amplification of an electric musical instrument. Distortion is low and the output sound develops a musical richness due to the processing it receives and due to the plurality of stages, even in the rhythm mode, as V1 and V2 alone are easily capable of supplying sufficient drive to most power amplifier circuits.
When the relay is activated (relay position shown by dashed lines), the amplifier is switched into the sole mode primarily by the inclusion of V5. When activated, the relay conducts a signal from the output of V4 across the points 50 and 69 to a potentiometer 80 known as the lead drive. The lead drive 80 controls the amount of signal arriving at the grid 66 of V5. This signal voltage can be many times the allowable headroom or grid driving voltage of V5 so that the lead drive control 80 adjusts the amount of saturation overdrive, and hence the added harmonic distortion content typical of the desired lead solo sound. V5 is operated as a conventional plate loaded amplifier, and is biased to operate about the midpoint of the linear portion of its characteristic. The signals applied to its grid from the perceding amplifier stage are of such large amplitude that both the positive and negative excursions thereof drive the tube to operate in the non-linear portions of its characteristic. There is thus obtained at its output distorted signals rich in both even and odd harmonics. Its cathode 65 is biased by resistor 63 and is bypassed to ground by capacitor 64. Load resistor 58 connnects the plate 59 with the B+ supply 90. Output is taken from the plate and coupled by capacitor 60 to a potentiometer 61, known as the lead master. The lead master potentiometer 61 operates to control the overall system loudness in the lead or solo mode of operation and this attenuated output appears at the pre-amplifier termination 57 after being conducted across the relay contact points 62 to 56. Resistor 91 is used in the B+ supply line to lower the voltage slightly for the field effect transistor drain elements where they are used (as in FIG. 2), and to decouple these input stages from the following stages. Capacitor 93 is an electrolytic filter type which completes the decoupling and prevents oscillation to high gain settings.
This adaptation of the circuit in FIG. 1 is designed and constructed such that the active elements of V1 and V2 can be either dual triode vacuum tubes or high voltage field effect transistors which are available as dual units in a nine-pin plug-in package, and are directly interchangeable with the tube. It should be further understood that field effect transistors could be substituted in a similar fashion in any or all of the amplifier stages and also that NPN or PNP bipolar transistors could be employed in a switchable circuit using the same overdrive principles, although the harmonic distortion products of this device is less well suited.
FIG. 2 shows an adaptation of the circuit which allows the use of field effect transistors in the first two stages, V1 and V2. This modification, as noted, allows for direct plug-in replacement of the dual triode electron tube by the properly packaged dual high voltage FET and, similarly, in case of damage or failue, the FET may be replaced by a conventional dual triode. This direct interchangeability of vacuum tube and solid state devices in the critical input stages constitutes another embodiment of my invention. It should be noted that the dual mode and overdrive saturation principles of my invention could be achieved by any combination of vacuum tubes, FETs, or bipolar transistors at V1,V2,V3,V4 and V5. The electron tube elements labeled in FIG. 1 have their equivalent counterparts in the FET elements of FIG. 2; i.e. for V1 the grid 11 is counter to gate 73, cathode 10 is counter to source 74, plate 12 is counter to drain 75, and similarly for V2 the gride 27 is counter to gate 76, cathode 30 is counter to source 77, and plate 31 is counter to drain 78. Deviations from the circuit diagram of FIG. 1 are the constant current course diodes (element 67 for V1, element 68 for V2) which regulate bias and therefore maintain operational stability for the FETs over a wide range of temperature, and further prevent drift from FET aging. These are bypassed to ground by the same capacitors 9 and 29 which appear in FIG. 1. The other deviations of FIG. 2 from FIG. 1 constitute the input protection system required by the FET comprising parts 2 through 6. The resistors 2 and 3 comprise a voltage divider to protect senser diodes 4 and 5 from burn out in the event a high voltage high power signal is applied to the pre-amplifier input turning the zeners on into conduction. The zener diodes themselves, 4 and 5, limit the amount of voltage which can appear at the FET gate to a predetermined level and prevent damage of the FET due to ground loops or misuse of the amplifier. Capacitor 6 further protects the FET by blocking any DC leakage which may appear superimposed on the input signal.
FIG. 3 shows another embodiment of the circuits shown in FIG. 1 and FIG. 2, namely omission of the cathode follower stage V4. As previously noted, this omission does not substantially alter the principle or performance of the pre-amplifier, and may be justified economically in circumstances which would require the addition of another tube, socket, shield and peripheral wiring for its inclusion. If an otherwise unused triode is available (as may be the case where reverberation is added to the pre-amplifier) the inclusion of the V4 cathode follower to the circuit makes the output of my pre-amplifier slightly smoother sounding in the lead mode and somewhat richer sounding musically in the conventional amplifying mode of operation. The circuit of FIG. 3 shows the coupling capacitor 48 connected to the plate of V3 instead of the cathode of V4 as in FIG. 2. Otherwise the circuits of FIG. 2 and FIG. 3 are identical.
FIG. 4 is a schematic diagram which shows the dual mode music instrument pre-amplifier with the addition of reverberation. This entails a somewhat different arrangement of the same basic circuit elements as previously described in order to maintain a proper reverberation function in both solo and rhythm modes of operation. Up until the output of the V2 stage, the circuit is identical with that described and shown in FIG. 2, and it will be further seen that many other elements of the FIG. 2 circuit appear here in FIG. 4 with the same functions as performed previously although the sequence of the stages and the function of the relay vary somewhat. The output of the V2 amplifier stage, then, is coupled by capacitor 33 to a junction point 400. Here a signal is coupled to the V3 grid 36 through the familiar RC network comprising resistor 34 and capacitor 35. Also fed from the junction point 400 are the overdrive stage V5' and the reverberation drive stage V6, V7. Capacitor 402 and resistor 401 couple the signal from point 400 to the grid 66 of V5'. The lead drive control 80 attenuates the signal and hence overdrive distortion produced by the V5' amplifying stage. Circuit components, 58, 59, 60, 63, 64, 65 and 66 of V5' remain identical to those as described under FIG. 2. The relay, however, is arranged differently. The center pole 403 of one relay segment is connected to ground 100. In the rhythm mode of operation, the V5' overdrive stage is de-activated by virture of its signal being shunted to ground via the relay from contact 404. The low gain signal is conducted from junction 400 to the grid 36 of stage V3 by the RC network comprising resistor 34 and capacitor 35. Resistor 434 reduces loading at the grid 36 of V3 to a neglibible amount when the amplifier is in the rhythm mode and the output signal of V5' is shorted to ground. When the relay is activated (shown by dashed lines) the ground shunt is removed, allowing the adjustable high gain output of V5' and its Class A triode distortion products to be coupled into the grid 36 of V3 by resistor 434. V3 and its associated circuit parts are identical in description and operation to those of V3 in FIG. 2. The output of the V3 amplifier is direct coupled to V4, again, exactly as previously described under FIG. 2. The low impedance cathode follower output of V4 is coupled by capacitor 48 and resistor 49 to the Master 1 control 53. The output of the Master 1 control constitutes the final amplifier output 57 as in FIG. 2. For the sake of clarity, consider that the amplifier output 57 is common with (or connected to) a junction point 435. Also tied to this output junction point 435, 57 is the wiper or adjustable leg of the lead master control 61. When the mode selecting relay is activated (dashed lines) and the ground shunt is removed from the output of V5', that same ground shunt 403, 100 is applied to one end of the lead master potentiometer 61 via relay contacts 405 and 403. This ground shunt activates the lead master control 61, causing it to override the master 1 control 53 and allowing a pre-settable attenuation of the now boosted amplifier output as it arrives at the output junction 435, 57 from cathode follower stage V4. An additional feature is a high-frequency-cut switch 437 which bypasses upper treble and harmonics to ground through capacitor 438. A virtue of this high-cut switch is that it has no effect on the rhythm signal tonality because capacitor 438 can only drain to ground when the relay is selecting the lead mode of operation. Therefore, if the musician wishes to select a bright, treble chording sound, he can prevent his lead tone from being too bright and thin by the use of the high-cut switch 437.
From the junction point 400, the signal is also coupled into the reverberation driver amplifier V6-V7 through capacitor 407 and mixing/isolation resistor 406. The reverberation driver amplifier shown is a dual-parallel-triode transformer coupled Class A output amplifier comprising V6, V7 and associated components. The grids 410, 411 use resistor 408 for grid leak to ground 100. The two cathodes 412, 413 are biased by resistor 415 and bypassed by capacitor 414 to ground 100. The two cathodes 412, 413 are biased by resistor 415 and bypassed by capacitor 414 to ground 100. The plates 408, 409 are connected through the primary winding 416 of a small output transformer to the B+ high voltage 439. Spurious oscillation is eliminated by neutralizing capacitor 440 between the plates 408, 409 and the cathodes 412, 413. The secondary winding 417 of the output transformer couples the signal into a three-spring electro-mechanical reverberation delay line 418. The grid 420 of the reverberation return pre-amplifier V8 is fed from the output of the spring delay line 418 and uses for grid leak a resistor 419 connected to ground 100. V8 is a conventional high gain Class A amplifier whose cathode 421 is biased by resistor 423 and bypassed by capacitor 422. A plate load resistor 425 connects the V8 plate 424 to the B+ voltage supply 90. Amplified reverberated signal is taken from the plate 424 of V8 through coupling capacitor 426 to one end of the reverb intensity control 427, the other end of this control being grounded. The adjustable reverberation signal is taken from the variable leg of the reverberation control 427 and fed to the remaining segment of the DPDT relay via conductor 428. This segment of the relay, comprising input pole 429 and output contacts 430 and 432 assigns the reverberated signal to the appropriate circuit points so that a proper ratio of reverberated and real-time signals is maintained in both modes of amplifier operation. With the amplifier in the rhythm mode (as shown) the reverberation signal is conducted across relay points 429 to 430 and through mixing/isolation resistor 439 where it joins with the low gain signal from the RC network of 34 and 35 to feed the grid 36 of V3. When the relay is activated (dashed lines) and the amplifier is in the lead mode, the reverberation signal is instead conducted across relay points 429 to 432 and through mixing/isolation resistor 433 to the grid of the now activated V5' overdrive amplifier. Thus, as the real-time signal is processed by the V5' stage and may attain up to another 50 or more times amplification, the reverberated signal is likewise amplified so that a fairly constant amount of reverberation is maintained in both modes of amplifier operation.
The relative location of the switchable overdrive stage V5 has been changed to accommodate proper mixing of the reverberation (delay/decay) signal in both solo and rhythm modes of operation and has been identified as V5'. In the circuit of FIG. 4, it will be seen that one segment of the DPDT control relay is used to switch in the plural control overdrive stage V5', while the other segment is used to assign amplified signal returning from the reverberation delay line. This output from the reverberation system remains constant whether the amplifier is in the rhythm or lead mode, and in order to maintain a proper ratio of real-time signal to reverberation delay signal in both modes. Output from the reverberation circuit must be mixed into the overdrive stage V5' when the relay is activated and the lead mode selected.
FIG. 5 is a schematic diagram showing an embodiment of this invention, namely the relay power supply and switching system which enables the amplifier to change back and forth between conventional amplification and the lead mode operation. In this diagram, the power transformer 98, has a 6.3 volt filament winding 101, with a center tap 97, connected to a common ground 99, 100. Vacuum tube filaments are represented at 102 and 103, and there may be several. A silicon diode 104 rectifies one leg of the AC line during its positive half-cycle. An electrolytic capacitor 105 stores energy while the diode 104 conducts and also passes voltage to a common point 120 when the other leg of the AC line goes positive and the diode is momentarily shut off. Resistor 106 limits the amount of current which can be drawn by the relay activation coil 107. Another electrolytic capacitor 108 shunts transients to ground and prevents audible popping noise in the amplifier when the relay is tripped. A single-pole-single-throw switch 109 is located on the amplifier front panel for local relay control and as a fail-safe. A pair of jacks 11 and 81 and plugs 112 and 82 allow connection of a cable 113 to a remote push-button SPST switch 110. An LED status indicator 115, mounted on the switch housing, is attached by a current limiting resistor 114 between the positive relay activating voltage and ground. When the switch 110 is closed, the relay voltage drops below the level needed to excite the LED.
In considering this invention, it should be remembered that the present disclosure is intended to be illustrative only and the scope of the invention should be determined by the appended claims.
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An electronic amplifying apparatus intended for electric music instruments (primarily guitar), with switchable circuitry offering an improved, specialized circuit for the enhancement of solo playing in addition to customary simple amplification. In the lead (or solo) mode of operation, the circuit will synthesize particular sustain and distortion characteristics and add them to the tone of the instrument (guitar, electric piano, microphone, etc.) to produce a more flexible and expressive sound for solo playing than the sound of the instrument normally amplified. Switching and control circuitry enable the musician to return to a conventional amplified tone which would be preferred for rhythm (or chordal) playing.
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FIELD OF THE INVENTION
The invention relates to a damper for pressure measuring systems, for monitoring the pressure in blood pressure measurements comprising a flow passage and a compartment in fluid communication with said passage.
For the continuous monitoring of arterial blood pressure, a pressure measuring system is often used which consists of a catheter introduced into a peripheral artery, a transmission line filled with a liquid, and a pressure sensor which converts the pressure at the end of the transmission line into a proportional electrical signal. This signal is then indicated on a screen or evaluated in some other manner.
The transmission of dynamically varying pressures in closed liquid circuits creates the problem of reflections occurring from the maladaption of the pressure sensor to the liquid column; these reflections distort the measurement. For example, a pressure wave propagated from the patient to the pressure sensor is not fully absorbed by the pressure sensor but instead partly reflected by the sensor and return at reduced amplitude towards the patient. At the patient, the reflection will again be reflected back towards the sensor due to maladaptation. These multireflected pressure waves give rise to heterodyne waves whose resonant frequency may lie near a lower order harmonic of the first harmonic oscillation or the first harmonic. This may entail significant distortion of the measurement signal which cannot be removed from the evaluation.
BACKGROUND OF THE INVENTION
It is known (U.S. Pat. Nos. 4,431,009 and 4,335,729) that the parasitic oscillations can be attenuated by providing dampers in the vicinity of the pressure sensor in parallel with the transmission line. The dampers absorb part of the high frequency components of the pressure signal thereby moderating the amplitude of the reflected oscillations.
The damper, according to U.S. Pat. No. 4,431,009, is embodied in an adjustable needle valve which represents a flow resistance that can be varied. The damper is arranged as a separate aggregate between the pressure measuring transformer and a three-way valve. This valve links the transmission line between the patient and the pressure sensor to an infusion means because in the majority of cases when blood pressure is continuously measured the transmission line is rinsed with an infusion solution. Finally, a check valve is also located in the transmission line so it can cut off the pressure sensor from the measuring system. This is required to adjust the pressure sensor to atmospheric pressure.
The damper, according to U.S. Pat. No. 4,335,729is likewise designed as a needle valve and is connected to a branch-off from the transmission line. It includes a sealed compartment totally surrounded by rigid walls and containing an air cushion to dampen the oscillations. The flow cross section of the connection between the transmission line and the compartment is regulated by the adjustable needle valve.
These dampers serve their purpose, however they are rather expensive for disposable items. Moreover, the additional adjustable component makes both measuring systems complex because they need to be continually adjusted. Finally, their structural design require the dampers to be mounted only at a certain distance from the pressure transducer so that their effect is not optimal.
German patent DE 24 05 584 responds to the problem of reflections in a system for the pulse-wise ejection of droplets by suppressing the reflected pressure wave with acoustic impedance matching through an elastic conduit.
German patent DE 29 41 118 shown a liquid spring damper comprising of two pot-like compartments which are supported "floatingly" with respect to each other by a shear spring. The two compartments communicate through a throttle. An elastic bellow is arranged inside the inner compartment and, as it is pressurized by adjustable gas pressure, it blocks the throttle at an appropriate gas pressure. The throttle does not open until the pressure n the main compartment exceeds that in the bellows. In this manner, a damper is provided which has a nonlinear characteristic and is adjustable by the pressure inside the bellows.
SUMMARY OF THE INVENTION
It is the object of the invention to improve the damper of the kind mentioned above so that it will have a more compact structure.
The present had the damper integrated in a valve insert or body of the valve. The flow passage through the valve insert communicates through a capillary bore with a compartment formed in the valve insert and closed off by a rubber-elastic diaphragm. The diaphragm is supported so that it can be deformed primarily only in the direction that enlarges the compartment. There is another compartment on the other side of the diaphragm remote from the first compartment. This second compartment is connected to the atmosphere through a nozzle or port thereby communicating with ambient pressure. The diameter of the second compartment is bigger than the first so that the diaphragm can be deformed in the desired direction only.
According to another variant of the invention, the movability of the diaphragm is limited, or even prevented altogether, by introducing a plunger into the second compartment. When it is in its one limited position, the plunger comes into contact with the diaphragm on its face end, and thereby blocks diaphragm movements. When the plunger is in any intermediate position, the maximum amplitude of deflection of the diaphragm will be limited and the volume of the second compartment will be varied.
The damper is preferably integrated in the valve insert of a three-way valve. However, it may also e integrated in other types of valves, such as a simple shutoff valve according to a modification of the invention.
BRIEF DESCRIPTION OF THE DRAWING
The invention will be described further, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a cross sectional view of the damper in the valve insert of a three-way valve according to a first embodiment of the invention;
FIG. 2 is a cross sectional view of a valve insert with damper according to a second embodiment of the invention;
FIG. 3 is a side elevational view of a three-way valve including an integrated damper; and
FIG. 4 is a top plan view of the valve shown in FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The three-way valve shown in FIG. 1 comprises a casing 1 which has three connecting ends 2, 3, 4 (cf. FIGS. 3 and 4) and in which a valve insert 5 (plug) is received. Depending on the rotary position of the valve insert passages 6 and to establish the valve insert flow connection between the various connecting ends 2, 3, and 4. In this respect, the valve is a conventional three-way valve.
A damper is integrated in the vale insert 5. To achieve this, passages 6 and 7 in valve insert 5 are in fluid communication through a capillary bore 8 with a first compartment 9. The first compartment is integrated in the valve insert and in the embodiment shown is of cylindrical shape. The face end of the first compartment 9 remote from the capillary bore 8 is closed by a rubber-elastic diaphragm 10. The rim of the diaphragm 10 is retained in an annular groove 11 presented in a widening handle 15 of the valve insert. The diameter of the diaphragm 10 is distinctly greater than the diameter of the cylindrical first compartment 9 so that considerable portions of the diaphragm edge lie on the face end of the wall which defines the first compartment 9. In this manner, the diaphragm 10 can be deform to a greater extend in the direction of enlarging the first compartment 9 than in the opposite direction.
The diaphragm 10 is retained by a cover 12 which is U-shaped in cross section and inserted in a recess formed in the handle 15. The shape of cover 12 together with the diaphragm 10 forms a second compartment 13. The diameter of the second compartment 13 is greater than that of the first compartment 9.
The cover 12 has a nozzle-like port 14 through which ambient or atmospheric pressure is admitted to the second compartment 13. The dimension of the port 14 is chosen so small that it presents flow resistance to the air which is exchanged between the compartment 13 and the surroundings upon deflection of the diaphragm.
In the embodiment illustrated in FIG. 2, the damper is adapted to be switched by a plunger 16. The plunger 16 is placed in the cover 12 and can be displaced in the axial direction. When the plunger is in one limited position it will contact the diaphragm, thereby preventing the diaphragm from oscillating. The diameter of the plunger corresponds approximately to the diameter of the first compartment 9, so that when it is in the limit position the face end of the plunger fully covers that area of the diaphragm 10 which closes the first compartment 9. In the embodiment shown, this plunger is threaded into the cover 12 by means of a thread 19 of relatively great pitch. A lever 17 is provided for actuation of the plunger 16. As an alternative, a vertical-horizontal lever an eccentric may be provided to selectively prevent deflections of the diaphragm. As the thread between the plunger 16 and the cover 12 is not absolutely tight, the function served by the port 14 in the embodiment according to FIG. 1 is fulfilled at the same time.
FIGS. 3 and 4 are presentations of a three-way valve with an integrated damper.
The valve with its damper may be secured by way of flanges directly to the measuring transformer (not shown) thereby offering a good damping characteristic throughout the measuring circuit. The collar 18 shown in FIGS. 1 and 2 at the valve insert serves to arrest the valve insert in the casing against any movement in axial direction.
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The damper for pressure measuring systems is integrated in the body (5) or insert of a valve. Flow passages (6, 7) communicate with a compartment (9) which is sealed by a rubber-elastic diaphragm (10). The side of the diaphragm remote from said compartment (9) defines a second compartment (13) which is connected to atmosphere through a port (14) designed to provide flow resistance.
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PRIORITY TO RELATED PATENT APPLICATION
This patent application is a Continuation-In-Part of U.S. patent application Ser. No. 11/271,067, which was filed on Nov. 10, 2005 now abandoned and is incorporated herein by reference in its entirety. U.S. patent application Ser. No. 11/271,067 in turn claims priority to International Patent Application No. PCT/AU2004/000681, entitled “A Swimming Pool Cleaning and Sanitising System,” which was filed under the Patent Cooperation Treaty (PCT) on May 21, 2004, and claims priority to Australian Patent Application No. 2003902540 filed in Australia on May 23, 2003, said applications expressly incorporated herein by reference in their entireties.
TECHNICAL FIELD
The present invention relates to swimming pools, spas & water features and in particular to a method and apparatus for improving the cleaning and sanitizing of the water contained in swimming pools, spas & water features.
BACKGROUND OF THE INVENTION
The cleaning and sterilization of swimming pools is currently accomplished using any one or more of mechanisms such as salt water chlorination or chlorine addition.
Chlorine is a strong bleach. It is dangerous. Side effects of its use can include red, irritated eyes, dried and brittle hair, and swimmers ear, bleached out swimsuits, dry itchy skin, and a clinging odor of chlorine.
Chlorine absorbs through the skin. Studies have linked chlorine with cancer, high blood pressure, anemia, heart disease, hardening of the arteries, senility, stroke and other degenerative diseases. Scientists have reported that chlorine is a leading cause for the erosion of the earth's ozone layer. It only occurs naturally safely wrapped up in compounds which are relatively unreactive.
Some of the problems associated with using chlorine have been discussed in literature sources such as:
1. Aggazzotti, G., Fantuzzi, G., Righi, E., & Predieri, G. (1998). Blood and breath analyses as biological indicators of exposure to trihalomethanes in indoor swimming pools. Science of the Total Environment, 217, 155-163. 2. Lindstrom, A. B., Pleil, J. D., & Berkoff, D. C. (1997). Alveolar breath sampling and analysis to assess trihalomethane exposures during competitive swimming training. Environmental Health Perspectives, 105(6), 636-642. And 3. Drobnic, F., Freixa, A., Casan, P., Sanchis, J., & Guardino, X. (1996). Assessment of chlorine exposure in swimmers during training. Medicine and Science in Sports and Exercise, 28(2), 271-274.
Salt water chlorination is a particularly popular technique in which salt (pure, natural rock salt) is dissolved in pool water and then subjected to simple electrolysis. This electrolysis usually takes place in an in-line electrolysis cell. The chloride portion of the salt (sodium chloride) is transformed during the electrolysis into an effective sanitizer, hypochlorous acid, (HOCl) which has the ability to oxidize (kill) bacteria, virus, algae and other such radicals which would otherwise flourish in the water. This process is reversible, so does not consume the salt, which is simply used over and over again.
HOCl is the same effective sanitizer as would result if ‘pool chlorine’ was added to the water—is utilised to minimise the potentially dangerous chlorine compounds and the obnoxious ‘chemical’ effects commonly associated with manual chlorination—and without the need to handle chemicals. It does not always achieve this aim.
Oxidation normally takes place in a swimming pool where the water and its associated contaminants are affected by a chemical oxidizer added to the water and used to oxidize oils and body fats. The chemical oxidizers increase the Oxidation Reduction Potential (ORP) of the water in the pool, but they also have their disadvantages. Oxidation Reduction Potential (ORP) is the extent to which a chemical ion exchanges electrons, which lead to electrical charges, during a chemical reaction.
Chemical oxidizers are quite expensive as they must be continually purchased and added to the water. They are also known to have serious health issues regarding toxicity of chemicals & proven toxic side effects of the by-products which include Chloramines, Triharlomethanes and Ozone.
Ionisation is an alternative method used in the sanitizing of swimming pools. Ionization produces copper ions (algaecide) and silver ions (bactericide) into the water flow of the swimming pools. Ionisation is not as effective as a stand-alone treatment for a swimming pool as it requires the addition of an oxidizer in order to be effective. One major benefit of ionization is its residual qualities. The copper and silver ions are not affected by heat or ultraviolet light and will remain in the water effective as a sanitizer for weeks after the system is shut down. Unlike chlorine and ozone, the copper/silver ions are not considered toxic at the levels required to sanitize the water.
The modern ioniser consists of two parts; the electrode assembly consisting of two (or multiples of two) bars of metal usually made of an alloy of copper and silver and the electronic control unit. The electrodes are usually installed in the swimming pool's filtration system. The control unit supplies the necessary extra low voltage across the electrodes. The resultant current produces positively charged ions of the constituent metals which are carried into the pool and become part of the chemistry of the pool water.
Silver ions act as a disinfectant and copper ions act as an algaecide. Although these ions kill algae and bacteria and provide a measurable residual quality, they do require an oxidiser to be present for the oxidation of organic wastes. Most manufacturers recommend the use of chlorine, but non-chlorine chemical oxidisers are also available.
Ozone is one of the most effective disinfectants and oxidisers available and once introduced into the water it starts to work immediately, killing bacteria and oxidising organic waste. As ozone is not highly soluble in water, the ozone must be injected into the water by either a compressor or venturi system.
However, as ozone is also toxic, all traces must be used or removed prior to a person using the pool. As there can be no residual of ozone when the pool is used, some other form of residual sanitiser like chlorine or bromine must also be used in order to provide continuous protection when the ozone generator is turned off.
Ultrasonics can also be used to clean surfaces remove existing scale, prevent scale formation and assist in sanitizing the water in the swimming pool by helping to break down the protective shell of most common parasitic organisms. Ultrasonic cleaning is a result of sound waves introduced into the water by means of a series of coils wrapped around a pipe that is part of the filtration circuit. The sound travels through the pipe carrying the water and creates waves of compression and expansion in the liquid. In the compression wave, the molecules of the fluid are compressed together tightly. Conversely, in the expansion wave, the molecules are forced apart, creating microscopic bubbles. The bubbles only exist for a split second and contain a partial vacuum while they exist.
As the pressure of the bubbles increases, the fluid around the bubble rushes in, collapsing the bubbles rapidly. When this occurs, a jet of liquid is created that may travel very quickly. They rise in temperature to as high as 5000 degrees Celsius. This extreme temperature, combined with the velocity of the liquid jet provides an intense cleaning action in a minute area. Due to the very short duration of the bubble expansion and collapse cycle, the liquid surrounding the bubble quickly absorbs the heat and the area cools quickly.
Potential problems in ultrasonic cleaning exist if the set point of any one or more of cleaning cycle time, temperature, chemistry, proximity to the transducer, ultrasonic output frequency, watts per liter or the volume of the liquid being cleaned is not correctly adjusted.
Traditional ultrasound technology is currently applied to the processing of low volumes and flow rates, typically in the range of 60-100 gallons per minute.
Each of the above systems has advantages and disadvantages. The inventors of the present invention have found that ionization on its own has an excellent residual but requires addition of an oxidizer, generally requiring the addition of chemicals or ozonation to prevent the build-up of debris on pool surfaces and the oxidization of oils and body fats.
Ultrasonics on its own will prevent the build-up of scale on pool surfaces and fitting and the reduction of parasitic growth.
Electronic Oxidization on its own would have to operate constantly to maintain the residual disinfection in the body of the pool water making it uneconomical in the domestic a commercial environment/
The inventors of the present invention found that the three processes working together complement each other and combine to be an excellent system in providing the required sanitizing processes without the addition of chemicals or ozone to achieve oxidization.
It will be clearly understood that, if a prior art publication is referred to herein; this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.
BRIEF SUMMARY
The following summary is provided to facilitate an understanding of some of the innovative features unique to the embodiments disclosed and is not intended to be a full description. A full appreciation of the various aspects of the embodiments can be gained by taking the entire specification, claims, drawings, and abstract as a whole.
It is, therefore, one aspect of the present invention to provide for a swimming pool cleaning and sanitation system.
The aforementioned aspects and other objectives and advantages can now be achieved as described herein. The present invention is directed to a swimming pool cleaning and sanitation system, which may at least partially overcome the abovementioned disadvantages or provide the consumer with a useful or commercial choice.
In one embodiment, the present invention can reside in an in-line cleaning and sanitation apparatus for cleaning a liquid contained in a body of liquid by removing a portion of the liquid from the body, cleaning and sanitizing the portion and returning the portion to the body, the apparatus comprising two or more two electrolytic cells, including an electrolytic ionization cell to produce ions having an algaecidal or bactericidal effect into the liquid, and an electrolytic oxidization cell to increase the oxidation reduction potential of the liquid; and an ultrasonic cleaning means to introduce sound waves into the liquid, wherein the two or more electrolytic cells are provided in the order of electrolytic oxidization cell, and electrolytic ionization cell and are operated simultaneously for a period to clean and sanitize the liquid in the absence of added salt, chlorine or other chemicals.
In another embodiment, the present invention can reside in a cleaning and sanitation method comprising the steps of providing electrolytic oxidation cell to increase the oxidation reduction potential of the liquid; providing an electrolytic ionization cell to produce ions having an algaecidal or bactericidal effect into the liquid, provided in that order; and providing an ultrasonic cleaning means to introduce sound waves into the liquid, and operating the electrolytic ionization cell, the ultrasonic cleaning means and the electrolytic oxidation cell simultaneously for a period to clean and sanitize the liquid without the addition of oxidation-promoting chemicals or ozone.
According to a particularly preferred embodiment, the ionization means may comprise two parts; an electrode assembly and an electronic control unit. The electrode assembly may preferably comprise two (or multiples of two) bars of metal, an anode and a cathode, at least one usually made of an alloy of copper and silver. According to a particularly preferred embodiment, the ionisation rods may each be an alloy of copper. A preferred composition of the alloy is, for example, 85% copper, 10% zinc and 5% silver.
The ionisation means may generally be installed in the swimming pool's filtration system. The ionisation means may preferably produce or introduce ions having an algaecidal (copper ions) or bactericidal (silver ions) into the liquid.
The control unit may preferably supply the necessary extra low voltage across the electrodes. The resultant current may produce positively charged ions of the constituent metals which are then carried into the pool and become part of the chemistry of the pool water. The input power to the controller may suitably be 110-250 volts at a frequency of approximately 50-60 hertz. It is preferred that the output power from the control unit is a 5 to 12 volt direct current at a maximum current of approximately 10 amperes which is transmitted to the rods. According to a particularly preferred embodiment, the power may be supplied to the ionisation rods at a level of about 90 milliamps and 5 volts of direct current.
According to a particularly preferred embodiment, the anode and cathode of the ionisation means as utilised in a domestic application such as a swimming pool may be approximately 25 mm in diameter and 100 mm in length. They are positioned approximately 15 mm apart. It is to be appreciated that in commercial applications which are generally larger in scale than domestic applications, larger rods may be preferred. A greater or lesser number of rods may be used in a commercial application.
The control unit may be connected to a power supply preferably through a timer. The control unit may suitably be associated with a circulation pump for circulating the water through the pool and/or the system in such a manner that the ionisation means is only operable when the circulation pump is activated.
As with a general electrolysis cell, the anode and the cathode may be sacrificial members. In order to prolong the lifespan of the rods, reduce debris build-up on the rods and minimise uneven wear to the rods, the polarity of the rods may be reversed periodically. The polarity may be reversed about each five to six minutes of operation for this purpose.
The silver and copper ions created by the ionisation means may preferably act to maintain the conductivity of the water without the addition of chemicals, particularly chlorine and also without the operation of a salt water chlorination device.
It is to be appreciated however that any ionisation means may be used according to the invention.
Any ultrasonic means may preferably be utilized according to the invention. The ultrasonic means may be configured to the particular type of liquid to be treated by adjusting any of the following parameters: flow rate through the ultrasonic means, volume of liquid to be treated, the level of cleanliness of the liquid initially or that required after treatment, water temperature or make-up for example pH.
More than one ultrasonic cleaning stage may preferably be required. The cleaning process may be enhanced through the use of agitation of the water in the pipes although it should be realized that the force provided by the pump moving the water through the system may agitate the water sufficiently.
According to a particularly preferred embodiment, the ultrasonic means may comprise a power supply connected to power source. The ultrasonic means may further comprise two aerials. The aerials may take the form of elongate members or wires. The aerials may preferably be wires approximately 2.5 mm in diameter.
The aerials are suitably wrapped about the pipe through which the water to be cleaned flows. The two aerials may be wound about the pipe starting from the same point on the pipe. Generally a minimum of seven revolutions may be required for the ultrasonic means to function optimally. It is preferred that each of the aerials revolve in opposed directions about the pipe, one in a clockwise direction and one in a counter-clockwise direction. The distance between each revolution may suitably be approximately 75 mm.
The power supply preferably creates a modulating ultrasonic field around the aerials, the field ranging in frequency from 50 to 80000 hertz. According to a particularly preferred embodiment, the power supply supplies a signal a variable frequency to each of the aerials. Preferably, the signal frequency starts at approximately 15 kilohertz and increases by 2 kilohertz over each two minute period. When a frequency of 71 kilohertz is reached, the frequency drops to 15 kilohertz and repeats the above process.
The ultrasonic means may be effective in converting salts and other solid material particularly calcium and silica based materials into an argonite material. Generally, salts and solids treated by ultrasonics may remain in the argonite form for up to 10 days.
A system according to the present invention operates in an in-line configuration; the actual wattage used may preferably be calculated on the basis of watts per liter per unit of time.
The electronic oxidation means may preferably take the form of a conventional electrolysis apparatus. The source of the voltage may be a low voltage, direct current electricity source. A higher voltage may not be needed as the conductivity in the water is heightened due to the addition of copper and silver ions created or introduced by the ionization means. Suitably an AC current is converted to a 25 ampere, 12 volt DC supply to the electrodes. Alternatively, a 15 ampere, 24 volts DC current may be used. The power supply may switch the polarity of the electrodes each twelve hour or twenty four hour period of operation in order to prolong the life of the electrodes.
In a particularly preferred embodiment, the application of a voltage across the electrodes in the electronic oxidation means may suitably increase the Oxidation Reduction Potential (ORP). The amount of change in the ORP may be dependent upon the voltage applied at the electrodes and the surface area of the electrodes.
In a particularly preferred embodiment, both of the electrodes in the electrolysis cell may be manufactured from titanium or be at least titanium coated. A preferred embodiment of the invention utilizes at least one coated steel electrode. The electrode may suitably be coated with an alloy of semi-precious metal, such as titanium or platinum.
The increase in ORP usually requires a level of Total Dissolved Solids in the water of between 500 to 800 ppm. The conductivity of the water treated according to the present invention is increased due to the operation of the ionization means and thus oxidation may be obtainable at lower levels of Total dissolved Solids due to the increased levels of ions in solution. Without the ionization means, the ORP may not be affected at lower levels of Total Dissolved Solids.
The system may preferably additionally comprise testing equipment to monitor the available parameters of the water and or swimming pool. The testing equipment may preferably continually sample the pool water.
Control means may also be provided for each element in the system, and/or the system as a whole. The cleaning elements may be operated at the same time or in any preset order of operation. The operation of the elements may overlap at least partially. It is preferred that the operation of the elements, including their start and finish time (if any), be controlled by the system control means. The control means may initiate a cleaning element's cleaning cycle, time the cycle, and shut down the element at the completion of the cleaning cycle.
The system according to the present invention may operate in at least a partially “in-line” formation whereby a portion of water is removed from the pool, treated by one or all of the cleaning processes, and then reintroduced into the pool. This type of system is common in the filtration of water in pools, spas and water features. According to an aspect of the present invention, the ionization means, the ultrasonic means and the electronic oxidation means may be located in the pipe work associated with a conventional in-line filtration system. It is also preferred that the elements of the present invention are located on the discharge side of any pump means provided to move the water through the system. The flow rate of water through the system may preferably be between 150 L/min and 300 L/min for domestic applications.
The system may operate continuously. One or more timers may also be provided.
According to a particularly preferred configuration, the apparatus of the present invention may be configured as two separate but interconnected physical components. The first component may suitably be the power supply/control means for the apparatus. The power supply/control means may also house the electronics associated with the apparatus within a pressure rated enclosure.
The enclosure may suitably be mounted adjacent but spaced from a standard 230-240 volt AC electrical power outlet and the swimming pool filter and pump.
The first component and in particular the power supply will generally be connectable to the electrical power outlet. The power supply may be associated with a 24 hour, 7 day timer in order to allow the operator of the apparatus to set the function and operation of the system and apparatus according to individual pool requirements.
The second component of the apparatus may be the ionization, oxidizing and ultrasonic chamber. This chamber will generally be plumbed into the pipe work of the pool filtration system between the pool filter and the return to the pool. The second component will be connected to the first component via at least electrical connections.
The second component may comprise an electronic oxidizing chamber and an ionization chamber in order after the pool filter with the ultrasonic aerials located between the respective chambers. Thus the water to be treated passes through the apparatus and system in the following order: electronic oxidizing chamber, pipe with ultrasonic aerials and the ionization chamber.
The above described treatment takes place in the swimming pool filtration system after the filter and before the water returns to the main body of the pool water.
The first components in the process are the Electronic Oxidizing plates. These have to be placed first in the system to get the cleanest water directly after the filter to prevent contamination of solids or CU/AG. Solids or CU/AG would build up on the plates rendering them ineffectual and dramatically shortening their operating life span.
The second components in the process are the copper and silver anode and cathode, these are placed second in the process as these are sacrificial and would plate out on the oxidizer plates if placed before them causing inefficiency and failure of the plates.
The third component in the system is the ultrasonics. These are third in the process to treat both the oxidized particles and the copper and silver ions directly after this process and before they return to the main body of the swimming pool water. The ultrasonics are preferably positioned last in the sequence to prevent particulates from the de-scaling process building up on the plates and copper silver electrodes.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying figures, in which like reference numerals refer to identical or functionally-similar elements throughout the separate views and which are incorporated in and form a part of the specification, further illustrate the embodiments and, together with the detailed description, serve to explain the embodiments disclosed herein.
FIG. 1 illustrates a schematic view of a continuous salt water chlorinator to illustrate the in-line nature of the system.
DETAILED DESCRIPTION
The particular values and configurations discussed in these non-limiting examples can be varied and are cited merely to illustrate at least one embodiment and are not intended to limit the scope thereof.
According to a preferred embodiment, a swimming pool cleaning and sterilization apparatus is provided. An in-line cleaning system is illustrated in FIG. 1 . A system such as the one illustrated in FIG. 1 may incorporate the ionization means and the electronic oxidation means according to the present invention. Alternatively, a system such as the one illustrated in FIG. 1 will have the electrolysis cell replaced with an ionization means, an ultrasonic cleaning means and an electronic oxidation means.
As can be seen from FIG. 1 , water from the pool enters the system and is moved around the system by a pump 11 . The pump moves the water from the intake pipe 12 into a filter 13 . The filter 13 is designed to remove material such as undissolved particulates, leaves or sticks, from the liquid stream.
The water may then proceed through a heater 14 or similar apparatus, if the pool is a heated type pool. The heating may also take place to attain the optimum treatment conditions for the water.
From the heater 14 , the water proceeds through an electrolytic cell 15 . The cell 15 as illustrated, is generally used according to the salt water chlorination process. As stated above, the electrolysis cell in FIG. 1 will be replaced with an ionization means, an ultrasonic cleaning means and an electronic oxidation means.
From the electrolysis cell 15 , the water proceeds back to the pool. The system is controlled by a control system 16 which generally houses the power pack as well. The system is fitted with a timer 17 to control the cycle time. The electrolysis cell 15 and the filter 13 are connected to the same power source.
The electronic oxidation means according to the invention operates to increase the oxidation reduction potential of the pool water.
Many chemical reactions take place when electrons are transferred from one material to another. In each case, one material is reduced by the addition of one or more electrons, while losing the same electrons oxidizes the other material. Therefore, the electrons that are available from the oxidized substance are added to the reduced material until an equilibrium condition is reached.
The size of an atom or ion and the number of electrons found in the outer electron shell determines the tendency of different materials to lose electrons. This is also known as the relative oxidation potentials of a particular material. The arbitrary standard for the potentials is the hydrogen electrode. The state of the reaction is then measured by the potential developed between an inert, noble metal electrode and a reference electrode.
The measuring electrode for ORP is usually gold or platinum. The noble metal donates and accepts electrons. The electrode acquires the electrochemical potential of the electrons, relative to the strongest redox equilibrium of the solution being measured. The electrode develops a voltage relative to the state of the reaction.
The reference electrode is the same electrode that is used for pH measurement. The ORP measurement becomes dependent on pH when the reaction involves hydrogen ions.
The system of the present invention operates with the ionization means and the electronic oxidation means in an in-line formation 21 and the ultrasonic aerials are positioned in an in-line configuration as well.
The ionization means comprises two rods of copper and silver alloy located in a clear plastic housing. The rods in domestic applications are approximately 25 mm in diameter and 100 mm in length and are positioned approximately 15 mm apart. The housing is plumbed into the pipe work of the in-line filtration system on the discharge side of the filter or pump prior to returning the water to the pool.
The average flow rate with the pumps available for this application is between 150 lts/min to 300 lts/min.
The ionization means power supply is connected to the domestic power supply preferably through a timer. The ionization means power supply has a piggy-back plug and the filtration systems circulating pump is plugged into the piggy back plug so the ionization means only runs with the pump in operation.
The power supply converts 240 volts AC to the required power supplies for each of the respective components of the apparatus. For the ionization chamber, the power is supplied at 200 milliamps and approximately 5 volts DC, and for the electronic oxidation chamber, the power is supplied at 15 amps and approximately 24 volts DC.
This low voltage DC power is connected to the copper and silver rods in the housing associated with the return pipe to the pool.
The polarity at the rods is reversed approximately every 6 minutes to allow even wear on the rods and prevent debris build up.
In the ultrasonic means, the power supply is connected to the domestic power source. Two aerials extend from the power supply. These aerials are wrapped around the pipe work of the system to be treated. A minimum of seven revolutions is required. One aerial revolves clockwise from the center and the other, anti-clockwise, the distance between the revolutions being approximately 75 mm.
The power supply, when operating, creates a modulating ultrasonic field around the aerials, which ranges between 50 Hz to 50,000 Hz. The power supply supplies a signal a variable frequency to each of the aerials. The signal frequency starts at approximately 15 kilohertz and increases by 2 kilohertz over each two minute period. When a frequency of 71 kilohertz is reached, the frequency drops to 15 kilohertz and repeats the above process.
Salts and solids are difficult to remove from water. These salts and solids easily precipitate out as scale on all surfaces within the circulating pipe work and devices within the system. These salts and solids are perfect for mollusks and parasites to use as building blocks for proliferation.
The ultrasonic means does not remove these salts and solids, but rather affects them at molecular levels. Calcium or silica molecules are very easily adhered to each other and precipitate out as scale on surfaces within the wet side of pool systems. The higher the level of this particulate the more scale which will occur.
Mollusks and parasites use these salts as building material for their growth and consequently they are present in a system having high levels of these salts and solids.
Ultrasonics adapts these salts and solids from the snowflake-like molecule, to a long thin brittle argonite molecule. This molecule has great difficulty adhering to surfaces or other materials and consequently scale build-up is reduced and existing scale is broken down and removed. Mollusks protective shells are also weakened and the sanitizer (created by the ionization means) is more easily able to penetrate the weakened shell and the mollusk or parasite is killed. New parasites or mollusks have difficulty surviving in the system as their protective barrier obtained from the calcium or silica is now unable to bond and therefore they cannot proliferate.
In use, the electronic oxidation means uses multiple amounts of steel plates coated with an alloy of semi-precious metals placed in a poly vinyl chloride (PVC) cell plumbed into the filtration circuit of the system. The electronic oxidation means operates on the principle of electrolysis with a cathode and an anode plate system. An AC/DC power supply allows production of approximately 15 ampere output at 24 volts of DC current. This power supply switches polarity approximately every 24 hours of operation.
When the system is operated the Oxygen Reduction Potential (ORP) of the water is increased. The amount of ORP generated is dependent on the voltage applied at the titanium plates and the surface area of the plates.
Conductivity in the water is increased and the oxidization is obtainable at lower Total Dissolved Solids due to the levels of copper and silver ions in the water.
The apparatus of the present invention is configured as two separate but interconnected physical components. The first component comprises the power supply/control means for the apparatus. The power supply/control means also houses the electronics associated with the apparatus within a pressure rated enclosure.
The enclosure is mounted adjacent to, but spaced from a standard 230-240 volt AC electrical power outlet and the swimming pool filter and pump.
The power supply will be connectable to the electrical power outlet. The power supply is associated with a 24 hour, 7 day timer in order to allow the operator of the apparatus to set the function and operation of the system and apparatus according to individual pool requirements.
The second component of the apparatus comprises the ionization, oxidizing and ultrasonic chamber. This chamber is plumbed into the pipe work of the pool filtration system between the pool filter and the return to the pool. The second component is connected to the first component via at least electrical connections.
The second component comprises an electronic oxidizing chamber and an ionization chamber in order after the pool filter with the ultrasonic aerials located between the respective chambers. Thus the water to be treated passes through the apparatus and system in the following order: electronic oxidizing chamber, pipe with ultrasonic aerials and the ionization chamber.
According to a particularly preferred embodiment, the system parameters and layout is as follows:
The system can be provided in two physical components. The first component is the power supply, which houses the electronics. These components are housed in an [i.p 35 rated] enclosure, which mounts within one [1] meter of the electrical power outlet and the swimming pool filter and pump.
The second component is the ionization, oxidizing and ultrasonic chamber, which is plumbed into the filtration systems pipe work on the section between the filter and the return to the pool water. This unit is connected electrically to the first component, the power supply.
The power supply can be plugged into a general power outlet of 230-240 volts AC. The power supply has a 24 hour 7 day timer where by the operator can set the system automatically to start and stop depending on individual pool requirements.
Electronic Oxidization Process.
The power supply, supplies power to the oxidizing plates at 15 Amps @ 24 Volts D.C. The polarity of the power supply reverses every twenty four [24] hour run time.
Ionization Process.
The power supply, supplies power for the ionization process at 90 milliamps @ 5 Volts D.C. The polarity of the power supply reverses every six [6] minutes.
Ultrasonic Process.
The power supply, supplies a signal to the two [2] ultrasonic aerials. Starting at fifteen kilohertz and increasing by two [2] kilo hertz increments over a two [2] minute period. When it reaches seventy-one [71] kilohertz and then reverts back to fifteen [15] kilohertz and repeats over again. The second component of the system the treatment chambers.
The First Chamber.
This chamber houses the electronic oxidizing plates which are capable of drawing fifteen amps [15] @ 24 Volts D.C. The plates are Titanium coated with Iridium. Unless these plates are made of such material there will be no reaction when the pool water is circulated past the plate at the correct water balance. (Correct water balance, Ph 7.2-7.4, Alkalinity 80-150 ppm, Calcium hardness 200+ppm, TDS's pool water 800-1000 ppm)
The Second Chamber.
This chamber houses the ionization rods these are an alloy of Copper Eighty Five [85]% Silver Five [5]% and Zinc Ten [10]%. These rods are placed after the Electronic oxidizer cell to prevent plating of the copper and sliver ions on the oxidizer plates. If the ionization rods were placed before the oxidizer, this would over a short time cause the oxidizer plates to fail.
After the Two Chambers.
The two-[2] ultrasonic aerials are wound onto the pipe. The wire is 2.5-millimeter wound on from the starting point, minimum rounds seven [7] and at opposing directions from the center. Clockwise and anti-clockwise from the center.
A particular embodiment of the present invention is described in the Experimental Report of ANNEX: “ Pseudomonas aeruginosa Disinfection in Pool Spas; Laboratory experiments conducted with Envrioswim System for WaterTech Services International Pty Ltd.” by Paul Wright, Ph.D, which is incorporated herein by reference in its entirety.
In the present specification and claims, the word “comprising” and its derivatives including “comprises” and “comprise” include each of the stated integers but does not exclude the inclusion of one or more further integers.
It will be appreciated that variations of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims.
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An in-line cleaning and sanitation apparatus for cleaning a liquid, the apparatus including electronic oxidation means to increase the oxidation reduction potential of the liquid, and ionization means to produce ions having an algaecidal or bactericidal effect into the liquid, in that order together with ultrasonic cleaning means to introduce sound waves into the liquid, and wherein the ionization means, the ultrasonic cleaning means and the electronic oxidation means are operated simultaneously for a period to clean and sanitize the liquid in the absence of added salt, chlorine or other chemicals.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of application Ser. No. 14/494,787, filed Sep. 24, 2014, currently pending;
[0002] Which was a divisional of application Ser. No. 13/855,970, filed Apr. 3, 2013, now U.S. Pat. No. 8,880,966, granted Nov. 4, 2014;
[0003] Which was a divisional of application Ser. No. 13/551,167, filed Jul. 17, 2012, now U.S. Pat. No. 8,433,962, granted Apr. 30, 2013;
[0004] Which was a divisional of application Ser. No. 13/197,000, filed Aug. 3, 2011, now U.S. Pat. No. 8,250,421, granted Aug. 21, 2012;
[0005] Which was a divisional of application Ser. No. 13/012,117, filed Jan. 24, 2011, now U.S. Pat. No. 8,020,059, granted Sep. 13, 2011;
[0006] Which was a divisional of application Ser. No. 12/887,672, filed Sep. 22, 2010, now U.S. Pat. No. 7,900,110, granted Mar. 1, 2011;
[0007] Which was a divisional of application Ser. No. 12/640,941, filed Dec. 17, 2009, now U.S. Pat. No. 7,823,037, granted Oct. 6, 2010;
[0008] Which was a divisional of application Ser. No. 12/182,605, filed Jul. 30, 2008, now U.S. Pat. No. 7,669,099, granted Feb. 23, 2010;
[0009] Which was a divisional of application Ser. No. 11/370,017, filed Mar. 7, 2006, now U.S. Pat. No. 7,421,633, granted Sep. 2, 2008;
[0010] And this application claims priority from Provisional Application No. 60/663,953, filed Mar. 21, 2005, and is related to the following patent applications or patents:
[0011] Application Ser. No. 11/292,643, “Reduced Signal Interface Method and Apparatus,” now U.S. Pat. No. 7,308,629, issued Dec. 11, 2007;
[0012] Application Ser. No. 11/293,061, “Selectable Pin Count JTAG,” now U.S. Pat. No. 7,328,387, issued Feb. 5, 2008;
[0013] Application Ser. No. 11/258,315, “2 Pin Bus”, now U.S. Pat. No. 8,412,853, issued Apr. 2, 2013;
[0014] Application Ser. No. 08/918,872, U.S. Pat. No. 6,073,254 “Selectively Accessing IEEE 1149.1 Taps in a Multiple Tap Environment,” issued Jun. 6, 2000; and
[0015] Application Ser. No. 11/292,597, “Multiple Test Access Port Protocols Sharing Common Signals”, now U.S. Pat. No. 7,571,366, issued Aug. 4, 2009.
BACKGROUND OF THE DISCLOSURE
[0016] This disclosure relates in general to IC signal interfaces and in particular to IC signal interfaces related to test, emulation, debug, and trace operations.
DESCRIPTION OF THE RELATED ART
[0017] FIG. 1 illustrates a conventional 5 wire JTAG interface 106 between an external JTAG controller 100 and Tap Domains 104 within a target IC 102 . Modern day ICs typically have a Tap Domain associated with the IC's JTAG boundary scan test operations and/or one or more Tap Domains associated with each one or more core circuits designed into the IC. The interface couples the TDO output of JTAG controller to the IC's TDI pin input, the TMS output of the JTAG controller to the IC's TMS pin input, the TCK output of the JTAG controller to the IC's TCK pin input, the TDI input of the JTAG controller to the IC's TDO pin output, and the TRST output of the JTAG controller to the IC's TRST pin input. The IC's TDI, TDO, TMS, TCK, and TRST pins 108 are dedicated for interfacing to the JTAG controller and cannot be used functionally.
[0018] In response to the TMS and TCK signals, the Tap Domains 104 of IC 102 communicates data to and from the JTAG controller via the TDO to TDI connections. A low output on the JTAG controller's TRST output causes the Tap Domains of IC 102 to enter a reset state. The JTAG controller receives a clock input (CKIN) from a clock source 110 . The CKIN input times the operation of the JTAG controller, which in turn times the operation of the Tap Domains in IC 102 . The JTAG controller can be used to perform test, emulation, debug, and trace operations in the target IC by accessing the embedded Tap Domains via the 5 wire interface. The arrangement between the JTAG controller and the target IC and its use in performing test, emulation, debug, and trace operations is well known in the industry.
[0019] FIG. 2 illustrates an alternate arrangement whereby a JTAG controller 200 is interfaced to a target IC 202 via the JTAG bus 108 and a Debug/Trace bus 204 . The JTAG controller 200 differs from the JTAG controller of FIG. 1 in that it includes additional circuitry and input/outputs for interfacing to the IC's Debug/Trace circuitry 204 . As in FIG. 1 , the JTAG bus 108 is coupled to Tap Domains 104 within the IC via IC pins 108 . The Debug/Trace bus 204 is coupled to Debug/Trace circuitry 206 within the IC via N IC pins 208 . The JTAG bus is used to input commands and data that enable the Debug/Trace circuitry to perform debug and/or trace operations. The Debug/Trace bus signals can be used for a myriad of operations including but not limited to; (1) importing and/or exporting data between the JTAG controller 200 and Debug/Trace circuitry 206 during debug and/or trace operations, (2) operating as a communications bus between the JTAG controller 200 and Debug/Trace circuitry 206 , and ( 3 ) inputting and/or outputting trigger signals between the JTAG controller 200 and Debug/Trace circuitry 206 during debug and trace operations.
[0020] One of the key advantages of the debug/trace bus 204 is that it increases the data input/output bandwidth between the JTAG controller and target IC during debug/trace operation over what is possible using only the 5 wire JTAG bus 106 . For example, the data input/output bandwidth of the JTAG bus is limited to the amount of data that can flow between the JTAG controller and IC over the single TDO to TDI signal wire connections. Since the debug/trace bus can have N signal wire connections between the JTAG controller and IC (N), its data bandwidth can be much greater than the JTAG bus bandwidth. Increased data bandwidth between the JTAG controller and IC facilitates debug/trace operations such as; (1) monitoring real time code execution, (2) accessing embedded memories, (3) uploading/downloading code during program debug, and (4) triggered output trace functions.
[0021] With the current trend towards smaller IC packaging to allow more ICs to be placed on smaller assemblies used in mobile applications, such as cell phones and personal digital assistants, the number of IC pins is being reduced. It is therefore a benefit of the present disclosure to provide a reduced pin count interface on ICs for test, emulation, debug, and trace operations, as this will allow more IC pins to be available for functional purposes. While it is advantageous to reduce the pin counts of both the JTAG and Debug/Trace buses of FIGS. 1 and 2 , this application focuses on reducing the JTAG bus pins of an IC.
[0022] In addition to reducing the JTAG bus pins of an IC, a second benefit of the present disclosure is to maintain a high communication bandwidth over the reduced JTAG pins. As will be shown, the present disclosure provides a data communication bandwidth using the reduced JTAG pins that is equal to one half the data communication bandwidth using a full set of JTAG pins. For example, if the JTAG controller 100 can communicate data to and from Tap Domains 104 of FIG. 1 at 100 Mhz using the full JTAG bus 106 , a JTAG controller adapted according to the present disclosure can communicate data to and from Tap Domains 104 of an IC, also adapted according to the present disclosure at 50 Mhz.
[0023] One prior art technique, referenced herein, is called the J-Link System. The J-Link system provides a way to reduce the JTAG pins of an IC from the standard five pins to a reduced set of one or two pins. In a chart shown in the J-Link reference, it is seen that the J-Link interface provides a data communication bandwidth that is one sixth that of the conventional JTAG 5 pin interface. For example and as stated in the J-Link reference, if the standard 5 pin JTAG interface can operate at 48 Mhz, the J-Link interface operates at one sixth of the 48 Mhz frequency, or at 8 Mhz. In comparison and as will be shown herein, if the standard 5 pin JTAG interface can operate at 48 Mhz, the reduce pin approach of the present disclosure can operate at one half the 48 Mhz frequency, of at 24 Mhz. Thus the present disclosure provides a three times improvement in operating frequency over the referenced J-Link approach. The present disclosure is therefore capable of performing operations related to IC test, debug, emulation, and trace at three times the bandwidth of the referenced J-Link approach.
SUMMARY OF THE DISCLOSURE
[0024] The present disclosure provides a reduced pin interface for JTAG based test, emulation, debug, and trace transactions between a JTAG controller and a target IC.
DESCRIPTION OF THE VIEWS OF THE DRAWINGS
[0025] FIG. 1 illustrates a conventional 5 signal interface between a JTAG controller and target IC.
[0026] FIG. 2 illustrates a conventional JTAG controller interfaced to a target IC via a 5 signal JTAG bus and an N signal Debug/Trace bus.
[0027] FIG. 3 illustrates a JTAG controller interfaced to a target IC via a 2 signal JTAG bus according to the present disclosure.
[0028] FIGS. 4A-4C illustrate various conventional Tap Domain arrangements within a target IC.
[0029] FIG. 5A illustrates a circuit example of the parallel to serial controller (PSC) circuit of the present disclosure.
[0030] FIG. 5B illustrates a timing diagram of the operation of the PSC circuit of FIG. 5A .
[0031] FIG. 6A illustrates a circuit example of the controller within the PSC circuit of FIG. 5A .
[0032] FIG. 6B illustrates a timing diagram of the operation of the controller of FIG. 6A .
[0033] FIG. 7A illustrates a circuit example of the serial to parallel controller (SPC) circuit of the present disclosure.
[0034] FIG. 7B illustrates a timing diagram of the operation of the SPC circuit of FIG. 7A .
[0035] FIG. 8A illustrates a circuit example of the controller within the SPC circuit of FIG. 7A .
[0036] FIG. 8B illustrates a timing diagram of the operation of the controller of FIG. 8A .
[0037] FIG. 9A illustrates a circuit example of the master reset and synchronizer (MRS) circuit within the SPC circuit of FIG. 7A .
[0038] FIG. 9B illustrates a state diagram of the operation of the MRS circuit of FIG. 9A .
[0039] FIG. 9C illustrates a timing diagram of the operation of the MRS circuit of FIG. 9A .
[0040] FIG. 10 illustrates the state diagram of the IEEE standard 1149.1 Tap controller state machine.
[0041] FIG. 11A illustrates a circuit example of the input/output (I/O) circuits within the PSC and SPC circuits.
[0042] FIG. 11B illustrates the signaling cases for the I/O circuits of FIG. 11A .
[0043] FIG. 12 illustrates each signaling case of FIG. 11B in more detail.
[0044] FIG. 13A illustrates an example circuit for determining the appropriate TDI or IN signal output of the I/O circuits of FIG. 11 .
[0045] FIG. 13B illustrates the truth table used for determining the appropriate TDI or IN signal output based on the voltage level of the data I/O (DIO) signal.
[0046] FIG. 14A illustrates the 2 signal connection between the PSC of the JTAG controller and the SPC of the target IC according to the present disclosure.
[0047] FIG. 14B illustrates a timing diagram of the operation of the PSC and SPC circuits of FIG. 14A performing JTAG transactions between the JTAG controller and the Tap Domains of the target IC.
[0048] FIG. 14C illustrates a timing diagram of the operation of the PSC and SPC circuits of FIG. 14A performing a single bit data register scan between the JTAG controller and the Tap Domains of the target IC.
[0049] FIG. 15 illustrates a Texas Instruments SN74ACT8990 JTAG bus controller chip operating to compensate for cable delays.
[0050] FIG. 16 illustrates a 2 pin realization of the present disclosure whereby the CLK signal is driven by a clock source within the JTAG controller.
[0051] FIG. 17 illustrates a 2 pin realization of the present disclosure whereby the CLK signal is driven by an internal clock source of the target IC.
[0052] FIG. 18 illustrates a 1 pin realization of the present disclosure whereby the CLK signal is driven by an external clock source that functionally inputs to the target IC.
[0053] FIG. 19 illustrates a 1 pin realization of the present disclosure whereby the CLK signal is driven by an internal clock source of the target IC that functionally outputs from the IC.
[0054] FIG. 20 illustrates a 2 pin realization of the present disclosure whereby the CLK signal is driven by an clock source external of the JTAG controller and target IC.
[0055] FIG. 21A illustrates an alternate circuit example of the parallel to serial controller (PSC) circuit of the present disclosure.
[0056] FIG. 21B illustrates a timing diagram of the operation of the alternate PSC circuit of FIG. 5A .
[0057] FIG. 22A illustrates an alternate circuit example of the serial to parallel controller (SPC) circuit of the present disclosure.
[0058] FIG. 22B illustrates a timing diagram of the operation of the SPC circuit of FIG. 7A .
[0059] FIG. 23A illustrates the 3 signal connection between the FIG. 21A alternate PSC of the JTAG controller and the FIG. 22A alternate SPC of the target IC of according to the present disclosure.
[0060] FIG. 23B illustrates a timing diagram of the operation of the alternate FIG. 21A PSC and FIG. 22A SPC circuits performing JTAG transactions between the JTAG controller and the Tap Domains of the target IC.
[0061] FIG. 24 illustrates a 3 pin realization of the alternate version of the present disclosure whereby the CLK signal is driven by a clock source within the JTAG controller.
[0062] FIG. 25 illustrates a 3 pin realization of the alternate version of the present disclosure whereby the CLK signal is driven by an internal clock source of the target IC.
[0063] FIG. 26 illustrates a 2 pin realization of the alternate version of the present disclosure whereby the CLK signal is driven by an external clock source that functionally inputs to the target IC.
[0064] FIG. 27 illustrates a 2 pin realization of the alternate version of the present disclosure whereby the CLK signal is driven by an internal clock source of the target IC that functionally outputs from the IC.
[0065] FIG. 28 illustrates a 3 pin realization of the alternate version of the present disclosure whereby the CLK signal is driven by an clock source external of the JTAG controller and target IC.
DETAILED DESCRIPTION
[0066] FIG. 3 illustrates the approach of the present disclosure to reduce the number of JTAG pins on an IC 300 and the number of JTAG bus signal connections between the IC 300 and JTAG controller 100 . IC 300 and others illustrated in this disclosure could represent any type of integrated circuit including but not limited to, a microcontroller IC, a microprocessor IC, a digital signal processor IC, a mixed signal IC, an FPGA/CPLD IC, an ASIC, a system on chip IC, a peripheral IC, a ROM memory IC, or a RAM memory IC. In FIG. 3 , the JTAG controller 100 is interfaced to a Parallel to Serial Controller (PSC) circuit 302 via TDO, TMS, CKIN, TDI, and TRST signals. The PSC 302 may be a separate circuit from the JTAG controller 100 or the PSC 302 and JTAG controller 100 may be integrated to form a new JTAG controller 304 . The PSC 302 is interfaced to a Serial to Parallel Controller (SPC) circuit 306 in IC 300 via a bus comprising a data I/O (DIO) signal 308 and a clock (CLK) signal 310 . The SPC 306 is interfaced to Tap Domains 104 in the IC 300 via TDI, TMS, TCK, TDO, and TRST signals. As will be described later in regard to FIGS. 16-20 , the CLK signal 310 may be driven by a clock source associated with the JTAG controller 100 , a clock source associated with the IC 300 , or a clock source not associated with the JTAG controller 100 or IC 300 .
[0067] FIG. 4A illustrates that the Tap Domain block 104 of IC 300 may consist of a single 1149.1 Tap architecture.
[0068] FIG. 4B illustrates that the Tap Domain block 104 of IC 300 may consist of a series of daisy-chained Tap architectures 1−N.
[0069] FIG. 4C illustrates that the Tap Domain block 104 of IC 300 may consist of a group of Tap architectures 1−N that may be selected individually or linked serially together in various daisy-chain arrangements using linking circuitry 400 . An example of such linking circuitry 400 has been described in referenced U.S. Pat. No. 6,073,254.
[0070] FIG. 5A illustrates the PSC circuit 302 in more detail. The PSC consists of a controller 500 , a parallel input serial output (PISO) register 502 , and an input/output (I/O) circuit 504 . PISO 502 inputs parallel TMS and TDO signals from the JTAG controller 100 , the TRST signal from the JTAG controller 100 , a load (LD) signal from controller 500 , and outputs a serial output (OUT) signal to I/O circuit 504 .
[0071] A simplified view of PISO 502 shows it containing two serially connected FFs 503 and 505 . While the TRST signal from the JTAG controller is low, FFS 503 and 505 are asynchronously set to logic ones and do not respond to the CLK or LD inputs. This can be achieved, for example, by connecting the TRST signal to the Set input of FFs 503 and 505 . The OUT signal is therefore high while TRST is low. When TRST goes high FFS 503 and 505 are enabled to respond to the CLK and LD inputs. In response to the LD input, FFs 503 and 505 asynchronously load TMS and TDO output from the JTAG controller, respectively. Once loaded, the FFs are shifted by CLK 310 to output TMS then TDO signals to I/O circuit 504 via the OUT signal.
[0072] Controller 500 inputs the CLK signal 310 , the TRST signal from the JTAG controller 100 . Controller 500 outputs the asynchronous LD signal to the PISO and a clock signal to the CKIN input of JTAG controller 100 . While TRST is low, the controller is reset and does not respond to the CLK input. While reset the LD and CKIN outputs from the controller are low. When TRST goes high, the controller is enabled to respond to the CLK input and output LD and CKIN output signals.
[0073] I/O circuit 504 inputs the OUT signals from the PISO and outputs them on DIO 308 . The I/O circuit 504 also inputs signals from DIO 308 and outputs them to the TDI input of JTAG controller 100 . I/O circuit 504 is designed to allow the output of OUT signals to DIO 308 and the input of TDI signals from DIO 308 to occur simultaneously. The simultaneous input and output operation of I/O circuit 504 will be described in detail later in regard to FIGS. 11A , 11 B, 12 , 13 A, and 13 B.
[0074] The operation of PSC 302 (while TRST is high) is illustrated in the timing diagram of FIG. 5B . In response to the CLK input 310 , the controller 500 operates to periodically output the LD signal to PISO 502 and the CKIN signal to JTAG controller 100 . Also the CLK input 310 times the PISO 502 to shift data from its OUT output to the I/O circuit 504 . The I/O circuit passes the OUT signal to the DIO 308 signal. The CKIN signal times the operation of the JTAG controller 100 . The LD signal causes the PISO to asynchronously load the TMS and TDO signal pattern from JTAG controller 100 . Once loaded, the TMS and TDO pattern is shifted out of the PISO to the I/O circuit in response to the CLK signal.
[0075] The following describes the PSC's repeating load and shift out sequence. A TMS and TDO pattern 510 is asynchronously loaded into the PISO in response to LD signal 512 . CLK signal 514 shifts out the TMS signal portion of pattern 510 on the OUT output of the PISO, then CLK signal 516 shifts out the TDO signal portion of pattern 510 on the OUT output of the PISO. CKIN signal 518 advances the JTAG controller to output the next TMS and TDO pattern 520 . LD signal 522 asynchronously loads the next TMS and TDO pattern 520 into the PISO. CLK signal 524 shifts out the TMS signal portion of pattern 520 on the OUT output of the PISO, then CLK signal 526 shifts out the TDO signal portion of pattern 520 on the OUT output of the PISO. CKIN signal 528 advances the JTAG controller to output the next TMS and TDO pattern 530 which is asynchronously loaded into the PISO by LD signal 532 and shifted out by CLK signals 534 and 536 . The JTAG controller is advanced to output the next TMS and TDO pattern 540 during CKIN 538 . The above described pattern load, pattern shift, and JTAG controller advancement process repeats as long as the CLK input 310 is active.
[0076] When the JTAG controller 100 receives a CKIN input it will output a new TMS and TDO signal pattern to PISO 502 and input the TDI signal from I/O circuit 504 . The TMS signal output will control the Tap state machine of the target IC's Tap Domain 104 according to FIG. 10 , the TDO signal will provide the TDI input signal to the target IC's Tap Domain (if in the Shift-DR/IR state), and the TDI input signal will input data to the JTAG controller from the target IC's Tap Domain (if in the Shift-DR/IR state).
[0077] FIG. 6A illustrates an example implementation of controller 500 . Controller 500 consists of FF 600 , FF 602 , AND gates 604 - 608 , and delay inverter 610 . While the TRST input from the JTAG controller 100 is low, FFs 600 and 602 are reset and the LD and CKIN outputs are low. When TRST goes high, FFs 600 and 602 are enabled to respond to the CLK input 310 . FF 600 toggles its load enable (LDENA) output during each rising edge of CLK input 310 . FF 602 stores the LDENA output of FF 600 at its clock enable (CKENA) output on each falling edge of CLK input 310 . AND gate 604 outputs a high when LDENA is high and CLK is low. AND Gate 606 and delay inverter 620 operate together to produce a high going pulse on the LD output whenever the output of AND gate 604 goes high.
[0078] The duration of the high going pulse on the LD signal is determined by the input to output signal delay through delay inverter 610 . The duration of the LD pulse should be long enough to asynchronously load the PISO with the TMS and TDO pattern but not long enough to interfere with the shifting operation of the PISO. For example, the high going LD pulse should return low for a sufficient amount of time prior to the next rising edge of the shifting CLK input so as to not interfere with the shift operation. The CKENA output of FF 602 enables AND gate 608 to pass the CLK signal 310 to the CKIN output. CKENA changes state on the falling edge of CLK 310 to allow a AND gate 608 to be enabled prior to the rising edge of CLK 310 to allow for good clock gating operation at the CKIN output.
[0079] The operation of controller 500 is illustrated in the timing diagram of FIG. 6B . In response to the CLK input 310 , the controller 500 operates to periodically output the LD and CKIN signals. As mentioned, the CKIN signal times the operation of the JTAG controller 100 and the LD signal causes the PISO to asynchronously load the TMS and TDO pattern from the JTAG controller 100 . On each rising edge of CLK 310 the LDENA output of FF 600 toggles its state. On each falling edge of CLK 310 the CKENA output of FF 602 is set to the state of the LDENA input to FF 602 . A LD pulse output occurs each time LDENA is high and the CLK goes low. A CKIN output occurs each time CKENA is high and the CLK is high.
[0080] FIG. 7A illustrates the SPC circuit 306 in more detail. The PSC consists of a controller 700 , a serial input parallel output (SIPO) register 702 , update register 704 , Tap state machine (TSM) 706 , master reset and synchronizer (MRS) circuit 708 , input/output (I/O) circuit 710 , and power on reset circuit (POR) 712 .
[0081] POR circuit 712 produces a temporary low active power on reset pulse whenever the target IC is first power up. This power on reset pulse is used to initialize the MRS circuit. When initialized, the MRS circuit 708 outputs a low on the master reset (MRST) signal to initialize other circuitry within the SPC 306 and to set TRST input of the connected Tap Domains 104 low. When TRST is low, the Tap Domains 104 are forced to the Test Logic Reset state. The Test Logic Reset state is a state of the 1149.1 Tap state machine and is shown in the Tap state machine diagram of FIG. 10 . The POR circuit 712 may exist in the SPC 306 as shown or it may exist external to the SPC, i.e. as a separate circuit within the target IC. The function of the POR circuit to initialize the MRS circuit 708 may be achieved by other means. For example a reset pin of the IC may be substituted for the POR circuit 712 and used to initialize the MRS circuit 708 .
[0082] Controller 700 inputs the CLK signal 310 , a controller enable (CENA) signal from MRS 708 , a reset (RST) signal from TSM 706 . The controller outputs an update clock (UCK) to update register 704 and a TCK signal to Tap Domains 104 and TSM 706 . A detail description of controller 700 will be given in FIGS. 8A and 8B .
[0083] I/O circuit 710 inputs an output enable (OE) signal from TSM 706 . The OE signal is used to enabled or disable the output drive of I/O circuit 710 . I/O circuit 710 inputs signals from DIO 308 and outputs them to SIPO 702 via the IN signal. If the OE is set to enable the output drive of I/O circuit 710 , TDO signals input from Tap Domains 104 are output on DIO. If the OE is set to disable the output drive of I/O circuit 710 , TDO signals are not output on DIO and the I/O circuit operates to only input DIO signals to SIPO 702 via the IN signal. I/O circuit 504 is designed to allow the output of TDO signals to DIO 308 , if enabled by OE, and the input of IN signals from DIO 308 to occur simultaneously. The simultaneous input and output operation of I/O circuit 710 will be described in detail later in regard to FIGS. 11A , 11 B, 12 , 13 A, and 13 B.
[0084] SIPO 702 inputs the serialized TMS and TDO signal patterns from the IN output of I/O circuit 710 in response to the CLK input 310 and outputs them to update register 704 . The update register 704 inputs the TDO and TMS outputs from the SIPO and outputs them as TDI and TMS signals to Tap Domains 104 . The update register also inputs the MRST signal from the MRS circuit 708 . While the MRST signal is active low the TDO and TMS outputs of the update register 704 are set high. While the MRST signal is inactive high the update register can respond to the update clock (UCK) signal from controller 700 to load TDO and TMS signals from the SIPO 702 .
[0085] A more detail view of SIPO 702 and update register 704 shows the SIPO containing two serially connected FFs 703 and 705 . In response to the CLK signal 310 , FFs 703 and 705 shift in the serialized TMS and TDO signals from the IN output of I/O circuit 710 . Once the TMS and TDO signals are shifted in they are transferred in parallel to FFs 707 and 709 in the update register 704 in response to the UCK signal where they are input to the TDI and TMS inputs of Tap Domains 104 . The update register serves to provide the current TDI and TMS input pattern to the Tap Domains 104 while the SIPO operates to serially input the next TDO and TMS pattern to be input to the Tap Domains 104 . As mentioned, the outputs of FFs 707 and 709 are asynchronously forced high in response to a low on the MRS signal, which results in highs being input to the TDI and TMS inputs of Tap Domain 104 . This can be achieved, for example, by connecting the MRS signal to the Set input of FFs 707 and 709 .
[0086] TSM circuit 706 inputs the TMS output from the update register, the TCK output of controller 700 , and the MRST output from MRS circuit 708 . TSM circuit 706 outputs a reset (RST) signal to controller 700 and MRS circuit 708 , and the OE signal to I/O circuit 710 . The TSM is simply the Tap state machine defined in IEEE standard 1149.1. The MRST input from MRS circuit 708 is connected to the standard “TRST” input of 1149.1 TSM, the TCK input from controller 700 is connected to the standard “TCK” input of the 1149.1 TSM, the TMS input from controller 700 is connected to the standard “TMS” input of the 1149.1 TSM, the RST output from TSM is connected to the standard “Reset*” output of the 1149.1 TSM, and the OE output of the TSM is connected to the standard “Enable” output of the 1149.1 TSM.
[0087] The TSM circuit is used by the present disclosure to allow the SPC to track the Tap states of the connected Tap Domains, especially the states that control the OE and RST outputs. The operation of the 1149.1 Tap state machine is defined in the 16 states shown in FIG. 10 . While it is possible to actually use signals from the Tap state machine(s) of the connected Tap Domains 104 for tracking, instead of implementing a dedicated TSM circuit 706 in the SPC 306 , the required signals (OE and RST) may not always be available from the Tap Domains 104 . For example, connected Tap Domains 104 of hard cores (i.e. cores that are fixed and cannot be modified) may not provide OE and RST output signal terminals for connection to the SPC's OE and RST terminals. Further, Tap Domains 104 having linking arrangements as shown in FIG. 4C may present OE and RST signal switching complexities between the SPC 306 and linked Taps within Tap Domains 104 . Therefore, the SPC 306 preferably includes a TSM circuit 706 to insure simplicity in tracking the states of connected Tap Domains 104 .
[0088] MRS circuit 708 inputs the IN output of I/O circuit 710 , the CLK signal 310 , the RST signal from TSM 706 , and the power on reset output of POR circuit 712 . MRS circuit 708 outputs the MRST signal to Tap Domains 104 , TSM 706 , and update register 704 and the CENA signal to controller 700 . The purposes of the MRS circuit 708 are; (1) to maintain the SPC and connected Tap Domains 104 in a reset state when the target IC is operating normally in a system with no JTAG controller 100 and PSC 302 connected to the SPC's DIO 308 and CLK 310 signals, and (2) to allow synchronizing the operation of the SPC 306 to the operation of a JTAG controller 100 and PSC 302 when the JTAG controller and PSC are connected to the SPC's DIO and CLK signals. Synchronizing the operation of the SPC to the operation of the JTAG controller and PSC is important since it allows the serialized TMS and TDO patterns output from PSC to be correctly input as serialized TMS and TDO patterns to the SPC. A detail description of MRS circuit 708 will be given in regard to FIGS. 9A-9C .
[0089] The operation of SPC 306 is illustrated in the timing diagram of FIG. 7B . In response to the CLK input 310 , the controller 700 operates to periodically output the UCK signal to the update register 704 and the TCK signal to Tap Domains 104 and TSM 706 . Also the CLK input 310 times the SIPO 702 to shift in data from the IN output of the I/O circuit 710 . The I/O circuit passes DIO input signals to the IN output. The TCK signal times the operation of the Tap Domains 104 . The UCK signal causes the update register 704 to load the parallel TDO and TMS signal pattern output of the SIPO 702 . Once loaded, the TDO and TMS signal pattern is applied to the TDI and TMS inputs of Tap Domains 104 . The Tap Domains 104 respond to the TDI and TMS signal pattern in response to the TCK.
[0090] The following describes the SPC's repeating shift in and update sequence. A serial TMS and TDO bit stream 718 is shifted into SIPO 702 in response to CLK signals 720 and 722 . The shifted in TMS and TDO signals form a parallel TDO and TMS output pattern 724 from SIPO 702 that is clocked into to the update register 704 in response to UCK signal 726 . The TDO and TMS pattern 724 in the update register 704 is applied to the TDI and TMS inputs of Tap Domains 104 . TCK signal 728 clocks the Tap Domains 104 to respond to the TDI and TMS pattern 724 from update register 704 . The next serial TMS and TDO bit stream 730 is shifted into SIPO 702 in response to CLK signals 732 and 734 . The shifted in TMS and TDO signals form a parallel TDO and TMS output pattern 736 from SIPO 702 that is clocked into to the update register 704 in response to UCK signal 738 . The TDO and TMS pattern 738 in the update register 704 is applied to the TDI and TMS inputs of Tap Domains 104 . TCK signal 740 clocks the Tap Domains 104 to respond to the TDI and TMS pattern 730 from update register 704 . The above described serial pattern shift in, parallel pattern update, and Tap Domain clock operation repeats as long as the CLK input 310 is active.
[0091] When the Tap Domain 104 receives a TCK input, the Tap state machine of the Tap Domain responds to the TMS input to perform state transitions as seen in FIG. 10 . Also the Tap Domain 104 will input data from its TDI input and output data on its TDO output in response to a TCK input, if the Tap state machine is in the Shift-DR/IR state of FIG. 10 .
[0092] FIG. 8A illustrates an example implementation of controller 700 . Controller 700 consists of FF 800 , FF 802 , AND gates 804 and 806 , and OR gate 808 . FF 800 toggles its update enable (UPENA) output during each rising edge of CLK 310 . FF 802 stores the UPENA output of FF 800 at its clock enable (CKENA) output on each falling edge of CLK 310 . AND gate 804 outputs a high on its UCK output when UPENA is high, CLK is low, and the controller reset (CRST) output of OR gate 808 is high. AND gate 806 is gated on to pass its CLK 310 input to its TCK output whenever CKENA and CRST are high, otherwise the TCK output is forced low. OR gate 808 outputs a high on CRST whenever the CENA input from CS circuit 708 is high and/or the RST input from TSM 706 is high, otherwise CRST outputs a low. CKENA changes state on the falling edge of CLK 310 to allow AND gate 806 to be enabled prior to the rising edge of CLK 310 to allow for good clock gating operation at the TCK output.
[0093] The operation of controller 700 is illustrated in the timing diagram of FIG. 8B . While the CRST output of OR gate 808 is high, the controller 700 operates to periodically output the UCK and TCK signals in response to the CLK input 310 . As mentioned, the TCK signal times the operation of the Tap Domains 104 and the UCK signal causes the update register to load the parallel TDO and TMS pattern from SIPO 702 . On each rising edge of CLK 310 the update enable (UPENA) output of FF 800 toggles its state. On each falling edge of CLK 310 the CKENA output of FF 802 is set to the state of the UPENA input to FF 802 . An UCK output occurs each time LDENA is high and the CLK goes low. A CKIN output occurs each time CKENA is high and the CLK is high. If CENA and RST are both low, the CRST output of OR gate 808 will be low to reset controller 700 . While CRST is low, the UPENA output of FF 800 is set high, the CKENA output of FF 802 is set low, the UCK output of AND gate 804 is set low, and the TCK output of AND gate 806 is set low.
[0094] FIG. 9A illustrates an example implementation of the MRS circuit 708 . MRS circuit 708 consists of a state machine 900 and a FF 902 . The state machine 900 operates on the rising edge of CLK 310 and FF 902 operates on the falling edge of CLK 310 . The state machine 900 inputs the IN signal from I/O circuit 710 , the RST signal from TSM 706 , a clock signal from CLK 310 , and a power on reset signal from POR 712 . The state machine 900 outputs the previously mentioned MRST signal and a controller enable (CE) signal. The CE signal is connected to the D input of FF 902 . The Q output of FF 902 drives the previously mentioned CENA signal. The reset input of the FF 902 is connected to the power on reset output of POR 712 .
[0095] As previously mentioned the purposes of the MRS circuit 708 are to maintain the SPC and Tap Domains in a reset condition when the SPC's DIO 308 signal is not externally driven and to synchronize the operation of the SPC with an external circuit driving the SPC's DIO 308 signal.
[0096] The operation of state machine 900 is shown in the state diagram of FIG. 9B . In response to a low active power on reset input from POR 712 or in response to the RST output of TSM 706 going low, the state machine 900 will enter “Set MRST Low & Poll IN” state 904 . In state 904 the state machine will output a low on the MRST output signal. The state machine will remain in state 904 while the IN input from I/O circuit 710 is high. The state machine will transition to “Poll IN” state 906 if the IN input goes low. The MRST output remains low in state 906 . The state machine will return to state 904 from state 906 if the IN input goes high, otherwise the state machine will transition from state 906 to “Poll IN” state 908 . The MRST output remains low in state 908 . The state machine will return to state 904 from state 908 if the IN input goes low, otherwise the state machine will transition from state 908 to “Poll IN” state 910 . The MRST output remains low in state 910 . The state machine will return to state 904 from state 910 if the IN input goes low, otherwise the state machine will transition from state 910 to “Set MRST & CE High” state 912 .
[0097] In state 912 , the state machine sets the MRST and CE signals high. On the falling edge of CLK 310 , FF 902 clocks in the high CE output from state machine 900 which sets the CENA output of FF 902 high. The state machine will remain in state 912 while the RST input is low. When the RST input goes high, the state machine will transition to the “Set CE Low” state 914 . In state 914 , the state machine sets the CE signal low. On the falling edge of CLK 310 , FF 902 clocks in the low CE output from state machine 900 which sets the CENA output of FF 902 low. The state machine will remain in state 914 while the RST input is high and will transition to state 904 when the RST input goes low.
[0098] The state machine is designed to enter state 904 when it receives a power on reset input from POR 712 or a low input on the RST output of TSM 706 . The state machine will remain in state 904 as long as the IN input from I/O circuit 710 is high. As will be described later in regard to FIG. 11A , I/O circuit is designed to output a high on the IN signal when the state machine outputs a low on the MRST signal and if the DIO input 308 to I/O circuit 710 is not being externally driven. The high on the IN signal maintains the state machine 900 in state 904 which maintains a low on the state machine MRST output. While MRST is low, SPC 306 circuitry and Tap Domains 104 are held in an inactive reset state that cannot interfere with the normal operation of the target IC.
[0099] When the JTAG controller 100 and PSC circuit 302 of FIG. 5A are first connected to the DIO signal of the target IC's SPC circuit 306 of FIG. 7A , the operation of the PSC and SPC circuits need to be synchronized such that the serialized TMS and TDO patterns from the PSC are correctly input as serialized TMS and TDO patterns to the SPC. The states within section 916 of the state diagram of FIG. 9B provide one example of how this required synchronization step may be achieved. A timing diagram depicting this synchronization process is shown in FIG. 9C .
[0100] Time reference 918 of FIG. 9C indicates a time period where the PSC 302 is not connected to SPC 306 , i.e. DIO 308 is not being externally driven. The circuitry in the SPC 306 and Tap Domains 104 of the target IC have been initialized as previously described and the state machine 900 is in state 904 polling the high output of the IN signal and outputting a low on the MRST output. Time 918 could be a time where the target IC in which the SPC 306 and Tap Domains 104 reside is operating normally in a system and the SPC's DIO signal is not being externally driven to perform test, emulation, debug, and/or trace operations. In this timing example it is assumed that CLK signal 310 is being actively driven by a clock source within the target IC. Thus state machine 900 state 904 is polling the high logic level of the IN signal during each rising edge of the active CLK signal 310 . It is worth noting that if the IN signal were to temporarily go low during a CLK cycle input for some unknown reason, the state machine would return to state 904 via state 906 . Further, the state machine would return to state 904 from states 908 and 910 in response to the IN signal having other temporarily low and high signal sequences for some unknown reason.
[0101] Time reference 920 of FIG. 9C indicates a time period where the PSC 302 has been externally connected to the SPC 306 via the DIO 308 and CLK 310 signals. During the physical connection process there may be undesirable temporary signaling sequence on DIO 308 due to the electrical connection being formed between the PSC and SPC. These temporary signal sequences could prevent the successful synchronization between the PSC and SPC. The state transition mapping in section 916 of FIG. 9B is provided to filter out the following three types of temporary signal sequences on the DIO so that they do not affect the synchronization process between PSC and SPC.
[0102] (1) As seen in the state diagram, a temporary DIO signal sequence of 1-0-1 during the connection process would cause the state machine to transition from state 904 to state 906 and back to state 904 . Thus this temporary DIO connection sequence is prevented from affecting the synchronization process.
[0103] (2) As seen in the state diagram, a temporary DIO signal sequence of 1-0-0-0-1 during the connection process would cause the state machine to transition from state 904 to state 906 to state 908 and back to state 904 . Thus this temporary DIO connection sequence is prevented from affecting the synchronization process.
[0104] (3) As seen in the state diagram, a temporary DIO signal sequence of 1-0-0-1-0-1 during the connection process would cause the state machine to transition from state 904 to state 906 to state 908 to state 910 and back to state 904 . Thus this temporary DIO connection sequence is prevented from affecting the synchronization process.
[0105] It should be understood that while the example state machine has been designed to filter out the above three types of temporary DIO sequences, it could be designed to filter out a greater number of DIO sequences if desired.
[0106] Time reference 922 of FIG. 9C indicates the start of a time period where the connection between the PSC 302 and SPC 306 has been made and the state machine is in state 904 with the IN signal driven high by DIO input from the connect PSC 302 . The PSC 302 begins the synchronization process by serially inputting a pattern of two logic 0's 924 on the SPC's IN signal via DIO 308 , which causes the state machine 900 to transition from state 904 to state 906 to state 908 . As seen in FIG. 5A , the PSC outputs the two logic 0's by loading the PISO 502 with a TMS value of 0 and a TDO value of 0 using the LD signal, then shifting the PISO to output the two logic 0's using the CLK signal 310 . Next the PSC 302 serially inputs a pattern of two logic 1's 926 on the SPC's IN signal via DIO 308 , which causes the state machine 900 to transition from state 908 to state 910 to state 912 . Again as seen in FIG. 5A , the PSC outputs the two logic 1's by loading the PISO 502 with a TMS value of 1 and a TDO value of 1 using the LD signal, then shifting the PISO to output the two logic 1's using the CLK signal 310 . As seen, the state machine 900 can only transition from state 904 to state 912 in response to the exact input of a serial pattern of two logic 0's followed by a serial pattern of two logic 1's.
[0107] As seen in the timing diagram, the MRST and CE signal outputs of state machine 900 are set high in state 912 at time 925 . MRST going high removes the reset condition from Tap Domains 104 , TSM 706 , and update register 704 . CE going high causes FF 902 to set CENA high at time 927 . When CENA goes high, the CRST signal of controller 700 is set high which enables the controller 700 to start outputting UCK and TCK signals at time 923 . The first UCK signal at time 923 loads the two logic 1's of pattern 926 into update register 704 . The enabling of the SPC's controller 700 at time 923 occurs such that the UCK and TCK signals of the SPC's controller 700 are synchronized with the LD and CKIN signals of the PSC's controller 500 , respectively. By synchronizing the UCK signal with the LD signal and the TCK signal with the CKIN signal the SPC 306 can correctly receive subsequent serialized two bit patterns from PSC 302 via DIO 308 . For example, when the PISO 502 is shifting out a two bit pattern the SIPO 702 is shifting in the two bit pattern, and when the PISO 502 is loading the next two bit pattern to be shifted the SIPO 702 is updating the current two bit pattern to the update register 704 . The synchronized operation of the UCK and LD signals and the TCK and CKIN signals will be seen more clearly in regard to the description of FIG. 14A .
[0108] While state machine 900 of the present disclosure has been designed to use a sequence of two serialized two bit patterns 924 and 926 for synchronization, it could be designed to use a longer sequence of serialized two bit patterns for synchronization if desired. Using a longer sequence of two bit patterns would further reduce the possibility of synchronization failure between the PSC and SPC due to the previously mentioned connection process during time 920 . Also a longer synchronization pattern sequence would improve the state machine's 900 ability to return to state 904 , when DIO is not externally driven, in the event unexpected signaling were to occur on the state machine's IN input. While the example two bit patterns 924 and 926 used two 0's and two 1's respectively, the two bits of a pattern may use any desired or necessary combinations of 0's and 1's as well. The TMS portion of the last two bit pattern of a pattern sequence will be the first TMS input the Tap Domains 104 and TSM circuit 706 respond to. In the FIG. 9C example, the TMS portion of pattern 926 was set to logic 1 to cause the Tap Domains 104 and TSM circuit 706 to remain in the TLR state following synchronization. If the TMS portion of pattern 926 had been set to logic 0, the Tap Domains 104 and TSM circuit 706 would have transitioned to the RTI state following synchronization.
[0109] Following the above described PSC and SPC synchronization process, the PSC may begin inputting serialized TDO and TMS patterns to the SPC to scan JTAG instructions or data into the Tap Domains 104 . The following example describes the PSC inputting serialized TDO and TMS patterns to the SPC to cause the Tap Domains 104 to perform an instruction scan operation according to the Tap state diagram of FIG. 10 .
[0110] The SPC inputs a first serialized TDO (X) and TMS ( 0 ) pattern 928 from the PSC which is input to SIPO 702 and applied to the TDI and TMS input Tap Domains 104 and the TMS input of TSM 706 via update register 704 during UCK 929 . The X in the TDO portion of the pattern indicates that TDO is a “don't care” signal. This first TDI and TMS pattern input to Tap Domains 104 and TSM 706 causes the Tap Domains and TSM to transition from the Test Logic Reset (TLR) state to the Run Test/Idle (RTI) state ( FIG. 10 ) in response to TCK 942 . On the falling edge of TCK 942 the TSM 706 sets its RST signal high to remove the reset condition at the input of OR gate 808 of controller 700 . In response to RST going high, state machine 900 transitions to state 914 on the next rising edge of CLK 310 . The state machine sets the CE output low in state 914 which causes FF 902 to output a low on CENA on the falling edge of CLK 310 . State machine 900 will remain in state 914 while the RST signal is high.
[0111] The SPC inputs a second serialized TDO (X) and TMS ( 1 ) pattern 930 from PSC which is input to SIPO 702 and applied to the TDI and TMS input Tap Domains 104 and the TMS input of TSM 706 via update register 704 during UCK 931 . This second TDI and TMS pattern causes the Tap Domains 104 and TSM to transition from the RTI state to the Select-DR (SLD) state in response to TCK 944 .
[0112] The SPC inputs a third serialized TDO (X) and TMS ( 1 ) pattern 932 from PSC which is input to SIPO 702 and applied to the TDI and TMS input Tap Domains 104 and the TMS input of TSM 706 via update register 704 during UCK 933 . This third TDI and TMS pattern causes the Tap Domains 104 and TSM to transition from the SLD state to the Select-IR (SLI) state in response to TCK 946 .
[0113] The SPC inputs a fourth serialized TDO (X) and TMS ( 0 ) pattern 934 from PSC which is input to SIPO 702 and applied to the TDI and TMS input Tap Domains 104 and the TMS input of TSM 706 via update register 704 during UCK 935 . This fourth TDI and TMS pattern causes the Tap Domains 104 and TSM to transition from the SLI state to the Capture-IR (CPI) state in response to TCK 948 .
[0114] The SPC inputs a fifth serialized TDO ( 0 ) and TMS ( 0 ) pattern 936 from PSC which is input to SIPO 702 and applied to the TDI and TMS input Tap Domains 104 and the TMS input of TSM 706 via update register 704 during UCK 937 . This fifth TDI and TMS pattern causes the Tap Domains 104 and TSM to transition from the CPI state to the Shift-IR (SHI) state in response to TCK 950 . When the TSM 706 transitions to the SHI state it's OE output is set to enable the output drive of I/O circuit 710 such that the first TDO output from the Tap Domains 104 can be output on DIO 308 to be input to the JTAG controller's TDI input via I/O circuit 504 of PSC controller 500 . TSM 706 sets its OE to enable the output drive of I/O circuit 710 whenever the TSM (and Tap Domains) is in the Shift-IR or Shift-DR states of FIG. 10 .
[0115] The SPC inputs a sixth serialized TDO ( 1 ) and TMS ( 0 ) pattern 938 from PSC which is input to SIPO 702 and applied to the TDI and TMS input Tap Domains 104 and the TMS input of TSM 706 via update register 704 during UCK 939 . This sixth TDI and TMS pattern causes the Tap Domains 104 and TSM to remain in the SHI state in response to TCK 952 . In pattern 938 , TDO is shown set to a 1 to indicate that the first TDI input to be shifted into the Tap Domains 104 is a logic 1. On the rising edge of TCK 952 the first TDI input (1) of the sixth pattern 938 is shifted into the Tap Domains 104 . Also the first TDO output from the TAP Domains 104 is input to the TDI input of the JTAG controller 100 on the rising edge of a CKIN input which is synchronized to TCK 952 .
[0116] For as long as serialized patterns ( 940 , 942 , . . . ) are input to cause the Tap Domains 104 (and TMS 706 ) to remain in the SHI state (i.e. TMS portion of the patterns=0), the TDI input portion of each pattern will be input to the Tap Domains 104 while TDO outputs from the Tap Domains will be input to the JTAG controller 100 . When the shifting in and out of TDI and TDO is complete, the PSC will input serialized patterns with the TMS portion of the patterns set to move the Tap Domains 104 and TMS 706 from the Shift-IR state (SHI) to the Exit1-IR state, then to any other state according to the Tap state diagram of FIG. 10 .
[0117] While the above process described performing an instruction scan operation between the JTAG controller and Tap Domains of the target IC, data scan operations may be similarly performed. Instruction and data scan operations using serialized TDI and TMS inputs from the JTAG controller and TDO outputs from the Tap Domains can be used to perform test, emulation, debug, trace, and/or other operations via the two signal DIO 308 and CLK 310 interface between the PSC and SPC.
[0118] When an operation is complete, the JTAG controller can output a string of serialized TDO and TMS patterns with the TMS portion of each pattern set to a logic one to cause the Tap Domains 104 and the TSM circuit 706 to transition into the Test Logic Reset state of FIG. 10 . As seen in FIG. 10 , the Tap state machine is designed to transition from any of its states to the Test Logic Reset state whenever it receives at least 5 logic high inputs on TMS. Therefore 5 serialized TDO and TMS patterns each with TMS high will cause the Tap Domains 104 and TSM 706 to enter the Test Logic Reset state.
[0119] When the TSM 706 enters the Test Logic Reset state it will set the RST output low which will reset the controller 700 and cause the MRS 708 state machine 900 to enter state 904 , which will result in the signal levels shown during time reference 918 of the timing diagram of FIG. 9C . After the SPC circuitry has been reset by the RST signal the DIO and CLK connection between the PSC and SPC can be removed. During the PSC and SPC disconnect step, temporary signal glitching/bounce may occur on the DIO signal. The previously described state machine 900 states in section 916 of FIG. 9B come into play once again to filter the IN input to the state machine such that the state machine remains in or returns to state 904 following any undesired temporary DIO signaling that may occur during the disconnect step. Following the disconnect step, the state machine will be in state 904 with the MRST output low, which maintains a reset condition on controller 700 , TSM 706 , and Tap Domains 104 .
[0120] FIG. 11A illustrates an example of a JTAG controller 100 and PSC 302 arrangement 1100 interfaced the SPC 306 and Tap Domains 104 of target IC 300 via DIO 308 signal connections between I/O circuit 504 of arrangement 1100 and I/O circuit 710 of the target IC. For simplification, the CLK 310 signal that accompanies the DIO signal 308 is not shown in this example. Also for simplification and ease of description, the I/O circuits 504 and 710 are shown to exist outside the PSC 302 and SPC 306 respectively, instead of inside as previously shown in FIGS. 5A and 7A . I/O circuit 504 is coupled to the PSC 302 via the OUT signal and to the JTAG controller 100 via the TDI signal. I/O circuit 710 is coupled to the Tap Domains 104 via the TDO signal and to the SPC via the IN and OE signals.
[0121] I/O circuit 504 consists of an input circuit 1102 , an output buffer 1104 , and a resistor 1106 . The OUT signal is coupled to the input of buffer 1104 and to a first input of the input circuit 1102 . The output of the buffer 1104 is coupled to the DIO signal via resistor 1106 . The DIO signal is coupled to a second input of the input circuit 1102 . The output of the input circuit 1102 is coupled to the TDI input of the JTAG controller 100 .
[0122] I/O circuit 710 consists of an input circuit 1108 , an output buffer 1110 , a resistor 1112 , and a pull up (PU) circuit 1114 . The TDO signal is coupled to the input of buffer 1110 and to a first input of the input circuit 1108 . The output of the buffer 1110 is coupled to the DIO signal via resistor 1112 . The DIO signal is coupled to a second input of the input circuit 1108 and to the PU circuit 1112 . The output of the input circuit 1108 is coupled to the IN input of SPC 306 .
[0123] The PU circuit 1114 is used to set the DIO signal input to input circuit 1108 high when the DIO signal is not being driven by either buffer 1104 or 1110 . For example, when the JTAG controller and PSC arrangement 1100 is not connected to the DIO of the target IC and while the output drive of buffer 1110 of the target IC is disabled by the OE signal, the PU circuit 1114 will set the DIO signal high so that logic ones are input to the SPC 306 from the IN signal output of input circuit 1108 high. The high on the IN signal will cause the state machine 900 of MRS circuit 708 to remain in state 904 of FIG. 9B , as previously described.
[0124] The output buffer 1104 of I/O circuit 504 and the output buffer 1110 of I/O circuit 710 will preferably be designed to have approximately the same current sink/source drive strength. Also the resistors 1106 and 1112 of I/O circuits 504 and 710 will have approximately the same resistance.
[0125] FIG. 11B illustrates timing waveforms for the four cases A-D in which simultaneous data communication occurs between the I/O circuits 504 and 710 via DIO 308 . Each case A-D is indicated in the timing diagram by vertical dotted line boxes. FIG. 12 illustrates the current flow on the DIO signal wire during each of the four cases A-D. In these examples, the OE input to buffer 1110 is set to enable the buffer 1110 to drive the DIO signal.
[0126] Case A shows PSC 302 driving OUT low and Tap Domains 104 driving TDO low. As seen in Case A of FIG. 12 , with lows being output from both buffers 1104 and 1110 only a small amount of current flows on the DIO signal wire. This small current flow does not develop a significant voltage drop across resistors 1106 and 1112 . Thus the DIO signal input to the input circuits 1102 and 1108 will be easily detectable as being a low signal input. In response to this OUT and TDO output condition the DIO signal is driven low. With OUT and DIO low, the input circuit 1102 inputs a low on the TDI input to JTAG controller 100 . With TDO and DIO low, the input circuit 1108 inputs a low on the IN input to SPC 306 .
[0127] Case B shows PSC 302 driving OUT low and Tap Domains 104 driving TDO high. As seen in Case B of FIG. 12 , with a low being output from buffer 1104 and a high being output from buffer 1110 a larger current flows between the buffers on the DIO signal wire. The resistors 1106 and 1112 serve to limit this larger current flow and the voltage drops developed across them establish mid level voltage on the DIO wire that is easily detectable by the input circuits 1102 and 1108 from being either high or low. In response to this OUT and TDO output condition the DIO signal is driven to a mid voltage level. With OUT low and DIO at a mid voltage, the input circuit 1102 inputs a high on the TDI input to JTAG controller 100 . With TDO high and DIO at a mid voltage, the input circuit 1108 inputs a low on the IN input to SPC 306 .
[0128] Case C shows PSC 302 driving OUT high and Tap Domains 104 driving TDO low. As seen in Case C of FIG. 12 , with a high being output from buffer 1104 and a low being output from buffer 1110 a larger current flows between the buffers on the DIO signal wire. The resistors 1106 and 1112 serve to limit this larger current flow and the voltage drops developed across them establish mid level voltage on the DIO wire that is easily detectable by the input circuits 1102 and 1108 from being either high or low. In response to this OUT and TDO output condition the DIO signal is driven to a mid voltage level. With OUT high and DIO at a mid voltage, the input circuit 1102 inputs a low on the TDI input to JTAG controller 100 . With TDO low and DIO at a mid voltage, the input circuit 1108 inputs a high on the IN input to SPC 306 .
[0129] Case D shows PSC 302 driving OUT high and Tap Domains 104 driving TDO high. As seen in Case D of FIG. 12 , with highs being output from both buffers 1104 and 1110 only a small amount of current flows on the DIO signal wire. This small current flow does not develop a significant voltage drop across resistors 1106 and 1112 . Thus the DIO signal input to the input circuits 1102 and 1108 will be easily detectable as being a high signal input. In response to this OUT and TDO output condition the DIO signal is driven high. With OUT and DIO high, the input circuit 1102 inputs a high on the TDI input to JTAG controller 100 . With TDO and DIO high, the input circuit 1108 inputs a high on the IN input to SPC 306 .
[0130] FIG. 13A illustrates one example of how to design an input circuit 1300 that can be used as either an input circuit 1102 or 1108 . The input circuit 1300 includes a voltage comparator circuit 1302 , a multiplexers 1304 , an inverter 1306 , and a buffer 1308 . The voltage comparator circuit 1302 inputs voltages from DIO and outputs digital control signals S 0 and S 1 to multiplexer 1304 . As seen, a first voltage (V) to ground (G) leg 1310 of voltage comparator circuit 1302 comprises a series P-channel transistor and a current source and a second voltage to ground leg 1312 comprises a series N-channel transistor and a current source. As seen, S 1 is connected at a point between the P-channel transistor and current source of the first leg 1310 and S 0 is connected at a point between the N-channel transistor and current source of the second leg 1312 . The gates of the transistors are connected to DIO to allow voltages on DIO to turn the transistors on and off.
[0131] The operation of the voltage comparator circuit 1302 and multiplexer 1304 is shown in the truth table of FIG. 13B and described herein. If the voltage on DIO is low, the S 0 and S 1 outputs are set high, which causes the multiplexer 1304 to select its low input 1314 and output the low input on the TDI/IN (TDI for circuit 1102 and IN for circuit 1108 ) signal via buffer 1308 . If the voltage on DIO is at a mid level, the SO is set low and the S 1 is set high, which causes the multiplexer 1304 to select its inverted OUT/TDO (OUT for circuit 1102 and TDO for circuit 1108 ) input signal 1316 and output the inverted OUT/TDO signal to the TDI/IN signal via and buffer 1308 . If the voltage on DIO is high, the S 0 and S 1 outputs are set low, which causes the multiplexer 1304 to select its high input 1318 and output the high input to the TDI/IN signal via and buffer 1308 .
[0132] From the above description it is clear that the input circuit 1300 will; (1) input a low on TDI/IN if the DIO signal is low, (2) input a high on TDI/IN if the DIO signal is high, and (3) will input the inverse of OUT/TDO on TDI/IN if the DIO signal is at a mid level voltage between high and low.
[0133] Referring back to FIG. 11A and in reference to the above description of input circuit 1300 it is clear that,
[0134] (1) If DIO is high, input circuits 1102 and 1108 will input highs to the JTAG controller 100 and SPC 306 respectively.
[0135] (2) If DIO is low, input circuits 1102 and 1108 will input lows to the JTAG controller 100 and SPC 306 respectively.
[0136] (3) If DIO is mid level and the OUT signal from PSC 302 is low, input circuit 1102 will know that the Tap Domain 104 is outputting a high on TDO to cause the mid level on DIO. Input circuit 1102 will therefore input a high to the TDI input of JTAG controller 100 .
[0137] (4) If DIO is mid level and the OUT signal from PSC 302 is high, input circuit 1102 will know that the Tap Domain 104 is outputting a low on TDO to cause the mid level on DIO. Input circuit 1102 will therefore input a low to the TDI input of JTAG controller 100 .
[0138] (5) If DIO is mid level and the TDO signal from Tap Domain 104 is low, input circuit 1108 will know that the PSC 302 is outputting a high on OUT to cause the mid level on DIO. Input circuit 1108 will therefore input a high to the IN input of SPC 306 ; and
[0139] (6) If DIO is mid level and the TDO signal from Tap Domain 104 is high, input circuit 1108 will know that the PSC 302 is outputting a low on OUT to cause the mid level on DIO. Input circuit 1108 will therefore input a low to the IN input of SPC 306 .
[0140] FIG. 14A shows a complete arrangement where the JTAG controller 100 and PSC 302 are connected to and are communicating with the SPC 306 and Tap Domains 104 of target IC 300 via the DIO 308 and CLK 310 signals. For simplification only the circuit elements of the PSC 302 and SPC 306 that are involved with the communication process are shown. The timing diagram of FIG. 14B details the communication process.
[0141] In the timing diagram of FIG. 14B , both the controllers 500 and 700 of PSC and SPC, respectively, have been synchronized as previously described and are actively operating their respective LD and CKIN and UCK and TCK signals in response to the CLK signal 310 . As seen and previously mentioned, the LD signal of the PSC operates synchronous with the UCK signal of the SPC, and the CKIN signal of the PSC operates synchronous with the TCK signal of the SPC. For simplification the CKIN and TCK signals are shown as one clock signal.
[0142] During LD signal 1402 TMS and TDO pattern N 1404 from JTAG controller 100 is loaded into PISO 502 . The TMS portion of the loaded pattern is shifted from PISO 502 to SIPO 702 during CLK 1406 and the TDO portion of the loaded pattern is shifted from PISO 502 to SIPO 702 during CLK 1408 . CKIN 1410 advances the JTAG controller to output the next TMS and TDO pattern N+1 1412 and to input the TDO output 1415 from the Tap Domains (if in the Shift-DR or Shift-IR state). TCK 1410 causes the TAP Domains 104 to respond to the previously transmitted TDI and TMS input pattern N−1 1414 input to the Tap Domains during UCK 1413 . Also during TCK 1410 , the Tap Domains will output the next TDO output to be input to the JTAG controller (if in the Shift-DR or Shift-IR state).
[0143] During LD signal 1418 TMS and TDO pattern N+1 1412 from JTAG controller 100 is loaded into PISO 502 . The TMS portion of the loaded pattern is shifted from PISO 502 to SIPO 702 during CLK 1420 and the TDO portion of the loaded pattern is shifted from PISO 502 to SIPO 702 during CLK 1422 . CKIN 1424 advances the JTAG controller to output the next TMS and TDO pattern N+2 1426 and to input the TDO output 1428 from the Tap Domains. TCK 1424 causes the TAP Domains 104 to respond to TDI and TMS input pattern N 1416 input to the Tap Domains during UCK 1413 . Also during TCK 1424 , the Tap Domains will output the next TDO output 1432 to be input to the JTAG controller.
[0144] The above described timing example of the communication between the JTAG controller 100 and Tap Domains 104 , via PSC and SPC, continues while a DIO and CLK connection exists between the PSC and SPC and while the CLK signal 310 is active.
[0145] FIG. 14C illustrates a timing example of the arrangement of FIG. 14A performing a single data register shift operation between the JTAG controller and Tap Domains. As seen the JTAG controller outputs a sequence of TMS and TDO patterns 1440 - 1454 that will control the Tap Domains to transition from the Run Test/Idle (RTI) state, to the Select-DR (SLD) state, to the Capture-DR (CPD) state, to the Select-DR (SLD) state, to the Exit1-DR (X1D) state, to the Update-DR (UPD) state, and back to the RTI state of FIG. 10 . This Tap state sequence will cause a one bit data register shift operation to occur between the JTAG controller and Tap Domains. The sequence of patterns 1440 - 1454 output from the JTAG controller is serialized by the PSC and de-serialized by the SPC to be input to the Tap Domains as TDI and TMS pattern sequences 1454 - 1468 . As seen the process of serializing and de-serializing the patterns causes TDI and TMS patterns input to the Tap Domains to lag behind the TMS and TDO patterns output from the JTAG controller.
[0146] If the JTAG controller were conventionally connected to the Tap Domains as seen in FIG. 1 , the TDO to TDI data shift operation between them would occur on the rising edge of the CKIN and TCK at time 1470 , i.e. when the Tap Domains transition from the Shift-DR (SFD) state to the Exit1-DR (X1D) state. However due to the pattern lag, the TDO to TDI data shift operation between them occurs on the rising edge of the CKIN and TCK at time 1472 . The shift in of the TDO data output from the JTAG controller to the TDI input of the Tap Domains is not effected by the pattern lag since the TDO data remains in the TDI and TMS pattern input to the Tap Domains following the serialization and de-serialization process and is clocked into the Tap Domains on the rising edge of TCK 1472 . However, the JTAG controller will not input the correct TDO output from the Tap Domains on the rising edge of CKIN 1470 since, due to the pattern lag, the correct TDO output (shown as dark filled) from the Tap Domains is not output from the Tap Domains until the falling edge of TCK 1470 . Thus while TDO data from the JTAG controller is correctly input as TDI date to the Tap Domains, the TDO output from the Tap Domains is incorrectly input as TDI data to the JTAG controller.
[0147] JTAG controllers that are designed using Texas Instruments SN74/54ACT8990 JTAG bus controller chips can resolve the above mentioned pattern lag problem. The SN74/54ACT8990 JTAG bus controller chips were designed to operate with cabling between JTAG controllers and target ICs that can register the TMS and TDO outputs from the JTAG controller to the TMS and TDI inputs of the target IC.
[0148] FIG. 15 illustrates an arrangement whereby the ACT8990 JTAG controller chip 1502 is interfaced to a target IC 1520 via a cable 1514 that includes FFs 1516 - 1518 in the path between the ACT8990's TMS and TDO outputs and the target IC's TMS and TDI inputs. In this example the target IC sources the CKIN to the ACT8990 and also times the operation of FFs 1516 and 1518 . As seen, the FFs 1516 and 1518 cause the TMS and TDI inputs to the target IC to lag the TMS and TDO output from the ACT8990 similar to the way the PSC and SPC circuits of FIG. 14A cause the TMS and TDI inputs to IC 300 to lag the TMS and TDO output of the JTAG controller 100 in FIG. 14A .
[0149] A simplified block diagram of the ACT8990 shows it containing a circuit 1504 for transmitting the TMS signal, a circuit 1506 for transmitting the TDO signal, a circuit 1510 from receiving the TDI signal, and a circuit 1508 for delaying the TMS signal 1512 input to the TDI receiver circuit 1510 . The TDI receiver circuit responds to the TMS signal 1512 , as per the Tap state diagram of FIG. 10 , to know when to input the TDI signal. In this example, all the circuits 1504 - 1510 are timed by the CKIN input from the TCK output of IC 1520 .
[0150] If no FFs existed in the cable, i.e. TMS and TDO output of the ACT8990 were directly connected to TMS and TDI inputs of the target IC, the TMS delay circuit would be set to not delay the TMS signal input to the TDI receiver. In this case the TDI receiver 1510 operates in step with the Tap of the target IC 1520 such that TDI receiver 1510 inputs TDI data at the same time that the Tap of IC 1520 inputs TDI data.
[0151] If the FFs existed in the path as shown, the TMS delay circuit is set to delay the operation of the TDI receiver for one CKIN cycle to allow the operation of the TDI receiver to be synchronized with the operation of the Tap of IC 1520 . By delaying the operation of the TDI receiver, the TDI receiver is made to operate in step with the delayed operation of the Tap of target IC 1520 such that TDI receiver 1510 inputs TDI data at the same time that the Tap of IC 1520 inputs TDI data.
[0152] While the delay circuit 1508 of the ACT8990 JTAG bus controller chip was originally designed to compensate for delays associated with cables, the present disclosure utilizes the delay circuit 1508 feature to compensate for the delay associated with the serialization and de-serialization operation of the PSC and SPC circuits in FIG. 14A .
[0153] For example, if the JTAG controller 100 of FIG. 14A used the ACT8990 chip to control the JTAG bus, the delay circuit 1508 of the ACT8990 could be set to delay the TDI input from the Tap Domains of IC 300 by one CKIN cycle such that the TDI input is correctly received on the rising edge of CKIN 1472 , as shown in the timing diagram of FIG. 14C . Thus the previously mentioned lag problem, due to the serialization and de-serialization process of the PSC and SPC circuits, is remedied by using JTAG controllers 100 that incorporate the ACT8990 JTAG bus controller chip or other chips/circuits that can similarly delay the inputting of TDI data from the Tap Domains 104 of FIG. 14A .
[0154] FIG. 16 illustrates a first system example wherein a JTAG controller 100 and PSC 302 arrangement 1602 is coupled to the SPC 306 and Tap Domains 104 of a target IC 1604 via DIO 308 and CLK 310 signal wiring. In this example a clock source 1606 within arrangement 1602 is used to drive the CLK signal that times the operation of the PSC and SPC circuits. In this example the target IC 1604 requires two dedicated pins for the DIO and CLK signals.
[0155] FIG. 17 illustrates a second system example wherein a JTAG controller 100 and PSC 302 arrangement 1702 is coupled to the SPC 306 and Tap Domains 104 of a target IC 1704 via DIO 308 and CLK 310 signal wiring. In this example a clock source 1706 within target IC 1704 is used to drive the CLK signal that times the operation of the PSC and SPC circuits. In this example the target IC 1704 requires two dedicated pins for the DIO and CLK signals.
[0156] FIG. 18 illustrates a third system example wherein a JTAG controller 100 and PSC 302 arrangement 1702 is coupled to the SPC 306 and Tap Domains 104 of a target IC 1802 via a DIO 308 signal wire. In this example an external clock source 1804 used to input a functional clock to IC 1802 via a functionally required clock input pin. The external clock source also drives the CLK signal of PSC 302 . Since the SPC 306 CLK input is connected to and driven by the IC's functional clock, a dedicated pin for the CLK signal 310 is not required on IC 1802 . In this example the target IC 1802 requires only a dedicated pin for the DIO signal.
[0157] FIG. 19 illustrates a fourth system example wherein a JTAG controller 100 and PSC 302 arrangement 1702 is coupled to the SPC 306 and Tap Domains 104 of a target IC 1802 via a DIO 308 signal wire. In this example a functional clock is output from IC 1902 to drive the clock input of a peripheral circuit 1904 via a functionally required clock output pin. Internal to the IC 1902 , the functional clock is connected to and drives the CLK input of SPC 306 . External of the IC 1902 , the functional clock is connected to and drives the CLK input of PSC 302 . Since the PSC 302 CLK input is connected to the external functional clock, a dedicated pin for the CLK signal 310 is not required on IC 1902 . In this example the target IC 1902 requires only a dedicated pin for the DIO signal.
[0158] FIG. 20 illustrates a fifth system example wherein a JTAG controller 100 and PSC 302 arrangement 1702 is coupled to the SPC 306 and Tap Domains 104 of a target IC 1604 via DIO 308 and CLK 310 signal wiring. In this example a clock source 2002 external of both arrangement 1702 and IC 1604 is used to drive the CLK signal that times the operation of the PSC and SPC circuits. In this example the target IC 1604 requires two dedicated pins for the DIO and CLK signals.
[0159] The above system examples of FIGS. 16-20 have shown various ways to interface the PSC and SPC circuits together such that at most the interface requires two dedicated IC pins for DIO and CLK and at least the interface only requires one dedicated pin for DIO. Thus the present disclosure is seen to require only one or two dedicated pins on the target IC.
[0160] The following Figures illustrate an alternate version of the present disclosure whereby the SPC 302 and PSC 306 circuits do not use I/O circuits 504 and 710 , respectively.
[0161] FIG. 21A illustrates a JTAG controller 100 interfaced to an alternate PSC circuit 2102 . The PSC circuit 2102 is identical to the PSC 302 of FIG. 5A with the exception that the I/O circuit 504 is not used in PSC circuit 2102 . As seen, without the I/O circuit 504 the OUT output from PISO 502 is directly output from the PSC via output buffer 1104 . Also as seen, without the I/O circuit 504 the TDO input goes directly to the TDI input of the JTAG controller 100 via an input buffer 1308 . As seen in FIG. 21B , the operation timing of the alternate PSC 2102 and JTAG controller 100 is identical to the FIG. 5B timing operation of the PSC 302 and JTAG controller 100 of FIG. 5A .
[0162] FIG. 22A illustrates an alternate SPC circuit 2202 interfaced to Tap Domains 104 of target IC 2204 . The SPC circuit 2202 is identical to the SPC 302 of FIG. 7A with the exception that the I/O circuit 710 is not used in SPC circuit 2202 . As seen, without the I/O circuit 710 the OUT input to SPC 2202 is directly input to the MRS 708 and SIPO 702 circuits via a second input buffer 1308 . Also as seen, without the I/O circuit 710 the TDO output from Tap Domains 104 is directly output from SPC 2202 via 3-state buffer 1110 . Buffer 2206 is enabled by the OE signal from TSM 706 . The pull up (PU) element 1114 is connected to the IN signal to pull the IN signal high when it is not being externally driven for reasons previously mentioned. As seen in FIG. 22B , the operation timing of the alternate SPC 2202 and Tap Domains 104 is identical to the FIG. 7B timing operation of the SPC 302 and Tap Domains 104 of FIG. 7A .
[0163] FIG. 23A shows a complete arrangement where the JTAG controller 100 and alternate PSC 2102 are connected to and are communicating with the alternate SPC 2202 and Tap Domains 104 of target IC 2302 via the OUT, CLK, and TDO signals. For simplification only the circuit elements of the alternate PSC 2102 and SPC 2202 that are involved with the communication process are shown. As seen the OUT output from PSC 2102 is directly input to the IN input of the SPC 2202 and the TDO output from Tap Domains 104 is directly input to the TDI input of JTAG controller 100 . As seen in FIG. 23B , the operation timing of the FIG. 3A arrangement is identical to the FIG. 14B timing operation of the FIG. 14A arrangement.
[0164] FIG. 24 illustrates the previously described clocking arrangement of the FIG. 16 system. In FIG. 24 , alternate PSC 2102 is used instead of PSC 302 and alternate SPC 2202 is used instead of SPC 306 . As seen, the IC 2402 requires three dedicated pins for OUT, TDO, and CLK.
[0165] FIG. 25 illustrates the previously described clocking arrangement of FIG. 17 system. In FIG. 25 , alternate PSC 2102 is used instead of PSC 302 and alternate SPC 2202 is used instead of SPC 306 . As seen, the IC 2502 requires three dedicated pins for OUT, TDO, and CLK.
[0166] FIG. 26 illustrates the previously described clocking arrangement of FIG. 18 system. In FIG. 26 , alternate PSC 2102 is used instead of PSC 302 and alternate SPC 2202 is used instead of SPC 306 . As seen, the IC 2602 requires two dedicated pins for OUT and TDO.
[0167] FIG. 27 illustrates the previously described clocking arrangement of FIG. 19 system. In FIG. 27 , alternate PSC 2102 is used instead of PSC 302 and alternate SPC 2202 is used instead of SPC 306 . As seen, the IC 2702 requires two dedicated pins for OUT and TDO.
[0168] FIG. 28 illustrates the previously described clocking arrangement of FIG. 20 system. In FIG. 28 , alternate PSC 2102 is used instead of PSC 302 and alternate SPC 2202 is used instead of SPC 306 . As seen, the IC 2402 requires three dedicated pins for OUT, TDO, and CLK.
[0169] The above system examples of FIGS. 24-28 have shown various ways to interface the alternate PSC 2102 and SPC 2202 circuits together such that at most the interface requires three dedicated IC pins for OUT, TDO and CLK, and at least the interface only requires two dedicated pin for OUT and TDO. Thus the alternate version of the present disclosure is seen to require only two or three dedicated pins on the target IC.
[0170] In reference to FIGS. 14A , 14 B, 14 C, 23 A, and 23 B it is seen that the frequency of the CKIN and TCK signals is one half the frequency of the source driving the CLK signal. Therefore the JTAG controller and the Tap Domains operate together at one half the frequency of the CLK sources. For example, if the CLK frequency is 100 Mhz, the JTAG operations will occur at 50 Mhz. Thus the second benefit of the present disclosure, stated in the DESCRIPTION OF THE RELATED ART section, of providing a reduced pin interface capable of operating at one half the frequency of the standard 5 pin JTAG interface is achieved.
[0171] It should be understood that while the SPC 306 and 2202 of the present disclosure has been shown as it would be used for accessing Tap Domains within ICs, the SPC is not limited to only accessing Tap Domains within ICs. Indeed, as the need may arise, the SPC can be used within embedded core circuits of an IC to allow accessing Tap Domains that exists within those embedded core circuits. The teaching in the present disclosure of how to use an SPC in an IC is sufficiently detailed to enable one skilled in the art to also use the SPC within an embedded core.
[0172] Although the present disclosure has been described in detail, it should be understood that various changes, substitutions, and alterations may be made without departing from the spirit and scope of the disclosure as defined by the appended claims.
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An optimized JTAG interface is used to access JTAG Tap Domains within an integrated circuit. The interface requires fewer pins than the conventional JTAG interface and is thus more applicable than conventional JTAG interfaces on an integrated circuit where the availability of pins is limited. The interface may be used for a variety of serial communication operations such as, but not limited to, serial communication related integrated circuit test, emulation, debug, and/or trace operations.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
REFERENCE TO A MICROFICHE APPENDIX
[0003] Not Applicable
FIELD OF INVENTION
[0004] The present invention relates to a device that allows a sitting person to adjust the direction and volume of the airflow from an air conditioning duct and more particularly, allows a passenger to control the direction and volume of the airflow from an air conditioning nozzle by manipulating a remote control keyboard located near the passenger.
BACKGROUND OF THE INVENTION
[0005] The ability of people to concentrate, to perform at work or to enjoy life to some extent is dependent upon their thermal comfort. Individual regulation of the thermal conditions at each occupant location is of great practical importance. A uniform room climate does provide a comfortable thermal environment for each occupant. Individual body heat transfer rates vary a great deal. It can vary due to differences in individual body heat production, different activities, the state of health of the individual, or their varying clothing habits. Therefore, a large room with a uniform room climate or an airplane fuselage is rarely simultaneously comfortable for all occupants. The varying comfort levels are accommodated by passenger adjustment of the direction and volume of air output by the supplemental air volume.
[0006] Air-conditioned rooms with constant temperature and air velocity lack that stimulatory effect achieved out of doors in a natural environment. Opening the windows of a small room will increase this stimulatory effect.
[0007] The total volume of conditioned air being fed into a room can be supplied in two distinct parts. A first part, called the primary air volume, establishes a basic room climate. The room air conditioning system provides a warm primary or “basic” overall room climate with low air velocity to accommodate a wide range of varying occupant needs. This type of system satisfies medical warnings against air streams impinging directly upon a small area of the body.
[0008] A second part, called the individual supplemental air volume, is introduced into the room by means of individually controlled adjustable air outlets. It allows for local or zonal climate adjustability that satisfies individual tastes and is distinct from the basic room climate.
[0009] Manually controlled air conditioning nozzles are employed on airliners and other means of transit to provide individual supplemental air volume. The nozzle is often located above and forward of the seat. A passenger must reach above their head and direct the nozzle and also adjust the volume of air passing through it. A short passenger or a passenger located near in an aisle seat must get up from their seat to perform the manual manipulation of the nozzle. The passenger must guess at the volume and direction settings because she is out of her seated position and is not able to feel the effect of these manipulations. The passenger often must repeat the adjustment process several times before reaching a satisfactory setting. This iterative process is uncomfortable for the passenger as well as and the neighboring passengers. Passengers typically perform this adjustment after locating their seat and stowing carry-on baggage. The neighboring passengers are also trying to locate their seat and stow their baggage. The passenger manipulation increases the amount of time required to get all of the passengers settled and ready for departure.
[0010] What is needed is a device that increases a passenger's thermal comfort through remote control of the direction and volume of the individual supplemental air at each seat. The device should also allow a local climate zone that is distinct from the basic room climate or condition.
BRIEF SUMMARY OF THE INVENTION
[0011] The invention resides in a remote controlled air conditioning nozzle. The remote controlled air conditioning nozzle includes a housing.
[0012] An air nozzle is also included. The air nozzle is spherically connected into the housing. The air nozzle has an air passageway with an input end and an output end. The input end has an outer surface. Conditioned air enters the input end and exits the output end.
[0013] At least one electric motor is provided. A means for spherically changing the output direction of the air nozzle is provided. The air nozzle has a means for changing the volume of air output. The means for spherically changing the output direction of the air nozzle is propelled by at least one electric motor. The means for changing the volume of air output is also propelled by the at least one electric motor.
[0014] A remote control is also included. The remote control directs the means for spherically changing the output direction of the air nozzle and the means for changing the volume of air output by the air nozzle.
[0015] In a variant of this invention, the remote control is located near the seat occupant.
[0016] In another variant of this invention, an air supply line is included. The air supply line brings air into the input end of the air nozzle.
[0017] In yet another variant of this invention, the outer surface of the input end of the air nozzle has a spherical contour.
[0018] In another variant of this invention, the means for spherically changing the output direction of the air nozzle further includes at least one pivot hinge. The at least one pivot hinge has a hinge pin and a hinge pin receiver. The hinge pin is disposed on the outer surface of the input end of the air nozzle. The hinge pin receiver is disposed on the housing. The hinge pin is installed into the hinge pin receiver such that the air nozzle can pivot on the at lease one pivot hinge.
[0019] In a variation of this invention, the housing has a sprocket. The sprocket has gear teeth evenly spaced around a circular outer perimeter. The sprocket has an inner perimeter. It also has an upper surface and a lower surface. The sprocket has at least one hinge pin receiver located on the inner perimeter. The air nozzle is disposed within the sprocket such that at least one hinge pin is installed into the at least one hinge pin receiver. The housing has a lower lip. The sprocket rests on ball bearings sandwiched between its lower surface and the lower lip of the housing. The sprocket is rotatable on the ball bearings. The sprocket rotates about a vertical axis running through the center of the circular outer perimeter. The sprocket receives rotational impetuous from the at least one electric motor.
[0020] Another variation of this invention further includes a first hinge pin and a second hinge pin located on the outer surface of the input end of the air nozzle. The sprocket has a first hinge pin receiver and a second hinge pin receiver located on the inner perimeter. The second hinge pin receiver is vertically offset from the first hinge pin receiver.
[0021] In again another variant of this invention, the means for spherically changing the output direction of the air nozzle further includes locating at least one groove pin on the outer surface of the input end of the air nozzle. At least one groove is located on the housing. The air nozzle is positioned within the housing such that the at least one groove pin slideably fits within the at least one groove.
[0022] In even another variant of this invention, the at least one groove is sinusoidal shaped and the at lease one groove pin is being pushed into the at least one groove by a spring.
[0023] In yet again another variation of this invention, the means for changing the volume of air output by the air nozzle includes a damper flap. The damper flap has at least one rotation pivot hinge. The damper flap is sized and shaped to rotate on the at least one rotation pivot hinge to change the volume of air entering the air nozzle.
[0024] In even another variation of this invention, the means for spherically changing the output direction of the air nozzle includes a bushing with a top surface and a central receiving hole. A coupler is provided. The coupler has a perimeter, a top surface, a bottom surface and a central rotation shaft. The perimeter of the coupler has evenly disposed gear teeth. The central rotation shaft has a centerline. A drive shaft is attached to an engager. The drive shaft has a centerline. The engager has a T shape. The central rotation shaft is installed through a biasing means and into and through the central receiving hole. The biasing means pushes against the bottom surface of the coupler and the top surface of the bushing. The coupler has at least one ramp with an end notch concentrically located on the top surface near the perimeter. The engager is shaped, sized and located such that the centerline of the drive shaft is co-linear to the centerline of the central rotation shaft when the engager is in contact with the at least one ramp. The at lease one ramp and end notch are disposed such that when the engager is rotated in a first direction, the engager locks against the end notch and rotates the coupler. The gear teeth of the coupler engage the gear teeth of the sprocket to impart rotation into the sprocket. Rotation of the sprocket causes the air nozzle to rotate on the first hinge pin and the second hinge pin and slide the at least one groove pin along the at least one groove, resulting in the spherical rotation the air nozzle. When the engager is rotated in the second direction, the engager rides up the at least one ramp pushing the coupler against the biasing means without locking against the end notch. The coupler does not rotate.
[0025] In even another variation of this invention, the means for changing the volume of air output by said air nozzle also includes a bushing with a top surface and a central receiving hole. A coupler is provided. The coupler has a perimeter, a top surface, a bottom surface and a central rotation shaft. A drive shaft is attached to an engager. The drive shaft has a centerline. The engager has a T shape. The central rotation shaft is installed through the biasing means and into and through the central receiving hole. The biasing means pushes against the bottom surface of the coupler and against the top surface of the bushing. The coupler has at least one ramp with an end notch concentrically located on the top surface near the perimeter. The engager is shaped, sized and located such that the centerline of the drive shaft is co-linear to the centerline of the central rotation shaft and the engager is in contact with the at least one ramp. The at least one ramp and end notch are disposed such that when the engager is rotated in a second direction, the engager locks against the end notch and rotates the coupler. A flexible shaft is connected to the end of the central rotation shaft that is sticking out through the central receiving hole of the bushing. The flexible shaft is connected concentrically to the at least one rotation pivot hinge of the damper flap. Rotation of the central rotation shaft results in a change in the volume of air output by the air nozzle. When the engager is rotated in the opposite direction, the engager pushes against the at least one ramp driving the coupler against the biasing means. The engager does not lock against the end notch. No rotation is imparted into the coupler.
[0026] The air nozzle is capable of seat occupant manual over-ride adjustment instead of remote controlled adjustment.
[0027] The invention also resides in a remote controlled air conditioning nozzle with three motors. The remote controlled air conditioning nozzle includes a housing.
[0028] An air nozzle is provided. The air nozzle has a first pivotal connection to the housing. The first pivotal connection has a first pivotal axis. The air nozzle has a second pivotal connection to the housing. The second pivotal connection has a second pivotal axis. The second pivotal axis is perpendicular to the first pivotal axis. The air nozzle has an air passageway with an input end and an output end. The input end has an outer surface. Conditioned air enters the input end and exits the output end.
[0029] A first motor is provided. The first motor is disposed to propel a first means for pivoting the air nozzle about the first pivotal connection.
[0030] A second motor is provided. The second motor is disposed to propel a second means for pivoting the air nozzle about the second pivotal connection.
[0031] A third motor is provided. The third motor is disposed to propel a means for changing the volume of air output by the air nozzle.
[0032] A remote control is provided. The remote control directs the first means for pivoting the air nozzle about the first pivotal connection, the second means for pivoting the air nozzle about the second pivotal connection and the changing of the volume of air output by the air nozzle.
[0033] In a variant of this invention, wherein the means for changing the volume of air output has a worm drive gear attached to the third motor. The worm receiver gear is disposed in relation to the damping device such that when driven by the worm gear, the volume of air output by the air nozzle changes.
[0034] In another variant of this invention, the air nozzle has a spherical outer surface region. The spherical outer surface region is cupped in a spherical socket in the housing thus forming a spherically pivotable connection.
[0035] In yet another variant of this invention, a swivel plate is sized, shaped and attached to the outer surface of the air nozzle such that the air nozzle is sandwiched between the swivel plate and the spherical socket. The swivel plate has a first corner, a second corner and a third corner.
[0036] In still another variant of this invention, the first motor and the means for pivoting the air nozzle about the first pivotal connection includes the first motor being connected by a gear means to the first corner of the swivel plate. The second motor and the means for pivoting the air nozzle about the second pivotal connection further comprises the second motor being connected by a gear means to the second corner of the swivel plate. The third corner is attached by a biasing means to the holding fixture. The first motor and or the second motor is directed by signals sent by the by the remote control to pivot the swivel plate while the third corner of the swivel plate is fixed by the biasing means resulting in the pivoting of the air nozzle while holding the spherical outer surface region in the cupping spherical socket.
[0037] In still another variant of this invention, the signals sent by the remote control are transmitted from a central electronic control board.
[0038] In again another variant of this invention, the swivel plate is orientated perpendicular to the direction of the output air.
[0039] In even another variant of this invention, the swivel plate has a planar shape.
[0040] In a variation of this invention, the biasing means is a spring.
[0041] The air nozzle is capable of seat occupant manual over-ride adjustment instead of remote controlled adjustment.
[0042] The foregoing has outlined the more pertinent and important features of the present invention in order that the detailed description of the invention that follows may be better understood so the present contributions to the art may be more fully appreciated. Additional features of the present invention will be described hereinafter, which form the subject of the claims. It should be appreciated by those skilled in the art that the conception and the disclosed specific embodiment may be readily utilized as a basis for modifying or designing other structures and methods for carrying out the same purposes of the present invention. It also should be realized by those skilled in the art that such equivalent constructions and methods do not depart from the spirit and scope of the inventions as set forth in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0043] The invention will be more fully understood by reference to the following drawings that are for illustrative purposes only:
[0044] [0044]FIG. 1 is a perspective view of an airline seat showing the location for the remote control device and the air nozzle;
[0045] [0045]FIG. 2 is a cross sectional view of the at least one motor incarnation of the invention;
[0046] [0046]FIG. 3 is a plan view of the air nozzle;
[0047] [0047]FIG. 4 is a vertical cross sectional view of the air nozzle;
[0048] [0048]FIG. 5 is the pattern formed by spherical rotation of the second end of the air nozzle during seat occupant manipulation of the invention;
[0049] [0049]FIG. 6 is a plan view of the sprocket;
[0050] [0050]FIG. 6 a is a side view of-the sprocket;
[0051] [0051]FIG. 7 is a side view of the housing;
[0052] [0052]FIG. 7 a is a plan view of the housing;
[0053] [0053]FIG. 8 is a magnified view of the sprocket-to-ball bearings-to-housing interface;
[0054] [0054]FIG. 9 is a magnified view of the lower engager-to-coupler interface;
[0055] [0055]FIG. 10 magnified view of the motor;
[0056] [0056]FIG. 11 is a magnified view of the upper engager-to-coupler interface;
[0057] [0057]FIG. 12 is a side view of the three motor incarnation of the invention;
[0058] [0058]FIG. 13 is an aircraft interior view of the air nozzle;
[0059] [0059]FIG. 14 is a plan view depicting each motor and each motors connection by a gear means to its respective corner of the swivel plate; and
[0060] [0060]FIG. 15 is a side view of the first motor and the first motor connection by a gear means to the first corner of the swivel plate.
DETAILED DESCRIPTION
[0061] The following description is provided for the purpose of describing an example and specific embodiment of the invention only and is not intended to exhaustively describe all possible examples and embodiments of the invention.
[0062] Referring more specifically to the drawings, the present invention is embodied in the apparatus generally shown in FIGS. 1 through 15.
[0063] The invention resides in a remote controlled air conditioning nozzle 10 . The remote controlled air conditioning nozzle includes a housing 14 .
[0064] As shown in FIG. 2, an air nozzle 18 is also included. The air nozzle 18 is spherically connected into the housing 14 . The air nozzle 18 has an air passageway with an input end 22 and an output end 26 . The input end 22 has an outer surface 28 . Conditioned air enters the input end 22 and exits the output end 26 .
[0065] At least one electric motor 30 is provided. A means for spherically changing the output direction of the air nozzle 34 is provided. The air nozzle has a means for changing the volume of air output 38 . The means for spherically changing the output direction of the air nozzle 34 is propelled by at least one electric motor 30 . The means for changing the volume of air output 38 is also propelled by the at least one electric motor 30 .
[0066] As shown in FIGS. 1 and 2, a remote control is also included 42 . The remote control 42 directs the means for spherically changing the output direction of the air nozzle 34 and the means for changing the volume of air output by the air nozzle 38 .
[0067] In a variant of this invention, the remote control 42 is located near the seat occupant.
[0068] In another variant of this invention, an air supply line is included. The air supply line brings air into the input end 22 of the air nozzle 18 .
[0069] In yet another variant of this invention, the outer surface 28 of the input end 22 of the air nozzle 18 has a spherical contour.
[0070] As shown in FIG. 2, another variant of this invention has the means for spherically changing the output direction of the air nozzle 34 further including at least one pivot hinge 46 . The at least one pivot hinge 46 has a hinge pin 50 and a hinge pin receiver 54 . The hinge pin 50 is disposed on the outer surface 28 of the input end 22 of the air nozzle 18 . The hinge pin receiver 54 is disposed on the housing 14 . The hinge pin 50 is installed into the hinge pin receiver 54 such that the air nozzle 18 can pivot on the at lease one pivot hinge 46 .
[0071] In a variation of this invention, shown in FIGS. 2, 6 and 8 , the housing 14 has a sprocket 66 . The sprocket 66 has gear teeth 74 evenly spaced around a circular outer perimeter 70 . The sprocket 66 has an inner perimeter 70 . It also has an upper surface and a lower surface 86 . The sprocket 66 has at least one hinge pin receiver 46 located on the inner perimeter 70 . The air nozzle 18 is disposed within the sprocket 66 such that at least one hinge pin 50 is installed into the at least one hinge pin receiver 54 . The housing 14 has a lower lip 90 . The sprocket 66 rests on ball bearings 94 sandwiched between its lower surface 86 and the lower lip 90 of the housing 14 . The sprocket 66 is rotatable on the ball bearings 94 . The sprocket 66 rotates about a vertical axis running through the center of the circular outer perimeter 70 . The sprocket 66 receives rotational impetuous from the at least one electric motor 30 .
[0072] Another variation of this invention, shown in FIGS. 2, 3, 4 and 6 , further includes a first hinge pin 98 and a second hinge pin 102 located on the outer surface 28 of the input end 22 of the air nozzle 18 . The sprocket 66 has a first hinge pin receiver 106 and a second hinge pin receiver 110 located on the inner perimeter 70 . The second hinge pin receiver 110 is vertically offset from the first hinge pin receiver 106 .
[0073] In again another variant of this invention, shown in FIGS. 2 and 7, the means for spherically changing the output direction of the air nozzle 34 further includes locating at least one groove pin 58 on the outer surface 28 of the input end 22 of the air nozzle 18 . At least one groove 62 is located on the housing 14 . The air nozzle 18 is positioned within the housing 14 such that the at least one groove 58 pin slideably fits within the at least one groove 62 .
[0074] In even another variant of this invention, the at least one groove 62 is sinusoidal shaped and the at lease one groove pin 58 is being pushed into the at least one groove 62 by a spring.
[0075] In yet again another variation of this invention, shown in FIGS. 2 and 7, the means for changing the volume of air output by the air nozzle 38 includes a damper flap 114 . The damper flap 114 has at least one rotation hinge 118 . The damper flap 114 is sized and shaped to rotate on the at least one rotation hinge 118 to change the volume of air entering the air nozzle 18 .
[0076] In even another variation of this invention, shown in FIGS. 2, 9 and 10 , the means for spherically changing the output direction of the air nozzle includes a bushing 122 with a top surface 126 and a central receiving hole 130 . A coupler 134 is provided. The coupler 134 has a perimeter 138 , atop surface 142 , a bottom surface and a central rotation shaft 150 . The perimeter 138 of the coupler 134 has evenly disposed gear teeth 154 . The central rotation shaft 150 has a centerline. A drive shaft 158 is attached to an engager 162 . The drive shaft 158 has a centerline. The engager 162 has a T shape. The central rotation shaft 150 is installed through a biasing means 166 and into and through the central receiving hole 130 . The biasing means 166 pushes against the bottom surface of the coupler 134 and the top surface 126 of the bushing 122 . The coupler 134 has at least one ramp 170 with an end notch 174 concentrically located on the top surface 142 near the perimeter 138 . The engager 162 is shaped, sized and located such that the centerline of the drive shaft 158 is co-linear to the centerline of the central rotation shaft 150 when the engager 162 is in contact with the at least one ramp 170 . The at lease one ramp 170 and end notch 174 are disposed such that when the engager 162 is rotated in a first direction, the engager 162 locks against the end notch 174 and rotates the coupler 134 . The gear teeth 154 of the coupler 134 engage the gear teeth 74 of the sprocket 66 to impart rotation into the sprocket 66 . Rotation of the sprocket 66 causes the air nozzle 18 to rotate on the first hinge pin 98 and the second hinge pin 102 and slide the at least one groove pin 58 along the at least one groove 62 , resulting in the spherical rotation the air nozzle 18 . When the engager 162 is rotated in the second direction, the engager 162 rides up the at least one ramp 170 pushing the coupler 134 against the biasing means 166 without locking against the end notch 174 . No rotation is imparted into the coupler 134 .
[0077] The means for spherically changing the output direction of the air nozzle moves the out put end of the air nozzle in the pattern shown in FIG. 5.
[0078] In even another variation of this invention, shown in FIGS. 2, 7 and 11 , the means for changing the volume of air output 38 by said air nozzle 18 also includes a bushing 178 with a top surface 182 and a central receiving hole 186 . A coupler 190 is provided. The coupler 190 has a perimeter 194 , a top surface 198 , a bottom surface and a central rotation shaft 206 . A drive shaft 210 is attached to an engager 214 . The drive shaft 210 has a centerline. The engager 214 has a T shape. The central rotation shaft 206 is installed through a biasing means 218 and into and through the central receiving hole 186 . The biasing means 218 pushes against the bottom surface of the coupler 190 and against the top surface 182 of the bushing 178 . The coupler 190 has at least one ramp 222 with an end notch 226 concentrically located on the top surface 198 near the perimeter 194 . The engager 214 is shaped, sized and located such that the centerline of the drive shaft 210 is co-linear to the centerline of the central rotation shaft 206 and the engager 214 is in contact with the at least one ramp 222 . The at least one ramp 222 and end notch 226 are disposed such that when the engager 214 is rotated in a second direction, the engager 214 locks against the end notch 226 and rotates the coupler 190 . A flexible shaft 230 is connected to the end of the central rotation shaft 206 that is sticking out through the bushing 178 central receiving hole 186 . The flexible shaft 230 is connected concentrically to the at least one rotation pivot hinge 118 of the damper flap 114 . Rotation of the central rotation shaft 206 results in a change in the damper flap 114 location and a change in the volume of air output by the air nozzle 18 . When the engager 214 is rotated in the opposite direction, the engager 214 pushes against the at least one ramp 222 driving the coupler 190 against the biasing means 218 . The engager 214 does not lock against the end notch 226 . No rotation is imparted into the coupler 134 .
[0079] The air nozzle 18 is capable of seat occupant manual over-ride adjustment instead of remote controlled adjustment.
[0080] The invention also resides in a remote controlled air conditioning nozzle 310 with three motors. The remote controlled air conditioning nozzle 310 includes a housing 314 .
[0081] As shown in FIGS. 12, 13, 14 and 15 , an air nozzle 318 is provided. The air nozzle 318 has a first pivotal connection 322 to the housing 314 . The first pivotal connection has a first pivotal axis. The air nozzle 318 has a second pivotal connection to the housing 314 . The second pivotal connection has a second pivotal axis. The second pivotal axis is perpendicular to the first pivotal axis. The air nozzle 318 has an air passageway with an input end 338 and an output end 342 . The input end 338 has an outer surface 342 . Conditioned air enters the input end 338 and exits the output end 342 .
[0082] A first motor 346 is provided. The first motor 346 is disposed to propel a first means for pivoting the air nozzle about the first pivotal connection 350 .
[0083] A second motor 354 is provided. The second motor 354 is disposed to propel a second means for pivoting the air nozzle about the second pivotal connection 358 .
[0084] A third motor 358 is provided. The third motor 358 is disposed to propel a means for changing the volume of air output 362 by the air nozzle 318 .
[0085] A remote control is provided. The remote control directs the first means for pivoting the air nozzle about the first pivotal connection 350 , the second means for pivoting the air nozzle about the second pivotal connection 358 and the changing of the volume of air output by the air nozzle 362 .
[0086] In a variant of this invention, wherein the means for changing the volume of air output 362 has a worm drive gear 366 attached to the third motor 358 . The worm receiver gear 366 is disposed in relation to the damping device 370 such that when driven by the worm gear 366 , the volume of air output by the air nozzle 318 changes.
[0087] In another variant of this invention, shown in FIGS. 12 and 15, the air nozzle 318 has a spherical outer surface region 374 . The spherical outer surface region 374 is cupped in a spherical socket 378 in the housing 324 thus forming the spherically pivotable connection 382 .
[0088] In yet another variant of this invention, shown in FIGS. 14 and 15, a swivel plate 386 is sized, shaped and attached to the spherical outer surface region 374 such that the air nozzle 318 is sandwiched between the swivel plate 386 and the spherical socket 374 . The swivel plate has a first corner 390 , a second corner 394 and a third corner 398 .
[0089] In still another variant of this invention, shown in FIGS. 14 and 15, the first motor 346 and the means for pivoting the air nozzle 350 about the first pivotal connection includes the first motor 346 being connected by a gear means 402 to the first corner 390 of the swivel plate 386 . The second motor 354 and the means for pivoting the air nozzle 358 about the second pivotal connection further comprises the second motor 354 being connected by a gear means 406 to the second corner 394 of the swivel plate 386 . The third corner 398 is attached by a biasing means 410 to a holding fixture 414 . The first motor 346 and or the second motor 354 is directed by signals sent by the a remote control 366 to pivot the swivel plate 386 while the third corner 318 of the swivel plate 386 is fixed by the biasing means 410 resulting in the pivoting of the air nozzle 318 while holding the spherical outer surface region 374 in the cupping spherical socket 378 .
[0090] In still another variant of this invention, the signals sent by the remote control 366 are transmitted from a central electronic control board 418 .
[0091] In again another variant of this invention, the swivel plate 386 is orientated perpendicular to the direction of the output air.
[0092] In even another variant of this invention, the swivel plate 386 has a planar shape.
[0093] In a variation of this invention, the biasing means 410 is a spring.
[0094] The air nozzle 318 is capable of seat occupant manual over-ride adjustment instead of remote controlled adjustment.
[0095] The present disclosure includes that contained in the present claims as well as that of the foregoing description. Although this invention has been described in its preferred forms with a certain degree of particularity, it is understood that the present disclosure of the preferred forms has been made only by way of example and numerous changes in the details of construction and combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention. Accordingly, the scope of the invention should be determined not only by the embodiments illustrated, but by the appended claims and their legal equivalents.
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The present invention provides a device that allows a sitting airline passenger to control the direction and volume of the airflow from an overhead air conditioning nozzle by manipulating a remote control keyboard located near the passenger. It increases an individual's thermal comfort in an aircraft cabin by allowing the individual to regulate the thermal conditions at their seat. The present invention also allows an individual-supplemental air volume to be introduced into an aircraft cabin by means of individual spreadable and adjustable air outlets to provide a “local” climate zone that is distinct from the basic cabin climate or condition. The present invention also provides a means of remote passenger manipulation of the individual-supplemental air volume and direction and all from the comfort of the passenger seat. The abstract is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
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This application claims the benefit of U.S. Provisional Application No. 60/785,419, filed on Mar. 24, 2006, and U.S. Provisional Application No. 60/786,471, filed on Mar. 27, 2006, all of which are hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of reducing overhead, and more particularly, to a method of reducing overhead for multi-input, multi-output (MIMO) transmission system.
2. Discussion of the Related Art
In the world of cellular telecommunications, those skilled in the art often use the terms 1G, 2G, and 3G. The terms refer to the generation of the cellular technology used. 1G refers to the first generation, 2G to the second generation, and 3G to the third generation.
1G refers to the analog phone system, known as an AMPS (Advanced Mobile Phone Service) phone systems. 2G is commonly used to refer to the digital cellular systems that are prevalent throughout the world, and include CDMAOne, Global System for Mobile communications (GSM), and Time Division Multiple Access (TDMA). 2G systems can support a greater number of users in a dense area than can 1G systems.
3G commonly refers to the digital cellular systems currently being deployed. These 3G communication systems are conceptually similar to each other with some significant differences.
In a wireless communication system, it is important to devise schemes and techniques that increase the information rate and improve the robustness of a communication system under the harsh conditions of the wireless environment. To combat less-than-ideal communication conditions and/or to improve communication, various methods, including reducing transmission of unnecessary data, can be used to free up resources as well as promote more effective and efficient transmission.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a method of reducing overhead for multi-input, multi-output (MIMO) transmission system that substantially obviates one or more problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a method of transmitting data in a multi input, multi output (MIMO) system.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a method of transmitting data in a multi input, multi output (MIMO) system includes selecting a primary antenna, based on satisfying at least one specified criteria, for transmitting a preamble, and transmitting the preamble via the primary antenna.
In another aspect of the present invention, a method of transmitting data in a multi input, multi output (MIMO) system includes selecting an antenna from a plurality of transmission antennas as a primary antenna based on the antenna having the best channel condition or a smallest index from the plurality of transmission antennas for transmitting at least one preamble, and transmitting at least one of the preamble and the data via the primary antenna.
In a further aspect of the present invention, a method of transmitting data in a multi input, multi output (MIMO) system includes selecting an antenna from a plurality of transmission antennas as a primary antenna based on the antenna having the best channel condition or a smallest index from the plurality of transmission antennas for transmitting at least one preamble, and transmitting at least one of the preamble and the data via the primary antenna.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings;
FIG. 1 illustrates wireless communication network architecture;
FIG. 2A illustrates a CDMA spreading and de-spreading process;
FIG. 2B illustrates a CDMA spreading and de-spreading process using multiple spreading sequences;
FIG. 3 illustrates a data link protocol architecture layer for a cdma2000 wireless network;
FIG. 4 illustrates cdma2000 call processing;
FIG. 5 illustrates the cdma2000 initialization state;
FIG. 6 illustrates the cdma2000 system access state;
FIG. 7 illustrates a comparison of cdma2000 for a 1x system and a 1xEV-DO system;
FIG. 8 illustrates a 1xEV-DO system architecture;
FIG. 9 illustrates 1xEV-DO default protocol architecture;
FIG. 10 illustrates 1xEV-DO non-default protocol architecture;
FIG. 11 illustrates 1xEV-DO session establishment;
FIG. 12 illustrates 1xEV-DO connection layer protocols;
FIG. 13 illustrates an exemplary diagram of a multiple antenna transmission architecture;
FIG. 14 is another exemplary diagram illustrating transmit diversity combined with antenna selection;
FIG. 15 is an exemplary diagram illustrating overhead reduction transmission;
FIG. 16 is an exemplary diagram illustrating transmission assuming preamble and OFDM data transmission; and
FIG. 17 is another exemplary diagram illustrating transmission of preamble and OFDM data.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
Referring to FIG. 1 , a wireless communication network architecture is illustrated. A subscriber uses a mobile station (MS) 2 to access network services. The MS 2 may be a portable communications unit, such as a hand-held cellular phone, a communication unit installed in a vehicle, or a fixed-location communications unit.
The electromagnetic waves for the MS 2 are transmitted by the Base Transceiver System (BTS) 3 also known as node B. The BTS 3 consists of radio devices such as antennas and equipment for transmitting and receiving radio waves The BS 6 Controller (BSC) 4 receives the transmissions from one or more BTS's. The BSC 4 provides control and management of the radio transmissions from each BTS 3 by exchanging messages with the BTS and the Mobile Switching Center (MSC) 5 or Internal IP Network. The BTS's 3 and BSC 4 are part of the BS 6 (BS) 6 .
The BS 6 exchanges messages with and transmits data to a Circuit Switched Core Network (CSCN) 7 and Packet Switched Core Network (PSCN) 8 . The CSCN 7 provides traditional voice communications and the PSCN 8 provides Internet applications and multimedia services.
The Mobile Switching Center (MSC) 5 portion of the CSCN 7 provides switching for traditional voice communications to and from a MS 2 and may store information to support these capabilities. The MSC 2 may be connected to one of more BS's 6 as well as other public networks, for example a Public Switched Telephone Network (PSTN) (not shown) or Integrated Services Digital Network (ISDN) (not shown). A Visitor Location Register (VLR) 9 is used to retrieve information for handling voice communications to or from a visiting subscriber. The VLR 9 may be within the MSC 5 and may serve more than one MSC.
A user identity is assigned to the Home Location Register (HLR) 10 of the CSCN 7 for record purposes such as subscriber information, for example Electronic Serial Number (ESN), Mobile Directory Number (MDR), Profile Information, Current Location, and Authentication Period. The Authentication Center (AC) 11 manages authentication information related to the MS 2 . The AC 11 may be within the HLR 10 and may serve more than one HLR. The interface between the MSC 5 and the HLR/AC 10 , 11 is an IS-41 standard interface 18 .
The Packet data Serving Node (PDSN) 12 portion of the PSCN 8 provides routing for packet data traffic to and from MS 2 . The PDSN 12 establishes, maintains, and terminates link layer sessions to the MS 2 's 2 and may interface with one of more BS 6 and one of more PSCN 8 .
The Authentication, Authorization and Accounting (AAA) 13 Server provides Internet Protocol authentication, authorization and accounting functions related to packet data traffic. The Home Agent (HA) 14 provides authentication of MS 2 IP registrations, redirects packet data to and from the Foreign Agent (FA) 15 component of the PDSN 8 , and receives provisioning information for users from the AAA 13 . The HA 14 may also establish, maintain, and terminate secure communications to the PDSN 12 and assign a dynamic IP address. The PDSN 12 communicates with the AAA 13 , HA 14 and the Internet 16 via an Internal IP Network.
There are several types of multiple access schemes, specifically Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA) and Code Division Multiple Access (CDMA). In FDMA, user communications are separated by frequency, for example, by using 30 KHz channels. In TDMA, user communications are separated by frequency and time, for example, by using 30 KHz channels with 6 timeslots. In CDMA, user communications are separated by digital code.
In CDMA, All users on the same spectrum, for example, 1.25 MHz. Each user has a unique digital code identifier and the digital codes separate users to prevent interference.
A CDMA signal uses many chips to convey a single bit of information. Each user has a unique chip pattern, which is essentially a code channel. In order to recover a bit, a large number of chips are integrated according to a user's known chip pattern. Other user's code patterns appear random and are integrated in a self-canceling manner and, therefore, do not disturb the bit decoding decisions made according to the user's proper code pattern.
Input data is combined with a fast spreading sequence and transmitted as a spread data stream. A receiver uses the same spreading sequence to extract the original data. FIG. 2A illustrates the spreading and de-spreading process. As illustrated in FIG. 2B , multiple spreading sequences may be combined to create unique, robust channels.
A Walsh code is one type of spreading sequence. Each Walsh code is 64 chips long and is precisely orthogonal to all other Walsh codes. The codes are simple to generate and small enough to be stored in read only memory (ROM).
A short PN code is another type of spreading sequence. A short PN code consists of two PN sequences (I and Q), each of which is 32,768 chips long and is generated in similar, but differently tapped 15-bit shift registers. The two sequences scramble the information on the I and Q phase channels.
A long PN code is another type of spreading sequence. A long PN code is generated in a 42-bit register and is more than 40 days long, or about 4×10 13 chips long. Due to its length, a long PN code cannot be stored in ROM in a terminal and, therefore, is generated chip-by-chip.
Each MS 2 codes its signal with the PN long code and a unique offset, or public long code mask, computed using the long PN code ESN of 32-bits and 10 bits set by the system. The public long code mask produces a unique shift. Private long code masks may be used to enhance privacy. When integrated over as short a period as 64 chips, MS 2 with different long PN code offsets will appear practically orthogonal.
CDMA communication uses forward channels and reverse channels. A forward channel is utilized for signals from a BTS 3 to a MS 2 and a reverse channel is utilized for signals from a MS to a BTS.
A forward channel uses its specific assigned Walsh code and a specific PN offset for a sector, with one user able to have multiple channel types at the same time. A forward channel is identified by its CDMA RF carrier frequency, the unique short code PN offset of the sector and the unique Walsh code of the user. CDMA forward channels include a pilot channel, sync channel, paging channels and traffic channels.
The pilot channel is a “structural beacon” which does not contain a character stream, but rather is a timing sequence used for system acquisition and as a measurement device during handoffs. A pilot channel uses Walsh code 0.
The sync channel carries a data stream of system identification and parameter information used by MS 2 during system acquisition. A sync channel uses Walsh code 32.
There may be from one to seven paging channels according to capacity requirements. Paging channels carry pages, system parameter information and call setup orders. Paging channels use Walsh codes 1-7.
The traffic channels are assigned to individual users to carry call traffic. Traffic channels use any remaining Walsh codes subject to overall capacity as limited by noise.
A reverse channel is utilized for signals from a MS 2 to a BTS 3 and uses a Walsh code and offset of the long PN sequence specific to the MS, with one user able to transmit multiple types of channels simultaneously. A reverse channel is identified by its CDMA RF carrier frequency and the unique long code PN Offset of the individual MS 2 . Reverse channels include traffic channels and access channels.
Individual users use traffic channels during actual calls to transmit traffic to the BTS 3 . A reverse traffic channel is basically a user-specific public or private long code Mask and there are as many reverse traffic channels as there are CDMA terminals.
An MS 2 not yet involved in a call uses access channels to transmit registration requests, call setup requests, page responses, order responses and other signaling information. An access channel is basically a public long code offset unique to a BTS 3 sector. Access channels are paired with paging channels, with each paging channel having up to 32 access channels.
CDMA communication provides many advantages. Some of the advantages are variable rate vocoding and multiplexing, power control, use of RAKE receivers and soft handoff.
CDMA allows the use of variable rate vocoders to compress speech, reduce bit rate and greatly increase capacity. Variable rate vocoding provides full bit rate during speech, low data rates during speech pauses, increased capacity and natural sound. Multiplexing allows voice, signaling and user secondary data to be mixed in CDMA frames.
By utilizing forward power control, the BTS 3 continually reduces the strength of each user's forward baseband chip stream. When a particular MS 2 experiences errors on the forward link, more energy is requested and a quick boost of energy is supplied after which the energy is again reduced.
Using a RAKE receiver allows a MS 2 to use the combined outputs of the three traffic correlators, or “RAKE fingers,” every frame. Each RAKE finger can independently recover a particular PN Offset and Walsh code. The fingers may be targeted on delayed multipath reflections of different BTS's 3 , with a searcher continuously checking pilot signals.
The MS 2 drives soft handoff. The MS 2 continuously checks available pilot signals and reports to the BTS 3 regarding the pilot signals it currently sees. The BTS 3 assigns up to a maximum of six sectors and the MS 2 assigns its fingers accordingly. Al messages are sent by dim-and-burst without muting. Each end of the communication link chooses the best configuration on a frame-by-frame basis, with handoff transparent to users.
A cdma2000 system is a third-generation (3G) wideband; spread spectrum radio interface system that uses the enhanced service potential of CDMA technology to facilitate data capabilities, such as Internet and intranet access, multimedia applications, high-speed business transactions, and telemetry. The focus of cdma2000, as is that of other third-generation systems, is on network economy and radio transmission design to overcome the limitations of a finite amount of radio spectrum availability.
FIG. 3 illustrates a data link protocol architecture layer 20 for a cdma2000 wireless network. The data link protocol architecture layer 20 includes an Upper Layer 60 , a Link Layer 30 and a Physical layer 21 .
The Upper layer 60 includes three sublayers; a Data Services sublayer 61 ; a Voice Services sublayer 62 and a Signaling Services sublayer 63 . Data services 61 are services that deliver any form of data on behalf of a mobile end user and include packet data applications such as IP service, circuit data applications such as asynchronous fax and B-ISDN emulation services, and SMS. Voice services 62 include PSTN access, mobile-to-mobile voice services, and Internet telephony. Signaling 63 controls all aspects of mobile operation.
The Signaling Services sublayer 63 processes all messages exchanged between the MS 2 and BS 6 . These messages control such functions as call setup and teardown, handoffs, feature activation, system configuration, registration and authentication.
The Link Layer 30 is subdivided into the Link Access Control (LAC) sublayer 32 and the Medium Access Control (MAC) sublayer 3 I. The Link Layer 30 provides protocol support and control mechanisms for data transport services and performs the functions necessary to map the data transport needs of the Upper layer 60 into specific capabilities and characteristics of the Physical Layer 21 . The Link Layer 30 may be viewed as an interface between the Upper Layer 60 and the Physical Layer 20 .
The separation of MAC 31 and LAC 32 sublayers is motivated by the need to support a wide range of Upper Layer 60 services and the requirement to provide for high efficiency and low latency data services over a wide performance range, specifically from 1.2 Kbps to greater than 2 Mbps. Other motivators are the need for supporting high Quality of Service (QoS) delivery of circuit and packet data services, such as limitations on acceptable delays and/or data BER (bit error rate), and the growing demand for advanced multimedia services each service having a different QoS requirements.
The LAC sublayer 32 is required to provide a reliable, in-sequence delivery transmission control function over a point-to-point radio transmission link 42 . The LAC sublayer 32 manages point-to point communication channels between upper layer 60 entities and provides framework to support a wide range of different end-to-end reliable Link Layer 30 protocols.
The Link Access Control (LAC) sublayer 32 provides correct delivery of signaling messages. Functions include assured delivery where acknowledgement is required, unassured delivery where no acknowledgement is required, duplicate message detection, address control to deliver a message to an individual MS 2 , segmentation of messages into suitable sized fragments for transfer over the physical medium, reassembly and validation of received messages and global challenge authentication.
The MAC sublayer 31 facilitates complex multimedia, multi-services capabilities of 3G wireless systems with QoS management capabilities for each active service. The MAC sublayer 31 provides procedures for controlling the access of packet data and circuit data services to the Physical Layer 21 , including the contention control between multiple services from a single user, as well as between competing users in the wireless system. The MAC sublayer 31 also performs mapping between logical channels and physical channels, multiplexes data from multiple sources onto single physical channels and provides for reasonably reliable transmission over the Radio Link Layer using a Radio Link Protocol (RLP) 33 for a best-effort level of reliability. Signaling Radio Burst Protocol (SRBP) 35 is an entity that provides connectionless protocol for signaling messages. Multiplexing and QoS Control 34 is responsible for enforcement of negotiated QoS levels by mediating conflicting requests from competing services and the appropriate prioritization of access requests.
The Physical Layer 20 is responsible for coding and modulation of data transmitted over the air. The Physical Layer 20 conditions digital data from the higher layers so that the data may be transmitted over a mobile radio channel reliably.
The Physical Layer 20 maps user data and signaling, which the MAC sublayer 31 delivers over multiple transport channels, into a physical channels and transmits the information over the radio interface. In the transmit direction, the functions performed by the Physical Layer 20 include channel coding, interleaving, scrambling, spreading and modulation. In the receive direction, the functions are reversed in order to recover the transmitted data at the receiver.
FIG. 4 illustrates an overview of call processing. Processing a call includes pilot and sync channel processing, paging channel processing, access channel processing and traffic channel processing.
Pilot and sync channel processing refers to the MS 2 processing the pilot and sync channels to acquire and synchronize with the CDMA system in the MS 2 Initialization State. Paging channel processing refers to the MS 2 monitoring the paging channel or the forward common control channel (F-CCCH) to receive overhead and mobile-directed messages from the BS 6 in the Idle State. Access channel processing refers to the MS 2 sending messages to the BS 6 on the access channel or the Enhanced access channel in the System Access State, with the BS 6 always listening to these channels and responding to the MS on either a paging channel or the F-CCCH. Traffic channel processing refers to the BS 6 and MS 2 communicating using dedicated forward and reverse traffic channels in the MS 2 Control on Traffic Channel State, with the dedicated forward and reverse traffic channels carrying user information, such as voice and data.
FIG. 5 illustrates the initialization state of a MS 2 . The Initialization state includes a System Determination Substate, Pilot Channel Acquisition, Sync Channel Acquisition, a Timing Change Substate and a Mobile Station Idle State.
System Determination is a process by which the MS 2 decides from which system to obtain service. The process could include decisions such as analog versus digital, cellular versus PCS, and A carrier versus B carrier. A custom selection process may control System Determination. A service provider using a redirection process may also control System determination. After the MS 2 selects a system, it must determine on which channel within that system to search for service. Generally the MS 2 uses a prioritized channel list to select the channel.
Pilot Channel Processing is a process whereby the MS 2 first gains information regarding system timing by searching for usable pilot signals. Pilot channels contain no information, but the MS 2 can align its own timing by correlating with the pilot channel. Once this correlation is completed, the MS 2 is synchronized with the sync channel and can read a sync channel message to further refine its timing. The MS 2 is permitted to search up to 15 seconds on a single pilot channel before it declares failure and returns to System Determination to select either another channel or another system. The searching procedure is not standardized, with the time to acquire the system depending on implementation.
In cdma2000, there may be many pilot channels, such as OTD pilot, STS pilot and Auxiliary pilot, on a single channel. During System Acquisition, the MS 2 will not find any of these pilot channels because they are use different Walsh codes and the MS is only searching for Walsh 0.
The sync channel message is continuously transmitted on the sync channel and provides the MS 2 with the information to refine timing and read a paging channel. The mobile receives information from the BS 6 in the sync channel message that allows it to determine whether or not it will be able to communicate with that BS.
In the Idle State, the MS 2 receives one of the paging channels and processes the messages on that channel. Overhead or configuration messages are compared to stored sequence numbers to ensure the MS 2 has the most current parameters. Messages to the MS 2 are checked to determine the intended subscriber.
The BS 6 may support multiple paging channels and/or multiple CDMA channels (frequencies). The MS 2 uses a hash function based on its IMSI to determine which channel and frequency to monitor in the Idle State. The BS 6 uses the same hash function to determine which channel and frequency to use when paging the MS 2 .
Using a Slot Cycle Index (SCI) on the paging channel and on F-CCCH supports slotted paging. The main purpose of slotted paging is to conserve battery power in MS 2 . Both the MS 2 and BS 6 agree in which slots the MS will be paged. The MS 2 can power down some of its processing circuitry during unassigned slots. Either the General Page message or the Universal Page message may be used to page the mobile on F-CCCH. A Quick paging channel that allows the MS 2 to power up for a shorter period of time than is possible using only slotted paging on F-PCH or F-CCCH is also supported.
FIG. 6 illustrates the System Access state. The first step in the system access process is to update overhead information to ensure that the MS 2 is using the correct access channel parameters, such as initial power level and power step increments. A MS 2 randomly selects an access channel and transmits without coordination with the BS 6 or other MS. Such a random access procedure can result in collisions. Several steps can be taken to reduce the likelihood of collision, such as use of a slotted structure, use of a multiple access channel, transmitting at random start times and employing congestion control, for example, overload classes.
The MS 2 may send either a request or a response message on the access channel. A request is a message sent autonomously, such as an Origination message. A response is a message sent in response to a message received from the BS 6 . For example, a Page Response message is a response to a General Page message or a Universal message.
The Multiplexing and QoS Control sublayer 34 has both a transmitting function and a receiving function. The transmitting function combines information from various sources, such as Data Services 61 , Signaling Services 63 or Voice Services 62 , and forms Physical layer SDUs and PDCHCF SDUs for transmission. The receiving function separates the information contained in Physical Layer 21 and PDCHCF SDUs and directs the information to the correct entity, such as Data Services 61 , Upper Layer Signaling 63 or Voice Services 62 .
The Multiplexing and QoS Control sublayer 34 operates in time synchronization with the Physical Layer 21 . If the Physical Layer 21 is transmitting with a non-zero frame offset, the Multiplexing and QoS Control sublayer 34 delivers Physical Layer SDUs for transmission by the Physical Layer at the appropriate frame offset from system time.
The Multiplexing and QoS Control sublayer 34 delivers a Physical Layer 21 SDU to the Physical Layer using a physical-channel specific service interface set of primitives. The Physical Layer 21 delivers a Physical Layer SDU to the Multiplexing and QoS Control sublayer 34 using a physical channel specific Receive Indication service interface operation.
The SRBP Sublayer 35 includes the sync channel, forward common control channel, broadcast control channel, paging channel and access channel procedures.
The LAC Sublayer 32 provides services to Layer 3 60 . SDUs are passed between Layer 3 60 and the LAC Sublayer 32 . The LAC Sublayer 32 provides the proper encapsulation of the SDUs into LAC PDUs, which are subject to segmentation and reassembly and are transferred as encapsulated PDU fragments to the MAC Sublayer 31 .
Processing within the LAC Sublayer 32 is done sequentially, with processing entities passing the partially formed LAC PDU to each other in a well-established order. SDUs and PDUs are processed and transferred along functional paths, without the need for the upper layers to be aware of the radio characteristics of the physical channels. However, the upper layers could be aware of the characteristics of the physical channels and may direct Layer 2 30 to use certain physical channels for the transmission of certain PDUs.
A 1xEV-DO system is optimized for packet data service and characterized by a single 1.25 MHz carrier (“1x”) for data only or data Optimized (“DO”). Furthermore, there is a peak data rate of 2.4 Mbps or 3.072 Mbps on the forward Link and 153.6 Kbps or 1.8432 Mbps on the reverse Link. Moreover, a 1xEV-DO system provides separated frequency bands and internetworking with a 1x System. Figure illustrates a comparison of cdma2000 for a 1x system and a 1xEV-DO system.
In CDMA2000, there are concurrent services, whereby voice and data are transmitted together at a maximum data rate of 614.4 kbps and 307.2 kbps in practice. An MS 2 communicates with the MSC 5 for voice calls and with the PDSN 12 for data calls. A cdma2000 system is characterized by a fixed rate with variable power with a Walsh-code separated forward traffic channel.
In a 1xEV-DO system, the maximum data rate is 2.4 Mbps or 3.072 Mbps and there is no communication with the circuit-switched core network 7 . A 1xEV-DO system is characterized by fixed power and a variable rate with a single forward channel that is time division multiplexed.
FIG. 8 illustrates a 1xEV-DO system architecture. In a 1xEV-DO system, a frame consists of 16 slots, with 600 slots/see, and has a duration of 26.67 ms, or 32,768 chips. A single slot is 1.6667 ms long and has 2048 chips. A control/traffic channel has 1600 chips in a slot a pilot channel has 192 chips in a slot and a MAC channel has 256 chips in a slot. A 1xEV-DO system facilitates simpler and faster channel estimation and time synchronization.
FIG. 9 illustrates a 1xEV-DO default protocol architecture. FIG. 10 illustrates a 1xEV-DO non-default protocol architecture.
Information related to a session in a 1xEV-DO system includes a set of protocols used by an MS 2 , or access terminal (AT), and a BS 6 , or access network (AN), over an airlink, a Unicast Access Terminal Identifier (UATI), configuration of the protocols used by the AT and AN over the airlink and an estimate of the current AT location.
The Application Layer provides best effort, whereby the message is sent once, and reliable delivery, whereby the message can be retransmitted one or more times. The stream layer provides the ability to multiplex up to 4 (default) or 255 (non-default) application streams for one AT 2 .
The Session Layer ensures the session is still valid and manages closing of session, specifies procedures for the initial UATI assignment, maintains AT addresses and negotiates/provisions the protocols used during the session and the configuration parameters for these protocols.
FIG. 11 illustrates the establishment of a 1xEV-DO session. As illustrated in FIG. 14 , establishing a session includes address configuration, connection establishment, session configuration and exchange keys.
Address configuration refers to an Address Management protocol assigning a UATI and Subnet mask. Connection establishment refers to Connection Layer Protocols setting up a radio link. Session configuration refers to a Session Configuration Protocol configuring all protocols. Exchange key refers a Key Exchange protocol in the Security Layer setting up keys for authentication.
A “session’ refers to the logical communication link between the AT 2 and the RNC, which remains open for hours, with a default of 54 hours. A session lasts until the PPP session is active as well. Session information is controlled and maintained by the RNC in the AN 6 .
When a connection is opened, the AT 2 can be assigned the forward traffic channel and is assigned a reverse traffic channel and reverse power control channel. Multiple connections may occur during single session.
The Connection Layer manages initial acquisition of the network and communications. Furthermore, the Connection Layer maintains an approximate AT 2 location and manages a radio link between the AT 2 and the AN 6 . Moreover, the Connection Layer performs supervision, prioritizes and encapsulates transmitted data received from the Session Layer, forwards the prioritized data to the Security Layer and decapsulates data received from the Security Layer and forwards it to the Session Layer.
FIG. 12 illustrates Connection Layer Protocols. As illustrated in FIG. 12 , the protocols include an Initialization State, an Idle State and a Connected State.
In the Initialization State, the AT 2 acquires the AN 6 and activates the initialization State Protocol. In the Idle State, a closed connection is initiated and the Idle State Protocol is activated. In the Connected State, an open connection is initiated and the Connected State Protocol is activated.
A closed connection refers to a state where the AT 2 is not assigned any dedicated air-link resources and communications between the AT and AN 6 are conducted over the access channel and the control channel. An open connection refers to a state where the AT 2 can be assigned the forward traffic channel, is assigned a reverse power control channel and a reverse traffic channel and communication between the AT 2 and AN 6 is conducted over these assigned channels as well as over the control channel.
The Initialization State Protocol performs actions associated with acquiring an AN 6 . The Idle State Protocol performs actions associated with an AT 2 that has acquired an AN 6 , but does not have an open connection, such as keeping track of the AT location using a Route Update Protocol. The Connected State Protocol performs actions associated with an AT 2 that has an open connection, such as managing the radio link between the AT and AN 6 and managing the procedures leading to a closed connection. The Route Update Protocol performs actions associated with keeping track of the AT 2 location and maintaining the radio link between the AT and AN 6 . The Overhead Message Protocol broadcasts essential parameters, such as QuickConfig, SectorParameters and AccessParameters message, over the control channel. The Packet Consolidation Protocol consolidates and prioritizes packets for transmission as a function of their assigned priority and the target channel as well as providing packet de-multiplexing on the receiver.
The Security Layer includes a key exchange function, authentication function and encryption function. The key exchange function provides the procedures followed by the AN 2 and AT 6 for authenticating traffic. The authentication function provides the procedures followed by the AN 2 and AT 6 to exchange security keys for authentication and encryption. The encryption function provides the procedures followed by the AN 2 and AT 6 for encrypting traffic.
The 1xEV-DO forward Link is characterized in that no power control and no soft handoff is supported. The AN 6 transmits at constant power and the AT 2 requests variable rates on the forward Link. Because different users may transmit at different times in TDM, it is difficult to implement diversity transmission from different BS's 6 that are intended for a single user.
In the MAC Layer, two types of messages originated from higher layers are transported across the physical layer, specifically a User data message and a signaling message. Two protocols are used to process the two types of messages, specifically a forward traffic channel MAC Protocol for the User data message and a control channel MAC Protocol, for the signaling message.
The Physical Layer is characterized by a spreading rate of 1.2288 Mcps, a frame consisting of 16 slots and 26.67 ms, with a slot of 1.67 ms and 2048 chips. The forward Link channel includes a pilot channel, a forward traffic channel or control channel and a MAC channel.
The pilot channel is similar to the to the cdma2000 pilot channel in that it comprises all “0” information bits and Walsh-spreading with W0 with 192 chips for a slot.
The forward traffic channel is characterized by a data rate that varies from 38.4 kbps to 2.4576 Mbps or from 4.8 kbps to 3.072 Mbps. Physical Layer packets can be transmitted in 1 to 16 slots and the transmit slots use 4-slot interlacing when more than one slot is allocated. If ACK is received on the reverse Link ACK channel before all of the allocated slots have been transmitted, the remaining slots shall not be transmitted.
The control channel is similar to the sync channel and paging channel in cdma2000. The control channel is characterized by a period of 256 slots or 427.52 ms, a Physical Layer packet length of 1024 bits or 128, 256, 512 and 1024 bits and a data rate of 38.4 kbps or 76.8 kbps or 19.2 kbps, 38.4 kbps or 76.8 kbps.
The 1xEV-DO reverse link is characterized in that the AN 6 can power control the reverse Link by using reverse power control and more than one AN can receive the AT's 2 transmission via soft handoff. Furthermore, there is no TDM on the reverse Link, which is channelized by Walsh code using a long PN code.
An access channel is used by the AT 2 to initiate communication with the AN 6 or to respond to an AT directed message. Access channels include a pilot channel and a data channel.
An AT 2 sends a series of access probes on the access channel until a response is received from the AN 6 or a timer expires. An access probe includes a preamble and one or more access channel Physical Layer packets. The basic data rate of the access channel is 9.6 kbps, with higher data rates of 19.2 kbps and 38.4 kbps available.
When more that one AT 2 is paged using the same Control channel packet, Access Probes may be transmitted at the same time and packet collisions are possible. The problem can be more serious when the ATs 2 are co-located, are in a group call or have similar propagation delays.
Multiple input, multiple output (MIMO) refers to the use of multiple antennas at the transmitter and the receiver for improved performance. When two transmitters and two or more receivers are used, for example, two simultaneous data streams can be sent, which double the data rate.
In MIMO, two operations mode can be assumed based on the availability of channel status information at the transmitter side—open-loop and closed-loop operations. In the open-loop operation, channel information is not assumed. Albeit simplicity of the operation, due to lack of channel status information, open-loop operation can incur performance loss.
Different from the open-loop operation, in the closed-loop operation, partial or full channel status information can be assumed.
The operations of MIMO transmission often require overhead transmission from all antennas involved. As a result, resources (e.g., power) can be wasted and throughput can be affected due to interference(s) intended for other users.
In order to promote improved performance in both the open-loop and the closed-loop operations in the MIMO systems, transmission of overhead can be modified. In other words, transmission of overhead (e.g., preamble, a medium access control (MAC), and/or pilot in 1xEV-DO) can be reduced. Consequently, transmission power can be used more effectively and efficiently as well as interference leading to throughput increase can be reduced.
FIG. 13 illustrates an exemplary diagram of a multiple antenna transmission architecture. More specifically, FIG. 13 is an architecture for transmit diversity with antenna selection. Referring to FIG. 13 , data stream is encoded based on feedback information provided from the receiving side. More specifically, based on the feedback information, the data is processed using an adaptive modulation and coding (AMC) scheme at the transmitting end. The data processed according to the AMC scheme is channel coded, interleaved, and then modulated into symbols (which can also be referred to as coded or modulated data stream).
The symbols are then demultiplexed to multiple STC encoder blocks. Here, demultiplexing is based on the code rate and modulation that the carrier can support. Each STC encoder block encodes the symbols and outputs to encoded symbols to inverse fast Fourier transform (IFFT) block(s). The IFFT block transforms the encoded symbols. The transformed symbols are then assigned to antennas selected by antenna selector(s) for transmission to the receiving end. The selection as to which antenna to be used for transmission can be based on the feedback information.
FIG. 14 is another exemplary diagram illustrating transmit diversity combined with antenna selection. Different from FIG. 13 which is designed for a single codeword (SWC) operation, in FIG. 14 , adaptive modulation and coding is performed per carrier basis and is designed for a multiple codeword (MWC) operation.
According to FIGS. 13 and 14 , the data is processed by the STC encoders before being processed by the IFFT block(s). However, it is possible for the data to be processed by the IFFT block before being processed by the STC encoder blocks. In short, the processing order between the STC encoders and the IFFT blocks can be switched.
In detail, the feedback information from the receiving end can be used in performing channel coding and modulation (or in executing the AMC scheme) to the data stream. This AMC scheme process is illustrated in a dotted box. The feedback information used in channel coding and modulation can be a data rate control (DRC) or a channel quality indicator (CQI), for example. Further, the feedback information can include various information such as sector identification, carrier/frequency index, antenna index, supportable CQI value, best antenna combination, selected antennas, and a supportable signal-to-interference noise ratio (SINR) for a given assigned multi-carriers.
The information related to selected antennas as well as its supportable SINR can be transmitted through a channel from the receiving end to the transmitting end (e.g., reverse link) or on a different channel. Such a channel can be a physical channel or a logical channel. Further, the information related to the selected antennas can be transmitted in a form of a bitmap. The position of each bitmap represents the antenna index.
The DRC or the CQI, for example, can be measured per transmit antenna. As an example of the CQI, a transmitting end can send signal (e.g., pilot) to a receiving end to determine the quality of the channel(s) through which the signal was sent. Each antenna transmits its own pilot for the receiving end to extract the channel information from the antenna element to the receiving end. The transmitting end can also be referred to as an access node, base station, network, or Node B. Moreover, the receiving end can also be referred to as an access terminal, mobile terminal, mobile station, or mobile terminal station. In response to the signal from the transmitting end, the receiving end can send to the transmitting end the CQI to provide the channel status or channel condition of the channel through which the signal was sent.
Furthermore, the feedback information (e.g., DRC or CQI) can be measured using a pre-detection scheme or a post-detection scheme. The pre-detection scheme includes inserting antenna-specific known pilot sequence before an orthogonal frequency division multiplexing (OFDM) block using a time division multiplexing (TDM). The post-detection scheme involves using antenna-specific known pilot pattern in OFDM transmission.
Further, the feedback information is based on each bandwidth or put differently, the feedback information includes the channel status information on each of N number of 1.25 MHz, 5 MHz, or a sub-band of OFDM bandwidth.
As discussed, the symbols processed using the AMC scheme are demultiplexed to multiple STC encoder blocks. The STC encoder blocks can implement various types of coding techniques. For example, the encoder block can be a STC encoder. Each STC encoder can have a basic unit of MHz. In fact, in FIG. 16 , the STC encoder covers 1.25 MHz. Other types of coding techniques include space-time block code (STBC), non-orthogonal STBC (NO-STBC), space-time Trellis coding (STTC), space-frequency block code (SFBC), space-time frequency block code (STFBC), cyclic shift diversity, cyclic delay diversity (CDD), Alamouti, and precoding.
As discussed, the IFFT transformed symbols are assigned to specific antenna(s) by the antenna selectors based on the feedback information. That is, in FIG. 16 , the antenna selector chooses the pair of antenna corresponding to two outputs from the STC encoder specified in the feedback information.
The antenna selectors select the antennas for transmitting specific symbols. At the same time, the antenna selector can choose the carrier (or frequency bandwidth) through which the symbols are transmitted. The antenna selection as well as frequency selection is based on the feedback information which is provided per each bandwidth of operation. Furthermore, the wireless system in which antenna and frequency allocation is made can be a multi input, multi output (MIMO) system.
In the MIMO system having multiple antennas, the antennas for transmitting data can be classified as primary antenna(s) and secondary antenna(s). The primary antenna(s) can be defined by the antenna(s) that provides best reception quality or the antenna(s) with the smallest index among the antennas involved in the transmission.
FIG. 15 is an exemplary diagram illustrating overhead reduction transmission. Here, a single antenna (also referred to as a primary antenna) is used to carry the overhead information. As discussed, the primary antenna can be selected based on criteria. That is, the antenna having the best channel condition or the antenna having the smallest index can be selected as the primary antenna.
The primary antenna can be used to carry (or transmit) the preamble. The preamble can include information on the data packet. Moreover, the primary antenna can be used to carry the overhead information which can include pilot and medium access control (MAC). In addition, the primary antenna can be used to transmit data including the code division multiplex (CDM) data and the OFDM data. Furthermore, any retransmission of the preambles is transmitted via the primary antenna.
The antenna not selected as the primary antenna or having less-than-best channel condition and/or not the smallest index can be selected as secondary antenna. The secondary antenna can be used to transmit only the data (e.g., CDM data and OFDM data). Unlike the primary antenna, the secondary antenna does not transmit the preambles nor the overhead information. The overhead information is transmitted via the primary antenna so as to support legacy access terminals (ATs) and/or new ATs. Here, support of the legacy AT can be referred to as transmission of CDM data, and the new AT can be referred to as transmission of the OFDM data.
The transmission of the preambles (e.g., legacy preamble) and the legacy data (e.g., CDM data) usually take place in a sub-slot (or a quarter slot). The sub-slot usually has a duration of 400 chips, and often, a portion of the 400 chips are occupied by the preamble while the remaining portion of the 400 chips are occupied by the data.
Referring to FIG. 15 , Antenna ‘ 0 ’ and Antenna ‘ 2 ’ are selected for transmitting data on carriers 0 and 1 . Moreover, Antenna ‘ 0 ’ and Antenna ‘ 1 ’ are selected for transmitting data on carrier 2 , and Antenna ‘ 1 ’ and Antenna ‘ 2 ’ are selected for transmitting data on carrier 3 . Hence, Antenna ‘ 0 ’ is the primary antenna for carriers 0 , 1 , and 2 , and Antenna ‘ 1 ’ is the primary antenna for carrier 3 .
As discussed, the selection of the primary antenna can be based on the reception quality. That is, the primary antenna can be defined as the antenna that provides the best reception quality. Alternatively, the selection of the primary antenna can be based on the smallest index among the antennas involved in the transmission such as in the case of more than one antenna selection-based transmission, spatial multiplexing, and transmit diversity-based transmission.
Preamble can be transmitted over carriers via one antenna or multiple antennas. More specifically, in FIG. 15 , the preamble is transmitted using the first portion of the basic transmission unit. For example, in 1xEV-DO, basic unit is slot with duration of 1.667 ms and the first portion is ¼ slot with the duration of 400 chips (duration of each chip is 1/1.2288 μs). Preamble transmission takes place using the portion of ¼ slot.
In FIG. 15 , the preambles from Blocks # 0 , # 1 , and # 2 are transmitted on carriers 0 , 1 , and 2 (also indicated as f 0 , f 1 , and f 2 ). Moreover, the preamble from Block # 3 is transmitted on carrier 3 (also indicated as f 3 ). Since Antenna ‘ 0 ’ is the primary antenna for carriers 0 , 1 , and 2 , and Antenna ‘ 1 ’ is the primary antenna for carrier 3 , the preambles are transmitted accordingly using the first portion of respective slots. Furthermore, retransmissions of the preambles are made via the primary antenna(s) only.
Further to transmission in ¼ slot (or sub-slot) of the preamble and the CDM data, the preamble can also be transmitted with an orthogonal frequency division multiplexing (OFDM) data. As discussed, FIG. 15 shows the example transmission assuming preamble+CDM data transmission in ¼ slot.
According to the embodiment of FIG. 15 , transmission(s) and/or retransmission(s) of overhead information are transmitted using only the primary antenna. The overhead can include a preamble for user identification or channel type (e.g., data or control channel), medium access control (MAC), and pilot as in 1xEV-DO. In addition, the overhead including pilot and medium access control (MAC) can be made through the primary antenna so as to support legacy access terminals (ATs) and/or new ATs.
Data can be transmitted through both the primary and second antennas, as illustrated in FIG. 16 . Here, the data transmission antenna-specific pilot signals can be transmitted to help new ATs estimate the channel from each antenna.
FIG. 16 is an exemplary diagram illustrating transmission assuming preamble and OFDM data transmission. More specifically, FIG. 16 illustrates transmission of preamble and OFDM data in the ¼ transmission slot.
As discussed, the primary antenna and the secondary antenna can be selected based on channel condition and/or size of the index. It is possible in multiple antenna situations to have more than one secondary antenna.
Referring to FIG. 16 , transmission of the overhead, including pilot and MAC, is made by Antenna ‘ 0 ’ for backward compatibility support. If, however, backward compatibility can be ignored or is no longer an issue, then only the preamble can be fixed and/or sent by a fixed antenna (e.g., Antenna ‘ 0 ’). Even if backward compatibility is no longer an issue, the preamble can be sent by each carrier having the best channel condition. However, there can be signaling problem based on condition, and therefore, it is better to fix or select the antenna for transmission for improved reliability.
The preamble is assumed to be transmitted using some assigned sub-carrier(s). In FIG. 16 , both primary and secondary antennas can be used to transmit the preambles, but the MAC and pilot are transmitted using only primary antenna.
As discussed, the preambles can be sent by only one antenna. For example, the primary antenna (e.g., Antenna ‘ 0 ’) can be used to transmit the preambles. In other words, Antenna ‘ 0 ’ can be selected for transmitting data on carriers 0 , 1 , 2 , and 3 . Hence, Antenna ‘ 0 ’ is considered the primary antenna.
Further, the preambles can be sent by multiple antennas. For example, FIG. 16 illustrates the preamble being transmitted by all three antennas. That is, the preambles are transmitted via not only the primary antennas but also secondary antennas.
For carrier 0 , antennas 0 and 2 are selected. As such, Antenna ‘ 0 ’ is the primary antenna and Antenna ‘ 2 ’ is the secondary antenna.
Different from a situation where the preambles are transmitted from/by only one antenna, the preambles are transmitted and retransmitted only through the primary antenna. In a situation where the preambles are transmitted from/by multiple antennas, the preambles are not limited to transmission from only the primary antenna but the secondary antenna can be also used.
In short, the preambles of FIG. 16 are transmitted via the primary antennas (e.g., Antenna ‘ 0 ’ and Antenna ‘ 1 ’), and any retransmissions of the preambles can only take place via the primary antennas. However, if the preambles are sent by multiple antennas, as illustrated in FIG. 16 , both the primary and secondary antennas can be used to transmit the preambles.
FIG. 17 is another exemplary diagram illustrating transmission of preamble and OFDM data. Here, the basic bandwidth is assigned as a whole. That is, different from FIG. 15 , multiple of the basic unit of bandwidth (i.e., 1.25 MHz) is assigned as a whole. In other words, the gap(s) between the carriers (or bands) can be eliminated and used as a part of the OFDM data. Moreover, the overhead transmission (e.g., pilot and MAC) can be combined to eliminate the gap(s) between carriers as well.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventions. Thus, it is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
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A method of transmitting data in a multi input, multi output (MIMO) system is disclosed. More specifically, the method includes selecting a primary antenna, based on satisfying at least one specified criteria, for transmitting a preamble, and transmitting the preamble via the primary antenna.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This Application is a U.S. National filing under §371 of International Application No. PCT/GB2005/001883, with an international filing date of 17 May 2005, now pending, claiming priority from Great Britain Application No. GB2004/10993.0, with a filing date of 17 May 2004, now pending, and herein incorporated by reference.
TECHNICAL FIELD
The invention relates to a feeding bottle for example a vented feeding bottle.
BACKGROUND OF THE INVENTION
Conventional feeding bottles comprise a container and a teat held on the container by a screw-on collar. A problem with conventional feeding bottles is that as an infant sucks on the teat a negative pressure builds up within the container as a result of which it becomes progressively more difficult to feed which can give rise to problems such as colic.
Various solutions have been proposed for alleviating the problem for example providing valves allowing air ingress. One example of such a solution is described in European patent application EP0845971. According to this document a feeding bottle includes a reservoir tube communicating at its upper end with a vent to atmosphere. The reservoir tube has a bulbous upper reservoir portion with an air tube projecting down into it from the air vent. An air conduit portion projects down from the reservoir portion to a point close to the bottom of the container. In the upright position the container is filled with liquid nearly to the height of the reservoir portion. When the container is inverted the end of the air conduit portion projects above the level of the liquid and the liquid previously in the air conduit portion drains into the reservoir portion and sits below the end of the air tube. As a result an air passage is provided from the vent via the air tube into the reservoir portion and through the air conduit to the bottle such that pressure equalisation is provided when the infant drinks. However, there are various disadvantages to this arrangement. Firstly a very complex arrangement is required. Furthermore because no valves are provided, if the infant distorts the teat while feeding for example by biting down on it there is less resistance and liquid is pushed away from the teat.
Another approach is described in U.S. Pat. No. 6,499,615 which describes a bottle having an angled neck and a valved vent tube. Once again complex and specialised components are required for this arrangement which also presents cleaning difficulties and even choking hazards as a result of the numerous small parts involved.
Furthermore, in known valved, vented feeding bottles, during the bottle feeding process the pressures fluctuate between positive and negative throughout the feed. When the infant bites down on or compresses the teat during feeding this action creates positive pressure in the bottle as the milk is pushed back into the bottle, acting on the valve to close it and directing milk flow out of the teat. As the infant creates suction to draw more milk from the bottle a negative pressure is induced in the bottle as milk is dispensed and when this occurs the valve at the end of the tube opens allowing air into the bottle. However in known systems a relatively significant negative pressure is required before the valve opens to allow air to vent such that the infant must suck unnaturally hard before pressure equalisation takes place. Accordingly known systems do not closely mimic natural feeding.
SUMMARY OF THE INVENTION
The invention is set out in the claims. Because the pressure at which the valve opens is minimised, the valve can vent at the very low negative pressures associated with infant feeding as a result of which the bottle provides a close similarity to natural breast feeding.
Furthermore, because of the provision of an anti-choke portion, feeding hazards are reduced and it is found also that the anti-choke portion provides a useful stirring/mixing member. Furthermore, by providing a feeding bottle insert with a sealing portion which itself provides a liquid passage as well as an air vent passage a simple modular constructions is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments of the invention will now be described by way of example, with reference to the figures of which:
FIG. 1 is a sectional side view of a feeding bottle according to a first embodiment of the present invention;
FIG. 2 is a sectional view of a detail of the feeding bottle insert shown in FIG. 1 ;
FIG. 3 a is a sectional perspective view of a valve and valve flange assembly according to an embodiment of the present invention;
FIG. 3 b is a top plan view of the valve and valve flange assembly of FIG. 3 a;
FIG. 3 c is a front view of the valve and valve flange assembly of FIG. 3 a;
FIG. 3 d is a side view of the valve and valve flange assembly of FIG. 3 a;
FIG. 3 e is a bottom plan view of the valve and valve flange assembly of FIG. 3 a;
FIG. 4 a is a perspective view of an alternative valve and valve flange assembly according to and embodiment of the present invention;
FIG. 4 b is a bottom plan view of the valve and valve flange assembly of FIG. 4 a;
FIG. 4 c is a side view of the valve and valve flange assembly of FIG. 4 a;
FIG. 5 a is a sectional side view of a feeding bottle according to a second embodiment of the present invention;
FIG. 5 b is plan view of the teat according to the second embodiment of the present invention;
FIG. 6 a is a sectional side view of a detail of the feeding bottle according to a third embodiment of the present invention;
FIG. 6 b is plan view of the teat according to the third embodiment of the present invention;
FIG. 7 a is a plan view of an alternative feeding bottle head portion;
FIG. 7 b is a sectional view along the line A-A of the feeding bottle head portion of FIG. 7 a;
FIG. 7 c is a sectional view along the line B-B of the feeding bottle head portion of FIG. 7 a and
FIG. 7 d is a perspective view of the feeding bottle head portion of FIG. 7 a.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1 , a feeding bottle designated generally 10 includes a teat 12 mounted by a screw collar 14 onto a container 16 . As is conventional, the collar 14 includes a central orifice through which the teat protrudes and the teat includes a flange of similar diameter to the container such that when the collar is screwed down a seal is formed by pressure of the collar on the flange of the teat.
The feeding bottle 10 further includes a vent assembly in the form of a neck insert 18 including a head portion 20 and a vent tube 22 projecting downwardly from the head portion. The head portion 20 includes a liquid conduit 24 providing communication between the container 16 and the teat 12 such that when the feeding bottle is inverted liquid passes via the liquid conduit 24 from the container into the teat allowing the infant to feed. Isolated from the liquid conduit 24 the head portion also includes an air passage 26 communicating with the vent tube 22 at one end and with atmosphere at the other end.
The head portion 20 includes an upper flange portion 28 of similar diameter to the container and arranged to fit on the lip of the container to be gripped in a liquid tight condition by the flange of the teat 12 pressed down by the collar 14 as described above. The flange portion 28 is of sufficient thickness to allow a generally radially extending bore to be formed inwardly from the cylindrical side wall providing the air passage 26 . The air passage opens to atmosphere via the screw threads of the collar 14 and is sealed against liquid passage by virtue of the seal formed by the neck insert flange portion 28 against the lip of the container 16 .
The air passage 26 communicates at its other end with a formation 30 provided on the lower face of the head portion 20 comprising an open-ended chamber on to which the vent tube 22 is an airtight push fit. The vent tube 22 extends downwardly nearly to the bottom of the container and includes at its lower end 32 a one-way valve 34 . In the embodiment shown the valve 34 comprises a duck-billed valve of well-known type which allows passage of air in one direction, into the container, but prevents the flow of liquid in the opposite direction, into the vent tube 22 . Also provided at the lower end 32 of the vent tube 22 is a valve flange 36 which in the embodiment shown is in fact formed integrally with the valve 34 and both of which are a push fit or otherwise airtight connection to the vent tube 22 . The valve flange 36 can form, for example, a ring around and concentric with the vent tube 22 and joined thereto by a web or ribs. The valve flange allows improved mixing and prevents a choking hazard in the event that the valve 34 should become detached for any reason.
In use the neck insert 18 is assembled (or pre-assembled) by fitting the valve 34 and flange 36 on to the vent tube 22 and fitting the vent tube 22 at its other end to the corresponding formation 30 of the head portion 20 . The container 16 is filled and the neck insert 18 is placed on the upper lip of the container 16 . The teat 12 is then placed on top of the neck insert 18 and the assembly is liquid sealed by screwing the collar 14 down as discussed in more detail above. When mixing is required this can be facilitated by virtue of the valve flange 36 . When the container is inverted liquid passes from the container 16 through the liquid conduit 24 in the neck insert 18 into the teat 12 . When the infant sucks or feeds on the teat 12 , causing a pressure drop in the container 16 , air enters the container via the air passage 26 , the vent tube 22 and the valve 34 such that pressure is equalised and a vacuum build-up is greatly reduced.
Referring to FIG. 2 the head portion 20 of the neck insert 18 is shown in more detail. As can be seen the head portion includes a flange portion 28 that is generally disc shaped and provides a seal around the neck of the container 16 (not shown) and a liquid conduit 24 in the direction perpendicular to the plane of the flange. The air passage 26 passes through the cylindrical wall of the flange portion 28 generally to the centre of the flange portion 28 providing a passage to the formation 30 and vent tube 22 (not shown).
Referring to FIGS. 3 a to 3 e the valve 34 and valve flange 36 are shown in more detail and in particular it will be seen that a ring-shaped or other profile of valve flange 36 can be provided and mounted in any appropriate manner for example by virtue of spokes extending from the central hub 35 on which the valve 34 is mounted or by an apertured web 37 as shown.
FIGS. 4 a , 4 b and 4 c show an alternative one way vent valve that can be implemented in the embodiments of present invention. The hemispherical valve 40 comprises a hemispherical shaped membrane with a central slit 41 which allows the passage of air therethrough. Any suitable cut such as a cross is also possible. The slit or cut is dimensioned to allow low pressure air venting as well as high temperature sealing.
The hemispherical valve of FIGS. 4 a to 4 c could also be used for other applications. For example, it could be located on the apex of the teat to allow the passage of fluid therethrough or on the flange of the teat to allow passage of air therethrough.
The dimension, material and construction of the valve 34 or 40 is of particular significance in obtaining a natural feeding action for the bottle. Most valving systems currently known allow a teat to vent at approximately 50 mB (milliBar) by virtue of the closing force determined by the resilience of the valve walls surrounding the slit, for example because of their stiffness. As a result, in use, the infant must exert an unnaturally high sucking force before venting can take place which can give rise to problems and results in sucking action more powerful than that required in natural feeding. However in known systems such a high resilient closing force is required to ensure that the valve does not leak milk into the vent tube, for example when the infant exerts squeezing pressure on the teat.
The valve 34 or 40 according to the present invention, on the other hand, is constructed such that a negative pressure in the region of 1 to 25 mB, more preferably 5 to 15 mB and most preferably 10 mB will be sufficient to open the valve to allow venting when the infant sucks on the bottle, requiring significantly less suction by the infant and a more natural feeding action. In particular this is allowed because of the recognition, according to the invention, that it is only necessary to prevent leakage of milk into the valve and vent tube when the bottle is in the upright position (and hence the valve is immersed in milk) whereas when the infant is sucking on the teat the bottle will tend to be inverted such that the valve is positioned above the level of the milk. Even if the valve opens when it is immersed in milk, no liquid will enter the valve and vent tube
Accordingly the invention recognises that a less significant resilient closing force is required for the valve because of the additional force applied to the sides of the valve when the bottle is standing upright as a result of the head of pressure exerted by the milk in the bottle. This force provides the additional closing force sufficient to prevent leakage into the valve and vent tube. Accordingly when the infant is drinking from the bottle in its inverted position, because the valve has a smaller resilient closing force it opens under a lower negative pressure as a result of which a more natural feeding action is represented.
It will be appreciated that the skilled reader can fabricate an appropriate duck-billed valve or hemispherical valve to meet the criteria set out above using routine trial and experimentation, for example by varying the wall or membrane thickness and hence stiffness of valves and applying an appropriate negative pressure to obtain venting at the desired pressure and/or by immersing the valves in liquids of a similar density to that of milk or other fluids used by the infant with an appropriate head of pressure, for example 5 to 10 cm. Preferably the valve is fabricated so that it remains closed even with a low head of pressure, for example 5 mm.
In the specific embodiment shown with respect to FIGS. 3 a to 3 e , the valve is formed of pure silicone rubber with typical 30 to 60 Shore A hardness as available from any silicone supplier such as GE, Bayer, Dow, Wacker, Rhone Poulenc. Both liquid silicone and compression moulding silicone grades are suitable for the present invention as they provide high heat stability, important for repeated heat sterilising methods. Other grades may also be suitable. The valve walls having a valve thickness 0.5 mm. Viewed from the front the duck-billed valve forms the shape of an inverted triangle of height 10.0 mm and base 8.0 mm. Viewed from the side the duck-billed valve is generally rectangular in cross-section having a width of 7.0 mm. A slit is formed on the exit end of the valve by a cut with a length of 2.5 mm to 4 mm. It is found that this configuration provides the desired operating range and in particular an ability to open up under a negative pressure of just 10 mB.
In the specific embodiment shown with respect to FIGS. 4 a to 4 c , the hemispherical valve is formed of pure silicone rubber with typical 30 to 60 Shore A hardness as available from any silicone supplier such as GE, Bayer, Dow, Wacker, Rhone Poulenc. Both liquid silicone and compression moulding silicone grades are suitable for the present invention as they provide high heat stability, important for repeated heat sterilising methods. Other grades may also be suitable. The key dimensions of the hemispherical valve 40 for high temperature sealing are its radius, wall thickness, length of central slit 41 and material softness. The hemispherical valve has a radius of 2 mm to 5 mm, most preferably 3.5 mm, and a wall thickness of 0.3 mm to 0.7 mm, most preferably 0.5 mm. The central slit dimension is in the region of 2.5 mm to 4.0 mm. It is found that this configuration provides low level suction but is also inherently strong enough to withstand pressures associated with liquid up to boiling point temperature without leakage.
FIGS. 5 a and 5 b show a second embodiment of the present invention in which there is an alternative air entry system. An air passage is formed by an air inlet aperture 51 on the flange of the teat 12 and an air conduit member 50 projecting downwardly of the teat. The air conduit member 50 provides communication between atmosphere and a vent tube 22 which is attached to the air conduit member with an airtight push fit. The air conduit member 50 can be integrally formed on the flange of the teat 12 , for example in the form of a stalk projecting downwardly of the teat at the teat aperture 51 . The teat 12 is mounted by screw collar 14 onto container 16 .
In a third embodiment of the present invention, as shown in FIG. 6 , the air conduit member 56 is integrally formed on a support member, for example in the form of a sealing ring 52 . The air conduit member 56 projects downwards of the sealing ring 52 . The sealing ring 52 is of similar diameter to container 16 and arranged to fit on the lip of the container to be gripped in a liquid tight condition by the flange of teat 12 pressed down by collar 14 . The sealing ring 52 additionally provides support for the flange of the teat 12 . A recess 55 is formed on the flange of the teat 12 which leads to an air inlet aperture 53 in the teat. An air passage is formed between the flange recess 55 and the screw collar 14 which allows for the passage of air from atmosphere through the aperture 53 on the flange of the teat, which is suitably aligned above the conduit member 56 on the ring 52 , and air conduit member 56 to the vent tube 22 , as shown by dotted arrow 54 . The vent tube 22 is attached to the air conduit member 56 with an airtight push fit.
FIGS. 7 a to 7 d show an alternative feeding bottle insert head portion 70 . As can be seen the head portion includes hub 71 connected to a rim 72 by spokes 73 . A liquid conduit is formed by spaces 74 between the hub 71 , rim 72 and spokes 73 . The liquid conduit provides communication between the container 16 and the teat 12 (neither shown) such that when the feeding bottle is inverted liquid passes from the container through the spaces 74 and into the teat allowing an infant to feed.
At least one of the spokes 75 is of sufficient thickness to allow a generally radial bore to be formed therethrough providing an air passage 76 to an open ended chamber 77 . The air passage 76 communicates the vent tube 22 (not shown), which is attached to an open ended chamber 77 by push fit and projects downwardly of the head portion 70 , to the atmosphere via the screw threads of the collar 14 (not shown).
An annular recess 78 in the underside of the generally annular shaped rim 72 provides a liquid tight seal between the head portion and the container 12 (not shown). The recess 78 is formed such that an inner surface 79 fits inside the container and an upper surface 80 rests on the lip of the container.
It will be appreciated that the various parts of the feeding bottles described above can be made with any appropriate material and in particular the teat 12 , collar 14 and container 16 can be made of any standard material. The vent tube 22 is preferably made of generally rigid, inert material such as plastics material and the valve 34 or 40 can be made of silicone rubber or other appropriate material for the purposes required. The flange 36 is preferably made of rigid plastic material allowing mixing and an anti-choke function and can be two-shot moulded with the valve 34 or 40 if appropriate. In the embodiments discussed various elements are connected by push fit allowing easy disassembly and cleaning but any appropriate manner of connection can be adopted and indeed where appropriate the various parts can be formed integrally or non-detachably. The head portion 20 is preferably of a semi-rigid material ensuring that the air passage 26 is not closed by deformation of the flange portion 28 but at the same time a reliable liquid tight seal is provided at the neck of the container. Similarly the support member of the third embodiment is preferably of a semi-rigid material ensuring that the air conduit member 56 is not closed by deformation when push fitted to the vent tube 22 but at the same time a reliable liquid tight seal is provided at the neck of the container 16 .
The neck insert 18 can be integral with the container/collar or can be detachable as appropriate for cleaning purposes. In particular the neck insert 18 can provide a simple modular attachment to a standard feeding bottle and in many cases the existing collar can be used in cooperation with the neck insert 18 . Alternatively the neck insert 18 can be provided with a specially tailored collar of appropriate depth to ensure good screw-thread engagement.
As a result of the arrangement described herein various advantages are provided. The valve allows natural feeding by venting at very low pressure. Because the vent tube 22 is valved at its base, pressure equalisation is provided within the container without allowing the infant to deform the teat and push liquid away from the teat. Also, because the valve provides a liquid seal there is no risk of leakage of liquid through the neck insert and down the side of the container. A simple and modular arrangement is provided for the neck insert. By virtue of the addition of a valve flange mixing and stirring can be improved whilst choke hazards can be avoided.
It will be appreciated by a skilled person that any appropriate type of valve can be used in place of the duck-billed valve or hemispherical valve described above. The dimensions of the container and the various components can be varied as appropriate and the specific positioning of the various elements can be rearranged as appropriate. Similarly any other appropriate shape and positioning of the valve flange can be adopted. Although the discussion above is directed to a feeding bottle a similar approach can be used in any drinking vessel with any type of mouthpiece or feeding or drinking closure where the desire is to provide pressure equalisation.
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A feeding bottle ( 10 ) comprises a container ( 16 ), a teat ( 12 ) and a collar ( 14 ) to screw the teat ( 12 ) onto and seal the container ( 16 ). A vent assembly ( 18 ) is mounted between the teat ( 12 ) and the container ( 16 ) and includes a vent tube ( 22 ) passing down to a position close to the base of the container ( 16 ) and having a one way valve ( 34 ) allowing air to pass into the container ( 16 ) on application of suction to the teat ( 12 ) but preventing liquid flowing into the vent tube ( 22 ), together with a valve flange ( 36 ) acting as an anti-choke member.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. §119 of a provisional application Ser. No. 60/971,790 filed Sep. 12, 2007, which application is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to the field of refrigerators. More specifically, this invention provides a refrigerator having a docking station for holding an electronic accessory flush against the door of the refrigerator.
BACKGROUND OF THE INVENTION
The statements in this section merely provide background information related to the present invention and may not constitute prior art.
With the coming of age of electronic devices, users and operators alike seek for new ways to accommodate or implement these devices in many different settings or places. For example, it is well known that over time kitchens have evolved to incorporate various electronic devices, such as radios, CD players, under-cabinet mounted CD and DVD players and the like. Refrigerators now incorporate various electronic devices. For example, the refrigerator may be configured with a docking station having a power connector for modules to plug into a variety of devices, such as an iPod docking station, cell phone charging/hands-free station, TV, digital picture frames, Web tablet, message board, DVD systems, and the like. However, the streamline aesthetics of modem refrigerators require that the fit between the docking station and the refrigerator be commercially acceptable. This being said, due to manufacturing variations, unacceptable gaps between the door and the electronic device may result rendering the refrigerator commercially unacceptable and aesthetically displeasing. Thus, the need to limit or significantly reduce gaps between the door of a refrigerator and an electronic device attached at the docking station of the refrigerator is a design feature that the present invention provides a solution for by providing a refrigerator having a docking station for holding an electronic accessory flush against the door of the refrigerator. Location and/or placement of the docking station relative to the door is critical to keeping the module or electronic device flush with the refrigerator door. Even though prefabricated holes in the top of the door may be available for attachment of the docking station, positioning the docking station relative to the door using these holes creates too much variation in fit as these holes are fashioned in the doors before subsequent manufacturing processes such as bending, shaping, or forming the door. Therefore, there is a need in the art to provide a refrigerator having a docking station for holding an electronic accessory flush against the door of the refrigerator. Additionally, current manufacturing tolerances for modules or electronic devices may exhibit variances and must be also considered to keep a nominal gap between the module and/or electronic device and the refrigerator door. For example, many electronic devices and modules are often constructed or manufactured as multi-piece structures which add to the variation and possible gap between the door of the refrigerator and the module or electronic device. Therefore, there is a further need to solve this problem, as well.
BRIEF SUMMARY OF THE INVENTION
The present invention relates to a refrigerator having a docking station for holding an electronic accessory tight against the door of the refrigerator. In one aspect of the present invention, a refrigerator is disclosed. The refrigerator includes a body having one or more doors, a docking station associated with the door and having a receiving portion adapted to receive a module, and at least one spring associated with the docking station adapted to keep the docking station and the module flush against the door to eliminate variation in fit between the module and the door. In a preferred form, the refrigerator also includes a magnetically-active plate positioned within the door whereby one or more magnets fitted at a bottom portion of the module are adapted to keep the bottom portion of the module snug against the door. A pole shoe may be mounted across the magnets to increase holding power and concentrate magnetic flux to prevent interference with the module. An abutment located on the module is shaped to mate within the docking station where the spring presses against the abutment to urge the module against the door to eliminate variation of fit between the module and the door. The docking station defines a top surface with parallel edges terminating in a pair of side walls, whereby one edge also includes a pair of spring levers extending generally downward from the edge and generally outward from the side wall. The door of the refrigerator has a cover with an inner and outer surface, whereby at least one of the springs keeps the docking station flush against the inner surface and another spring keeps the module flush against the outer surface.
In another aspect of the present invention, a refrigerator is disclosed having a body with one or more doors and an exterior surface. A docking station is positioned at the top of the door having a receiving portion adapted to receive a module. At least one pair of spring levers associated with the docking station are adapted to keep the docking station and the module flush against the exterior surface of the door to eliminate variation and fit between the module and the door. In a preferred form, the refrigerator also includes the module having an abutment adapted to be mateably received within the docking station, whereby the at least one pair of spring levers press against the abutment to urge the module flush against the exterior surface of the door.
In yet another aspect of the present invention, a refrigerator is disclosed. The refrigerator includes a body having one or more doors with an exterior surface, a magnetically-active plate positioned behind the exterior surface of the door adapted to receive a module, and a magnet associated with the module to keep the module flush against the exterior surface of the door to eliminate variation in fit between the module and the door. In a preferred form, the refrigerator includes a docking station with sidewalls connected by a bottom wall to form a receiving portion, the bottom wall having a pair of upwardly extending spring levers and a module having an abutment with a front side and an opposite back side, whereby the pair of upwardly extending spring levers are in contact with the front side of the abutment to bias the back side of the abutment against one sidewall to draw the module up flush against the door where the module is docked in the receiving portion.
Further areas of applicability of the present invention will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for the purposes of illustration only and are not intended to limit the scope of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present invention in any way.
FIG. 1A shows a front elevation view of a pair of refrigerators according to an exemplary embodiment of the present invention.
FIG. 1B is a sectional view taken along line 1 B- 1 B in FIG. 1A .
FIG. 1C is another embodiment of the electronic device shown in FIG. 1A .
FIG. 2A is a perspective view of the inner surface of the exterior portion of the refrigerator door having a docking station and other exemplary auxiliary components.
FIG. 2B is an exploded view of FIG. 2A .
FIG. 3 is an isometric view of the docking station according to an exemplary embodiment of the present invention.
FIG. 4 is a partial sectional view of the docking station and module positioned in the refrigerator door according to an exemplary embodiment of the present invention.
FIG. 5 is another partial cross-sectional view of the module and docking station mounted within the refrigerator door according to an exemplary embodiment of the present invention.
FIG. 6A is a front elevation, partial sectional view of the docking station mounted within the refrigerator door according to an exemplary embodiment of the present invention.
FIG. 6B is an isometric view of a snap of the docking station according to an exemplary embodiment of the present invention.
FIG. 7 is an isometric view of an adapter positioned at the bottom portion of the refrigerator door taken along line 7 - 7 in FIG. 2A .
FIG. 8A is a perspective view of the module according to an exemplary embodiment of the present invention.
FIG. 8B is a perspective view of another embodiment of the module shown in FIG. 8A .
FIG. 9A is an elevation view of the magnetic plate positioned on the inner surface of the exterior portion of the door according to an exemplary embodiment of the present invention.
FIG. 9B is a sectional view of the magnetic plate and door shown in FIG. 9A .
FIG. 10 is an illustration of several perspective views of the cap shown in FIGS. 1 and 1B according to an exemplary embodiment of the present invention.
FIGS. 11A-11C are side views showing alternative embodiments of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description is merely exemplary in nature and is not intended to limit the present invention, application, or uses.
The present invention provides a refrigerator having a novel docking station adapted to hold an electronic accessory and/or module tight against the door of the refrigerator. FIG. 1A illustrates a couple exemplary embodiments of the refrigerator 10 of the present invention. Generally speaking, the refrigerator 10 includes a refrigerator body 12 adapted to support one or more doors 14 . Each door 14 has a top 16 and an opposite bottom 18 . Door 14 also has a cover 24 which may be a door skin formed of a material such as plastic, stainless steel or the like. Each door 14 has an exterior side 20 and an opposite interior side 22 . The exterior side 20 of the cover 24 of the door 14 has an inner surface 26 and an outer surface 28 , as best illustrated in FIGS. 1A-2B . Similarly, the interior side 22 of the cover 24 of the door 14 also has an inner surface 26 and an opposite outer surface 28 .
Fashioned into the top 16 of the door 14 is a docking station 100 , as best illustrated in FIGS. 2A-6A . The docking station 100 may be adapted to receive a cap 30 , as shown in FIG. 1B , and FIG. 10 or an electronic device 226 , as shown in FIGS. 1A and 1C . Even though the docking station 100 is shown on only one door 14 of the refrigerator 10 , it should be appreciated by those skilled in the art that the docking station 100 could be fashioned into either one or both doors 14 of refrigerator 10 .
FIGS. 2A and 2B best illustrate how the docking station 100 may be incorporated into the door 14 of the refrigerator 10 . FIGS. 2A and 2B illustrate generally the inner surface 26 of the exterior side 20 of the door 14 . Positioned at the top 16 of the door 14 is docking station 100 . A pair of wires 126 ingress door 14 at bottom 18 by way of adapter 38 . In one aspect of the present invention, adapter 38 may be a cam adapter whereby the adapter is rotated or twisted to lock the position of the adapter 38 relative to the bottom 18 of the door 14 . Wires 126 extend from the adapter 38 up to the docking station 100 . Wires 126 may be configured to provide power at the docking station 100 and/or transfer an electrical signal from or to the docking station 100 .
FIG. 3 shows a perspective view of one embodiment of the docking station 100 according to an exemplary aspect of the present invention. The docking station 100 in one aspect has a generally u-shaped member supporting a receiving portion 102 . The u-shaped member has a top surface 106 with opposite parallel edges 108 terminating in sidewalls 110 . Each sidewall 110 extends in a generally perpendicular direction away from the top surface 106 of the docking station 100 . A pair of spring levers 112 is configured into at least one sidewall 110 . The spring levers 112 extend in a generally downward direction from edge 108 and in a generally outward direction from sidewall 110 so as to be angled away from sidewall 110 . Each spring lever 112 positioned in sidewall 110 of the docking station 100 may also include a catch 116 . Spring levers 112 configured into the sidewall 110 of the docking station 100 contact the inner surface 26 of the interior side 22 of the cover 24 of the door 14 , as best illustrated in FIG. 4 . The pressure of spring lever 112 configured into the sidewall 110 of the docking station 100 acting on the inner surface 26 of the interior side 22 of the cover 24 of the door 14 biases the opposite sidewall 110 against the inner surface 26 of the exterior side 20 of the cover 24 of the door 14 . Thus, spring lever 112 configures into the sidewall 110 of the docking station 100 insures that the docking station 100 is correctly positioned within and relative to the door 14 .
In another aspect of the docking station 100 , the docking station 100 includes a receiving portion 102 formed by a plurality of sidewalls 103 attached to a bottom wall 104 . The receiving portion 102 of the docking station 100 is cup-shaped and thereby adapted to house, receive, and mate with a top portion 208 of the module 200 . Positioned on the bottom wall 104 of the docking station 100 is a pair of upwardly extending spring levers 112 . Spring levers 112 extend upwardly from the bottom wall 104 of the docking station 100 in a generally perpendicular direction. Each spring lever 112 has a larger cross-sectional area at its base, which tapers to a smaller cross-sectional area at its tip. As shown in FIG. 5 , spring lever 112 extending from the bottom wall 104 of the docking station 100 is configured to contact and apply pressure to the front side 220 of each abutment 214 of the module 200 . Thus, spring lever 112 , shown in FIG. 5 , biases or urges the back side 222 of the abutment 214 against the sidewall 103 of the docking station 100 by shifting or urging the docking station 100 rearward along arrow 224 . The biasing or urging of the module 200 rearward against the sidewall 103 of the docking station 100 causes the back side 206 of the module 200 , shown in FIGS. 8A and 8B , to be pulled up flush against the outer surface 28 of the exterior side 20 of the cover 24 of the door 14 , as best illustrated in FIG. 4 . Thus, both sets of spring levers 112 (i.e., spring lever 112 extending upwardly from the bottom wall 104 of the docking station 100 and spring levers 112 extending from the edge 108 of the top surface 106 of the docking station 100 ) help to correctly position the docking station 100 within and relative to the door 14 as well as correctly position the module 200 relative to the docking station 100 and the outer surface 28 of the exterior side 20 of the cover 24 of the door 14 . Also, configured into the bottom wall 104 of the docking station 100 is a pair of posts 130 . Posts 130 are used to secure mounting plate 120 to the bottom wall 104 of the docking station 100 , as best illustrated in FIG. 6A . A recess 132 having an aperture 134 is also configured into the bottom wall 104 of the docking station 100 , as shown in FIGS. 3 and 6A . Wires 126 pass through the aperture 134 and the recess 132 of the docking station 100 . These wires 128 are connected to a connector 122 mounted in the mounting plate 120 . Connector 122 has a plurality of contact pins 124 adapted to mate with connector 218 of the module 200 . The connector 122 may be rigidly fixed to the mounting plate 120 or floatably connected to the mounting plate 120 whereby the connector 122 may shift accordingly to mate with connector 218 of the module 200 . Alignment pins 128 may also be used to help align connector 218 of the module 200 with connector 122 of the docking station 100 . Several other features configured into the top surface 106 of the docking station 100 are used for connecting the docking station 100 to the top 16 of the door 14 . For example, snaps 114 positioned on the top surface 106 of the docking station 100 extend through apertures 36 , as best illustrated in FIG. 2B , in the top 16 of the cover 24 of the door 14 to help secure the docking station 100 to the door 14 . Additionally, cavities 118 may be configured into the top surface 106 of the docking station 100 for receiving a coupler nut (not shown) that extends through an aperture in the top 16 of the cover 24 of the door 14 to aid in securing the docking station 100 to the door 14 , as best illustrated in FIGS. 3 and 6A .
FIGS. 8A and 8B best illustrate the module 200 according to an exemplary embodiment of the present invention. The module 200 has a top portion 208 and an opposite bottom portion 210 . As previously discussed, the module 200 has a pair of abutments 214 extending in a generally perpendicular direction from the top portion 208 of the module 200 . A connector 218 is also configured into the top portion 208 of the module 200 . Connector 218 mates with connector 122 in the docking station 100 when the module 200 is docked within the docking station 100 . Similarly, the back side 222 of each abutment 214 is urged rearward against the sidewall 103 of the docking station 100 by a spring lever 112 acting on the front side 220 of the pair of abutments 214 , as shown in FIG. 5 . Apertures 216 are configured into the top portion 208 of module 200 to aid in securing the module 200 to the docking station 100 when the module 200 is docked within the docking station 100 . As also previously mentioned, the pair of abutments 222 acted on by the pair of spring levers 112 extending upwardly from the bottom wall 104 of the docking station 100 help to draw the top portion 208 of the back side 206 of the module 200 up flush against the outer surface 28 of the exterior side 20 of the cover 24 of the door 14 . To aid in drawing the bottom portion 210 of the module 200 up flush against the outer surface 28 of the door 14 , a corresponding pair of fasteners 205 , 207 may be positioned in or on the bottom portion 210 of the module 200 and on the door 14 , as best shown in FIG. 11 C. Preferably one or more magnets 202 may be positioned in the module 200 , and a magnetically-active medium such as plate 32 , shown in FIG. 9A , may be positioned on the inner surface 26 of the exterior side 20 of the cover 24 of the door 14 . Plate 32 may be any type of material that is magnetically-active, such as a ferrous metal and may be attached by way of adhesive 34 . Plate 32 provides a magnetically-active medium for each magnet 202 in module 200 to be attracted to. For example, if the cover 24 of the door 14 is a stainless steel material, plate 32 provides a magnetically-active member for magnets 202 on the module 200 to be attracted to draw the bottom portion 210 of the module 200 up flush against the outer surface 28 of the door 14 . In another aspect of the present invention, the magnets 202 , as shown in FIG. 9B , may include a pole shoe 204 connected across the pair of magnets 202 to increase the holding power and concentrate magnetic flux 212 so that it is less likely to interfere with module 200 . While magnets 202 are preferred to aid in drawing the bottom portion 210 of the module 200 up flush against the outer surface 28 of the door 14 , it is recognized that other fastening devices such as suction cups 201 , hook-and-loop fasteners 203 such as Velcro® or any other fastening device could be used, as shown in FIGS. 11A and 11B . Furthermore, module 200 , as shown in FIGS. 1A , 1 C, 8 A, and 8 B, may be any electronic device 226 capable of being connected to the module 200 or docked within the docking station 100 of the present invention. For example, a variety of devices such as an iPod docking station, cell phone charging/hands-free station, TV, digital picture frame, Web tablet, message board, DVD system, and the like may be connected to the module 200 and/or docked within the docking station 100 of the present invention. By way of further example, FIGS. 1A and 1C show the electronic device 226 being an LCD panel and neon sign, respectively. Although several examples of electronic devices are disclosed, these electronic devices 226 are used only by way of example, as the docking station 100 and the module 200 may be configured to accommodate a wide variety of various electronic devices not limited to any specific use, scope, or application.
FIG. 10 shows various views of a cap 30 of the present invention. Cap 30 is a generally L-shaped member adapted to insert within and cover the docking station 100 of the present invention. Cap 30 may include recessed apertures 40 whereby a locking nut may be inserted through each recess aperture 40 and the cap 30 into one of the cavities 118 in the top surface 106 of the docking station 100 to secure the cap 30 to the door 14 of the refrigerator 10 . An abutment 34 may also be configured into the cap 30 to help in correctly positioning the cap relative to the docking station 100 and/or the door 14 . For example, the abutment 44 may be received within the receiving portion 102 of the docking station 100 to help align the cap 30 relative to the docking station 100 and the door 14 of the refrigerator 10 , as shown in FIG. 1A . The cap 30 may further include indicia 42 , such as raised lettering, on a surface on the cap 30 , as shown in FIGS. 1A and 10 .
The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the gist of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure. Changes in the formed proportions of parts, as well as in substitutions of equivalents are contemplated as circumstances may suggest or are rendered expedient without departing from the spirit and scope of the invention as further defined in the following claims.
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The present invention provides a refrigerator having a docking station for holding electronic accessories tight against the door of the refrigerator. In one aspect of the present invention, the refrigerator includes a body having one or more doors, a docking station associated with the door, and having a receiving portion adapted to receive a module, and at least one spring associated with the docking station adapted to keep the docking station and the module flush against the door to eliminate variation and fit between the module and the door.
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BACKGROUND OF THE INVENTION
The present invention relates to a process and apparatus for spinning a multi-filament yarn, of the general type disclosed in U.S. Pat. No. 4,529,368.
The process of the present invention is distinguished by the fact that, after emerging from the spinneret, the filaments are not subjected directly to cross-flow blowing of cooling air. Rather, the filaments first pass through a first cooling zone with a view to stabilizing the cross-section of the yarn. By this construction, a high degree of uniformity of the filaments is achieved.
However, in the course of further cooling in a second cooling zone, at a preset draw-off speed of 3,000 m/min for example, the chains of molecules are frozen with a pre-orientation. The pre-orientated yarn (POY) produced in this way displays a reduced elongation at break and hence reduced stretchability in the subsequent treatment process.
EP 0 334 604 discloses a process in which, after emerging from the spinneret, the filaments directly enter a blowing stage. In this connection the filaments are cooled with tempered air, whereby a weaker cooling effect is sought in the upper region than in the lower region.
A process is also described in EP 0 726 338 and corresponding U.S. Pat. No. 5,661,880 in which the filaments are additionally warmed immediately upon emerging from the nozzle plate of the spinneret.
In both processes the filaments are blown directly with a current of air with a view to cooling, so that irregularities arise, particularly in the case of thin filaments.
It is accordingly an object of the present invention to provide an improved process of the type described above, as well as an apparatus for the application of the process in such a way that it is possible to produce a yarn having a high degree of uniformity and a high stretching capacity--i.e., a high elongation at break.
SUMMARY OF THE INVENTION
The above and other objects and advantages of the present invention are achieved by the provision of a process and apparatus wherein the heated and melted thermoplastic polymer is extruded through a plurality of apertures in a nozzle plate of a spinneret to form a plurality of downwardly advancing filaments. The filaments are serially (1) cooled by passing the advancing filaments through a first cooling zone disposed immediately below the nozzle plate, (2) warmed by passing the advancing filaments through a heating zone disposed immediately below the first cooling zone, and (3) cooled by passing the advancing filaments through a second cooling zone immediately below the heating zone. The advancing filaments are then gathered together to form an advancing multi-filament yarn, which may then be wound into a package.
With the process according to the invention the filaments emerging from the nozzle plate are first cooled in the first cooling zone, which ensures that the filament skin initially solidifies. It is consequently no longer possible that the molten filament deliquesces--i.e., forms thicker or thinner portions. Also, a high degree of uniformity of the filaments is achieved. In the further course of the process, the yarn is then warmed in a heating zone to a temperature lying within the plastification range of the polymer but below the solidification temperature. By this arrangement, the frozen chains of molecules are broken open again, so that the mobility of the chains of molecules results in disorientation. The filaments are subsequently cooled again in the second cooling zone.
The process according to the invention has the advantage that as a result of the disorientation, an increase in the elongation at break of the yarn is achieved and hence, for a preset draw-off speed, subsequent stretchability of the yarn can be increased.
The warming of the filaments in the heating zone is advantageously effected by irradiation. In this connection use is preferably made of radiant heaters having a surface temperature of more than 400° C.
In the course of heating up the filaments by the combination of irradiation with a current of cooling air, the current of cooling air prevents the hot air that leaves the heating zone from reaching the cooling region of the first cooling zone.
The process variant in which the cooling of the filaments in the first cooling zone is effected with the aid of weak blowing of air should be used in particular for the production of technical yarn.
The cooling of the filaments in the second cooling zone can be effected both with air blowing and without air blowing. Depending on the combination, the physical properties of the yarn can consequently be adjusted advantageously.
With a view to warming the filaments in the heating zone it is advantageous that the apparatus according to the invention comprise radiant heaters on both sides of the bundle of advancing filaments. In one preferred embodiment, the bundle of filaments is enveloped by the radiant heater which results in particularly uniform warming of the filaments.
In another preferred embodiment, the radiant heaters are arranged in the form of heated reflector plates in the cooling shaft. In this connection, it is advantageous if an already warmed current of air is supplied by a cross-flow blowing stage. By means of the reflector plates the current of air that has been cooled by the bundle of filaments is heated again and guided back to the bundle of filaments. By this arrangement, a high degree of uniformity of the heat treatment of the filaments is achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
Some of the objects and advantages of the present invention having been stated, others will appear as the description proceeds, when considered in conjunction with the accompanying schematic drawings, in which:
FIG. 1 is an illustration of a melt spinning apparatus which incorporates the features of the present invention;
FIG. 2 is a sectional side elevation view of a cooling shaft for the melt spinning in accordance with one embodiment of the invention;
FIG. 3 is a transverse sectional view of another embodiment of the cooling shaft of the present invention; and
FIG. 4 is a view similar to FIG. 2 and illustrating another embodiment of the cooling shaft of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Shown schematically in FIG. 1 is a spinning apparatus that consists of a spinning zone I, a drawing zone II, and a winding zone III. In this connection the thermoplastic polymer is fed into the extruder 3 by a filling device. The extruder 3 is driven by a motor 4 which is controlled by a motor control system 8. The thermoplastic polymer is heated and melted in the extruder. This purpose is achieved, on the one hand, by the deformation work that is introduced into the material by the extruder. In addition a heating device 5 in the form of a resistance heating unit is provided which is controlled by means of a heating control system 43. Through the melt pipe the melt reaches the gear pump 9 which is driven by the pump motor 44. The pressure of the melt ahead of the pump is detected by the pressure transducer 7 and kept constant by feedback of the pressure signal to the motor control system 8.
The pump motor is controlled by the pump control system 45 in such a way that the rotational speed of the pump is capable of sensitive adjustment. The pump 9 conveys the current of melt to the heated spinneret 10, on the underside of which an apertured nozzle plate 11 is located in a nozzle pot 53. From the nozzle plate 11, the melt emerges in the form of fine filaments 12. The filaments 12 then advance downwardly through a cooling shaft 14 for cooling the filaments, and which is arranged vertically below the nozzle plate 11. The filaments 12 first enter a first cooling zone 46 which in the embodiment of FIG. 1 is bounded by air impermeable walls. Directly connected below the first cooling zone is a heating zone 47, in which the filaments 12 are heated up by means of a radiator 52. Directly connected below the heating zone is a second cooling zone 48, in which a current of air is directed transversely in relation to the advance of the filaments through an air permeable blow wall. For this purpose, the air permeable blow wall is connected to an air supply 15.
At the end of the cooling shaft 14 the filament bundle is combined by means of a preparation roller 13 to form a yarn 1 and is provided with a processing liquid. The yarn 1 then enters the drawing zone II. In this connection, the yarn 1 is drawn out of the cooling shaft 14 and from the spinneret by means of a draw-off godet 16. The yarn wraps repeatedly around the draw-off-godet. This purpose is served by an overflow roller 17 that is arranged crosswise in relation to the godet 16, and which is freely rotatable. By means of the godet motor 18 and the frequency transmitter 22 the godet 16 is driven at a speed that is capable of being preset. This draw-off speed is higher by a multiple than the natural discharge speed of the filaments from the spinneret 11. By adjustment of the initial frequency of the frequency converter 22 it is possible for the rotational speed of the draw-off godet 16 to be set. By this arrangement, the draw-off speed of the yarn 1 from the nozzle plate 1 is determined. The draw-off godet 16 is followed by a stretching godet 19 with an additional overflow roller 20. Both correspond in their construction to the draw-off godet 16 and the overflow roller 17. The stretching motor 21 with the frequency transmitter 23 serves to drive the stretching godet 19. The initial frequency of the frequency converters 22 and 23 is preset uniformly by the controllable frequency transmitter 24. In this manner the rotational speeds of the draw-off godet 16 and of the stretching godet 19 can be set individually with the aid of the frequency converters 22 and 23. The speed level of the draw-off godet 16 and the stretching godet 19, on the other hand, is set collectively by the frequency converter 24.
From the stretching godet 19 the yarn 1 runs into the winding zone III and there to the top thread guide 25 and from there into the traversing triangle 26. The yarn then runs into a traversing device (not shown), wherein the yarn is guided to and from along a traversing stroke by means of guide elements. In this connection the traversing device may be constructed in the form of an inverse thread roller with a traversing thread guide borne thereon or in the form of a flyer traversing device. From the traversing device the yarn runs via a contact roller 28 to the package 33 that is to be wound. The contact roller 28 rests in close contact with the surface of the package 33, and it serves for measuring the surface speed of the package 33. The package 33 is formed on a tube 35, which is coaxially mounted upon a winding spindle 34. The spindle 34 is driven by the spindle motor 36 and the spindle control system 37 in such a way that the surface speed of the package 33 remains constant.
To this end, by way of controlled process variable, the rotational speed of the freely rotatable contact roller 28 on the contact roller shaft 29 is scanned and fully controlled by means of a ferromagnetic insert 30 and a magnetic pulse generator 31.
The process according to the invention for spinning a multi-filament yarn is not restricted to the arrangement shown in FIG. 1. In principle the process may also be carried out in an arrangement of the type in which the drawing zone II comprises only a draw off godet. It is also possible to operate the spinning zone I directly with the winding zone III--that is to say, without any godet.
FIG. 2 illustrates another embodiment for cooling the filaments in the spinning zone in accordance with the invention. Directly below the nozzle plate 11, a cooling shaft 14 that receives the filaments 12 is formed by blower casings 54 and 64 arranged on both sides. Immediately below the nozzle plate 11 the blower casings 54 and 64 comprise the air impermeable side walls 51 and 61. The side walls 51 and 61 form the first cooling zone. Depending on polymer type and yarn type, the first cooling zone has a length of about 250 mm to 500 mm.
Below the side walls 51 and 61 several radiant heaters 52.1, 52.2, 52.3 and 62.1 to 62.3 are arranged, located opposite one another and directed towards the filaments. In this connection the radiant heaters 52.1-52.3 and 62.1-62.3 are arranged in the cooling shaft 14 underneath one another parallel to the bundle of filaments 12 subject to a spacing in relation to one another, so that an intake of air between the radiant heaters into the cooling shaft 14 becomes possible. The radiant heaters preferably have a surface temperature lying above 400° C. Below the radiant heaters the cooling shaft 14 is formed by air permeable side walls 53 and 50. The blower casing 54 and the blower casing 64 are in each instance connected to an air supply 15. The air that is blown in now extends into the cooling shaft 14 via the spaces between the radiant heaters 52.1-52.3 and 62.1-62.3 and through the air permeable blow walls 53 and 50. Arranged below the cooling shaft 14 is the preparation roller 13, where the bundle of filaments 12 is combined to form a yarn 1.
FIG. 3 illustrates one embodiment for the cross-section of the heating zone of a blower chamber 54. In this connection, the bundle of filaments 12 passes through the cooling shaft 14, and the cooling shaft 14 is bounded by the side walls 57 and 58. The blower casing 54 includes a wall 53 which is arranged in relation to the bundle of filaments in such a way that the in flowing air in the blower casing 54 flows through the wall 53 and along the side walls 57 and 58 transversely in relation to the filaments. Arranged opposite the wall 53 on the opposite side of the bundle of filaments is a reflector plate 55. The reflector plate is heated by means of a resistance heating wire 56. Hence a direct heating of the filaments and also a warming of the cooling air that flows back is generated.
FIG. 4. illustrates another embodiment of the cooling shaft of the present invention. In comparison with the arrangement shown in FIG. 2, the side walls 51 and 61 of the cooling shaft 14 are constructed to be air-permeable directly below the nozzle plate 11. The radiant heaters 52.1-52.3 and 62.1-62.3 arranged on both sides of the bundle of filaments are also once again arranged so as to be axially spaced apart. This makes it possible for the ambient air to flow into the cooling shaft and consequently, particularly in the first cooling zone, results in a better cooling effect. In this connection the blower casing 59 is arranged below the first cooling zone 46 and the heating zone 47. The blower casing 59 is connected to the air supply 15. The walls 53 and 50 are air permeable, so that a current of air flows out of the casings 59 and 60 into the cooling shaft 14 transversely in relation to the bundle of filaments 12. Below the cooling shaft 14 a preparation device 13 is again arranged in order to form the yarn 1.
In the case of the processes with high draw-off speeds the second cooling zone 48 is also advantageously designed in such a way that self-generating current of air is drawn into the cooling shaft 14. In this case an active blowing stage would be unnecessary.
Another advantageous further development of the process is constituted by a variant wherein the current of air is blown into the cooling shaft 14 from below, which consequently flows opposite the direction of the advance of the yarn.
With the process of the present invention it has been shown that the elongation at break of the yarns is increased by >5%. The increase in stretchability is accordingly also augmented by >5%.
In the drawings and specification, there has been set forth a preferred embodiment of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.
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A process and apparatus for cooling freshly spun polymeric filaments as part of the formation of a multi-filament yarn, wherein the filaments are passed serially through a first cooling zone, a heating zone, and a second cooling zone. The resulting filaments have an improved elongation at break and an improved stretchability.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the national phase filing of international patent application No. PCT/EP2010/061487, filed 6 Aug. 2010, and claims priority of German patent application number 10 2009 028 339.0, filed 7 Aug. 2009, the entireties of which applications are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to a bioreactor that is provided with silicones, method of production of bioreactors, and the use of silicones for the production of bioreactors.
BACKGROUND OF THE INVENTION
[0003] Bioreactors are used for large-scale industrial production of phototrophic organisms, e.g. cyanobacteria or microalgae, for example Spirulina, Chlorella, Chlamydomonas or Haematococcus. These microalgae are able, with the aid of light energy, to convert CO 2 and water into biomass. Photobioreactors of the first generation use sunlight as the light source. The reactors consist of large open tank units of various shapes, for example round tanks with diameters of up to 45 m and rotating stirring arms. These reactors are generally made of concrete or plastics. Closed bioreactors are also used in many different forms. Closed bioreactors can be plate-type bioreactors, tubular bioreactors, (bubble) column bioreactors or hose-type bioreactors. This type of reactor is made of transparent or translucent materials, such as glass or plastic.
[0004] To date, the culture conditions of phototrophic microorganisms, which are produced in closed reactors, cannot be kept constant for an extended period, as the phototrophic microorganisms that form in a culture phase are deposited on the reactor walls, which leads to fluctuations in the amount of light supplied to the culture medium and to variable mixing of the culture medium. Algal deposits are often caused by stress conditions during cultivation, the causes of which can be uncontrolled growth conditions (e.g. light, temperature in open-pond and in closed reactors) of the microorganisms or induction of the production of valuable substances by the phototrophic organisms (e.g. astaxanthin, beta-carotene).
[0005] WO 2007/129327 A1 relates to a photobioreactor for cultivation of biomass, which is constructed of transparent, helically-coiled tubes. Silicone is generally recommended as tube material, and there is no discussion of the fouling problem. The illumination of photoreactors with LED plastic moldings is described in WO 2008/145719. Steel, plastics and ceramics are listed as reactor materials. The illuminating element is preferably an LED silicone molding. WO 2004/108881 A2 includes a bioreactor arrangement of vessel and light source, and all possible plastics, including silicones that are not specified in greater detail, are stated as materials for the vessel. WO 2009/037683 A1 describes a bathtub-shaped bioreactor with umbrella-shaped cover made of transparent materials, which are not further specified. Gas-permeable hoses, preferably of silicone, are used for feed of carbon dioxide. GB 2118572 A describes a photobioreactor with glass tubes, which are joined with U-shaped connectors made of silicone. DE 10 2005 025 118 A1 describes a photobioreactor made of glass tubes, wherein microorganisms that have accumulated on surfaces are removed by means of ultrasound. US 2003/0073231 A1 describes a photobioreactor made of thermoplastics such as polyvinyl chloride or polyethylene. The object of US 2007/0048848 A1 is also a photobioreactor made from thermoplastics. In both cases, deposits of microorganisms on the reactor walls are removed by mechanical means, for example brushing. These are in all cases relatively expensive methods, which cannot be scaled up as desired. In DE 44 16 069 A1 it is recommended to provide light-conducting fibers, which are used for illuminating bioreactors, with a smooth surface. US 2008/0311649 A1 proposes increasing the flow rate of the medium containing the algae in tubular bioreactors, to prevent deposition of the algae. This has the disadvantage that the culture parameters with respect to flow rate can no longer be set independently.
SUMMARY OF THE INVENTION
[0006] Against this background, the problem to be solved was to improve bioreactors for cultivation of microorganisms, so that fouling with microorganisms on the reactor parts coming into contact with the culture medium is largely prevented, and any fouling that does occur can be removed inexpensively. The solution should not have a negative effect on product quality, it should be up-scalable, and should be capable of universal application, independently of the process parameters required for cultivation.
[0007] The invention relates to a bioreactor for the cultivation of phototrophic organisms in an aqueous culture medium, in which reactor parts coming into contact with the culture medium are made completely or partially from silicone materials, characterized in that the silicone materials are made from addition-crosslinked silicones, and the surface of the silicone materials has a contact angle with water of at least 100°.
DETAILED DESCRIPTION OF THE INVENTION
[0008] Organisms suitable for cultivation are in particular phototrophic macro- or microorganisms. Phototrophic organisms are designated as those that require light and carbon dioxide, or optionally another carbon source as well, for growth. Examples of phototrophic macroorganisms are macroalgae, plants, mosses, plant cell cultures. Examples of phototrophic microorganisms are phototrophic bacteria such as purple bacteria and phototrophic microalgae including cyanobacteria. Preferably the bioreactor is used for the cultivation of phototrophic microorganisms, especially preferably the cultivation of phototrophic microalgae.
[0009] The bioreactor can be a closed reactor or an open reactor, in each case of any desired shape. For example, in the case of open reactors it is possible to use tanks or so-called “open ponds” or “raceway ponds”. Closed reactors are preferred as bioreactors. The closed bioreactors can be for example plate-type bioreactors, tubular bioreactors, (bubble) column bioreactors or hose-type bioreactors. Plate-type bioreactors consist of perpendicular or slanting brick-shaped plates, with a large number of plates joined together to form a quite large reactor system. Tubular bioreactors consist of a tube system, which can be arranged vertically or horizontally or at any angle in between, and the tube system can be very long, preferably up to several hundred kilometers. The culture medium is then transported through the tube system, preferably by means of pumps or by the air-lift principle. The column bioreactor consists of a closed, cylindrical vessel, which is filled with the culture medium. In bioreactors of this type, carbon dioxide is introduced, and the ascending bubble column provides mixing of the culture medium. Hose-type reactors comprise a reactor system that consists of a single hose of any length or a large number of hoses of any length, preferably of hoses up to several meters long.
[0010] The bioreactors are preferably made of transparent or translucent, addition-crosslinked silicone materials. Transparent silicone materials are to be understood as those that let through at least 80% of the light in the spectral range from 400 nm to 1000 nm. Translucent silicone materials are to be understood as those that let through at least 50% of the light in the spectral range from 400 nm to 1000 nm. Reactor parts mean the reactor walls including reactor bottom and reactor cover and structure-forming elements in the culture medium, for example baffles. In the case of tubular, plate-type and hose-type reactors, the tubes, plates and hoses correspond to the reactor walls. The reactor walls are preferably made completely or partially of silicones. Especially preferably, in the case of tubular reactors or plate-type reactors, the tubes or plates are made of addition-crosslinked silicones. In the case of column reactors, the cylindrical vessels are made of addition-crosslinked silicones.
[0011] Suitable silicones for the production of bioreactors are addition-crosslinking silicones, wherein the addition crosslinking can be initiated thermally or by means of radiation. Peroxide-crosslinked silicones have the disadvantage that these silicones have greater stickiness in the crosslinked state than addition-crosslinked silicones.
[0012] Addition-crosslinking silicone rubber systems contain
[0013] a) organosilicon compounds, which have residues with aliphatic carbon-carbon multiple bonds,
[0014] b) optionally organosilicon compounds with Si-bound hydrogen atoms or instead of a) and b)
[0015] c) organosilicon compounds, which have residues with aliphatic carbon-carbon multiple bonds and Si-bound hydrogen atoms,
[0016] d) catalysts promoting the addition of Si-bound hydrogen on aliphatic multiple bonds and
[0017] e) optionally agents delaying the addition of Si-bound hydrogen on aliphatic multiple bonds at room temperature.
[0018] Suitable silicone rubbers crosslinking by an addition reaction are high-temperature vulcanizing (HTV) solid silicone rubbers.
[0019] Addition-crosslinked HTV silicone rubbers are obtained by crosslinking of organopolysiloxanes multiply substituted with ethylenically unsaturated groups, preferably vinyl groups, with organopolysiloxanes multiply substituted with Si—H groups in the presence of platinum catalysts.
[0020] Preferably one of the components of the addition-crosslinking HTV-2 silicone rubbers consists of dialkylpolysiloxanes of structure R 3 SiO[—SiR 2 O] n —SiR 3 with n≧0, generally with 1 to 4 carbon atoms in the alkyl residue R, wherein the alkyl residues can be replaced completely or partially with aryl residues such as the phenyl residue and at one or at both ends one of the terminal residues R is replaced with a polymerizable group such as the vinyl group. However, polymers with side or with side and terminal vinyl groups can also be used. Preferably vinyl end-blocked polydimethylsiloxanes of structure CH 2 ═CH 2 —R 2 SiO [—SiR 2 O] n —SiR 2 —CH 2 ═CH 2 are used, and vinyl end-blocked polydimethylsiloxanes of the aforesaid structure, which also bear vinyl side groups. In the case of addition-crosslinking HTV silicone rubbers, the second component is a copolymer of dialkylpolysiloxanes and polyalkylhydrogensiloxanes with the general formula R′ 3 SiO[—SiR 2 O] n —[SiHRO] m —SiR′ 3 with m≧0, n≧0 and R with the meaning given above and with the proviso that at least two SiH groups must be contained, wherein R′ can have the meaning of H or R. There are accordingly crosslinking agents with side and terminal SiH groups, whereas siloxanes with R′═H, which only have terminal SiH groups, can also still be used for chain extension. Platinum catalysts can be used as crosslinking catalysts. HTV silicone rubbers are also processed as a one-component system.
[0021] Other suitable materials are crosslinked silicone hybrid materials, as described in WO 2006/058656, the relevant information of which is incorporated by reference in this application.
[0022] A detailed review of silicones, their chemistry, formulation and application properties is given for example in Winnacker/Küchler, “Chemische Technik: Prozesse and Produkte, Vol. 5: Organische Zwischenverbindungen, Polymere”, p. 1095-1213, Wiley-VCH Weinheim (2005).
[0023] The surface morphology of the silicone moldings is important for the inhibition or prevention of fouling with microorganisms. The surface morphology is determined from the contact angle of said surface with water. The contact angle according to the invention is adjusted by selection of the silicone materials according to the invention. Further measures for increasing the contact angle, for example roughening of the surface (e.g. simulation of the so-called lotus effect), are preferably ignored. In fact such roughening can disturb the cultivation of phototrophic microorganisms. Surfaces with contact angles between 100° and 120° are preferred, surfaces with contact angles between 100° and 115° are especially preferred, and surfaces with contact angles between 100° and 113° are quite especially preferred. The contact angle of the surface of the silicone moldings with water can be determined by methods known by a person skilled in the art, for example according to DIN 55660-2, using commercially available measuring instruments for determining the contact angle, for example the contact angle measuring systems obtainable from the company Krüss.
[0024] Optionally the addition-crosslinked silicones can contain usual additives for promoting adhesion or usual fillers or fiber materials for improving the mechanical properties. These additives are preferably used in maximum amounts such that the silicone molding remains transparent or translucent. Light-conducting additives and light wave-displacing additives can also be added.
[0025] The reactor parts coming into contact with the culture medium, in particular the reactor walls, are made at least partially, preferably completely, from the aforementioned addition-crosslinked silicones. Manufacture can take place with the established technologies for plastics processing, which are used for the production of molded bodies such as plates, hoses, tubes or containers of any shape; for example by means of extrusion for making plates, tubes, hoses, or injection molding.
[0026] Laminates can also be produced, which consist of a composite of an addition-crosslinked silicone molding and of a glass or plastic molding, i.e. a laminate with materials that have been used until now for the production of bioreactors. Examples of conventional materials for bioreactors are glass or plastics such as polymethyl methacrylate (Plexiglas), polyesters such as PET, polycarbonate, polyamide, polystyrene, polyethylene, polypropylene, polyvinyl chloride. With these laminates, it is possible to make bioreactors whose interior, i.e. the side facing the cultivation medium, consists of addition-crosslinked silicone.
[0027] The bioreactors are equipped with reactor fittings; for example, for filling and supply of nutrients, with feed lines and, for product separation and emptying, with discharge lines (e.g. for salt and feed solutions). For cooling and heating, the bioreactors can optionally be equipped with heating and cooling devices such as heat exchangers. Moreover, the bioreactors can also contain stirring devices and pumps for mixing. Bioreactors are often also equipped with devices for artificial illumination. Further examples of reactor devices are measuring and control instruments for monitoring operation (e.g. analysis of pH, O 2 , CO 2 , ion conductivity, luminous intensity). In a preferred embodiment the reactor fittings are also coated completely or partially with silicone.
[0028] The photobioreactors made from addition-crosslinking silicone moldings, with surfaces with a contact angle with water with values of at least 100°, minimize the deposition of the phototrophic organisms that form, so that the flow conditions of the culture medium remain constant, and the light input that is ideal for growth remains set at optimal growth. The surface finish of the silicone moldings according to the invention with a contact angle with water of at least 100° on the one hand reduces the accumulation of water on the silicone surface, and on the other hand substances dissolved in water, which for example arise through stress situations during cultivation of the algae, are kept away from the surface.
[0029] Moreover, expenditure on cleaning between individual cultivation cycles and on changing the phototrophic organisms to be cultivated is minimized. Any organisms adhering to the coated surfaces can be removed between the cultivation cycles by spraying with a cleaning agent for example with water, ethanol or H 2 O 2 without further mechanical treatment. This leads to substantial economic advantages on account of shorter downtime and lower cleaning costs. Another advantage is the high UV-stability of addition-crosslinked silicones with the surface finish according to the invention, which, especially in an outdoor setting, greatly increases the service life of bioreactors made of addition-crosslinked silicone materials with the surface finish according to the invention compared with bioreactors made from conventional plastics.
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The invention relates to a bioreactor for cultivating phototrophic organisms in an aqueous culture medium, the reactor parts that come into contact with the culture medium being entirely or partially produced from silicone materials. The invention is characterized in that the silicone materials are produced from addition-crosslinked silicones, and the surface of the silicone materials has a contact angle to the water of at least 100°.
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TECHNICAL FIELD
[0001] The present invention relates to a sealing device for a door or a window, to a fastening means of such a drop-down seal and to an insert element of such a fastening means.
PRIOR ART
[0002] Manually or automatically actuable drop-down seals for doors or windows are usually arranged in a groove of a door leaf or window casement, or on an end side, and screwed on by way of an angled fastening bracket. This is disclosed, for example, in EP 1 122 394. U.S. Pat. No. 2,066,188 discloses a drop-down seal with a fastening plate.
[0003] Furthermore, EP 1 772 586 discloses an angled fastening bracket which is intended to improve mechanical fitting. Said angled fastening bracket is arranged in captive fashion in the housing rail.
[0004] EP 1 748 142 discloses an angled retaining bracket with a magnet arranged behind it, wherein a fastening screw passes through both the angled retaining bracket and the magnet.
[0005] EP 2 305 938 discloses a retaining element with a countersinkable screw.
DESCRIPTION OF THE INVENTION
[0006] It is an object of the invention to provide a sealing device, in particular a drop-down seal, which is straightforward to fit, in particular even by hand.
[0007] The sealing device according to the invention for a door or window has a housing rail and a sealing strip, which is retained in the housing rail. The sealing device also has at least one fastening means for fastening the housing rail on a door leaf or window casement, wherein the fastening means comprises a plate for resting on an end surface of the door leaf or window casement and also comprises a through-opening for a screw, said through-opening being arranged in the plate. According to the invention, a restraining means for retaining the screw is present in the through-opening.
[0008] This makes it possible for the screw to be pre-fitted. Use can be made, for this purpose, of commercially available screws, in particular wood screws. The operation of fitting the seal on the door leaf or window casement is simplified since it is no longer necessary for the screw to be held by hand. The fitter can use one hand to hold the (cordless) screwdriver and use the other hand to hold the seal, and possibly also the fastening means. This therefore makes it possible for the seal to be fitted, and fastened, in the door leaf using one hand.
[0009] Doors in this text are also understood to cover a gate, in particular a sliding gate. The seal is preferably a drop-down seal with a sealing strip which can be raised and lowered relative to the housing rail. However, it may also be, for example, a slide seal.
[0010] The restraining means preferably has at least one arm or is formed by at least one arm, which retains the screw. Said arm is arranged in the through-opening. This design is relatively cost-effective.
[0011] It is preferable for at least three, more preferably precisely three, arms to be present, said arms being arranged in the through-opening in a manner distributed over the circumference of the same. They are directed preferably radially toward a center point of the through-opening. The screw can thus be retained in an already pre-centered manner in the through-hole and incorrect orientation in the radial direction during fitting is not really possible any longer.
[0012] In other embodiments, precisely four arms are present. This is advantageous, in particular, when the restraining means, in particular the arms with restraining fingers, are to engage in the thread turns in an offset manner along the length of the screw. The screw can thus be retained without wobbling. As an alternative, or in addition, it can be retained in a state in which it is already oriented in the manner necessary for definitive fitting. This orientation runs usually parallel to the longitudinal direction of the housing rail.
[0013] The at least one arm preferably runs in a plane defined by the through-opening.
[0014] The at least one arm is preferably of bendable design such that it can be bent out of the through-opening when the screw is being screwed in. The screw can thus be countersunk in alignment with the surface of the plate in the door leaf or window casement. In addition, the at least one arm does not break off, and it is therefore also the case that it is not possible for any problematic small parts to remain in the seal or to scratch, or damage in any other way, any floor coverings such as parquet.
[0015] In one embodiment, the screw is retained in the through-opening at right angles to the plate. In another embodiment, the screw is retained at an angle other than 90° in relation to the plate. This can be achieved by at least one arm having a bent restraining finger.
[0016] In a straightforward embodiment, the restraining means is produced together in one piece with the plate and preferably in one piece with the fastening means as a whole. The fastening means is preferably a work piece punched from a metal, for example steel, a plastics injection molding or a zinc die casting. If the restraining means is formed in one piece with the plate, or even in one piece with the fastening means as a whole, then it consists preferably of the same material as the plate, in particular of metal or plastics material.
[0017] In other embodiments, the fastening means is produced from a first material, preferably from metal, and the restraining means is produced from a second material, preferably from a plastics material. The restraining means made of plastics material, in one embodiment, is applied to the plate or the fastening means by injection molding.
[0018] In another embodiment, the restraining means is an insert element which can be fixed in the through-opening. The restraining means is produced preferably from plastics material or metal. The fastening means, in this exemplary embodiment, is produced preferably from a metal, in particular steel. In this embodiment, it is possible for the insert element to be applied to the screw by injection molding or to be produced in the form of a separate component.
[0019] In preferred embodiments, the screw is retained in a fixed state by means of a droplet of adhesive. This is an extremely straightforward and cost-effective fixing method, in particular when the restraining means is formed in one piece with the plate and/or when the restraining means and the plate are produced from metal.
[0020] In a preferred embodiment, the entire angled retaining bracket is produced from plastics material, the bracket having the restraining means in its accommodating opening. It is possible for the restraining means to be formed in one piece with the rest of the angled retaining bracket or to be designed in the form of an insert element. The restraining means may be formed, for example, by the aforementioned at least one arm, preferably by three or four arms.
[0021] In another embodiment, the angled retaining bracket made of plastics material has a retaining ring, which encloses the screw and thus forms the restraining means. The retaining ring, or even the angled retaining bracket as a whole, can be applied to the screw by injection molding or produced in the form of a separate component. The angled retaining bracket may be formed in more than one piece, e.g. the retaining ring may be designed in the form of an insert element. It is preferably the case, however, that said angled retaining bracket is also formed in one piece.
[0022] If the fastening means, restraining means and screw are present in the form of three separate parts, then it is the case during fitting, depending on the embodiment, that the fastening means and restraining means first of all form a unit, into which the screw is fitted, or the restraining means is fastened first of all onto the screw, before the two are introduced together into the through-opening of the fastening means.
[0023] In preferred embodiments, the housing rail has a u-shaped cross section with two side walls and an upper crosspiece, which connects the two side walls to one another. The plate of the fastening means runs preferably at an angle of 90° or greater in relation to the crosspiece. If the fastening means is an angled retaining bracket, then the plate is formed by one limb of the angled bracket and a second limb of the angled retaining bracket runs at an angle of 90° or greater in relation to the plate.
[0024] If the angle is greater than 90°, then this facilitates automatic or semiautomatic mechanical fitting of the seal in a door leaf or window casement. It is possible for the seal, with fastening means pre-fitted, to be pushed into the door groove more easily than in the case of an angle of precisely 90°. The plate is then bent into a right angle in relation to the crosspiece by virtue of the screw being screwed tightly in the end surface of the door leaf or window casement. The angle of greater than 90° has, in addition, the advantage that, with the screw pre-fitted, the second limb can already be pushed all the way into the housing rail and need no longer be displaced relative to the housing rail when the screw is being screwed into the door leaf.
[0025] In one embodiment, the fastening means is formed in one piece with the housing rail or is fixed, e.g. welded or adhesively bonded, thereto. It is also possible, however, for it to be designed in the form of a separate component.
[0026] In preferred embodiments, the fastening means is a separate angled retaining bracket with a first and a second limb, wherein the first limb forms the plate with the through-opening and the second limb can be pushed onto the housing rail beneath the crosspiece. As a result, the fastening means can easily be produced separately from the seal. In addition, there are no further elements necessary for connecting the seal to the fastening element. The seal is preferably provided with such a fastening means at its two ends. However, arrangement of said fastening means at one end, and of an alternative retaining means at the other end, of the seal is also possible.
[0027] The second limb is preferably of such a length that it projects beyond the free end of the pre-fitted screw, and therefore the angled retaining bracket pushed into the housing rail is retained in the latter. This makes it easier for the angled retaining bracket to be fastened on the door leaf using one hand, and therefore facilitates the fitting of the seal.
[0028] At least one restraining element is preferably present on the second limb, said restraining element acting as a brake to prevent the angled retaining bracket from falling out of the housing rail. The restraining element may be a resilient tongue, an elevation and/or depression and/or a widened portion of the second limb or an alternative means. The restraining element preferably acts merely as a brake, and therefore the angled retaining bracket, even in the case of the housing rail running in the vertical direction, i.e. in the case of “overhead fitting”, does not fall out of the rail, although it is still the case that it can be pulled out of the rail without any greater amount of force having to be applied by hand. Said brake preferably forms merely a force fit with the housing rail. In alternative embodiments, however, the restraining means is designed such that the angled retaining bracket is retained in the housing rail and can be removed again only with the use of a tool or by a relatively large amount of force being applied by hand. In this case, the restraining means preferably forms a force fit and form fit with the housing rail.
[0029] In one embodiment according to the invention, the fastening means is an angled retaining bracket with a first and a second limb, wherein the first limb forms a plate for resting on an end surface of a door leaf or window casement and has a through-opening for a screw, wherein the restraining means for retaining the screw is present in the through-opening. The restraining means preferably has at least one arm, which is arranged in the through-opening.
[0030] In one embodiment according to the invention, the insert element has an annular main body with a hole, wherein the hole forms the through-opening for the screw, and wherein at least one arm is arranged in said hole for the purpose of retaining the screw.
[0031] The aforementioned embodiments can be combined with one another. Further embodiments are specified in the dependent claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Preferred embodiments of the invention will be described hereinbelow with reference to the drawings, which serve merely for explanatory purposes and should not be interpreted as being restrictive. In the drawings:
[0033] FIG. 1 shows a perspective illustration of a door leaf with a drop-down seal fitted;
[0034] FIG. 2 shows a perspective illustration of a first embodiment of an angled retaining bracket according to the invention;
[0035] FIG. 3 shows a view of the angled retaining bracket according to FIG. 2 as seen from the front;
[0036] FIG. 4 shows a side view of the angled retaining bracket according to FIG. 2 ;
[0037] FIG. 5 shows a perspective view of the angled retaining bracket according to FIG. 2 with a screw pre-fitted;
[0038] FIG. 6 shows a perspective view of the angled retaining bracket according to FIG. 2 with a screw fitted in a door leaf, the door leaf not being illustrated;
[0039] FIG. 7 shows a further perspective view of the angled retaining bracket according to FIG. 2 with a screw fitted in a door leaf, the door leaf not being illustrated;
[0040] FIG. 8 shows a side view of the angled retaining bracket according to FIG. 2 with a screw pre-fitted;
[0041] FIG. 9 shows a side view of the angled retaining bracket according to FIG. 2 with a screw fitted in a door leaf, the door leaf not being illustrated;
[0042] FIG. 10 shows a perspective illustration of the door leaf with drop-down seal according to FIG. 1 , with the angled retaining bracket pre-fitted;
[0043] FIG. 11 shows a longitudinal section through the door leaf according to FIG. 1 with the angled retaining bracket pre-fitted;
[0044] FIG. 12 shows a longitudinal section through the door leaf according to FIG. 1 with the angled retaining bracket fitted;
[0045] FIG. 13 shows a perspective illustration of a second embodiment according to the invention of an angled retaining bracket according to the invention with a screw pre-fitted;
[0046] FIG. 14 shows a front view of the angled retaining bracket according to FIG. 13 ;
[0047] FIG. 15 shows a side view of the angled retaining bracket according to FIG. 13 ;
[0048] FIG. 16 shows a longitudinal section through an enlarged detail according to FIG. 15 ;
[0049] FIG. 17 shows a perspective illustration of the angled retaining bracket according to FIG. 13 in the fitted state, although the door leaf and the seal are not illustrated;
[0050] FIG. 18 shows a side view of the angled retaining bracket according to FIG. 17 in the fitted state;
[0051] FIG. 19 shows a perspective illustration of the door leaf with drop-down seal with an angled retaining bracket according to FIG. 13 pre-fitted;
[0052] FIG. 20 shows a longitudinal section through the door leaf with drop-down seal and angled retaining bracket according to FIG. 19 ;
[0053] FIG. 21 shows the longitudinal section according to FIG. 20 in the fitted state;
[0054] FIG. 22 shows a perspective illustration of a third embodiment according to the invention of an angled retaining bracket according to the invention with a screw pre-fitted;
[0055] FIG. 23 shows a front view of the angled retaining bracket according to FIG. 22 ;
[0056] FIG. 24 shows a side view of the angled retaining bracket according to FIG. 22 in the pre-fitted state;
[0057] FIG. 25 shows a side view of the angled retaining bracket according to FIG. 22 following a removal operation;
[0058] FIG. 26 shows a perspective illustration of a fourth embodiment according to the invention of an angled retaining bracket with insert element according to the invention with a screw pre-fitted;
[0059] FIG. 27 shows a front view of the angled retaining bracket according to FIG. 26 ;
[0060] FIG. 28 shows a perspective illustration of the insert element according to FIG. 26 ;
[0061] FIG. 29 shows a longitudinal section through the angled retaining bracket according to FIG. 26 ;
[0062] FIG. 30 shows a side view of the angled retaining bracket according to FIG. 26 ;
[0063] FIG. 31 shows a perspective illustration of a fifth embodiment according to the invention of an angled retaining bracket according to the invention;
[0064] FIG. 32 shows a plan view of the angled retaining bracket according to FIG. 31 ;
[0065] FIG. 33 shows a front view of the angled retaining bracket according to FIG. 31 introduced into a housing rail of a drop-down seal;
[0066] FIG. 34 shows a cross section through the arrangement according to FIG. 33 ;
[0067] FIG. 35 shows a plan view of a sixth embodiment of an angled retaining bracket according to the invention;
[0068] FIG. 36 shows a side view of the angled retaining bracket according to FIG. 35 ;
[0069] FIG. 37 shows a front view of the angled retaining bracket according to FIG. 35 introduced into a housing rail of a drop-down seal;
[0070] FIG. 38 shows a cross section through the arrangement according to FIG. 35 ;
[0071] FIG. 39 shows a perspective view of a seventh embodiment of an angled retaining bracket according to the invention;
[0072] FIG. 40 shows a further perspective view of the angled retaining bracket according to FIG. 39 ;
[0073] FIG. 41 shows a front view of the angled retaining bracket according to FIG. 39 ;
[0074] FIG. 42 shows a longitudinal section through the angled retaining bracket according to FIG. 39 ;
[0075] FIG. 43 shows a perspective view of an eighth embodiment of an angled retaining bracket according to the invention;
[0076] FIG. 44 shows the perspective view of the angled retaining bracket according to FIG. 43 with a screw pre-fitted;
[0077] FIG. 45 shows a further perspective view of the angled retaining bracket according to FIG. 43 with a screw pre-fitted;
[0078] FIG. 46 shows a longitudinal section through part of the angled retaining bracket according to FIG. 43 with a screw pre-fitted;
[0079] FIG. 47 shows a front view of a ninth embodiment of an angled retaining bracket according to the invention;
[0080] FIG. 48 shows a perspective view of the angled retaining bracket according to FIG. 47 ;
[0081] FIG. 49 shows the perspective view of the angled retaining bracket according to FIG. 47 with a screw pre-fitted and a droplet of adhesive;
[0082] FIG. 50 shows a longitudinal section through the angled retaining bracket according to FIG. 47 ;
[0083] FIG. 51 shows a front view of a tenth embodiment of an angled retaining element according to the invention;
[0084] FIG. 52 shows a perspective view of the angled retaining bracket according to FIG. 51 ;
[0085] FIG. 53 shows the perspective view of the angled retaining bracket according to FIG. 51 with a screw pre-fitted; and
[0086] FIG. 54 shows a longitudinal section through the angled retaining bracket according to FIG. 51 .
DESCRIPTION OF PREFERRED EMBODIMENTS
[0087] FIG. 1 shows a door leaf T with a groove in its lower end side. A drop-down seal 3 of a known type is incorporated in said groove and is fastened on the lateral end surface of the door, via an angled fastening bracket 1 , using a screw 2 .
[0088] The drop-down seal 3 illustrated here has a u-shaped housing rail 30 , which is open in the downward direction and in which is arranged a sealing strip, i.e. a carrier strip 31 with a sealing element 32 . The carrier strip 31 can be raised and lowered relative to the housing rail 30 , a mechanism which cannot be seen in the figures being present in the housing rail 30 for this purpose. In the lowered state, the sealing element 32 provides sealing in relation to a floor B.
[0089] The triggering of the seal and thus the raising and lowering operations take place usually via an actuating rod which projects from one end side of the seal and, when the door leaf is being closed, strikes against the door frame and is pushed in, the mechanism therefore being activated for lowering purposes. When the door leaf is being opened, the actuating rod is relieved of loading and the sealing strip is raised again by way of restoring springs.
[0090] The seal can also be triggered in other ways, for example manually or by motor-driven or magnetic means. It is also possible for the seal to be a slide seal, which is therefore not lowered when the door is being closed. It is likewise possible for the sealing element 32 to be in a form other than that presented here.
[0091] FIGS. 2 to 12 show a first exemplary embodiment of the angled retaining bracket 1 according to the invention. The angled retaining bracket 1 has a first limb 10 for butting against the end side of the door leaf T and a second limb 11 , which can be pushed into a groove 33 (see FIG. 1 ) of the housing rail 30 . In order to facilitate introduction, the second limb 11 has an introduction means 100 in the form of an oblique edge at its free end. The first limb 10 forms a plate.
[0092] The angled retaining bracket 1 is produced preferably from a metal, in particular steel. It is formed in one piece. The two limbs 10 , 11 are of preferably planar design.
[0093] The first limb 10 has a through-opening 12 for the screw 2 . It is also possible for more than one such opening to be present, in which case preferably all the openings are designed according to the invention as described hereinbelow.
[0094] The through-opening 12 has an encircling countersink 13 in the form of an oblique surface in which a screw head can be countersunk. Also present in the through-opening 12 are three arms 14 , which project radially inward toward the center point of the opening 12 . These arms are nevertheless preferably shorter than the radius, and they therefore do not extend as far as the center point. It is also possible for fewer or more than these three arms 14 to be present. The arms 14 are aligned preferably with the rear side of the first limb 10 . The rear side is directed toward the free end of the second limb 11 and/or, in the fitted state, toward the lateral end surface of the door leaf T. The arms 14 have their opposite surfaces aligned preferably with the base of the encircling countersink 13 , the base being adjacent to said rear side. The arms 14 are preferably designed to have thinner walls than the first limb 10 . As a result, or on account of some other configuration, they are preferably bendable. The bending capability can be increased, in addition, by recesses 15 in the circumference of the through-opening 12 , said recesses being adjacent to the arms 14 . In this example, the arms 14 are produced from the same material as the rest of the angled retaining bracket 1 and form, as restraining means, part of the single-piece angled retaining bracket 1 .
[0095] In FIGS. 5 and 8 , the screw 2 has its shank 20 passing through the opening 12 of the angled retaining bracket and is retained in said position by virtue of the arms 14 . The screw shank 20 here extends more or less, or preferably precisely, perpendicularly to the plate, i.e. to the first limb 10 . In figures FIGS. 6, 7 and 9 , the screw 2 has been screwed all the way into the door leaf, the door leaf T itself not being illustrated. The screw head 2 is aligned with the outer surface of the first limb 10 . The arms 14 are bent inward or toward the rear side and butt preferably an encircling oblique surface of the screw head 21 . The arms 14 are preferably pushed into the wood of the door leaf T. In this example, the screw 2 is longer than the second limb.
[0096] FIG. 10 illustrates the seal in the pre-fitted state. The seal is already located in the door groove and is already provided with the angled element 1 . The screw 2 is retained in the angled element 1 and cannot fall out. However, it has not yet been screwed in.
[0097] As can be seen in FIG. 11 , the screw 2 is guided through the angled retaining bracket 1 and is retained in a position perpendicular to the end surface of the door leaf. It can then be screwed in with one hand until the angled retaining bracket 1 butts against the end surface of the door leaf and the seal is fixed in the door. This illustrated in FIG. 12 .
[0098] Yet more exemplary embodiments will be explained hereinbelow. What has been said above, in particular the variants specified above, also applies to these exemplary embodiments.
[0099] FIGS. 13 to 21 illustrate a second exemplary embodiment of an angled retaining bracket according to the invention. In this case, the first and second limbs 10 , 11 do not, as in the first example, form a right angle. Rather, the angle is greater than 90°.
[0100] The screw 2 , however, is nevertheless retained preferably parallel to the second limb 11 and cannot fall out, as can be seen to good effect in FIGS. 15 and 20 . For this purpose, at least one arm 14 , preferably the arm or arms 14 located in the upper half of the through-opening 12 , is of angled design. It has, for example, a restraining finger 140 . This restraining finger 140 runs at an angle to the rest of the arm 14 and forms the free end of the arm 14 . The arms 14 located in the lower half of the opening 12 preferably have no such restraining finger 140 ; rather, as in the first example, they are of rectilinear design. As illustrated in FIG. 16 , they project, preferably at an angle, beyond the rear side of the first limb 10 .
[0101] By virtue of this right-angled arrangement of the screw 2 , the angled retaining bracket, once again, can be pre-fitted in the seal such that it cannot fall out, and it can be screwed on the door leaf with one hand. There is no need for the angled retaining bracket 1 , when the screw is being screwed in, to be held additionally by hand. Also, there is no need for the screw 2 to be positioned at an angle.
[0102] This embodiment has, in addition, the advantage that the second limb 11 can be pushed all the way into the housing rail 3 as early as the pre-fitting state and there is therefore no longer any need for the angled retaining bracket 1 to be displaced relative to the housing rail 3 when being screw-fitted on the door leaf.
[0103] For the screwing-in operation, the first limb 10 bends toward the end surface of the door or toward the second limb 11 , until the two limbs 10 , 11 form a right angle. This is illustrated in FIGS. 17, 18 and 21 .
[0104] FIGS. 22 to 25 show a further exemplary embodiment. The screw has a narrowing 22 between the shank 20 and head 21 . It is therefore a known type of captive screw.
[0105] As illustrated in FIGS. 22 and 24 , it is pre-fitted in the same position as the screws described above. If the retaining bracket 1 is removed from the door leaf T, and the retaining bracket 1 is pulled out of the housing rail 3 , then the screw 2 remains in the angled retaining bracket 1 , as can be seen in FIG. 25 .
[0106] In the exemplary embodiments described up until now, the arms 14 formed a restraining means which is in one piece with the rest of the angled retaining bracket 1 . In the exemplary embodiment according to FIGS. 26 to 30 , the restraining means is an insert element 4 , which is retained in the opening 12 . It is retained preferably in captive fashion therein. Said insert element 4 can be seen to good effect in FIG. 28 . It has a circular main body 41 with an encircling flange 40 and a through-opening 44 . The main body 41 forms on its inner side, i.e. as a circumference of the opening 44 , a beveled surface or an encircling countersink 410 in the form of an oblique surface for accommodating the screw head 21 . Arms 43 , directed once again radially forward the center point, are present at the end of said countersink 410 and retain the screw 2 in its pre-fitted position such that it cannot fall out. As can be seen in FIG. 28 , the free ends of the arms 43 are preferably rounded and preferably set in adaptation to the circumference or thread of the screw shank 20 . The same also applies to the other embodiments described above.
[0107] On its outer circumference the insert element 4 has restraining noses 42 , which are distributed preferably over the circumference and project radially outward. They serve to retain the insert element 4 in the opening 12 of the first limb 10 . The restraining noses 42 are designed preferably in the form of latch-in elements, as can be seen to good effect in FIG. 29 .
[0108] The insert element 4 is produced preferably from plastics material or from metal. Either it is connected to the screw prior to the screw and angled retaining bracket being joined together or it is already retained in the angle retaining bracket, in particular fitted therein. It is produced from plastics material, but may also be applied directly to the screw 2 or the angled retaining bracket 1 by injection molding.
[0109] FIGS. 31 to 38 illustrate two variants of angled retaining brackets 1 according to the invention. These variants may be combined as desired with the exemplary embodiments above. In the embodiment according to FIGS. 31 to 34 , the second limb 11 has, on either side, a convexity or widened portion 101 in the direction perpendicular to the first limb 10 . A longitudinal slot 102 runs along the periphery in each case in the region of said widened portion 101 . The longitudinal slot 102 is preferably curved. The second limb thus forms a brake to prevent the angled retaining bracket 1 from falling out of the housing rail 3 . When the second limb 11 is being introduced into the groove 33 of the housing rail 3 (see FIG. 33 ), the second limb 11 is compressed in this region and the angled retaining bracket 1 is thus retained in the housing rail 3 , albeit without already being fixed firmly thereto. This is illustrated in FIG. 34 . However, it is preferably still the case that the angled retaining bracket 1 can be removed by hand without any great amount of force having to be applied. Depending on the embodiment of the restraining element, however, it is also possible for the application of relatively large forces, or a tool, to be necessary in order to separate the angled retaining bracket again from the housing rail.
[0110] In the embodiment according to FIGS. 35 to 38 , the second limb 11 is provided with a bend in one region. This is preferably a longitudinal bend located preferably in the central region of the limb 11 . The limb 11 thus has an elevation 103 and a depression 104 . This also results in clamping forces taking effect following introduction into the groove 33 , and in the angled retaining bracket 1 thus being retained in the housing rail 3 such that it cannot fall out. This can be seen in FIG. 38 .
[0111] FIGS. 39 to 42 illustrate a further exemplary embodiment. Also present, once again, are arms 14 , which are formed preferably in one piece with the first limb 10 .
[0112] In this embodiment, the arms 14 or lugs are designed to be wider than in the variants described up until now. In this example, each arm is of semi-elliptical or semicircular shape. At their free ends, they form a common, more or less closed circumference of an opening 12 , in which the screw 2 is accommodated. It is preferably the case, however, that the arms 14 do not come into contact at these free ends.
[0113] The free ends have angled restraining fingers 140 . Two of these extend onto that side of the angled retaining bracket 1 which is directed toward the second limb 11 . The other two restraining fingers 140 are bent onto that side of the angled retaining bracket 1 which is directed away from the second limb 11 . It is preferable for in each case two adjacent restraining fingers 140 to be oriented in the same direction.
[0114] Each restraining finger 140 preferably forms more or less a right angle with the rest of the arm 14 . Each arm 14 runs preferably more or less parallel to the first limb 10 . It is preferably the case that that, with the exception of the direction of their restraining fingers 140 , all of the arms 14 are identical in terms of shape and orientation. The arms 14 are distributed preferably uniformly over the inner circumference of the countersink 13 . It is preferably the case that precisely four arms 14 are present, each of these having a restraining finger 140 . The restraining fingers 140 here engage in the screw threads 23 preferably in an offset manner over the course of said screw thread.
[0115] It has been found that said arrangement fixes the screw 2 to better effect and the latter wobbles to a lesser extent in its pre-fitted position. In addition, the screw 2 can be retained automatically in a horizontal position, i.e. parallel to the second limb 11 , even in the pre-fitted position, and there is therefore no longer any need for it to be oriented in position prior to being fitted definitively in the door.
[0116] FIGS. 43 to 46 likewise illustrate an embodiment in which the screw 2 is retained in optimal fashion in its pre-fitted position.
[0117] In this exemplary embodiment, the arms 14 , 14 ′, 14 ″, 14 ′″ are bent such that they have their restraining fingers 140 engaging in the screw thread 23 in an offset manner over the course of said screw thread. The arms 14 , 14 ′, 14 ″, 14 ′″ are, accordingly, bent differently. Their restraining fingers 140 all extend in the same direction, i.e. to the side which is directed toward the second limb 11 .
[0118] The first arm 14 is of more or less right-angled design, part of the arm 14 being formed by the restraining finger 140 . The adjacent, second arm 14 ′ is of identical design or forms a second angle, which forms an oblique surface between the restraining finger 140 and the opposite end of the arm 14 ′. Said oblique surface here is inclined such that the restraining finger 140 of said second arm 14 ′ projects further beyond the first limb 10 than the first restraining finger 140 of the first arm 14 . It is also the case that the third arm 14 ″ and the fourth arm 14 ′″ have oblique surfaces which are directed such that the corresponding restraining fingers 140 each project to an even greater extent. This means that they follow the thread 23 of the screw 2 , as can be seen to good effect in FIGS. 44 and 46 .
[0119] The oblique surfaces may all be directed inward, that is to say to the side which is directed toward the second limb 11 . It is also possible, however, for one or more oblique surfaces to be inclined outward, that is to say to that side of the first limb 10 which is located opposite the second limb 11 .
[0120] FIGS. 47 to 50 illustrate a further embodiment in which wobbling of the pre-fitted screw 2 is prevented and/or, even in the pre-fitted state, the screw 2 is arranged in a fixed state in a position parallel to the second limb 11 , said position being required for fitting purposes.
[0121] It is also the case in this example that the fingers 14 are of preferably planar design, wherein, once again, they are preferably of semi-elliptical or semi-circular shape. The restraining fingers 140 are present or absent, depending on the embodiment. There are no restraining fingers illustrated in the present figures. The screw 2 is retained in a fixed position the through-opening 12 of the first limb 10 by way of the droplet 5 of adhesive. When the screw 2 is being screwed in, its bond with the droplet 5 of adhesive is released by the screw thread and the screw 2 can be displaced relative to the angled retaining bracket 1 .
[0122] FIGS. 51 to 54 illustrate a further exemplary embodiment. The latter has the advantage that it is straightforward and cost-effective to produce and nevertheless allows for the screw to be retained in optimal fashion in the pre-fitted state, wherein, in its pre-fitted state, the screw is already oriented correctly for definitive fitting purposes. This is achieved here by the angled retaining bracket 1 as a whole, including the restraining means, being produced from plastics material. It can thus be applied to the screw 2 by injection molding. In the embodiment illustrated here, the angled bracket 1 , once again, has the first and second limbs 10 , 11 , which preferably form a right angle. A retaining ring 141 is arranged centrally in the through-opening of the first limb 10 and is connected to the first limb 10 by a crosspiece 142 . In this case there are three crosspieces 142 present, these being distributed uniformly over the circumference. The retaining ring 141 has an accommodating through-opening 143 , through which the screw 2 passes. The retaining ring 141 thus forms the retaining means for the screw 2 in its pre-fitted state.
[0123] The crosspieces 142 preferably have predetermined breaking points or are designed to be thin or weak enough to break when the screw 2 is being screwed in during the fitting operation of the seal, it thus being possible for the screw 2 to be screwed definitively into the door.
[0124] The first limb 10 is preferably of sufficiently thick design for the angled retaining bracket 1 , even when configured from plastics material, to be sufficiently stable to retain the drop-down seal in the door. As can be seen in the figures, said first limb is preferably thicker than the second limb 11 .
[0125] In one embodiment, the angled retaining bracket 1 made of plastics material is produced in the form of a discrete single-piece element and is connected to the screw at a later stage, for example welded, adhesively bonded or connected by a press fit at a later stage.
[0126] It is preferable, however, for the angled retaining bracket 1 to be applied to the screw 2 by injection molding, the retaining ring 141 therefore being produced by virtue of the screw 2 being overmolded.
[0127] All the above described embodiments of the angled retaining bracket with restraining means formed thereon in one piece can be produced from metal or plastics material. If they are produced from plastics material, they can be made in the form of discrete elements and connected to the screw at a later stage. It is also possible, however, for them to be applied in this form to the screw, in particular a metal screw, by injection molding.
[0128] In the drawings mentioned, some of the screws are illustrated without threads. This has been done merely in order to simplify the illustration. Each of the screws has a thread.
[0129] The individual features of the embodiments mentioned above can be combined with one another in addition to form yet more embodiments.
[0130] The sealing device according to the invention and the angled retaining bracket according to the invention allow the angled retaining bracket to be fitted on the door leaf using one hand and thus facilitate the fitting of the seal.
LIST OF REFERENCE SIGNS
[0000]
1 Angled fastening bracket
10 First limb
100 Introduction means
101 Convexity
102 Longitudinal slot
103 Elevation
104 Depression
11 Second limb
12 Through-opening
13 Countersink
14 Arm
14 ′ Second arm
14 ″ Third arm
14 ′″ Fourth arm
140 Restraining finger
141 Retaining ring
142 Crosspiece
143 Accommodating opening
15 Recess
2 Screw
20 Screw shank
21 Screw head
22 Narrowing
23 Thread turn
3 Seal
30 Housing rail
31 Carrier rail
32 Sealing element
33 Groove
4 Insert element
40 Flange
41 Main body
410 Countersink
42 Restraining nose
43 Arm
44 Through-opening
5 Droplet of adhesive
T Door leaf
B Floor
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The invention relates to a seal device for a door or a window having a housing rail ( 30 ) and a sealing strip ( 31, 32 ) retained in the housing rail ( 30 ). The seal also has at least one fastener ( 1 ) for fastening the housing rail ( 30 ) to a door leaf or window sash (T) of the door or window, wherein the fastener ( 1 ) comprises a plate ( 10 ) for lying on an end face of the door leaf or window sash (T) and a passage opening ( 12 ) for a screw ( 2 ), which passage opening is arranged in the plate ( 10 ). A retaining element ( 14, 43 ) for retaining, the screw ( 2 ) is present in the passage opening ( 12 ). Said seal device enables one-handed mounting of the retaining bracket on the door leaf and thus makes the mounting of the seal easier.
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BACKGROUND OF THE INVENTION
The domestic automatic dishwasher is generally of the type having a washing chamber with open-framework racks therein for holding dishes to be washed and means for recirculating washing liquid accumulated in the lower end of the washing chamber upwardly over the dishes to loosen and carry away food soil therefrom. An inherent problem in such a machine is that food soil particles are suspended in the recirculating flow of washing liquid and that redeposition of these particles on the clean dishes can occur during the cleaning process. During the recirculation of the washing liquid large food particles flushed from the dishes will be carried downwardly and broken up into particularly small particles that are then washed back on to the dishes. These small particles adhere to the cleaned items and often defy removal during subsequent rinsing steps in the operation of the machine.
An approach to correcting this problem has been to provide a means to remove food particles from the recirculating flow so that the washing liquid moving downwardly in the washing chamber carries food soil with it but the same washing liquid redistributed upwardly in the washing chamber is relatively free of these soil particles. To accomplish this a filtering medium in the form of a screen has been interposed in the path of the liquid recirculation whereby soil particles are prevented from further passage while washing liquid is free to move therethrough and be recirculated in the machine's washing chamber. The use of a filtering screen introduces its own problem; that of the need for cleaning the collected soil from the screen either between each use of the dishwasher or between wash and rinse steps of the operational cycle so that the screen does not become clogged and thereafter prevent passage of liquid therethrough.
One approach to the filter-cleaning problem has been to provide a removable filter that the machine operator can take out of the machine, rinse in the sink, and then reinstall in the machine for further use. Another and more popular approach has been the provision of a self-cleaning filter wherein the filter is flushed by a reversed flow or an automatic filter rinsing step provided in the operational cycle of the machine. A notable example of a dishwashing machine having a self-cleaning filtering arrangement is disclosed in U.S. Pat. No. 2,629,391 issued to F. S. Hummel on Feb. 24, 1953. Hummel teaches the provision of a filtering screen disposed over the sump in the bottom of a dishwashing machine's wash chamber. He also teaches the use of a specific liquid injection step to flush soil from the filter and also to wash collected soil from the sump and outwardly through a gravity drain line.
More recent examples of self-cleaning filter arrangements in dishwashers will be found in U.S. Pat. No. 3,090,391 issued to H. J. Kaldenberg et al. on May 21, 1963 and U.S. Pat. No. 3,575,185 issued to D. J. Barbulesco on Apr. 20, 1971. The Kaldenberg et al. and Barbulesco patents relate to dishwashing machines utilizing an annular sump arrangement provided circumjacent the axial flow pumping mechanism in a dishwasher and having an annular screen filter arrangement disposed in close proximity to the sump. Each of these patents teaches a different structure for a means for slinging liquid outwardly toward the annular filter whereby a backwash is accomplished to remove soil particles therefrom.
Commonly assigned U.S. Pat. No. 3,807,419, issued to the inventors hereof and dated Apr. 30, 1974, teaches the combination of a self-cleaning filter arrangement with a soil receptacle disposed at a position remote from the wash chamber's sump. Drainage means specifically provide for draining particles from the receptacle during the drain cycle. This type of filtering system is referred to as a "bypass" or "partial-flow" system since only a portion of the washing liquid is filtered at any given time. At present washing volumes and pump rates, the total volume of liquid is recirculated through the spraying system approximately 20 times per minute. Therefore, it is reasonable to conclude that all of the liquid eventually passes through the "bypass" filter. Of course, one of the primary advantages of this system, in addition to not requiring manual filter cleaning, is that the dishwasher will continue to operate even if the filter becomes completely clogged. The filter is cleaned or backflushed by the downwardly cascading washing liquid which impinges against the downstream-side of the filter screen. The soil-collecting receptacle is placed adjacent the back wall of the washing chamber and receives for the most part, recirculating liquid which falls downwardly along the back wall. Reliance on the downwardly cascading liquid along the back wall to supply liquid to the receptacle may not be entirely satisfactory for every dishwasher design or recirculation system.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide supplemental liquid collecting means for supplying liquid to the soil-removal receptacle which would not normally fall or flow into the receptacle.
The present invention may be broadly summarized as relating to an automatic dishwashing machine of the type having a washing chamber and means therewith for providing washing liquid in the washing chamber and accumulating it at a relatively low level therein. The washing machine includes spray means for circulating the flow of washing liquid generally throughout the washing chamber, and a drainage sump is provided in the bottom wall of the chamber for supplying liquid to the spray means and for conducting soil-laden washing liquid or effluent out of the machine. A soil-collecting receptacle is provided in the wash chamber along the back wall thereof having an open portion disposed above the normal level of accumulated liquid in the chamber and in the path of a portion of the liquid recirculated within the chamber. Adjacent the soil-collecting receptacle is a fine-mesh screen filter disposed across the flow of liquid recirculation and adapted to pass liquid therethrough while blocking the passage of food soil particles. Two troughs are provided along the chambers side walls and disposed above the open portion of the soil-collecting receptacle. The troughs collect liquid falling downwardly along the side walls and carry the liquid to the receptacle for filtering. Means for draining the collected soil particles from the receptacle is also provided.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational cut-away view of the bottom portion of a domestic dishwashing machine in accordance with the present invention.
FIG. 2 is a fragmentary sectional view taken along lines 2--2 of FIG. 1.
FIG. 3 is a fragmentary plan view taken along lines 3--3 of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 there is illustrated the lower portion of an automatic dishwashing machine 10 including a cabinet 11 defining therein a washing chamber 12. Access to the washing chamber 12 is obtained by opening a door 13 pivoted at its lower end and located on the front side of the cabinet 11. A dish rack 14 is shown supported for slidable movement within the washing chamber 12 so that it may be selectively slid outwardly through the cabinet's front access opening to facilitate loading and unloading of the items to be washed in the machine 10. The lower end of the washing chamber 12 is defined by a bottom wall or floor portion 15 that separates it from a lower motor-pump compartment 16. Housed within the compartment 16 is a motor-pump assembly 17 including an electric motor 18 that drives a pump means 19 for recirculating washing liquid to and from the washing chamber 12 and for draining washing liquid from the washing chamber 12 outwardly to the household sewage system. The operational cycle of such a machine generally includes a number of washing and rinsing steps and a final drying step. In a dishwasher machine, such as that shown in FIG. 1, heated water from the household supply line is directed into the washing chamber 12 by valve means actuated by a timer control (not shown). The water accumulates to a predetermined level on the floor portion 15 and then the timer control of the machine causes the electric motor 18 to be energized to drive the pump 19 in a recirculation operation. This method of fill is called the "static" method. A dynamic fill is also used whereby the motor is energized and the pump goes into the recirculation mode during the time controlled fill period. In the recirculation operation the accumulated washing liquid is drained out of the washing chamber 12 by means of a sump 20 emptying into a conduit 21 leading to the pump 19. The liquid is then forced upwardly by the pump 19 through a conduit 22 leading to a hollow horizontally elongated spray arm 25 located within the lower portion of the washing chamber 12.
Generally, clean water is introduced into the machine for each wash step and again for each rinse step, and detergent is added, by automatic means (not shown), for the wash step. The term "washing liquid" is therefore used herein in a generic sense to refer broadly to any form of cleansing liquid utilized for recirculation within the dishwashing machine. The washing liquid is distributed from the spray arm 25 by means of orifices 26 spaced therealong. The spray arm 25 is reactively driven by having at least one of the orifices disposed to discharge a jet stream in a direction such that the spray arm reacts to the force of the discharge and rotates in a horizontal plane. A thorough and generally uniform distribution of washing liquid in the washing chamber 12 is thereby obtained. Recirculation of the washing liquid from the washing chamber 12, through the pump 19 and, thence through the spray arm 25, is continued for a predetermined length of time after which the electrical circuit to a drain valve means (not shown) causes the valve means to automatically switch an outlet within the pump means 19 so that recirculation ceases and the pump 19 begins to discharge the washing liquid from the washing chamber 12 outwardly through a drain hose 27 leading ultimately to the household sewage system.
Commonly assigned co-pending patent application (9D-DW-10516) teaches a self-cleaning filter arrangement utilizing the spray arm 25 to clean the filter 32 (described below).
Shown in FIG. 1 and more specifically in FIG. 3, is a soil-removal means 82 in the form of a receptacle 30 having a trough 31 disposed in the path of recirculation of liquid within the washing chamber 12 and adapted to fill and overflow with the recirculated liquid caught therein. The soil-removal means further includes the filtering means 32 contiguous to the trough 31 and disposed in the path of the liquid flow whereby liquid from the receptacle passes through the screen while soil particles carried in the washing liquid are blocked from passage and therefore halt against the back or upstream side of the screen. As shown in FIG. 3, the trough 31 may be transversely elongated to extend across the substantially entire back wall 34 of chamber 12. In addition to the trough 31, the receptacle 30 further comprises a lower end portion in the form of a tubular box or hopper 35. The trough 31 has a configuration such that liquid and soil particles collected therein will flow centrally downwardly through an opening (not shown) into the hopper 35. A bottom 33a of the trough 31 is sloped centrally downwardly, and a back wall portion 33b, as shown in FIG. 1, is sloped inwardly whereby motion of the liquid collected in the trough will cause soil particles to flow toward the central bottom opening. The side of the trough 31 facing toward the wash chamber 12 has an erect wall portion 33c that extends upwardly to the lower edge of the filtering screen 32. It should be noted that wall 33c of trough 31 is at least partially above the normal level of washing liquid accumulated on the bottom 15 of chamber 12. The filtering screen 32 is disposed at approximately a 45° angle with reference to the back wall 34 of the wash chamber 12, and the upper long edge of the filtering screen 32 abuts against the forward edge of a horizontally disposed perforated cover plate 37. The cover plate 37 is disposed across the trough's opening and is provided with a uniform arrangement of apertures 38 equidistantly spaced thereacross, as shown in FIG. 3. Successive longitudinally oriented slots 39 are also provided in the cover plate 37. The cover plate 37 may be said to partially enclose a first open top means 88 of receptacle 30 serving to collect recirculating liquid falling therein. Cover plate 37 also forms a second open top means 89 of receptacle 30 wherein the filter 32 is secured as described above.
For more detailed illustration and description of the soil-removing means 82 reference may be made to the above-mentioned commonly-assigned U.S. Pat. No. 3,807,419, and specifically FIGS. 2-4 thereof.
Referring to FIGS. 1 and 2, and more specifically to FIG. 2, the supplemental liquid collecting and conduit means 70 is shown. The conduit means 70 is shown as it would appear on the left side of chamber 12 looking front to back. It includes an open trough 71 having a vertical mounting section 71a for attachment to the interior of wall 11 of chamber 12, a bottom 71b extending inwardly and horizontally from wall 11 and a vertical side wall 71c sloped slightly inwardly as it rises from the bottom 71b. The trough 71 is attached to wall 11 by any suitable means such as welding, or may be formed as part of the side wall where the chamber 12 is formed from a polypropylene resin (as is presently known to those skilled in the art). Referring to FIG. 1, the trough is mounted above the soil-removal means 82 and is sloped downwardly toward the soil-removal means. The elongated trough 71 extends along substantially the entire width of the side wall 11 with its rearward terminal end 71d located over the open top section 88 of trough 31. During the recirculation of washing liquid within chamber 12, the liquid splashing against the side walls of the chamber cascades downwardly falling into the trough 71 wherein it flows down the trough 71 and on to the cover plate 37 of trough 31. Thus, liquid which would normally fall directly onto the bottom 15 of chamber 12 is collected and distributed to the soil-removal means 82 for filtering. This in turn causes the total volume of liquid used in any one cycle to be filtered a greater number of times per cycle resulting in cleaner recirculated washing liquid and more effective cleaning performance.
In the operation of the dishwasher 10 shown in FIG. 1, the washing step of the operational cycle commences with the introduction of water to the washing chamber 12 whereby water accumulates on the floor portion 15 to a maximum level below the under surface of the spray arm 25 and below the bottom-most portion of screen 32. Detergent is automatically added to the water and the resultant washing liquid is caused to follow a circular path down the sump 20 and through the conduit 21 to the pump 19. As heretofore described, motor 18 causes the pump 19 to force the washing liquid upwardly and outwardly through the hollow spray arm 25. The spray arm 25 rotates in response to a jet stream discharged from at least one end thereof and the orifices 26 discharge streams of washing liquid upwardly over items stored in the rack 14 and generally over additional items in one or more other vertically spaced racks (not shown). The cascade of washing liquid distributed through the washing chamber 12 tends to progress downwardly over the items in the rack but primarily down along the inside surface of the door 13, the side walls of the wash chamber 12 and the back wall 34. Therefore, the back wall 34 and the troughs 71 serve to direct recirculated washing liquid downwardly against the cover plate 37.
As the washing step (or rinsing step) progresses for its predetermined time, the soil-laden washing liquid flows downwardly repeatedly along the washing chamber back wall 34 and the troughs 71 toward the cover plate 37. The washing liquid moves through the slots 39 and the perforations 38 of the cover plate 37 and into the trough 31. Obviously, once the trough 31 is initially filled, it flows over its forward wall 33c and outwardly through the filtering screen 32. The filtering screen 32 is preferably of a fine mesh whereby even very small food soil particles will be blocked from passage therethrough and retained by the back side of the filtering screen 32. The filtering screen 32 is disposed whereby washing liquid moving down behind the rack 14 and forward of the back wall 34 will strike against the outside surface of the screen. The force of the downwardly cascading washing liquid impinges against the outside surface of the screen 32 serving to jar soil loose from the back side of the screen 32 whereby it will continuously move away from the screen as it collects thereagainst to keep the screen open for passage of washing liquid therethrough. As quantities of soil particles retained in the trough 31 by the screen 32 increase and agglomerate, they tend to precipitate and settle downwardly into the tubular hopper 35 so that by the end of the wash step of the machine's operational cycle a high percentage of suspended soil particles have thus been removed from the recirculated washing liquid in the wash chamber 12 and collected in the hopper 35. At the end of the washing step, the timer-control means (not shown) energizes the drain valve means for a period to permit final drainage of liquid from the cleaned items in the chamber 12. After the drain valve is automatically moved from the first to the second position the pump 19 continues to receive the washing liquid from the chamber 12 through the sump 20 and the conduit 21 and will pump it outwardly through the drain line 27 to the lower end of the hopper 35. The drainage flow or effluent is pumped through the hopper and outwardly through a final discharge line 44 draining outwardly from the dishwasher 10. The final discharge line 44 on a permanently installed dishwasher would lead directly to the household sewage system. On a portable type of dishwashing machine the final discharge line 44 would be provided with an outer end disposed to dispense the effluent liquid into the kitchen sink.
In order to accomplish effective drainage of hopper 35 various mechanisms may be employed. Two such devices are shown and described in the above-mentioned commonly-assigned U.S. Pat. No. 3,807,419, and specifically FIGS. 4 and 5 thereof.
It should be apparent to those skilled in the art that the embodiments described heretofore are considered to be the presently preferred forms of this invention. In accordance with the Patent Statutes, changes may be made in the disclosed mechanism in the manner in which it is used without actually departing from the true spirit and scope of this invention. For example, the disclosed supplemental collecting troughs could be formed as an extension or part of one of the dish racks, either at the sides of the rack or along the area therebetween. Such "rack troughs" would then collect recirculating liquid falling along the chamber side walls or that which falls or cascades downwardly without contacting the walls of the washing chamber. Many dish racks are suspended from inwardly projecting tracks formed or attached to the interior side walls; the troughs disclosed herein could also be formed as part of these tracks.
It should also be understood that this invention could be applied with equal success in a dishwasher having a spray system different from or in addition to the horizontally rotating spray arm 25; for example, dishwashers which utilize supplemental vertical spray towers or horizontally mounted spray tubes which are known in the art.
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An automatic dishwashing machine is provided with bypass soil-collecting and filter means disposed independent of the sump whereby food soil suspended in the recirculating washing liquid is filtered and collected in a receptacle during the washing/rinsing operation. It includes supplemental liquid collecting means disposed in a flow path separate and upstream of the soil-collecting means and operative to channel an additional quantity of recirculating washing liquid to the soil-collecting means. Drain means removes the washing liquid and the filtered food soil from the receptacle during the drain cycle.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 61/780,550, filed on 13 Mar. 2013. The entire disclosure of the above application is incorporated herein by reference.
FIELD
The present disclosure relates to a male threaded pipe fitting extraction device.
BACKGROUND
This section provides background information related to the present disclosure which is not necessarily prior art.
A male threaded pipe fitting may fracture within a counterpart female threaded pipe fitting. In such a situation, removal of the male threaded pipe fitting may be difficult. Typically, broken male threaded pipe fittings are extracted using known devices that generally fall into one of three categories:
One known device for extracting a broken male pipe fitting has a conical or tapered configuration, with left-handed helical teeth, or left-hand sharpened (for extracting right-hand threaded fittings), straight-edged teeth or blades which are co-axial with the axis of the tool. The teeth or blades are typically multiple in number, radially disposed, and equally spaced.
A second known device for extracting a broken male pipe fitting has a tapered pyramid or conical fashion, with a triangular, square, pentagonal, hexagonal, or other regular polygon cross-section. The edges along the cross-sectional corners of this pipe extraction device are sharp which enable them to embed into the inside diameter of the fitting to facilitate extraction.
A third known device for extracting a broken male pipe fitting is of the expanding type. This device has straight or knurled teeth along the longitude of its gripping surface, and expands outwardly to cylindrically engage with the inside diameter of the broken pipe fitting when removal (counter-clockwise) torque is applied to the tool.
All of these devices grip the broken male pipe fitting either partially (conically) or entirely (cylindrically) on an inside diameter of the pipe fitting at or near the exposed and broken edge or mouth of the damaged fitting. These tools can be, but are not always successful for extracting broken metallic (steel, brass, iron or aluminum) pipe fittings in order to reclaim the reusable mating part. However, in the case of non-metallic fittings (plastic, PVC, CPVC, Nylon, etc.) these tools often fail to successfully extract the broken male pipe fitting, due to the fact that the tool pressure exerted upon the contact area is so great, that rather than gripping the male pipe fitting, the tool tends to machine or carve the softer plastic materials. Additionally, the increased elasticity of plastic, in particular, PVC pipe fittings tends to work against extraction efforts because these tools expand the fitting, thereby increasing the necessary removal torque. This in turn destroys the broken fitting to the extent that it can no longer be extracted, rendering the previously usable mating female pipe fitting unusable and therefore scrap.
While known tools for extracting a broken male pipe fitting may have proven useful for certain circumstances, a need for improvement in the relevant art exists.
SUMMARY
This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features.
The present teachings generally provide a tool for engaging a broken fitting entirely on the exposed broken face or edge of the fitting to be extracted. Extraction tools based upon prior art conically or cylindrically engage to the inside diameter at or near the exposed broken edge. The present teachings provide greater gripping effectiveness or capability in terms of utilization of the tool pressure that is applied by the tool to the workpiece (broken fitting) during the extraction process. This minimizes the free machining of the broken fitting which thereby optimizes the extraction torque.
The present teachings provide an extraction technique that also eliminates expansion from within the damaged male pipe fitting by the extraction tool, during the removal process. This, in turn, reduces the necessary removal torque to only that which is required to overcome the original assembly torque, plus any thermal and environmental factors present, as compared to overcoming the original assembly torque, plus overcoming frictional torque created by the expansion of the damaged male pipe fitting in addition to thermal and environmental factors. In the case of extracting non-metallic fittings, the present teachings are particularly advantageous because frequently, the torque required to machine the fitting material by common, present day extraction tools, can be considerably less than the required removal torque. Hence, material is removed from the workpiece fitting by the common, ordinary, present day extraction tool, rather than extracting the fitting from the salvaged piece, in its entirety.
The tool of the present teachings may be made from a variety of materials. Specific material selection may be dependent upon the material from which the workpiece (damaged or broken) male pipe fitting was comprised. For example, mild carbon steels or even aluminum may be adequately suitable, if the tool were intended strictly for use on plastic or Poly Vinyl Chloride (PVC) workpiece fittings. Alternately, if the tool were intended for use on metallic fittings, such as steel or brass, the tool may perform better with a material with a higher carbon content, for tool heat treatment and hardening purposes. In this case, most any file-hard steel, or in extreme cases for longer tool life, high-speed tool steel would be a more suitable choice.
In the case of high volume tool manufacturing and production, the tool may be cast, molded, stamped, forged or even near-net or net-formed powdered metal or sintered metal process manufactured, from the appropriate material that would provide adequate finished tool hardness for its intended application and reasonable tool life expectancy. Carbide, ceramic and porcelain are also viable material options.
In accordance with one particular aspect, the present teachings provide an apparatus for extracting a damaged male threaded pipe fitting from a counterpart female threaded pipe fitting. The apparatus includes a blade portion and a drive shank. The blade portion includes a pair of blade faces and a pair of diametrically opposed, cylindrical pilot diameter segments. The drive shank integrally extends from the blade portion. The apparatus is adapted to engage the damaged male threaded pipe fitting entirely on an exposed broken face or edge of the damaged male threaded pipe fitting.
In accordance with another particular aspect, the present teachings provide a method of extracting a damaged male threaded pipe fitting from a counterpart female threaded pipe fitting. The method includes providing an apparatus including a blade portion and a drive shank. The blade portion includes a pair of blade faces and a pair of diametrically opposed, cylindrical pilot diameter segments. The drive shank integrally extends from the blade portion. The method additionally includes engaging the damaged male threaded pipe fitting entirely on an exposed broken face or edge of the damaged male threaded pipe fitting. Further, the method includes rotating the damaged male threaded pipe fitting relative to the counterpart female threaded pipe fitting to extract the damaged male threaded pipe fitting from the counterpart female threaded pipe fitting.
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. It should be noted that all dimensions shown in all views are exemplary and are in inches.
FIG. 1A is a perspective view of an installed, damaged, male pipe fitting prior to extraction.
FIG. 1B is a perspective view of the male pipe fitting of FIG. 1A shown operatively associated with an extraction device of the present teachings.
FIG. 2A is a side view of an extraction device constructed in accordance with the present teachings.
FIG. 2B is another side view of an extraction device constructed in accordance with the present teachings.
FIG. 2C is a cross-sectional view taken along the line 2 C- 2 C of FIG. 2A .
FIG. 2D is a cross-sectional view taken along the line 2 D- 2 D of FIG. 2A .
FIG. 2E is a cross-sectional view taken along the line 2 E- 2 E of FIG. 2A .
FIGS. 3A-3K provides various views of an extraction device in accordance with the present teachings.
FIGS. 4A-4I illustrates further variations of an extraction device in accordance with the present teachings.
FIGS. 5A-5C provides various views detailing an extraction tool in accordance with the present teachings.
FIG. 6 illustrates the mathematical relationship of the across flat (pilot) dimension to the tool thickness, describing the trigonometric relationship present between the tool thickness and the resultant across flats tool pilot dimension(s) where applicable.
FIGS. 7A and 7B illustrate general steps of a method in accordance with the present teachings.
Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings.
DETAILED DESCRIPTION
Example embodiments will now be described more fully with reference to the accompanying drawings.
The tool or apparatus of the present teachings is identified generally throughout the drawings at reference character 10 . As shown in the views of FIGS. 2A-2E , the apparatus 10 may include a flat blade portion ( 1 ). In one application, the flat blade portion ( 1 ) may be approximately 1/16″ thick or greater, and may form two, flat blade faces ( 2 ). The flat blade faces ( 2 ) may either be parallel or form a slight angle relative to one another. The flat blade faces ( 2 ) may be disposed symmetrically about a pair of axial planes, which are perpendicular to one another.
At one end, these flat blade faces ( 2 ) may be integrally attached to a round drive shank ( 3 ). The length of the drive shank ( 3 ) may vary within the scope of the present teachings. In this regard, the drive shank ( 3 ) may be short, medium or long in length. In an alternate embodiment, a segment near the end of the drive shank portion ( 4 ) may be triangular, square or hexagonal in cross-section shape, or any other regular polygon that will facilitate mounting in a driver device, such as a drill motor, and spinning the tool concentrically about a coaxial axis. This optional configuration is intended to prevent slippage while the tool is inserted into the chuck of the torque providing drive tool, which would again, typically be a drill motor, wrench, or similar device, none of which are part of the present invention. The drive shank ( 3 ) and its axis are concentric with all other diametrically opposed features of the extraction tool.
At the end opposite the drive shank the circumferential periphery of the flat blade portion ( 1 ) may be configured into two diametrically opposed, cylindrical pilot diameter segments ( 5 ). The cylindrical pilot diameter segments ( 5 ) may also be concentric about the drive shank ( 3 ) and a tool axis ( 6 ), and form a pilot diameter ( 7 ) of the apparatus 10 . The pilot diameter segments ( 5 ) may be sized appropriately to provide a close slip-fit into the inside diameter of the broken pipe fitting to be extracted. The pilot diameter segments ( 5 ) maintain the apparatus 10 concentric with a fitting (workpiece), during a broken fitting extraction process. The pilot diameter need only be sufficient enough in longitudinal length to maintain extraction engagement edges ( 8 ) of the apparatus 10 in contact with the exposed broken fitting edge face during the extraction process.
Two extraction engagement edges ( 8 ) may be immediately adjacent and perpendicularly disposed relative to the pilot diameter segments ( 5 ). Alternatively, an angle of the extraction engagement edges ( 8 ) may either be slightly acute or slightly obtuse relative to each of their respective, adjacent associated, pilot diameter segments ( 5 ). An extraction engagement edge diameter ( 9 ) of the extraction tool at the extraction engagement edges ( 8 ), may be of sufficient size to allow full engagement of the extraction engagement edges ( 8 ) to the workpiece's broken fitting edge face, while at the same time, small enough so as not to engage into, or machine the minor diameter of the female thread in the female pipe fitting piece to be salvaged.
Departing from each of the extraction engagement edges ( 8 ) are tool clearance rake angle faces ( 11 ). These faces may form an acute angle with one of their respective adjacent flat blade faces ( 2 ), the vertices of which are at the extraction engagement edges ( 8 ). The angle may be of any reasonable amount less than 90 degrees. However, it should be noted that the lower the angle, the thinner the extraction engagement edges ( 8 ) become, hence more fragile and more susceptible to damage during normal use. Viewing a right-hand thread extraction tool from the bottom with the viewer's line of sight parallel to the tool axis ( 6 ), the tool clearance rake angle faces ( 11 ) are arranged such that they depart from the plane of their respective adjacent extraction engagement edges ( 8 ) in a counter-clockwise fashion and away from the viewer. This arrangement enables the tool to bite into and firmly grip the exposed broken fitting edge face, when the pilot diameter ( 7 ) is inserted into the inside diameter of the broken fitting, and axial force is applied engaging the extraction engagement edges ( 8 ) to the fitting's exposed broken edge.
Proximal to an extractor largest outside diameter and further toward the round drive shank portion ( 3 ), the apparatus 10 may include tool blend areas ( 12 ). The tool blend areas ( 12 ) define a transition area that may afford an opportunity for the apparatus 10 to taper down from the extractor largest outside diameter ( 11 ), to the round drive shank portion ( 3 ). Which, as earlier mentioned, is a round cross-section cylindrical diameter portion, to which can be attached the hexagonal drive shank portion ( 4 ) which is hexagonal or can be any other regular polygon in cross-sectional shape. This also provides an opportunity to blend the tool's shape from the flat blade portion ( 1 ), to the round drive shank portion ( 3 ) and or optional hexagonal (or regular polygon shaped) drive shank portion ( 4 ), previously described. Furthermore, the drive shank ( 3 ) may even be entirely, for its full length, hexagonal, or other regular polygon in cross sectional shape.
Embodiment for a Multiple-Size Extraction Device
To increase the versatility of the apparatus 10 of the present teachings the apparatus 10 may incorporate multiple tool sizes integrated or conjoined together to create a single tool that can be used to extract multiple pipe fitting sizes. In this regard, the apparatus 10 may include multiple steps ( 13 ) fashioned into a single tool so that this single tool may be used to extract more than one size of pipe fitting. Described more specifically, a single tool, designed for multiple fitting sizes, would ideally accommodate the extraction of several consecutive sizes of pipe fittings. For example, the same tool could be designed to extract ½″ and ¾″ as well as 1″ (or greater or lesser) National Pipe Thread pipe fittings. Multiple steps ( 13 ) for additional sizes may either be added to a single tool or grouped together on a separate tool. This can be accomplished by utilizing the extraction engagement edge outside diameter(s) (or flats), which have been designed for the extraction of one size of pipe, as the pilot diameter(s) ( 7 ) for the extraction of the next larger pipe size.
Embodiment for a Left-Hand Thread Extraction Device
Generally, an extraction tool designed for extracting left-hand pipe fittings would embody the same features as one designed for right-hand fittings, except that the features would be arranged in a symmetrically opposite fashion from the similar features on a right-hand thread extraction tool. That is to say that when viewed from the bottom end of the tool, or from its extraction engagement edges ( 8 ) end, with the viewer's line of sight parallel to the tool axis ( 6 ), the tool would have tool clearance rake angle faces ( 10 ), which depart from their respective adjacent extraction engagement edges ( 8 ) on the flat blade portion ( 1 ), in a clockwise rather than counter-clockwise direction. This slightly different, symmetrically opposite embodiment facilitates the extraction tool to grip and rotate the exposed broken fitting edge face and drive the tool in a clockwise direction when the tool pilot diameter ( 7 ) is inserted into the broken fitting, with axial force applied to the tool, to engage the extraction engagement edge(s) ( 8 ) to the broken fitting's exposed edge face. Likewise, the tool would then be driven in a clockwise direction to effect broken fitting extraction of a left-handed thread pipe fitting. However, left-handed thread pipe fittings are extremely rare. Therefore, the majority of the tool devices manufactured and in use would likely be of the right-hand thread extraction variety. It should also be noted that a multiple size left-hand thread male pipe fitting extractor tool, that is, a single tool designed for use on multiple sizes of pipe fittings, could be designed by adding multiple steps ( 13 ), in like fashion to that described previously for the multiple-size right-hand fitting extraction tool.
Additional Embodiment Enhancements and Variations Therein of the Male Pipe Fitting Extraction Device for Extracting Right or Left-Hand Threaded Fittings (Right-Hand Thread Extraction Device Illustrated)
With reference to FIGS. 3A-3K , an alternative apparatus constructed in accordance with the present teachings is illustrated and identified generally at reference character 100 . Given the similarities between the apparatus 10 and the apparatus 100 , like reference characters will be used to identify like features. The apparatus 100 may include a pilot diameter ( 7 ) and/or an extractor largest outside diameter ( 11 ) (or diameters in the case of a multi-size tool) configured into a cylindrical shaped pilot diameter ( 14 ) or any quadrennial segmented pilot diameter ( 15 ) or portion thereof, or a singular or multiple array of extraction edges, either equally or unequally placed about the tool's longitudinal axis. Likewise, cylindrical extraction engagement edge diameter(s) ( 16 ) may also be cylindrical and quadrennially segmented extraction engagement edge diameters ( 17 ), instead of those features being fashioned into a flat blade portion ( 1 ) of the apparatus 10 , as in the preferred embodiment. Again, the apparatus 100 may include singular, or multiple quadrennial segments, ( 18 ) and ( 19 ) respectively, or an extraction edge or a multiple of edges, either equally or unequally spaced about the tool's longitudinal axis. Additionally, the apparatus 100 may include a singular extraction engagement edge ( 20 ). Alternatively, the apparatus 100 may include multiple extraction engagement edges ( 21 ).
Additional features for the apparatus 100 may include slight chamfers ( 22 ) or corner radii ( 23 ) or sharp corners ( 23 A) at the root of the extraction engagement edge(s) ( 8 ) and at the extraction engagement edge tips ( 24 ) on their outer periphery. With the exception of the sharp corner embodiment, these features would further enhance and facilitate insertion of the pilot diameter ( 7 ) into the fitting to be extracted, when the pilot diameter is one and the same as the extraction engagement edge diameter ( 9 ) for the extractor of the next size smaller pipe fitting, as in the case of a multiple-size extraction tool.
In certain embodiments, the apparatus 100 may include flats ( 25 ) on an outer periphery of the pilot diameters ( 7 ) and extraction engagement edge tips ( 24 ), such that the diagonal dimension(s) ( 26 ) were equivalent to the required pilot diameter necessary for piloting the tool into the fitting to be extracted.
Further in certain embodiments, the apparatus 100 may include an undercut ( 27 ) at internal vertices of the pilot diameters to the extraction engagement edge ( 8 ). These undercuts ( 27 ) may either be plunged into the extraction engagement edge ( 8 ), axially (longitudinally) or into the pilot diameter(s) ( 7 ), radially, or both. These features would allow for a “sharp corner” effect in the areas described, by eliminating even the slightest inside corner radius that would have the potential of coming in contact with the broken edge face of the workpiece, which may tend to enhance the gripping capability of the tool to the damaged pipe fitting. The addition of these features may in effect potentially augment the machining of the workpiece, by increasing the tool pressure and thereby improve the gripping effect by the tool on the broken edge face of the fitting to be extracted. Conversely, intentionally forming slight chamfers ( 22 ) or inside and outside corner radii ( 23 ) or sharp corners ( 23 A), into the tool in these regions may improve the gripping effect of the tool by increasing the surface contact area between the tool's extraction engagement edges ( 8 ) and the broken fitting's exposed edge face. An affirmed conclusion regarding the most effective tool design strategy could be derived most effectively through experimentation and development of the tool configuration.
The apparatus 100 may also include slightly tapered pilot diameter(s) or flat(s) ( 28 ) to additionally facilitate pilot insertion into the broken fitting.
It should be noted that the above-mentioned embodiment features could be used in combination with one another, except in cases where two features may be in conflict. For example, if a tool were to have chamfers in a given area, then it would be impossible for those same areas to have corner radii.
Further Alternative Embodiment Features for the Male Pipe Thread Fitting Extraction Device
With reference now to FIGS. 4A-4I , further possible features of the present teachings are illustrated. The extraction engagement edges ( 8 ) may be located above center plane (see FIG. 4D ), on center plane (see FIG. 4E ) or below center plane (see FIG. 4F ), relative to the horizontal longitudinal axis center plane ( 32 ). Each configuration, in theory, is associated with advantages and disadvantages. Again, as earlier mentioned, the most advantageous configuration may only be derived through experimentation. The dimensions shown in this view are not fixed, but rather for illustrative purposes only and may be varied or adjusted without departure from the spirit and intent of the present invention. The “0.062” and “0.031” dimensions were chosen based purely upon practicality. Obviously, the smaller these dimensions are, the weaker the tool becomes, which would tend to increase the risk of breakage during use. It is possible to select more robust materials to make the tool from, which would enable these dimensions to be considerably smaller, but not without cost penalty. These particular embodiment features are completely and entirely compatible with ALL of the other embodiment features.
In one configuration, shown in FIG. 4A , for example, the engagement edge incorporates hook profile extraction engagement edges ( 33 ). The advantages of this design are realized both in the manufacture of the tool, because this engagement edge shape lends itself well to forming rather than machining the tool, as well as in function, whereby the tool has a greater opportunity to bite or dig into the pipe fitting and curl the stock, thereby wedging itself into the broken or damaged male pipe fitting edge, rather than machining it out.
Tool Profile
With reference to FIG. 5 , a typical tool profile having nominal dimensions for a 0.375″ tool thickness is illustrated. These dimensions were developed by test for schedule 40 pipe fittings, and once again, are typical nominals. Again, it should be noted that these dimensions, as well as their tolerances (not shown) may vary slightly, or can be adjusted without departing from the spirit of this invention. These dimensions will also vary with the schedule, grade or wall thickness of the pipe from which the fitting is made. Typically schedule 40 and schedule 80 pipe fittings are most common. The nominal dimensions shown should, under most conditions, perform adequately for both schedules 40 and 80 fittings.
Referring now to FIG. 6 , a mathematical relationship of the across flat (pilot) dimension to the tool thickness is illustrated. This illustration conveys a mathematical means for calculating the required extraction tool pilot “across flats” dimension, given the inside diameter of the pipe fitting to be extracted, hence, the required pilot diameter, while taking into account the (given or specified) thickness of the extraction tool to be designed. This trigonometric relationship between the given, desired or specified pilot diameter, is identical to the relationship of the sides of a right triangle, as is depicted in FIG. 6 . Simply stated, a greater tool thickness, results in a smaller across flats dimension. This is because: if “a” (short or one leg of a right triangle) represents one-half of the extraction tool thickness; and “c” (the hypotenuse) represents the (given & fixed) pilot diameter's radius; where: a2+b2=c2; then: by definition, the greater “a” becomes, the lesser “b” must become, if in fact “c” is fixed and given. The intent of this mathematical relationship is to maintain that “2c” is equal to the fixed and given or desired pilot diameter necessary to fit snugly, yet comfortably into the inside diameter of the male pipe fitting to be extracted. In other words, the pilot diameter circumscribes the quadrilateral shape of the extraction tool's cross section, as in, the pilot diameter circle intersects all four (4) corners of the cross section of the tool. All of the above applies only at the tips of the extraction engagement edge corners.
Using a Right-Hand Thread Pipe Extraction Device
Turning to FIGS. 1A-1B , general steps in accordance with a method of the present teachings are illustrated. The apparatus 10 is inserted into and tightened within a suitable torque transmitting device, such as a reversible drill motor, tap wrench or other type of wrench capable of supplying sufficient removal torque in a counter-clockwise direction. If the torque transmitting device is electric powered, a variable speed device is recommended so that the removal torque may be applied gradually. Switch the torque transmitting device, if applicable, to left-hand or counter-clockwise rotation. Insert the tool's pilot into the inside diameter of the broken fitting to be extracted. While maintaining the tool's axis, coaxial with the broken fitting's axis, apply axial force to the tool with the torque transmitting device and gradually apply torque to the tool in a counter-clockwise direction. Continue to apply downward axial insertion force on the tool and gradually increase the torque until the fitting is fully extracted.
Using a Left-Hand Thread Pipe Extraction Device
The use of an apparatus designed to extract left-hand thread fittings is identical to the use of one designed for right-hand threads, except that the torque must be applied in the opposite or clockwise direction as viewed from the drive shank end of the tool.
Enhanced Extraction Device Features
With reference to FIGS. 9A-9B , still further features optional for an apparatus in accordance with the present teachings are illustrated. In this regard, the extraction apparatus may be enhanced to further diversify its usefulness under more widely varied application conditions in terms of positive male threaded pipe fitting extraction, primarily for, but not limited to use on metallic pipe fittings. Metallic pipe fittings often present a greater challenge while attempting extraction, due to the possibility of corrosion. The apparatus may include an integral drive portion ( 34 ). The integral drive portion ( 34 ) may be hexagonal, square or any other regular or non-regular polygon or quadrilateral shape. The apparatus may further include a retractable grip device shank ( 35 ) that inserts into a longitudinal bore, said bore passes entirely through the enhanced extraction device, said bore being eccentrically oriented, relative to the longitudinal center axis of the extraction tool. Said grip device may have a threaded portion ( 36 ) at one end, either left or right-handed thread, on the exposed outer end. The threaded portion ( 36 ) may thread into an adjustment nut ( 37 ), which may be comprised of a standard hex nut, or a lock nut of the crimped or staked, or plastic insert variety, and having an internal thread suitable for proper fit onto the threaded portion ( 36 ). The adjustment nut ( 37 ), is used to adjust, draw or retract the retractable grip device shank ( 35 ) and hence the grip device foot ( 38 ). The grip device foot ( 38 ), can be round, oval, square, or crescent in plan view shape, as well as any one of a number of shapes, either regular or irregular. The grip device foot ( 38 ) is no larger in overall diametrical size, than the cylindrical shaped pilot diameter ( 14 ), and is an integral part of the retractable grip device shank ( 35 ), along with the threaded portion ( 36 ). The grip device foot gripping surface ( 39 ) may be a plain, smooth surface, or equipped with a singular tooth or a multiple of teeth or knurl ( 40 ), and is also integral to the grip device foot ( 38 ). Said tooth, teeth, or knurl, if so equipped, are such that they are situated on the inboard side of the foot, facing the extraction engagement edges ( 8 ). The tooth or teeth may be situated in any orientation relative to the retractable grip device shank ( 35 ) and its related axis. If the grip device foot gripping surface ( 39 ) is equipped with a singular tooth, or a multiple of teeth, this tooth or teeth may be comprised of one or a number of tooth profile options, either a uniform peak tooth profile or a chisel point tooth profile. The grip device foot gripping surface ( 39 ) is intended to come in contact with the opposing end of the damaged/broken pipe fitting to be extracted. The grip device foot ( 38 ), may be arranged such that it is integrally and eccentrically affixed to the retractable grip device shank ( 35 ). In its “concentric position”, the retractable grip device shank foot ( 38 ) may be concentric with the cylindrical shaped pilot diameter ( 14 ), of the enhanced extraction device. This allows the modified and enhanced extraction device's grip device foot ( 38 ) to pass freely through the inside diameter of the damaged male pipe fitting fully, until the grip device foot ( 38 ) is allowed to reach the opposite side of the pipe fitting to be removed. At this point the extraction engagement edges ( 8 ) would also be in contact with the broken edge face of the damaged fitting on the exposed end. Once the tool is fully inserted and seated, the retractable grip device shank ( 35 ) is rotated to its “eccentric rotated position”, whereby the grip device foot ( 38 ) swings out radially from its previous “concentric position” to allow the grip device foot gripping surface ( 39 ) to align and come in contact with the opposing end of the male threaded pipe fitting to be extracted. If a right-hand thread is employed for the threaded portion ( 36 ), and the adjustment nut ( 37 ), then the rotational direction from the “concentric position” to the “eccentric rotated position” for the retractable grip device shank ( 35 ) would logically, but not necessarily be clockwise. This allows and ensures that as the adjustment nut ( 37 ), is tightened, this encourages the grip device foot ( 38 ) to swing into a position affording greatest possible engagement with the buried, undamaged face or end of the male pipe fitting, which is inside the female pipe fitting to be salvaged. The opposite would be true if a left-hand thread were to be used on the threaded portion ( 36 ), and adjustment nut ( 37 ), i.e. a left-hand thread would desirably and logically, but not necessarily utilize a counter-clockwise rotational direction for radial swing-out engagement of the retractable grip device shank ( 35 ), and the grip device foot ( 38 ). Also, it is logical but not imperative that a tool device designed to extract right-hand thread pipe fittings, utilize a left-hand thread on the threaded portion ( 36 ), and the adjustment nut ( 37 ), and vise-versa for a tool device designed for the extraction of left-hand thread male pipe fittings.
It is at this point that the minor diameter of the female thread fitting to be salvaged, acts as a radial swing stop for the grip device foot ( 38 ). Tightening of the adjustment nut ( 37 ) draws the extraction engagement edges ( 8 ) and the grip device foot ( 38 ) longitudinally closer together. Once the grip device foot gripping surface ( 39 ) and the extraction tool's extraction engagement edges ( 8 ) contact or engage with the opposing end faces of the damaged male pipe fitting, by virtue of tightening the adjustment nut ( 37 ), the damaged male pipe fitting is essentially clamped in between the extraction tool's grip device foot ( 38 ) and the extraction engagement edges ( 8 ). The enhanced extraction device has now essentially become as one with the broken pipe fitting. Now, the extraction tool may be rotated by the drive portion ( 34 ) in the appropriate direction for removal of the damaged pipe fitting, i.e. counter-clockwise for right-hand threaded pipe fittings and clockwise for left-hand threaded pipe fittings, as viewed from the drive portion ( 34 ) end, thus removing or extracting the damaged/broken male threaded pipe fitting.
The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.
Example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.
The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.
When an element or layer is referred to as being “on,” “engaged to,” “connected to,” or “coupled to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to,” or “directly coupled to” another element or layer, there may be no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as “first,” “second,” and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.
Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,” “lower,” “above,” “upper,” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. Spatially relative terms may be intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the example term “below” can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
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The present invention relates to tools or devices which are commonly used for extracting or removing damaged or broken male threaded pipe fittings from their female threaded fitting counterparts. Said damaged male pipe fittings are often removed or extracted as a cost savings measure, in order to salvage the female fitting portion. This avoids the necessity and cost of discarding and replacing both the damaged or broken male fitting, as well as the undamaged female fitting or fittings. This salvage process is especially cost effective in cases where the broken or damaged male pipe fitting in question, is part of a larger, more expensive plumbing assembly or system.
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This application is a continuation of application Ser. No. 436,314, filed Dec. 30, 1982, now abandoned.
BACKGROUND OF THE INVENTION
The present invention concerns a lighted fishing lure.
Diamond lures have heretofore been in use for ocean fishing.
SUMMARY OF THE INVENTION
The present invention concerns a metal lighted fishing lure with a light produced in any color by a light emitting diode powered by two miniature hearing aid batteries 13 series. The batteries are inserted into the metal lighted lure from one end thereof.
The metal lighted lure can also flash by using a flash light emitting diode. Light emitting diodes come in a large color range--manufacturers can produce them in any color.
There has to be at least one hole for the light to exit from interior to the exterior of the solid metal lighted lure. The metal lighted lure has holes drilled for the light to exit and these holes can be in any shape and form. The light illuminates the exterior of the lure.
The metal lighted lure can have as many holes for light to exit as the size of the lure will allow. This light exits from the interior of the light emitting diode to the exterior of the lure in the color of the diode, with steady light, or flash, illuminating reflection, without any loss of flash to the lure.
There are no dead spots, like in the conventional metal lure, which depends on the rays of the sun, and functions only in the day.
The metal lighted lure is lit, or flashes day or night, therefore it is effective day or night, since it has its own source of light.
The diode can be insulated against water entering the chamber of the main body of the metal lighted lure.
Experiments showed applicant herein that fresh or saturated salt water entering the chamber of the main body of the metal lighted lure has no bearing, and the metal lighted lure will give 24 to 30 hours of constant light.
The metal lighted lure can be made from any metal, then chrome plated, but the ideal metal is stainless steel, for it has the desirable silver color and does not tarnish, nor is affected by the salt water, does not need plating and has the weight for deep sea fishing. Polishing would help, but is not required.
The metal lighted lure can also have two lights of different color at the same time, on the exterior of the metal lighted lure, or one light of one color and flash at the same time in any color of choice. There is a good assortment color combination that can be incorporated by the light emitting diodes of choice.
The lure of the present invention is in constant motion when used, and produces constant flash day or night, antagonizing fish to strike the metal lighted lure.
Metal lighted lures are made small and large. Small and light lures are used for fresh water fishing, and large and heavy lures are used for ocean deep sea fishing.
A metal lighted lure of a diamond shape has the advantage that there are no dead spots in producing constant flashing, and can be used day or night--a lure that is effective and productive at night.
Metal lighted lures can also be produced tapered, or cylindrical by a screw machine at the rate of 3000 an hour by one machine.
The metal lighted lure of the present invention does not have to be insulated from fresh or salt water, as the metal lighted lure function for 24 to 30 hours of continuous use, without noticeable discharge.
The metal lighted lure of the present invention can be made with more than one color of light coming from interior to the exterior producing mingling radiant rainbow colors, antagonizing fish to strike the metal lighted lure.
The metal lighted lure can be used to decorate a Christmas tree as a Christmas ornament, or made into a twinkling star, or any decoration, and will not cause a fire. Power can be utilized to produce the singing birds effect--there is no limit to the possibilities.
Metal lighted lures are made on a screw machine. Some other models of metal lighted lures have to be milled, which would reduce the ratio of output, but have the benefit of twisting and thus more antagonizing for fish to strike the metal lighted lure.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows an exploded isometric drawing of a diamond metal lighted lure according to the present invention.
FIG. 2 shows a sectional view of the metal lighted lure of FIG. 1 and shows the light emitting diode energized.
FIG. 3 shows a schematic drawing of the circuit shown in FIG. 2.
FIG. 4 shows on end bottom view of FIG. 1 (the top view of FIG. 1 would be the same, except that it would be all a solid body).
FIG. 5 shows an exploded view of the light emitting diode of FIG. 2 with cathode and anode leads.
FIG. 6 shows an isometric view of another embodiment of a lure according to the present invention showing a lure turned by a screw machine.
FIG. 7 shows a partial sectional view of FIG. 9, and also shows a fishing hook placed inside the end cap before crimping.
FIG. 8 shows a partial sectional view of FIG. 7 with a fishing hook crimped inside the end cap.
FIG. 9 shows an isometric view of another lure according to the present invention.
FIG. 10 shows an isometric drawing of another lure according to the present invention.
FIG. 11 shows a schematic circuit showing a placement of the batteries for the unit to maintain the diode in an "OFF" position.
FIG. 12 shows another schematic circuit showing the placement of the batteries such that it can be used to keep the diode in an "OFF" position.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a lure 18 having a main body 20 with holes 21 drilled partly or all the way through the lure 18. From such holes 21 light will exit from the interior of the lure 18. FIG. 1 also shows drilled holes 22 where a line and hook can be attached (such line and hook not shown in FIG. 1). End cap 28 is disposed on the bottom end of main body 20. End piece 38 is disposed on the top end of the main body 20 or can be part of the main body 20. A lockwasher 27 connects threaded end cap 28 to the main body 20 (this is best seen in FIG. 2). The lure 18 can be made with a threaded end cap on both ends thereof, with a light emitting diode 23 on each side in any color.
FIG. 2 shows the interior of the main body 20 of lure 18. Holes 21 form internal light passageways 30 which connect the interior of the lure 18 to the exterior thereof. In FIG. 2, the light emitting diode 23 is energized by batteries 25. The light emitting diode 23 is pressed into a drilled hole (passageway) 30 in the main body 20 of lure 18, making an electrical connection with the metal body of the main body 20 of lure 18 via lead 33 and serving as well to keep the diode 23 in place. The other lead 34 of the diode 23 makes a series connection with batteries 25, thus completing the electrical loop through a spring 26 with connected batteries 25 to the metal end cap 28, which in turn is thread connected to the metal body of main body 20. The batteries 25 are insulated by a plastic sleeve 24 from the main body 20 formed by the sides of the drilled hole 32 for the diode 23 and batteries 25, thus preventing one battery 25 from shorting the other. Light from diode 23 thus passes from the interior of main body 20 of lure 18 via passageways 30 and exits through holes 21 to the exterior of the lure 18.
In FIG. 6 there is shown another embodiment of a lure according to the present invention. Lure 50 has a main body 52 with drilled holes 51 and drilled holes 53 for possible attachment to a line and hook (not shown in FIG. 6). End cap 58 is at the bottom end of a main body 52 and is connected thereto by lockwasher 57.
In FIG. 7 and FIG. 8, threaded end cap 58 is depicted with a fishing hook 59 at the bottom end thereof. In FIG. 7, the hook 59 is shown inside the end cap before crimping; in FIG. 8, the hook 59 is shown crimped inside the end by a press and die technique.
In FIG. 9, a further embodiment of a lure according to the present invention is depicted. Lure 60 has a main body 62 and an end cap 68 which is connected to main body 62 via lockwasher 67. Holes 61 are drilled into the lure 60. A fishing hook 69 is disposed at the bottom of the lower end piece 65. Lure 60 can be produced on a screw machine. The hook 69 can be crimped to the main body 62 in the same manner as described hereinabove in regard to FIG. 7 and FIG. 8.
FIG. 10 shows a further embodiment of a lure according to the present invention wherein a lure 70 has end caps and 79 of different designs. Lockwasher 77 connects end cap 79 to main body 72 of lure 70 (lure 70 can be produced without lockwasher 77). Drilled holes 71 pierce the lure 70. A hook can be tied through holes 71 in any conventional manner, or a spinner can be attached via a ring, or other means to the lure 70.
FIG. 11 and FIG. 12 depict schematic circuits showing placement of the batteries 25 in relation to the diode 23 so as to maintain the diode 23 in an "off" position to keep the batteries 25 from discharging. This is in comparison to the schematic circuit shown in FIG. 3 which shows the batteries 25 in relation to the diode 23 so as to maintain the diode 23 in an "on" position. Placement of the batteries 25 is important as it can be used as an "on" and "off" switch--to either energize the light emitting diode 23 or shut off the light emitting diode 23 and stop the batteries 25 from discharging.
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A metal fishing lure containing a light emitting diode therein which is in direct communication with one or more passageways formed by one or more holes in the lure. Light is thus allowed to pass directly from the interior of the diode to the exterior thereof. Two miniature hearing aid batteries inserted in the lure power the light emitting diode.
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This application claims priority to Provisional Patent Application Ser. No. 60/856,053, filed on Nov. 1, 2006, which is herein incorporated by reference in its entirety.
This is a divisional application of application Ser. No. 11/982,172 filed on Nov. 1, 2007 now U.S. Pat. No. 7,742,336; issued on Jun. 22, 2010, which is herein incorporated by reference in its entirety and assigned to the same assignee.
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention is related to nonvolatile memories and configurable logic elements and in particular to a configurable logic elements, which is implemented by trapped-charge nonvolatile memory.
2. Description of Related Art
Programmable logic arrays such as program logic arrays (PLA) and field programmable gate arrays (FPGA) comprise configurable logic elements and configurable interconnection paths. Different functions may be implemented upon the same hardware chip by programming the configuration elements, which are conventionally static random access memory (SRAM) or latches connected to pass gates. FIG. 1 shows a programmable logical connection of prior art, in which the pass transistor 11 is connected between two logic areas 13 and 14 . The gate of the pass transistor 11 is connected to a latch 12 . The setting of the latch 12 controls whether or not the pass transistor 11 will be turned on or off. Generally, a latch and/or an SRAM is used to control the state of the pass transistor because the process technology can be simple CMOS. U.S. Pat. No. 4,750,155 (Hsieh) is directed to a five-transistor memory cell which includes two inverters and a pass transistor that can be reliably read and written. However, the disadvantages of using latches and SRAM is that the programmable elements are volatile, which means that the state of the latch and the SRAM must be re-established each time power is turned on.
Non-volatile memory can also be incorporated into the programming configuration elements in the form of fuses or anti-fuses, as well as erasable programmable read-only memory (EPROM) and electrically erasable programmable read-only memory (EEPROM) cells. Fuse-based non-volatile memory (NVM) involves separating segments of wiring paths with a high concentrated current; and are therefore, not re-programmable. U.S. Pat. No. 4,899,205 (Handy, et al.) is directed to an electrically-programmable low-impedance anti-fuse element. However, EPROM and EEPROM devices can be repeatedly programmed, but require high voltages for program and erase. Thicker oxide devices as well as more complex processes are required, which can degrade the chip performance and increase the processing cost.
In general, in an FPGA there are several types and variations of logical connections. In FIG. 1 , two logic areas 13 and 14 are connected together via a NMOS pass gate 11 . Using a single gate provide the best utilization of semiconductor area, but the transmitted signal between the two logic areas is degraded by the VT (threshold voltage) of the transistor 11 . In order to avoid the VT drop, it is also possible to form the connection using a NMOS-PMOS complementary pass-gate, or with a thicker-oxide NMOS transistor and a boosted gate voltage. An FPGA implemented with reprogrammable non-volatile memory incorporated within a logical connection has been implemented by a floating gate type of memory. In U.S. Pat. No. 5,576,568 (Kowshik) a single-transistor electrically alterable switch is directed to a floating gate memory, which is programmed and erased by Fowler-Nordheim tunneling.
In U.S. Pat. No. 6,252,273 B1 (Salter III et al.) a nonvolatile reprogrammable interconnect cell with FN tunneling device for programming and erase is directed to a device configuration in which two floating gate devices share a single floating gate; one device functions as the memory storage device and the other device functions as the logic switch cell. Shown in the prior art of FIG. 2 , the source and drain of the logic switch cell 17 is connected to a logical array, whereas the source and drain of the memory storage 18 can be biased to program and erase electrons to and from the common floating gate. Programming and erasing the switch transistor 17 is effected entirely by the tunneling in the electron tunneling device 19 . The two main advantages of this device is smaller area than a typical SRAM device, and non-volatility. Thus, the logic array containing the device of FIG. 2 is already configured upon boot-up; however, having a floating gate device in the path of logic could have a negative impact on speed, because a thicker oxide device is slower. One way to reduce the speed disadvantage is to lower the threshold voltage of the floating gate logic switch 17 until it becomes a negative value, thus increasing the current drive of the device.
U.S. Pat. No. 5,587,603 (Kowshik) is directed towards a zero power non-volatile latch consisting of a PMOS floating gate transistor and an NMOS floating gate transistor, with both devices sharing the same floating gate and control gates. Shown in FIG. 3 , the drains of the devices are also connected together to form the output terminal, which is generally applied to the gate of the logic switch gate. Storage of electrons in the common floating gate will determine whether the logic switch gate is on or off.
U.S. Pat. No. 5,587,603 (Kowshik) a two-transistor zero-power electrically-alterable non-volatile latch is directed to a latch consisting of a PMOS floating gate transistor 22 and an NMOS floating gate transistor 23 where both devices share the same floating gate 24 and control gates as shown in FIG. 3 . The drains of the transistors are also connected together to form the output terminal 25 , which is generally applied to the gate of the logic switch gate. Storage of electrons in the common floating gate determines whether the logic switch gate is on or off.
The preceding and other prior art, such as NVM in programmable logic, have been implemented with floating gate types of flash memory. However there has been a recent trend to use charge trap mediums instead of floating gate to store charge. In embedded CMOS applications like NVM programmable logic, trap-charge memories provide better reliability, good scalability, simple processing and in some cases, lower voltage operation.
Four basic types of trap-based memory cells are shown in FIGS. 4 a , 4 b , 4 c and 4 d . FIG. 4 a shows a basic planar structure in which nitride or some other trap material 401 is placed under the control gate MGATE. Here charge is stored uniformly throughout the trap film 401 . Electrons are injected and ejected by tunneling through the channel. Voltage conditions for program and erase are given in TABLE 1a. If the tunneling mechanism utilized is direct tunneling, the bottom oxide thickness should be thin, on the order of approximately twenty Angstroms. If the tunneling mechanism used is Fowler-Nordheim, then the bottom oxide thickness can be thicker than approximately 40 Angstroms, but higher voltages may be needed. Several types of band gap engineered oxides are currently being investigated in the industry, which may reduce the voltage requirement during Fowler-Nordheim tunneling.
SUMMARY OF THE INVENTION
It is an objective of the present invention to introduce a non-volatile configuration element for programmable logic arrays, using trap-based memory devices, rather than a floating gate memory devices.
It is further an objective of the present invention to provide a single integrated device comprising a word gate portion surrounded by two trap charge storage portions on a single channel, wherein the output of the single integrated device is the channel directly under the word gate portion.
It is still further an objective of the present invention to provide a trap charge insulator between a semiconductor oxide and a control gate, wherein the trap charge insulator is a nitride film, a nano crystal film or any other insulator film material that can suitably provide nonvolatile charge storage.
Four basic types of trap-charge storage cells are shown in FIGS. 4 a , 4 b , 4 c and 4 d . FIG. 4 a shows a basic planar structure in which a nitride 401 , or equivalent material, is placed under the control gate MG. Here charge is stored uniformly throughout the trap film 401 . Electrons are injected and ejected by tunneling through the channel. Voltage conditions for program and erase are given in TABLE 1a. If the tunneling mechanism utilized is direct tunneling, the bottom oxide thickness should be thin, on the order of approximately twenty Angstroms. If the tunneling mechanism used is Fowler-Nordheim, then the bottom oxide thickness can be thicker than approximately 40 Angstroms, but higher voltages may be needed. Several types of band gap engineered oxides are currently being investigated in the industry, which may reduce the voltage requirement during Fowler-Nordheim tunneling.
TABLE 1A
Operation
Mechanism
NB
VML
MG
Read
Channel read
1.5
0
1.5
Program
Direct tunneling
0
0
15
Erase
Direct tunneling
15
15
0
FIG. 4 b shows the same structure as FIG. 4 a ; however in this cell, charge is stored at the edges of the nitride film, as denoted by the dotted circle 402 . It should be noted that for dual storage, it is possible to use both edges of the nitride film. The voltages for operation on the single side 401 are given in TABLE 1b.
TABLE 1B Operation Mechanism NB VML MG Read Reverse read 1.5 0 1.5 Program CHE injection 0 8 10 Erase Hot hole injection* 8 8 −7 (erase both sides)
A single sided split gate structure with a nitride film 403 under the split gate is shown in FIG. 4 c , and the corresponding voltage operation table is given in TABLE 1c.
TABLE 1C
Operation
Mechanism
NB
VML
MG1
MG2
Read
Reverse read
1.5
0
1.5
1.5
Program
CHE injection
0
5
1
5
Erase
Hot hole injection
0x
5
0 to −3
−3
FIG. 4 d shows a twin split gate structure with nitride film 404 under both twin split gates, and the voltage operation table is given by TABLE 1d.
TABLE 1D
Operation
Mechanism
NB
VML
MG1
MG2R
MG2L
Read
Reverse read
1.5
0
1.5
1.5
1.5-2.5
Program
CHE injection
0
5
1
5
1.5-2.5
Erase
Hot hole injection
0x
5
0 to −3
−3
−3
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will be described with reference to the accompanying drawings, wherein:
FIG. 1 shows a programmable logical connection of prior art;
FIG. 2 is a non-volatile programmable interconnect cell of prior art;
FIG. 3 is an electrically alterable, zero power non-volatile latch of prior art;
FIGS. 4 a , 4 b 4 c and 4 d show basic types of trap-based memory cells;
FIG. 5 is a schematic diagram the preferred embodiment of the present invention;
FIG. 6 is a cell layout of the preferred embodiment of the present invention;
FIG. 7 is an equivalent circuit of the preferred embodiment of the present invention;
FIG. 8 is a schematic diagram of a second embodiment of the present invention;
FIG. 9 is a timing diagram of the second embodiment of the present invention;
FIG. 10 is a schematic diagram of the third and fourth embodiment of the present invention;
FIG. 11 is a schematic diagram of the fifth embodiment of the present invention;
FIG. 12 is a schematic diagram of the sixth embodiment of the present invention;
FIG. 13 is a state diagram for programming and erase of the sixth embodiment of the present invention;
FIG. 14 is a cross section of a PMOS device used in the seventh embodiment of the present invention; and
FIG. 15 is a schematic diagram of the seventh embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A circuit diagram of the preferred embodiment is shown in FIG. 5 . An integrated dual storage site device M 5 with an output OUT is connected to a gate of a Switch 1111 , which in turn is connected between two logic elements 1113 and 1114 . The switch state of the switch 1111 is controlled by the programmed state of the of the two storage sites MH and ML. The storage elements MH and ML are an insulator formed over the initial oxide of the device, for example a nitride film or a nano crystal film that traps charge.
The dual storage site device M 5 is comprised of a word gate device portion 1108 that is sandwiched between a high side storage device portion 1109 , which is connected to a high bias BH and a low side storage device portion 1110 , which is connected to a low bias BL. A diffusion connected the channel under the word gate device portion 1108 forms an output OUT that is connected to the gate of the logic interconnect switch 1111 . A CMOS transistor, controlled by a signal PDN connects the output OUT to circuit ground when the storage sites MH and ML are being programmed or erased.
A word gate signal WG is connected to the word gate device portion 1108 , a control gate signal CGH is connected to the control gate of the high side storage device 1109 , and a control gate signal CGL is connected to the control gate of the low side storage device portion 1110 . The word gate signal WG and the two control gate signals CGH and CGL are used to program, erase the stored charge in the two storage sites MH and ML and to allow reading of the storage device M 5 from which a signal is connected to logic interconnect transistor 1111 to turn the logic interconnect transistor on or off. TABLE 2 shows the various voltages necessary for program, erase and read the storage device M 5 . In order for the switch state to be “off” in the read mode, the storage site MH is programmed to produce a high threshold voltage for upper storage device portion 1109 and storage site ML is erased to produce a low threshold voltage for the lower storage device portion 1110 , allowing a low logic voltage, 0V, to be connected to the logic interconnect transistor 1111 , which turns off the logic interconnect transistor. To turn on the logic interconnect transistor 1111 , the storage site ML is program creating a high threshold voltage in the lower storage device portion 1110 , which blocks the low bias BL from the word gate channel portion 1108 and the storage site MH is erased, creating a low threshold voltage in the upper storage device portion 1109 to allow the high bias BH to the word gate channel portion 1108 . The storage sites MH and ML are programmed by channel hot electron injection and erased by hot hole erase.
TABLE 2
Mode
WG
CGH
CGL
BH
BL
PDN
OUT
Switch State
Read
2.5
1.5
1.5
1.5
0
0
0
OFF
Read
2.5
1.5
1.5
1.5
0
0
1.5
ON
Program MH
1.0
+5.0
−3.0
5
5
1.5
0
OFF
Erase ML
Erase MH
1.0
−3.0
+5.0
5
5
1.5
0
OFF
Program ML
Program
1.0
+5.0
+5.0
5
5
1.5
0
OFF
both
MH & ML
Erase both
1.0
−3.0
−3.0
5
5
1.5
0
OFF
MH & ML
In FIG. 6 is shown a semiconductor layout for the memory device M 5 of the preferred embodiment. The channel under the three device portions 1108 , 1109 and 1110 ( FIG. 5 ) is shown connected to the three diffusions for BH, BL and OUT. Overlaying the channel are the two control gates CGH and CGL and the word gate WG. Under the control gates CGH and CGL are located the stored charge insulator films MH and ML, respectively. The channel of the storage device M 5 is a center-tapped channel where OUT is the center tap connected to the portion under the word gate WG and connects the voltage of the channel under the word gate to the logic interconnect device 1111 .
The diagram of FIG. 7 provides an equivalent circuit of the storage device M 5 of the preferred embodiment. The word gate device 1108 in the equivalent circuit is located in three places, connected to the upper trap charge storage device 1109 , connected to the lower trap charge storage device 1110 and connected to OUT where the connection to OUT forms a center-tap of the channel of the storage device M 5 .
In FIG. 8 is shown the second embodiment of the present invention. A P-channel transistor 515 is connected to a memory gate storage transistor 516 a between a high voltage VMH and a low voltage VML. The storage transistor 516 a is nonvolatile trap charge device where the trap charge element 516 b is formed by an insulator, for example a nitride film or a nano-crystal film. The connection between the P-channel transistor 515 and the storage transistor 516 a forms a node NB, which is connected to a latch 512 through a write control gate 517 . The state of the latch 512 controls the on-off state of the logic interconnect transistor, which couples two logic functions 513 and 514 together when the logic interconnect transistor is turned on.
Continuing to refer to FIG. 8 , the write control gate 517 is opened twice in the process of setting the latch 512 , first to reset the latch to a high state and second to program the state of the latch. The latch is reset to a high logic state using the precharge transistor 515 where the node NB is charged to a high value. With the precharge transistor 515 and the word control gate 517 off, the storage transistor 516 a is turned on. If the storage transistor is programmed to a low state (no trapped charge) the node NB will fall to a value equal to VML. When the word control gate is turned on for the second time, the state of the latch 512 is switched to a low state. If the storage transistor is programmed to a high state (trapped charge), the node NB remains in the high voltage state, and when the write control gate is turned on a second time, the latch remains in the high state. FIG. 9 shows the timing of the PCHG signal connected to the precharge transistor 515 , the WCG signal connected to the word gate transistor 517 and the MG signal connected to the storage transistor 516 a.
In FIG. 10 is the schematic diagram of the third and fourth embodiments of the present invention. Two NMOS storage transistors MH and ML are connected in series between a high bias BH and a low bias BL. The storage transistors MH and ML are nonvolatile and are formed with a charge storing insulator film 710 under the gate of each storage transistor. The charge storing insulator 710 , which lays between the oxide formed over the semiconductor substrate and the gate of each storage transistor, is an insulator which is capable of storing a charge, for example a nitride film or a nano crystal film. Electrons are injected or ejected from the charge storing insulator 710 using Fowler-Nordeim tunneling or direct tunneling. The two storage transistors are allow two programmed states, where (1) the upper storage transistor MH is programmed to block the bias voltage BH and the lower storage transistor ML is erased to allow the low bias BL to be connected to the pass transistor 715 ; and (2) the lower storage transistor ML is programmed to block the bias voltage BL and the upper storage transistor MH is erased to allow the high bias BH to be connected to the pass transistor 715 .
Continuing to refer to FIG. 10 , the storage transistors MH and ML are decoupled from the logic interconnect transistor 711 during programming and erase operations by the pass transistor 715 , the grounding transistor 717 and the data transistor 716 . When the gate of the pass transistor 715 is high, the storage transistors MH and ML control the logic interconnect transistor. When the gate of the pass transistor is low, the gate of the logic interconnect transistor is grounded by the grounding transistor 717 to turn off the logic interconnect transistor 711 and protect the logic interconnect transistor from the high voltages of the erase and program operations of the two storage transistors MH and ML. The storage transistors MH and ML are programmed and erased in the third embodiment of the present invention by tunneling electrons to and from the respective channel. TABLE 3 provides a tabulation of the approximate voltages required to program and erase the storage transistors MH and ML as well as read the state of the storage transistors connected to OUT through the pass transistor 715 to operate the logic interconnect transistor 711 . The switch state of the logic interconnect transistor is “off” when the upper storage transistor MH is programmed and the lower storage transistor is erased to allow the low bias voltage BL to be connected to OUT thorough the pass transistor 715 . The switch state of the logic interconnect transistor 711 is “on” when the lower storage transistor ML is programmed and the upper storage transistor MH is erased, which allows the high bias voltage BH to be connected through the pass transistor 715 to be connected to OUT through the pass transistor 715 . The voltages shown under “PASS” in TABLE 3 are the required PASS BAR voltages connected to the gates of the data transistor 716 and the grounding transistor 717 . The higher voltage of (15) is required to allow the data transistor 716 to couple 15 V from DATA to the storage transistors MH and ML during the high voltage erase operation.
TABLE 3
Mode
WGH
WGL
BH
BL
DATA
PASS
OUT
Switch State
Read
1.5~2
1.5~2
1.5
0
X
2.5
0
OFF
Read
1.5~2
1.5~2
1.5
0
X
2.5
1.5
ON
Program ML
0
15
0
0
0
0
0
OFF
Program MH
15
0
0
0
0
0 (2.5)
0
OFF
Erase ML & MH
0
0
15
15
15
0 (15)
0
OFF
Erase ML
0~2+
0
0
15
15
0 (15)
0
OFF
Erase MH
0~2+
0
15
0
15
0 (15)
0
OFF
TABLE 4
WGH =
Switch
Mode
WGL
BH
BL
DATA
PASS
OUT
State
Read
1.5~2
1.5
0
X
2.5
0
OFF
Read
1.5~2
1.5
0
X
2.5
1.5
ON
Program ML
8
0
10
0
0
0
OFF
Program MH
8
0
10
10
0 (11)
0
OFF
Erase ML
−5
7
0
0
OFF
Erase MH
−5
7
0 (8)
OFF
Erase
−5
7
0
0 or 7
0 (2.5)
0
OFF
Unselected MH
In the fourth embodiment of the present invention, the storage transistors MH and ML (circuit shown in FIG. 10 ) are programmed by channel hot electron tunneling and erased by hot hole injection, where the approximate voltages are shown in TABLE 4. As can be seen comparing tables 3 and 4 the program and erase voltages are different and the voltages in the PASS column in parenthesis are for the PASS BAR voltages needed to allow the higher DATA voltages to be connected to the storage transistors MH and ML.
In FIG. 11 is shown a circuit diagram of the fifth embodiment of the present invention. There are two storage devices MH and ML, which are single sided split gate devices using an insulator 810 to trap charge. A nitride film or a nano crystal film forms the charge storage insulator, which is located under the control gate of the storage element. Node 0 , formed at the connection between the two storage devices, is connected through a pass gate 815 to OUT which is connected to the gate of the logic interconnect transistor, which connects between two logic functions 813 and 814 . The data gate 816 and the grounding gate 817 are controlled by a PASS BAR signal which allows program and erase data to be connected to Node 0 and the gate of the logic interconnect transistor to be grounded.
The two storage devices MH and ML are connected in series between a high bias BH and a low bias BL. The word gates of the split gate storage devices are connected together and controlled by a word gate signal WG. The control gate of the split gate storage element of the upper storage element MH is controlled by a control gate signal CGH, and the split gate control gate of the lower storage element ML is controlled by a control gate signal CGL. TABLE 5 provides the approximate voltages required to program and erase the storage devices MH and ML and as well as read the state of the storage devices coupled to OUT through the pass transistor 815 to operate the logic interconnect transistor 811 which connects between two logic functions 813 and 814 . The numbers in the PASS column in parentheses are approximate values for PASS BAR with the “x” indicates that other values can be used. Programming is done with hot electron tunneling and erase is performed with hot hole injection into the stored charge insulator. The switch state is “off” when the upper storage device MH is programmed and the lower storage device ML is erased, which allows the low bias voltage BL to be connected to Node 0 and through the pass transistor 815 to OUT and the gate of the logic interconnect transistor 811 . The switch state is “on” when the lower storage device ML is programmed and the upper storage device MH is erased, which allows the high bias voltage BH to be connected to Node 0 and through the pass transistor 815 to OUT and the gate of the logic interconnect transistor 811 .
TABLE 5
Mode
WG
CGH
CGL
BH
BL
DATA
PASS
NODE0
OUT
Switch State
Read
2.5
2.5
1.5 to
2.0
0
x
2.5
0
0
OFF
2.5
Read
2.5
2.5
1.5 to
2.0
0
x
2.5
2.0
2.0
ON
2.5
Erase ML &
0 to −2
−3
−3
0
4
4
0(7x)
4
0
OFF
MH
Program ML
1.0
0
5
0
5
0
0/7x)
0
0
OFF
Program MH
1.0
5
0
0
0
5
0(7)
5
0
OFF
Erase ML
0 to −2
0x
−3
0
4
0x
0(7x)
0x
0
OFF
Erase MH
0 to −2
−3
0x
0
0x
4
0/(7)
4
0
OFF
FIG. 12 shows the circuit diagram of the sixth embodiment of the present invention. An upper split gate storage device MH is connected to a lower split gate storage device ML between two bias voltages BH and BL. Each split gate storage device MH and ML are formed by a word gate portion 908 and a split gate portion 909 . A storage site comprising a charge trapping insulator 910 is located under the gate of the split gate portion 909 . The charge trapping comprises a nitride film or a nano crystal film. The control gate and the word gate of each storage devices MH and ML are common and connected to a control gate high CGH signal and a control gate low CGL signal, respectively. The connection between the upper and lower split gate storage device forms Node 0 , which is connected to OUT and the gate of the logic interconnect transistor 911 through the pass transistor 915 . The logic interconnect transistor 911 couples between two logic functions 913 and 914 . The gate of the grounding transistor 918 is connected to the low bias voltage BL, which turns on the grounding transistor 918 during program and erase operations.
Since the control gate and the word gate are common in the storage devices MH and ML of the sixth embodiment of the present invention a special sequence of erase and program operations are necessary. FIG. 13 provides a state diagram of the program and erase order for the storage devices in FIG. 12 . Either ML or MH can be in the program state. The other storage site must be in the erase state. If the low storage device ML is programmed and if the high storage device MH is to be programmed, then the low storage device ML is first erased before the storage high device MH is programmed. If the storage low device ML is to be programmed, then the storage high device MH is erased before storage low ML is programmed.
TABLE 6 provides the approximate voltages needed to program, erase and read the storage devices of the sixth embodiment of the present invention. The state of the switch 911 is “off” when the upper storage device MH is programmed and the lower storage device ML is erased. Conversely, the state of the switch is “on” when the upper storage device MH is erased and the lower storage device ML is programmed. The insulator storage elements are programmed by hot electron tunneling and erased using hot hole injection
TABLE 6
Mode
CGH
CGL
BH
BL
PASS
NODE0
OUT
Switch State
Read
2.5
1.5-2.5
1.5-2.0
0
2.5
0
0
OFF
Read
2.5
1.5-2.5
1.5-2.0
0
2.5
1.5
1.5
ON
Erase ML
0x
−3
0x
5
Float 0x
0
0
OFF
Program MH
5
6
0
5
0
0
0
OFF
Erase MH
−3
6
0
5
0
5
0
OFF
Program1 ML
0
5
0
5
0
5
0
OFF
In embodiment 7 of the present invention a P-channel split gate storage device with an insulator film 1510 for storing charge is shown in the cross section of FIG. 14 . This P-channel split gate storage device MP 6 is connected to the high bias BH in FIG. 15 . An N-channel split gate storage device MN 6 is connected to MP 6 forming OUT, which is connected to the gate of the logic interconnect transistor 1511 . The logic interconnect transistor couples logic functions 1513 and 1514 . A grounding transistor 1518 is connect between OUT and ground to connect OUT to ground during program and erase operations under the control of the signal PDN. The N-channel split gate storage device MN 6 comprises a word gate portion 1507 connected to a word gate signal WGN and a control gate portion 1506 containing a charge storing insulator film 1510 is connected to a control gate signal CGL. The control gate portion 1506 is further connected to a low bias BL. The P-channel split gate storage device comprises a control gate portion 1509 and a word gate portion 1508 . The P-channel control gate portion 1509 contains a charge storing insulator film 1510 , and is connected to a control gate signal CGH. The P-channel word gate portion 1508 is connected to a word gate signal WGP and to the word gate portion 1507 of the N-channel split gate device MN 6 .
Programming charge onto the insulator 1510 of the P-channel split gate device MP 6 raises the threshold voltage of the control gate portion 1509 of the P-channel split gate device MP 6 , which blocks BH from OUT. Erasing charge from the insulator 1510 of the N-channel split gate device MN 6 lowers the threshold voltage of the control gate portion 1506 of the N-channel split gate device MN 6 allowing BN to be connected to OUT and controlling the logic interconnect transistor 1511 “off”. Programming charge onto the insulator 1510 of the N-channel split gate device MN 6 raises the threshold voltage of the control gate portion 1506 of the N-channel split gate device MN 6 , which blocks BL from OUT. Erasing charge from the insulator 1510 of the P-channel split gate device MP 6 lowers the threshold voltage of the control gate portion 1509 of the N-channel split gate device MP 6 allowing BH to be connected to OUT and controlling the logic interconnect transistor 1511 “on”.
While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the spirit and scope of the invention.
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A nonvolatile trap charge storage cell selects a logic interconnect transistor uses in programmable logic applications, such as FPGA. The nonvolatile trap charge element is an insulator located under a control gate and above an oxide on the surface of a semiconductor substrate. The preferred embodiment is an integrated device comprising a word gate portion sandwiched between two nonvolatile trap charge storage portions, wherein the integrated device is connected between a high bias, a low bias and an output. The output is formed by a diffusion connecting to the channel directly under the word gate portion. The program state of the two storage portions determines whether the high bias or the low bias is coupled to a logic interconnect transistor connected to the output diffusion.
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[0001] This Application is a continuation of application Ser. No. 09/891,079, filed by present Applicant, which is related to Provisional Patent Application No. 60/214,677, filed by present Applicant Joseph Massaro, on Jun. 27, 2000.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention is a portable ramp system particularly intended to assist temporarily handicapped persons with transport in and out of houses and buildings. Specifically, the system consists of several modular ramp members removably attached to one another to allow convenient wheelchair access to the application in question. Preferably constructed of wood, the members consist of hingedly-attached starter, rise, and straight panels, which may be folded down to a relatively compact size for the purpose of removal and transport. In addition, the system may include collapsible railing members to further assist the user. Finally, the horizontal panels of the ramp system may include a skid-resistant surface for the utmost in wheelchair traction. As such, the ramp system meets applicable ADA guidelines and provides a quick, convenient, and relatively inexpensive means for temporarily handicapped persons to access houses and similar structures.
[0004] 2. Description of the Prior Art
[0005] Numerous innovations for ramp systems have been provided in the prior art that are described as follows. Even though these innovations may be suitable for the specific individual purposes to which they address, they differ from the present invention as hereinafter contrasted. The following is a summary of those prior art patents most relevant to the invention at hand, as well a description outlining the differences between the features of the present invention and those of the prior art.
[0006] 1. U.S. Utility Patent 5,933,898, invented by Estes et al., entitled “Portable Wheelchair Ramp”
[0007] In the patent to Estes, a series of hingedly connected spanning panels is provided. Each spanning panel includes two opposing outer edges. Alternating ones of the spanning panels include a raised ridge disposed along each of the outer edges of the spanning panel. At least one sleeve is disposed along each of the outer edges of a plurality of the spanning panels. A plurality of elongated rods are provided. Each of the rods is configured to pass through a plurality of the sleeves, the rods thereby maintaining the spanning panels in a substantially fixed linear relationship to one another. An end panel is hingedly connected to each end of the series of hingedly connected spanning panels. Each of the end panels is substantially wedge shaped and includes a gripping surface.
[0008] 2. U.S. Design Pat. Des. 373,885, invented by Holland, Jr., entitled “Telescopic Ramp”
[0009] The design patent to Holland, Jr. describes an ornamental design for a telescopic ramp, as shown.
[0010] 3. U.S. Utility Patent 3,818,528, invented by Peterson, entitled “Portable Ramp For Wheel Chairs And The Like”
[0011] The patent to Peterson describes a portable ramp embodying a number of longitudinal ramp members disposed side by side, each including a number of separate ramp sections arranged end to end, and hinges joining the adjacent ramp members and the adjacent ramp sections of each member in a manner such that the ramp may be folded laterally and endwise between an expanded configuration of use and a collapsed configuration in which the ramp may be conveniently stored and transported. The ramp is intended primarily for use as a wheel chair ramp for steps and the like, although the ramp may be used for other purposes.
[0012] 4. U.S. Utility Patent 5,517,708, invented by Baranowski, entitled “Community Pathway Access System For Wheelchair Users”
[0013] In the patent to Baranowski, an access pathway is provided as a device that may be temporarily or portably deployed for wheelchair users accompanied by an assistant. The device, which is a pathway that may be carried by the user or provided at a site when required, is installed in cooperation with a pre-existing anchor at the site, and may be subject to temporary loan, such as from a central community service provider or a library. A convenient and inexpensive system is thus provided that achieves wheelchair access in many circumstances.
[0014] 5. U.S. Utility Patent 5,214,817, invented by Allen, entitled “Modular Ramp And Landing Walkway Assembly”
[0015] The patent to Allen describes a modular ramp and landing assembly made from a plurality of similarly sized pre-manufactured concrete filled rectangular panels. The ramp portion is made from the modular panels attached by their shorter sides. A support post with an angularly arranged bracket is placed beneath the corners of adjacent panels to secure them together as well as support them. The landing or horizontal portion of this assembly comprises a similarly sized rectangular panel the long side of which is in abutting relationship with the short side of the end of the ramp. Fastener receivers are equi-spaced in duplicate patterns from each corner through the bottom edge of each panel. The size of the panels and the spacing of the fastener receivers are such that minimum support legs and brackets may be utilized in constructing this assembly at a final site.
[0016] 6. U.S. Utility Patent 4,945,595, invented by Meriweather, entitled “Modular Ramp Assembly”
[0017] The patent to Meriweather describes a lightweight pedestrian ramp assembly for bridging a span of open water between two marine structures is readily adaptable in length and width to meet existing site requirements. The ramp assembly is constructed of successive elongated ramp units, each of which is in turn constructed of adjacent, elongated channel shaped fiberglass modules defining a planar walking surface across the backs of the channel webs.
[0018] 7. U.S. Utility Patent 5,671,496 invented by Smith, entitled “Portable Wheel Chair Ramp”
[0019] The patent to Smith describes a wheel chair ramp comprising a plurality of leaves extending in the direction of intended use of the ramp. The leaves are joined together by flexible hinges so that the leaves may be folded to a stalked condition. The flexible hinges are formed by fabric straps attached to the sides of the leaves and passing between adjacent leaves.
[0020] 8. U.S. Utility Patent 5,446,937, invented by Haskins, entitled “Modular Ramp System”
[0021] The patent to Haskins describes a modular ramp system for use with a threshold which has an offset. The modular ramp system includes a number of elements which may be arranged in various combinations in order to conform to offsets of varying height.
[0022] 9. U.S. Utility Patent 5,894,618, invented by Jacobsen et al., entitled “Ramp System”
[0023] The Jacobsen et al. invention relates to a ramp system. The ramp system includes a riser component with a first side and second side that meets the first. The second side and first form an angle less than 90°. The system also includes an adjuster component positionable within the riser. The adjuster component lifts one end of the first side so that an angle that the second makes with the horizontal is increased compared to an angle made between the second side and the horizontal without the adjuster component.
[0024] 10. U.S. Utility Patent 3,995,832 invented by Wiese, entitled “Collapsible Bleacher Rail”
[0025] The patent to Wiese describes a collapsible bleacher railing in conjunction and for use with a collapsible bleacher section or sections, which includes normally vertical, upright, support sections having a plurality of telescoping handrail sections therebetween such that as the bleachers are moved to their relative locations, the handrail will extend and collapse therewith and therefore eliminate the requirement for removal from the bleacher sections.
[0026] 11. U.S. Utility Patent 5,237,932, invented by Edwards, entitled “Collapsible Railing”
[0027] The patent to Edwards describes a collapsible railing having an upper rail and a plurality of posts hingedly attached to the upper rail at spaced apart locations. A crank including a shaft portion and an arm portion which is mounted for rotation about the long axis of the shaft portion is connected to each post. An actuator actuates the motion of the crank to pivot the posts and the upper rails between a collapsed position in which each post is oriented generally horizontally, and an erect position in which the posts are in an upright position.
[0028] 12. U.S. Utility Patent 6,009,586, invented by Hawkes et al., entitled “Truss And Panel System For Access Ramps”
[0029] The patent to Hawkes et al. describes a ramp structure which may be constructed quickly to provide temporary or permanent access to all individuals between two areas of different elevation. A truss design allows long spans to form a bridge without the need for intermediate supports and related support foundations. A truss cross-connector is firmly wedged in place between two trusses and allows the quick, solid joining of two trusses without fasteners to form a strong and stable assembly to serve as ramps, bridges, elevated walkways, etc. The truss cross-connector has resistance to bending and supports the edge of a surface panel and provides a retaining pocket for the surface panel. The truss cross-connector firmly supports the trusses in an upright position when the trusses are used as railings. Surfacing panels placed between the truss cross-connectors provide a quality, long lasting surface which is quickly installed for temporary or permanent installations. The truss cross-connector also prevents casual removal of a closely fitting surface panel. A special tool is included in the system for easy disassembly of light trusses of this design without damage to the components. The design of the ramp system can be easily disassembled and reused for temporary or permanent installations and meets Americans with Disabilities Act guidelines.
[0030] As outlined above, the prior art patents that relate to temporary or portable ramps largely entail elements such as: telescopic panels; panels held together by fabric straps; portable ramps intended to bridge water; and portable ramps intended to assist the user in entering and exiting vehicles. Generally, such prior art patents describe relatively small portable ramps, rather than stronger, more stable ramp systems that may be installed for several months and then removed. Collapsible railings appear in certain prior art patents, but such inventions mostly relate to bleachers and seating assemblies.
[0031] In contrast to all of the above, the present invention is a system of hingedly-attached wooden starter, rise, and straight ramp panels which may be folded down to a compact size for removal and transport. The system includes collapsible railing members and a skid-resistant surface for enhanced safety and general effectiveness.
SUMMARY OF THE INVENTION
[0032] As noted, the present invention is a portable ramp system intended to assist handicapped persons with transport in and out of houses and buildings.
[0033] Accordingly, it is an object of the invention to provide a system consisting of several modular ramp members removably attached to one another to allow convenient wheelchair access to the application in question.
[0034] It is an additional goal of the invention to provide a ramp system constructed of wood, for the purposes of strength and durability.
[0035] It is another object of the invention to provide a ramp system consisting of hingedly-attached starter, rise, and straight panels, which may be folded down to a relatively compact size for the purpose of removal and transport.
[0036] Furthermore, it is a goal of the present invention to provide a ramp system which may include collapsible railing members to further assist the user.
[0037] It is another object of the invention to provide a system featuring horizontal panels which include a skid-resistant surface for the utmost in wheelchair traction.
[0038] Finally, it is an important goal of the present invention to provide a temporary ramp system that meets all applicable ADA guidelines and provides a quick, convenient, and relatively inexpensive means for temporarily handicapped persons to access houses and similar structures.
[0039] The novel features which are considered characteristic for the invention will be set forth in the claims when submitted. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the description of the embodiments to be submitted when read and understood in connection with accompanying figures.
BRIEF DESCRIPTION OF PREFERRED EMBODIMENTS
[0040] [0040]FIG. 1 is a display of basic modular components of the present system including starter portion, rise members, straight members, and collapsible railings.
[0041] [0041]FIG. 2 is a display of sample layouts of the basic modular components, illustrating various installation combinations of the present invention, also for the purposes of example only.
[0042] [0042]FIG. 3 is a side, three-quarter perspective view of one embodiment of the present invention, illustrating the principal components in three-dimensional view.
[0043] [0043]FIG. 4 is a side, partially exploded view of one embodiment of the present invention, illustrating the principal components in three-dimensional view, with means of attachment thereon.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0044] The following description refers to FIG. 1, which is a display of basic modular components of the present system including starter portion, rise members, straight members, and collapsible railings; FIG. 2, which is a display of sample layouts of the basic modular components, illustrating various installation combinations of the present invention, also for the purposes of example only; FIG. 3, which is a side, three-quarter perspective view of one embodiment of the present invention, illustrating the principal components in three-dimensional view; and FIG. 4, which is a side, partially exploded view of one embodiment of the present invention, illustrating the principal components in three-dimensional view, with means of attachment thereon.
[0045] As depicted in FIG. 2, each version of the system consists primarily of at least one start component, at least one rise component, and at least one platform or straight component, each of a size and shape selected from the components illustrated on FIG. 1. The components are constructed of wood in the preferred mode, providing an attractive and economical option for the handicapped and disabled in need of a ramp assembly.
[0046] For the purposes of example, simple pressure treated lumber may be utilized to accomplish the purposes of the invention. Thus, a particular distinction between the present invention and ramp systems of the prior art lies in the usage of such wood components in conjunction with the modular ability of the present invention. Importantly, any of these components may be of a great variety of lengths or widths, as needed for each application. Depending upon the configuration of the area to which the ramp system is temporarily installed (ie. door location, location of path, etc.), additional components besides the start, rise, and platform may be utilized.
[0047] Thus, the example shown in the top left hand corner of the FIGURE includes a 90 degree straight component, which functions to affix to a rise component on a first side and a straight component on the second side. This functions to create a generally “L” shaped configuration, when needed.
[0048] Along the same lines, the example depicted on the center left portion of the FIGURE includes a 45 degree straight component, which similarly functions to affix to a rise component on a first side and a straight component on the second side. This functions to create a generally curved configuration, when the location of the door dictates that such is required.
[0049] More elaborate embodiments are depicted in the two illustrations on the right hand side of FIG. 2, wherein the ramp system is adapted to include 6 or more components, such as 3 or more rise components with a start component, at least one platform, and 90 degree straight component, if needed.
[0050] In any case, a series of mounted brackets as a fastening means of components may be utilized. Such unique brackets are interlocking in nature and provide convenience in installation as well as sufficient space for drainage in the system.
[0051] To further illustrate the overall design, size, and possible configuration of the present invention, FIGS. 3 and 4 are side, three-dimensional views of a simple layout of the ramp system, shown for the purposes of example only. Specifically, illustrated in FIG. 3 are the start component ( 12 ), which comprises start top surface ( 12 A) and start bottom surface ( 12 B); rise component ( 14 ), which comprises rise top surface ( 14 A) and rise bottom surface ( 14 B); platform component ( 16 ), which comprises platform top surface ( 16 A) and platform bottom surface ( 16 B); collapsible railing assembly ( 18 ), which comprises horizontal members ( 18 H) and vertical members ( 18 V); and a plurality of support members ( 20 ). Illustrated in FIG. 4 are the principal components, as well as fastening means ( 22 , 24 ).
[0052] As already mentioned, the start component ( 12 ), rise component(s) ( 14 ), and platform component(s) ( 16 ) may each be of a previously determined length and width, according to what is necessary.
[0053] Railing assembly ( 18 ) includes a total of 3 horizontal members ( 18 H) in the preferred mode, but may also consist of 2 or 4 such members. A quantity of vertical members in proportion to the length of the assembly are utilized for support. Support brackets in a general “X” shape may also be utilized, functioning to provide additional support for higher vertical railing members.
[0054] Moreover, the start top surface ( 12 A), rise top surface ( 14 A), and platform top surface ( 16 A) may each comprise a non-skid material thereon, functioning to allow for increased traction for wheels and the like. The railing assembly ( 18 ) and any other components may comprise a textured, coated material thereon, functioning to protect the components from moisture and also allowing for an enhanced gripping surface for the purposes of safety. The start component ( 12 ) may also comprise an aluminum transitional member at a first end thereof, functioning to bridge any gap between a ground surface and the start component, for ease of transport of a wheelchair or the like.
[0055] Regarding any of the above embodiments, as mentioned in the Summary section herein, the entire ramp system conforms to any and all applicable ADA guidelines. Most notably, the guidelines require 1 inch or rise in pitch per every 1 foot in length of ramp utilized. The present invention adheres to such standards, rendering the system effective and safe for a host of applications and uses. Within such guidelines, the precise angle at which the components sit may be varied, if desired for a particular application.
[0056] To use a common example to further describe the above, a 3 step configuration at a height of 24 inches utilizes 2-8 foot rise members, a single 8 foot start component, plus the platform or straight component as desired. As an additional example, a total of only 2 steps at a height of 14 inches utilizes a single 6 foot start member, a single 8 foot rise component, plus the platform or straight component as desired.
[0057] It should also be noted that the size and total length of the present ramp system can vary tremendously, such as from as little as 6 feet in length, to as much as over 80 feet in length. In addition, all of the aforementioned components may further comprise a curb of a previously-determined size. For example, the preferred embodiment utilizes a 3½ inch curb.
[0058] Furthermore, the starter component of any configuration may include a closed extended rail member thereon, functioning to provide a convenient means for the user to gain support when entering the ramp area that is still very safe in nature. In addition, an inside grab rail may be included in the system, installed separately as a option for extra safety and support. In any case, the railing assembly may include a center rail which is continuous and unobstructed, so as to allow a user to use the rail for support without any impediments.
[0059] Moreover, the top rail of the ramp system of the present invention may utilize a series of interlocking components in a tongue and groove style configuration, functioning to provide additional support to the assembly. In such case, certain bracket-like support members comprise a substantially flat, rectangular member extending outwardly from an edge of the bracket, with a corresponding series of bracket-like support members comprising similarly-shaped apertures for receiving such extended members. The extended members may be constructed of a durable metal or other rigid material, and may be further reinforced through usage of traditional fasteners.
[0060] Also, in any instance the ramp system may comprise an illumination means thereon, functioning to provide additional light in the ramp area for safety and to enhance the appearance of the system. Along similar lines, the ramp system of the present invention may even include a variety of decorative elements thereon, such as attractive spindles upon the railing assembly or the like. Such will enhance the appearance of the system and provide an aesthetically pleasing item that renders the same an even more attractive option for users in need of a ramp assembly.
[0061] Therefore, in total, the versatile nature of modular components allows the ramp system of the present invention to adapt to accommodate virtually any application, the system can be literally made to order, the system is highly effective in nature yet inexpensive, the system provides ease of installation and ease of transport not provided by the prior art, and the system conforms to all safety requirements and guidelines.
[0062] With regards to all FIGURES, while the invention has been illustrated and described as embodied, it is not intended to be limited to the details shown, since it will be understood that various omissions, modifications, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing in any way from the spirit of the invention.
[0063] Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can readily adapt it for various applications without omitting features that, from the standpoint of prior art, constitute essential characteristics of the generic or specific aspects of this invention. What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.
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A portable ramp system particularly intended to assist temporarily handicapped persons with transport in and out of houses and buildings. Specifically, the system consists of several modular ramp members removably attached to one another to allow convenient wheelchair access to the application in question. Preferably constructed of wood, the members consist of hingedly-attached starter, rise, and straight panels, which may be folded down to a relatively compact size for the purpose of removal and transport. In addition, the system may include collapsible railing members to further assist the user. Finally, the horizontal panels of the ramp system may include a skid-resistant surface for the utmost in wheelchair traction. As such, the ramp system meets applicable ADA guidelines and provides a quick, convenient, and relatively inexpensive means for temporarily handicapped persons to access houses and similar structures.
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FIELD OF THE INVENTION
[0001] The present application relates to scaffold systems, and in particular, to an integrated plank and toeboard securement system.
BACKGROUND OF THE INVENTION
[0002] Scaffold safety regulations require toeboards to be used around the edge of an elevated work platform to prevent tools etc. being inadvertently dropped from a significant height. The most common scaffold systems include a toeboard arrangement that is secured to the scaffold vertical members. The toeboards can be directly secured to connectors provided on the uprights or may use specialized connectors provided on the uprights to locate the toeboards. In one system, steel toeboards are fixed in place by locating them behind wedge bracket connectors that fix the ledgers of the scaffold system to the vertical uprights. In this arrangement, the toeboard system is essentially independent of the plank system. A major disadvantage of this arrangement is that the planks defining the work platform do not always fit well on the ledgers, and there is a possibility for a gap to be present between the toeboard and the planks. Some regulations require that this gap be not greater than one inch or the scaffold may be deemed as unsafe.
[0003] It is also known in the industry to use commonly available steel channels (typically sold as metal studding) that are fixed to the scaffold vertical members by clamps or are sometimes merely wired to the vertical uprights. It is also common to use wooden toeboards that are again connected to the scaffold vertical uprights by wire or nailed to the scaffold planks.
[0004] In the UK, toeboards are often a scaffold plank that is used on edge and secured to the vertical uprights using clips or clamps, or perhaps nailing them in place.
[0005] The above prior art toeboard systems operate essentially independent from the planks as the toeboards are all secured by attaching them to the vertical posts of the scaffold.
[0006] Toeboard systems in general are considered by the industry as a necessity to meet the legal requirements, but not considered a major component of a system. For these reasons, the expense of a fully integrated toeboard system is not popular, and for cost reasons, wood or other low cost materials that are readily available are tied or otherwise secured to the uprights.
[0007] A problem exists given that scaffold frames are of a predetermined width, typically five feet in North America, and require approximately six planks to fully deck the frame. It is also known to use two 19 inch wide aluminum plywood planks if only partial decking is used. Unfortunately, with partial decking the vertical uprights are not in the appropriate location for securement of the toeboards and a further securing arrangement must be designed on site.
[0008] One system that is a major departure from the above is shown in Canadian Patent Application 2,210,952 where a toeboard system is designed for securement to an end connector of a scaffold plank. The scaffold plank system has specialized corner connectors for engaging a side rail and engaging an end cap of the scaffold plank. This corner connector includes a port for receiving a projecting securing member of a toeboard. The toeboard includes these securing members at opposite ends thereof, and are of the same length as the plank. This type of toeboard plank system has not been widely accepted in the industry. With this system, the toeboard is fixed to the securement locations at opposite ends of a scaffold plank, and the system requires dedicated planks and cooperating toeboards. For many owners of scaffolding, the additional cost and equipment cannot be justified.
[0009] The present invention seeks to overcome a number of difficulties associated with toeboard systems and provide a more cost effective solution and flexible system.
SUMMARY OF THE INVENTION
[0010] A scaffold plank according to the present invention comprises a top surface, opposed side rail portions extending the length of the plank and opposed end caps joining the side rail portions and supporting the top surface at the ends thereof. The side rail portions extend downwardly below and support the top surface along lateral edges thereof. The top surface above each rail portion includes a series of lateral securing slots intermediate the length of the plank that pass through the top surface to allow engagement with the underlying rail portion. The lateral securing slots cooperate with toeboard mounting brackets to secure a toeboard to the plank at two or more positions intermediate the length of the scaffold plank.
[0011] In a preferred aspect of the invention the lateral securing slots of the scaffold plank are elongated slots.
[0012] In a further aspect of the invention, the scaffold plank includes end securing slots provided centrally in opposed ends of the plank for cooperating with the toeboard mounting brackets to secure a toeboard to the end portion of aligned scaffold planks. Preferably, the end securing slots and the lateral securing slots are of the same configuration, and each end securing slot is provided in one of the end caps.
[0013] In yet a further aspect of the invention, the top surface and the side rail portions are integral and produced by bending of sheet material. Preferably, the end caps are of an extruded aluminum alloy or steel construction.
[0014] According to an aspect of the invention, the series of lateral securing slots include two pairs of securing slots with each pair having opposed slots positioned on opposite sides of the plank an equal first distance from an adjacent end of the plank and the end securing slot in the adjacent end of the plank is spaced from the sides of the plank the same equal first distance.
[0015] In a preferred scaffold plank, the end securing slots are spaced from lateral sides of the plank a first distance and the series of lateral securing slots include on each side of the plank lateral securing slots spaced the same first distance from adjacent ends of the plank. Preferably, the lateral securing slots on each side of the plank include a pair of securing slots adjacent a center of the plank relative to the length thereof having a shorter spacing therebetween than the spacing with the adjacent lateral securing slots.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Preferred embodiments of the invention are shown in the drawings, wherein:
[0017] FIG. 1 is a partial perspective view of a scaffold illustrating the plank and toeboard system;
[0018] FIG. 2 is a top view of FIG. 1 ;
[0019] FIG. 3 is a partial perspective view illustrating a telescopic toeboard extension;
[0020] FIG. 4 is a partial perspective of the plank and toeboard system and an intermediate plank ledger;
[0021] FIG. 5 is a perspective view of the intermediate plank ledger;
[0022] FIGS. 6 and 7 are partial perspective views of the plank system with toeboard brackets supporting wood toeboards;
[0023] FIG. 8 is a partial perspective view of the system with two different types of decking planks;
[0024] FIG. 9 is a partial perspective view of the plank and toeboard system using two different toeboards;
[0025] FIG. 10 is a perspective of a scaffold plank;
[0026] FIG. 11 is a partial perspective of a scaffold system with a sectional view through a scaffold plank;
[0027] FIG. 12 is a partial perspective view illustrating a section through two scaffold planks;
[0028] FIG. 13 is a partial perspective view of a work platform with two different types of toeboards;
[0029] FIG. 14 is a top view of the work platform of FIG. 13 ; and
[0030] FIG. 15 is a partial perspective view of a work platform.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0031] The scaffolding system 2 is partially shown in FIGS. 1 through 4 and 6 through 9 , and includes a number of uprights 4 and connected ledgers 6 to define a bay 7 having a bay length 8 and a bay width 10 . The scaffold system also includes a number of diagonal braces (not shown) connected to the rosettes 11 to brace adjacent uprights. In North America, the typical bay has a width of five feet, and a predetermined modular length of up to ten feet. Bay lengths of five and seven feet (defined by the ledgers 6 ) are also common to allow the scaffold to be adjustable to meet different physical requirements of the installation. Scaffold planks 20 are typically designed for particular bay lengths, and are designed for providing a working platform in any bay.
[0032] FIGS. 1 through 4 and FIGS. 6 and 7 show the preferred scaffold plank 20 having a top surface 22 , opposed side rail portions 24 and 26 , with end caps 28 and 30 provided at opposite ends of the scaffold plank. The end caps 28 and 30 include hooks 29 for securing the scaffold plank on opposed ledgers. In a preferred metal scaffold plank 20 (shown in FIG. 1 ) the top surface and the side rail portions are manufactured from a common sheet material to provide a ported reinforced top surface 22 and is bent to form the side rail portions 24 and 26 . Thus, the top surface is integrated with the side rail portions 24 and 26 . The end cap members 28 and 30 are typically of an extruded aluminum, or assembled from various steel or aluminum components. The end caps are inserted below the top surface 22 , and typically engage the side rails to provide a strong mechanical connection therebetween.
[0033] A series of lateral securing slots 32 are provided on one side of the scaffold plank 20 with a series 34 of lateral securing slots provided on the opposite side. As shown in FIG. 4 , each of these series of lateral securing slots include three or more slots, and in the preferred ten foot scaffold plank, include six securing slots. The scaffold plank 20 also includes an end securing slot 36 provided in one end of the plank, and an end securing slot 38 provided in the opposite end of the plank. Preferably, each of the end securing slots 36 and 38 are centrally located, and are a specific distance (a) from the sides of the plank. The first lateral securing slot (i.e. the lateral securing slot closest to an associated end securing slot) is spaced from the end of the scaffold plank of the same distance (a) (see FIG. 2 ). This arrangement allows for modularity when a toeboard is secured to the ends of the plank or to the sides of the plank. The toeboards will not be physically connected to the plank at the ends, but will be spaced a short distance either in the width of the plank or in the length of the plank. Also, the distance between lateral securing slots is preferably a multiple of this distance.
[0034] The lateral securing slots 32 and 34 are provided in the top surface of the scaffold plank and extend downwardly and allow engagement of a toeboard mounting bracket 100 with the underlying side rail portion. Preferably, the side rail portion includes a slot in its lower surface to allow a mounting bracket to pass therethrough as shown in FIGS. 3 , 7 and 8 .
[0035] One of the advantages of the scaffold plank as disclosed and shown in the drawings is the ability to provide an end support for intermediate plank ledger 50 . Intermediate plank ledger 50 includes a “U”-shaped securing member 52 that can slide along and engage a ledger 6 as shown in FIG. 4 . The intermediate plank ledger also includes a tube portion 54 with the plank engaging hook 56 at one end thereof. With this arrangement, the intermediate plank ledger is connected to a ledger 6 using the U-shaped connector 52 , and is rotated downwardly and can be moved along the ledger such that the plank engaging hook 56 is located for engaging one of the securing ports in a side of the plank. In this way, an intermediate support for a shorter plank can be provided in any bay to accommodate an upright structure that is passing through the scaffold. For example, a series of pipes or a column support for a building may require the scaffold to be built around this structure. Shorter scaffold planks 20 a (see FIG. 6 ) can be used and the end securing slots allow for securement of a toeboard. Similarly, a toeboard 79 can be provided as shown at 80 on the partial length of the longer plank 20 b . Thus a toeboard can easily be provided around the perimeter of an upright portion that is extending through the scaffold.
[0036] Various arrangements for toeboards are shown in the drawings. In the preferred embodiment ( FIGS. 1 through 3 ), the toeboards 108 are of a fabricated metal construction having a central portion 110 and two flat end portions 112 . Each of these end portions include a securing slot 114 for engaging a like toeboard in a perpendicular interlocking arrangement as shown in FIG. 1 . If the toeboards are used in an end to end manner, these connecting portions effectively overlap and also partially engage to avoid tools being inadvertently dropped. Thus, the toeboards allow effective overlap of members 112 at adjacent ends.
[0037] A number of mounting brackets 300 are also shown, where the mounting brackets allow a contractor to use existing materials for forming toeboard systems. The mounting brackets 300 include a male component 302 for non-rotatably engaging any of the securing slots ( 32 , 34 , 36 , 38 ) either lateral or in the end portion, and typically these brackets include a “U”-shaped slot for receiving a toeboard such as a wooden toeboard or a metal channel. These materials are commonly available on site and the brackets allow effective use of these common materials. Contractors often prefer to merely fabricate toeboards onsite rather than purchase a system of toeboards. The mounting brackets 300 when received in a plank automatically align the “U”-shaped slot for receiving a toeboard. This arrangement simplifies installation.
[0038] Contractor fabricated toeboards are shown in FIGS. 6 , 7 and 8 . FIG. 9 shows a wooden toeboard 308 and a metal contractor fabricated toeboard 310 both secured by brackets. FIG. 8 illustrates the toeboard and plank system using two different types of planks. One bay has planks 20 whereas the adjacent bay shows a wider (19 inch) plywood deck 331 also having the securing ports 320 and 322 in the ends of the deck and securing ports 324 provided in siderails 330 .
[0039] In the system toeboards of FIGS. 8 and 9 , the toeboard 250 includes a series of downwardly extending male projections 262 that are positioned for engaging the lateral securing slots or the end securing slots in aligned scaffold planks. The toeboards are easily dropped in position for securing of the toeboard about the periphery of a bay as required and for cooperation with adjacent bays.
[0040] The following features of the toeboard and scaffold plank can be appreciated from a review of the drawings.
1) The toeboards are secured to the planks and not the vertical posts of the scaffold. With this arrangement the width of the planking can vary relative to the width of the scaffold bay and the toeboards can be appropriately secured to protect the exposed edges of the working platforms. 2) System toeboards can be used and the system toeboards accommodate the use of an inner sliding channel in order to allow the system to accommodate make-up bays. The inner sliding channels are available in pre-determined lengths and can be used elsewhere as system toeboards located and fixed to the planks using drop-in securing brackets. 3) The system is designed for use with a pre-engineered toeboard system, a knock-down system or by fabrication on site. This knock down system can be made from pre-engineered steel “C”-channels and brackets, or even wooden toeboards that are fixed to the planks using the same brackets as those that fix the steel channels. No such mix and match solution has been offered before. 4) The planks have slots in pre-determined positions. These slots occur at each end of the plank and also close to the ends on the longitudinal upper edges of the planks. These slots accommodate the tongues of the system toeboard units, or brackets. They may also be used to fix other decking accessories. No other system has introduced planks that provide fixing slots at predetermined modular positions. 5) The slots along the length of the plank are in predetermined positions and allow the attachment and location of an intermediate plank support. This member spans between the outer plank and the outer longitudinal ledger of the scaffold frame work. Because the slots are located 5 feet, 7 feet or other modular lengths from either end of the plank, system planks can be used that have one end supported by the intermediate plank support and the other by the scaffold framework. Though intermediate supports are often used in the scaffold business, they are not located in position, nor retained by slots in the plank system. 6) Because the toeboards are not attached to the scaffold framework, openings in the middle of platforms (that are not close to any vertical scaffold members) can be surrounded by toeboards and are rendered much safer because there are a multitude of slots in the plank system. It is highly likely that every edge of any such opening, in the scaffold platform, would have at least two slots to fix system toeboards of the knock-down toeboard brackets into them. 7) Where wood toeboards have been chosen, due to cost or convenience, the users can fit the toeboard brackets into the slots in the planks almost anywhere. This means that almost any length of wood could be used. This avoids lapping and wiring. 8) Like other system solutions, the toeboard units can be used longitudinally and at the ends of scaffolds. 9) The slots in the planks could also be used as a bottom connection for a single guardrail that has an integral toeboard unit. The top part would be secured to the scaffold posts and the bottom retained by the slots in the planks. Of course, this solution would rely on the close proximity of the outer planks to the vertical posts of the scaffold. 10) The slots at the side and ends of the planks also provide fixing points for infill plates that cover any gaps at the end and between planks. No such fixing has hitherto been possible. 11) Aluminum and plywood decks are also available with slots that are located at the same position as the steel planks. The aluminum side rail has been specifically designed so that the slots do not interfere with the decking along the length, the end slots do pass through the decking member, whether this is steel plate or plywood. 12) In order for the toeboard system to work efficiently, the decks or planks are aligned and the hooks on the planks are designed to mesh together and maintain the alignment of each plank longitudinally. Laterally, the ledger heads at each end of the scaffold system retain the planks in this direction, although this is only necessary where end toeboards are fitted to the platform. 13) The locating tongues, on the system toeboard units, are tapered where they pass through the slots in the plank. This taper enables the toeboard to be lifted upwards to allow the fitting of the last toeboard of a square platform, that is totally bordered by toeboards.
[0054] With the present system, a unique scaffold plank has been disclosed that provides securing slots (either lateral along the edges of the securing plank, or in the end portions of the securing plank) which allow toeboards to be effectively secured at positions spaced from end corners of the plank. The series of lateral securing slots are provided at different points in the length of plank and also cooperate with a plank support tube that is slidable along a ledger and can be positioned for engaging in one of these ports. This provides a simplified arrangement for convenient support of planks which do not extend the full length or width of a bay.
[0055] Although various preferred embodiments of the present invention have been described herein in detail, it will be appreciated by those skilled in the art, that variations may be made thereto without departing from the scope of the appended claims.
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A scaffold plank and toeboard system provides a fully integrated system where toeboards are easily securable to provide perimeter protection about different working platform configurations. The scaffold advantageously includes a series of securing ports that allow male connectors of the system toeboards, or male connectors of generic toeboard securing brackets to be appropriately placed for maintaining wooden, metal or other toeboard material that is basically fabricated onsite according to the material available. The scaffold securing plank also cooperates with other equipment, guard rails, plank support intermediary ledgers etc. to use the securing ports to simplify installation and securement thereof.
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FIELD OF THE INVENTION
This invention involves the discovery of novel 2-substituted 7-haloindenes useful in coupling reactions to produce a wide variety of metallocene catalyst intermediates.
BACKGROUND OF THE INVENTION
Metallocenes which comprise indene systems are well known α-olefin polymerization catalysts. Substitution patterns in such indene systems significantly influence poly-α-olefin properties, including tacticity and molecular weight.
Spaleck, et al., Organometallics (1994) 13:954-963 describes bridged zirconocene catalysts including indene systems illustrated by Compound 4 of "Scheme 1" (p. 955) which yield highly isotactic polypropylene when used with methylaluminoxane as a cocatalyst. As shown by "Scheme 2", Compound 10, Spaleck's synthesis requires an expensive 2-(bromomethyl) biphenyl starting material.
This invention provides a more cost effective synthesis of metallocene catalysts which comprise indene systems.
SUMMARY OF THE INVENTION
One aspect of this invention provides novel 2-substituted, 7-haloindenes of Formula I: ##STR1## in which R is any straight or branched chain alkyl group having 1 to 10 carbon atoms, and X is a halogen, i.e., fluorine, chlorine, bromine or iodine. A preferred embodiment of this aspect of the invention is 2-methyl-7-chloroindene.
Another aspect of the invention includes coupling of Formula I indenes with a Grignard reagent having the formula ArMgX to produce the novel compounds of Formula II: ##STR2## in which Ar may be any aryl group. Formula II compounds in which Ar is a phenyl, e.g., Spaleck's compounds 13a and 13b, or a naphthyl group are useful for the synthesis of the zirconocene olefin polymerization catalysts of Spaleck's "Scheme 1". See Spaleck compounds 7a, 7b, 7c, 8 and 9.
The invention accordingly comprises the novel Formula I and II compounds per se, procedures for the synthesis thereof, procedures for the conversion of Formula II compounds to catalyst intermediates, including Spaleck's compounds 13a and 13b, for the production of metallocene catalysts from such intermediates and for the use of such catalysts to polymerize, e.g., an α-olefin.
DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a scheme for the synthesis of the Formula I compound, 2-methyl-7-chloroindene.
FIG. 2 is a NMR spectrum of 2-methyl-7-chloroindene produced by the FIG. 2 scheme as shown by Example 1.
FIG. 3 illustrates a scheme for the synthesis of the Formula I compound, 2-ethyl-7-chloroindene.
FIG. 4 illustrates a scheme for Grignard reagent coupling a Formula I compound to provide a Formula II compound.
DETAILED DESCRIPTION OF THE INVENTION
PREPARATION OF FORMULA I COMPOUNDS
Either of two methods, as shown by Examples 1 and 2 and FIGS. 1 and 3, may be used to prepare Formula I compounds.
THE EXAMPLE 1 METHOD
The starting material for the Example 1 method is a malonic acid diester having the Formula III: ##STR3## in which R 1 (which is the same R 1 as in the Formula I and II compounds), R 2 and R 3 are the same or optionally different straight or branched chain alkyl groups having 1 to 10 carbon atoms. Alkyl groups specifically useful in this aspect of the invention include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, isopentyl, heptyl, isoheptyl, octyl, isooctyl, nonyl, isononyl, decyl and isodecyl groups. A preferred diester is methyl diethyl malonate in which R is methyl and R 2 and R 3 are ethyl.
The malonic acid diester of Formula III is reacted with an alkali metal hydride ZH, in which Z is lithium, sodium or potassium, to provide an intermediate compound in which the "H" of the Formula III diester is replaced by Z+, e.g., Na+. This reaction is appropriately carried out by adding a 40% to 60% dispersion of an alkali metal hydride in mineral oil to a non-interfering solvent such as tetrahydrofuran (THF) in a reaction vessel positioned in an ice bath. The malonic diester is added slowly while the temperature is maintained below 10° C. Hydrogen evolution is monitored. Upon completion of the addition of the diester, the reaction vessel is removed from the ice bath, and the reaction mixture containing the intermediate compound is stirred, e.g., for about 1 to 4 hours, preferably about 2 hours.
When the addition is complete, the reaction mixture containing the intermediate compound is cooled to a temperature of 0° C. to 10° C., preferably 5° C., and a 2-halobenzylhalide, preferably a 2-chloro or 2-bromobenzyl halide, is added over a time period of 0.5 to 1.5 hours to provide a reaction mixture containing a Formula IV compound. This reaction mixture is stirred, preferably at about ambient temperature, for 6 to 15, preferably about 12, hours: ##STR4## in which X is the halogen substituent, preferably chlorine, of the Formula I compound. The Formula IV diester is saponified by heating. The reaction mixture containing the diester is heated and combined with 30% to 60% aqueous alkali metal hydroxide, preferably NaOH, to provide a compound having Formula V: ##STR5## in which Z is an alkali metal.
THF and the alcohols R 2 OH and R 3 OH, which result from saponification of the diester IV, are removed by distillation. The saponification reaction mixture is cooled, and poured into aqueous acid, e.g., 4-6N HCl, with vigorous stirring to produce a compound having Formula VI: ##STR6## The white solids comprising the Formula VI compound which form are removed by filtration, dried and placed in an appropriate reaction vessel equipped for short path distillation. Heating is applied to melt the solids and thereafter increased to 120° C. to 150° C. for a period of about 0.5 to 1.5 hours to accomplish decarboxylation and produce a compound of Formula VII: ##STR7##
The melt so produced is cooled to about 50° C., dissolved in a non-interfering solvent, e.g., an aliphatic hydrocarbon solvent having 6 to 9 carbon atoms, preferably heptane, and the Formula VII compound present in the solution is reacted with SOCl 2 at a temperature of 40° to 60° C. with stirring to produce a Formula VIII compound: ##STR8##
The temperature of the reaction mixture is thereafter raised to 100° C. to 130° C. to remove excess SOCl 2 and solvent. The reaction mixture is then cooled to room temperature, a chlorinated hydrocarbon solvent, preferably methylene chloride, is added, and the mixture is cooled to -10° C. to 0° C., followed by the addition of aluminum chloride with stirring to produce a compound of Formula IX by Friedel-Craft acylation: ##STR9##
The acylation reaction is quenched by pouring on to ice. The layers which form are separated, and organic layer washed with an aqueous base, preferably sodium bicarbonate. All solvent is removed by distillation, methanol is added, and the reaction mixture containing Formula IX is cooled in an ice bath and combined with sodium borohydride to produce Formula X: ##STR10##
The reaction is quenched with water, and methylene chloride is added to separate the Formula X compound, and the solvent is removed by distillation. The Formula X compound is reacted with paratoluene sulfonic acid (PTSA) in toluene (or other aromatic solvent such as xylene or mesitylene) to afford the desired 2-substituted, 7-haloindene, compound of Formula I: ##STR11##
Aqueous and organic layers separate upon addition of aqueous sodium bicarbonate. The organic layer is dried over anhydrous Na 2 SO 4 . Toluene is removed by distillation.
Example 1
Synthesis of 2-Methyl-7-Chloroindene
This example illustrates the scheme depicted by FIG. 1.
A 5 L round-bottom flask is equipped with a mechanical stirrer, thermometer and reflux condenser, and swept thoroughly with nitrogen. 2 L tetrahydrofuran (THF) is added to the flask and then 116 g NaH, 60% dispersion in mineral oil (2.9 mol). An ice bath is applied to the flask and moderate stirring begun. 506 g methyl diethyl malonate (2.9 mol) is added slowly from an addition funnel maintaining the temperature below 10° C. Hydrogen evolution is monitored and vented through a mineral oil bubbler and controlled by the rate of addition of the methyl dimethyl malonate. Once the addition is complete, the cooling bath is removed, and the reaction stirred for 2 hours. The flask is again cooled to 5° C. and 367 mL 2-chlorobenzylchloride (2.9 mol) added over 1 hour, then stirred for 12 hours at ambient temperature. Reflux condenser is changed to short path distillation. 520 mL 50% W/v NaOH(aq) and 1500 mL H 2 O is added, then heating begun to distill the THF. Distillation was continued to 100° C. with additional water to keep the reaction clear and fluid. Distillation was continued to remove ethanol and water at 100° C. for 15-30 minutes. Once cooled, the reaction mixture was poured into 1.5 L H 2 O and 1 L 12N HCl with vigorous stirring. White solids, which formed immediately, were collected by filtration and dried on the Buchner funnel by aspiration for 15 minutes, then returned to the 5 L flask equipped for short path distillation. Heating was applied slowly to melt the solids, and then increased to 135° C. for at least 1 hour. CO 2 evolution was monitored by venting through a mineral oil bubbler. The melt was cooled to 50° C. and 2 L heptane added, then warmed to 45° C., and addition of 265 mL SOCl 2 (3.63 mol) was begun. Adequate venting was provided. After all the SOCl 2 was added, the reaction was stirred for 1.5 hours at 60° C., then heated to 120° C. to distill the excess SOCl 2 and all the heptane. The reaction flask was allowed to cool to ambient temperature and 1.5 L CH 2 Cl 2 is added. Cooling was applied to -5°-0° C., and 465 g AlCl 3 (3.5 mol) added in portions. The reaction was stirred at ambient temperature for 2 hours, then quenched by pouring onto 2 Kg ice. The layers were separated, and the organic layer was washed with 500 mL H 2 O, and then 250 mL 5% w/v NaHCO 3 (aq). All the solvent was distilled to a temperature of 70° C. 1 L methanol was added to the oil, the flask cooled with an ice bath, and a slurry of 56 g NaBH 4 (1.5 mol) in 500 mL methanol containing 1 g NaOCH 3 was slowly added. Hydrogen evolution was monitored by venting through a mineral oil bubbler and controlled by the rate of addition. The reaction was quenched by adding 1.5 L H 2 O and 500 mL CH 2 Cl 2 to separate the product. Solvent was distilled from the separated organic layer up to 70° C. 1.5 L toluene was added to the oil and the 5 L flask equipped with a Dean-Stark trap. Heating was begun and p-toluene sulfonic acid was added in 1-3 g portions. The reaction was followed by GC until the dehydration was complete. 1.5 L 5% w/v NaHCO 3 (aq) was added to the reaction, the layers separated, and the organic layer dried over anhydrous Na 2 SO 4 . Toluene was distilled under reduced pressure to 90° C. and the product, 2-methyl-7-chloroindene, obtained by distillation thorough a 30 cm packed column at 93°-5° C. at 1-3 mm Hg. Yield was 310 g (1.89 mol), 65%, of a clear, colorless oil b.p. 229° C. FIG. 2 was the NMR spectrum of the product.
THE EXAMPLE 2 METHOD
The starting material for the Example 2 method for producing Formula I compounds is an alkali metal, preferably sodium, salt of a fatty acid, e.g., butanoic acid, having the Formula R 1 COOZ (XI) in which R 4 is a 1 to 9 carbon atom straight or branched chain alkyl group as previously described and Z is an alkali metal.
This Formula XI acid is reacted in THF solution with an alkali metal, preferably lithium diisopropylamide, to form the intermediate XII: ##STR12## in which Z is an alkali metal, preferably sodium, and Z 1 is an alkali metal, preferably lithium.
The Formula XII compound is reacted with a 2-halobenzylhalide to provide Formula XIII compound: ##STR13## in which X is a halogen, preferably chlorine or bromine, i.e., the halogen of a Formula I compound.
More specifically, this series of reactions may be carried out by combining an alkali salt of a fatty acid having 2 to 10 carbon atoms with an alkali metal, preferably lithium diisopropylamide to produce a compound having the Formula XII in THF solution. The reaction is conducted at ambient temperature and preferably stirred for 24 hours. 2-halo benzylhalide is added to the reaction mixture so produced, and the reaction mixture stirred for an additional time period, preferably 18 to 24 hours. The reaction is then quenched, e.g., by the addition of water. The aqueous layer is neutralized by a mineral acid, e.g., hydrochloric acid, at which point a phase separation occurs. A 2-halobenzyl fatty acid, such as the compound of Formula XIII, is concentrated in the organic layer.
Synthesis of 2-ethyl-7-chloroindene is completed by the same sequence of reactions as described in Example 1 and shown in FIG. 3, beginning with the addition of SOCl 2 .
Example 2
Synthesis of 2-Ethyl-7-Chloroindene
This example illustrates the scheme depicted by FIG. 3.
A 12 L round-bottom flask was equipped with a mechanical stirrer, thermometer and reflux condenser. 385 g sodium butanoate (3.5 mol) and 2 L THF were added to form a slurry. 2.625 L lithium diisopropylamide, 2M in heptane/THF/ethylbenzene (5.25 mol, 50% excess) were added at ambient temperature, and then stirred for 24 hours. Then 705 g 2-chlorobenzyl chloride (4.375 mol, 25% excess) was added, and the reaction stirred for another 24 hours. Once completed, the reaction was quenched by adding 1500 mL H 2 O, and the solution allowed to separate. The aqueous layer, pH=13, was separated and neutralized by addition of 12N HCl to obtain pH=7.0, at which point a phase separation occurs. 2-(2-chlorobenzyl) butanoic acid was concentrated in the organic layer. Synthesis of 2-ethyl-7-chloroindene was completed by the same sequence of reactions and method as described in Example 1, beginning with the addition of SOCl 2 . See FIGS. 1 and 3. The product, 2-ethyl-7-chloroindene, was obtained by distillation at 110°-114° C. under 1-3 mm Hg. Yield was 205 g (33% overall) of a clear, colorless oil.
PREPARATION OF FORMULA II COMPOUNDS
As shown by FIG. 4, Formula II compounds are prepared in known manner by reacting a Formula I compound with a Grignard reagent, ArMgX, in which X is Cl, Br or I, Ar is any aryl group, for example, a phenyl or naphthyl group, in an ethyl ether solvent containing 1-3-bis(diphenylphosphino) propane nickel II chloride, Ni(dpp).
Examples 3-6 utilize the synthesis of the Formula II compounds depicted by FIG. 4.
Example 3
A 5 L round bottom flask was equipped with mechanical stirring, a reflux condenser and ice bath. 488.2 g distilled 7-chloro-2-methylindene (2.97 mol) was added, dissolved in 2 L ether and 32.2 g Ni(dpp) (0.059 mol, 2 mol %) slurried in the solution, and stirred to cool to 0°-2° C. 1.05 L of 3.1M phenylmagnesium bromide in ether (3.25 mol, 10% excess) was added slowly from an addition funnel so that the temperature remained below 5° C. Once complete, the ice bath was removed, and the reaction stirred up to room temperature. The reaction was refluxed for 8 hours, and checked for completion by GC. The reaction flask was cooled with an ice bath, and 250 mL water added, then 1 L 10% HCl. The aqueous and organic layers are separated, and the organic layer dried over anhydrous Na 2 SO 4 . Ether was distilled, and the residual oil placed on a column of 100 g silica gel. Elution with hexane was performed, the hexane distilled under reduced pressure to a temperature of 90° C. 2-methyl-7-phenylindene (Spaleck compound 13a) was obtained by distillation at <1 mm Hg with a 36 cm Vigreux column at 125° C. A fore-cut containing biphenyl was obtained at 70°-90° C. and discarded. Yield was 507.8 g (2.47 mol) equal to 80%.
Example 4
A 12 L flask equipped as in Example 3 was charged with 661 g distilled 2-methyl-7-chloroindene (4 mol), 2.5 L ether, and 43.3 g Ni(dpp) (0.08 mol, 2 mol %). 1.75 L of 2.6M phenylmagnesium bromide in ether (4.55 mol, 12% excess) was added at 2° C. Following stir-out to ambient temperature and reflux for 8 hours, the reaction was quenched and worked up by the method described in Example 3. Yield of 2-methyl-7-phenylindene was 642.7 g (3.12 mol) equal to 78%.
Example 5
A 5 L flask was equipped as in Example 3.178 g 2-ethyl-7-chloroindene (1 mol %), 1 L ether and 10.8 g Ni(dpp) (0.02 mol, 2 mol %) added, followed by 355 mL of 3.1M phenylmagnesium bromide in either (1.1 mol, 10% excess). After quenching and work-up by the method described in Example 3, 176 g 2-ethyl-7-phenylindene (0.8 mol) was obtained by vacuum distillation at 140° C. in 80% yield.
Example 6
A 5 L flask was equipped as described in Example 3. 164 g 2-methyl-7-chloroindene (1 mol) 500 mL ether and 10.8 g Ni(dpp) added. 2 L of 0.5M naphthylmagnesium bromide in ether was added at 20° C. The reaction was stirred vigorously at reflux for 12 hours, then quenched and worked up as described in Example 3. 184.3 g 2-methyl-7-(1-naphthyl)-indene (Spaleck compound 21) (0.72 mol) was obtained by recrystallization from heptane in 72% yield.
METALLOCENE CATALYSTS
The Formula II compounds of this invention may be converted to metallocene α-olefin polymerization catalysts in the manner illustrated by Spaleck's Schemes 1 and 2. Polymerization procedures utilizing such catalysts are exemplified by spaleck at page 963.
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Novel 2-substituted 7-haloindenes and methods for synthesizing such indenes are described. The 2-substituted 7-haloindenes may be coupled with any aryl group to produce a metallocene catalyst intermediate.
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates to a transmission with a steplessly adjustable transmission ratio with an endless torque-transmitting means, particularly for transmitting power between two pairs of conical disks of the transmission.
[0003] 2. Description of the Related Art
[0004] FIG. 1 shows a side view of an endless torque-transmitting means in the form of a chain, as is known from DE 199 22 827 A1. The endless torque-transmitting means is assembled from plate links 10 a , 10 b several of which, not visible in FIG. 1 , are arranged in longitudinal rows in the length direction of the endless torque-transmitting means. The plate links have openings 12 through which pressure members 12 grippingly extend by means of which the plate links are assembled and joined together in a longitudinal and transverse connection to form the endless torque-transmitting means. Opening 12 of each plate link is penetrated by two pressure members 14 that are supported on the forward and rear walls of the opening, whereby at least single ones of the plate links 10 a , 10 b that are in different longitudinal rows of plate links in the longitudinal direction of the endless torque-transmitting means are displaceably arranged in a longitudinal dimension of an opening less the pressure member diameter, so that a pressure member that extends transversely through the endless torque-transmitting means and projects therethrough is supported on one end side of the openings and another of the pressure members on the other end side, through which the transmission of longitudinal forces within the endless torque-transmitting means is made possible.
[0005] The end surfaces 16 on the sides of the pressure members are designed for frictional engagement with associated conical surfaces of conical disk pairs (not shown), between which the endless torque-transmitting means transmits forces or torques.
[0006] The pressure members 14 are in each case subdivided into two rocker members that roll against each other by chain articulation movements of the plate links and thereby minimize the friction on the plate links of the link structure. To connect the pressure members in a secure manner with the plate links 10 , formations in the form of weld points are applied to the outer periphery of the pressure members 14 .
[0007] An endless torque-transmitting means in accordance with FIG. 1 is generally constructed in such a way that the arrangement of the individual plate links that are aligned relative to each other in the transverse direction of the endless torque-transmitting means are periodically repeated in individual longitudinal rows, for example the second transverse row that is offset relative to the first transverse row is arranged differently than the third transverse row that is in turn offset relative to the second transverse row, to which, in turn, the first transverse row follows. One refers then to a three-link connection.
[0008] The arrangement of the individual plate links within the longitudinal rows and the transverse rows has a marked influence on the operating behavior of the endless torque-transmitting means, such as its endurance, its abrasion, and the like.
[0009] An object of the invention is to develop a generic transmission with an endless torque-transmitting means of such a type that the forces that appear within the plate links in the interconnection of the endless torque-transmitting means or plate-link chain, and therewith the stress on the plate links and on the pressure members, is as uniform as possible.
SUMMARY OF THE INVENTION
[0010] The object is achieved in that in accordance with the invention in each case in the outermost region of the chain two or more immediately adjacently arranged plate links carry the uniformly divided forces, especially in the highly-loaded outer marginal region of the endless torque-transmitting means, by means of the double plate links or paired plate links provided there. In the middle region of such an endless torque-transmitting means in accordance with the invention there can be provided in individual transverse rows only individual plate links.
[0011] Furthermore, it is advantageous that the endless torque-transmitting means in accordance with the invention, as is known, can be formed as a triple connection. It should be understood that also other connections are possible.
[0012] Moreover, in each case there can be arranged on the outside more than two plate links immediately next to each other.
[0013] It is furthermore advantageous, at a position inside the outermost aligned plate links that are immediately adjacently arranged, to arrange a large number of immediately adjacently arranged offset plate links.
[0014] The number of plate links that are seen in the transverse direction of the endless torque-transmitting means with their openings aligned relative to each other and arranged behind each other can be uniform, and that number can in other exemplary embodiments be different in the longitudinal direction of the endless torque-transmitting means.
[0015] Furthermore, the arrangement of the plate links relative to the longitudinal centerline of the endless torque-transmitting means can be symmetrical or unsymmetrical.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention will be further explained below by examples and with further details on the basis of schematic drawings in which there is shown:
[0017] FIG. 1 a side view of an endless torque-transmitting means formed as a plate-link chain,
[0018] FIG. 2 a top view of a section of an endless torque-transmitting means,
[0019] FIG. 3 two sections in accordance with FIG. 2 joined together,
[0020] FIG. 4 a top view of a section of a plate-link chain that is modified relative to FIG. 2 ,
[0021] FIG. 5 a top view of a section of a further embodiment of a plate-link chain,
[0022] FIG. 6 a top view of a section of a further modified embodiment of a plate-link chain,
[0023] FIG. 7 a top view of a section of a further modified embodiment of a plate-link chain,
[0024] FIG. 8 a force curve across the width of a plate-link chain,
[0025] FIGS. 9 and 10 a top view of a section of two further modified embodiments of a plate-link chain.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] FIG. 2 shows a top view of a section of a plate-link chain whose plate links 10 are arranged in forty-one side-by-side, longitudinal rows extending in the longitudinal direction of the plate-link chain (vertical direction of the paper). The plate-link chain is assembled from three different transverse rows A, B, and C, within which in each case two pressure members 14 intervene to provide a connection between each two transverse rows. The transverse rows A, B, and C are each offset from each other in the longitudinal extent of the openings 12 ( FIG. 1 ), less the diameters of the pressure members 14 .
[0027] As can be seen from FIG. 2 , the plate links in the different transverse rows in the transverse direction of the plate-link chain are arranged in such a way that viewed from left to right first of all two outermost plate links are arranged in transverse row B, then follow two plate links in transverse row A, then follow four plate links in transverse row C, then follow two plate links in transverse row A, then follow four rows in transverse row B, then follow two plate links in transverse row A, two plate links in transverse row C, two plate links in transverse row A, two plate links in transverse row B, one plate link in transverse row C, two plate links in transverse row A, two plate links in transverse row C, two plate links in transverse row B, two plate links in transverse row C, two plate links in transverse row A, four plate links in transverse row B, two plate links in transverse row A, and two plate links in transverse row C. Transverse row A contains fourteen plate links, transverse row B likewise contains fourteen plate links, and transverse row C contains 13 plate links, that in the described way divide into longitudinal rows 1 to 41 .
[0028] FIG. 3 shows two sections of FIG. 2 placed together to show that the pattern of FIG. 2 is in each case repeated.
[0029] Whereas in FIG. 1 , which shows a side view of a known plate-link chain, from the outside the outermost plate links of all three transverse rows are visible, in the plate-link chain with an interconnection in accordance with FIG. 2 from the left only the outermost plate links of transverse rows B and A are visible.
[0030] FIG. 4 shows an arrangement of plate links of a plate-link chain that is different from the arrangement in accordance with FIG. 2 , in that the longitudinal rows 28 to 37 are filled differently.
[0031] FIGS. 5 to 7 show views of sections of a plate-link chain that are composed of only 36 longitudinal rows. On the other hand, the outermost plate links are each arranged in side-by-side immediate pairs, whereby those plate links are in each case arranged in transverse row B. The pattern of FIGS. 5 and 6 is symmetrically related on the longitudinal centerline, wherein in each transverse row twelve plate links are arranged.
[0032] The embodiment of the plate-link chain in accordance with FIG. 7 is unsymmetrical relative to the longitudinal central plane of the plate-link chain, wherein there are twelve plate links arranged in transverse row A, eleven plate links in transverse row B, and thirteen plate links in transverse row C.
[0033] As is immediately apparent from the figures, the illustrated embodiments of plate-link chains in accordance with the invention are common in that each of the outermost plate links (in transverse rows B and C in accordance with FIGS. 2 and 4 ) and in the transverse row B in accordance with FIG. 5 to 7 are in each case arranged in pairs immediately next to each other. In the interior there follows in each case a further plate-link pair, as to which further to the inside in a transverse row a number greater than two immediately adjacently arranged plate links are connected.
[0034] FIG. 8 shows the operating plate-link loads K within the plate-link chain as a function of the width position B in the plate-link chain. The continuous curve k shows the load distribution in conventional plate-link chains. The dashed curve e shows the load distribution in plate-link chains in accordance with the invention. As can be seen, the differences between the operating loads in the outer regions relative to the loads in the inner region of the plate-link chain are clearly diminished by the arrangement of the plate links in accordance with the invention.
[0035] FIG. 2 shows a top view of a section of a plate-link chain whose plate links 10 are arranged in 41 side-by-side-arranged longitudinal rows in the longitudinal direction of the plate-link chain (vertical paper direction). The plate-link chain is assembled from three different transverse rows, within which in each case two pressure members 14 establish a connection between each two transverse rows. Transverse rows A, B, and C are in each case offset relative to each other in the longitudinal extent of openings 12 ( FIG. 1 ) less the diameter of pressure members 14 .
[0036] As can be seen from FIG. 2 , in the transverse direction of the plate-link chain the arrangement of the plate links in the different transverse rows is such that viewed from left to right first of all two outermost plate links are in transverse row B, then follow two plate links in transverse row A, then follow three plate links in transverse row C. Then follows a plate link in each of transverse rows B, C, A, C, B. Thereafter follows a further single plate-link connection on rows B, C, B, A, B, C. The following plate link 101 of row A is the central axis of the chain. The chain pattern of the second half of the chain is the mirror image.
[0037] FIG. 10 likewise shows a symmetrical plate link connection with thirty rows of plate links linked together in rows A, B, C in the transverse direction. Both plate links 201 arranged in row B thereby form the plane of symmetry, from there outward the plate links are arranged as follows to edge position 1 or 30 : plate link 201 followed by individual plate links in rows A, B, A, two plate links in row B, a single plate link in row A, four plate links in row C, two plate links in row A, and two plate links in row B.
[0038] The claims that are filed in the application are formulation proposals without prejudice for the obtaining of broader patent protection. The applicant reserves the right to claim still further combinations of features that, at this time, are disclosed only in the specification and/or in the drawings.
[0039] The references made in dependent claims point out further developments of the matter of the main claim through the features of the respective dependent claims; they are not to be understood to constitute a waiver of the achievement of an independent objective protection for the combinations of features of dependent claims that refer to preceding claims.
[0040] Since the features of dependent claims, as far as the state of the prior art on the priority date is concerned, can constitute separate and independent inventions, applicant reserves the right to recite the subject matter of such dependent claims in independent claims or in divisional applications. Furthermore, such dependent claims can recite independent inventions embodying structure other than that in the parent dependent claims.
[0041] The exemplary embodiments should not be interpreted as a limitation of the invention. On the contrary, within the scope of the present disclosure numerous changes and modifications are possible, especially such modifications, elements and combinations and/or materials that, for example, as a result of combinations or modifications of individual features or elements or method steps contained in the general description, in the descriptions of various embodiments, and in the claims, and illustrated in the drawing, can be comprehended by persons skilled in the art as far as the achievement of the object is concerned and, as a result of combinable features, lead to a novel device or to novel method steps and/or sequences of method steps, also as far as the manufacture, testing and mode of operation are concerned.
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A transmission having a steplessly adjustable transmission ratio that includes an endless torque-transmitting element in the form of a plate-link chain. The chain is adapted to pass over and around two pairs of conical disks, and it includes a number of side-by-side plate links having openings for receiving pressure members that interconnect plate links and that have end faces that frictionally engage the conical disks. The plate links are arranged in transverse rows and in longitudinal rows. Each of the outermost lateral edges of the chain is defined by pairs of side-by-side plate links.
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This application is a 371 of PCT/FR99/01071 filed 6 May 1999.
FIELD OF THE INVENTION
The invention concerns a process for producing paper pulp, lignins, sugars and acetic acid from lignocellulosic plant material constituting the essential part of annual and perennial plants.
From now on, an annual plant is understood to be any plant having a vegetative life of the order of one year (cereals, various grasses, cotton, hemp, flax, sorghum, sugar cane, reeds, etc.) and a perennial plant is understood to mean a plant of which the development extends over a longer period (bamboos, broad-leafed wood, resinous wood, etc.).
The lignocellulosic materials of the invention are whole plants or parts of these plants (stems, bark, etc.) or co-products from industrial processes aimed at the production of foods, (wheat straw, rice, barley; sugar cane bagasse, sugar sorghum bagasse, etc.).
Paper pulps produced from annual or perennial plants may be classified according to the technology used, their paper-making quality and the mass yield obtained relative to the initial plant material.
The paper-making quality of a pulp is defined in relation to the process for separating cellulosic fibres or defibration and relative to a series of physico-chemical parameters of which the most important are the breaking length which relates to the tensile strength, the tear index and the burst index. The higher these properties, the better will be the quality of the pulp produced.
The following are thus considered:
so-called mechanical or thermomechanical low-quality pulps, which are obtained with a yield of the order of 80 to 90% by mechanical or thermomechanical processes, chemicothermomechanical pulps or semi-chemical pulps of medium quality, which are obtained with a yield of the order of 60 to 80% by chemicothermomechanical or semi-chemical processes, superior quality chemical pulps which are obtained with a yield of the order of 40 to 50% by chemical processes.
In the case of annual plants, the particular nature of the lignocellulosic material does not always allow suitable values for the breaking length (greater than 4000 meters) to be obtained, even with chemical processes.
It should be recalled that the breaking length, an essential characteristic of paper pulp and paper corresponds to the length of a uniform strip of any width assumed to be suspended by one of its ends breaking under the effect of its own weight. This breaking length is calculated by the formula 106×RT/15 G·g in which:
RT is the tensile breaking strength expressed in newton per meter (NF standard Q 03 002) G is the grammage of the paper strip expressed in g/m 2 . g is the acceleration due to gravity (9.81 m/s 2 ).
BACKGROUND OF THE INVENTION
Processes for the production of quality paper pulps, capable of obtaining, with most plants, suitable breaking lengths, are by nature essentially chemical in which the cellulosic fibres of the lignocellulosic plant material are freed from plant cement which binds them in the plants, consisting of hemicelluloses (sugar polymers with 5 to 6 carbons) and lignins (polymers of substituted allylphenols) by a chemical hydrolysis action in a concentrated basic or acidic aqueous medium, often in the presence of sulphur in different oxidation states.
These processes are at the present time employed essentially in existing industrial units throughout the world.
They have a major disadvantage in that they require considerable quantities (approximately 20% by weight) of inorganic chemical products during the cooking of the plants to make paper pulp. These inorganic chemical products are necessarily, but with difficulty, recycled and they are often the origin of foul odours due to the presence of sulphur.
Moreover, these factories require enormous investments in order to meet basically acceptable environmental standards, and they are therefore only profitable for a high critical size of the order of 100 to 200,000 tonnes of pulp produced per year.
A technological improvement has been obtained by replacing all or part of the water by an organic solvent of the alcohol, ketone or ester type, which makes it possible to overcome the use of sulphur, but not basic reagents, and therefore problems of recycling these reagents remain. These so-called “organosolve” technologies which require high pressures and involve high operating costs, are not as yet developed industrially for these reasons.
With the same idea in mind, other technologies of the same type using organic acids for hydrolysing hemicelluloses and lignins and at the same time for freeing cellulose fibres have been developed on the pilot plant scale. These technologies make it possible to do away with inorganic reagents completely, which is a considerable advantage.
Formic acid (B. BUCHOLZ and R K. JORDAN Pulp and Paper, p. 102-104, 1983; M N. ERISMANN et al., Bioresource Technology, Vol. 47, p. 247-256, 1994) can be used and it makes it possible to make acceptable paper pulps without pressure.
This technology also makes it possible to preserve in the paper pulps the silica contained in the plant, which is an important advantage when annual plants are used as a raw material since silica considerably disrupts the recovery of inorganic reagents in current industrial processes in a basic medium.
A variant of the process such as one under the name MILOX proceeds by cooking with formic acid in several stages in the presence of hydrogen peroxide, which improves delignification (K. POPPIUS-LEVLIN et al., Tappi Journal, Vol. 80, No. 9, p. 215-221, 1997).
Acetic acid can be used with the same aim but under pressure at a higher temperature (160 to 180° C.) at concentrations in water of 50 to 90% (R. A. YOUNG and J. L. DAVIS, Holzforschung, Vol. 40, p. 99-108, 1986).
Delignification is correct but the process requires washing of the pulp with acetone in order to remove lignins precipitated on the pulp.
A variant of this process makes it possible, with oxygen under pressure, to reduce the cooking time and to improve delignification (C. P. NETO and A. ROBERT, Holzforschung, Vol. 46, p 233-240, 1993) but it is at the origin of partial depolymerisation of cellulose by the joint action of pH and oxygen.
A variant of the MILOX process using acetic acid and hydrogen peroxide in two stages at 160-170° C. has also been proposed (K. POPPIUS-LEVLIN et al., Paper and Timber, Vol. 73, p. 154-158, 1991) but it does not provide any considerable improvement.
The limited acidity of acetic acid has led to its hydrolysis capacity being reinforced by the addition of hydrochloric acid (J. C. PAJARO et al., Holz als Roh-und Werkstoff, Vol. 54, p. 119-125, 1996) at 115-130° C. The reduction in the reaction temperature is the principal improvement of the process which has a major advantage of introducing chlorine ions into the process (G. VASQUES et al., Holzforschung, Vol. 49, No. 1, p. 69-73, 1995).
In addition, it should be pointed out that all the technologies using, in two or more stages, an organic acid and hydrogen peroxide generating peroxyacids in situ, are detailed in the review (N. LIEBERGOTT Pulp and Paper Canada, Vol. 97, No. 2, p. 45-48, 1996).
It should be added that technologies for bleaching these pulps without chlorine use hydrogen peroxide in a basic medium, which involves the regulation of silica in the form of sodium silicate causing considerable problems during the draining of pulps and the recycling of reagents.
The object of the present invention is to provide a novel process for producing paper pulp at atmospheric pressure from annual or perennial plants which leads to good-quality chemical pulps preserving the endogenous silica in their structure.
Document EP-A-0 584 675 teaches a process for extracting cellulose from lignocelluloses, by heating for two hours at high temperatures (170° C. or 180° C.) and under pressure in the presence of aqueous acetic acid with the addition of formic acid.
Document WO-A-95/21960 describes a process for cooking lignocellulosic materials, in particular from annual plants, with a mixture of carboxylic acids, involving a compulsory pyrolysis step.
The object of the invention is a process which makes it possible to obtain these performances whatever the nature of the plants used and which is thus particularly valuable in the case of annual plants in order to open up the way to new economic developments, in particular in the case of cereal straw and cane sugar bagasse or sugar sorghum bagasse.
SUMMARY OF THE INVENTION
To this end, the process for producing paper pulp, lignins, sugars and acetic acid according to the invention is characterised in that it combines the following steps:
(i) the annual or perennial plants, used partially or totally, which constitute the lignocellulosic starting raw material, are placed in contact with a mixture of formic acid containing at least 5% of acetic acid by weight, and the whole is brought to a reaction temperature higher than 50° C.;
(ii) the solid fraction constituting the paper pulp is then separated from the organic phase, especially containing in solution the starting formic acid and acetic acid, solubilized monomeric and polymeric sugars, lignins and acetic acid derived from the initial plant raw material.
The process according to the invention results from the following surprising observation: the addition of acetic acid to formic acid makes it possible to increase considerably the dissolving power of the liquid organic phase as defined as regards hemicelluloses and lignins without affecting the capacity of formic acid for the acid hydrolysis of these biopolymers. In this way, degradation of cellulosic fibres is prevented which appears with concentrated formic acid alone under normal conditions of use, and thus the paper-making quality of the paper pulp obtained is preserved.
Strong pulps are then obtained which separate easily from the reaction medium and which drain easily on account of the non-salting out of endogenous silica.
This property is particularly valuable since it is the principal factor limiting the use of chemical pulps from straw in particular in fast paper machines of which they slow the speed.
It should be emphasised that the acetic and formic acids are recycled. Losses in the process do not exceed 1% by weight per tonne of pulp produced, which is negligible.
The mechanisms by which formic acid and acetic acid act in synergy in the first moments of cooking remain difficult to explain.
Nevertheless, a hypothesis may be advanced that, under the operating conditions in accordance with the process of the invention, the low hydration of the medium associated with the water provided by the initial lignocellulosic materials promotes the dissociation of formic acid, which brings about controlled hydrolysis of the hemicelluloses/lignins complex.
Under these conditions, acetic acid, preferably in molecular form, solubilises lignins freed in this way more easily. This effect makes it possible to limit the reaction time and the possible formylations of free hydroxyl groups of cellulose which degrade the paper-making qualities of the pulp.
The progressive release of acetic acid derived from the acetyl groups of hemicelluloses reinforces this effect, but it does not make it possible to obtain the performances observed in the process on account of its quantity that is too small in relation to the initial formic acid.
The process according to the invention may be put into operation from plants or parts of plants of the following types:
cereal straw (wheat, barley, rye, oats, tritical, rice, etc.) annual plants (cotton, hemp, flax, reed, etc.) perennial plants (bamboos, broad-leafed wood, resinous wood, etc.) sugar cane bagasse, sugar sorghum bagasse.
The process makes possible particularly valuable economic utilisation of annual plants, in particular straw and bagasse, which are considered in the processes for producing traditional chemical pulps as products of the second category without great value.
Care is preferably taken to ensure that the moisture content of the initial lignocellulosic material is less than or equal to 25% by weight of water based on the dry matter.
The lignocellulosic raw material is preferably ground so as to reduce it into fragments or chips substantially of between 0.5 and 20 cm in length.
DETAILED DESCRIPTION OF THE INVENTION
According to a first embodiment, the plant material is pre-impregnated at a temperature at least 30° C. below the reaction temperature. The impregnation by immersion is performed for a period from between 10 to 30 minutes in the formic acid/acetic acid mixture used during the fractionation reaction. Impregnation and the fractionation reaction which follow are carried out at atmospheric pressure.
Fractionation is here understood to mean the reaction process usually know under the name of cooking which, under the conditions of the invention, leads, in addition to paper pulp, to easily separable products, which is not the case in most conventional processes.
According to another embodiment, the fractionation reaction is performed at a temperature below or equal to the reflux temperature of the mixture.
The liquid/solid mass ratio will preferably be between 4 and 11.
Separation of the paper pulp from the organic phase at the end of cooking is preferably performed by pressing.
Another preferred embodiment specifies that the pulp separated in this way is washed with a mixture of formic acid and acetic acid or with pure acetic acid. The pulp from which most of the lignin residues and sugars have been removed is then washed with hot water.
Another preferred embodiment proceeds with cooking in at least two stages in order to improve delignification and therefore the quality of the pulps.
The first stage is performed in the presence of the formic acid/acetic acid mixture. The second stage is performed after having separated the pulp produced in the first stage in the presence of anhydrous acetic acid. Pulp washings are carried out with acetic acid.
One preferred embodiment specifies the control of pH during washing in an organic acid medium so that the paper pulp is at an ideal pH for bleaching with ozone in 1 or 2 sequences, at a dryness of the pulp of the order of 40 to 60%.
Another preferred embodiment specifies the separation of formic acid and acetic acid by evaporation under vacuum, the separation of entrained water, the recycling of formic and acetic acids in the required proportions and the recovery of excess acetic acid and water.
Another embodiment specifies taking up the lignins/sugars mixture in water and filtering or centrifuging the suspension in order to separate the lignins precipitated from the acidic aqueous sugar-containing phase. The latter is concentrated by evaporation under vacuum in order to recover the sugars and to recycle the condensed water.
The process of the invention is illustrated in the following examples:
EXAMPLE NO. 1
38 g of rice straw with 88% dryness (33.5 g of dry matter) were put into contact at ambient temperature (20° C.) with a mixture containing 150 g of pure formic acid and 150 g of pure acetic acid in a 2-liter reactor fitted with a central mechanical stirrer, an open condenser and a thermometer. Mechanical stirring was maintained at ambient temperature for 15 minutes which corresponded to the impregnating time.
The suspension was brought to a temperature of 100° C. in 35 minutes by means of a thermostatically controlled heating bath. This temperature was kept steady for 60 minutes. The pulp was drained and separated by pressing and was then washed twice in the reactor with 150 ml of a formic acid/acetic acid mixture in the initial reaction proportions for a period of 10 minutes.
The acidic washing solutions were separated from the pulp by filtration and pressing and the pulp was then washed with hot water in order to recover the residual traces of acids. The pulp was then washed with cold water until neutral.
The mechanical properties of the pulp obtained were as follows:
GR (grammage): 72.35 g/m 2 ; NF standard: Q 03019
T (thickness): 0.12 mm; NF standard: Q 03053
BL (breaking length): 4262 m; NF standard: Q 03002
TI (tear index): 337 mN·m 2 /g; NF standard: Q 03011
BI (burst index): 1.66 kPa; NF standard: Q 03053
EXAMPLE NO. 2
38 g of rice straw with 90% dryness (34.2 g of dry matter) were put into contact at ambient temperature (20° C.) with a mixture containing 210 g of pure formic acid and 90 g of pure acetic acid in a 2-liter reactor fitted with a central mechanical stirrer, an open condenser and a thermometer. Mechanical stirring was maintained at ambient temperature for 15 minutes which corresponded to the impregnating time.
The suspension was brought to a temperature of 85° C. in 25 minutes by means of a thermostatically controlled heating bath. This temperature was kept steady for 60 minutes. The pulp was drained and separated by pressing and was then washed twice in the reactor with 150 ml of a formic acid/acetic acid mixture in the initial reaction proportions for a period of 10 minutes.
The acidic washing solutions were separated from the pulp by filtration and pressing and the pulp was then washed with hot water and then cold water.
The mechanical properties of the pulp obtained were as follows:
GR (grammage): 74.17 g/m 2 ; NF standard: Q 03019
T (thickness): 0.125 mm; NF standard: Q 03053
BL (breaking length): 4517 m; NF standard: Q 03002
TI (tear index): 329 mN·m 2 /g; NF standard: Q 03011
BI (burst index): 1.83 kPa; NF standard: Q 03053
The pulp obtained (30 g) was then placed in a closed static reactor enabling a mixture of air and 1% ozone to diffuse through a sinter on which the pulp at a pH of 3 to approximately 50% dryness rested.
Bleaching was performed in two 20-minute sequences of gas-solid contact. Water washing was carried out between each sequence.
The whiteness index, measured with the aid of the ELREPHO spectrophotometer 2000 according to NF standard Q 03039, passed from 28.1 photovolts for the raw pulp to 68.2 photovolts for the pulp bleached under these conditions.
The mixture of formic and acetic acids obtained by evaporating the solution of sugars and lignins contained water provided by the lignocellulosic raw materials.
This water was separated from the mixture of acids by azeotropic distillation with the aid of a third body which could have been: ethyl acetate, benzene, toluene, n-butylethylether, cyclohexane, etc.
The excess acetic acid coming from the acetyl groups of the lignocellulosic material could then be separated off simply by rectification.
Under these conditions, 100 g of rice straw corresponding substantially to three identical tests under the experimental conditions described above provided the reaction medium with approximately 10 g of water. The organic liquid phase contained substantially 880 g of acetic and formic acids and 9.5 g of water. It was treated with 109 g of ethyl acetate. The ethyl acetate-water azeotrope (B.Pt 70.4° C. at 760 mm Hg, with a water concentration of 8.2% by weight) was extracted at the head of the distillation column and condensed.
Ethyl acetate was separated from water in a decanter and was recycled to the head of the column. The dried acetic acid/formic acid mixture was extracted at the foot of the column and could then be distilled in a rectifying column so as to recover the excess acetic acid.
The formic and acetic acids were then recycled to the cooking process in suitable proportions.
After evaporating off the organic acids, the mixture of sugars and lignins was treated with water recovered during washing of the pulp.
The lignins precipitated and were separated off by filtration and then dried. 11.2 g of lignins were recovered in this way. The sugar-containing solution was then evaporated, enabling the mixture of sugars mainly containing sugars with five carbon atoms to be finally recovered. The quantity of sugars recovered was 19.1 g.
EXAMPLE NO. 3
38 g of sorghum bagasse with 88% dryness (33.5 g of dry matter) were put into contact at ambient temperature (20° C.) with a mixture containing 220 g of pure formic acid and 90 g of pure acetic acid in a 2-liter reactor fitted with a central mechanical stirrer, an open condenser and a thermometer. Mechanical stirring was maintained at ambient temperature for 30 minutes which corresponded to the impregnating time.
The suspension was brought to a temperature of 100° C. in 30 minutes by means of a thermostatically controlled heating bath. This temperature was kept steady for 60 minutes. The pulp was drained and separated by pressing and was then washed twice in the reactor with 150 ml of a formic acid/acetic acid mixture in the initial reaction proportions for a period of 10 minutes.
The acidic washing solutions were separated from the pulp by filtration and pressing and the pulp was then washed with hot water in order to recover the residual traces of acids. The pulp was then washed with cold water until neutral.
The paper pulp obtained was characterized by its viscosimetric degree of polymerisation (DPv). The measurement was performed with the aid of a capillary viscometer of the “Commission de la Cellulose” type which serves to determine the intrinsic viscosity (in mPA·s) of natural or regenerated cellulose (NF T 12-005). The observed value is linked to the degree of polymerisation by the relationship DPv=(0.75 (954 log v−325))1.105 in which v is the measured viscosity, and therefore for the sugar sorghum bagasse pulp obtained under the experimental conditions described above, a DPv=1680, characteristic of a good-quality pulp.
EXAMPLE NO. 4
38 g of rice straw with 88% dryness (33.5 g of dry matter) were put into contact at ambient temperature (20° C.) with a mixture containing 220 g of pure formic acid and 90 g of pure acetic acid in a 2-liter reactor fitted with a central mechanical stirrer, an open condenser and a thermometer. Mechanical stirring was maintained at ambient temperature for 15 minutes which corresponded to the impregnating time.
The suspension was brought to a temperature of 100° C. in 30 minutes by means of a thermostatically controlled heating bath. This temperature was kept steady for 60 minutes. The pulp was drained and separated by pressing. The pulp was subjected to a second cooking with glacial acetic acid (150 ml) at a temperature of 90° C. for 30 minutes.
The new pulp obtained was drained, separated by pressing and washed three times with acetic acid (150 ml) for 15 minutes for each washing at a temperature of 95° C.
The acidic washing solutions were separated from the pulp by filtration and pressing and, and the pulp was then washed with hot water in order to recover the residual traces of acids. The pulp was then washed with cold water until neutral.
The degree of polymerisation of the sugar sorghum pulp measured under the conditions of example 3 had a particularly high value for DPv=2360 characteristic of a superior-quality paper pulp.
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A method for producing paper pulp from a lignocellulosie vegetable raw material. The method includes contacting the raw material with a mixture of formic acid and acetic acid (in an amount more than 5 wt. % of the mixture) at a temperature and for a suitable reaction time, the whole being performed at room temperature. The paper pulp is separated from the organic phase and optionally bleached with ozone. The organic phase is treated to enable the recycling of the formic and acetic acids and the extraction of lignins, sugars and excess acetic acid.
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BACKGROUND OF THE INVENTION
The process of designing integrated circuits typically involves a functional design step, followed by a physical design step. During the functional design step, a design concept is described using a hardware description language and is then converted into a netlist, which specifies the electronic components and the connections between the components. The physical design step specifies the placement of the electronic components or elements on the chip and routing of the connections between the electronic components, thereby implementing the netlist. The physical design process generates the physical design data, which are synonymously called layout data, layout, or target layout.
The layout data defines a set of binary patterns or objects, which are also called “geometric features” or “features”. Usually the objects are represented as a polygon or collection of polygons in the layout data in order to facilitate the specification of the objects.
Each object can be a part of an electronic component such as a gate of a transistor or a connection between components. Each polygon object has vertices and edges joining those vertices. Each vertex is usually defined by its coordinates in a Cartesian x-y coordinate system. In a typical very-large scale integrated (VLSI) circuit, most edges are parallel to the x or y axis, in a so-called Manhattan layout style.
Often the physical layout data are stored and transmitted in a machine-readable format such as GDSII format, OASIS™ format, or in a database such as OpenAccess database or Milkyway™ design database. See, for example, OpenAccess: The Standard API for Rapid EDA Tool Integration, © 2004 by Si2, Inc.; Milkyway Foundation Database for Nanometer Design, © 2003 by Synopsys, Inc.
In these formats or databases, the layouts are often described hierarchically. This has the advantage of reducing file sizes and improving efficiency for certain analysis or modification operations, since some repetitive patterns can be given certain unique names and then placed multiple times in the layout by simply referring to those names. Repeatedly describing or performing computations for the same structure in detail can thus be avoided.
In a hierarchical layout description, a cell is a collection of layout features that can be referenced as a whole object. Thus, cells can be included in the layout by reference. Inclusions by reference can further be nested.
Figuratively, the hierarchy of the layout resembles a tree. The leaves of a tree are attached to its branches. Branches are attached to larger branches. The hierarchy of branches continues until the trunk of the tree reaches its root. “Leaf cells” of a layout are cells that do not include any other cells by reference. A leaf cell comprises a set of primitive objects or features, which are usually polygons. A “child cell” is included in its “parent cell.” A “root cell” is not included in any other. A layout can have multiple root cells, resembling a forest with multiple trees. And cells can be referenced any number of times within a single parent cell or by multiple parent cells.
Cell references can take one of two forms: a Structure Reference (SREF) or an Array Reference (AREF). A structure reference places an instance (a copy) of a cell at a particular (x,y)-offset within a parent cell. Each instance has some transformation information, which can often include translation, magnification, reflection, and/or rotation. An array reference describes multiple instances of a cell that are placed on a set of locations that form a regular grid or array. The array is defined by: 1) a number of rows; 2) a number of columns, 3) row and column spacings, 4) (x, y) offset of an instance; and 5) a set of magnification, reflection, and rotation that are common to all cells in the array.
If a layout does not have hierarchy, it is called flat. A layout can be flat as per design. Sometimes a hierarchical layout can be flattened. “Flattening a layout” means removing its hierarchical organization by replacing each cell reference by the set of geometric features contained in the cell that is referenced.
Semiconductor device manufacturing comprises many steps of patterning layers of silicon wafers according to the layout data. A layer is either the substrate of the semiconductor wafer or a film deposited on the wafer. At some steps, a pattern is etched into a layer. At some other steps, ions are implanted, usually in a pattern, into the layer. Generally, patterning comprises: lithographic exposure, resist development, and resist etching.
The prevalent form of lithography is optical projection lithography. This involves first making a mask or reticle that embodies the pattern to be projected onto the wafer. An image of the mask's pattern is then optically projected onto a photoresist film coated on the wafer. This selectively exposes the photoresist. The latent image is then developed, thereby making a stencil on the wafer.
Presently, the most common optical lithography projectors are stepper-scanners. These instruments expose a slit shaped region, which is often 26 millimeters (mm)×8 mm on the wafer. The wafer is scanned under the slit by a motorized stage under interferometer control. The mask is scanned in synchronization with the wafer but at a higher speed to account for the reduction of the projector (typically 4×). One scan typically exposes a 26 mm×33 mm image field. Step-and-repeat lithography projectors expose the wafer a field at a time. A common field size here is 22 mm×22 mm. In either case, many exposure fields are needed to cover the wafer.
Other forms of lithography include mask-less optical projection lithography, where the mask is replaced by a spatial light modulator. The spatial modulator is typically an array of micro-machined mirrors that are illuminated and imaged onto the wafer. The spatial light modulator is driven by the lithography data. Direct electron-beam writing lithography, electron projection lithography, and imprint lithography are other forms of lithography.
Modern semiconductor lithography processes often print features that are smaller than the exposure wavelength. In this regime, called the low-k 1 regime, the field and wave nature of light is prevalent, and the finite aperture of the projection lens acts as a low-pass filter of spatial frequencies in the image. Thus, it may be difficult for the projection lens to reproduce the high spatial frequency components required to reproduce the sharp edges or corners in polygon objects, for example. Also, light entering a mask opening from one object may impact another shape in close proximity, leading to a complex interaction of the electric fields of adjacent objects. Thus, the final shapes that are produced on the wafer will often have rounded corners and may bulge towards adjacent objects in ways that can impact the process yield. This resulting image distortion, called optical proximity effect, is responsible for the most significant distortion that arises in the transfer of the mask pattern onto the wafer.
Optical Proximity Correction (OPC) is the process of changing, or pre-distorting, the target layout data to produce the lithography or mask data so that the pattern that is etched in the wafer is a closer replica of the target layout. The goal of OPC is to counter the distortions caused by the physical patterning process (see A. K-T Wong, Resolution enhancement techniques in optical lithography, SPIE Press, Vol. TT47, Bellingham, Wash., 2001; H. J. Levinson, Principles of Lithography, SPIE Press, Bellingham, Wash., 2001). In effect, the objects or polygons of the lithography data are modifications from those specified by the target layout in an effort to improve the reproduction fidelity of the critical geometric features. This is often accomplished by moving object edges and by adding additional objects to the layout to counter optical and process distortions. These corrections are required to ensure the intended target design pattern fidelity is met, improving the process window and consequently manufacturing yield.
Application of many resolution enhancement technologies (RET) can also have the effect of changing the layout data relative to the lithography data. RET also addresses distortion in the lithography process by pre-compensation. Typically, RET involves implementing a resolution enhancement technique such as the insertion of sub-resolution assist features (SRAF), phase shift enhancement using an attenuated phase mask, or designing a mask that includes quartz etching to introduce phase shifting across features.
Still further, functional requirements can lead to changes when migrating from the layout data to the lithography data. For example, electronic elements, including conductive traces and transistors, that lie on critical paths may be more aggressively modified to improve yields, possibly at the expense of other, lower priority paths.
In short, the target layout describes the pattern that the designer desires to render on the wafer to form the integrated circuit. It is usually different than the pattern that is actually rendered on the integrated circuit, and is therefore usually very different than the pattern submitted to the mask making process due to implementations of RET and OPC. Thus, the target layout, the lithography or mask data, and the pattern resulting on the wafer are typically distinct patterns.
Different techniques are used to simulate the transformation between the mask pattern and the pattern that is formed in the photo resist. The process for generating the OPC, RET, and other compensations for a given object or mask is typically an iterative process involving moving parts of or adding to the objects, and determining if the new objects result in a better resist pattern. In model-based OPC or RET, various process effects are simulated. Model-based OPC, for example, is a numerically intensive calculation that transforms the target layout into mask data.
SUMMARY OF THE INVENTION
One of the primary objectives of hierarchy management is to maximize reuse, in both representation and computation. A hierarchical representation encapsulates the detailed internal composition of a sub-circuit using the notion of a cell definition (a CellDef). The cell definition is then used or referred to in other cell definitions, possibly many times. Without having to repeat the detailed composition of the cell, a reference to the CellDef requires a minimal amount of information. Very significant savings in representational data volume can thus be accomplished.
A given CellDef can also serve as a natural unit for operational reuse. If the computation required for the analysis or manipulation (e.g. parasitic extraction, positional perturbations, RET, design rule checking (DRC), or OPC) based on a CellDef or one cell instance can be applied, with no or minimal additional effort, to all or a significant subset of other instances of the CellDef, very substantial reductions in computational effort may be realized. Furthermore, a hierarchical representation also allows for the partitioning of the overall analysis/manipulation task into a collection of subtasks, e.g one per CellDef. Multiple jobs may then be distributed across a large number of computational nodes on a network for concurrent execution. While this may not reduce the aggregate computational time, a major reduction in the overall turnaround time (TAT) is in itself extremely beneficial.
Evolving applications lead to new requirements on hierarchy management. For example, while conventional OPC techniques address some of the higher order distortions that occur between the layout pattern and the pattern formed in the photo-resist due to proximity effects, they fail to take into account distortions caused by other factors, such as position of the features in the reticle field or structural functionality requirements of the electrical components. A need exists to take into account such other factors, as well as the proximity effects, when managing a layout hierarchy. Collectively we call these applications layout optimization applications.
Moreover, a need exists to manage layout hierarchies on a scale larger than the extent of a single chip, for example, in order to take into account positional distortion effects across the entire reticle field.
Still further, a need exists to efficiently manage a hierarchy by making appropriate trade-offs between hierarchy management speed against compactness of the hierarchical representation.
One aspect of the present invention is directed to techniques for facilitating the preservation of the hierarchical organization that is common to layout data in the transition to the lithography data, which comprehends the required analysis or manipulation.
Another aspect of the invention is directed to extending the hierarchical organization across the entire reticle field. This allows for the specification of templates that extend over the entire field. Moreover, compensation for positional perturbations having field level extent can now be included, organically, in the lithography data.
In yet another aspect, the invention is directed to the distribution of the computational task for an integrated circuit layout design on a reticle field wide basis among a collection of networked computation nodes. This enables better concurrent execution, lowering turn around time.
In general, according to one aspect, the invention features a method for reticle field-wide hierarchy management. This method comprises providing placement information for a hierarchical chip layout across a reticle field and generating templates across that reticle field in accordance with the placement information.
In this way, the templates need no longer be limited to the level of the chip. Instead, the same templates can now be extended to span the entire reticle field.
One advantage is that corrections for positional effects or perturbations such as generated by the imperfections in the optics of the lithography system, which extend across the reticle, can now be included within the hierarchy of the lithography data.
In some examples, the step of providing placement information comprises providing locations for instances of the chip layout as array references across the reticle field. In other examples, coordinates are provided for the instances of the chip layout to thereby enable arbitrary placement of the instances in the reticle field.
In the typical example, a reticle field-level cell is defined that encompasses at least one chip level cell corresponding to the chip layout. This reticle field-level cell is often the root cell.
In a preferred embodiment, the step of generating the templates in accordance with the placement information comprises generating templates by grouping instances according to distinct environments. The environments are distinguished by proximity unit cells in regions adjacent to each of the instances. In other examples, the instances are distinguished by functional requirements or positional effects pertaining to each of the instances. These positional effects include lens aberration, optical flares and/or pupil illumination non-uniformity.
In another preferred embodiment, the step of generating the templates in accordance with the placement information comprises first grouping instances subject to common proximity perturbation effects and then further grouping the instances to address positional perturbation effects.
In general, according to another aspect, the invention also features a method of reticle field-wide hierarchy management in an integrated circuit chip layout design. This method comprises first receiving a chip layout in a hierarchical form. Then placement information for the chip layout is provided, locating the chip in the reticle field. Finally, templates are generated to thereby build a litho hierarchy tree for the entire reticle field in accordance with the placement information.
In a preferred embodiment, the step of generating the templates and building the litho hierarchy tree comprises, for each instance of a template candidate cell definition, determining an exterior environment. Then, amongst the exterior environments of the instances, a set of distinct environments is identified. The collection of instances is partitioned to create one or more templates in accordance with their respective environments.
In general, according to another aspect, the invention features a method of partitioning a plurality of instances of a template candidate cell in a hierarchical chip layout design. This method comprises identifying adjacent regions of each of the instances of the template candidate cell. Proximity environment definitions are generated for each of the instances of the template candidate cell. The proximity environment definitions comprise one or more proximity unit cells that overlap or are in contact with the adjacent regions of each of the instances. From this, a set of distinct environments is determined from the proximity environment definitions. Then instances of the template candidate are assigned to corresponding ones of the distinct environments based on the proximity unit cells information.
In a preferred embodiment, a pre-processing step creates clusters of primitive geometries into primitive unit cells, and provides each such cell with a unique numerical identifier. In the operation of trying to determine the identity of proximity environments, computational time is reduced by using these numerical identifiers, rather than by comparing elements of the primitive geometries in the adjacent regions of each instance.
Templates are defined for each CellDef containing subsets of the instances of the cell based on unique exterior environments. These templates can then be used as the units of distributed processing among a collection of networked computation nodes. The computation nodes perform the intended computations for the templates, preferably concurrently. In layout optimization applications, these computations include determining optical proximity corrections, corrections to address positional effects or perturbations, and/or possibly corrections to address functional requirements for those instances.
In general, according to another aspect, the invention features a method for distributing a computational task for an integrated circuit layout design on a reticle field-wide basis among a collection of networked computational nodes. The method comprises generating a plurality of templates and building a litho hierarchy tree across the entire reticle field in accordance with the placement information for the chip layout across the reticle field. Then, the computation tasks are assigned to the networked computational nodes for concurrent execution. Finally, the outputs of the computational nodes are assembled.
Typically, the process of assembling the outputs comprises creating a final processed circuit layout for the entire reticle field.
In general, according to another aspect, the invention features a computer software product for reticle field-wide hierarchy management. This product comprises a computer readable medium in which program instructions are stored. These instructions, when read by a computer, cause the computer to receive placement information for a hierarchical chip layout across a reticle field. Additionally, the instructions cause the computer to generate templates across the reticle field in accordance with the placement information.
In general, according to another aspect, the invention features a computer software product for reticle field-wide hierarchy management in an integrated circuit chip layout design. This product comprises a computer readable medium in which program instructions are stored. These instructions, when read by a computer, cause the computer to receive a chip layout in a hierarchical form, in addition to receiving placement information for the chip layout across the reticle field. The computer generates templates and then builds a litho hierarchy tree across the entire reticle field in accordance with the placement information.
In general, according to still another aspect, the invention features a computer software product for partitioning a plurality of instances of a template candidate cell in a hierarchical chip layout design. The product comprises a computer readable medium in which program instructions are stored. These instructions, when read by the computer, cause the computer to identify adjacent regions for each of the instances of the template candidate cell and generate proximity environment definitions for each of the instances of the template candidate. The proximity environment definitions comprise one or more primitive unit cells overlapping or in contact with adjacent regions of each of the instances. A set of unique environments is determined from the proximity environment definitions and the instances of the template candidate cell are assigned to a corresponding one of the unique environments based on the primitive unit cells.
In general, according to another aspect, the invention features a computer software product for distributing a computational task for an integrated circuit layout design on a reticle field-wide basis among a collection of networked computational nodes. The product comprises a computer readable medium in which program instructions are stored. These instructions, when read by a computer, cause the computer to generate a plurality of templates and build a litho hierarchy tree across the reticle field in accordance with placement information for the chip layout across the reticle field. The computational tasks for the templates are assigned to the networked computational nodes for concurrent execution. The outputs of the computational nodes are then assembled.
In general, according to another aspect, the invention features a mask fabricated using lithography data created using the reticle field-wide hierarchy management. Placement information for a hierarchical chip layout is provided across a reticle field and templates were generated across the reticle field in accordance with the placement information.
According to still other aspects, the invention features an integrated circuit manufactured according to the previous specified methods, or software products. Further, the invention also features integrated circuits manufactured with the layout data specified above.
The various aspects of the invention can be used separately or in combination.
The above and other features of the invention, including various novel details of construction and combinations of parts, and other advantages, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method and device embodying the invention are shown by way of illustration and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale; emphasis has instead been placed upon illustrating the principles of the invention. Of the drawings:
FIG. 1 is a schematic diagram showing the contents of the cell definition data structures according to an aspect of the present invention;
FIG. 2 shows further details of the cell definition data structure in a textual form;
FIG. 3 is a schematic diagram showing the cell instance Hierarchy Tree for a chip, as yet unmodified from a GDS input;
FIGS. 4 and 5 illustrate reticle fields, with chip images placed in the fields and further cell instances placed within those chip images;
FIGS. 6A and 6B illustrate the reticle field level Hierarchy Tree view for two reticle layouts;
FIG. 7 is a schematic diagram of the cell definition data structure, including an instance of the cell definition according to an aspect of the present invention;
FIG. 8 is a schematic diagram illustrating a cell definition, including the proximity environments and the associated cell instances, and also showing the formation of a template, a template instance or LithoCell;
FIG. 9 illustrates a top level chip layout containing five sub-cells and some inline geometries;
FIG. 10 illustrates further sub-cells in the exemplary cells A and C;
FIG. 11 shows the spatial arrangements of cell instances to illustrate the neighborhood relationship between such cell instances;
FIG. 12 is a schematic diagram illustrating a partial hierarchical tree view for the example layout shown in FIGS. 9-11 ;
FIG. 13 is a flow diagram illustrating the pre-processing performed on the layout data in preparation for template generation according to an aspect of the present invention;
FIG. 14A illustrates the CellDef structure with the addition of the primitive unit cell (PUC) information.
FIG. 14B illustrates the revised cell definition in which the proximity environments are defined using the PUC information;
FIG. 15 is a schematic diagram illustrating a Litho Hierarchy Tree according to an aspect of the present invention;
FIG. 16 illustrates the cell definition data structure after the creation of new cell definitions as a result of template generation.
FIG. 17 illustrates the cell definition data structure and associated templates, including the modified geometries after some layout manipulation application;
FIG. 18 illustrates the exterior and interior proximity environments for a cell instance and some sub-cells;
FIGS. 19A-D show the division of a reticle field into model zones and grids to account for positional effects;
FIG. 20A illustrates the distribution of the templates to computational nodes for concurrent execution according to an aspect of the present invention; and
FIG. 20B is a flow diagram illustrating the operation of the inventive distributed application.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hierarchical Representation
A hierarchical representation of a chip layout design comprises primarily a collection of data objects or structures: a set of cell definitions (CellDef's).
FIG. 1 shows how the cell definitions may look in such a layout design.
Specifically, the cell definitions are data objects or data structures that describe recurring patterns within the layout design. Each cell definition CellDef 1 , CellDef 2 , . . . CellDef N 100 is typically characterized by a name for the cell 110 . Further within the cell definition is typically a pointer 112 to the geometry information 114 . This geometry information 114 may contain one or more (possibly a very large number of) geometric features (polygons, lines, holes, rectangles, paths, texts . . . , etc.). Such geometric features are called inline geometries of the CellDef. Within the CellDef, sub-cell pointers 116 are also commonly provided. These are pointers to nested sub-cells 118 that may contain further inline geometries, and/or pointers to even further sub-cells. CellDef's thus reference each other in a “nested/hierarchical” fashion, without creating a circular loop.
FIG. 2 illustrates the content of an exemplary cell definition data object 100 as encoded in a textual form.
Specifically, the cell definition contains a cell definition name “CellDef” 110 . It further comprises the primitive polygon or shape information 114 . The cell definition may further comprise structure references 118 -S that are references to other sub-cells that are children cells to the present cell definition 100 . Further, array references 118 -A are provided to other cell definitions.
The full picture of a chip layout is embedded in a collection of cell instances S 1 . . . S 2 . . . Sn, as shown in FIG. 3 . A cell instance (CellInst) is the incarnation, called an instantiation, of a CellDef. The process starts from the instantiation of the root-cell ROOT to create the Root Cell Instance (RootInst). Preferably this corresponds to the definition of the top-level view of the chip, or, as will be described below in the case of a reticle-wide hierarchy, it can correspond to the definition of the top-level view of the reticle (i.e., collection of chip images). Following the specification of the root-cell, a new cell instance is next created for each of the cell references occurring in the root-cell cell definition.
The instantiation process is recursively applied to the cell instances, until a cell instance is reached that contains only primitive geometric features P and no further cell references in its definition.
Such cell instances are commonly shown pictorially in the form of a tree, called a Hierarchy Tree, an example of which is illustrated in FIG. 3 .
It is also possible for a layout design to contain multiple Root Cells. In that case, the multiple roots are just like trees in a forest. In such a situation, it is useful to create an overall chip-level root cell ChipRoot in which each of the multiple Root Cells is instantiated once.
Reticle Layout and Reticle Field-Wide Hierarchy
Referring to FIG. 4 , a reticle 350 that is used in manufacturing an integrated circuit is shown. Such reticles typically contain multiple copies of a chip image. In this case, the chip image 352 is replicated (similar to an AREF of a CellDef within a chip layout) 9 times, in a regular 3×3 array.
However, the placement of the chip image 352 does not have to be regular in nature. The chip image may be placed at arbitrary locations across a reticle field, similar to an SREF of a CellDef across a chip layout.
Further even, a reticle may contain images of different chips. Such an example is illustrated in FIG. 5 . Here the reticle contains 4 copies of a chip A, 4 copies of a chip B, 2 copies of a chip C, and 4 copies of another chip D. The chips are of varying sizes, and some of the placement configurations are not regular.
From a representational perspective, creating a field wide layout involves primarily adding a field-level root cell definition FieldRoot. In this FieldRoot there is one reference to a chip-level root cell ChipRoot for each placement of the corresponding chip image. The full extent of a field wide layout may also be looked at from a hierarchy tree perspective. If the reticle field contains images of different chip types, the resulting tree would look like that shown in FIG. 6A . In this case the sub-trees immediately below the FieldRoot are of different varieties. If the reticle contains images of just one chip type, these first level sub-trees would all be of the same kind, as illustrated in FIG. 6B .
Layout Templates
Given a hierarchical representation of a chip layout design and a reticle field layout in which one or more copies of the chip image is placed, various kinds of analysis and manipulation may be conducted using the representation to predict the behavior of the layout under various process conditions. An example is the lithographical patterning simulation, which takes a collection of layout features (polygons) and attempts to predict how the features may be imaged on the silicon surface, given certain process parameter values. Another example is the Optical Proximity/Process Corrections (OPC) application, which attempts to manipulate (modify) the layout features so that, when imaged on the silicon wafer, they more closely resemble the desired geometrical patterns.
In these applications, the behavior of or the modifications required for a specific geometric feature are not only a function of the feature itself, but are also highly dependent on those other features that happen to be situated in its surrounding or adjacent neighborhood. This neighborhood may theoretically extend indefinitely, but in practice there is a finite distance beyond which such influence is so small that its effect can reasonably be ignored in the analysis. Such influence is called the “proximity” effect and the finite distance is called the Range of Influence (ROI).
Generally, the ROI is a function of the parameters of the exposure system such as k (the wavelength) and NA (the numerical aperture). It also depends on such other factors as the degree of precision desired and the acceptable computational efforts. In one preferred embodiment, for a 193 nm stepper with an NA value of 0.75, the ROI is taken to be 0.6 micrometers (μm).
Thus, given an instance of a cell containing a collection of geometric features, in order to predict the behavior of these features, we need to know what other features are within a ring (or border) that is one ROI beyond the cell instance's boundary. These other features lying within the ROI ring are said to form the proximity “environment” or “neighborhood” of a particular cell instance. More precisely, the environment of a cell instance includes not only those geometric features from other cell instances that fall within the ROI ring of the subject instance, but also features from other cell instances overlapping with the extent of the subject instance. A cell instance's proximity environment is thus a function of where and how the instance is placed within its instantiating parent, and where and how that particular parent instance is placed, recursively all the way up to the root cell instance.
Given the proximity effects, the analysis or manipulation for different instances of a CellDef should not be conducted using just the information contained in the CellDef itself or one representative instance. Instead the proximity environment of each instance should also be taken into account in the operation. To facilitate that, the original CellDef and CellInst structures need to be expanded.
FIG. 7 illustrates an expanded cell definition that includes such proximity environment information, according to the principles of a preferred embodiment of the present invention.
Generally, for each CellDef, we need to look at all of its instances to see what and how many different proximity environments surround the instances. Each different proximity environment defines one environment extension (Env_n) 122 . The CellDef structure is expanded to include a pointer 120 to a list of environment extensions 122 . Each cell instance 108 , in addition to pointing to its defining CellDef 100 , also now needs to point to one of the environment extensions 122 that applies to the instance.
Thus, the set of instances of a CellDef is effectively further subgrouped based on the common proximity environments within the set. Those instances that share the same environment are grouped under one environment extension. Each unique environment extension 122 dictates one unique analysis or manipulation, and the results are applied to all instances sharing the same environment. While much emphasis will be given here to the environment being a function of proximity, in other embodiments of the invention, the environments will be further distinguished based upon position in the reticle field or functional considerations.
An instance 108 of a cell definition (CellDef) comprises a reference to the defining cell definition 100 . In addition, each cell instance data structure further comprises some location, orientation, transformation information, and an instance Id, as provided by LocOmt/Id 124 . It also provides a reference to the parent instance 126 and points to the next sibling instance 128 under the same parent, and a pointer 130 to the first of its own children.
Referring to FIG. 8 , the cell definition CellDef object 100 , including a unique proximity environment extension 122 , and all cell instances 108 having (or pointing to) the same environment extension 122 , is called a Template 150 . The cell definition CellDef 100 object, a unique environment extension 122 , and one cell instance 108 is referred to as a Template Instance or a LithoCell 151 .
The creation of these templates enables instances of a cell definition to be categorized by their proximity environments. Specifically, an instance is grouped with other instances having the same environment. Thus, the resulting templates can be used as a basis for various layout manipulation applications such as OPC modifications. Furthermore, the templates 150 can be used to form job units for distributed processing and may also serve as a unit for other optimizations.
Determining Proximity Environments of Cell Instances
FIG. 9 shows a simple layout to illustrate how instances of a CellDef may have different proximity environments and the complications involved in determining such environments.
Shown there is a top level view 152 of the layout that is comprised of a plurality of inline geometric features 154 and five sub-cell instances: two instances of a cell named Cell A (one of the instances is rotated 90° clockwise), two instances of a cell named Cell B (one of the instances is rotated), and one instance of a cell named Cell C.
FIG. 10 shows the detailed composition of two of the three first level cell instances. Thus Cell A is further comprised of sub-cells D, E, and F; cell C is comprised of sub-cells K and J. Going yet another level deeper, it shows that cell D is further comprised of sub-cells G and H, and cell K is comprised of sub-cells P, R, and Q.
FIG. 11 illustrates a zoomed-in view of this example layout by bringing out the detailed compositions of the two lower instances of Cell A and Cell C. As shown here, an instance of Cell H and an instance of Cell R are neighbors of each other.
Viewing the layout from a hierarchy tree perspective, FIG. 12 shows a partially expanded tree of the cell instance hierarchy. As can be seen, the two adjoining instances of Cell H and Cell R shown in FIG. 11 are situated in branches that are very far apart from each other in the tree structure. The key point to notice is, geometric features going into the proximity environment of a cell instance may come practically from other cell instances situated anywhere in the hierarchy tree.
Strictly speaking, the proximity environment of a cell instance is defined by the actual geometric features that fall within the ROI ring of its outer boundary. This essentially means that one way to compare proximity environments would be to fully “flatten” or expand the whole hierarchy, leading to very large data volume and long computations. However, according to a preferred embodiment of the invention, several optimizing preprocessing steps are performed, as illustrated in FIG. 13 , before templates are generated.
Not all cell definitions are suitable as a candidate for a template. For example, it is generally preferable for a template to be of a certain minimum size. A very small CellDef is likely to generate a very large collection of different proximity environments, which is undesirable. (One exception to this rule, however, is the Unit Cell in an Array Reference, such as the bit cell in a memory array.)
Thus, after receiving the layout design data in step 1010 , the next preprocessing step is to divide the set of CellDef's into two groups: those that are template candidates (TC) and those that are not template candidates (NTC) in step 1020 . The contents of an NTC cell will be flattened and processed as a part of whichever CellDef that references it. One simple criterion may be just by the cell size. Other more sophisticated criteria are also possible.
Among the TC cell definitions, cells that contain only primitive geometries (inline geometric features) or references to NTC CellDef's (i.e., no reference to other TC CellDef) are identified in step 1030 .
Then in step 1040 , all geometries in non template candidate cells are flattened and brought to the level of the TC CellDef's.
The raw geometric features are the objects in a layout manipulation operation. For each TC CellDef these features come from two sources: they are a part of the CellDef's inline geometries, or they are the result of flattening of any NTC cells referenced in the current CellDef.
These are the geometries, called Primary Geometries (PGeo's), which need to be operated on as far as the current template is concerned. All other geometries are contained in their respective templates and are to be handled within those templates, and because of the nested nature of the template structure, every polygon will be ultimately accounted for.
To facilitate the generation and the determination of the identity of proximity environments, we next cluster or tile the primary geometries (PGeo's) into some small units called primitive unit cells (PUC's) in step 1050 . In one preferred embodiment, each PUC is designed to be square and of a size roughly equal to the ROI. For the purpose of this disclosure, “roughly equal to” means between about 1.0 times and about 2.0 times the ROI, more preferably between about 1.0 times and 1.5 times the ROI, and most preferably about 1.2*ROI.
In a preferred embodiment, the PUC's contain primary geometry information, i.e., polygon descriptions. In other embodiments, the PUC's contain polygon information by reference, such as to other cells, in addition to possibly primary geometry information.
For each TC cell definition, a bounding box is generated in step 1060 . This bounding box will be used to approximate the proximity environments for instances of the CellDef.
Then, in step 1070 , for each PUC a unique identifier is assigned. This identifier, usually a numerical ID, is used to determine the identity of the environments of different instances of a CellDef. For each PUC a bounding square is also generated.
In an alternative embodiment, the PUC's are defined by dividing each TC CellDef into a regular grid. Grid cells that contain no geometric features can be safely ignored. Each PUC in the grid is preferably sized based on the ROI. In one preferred embodiment, each cell of the grid is a square having dimensions of 120% of the ROI, although as mentioned in connection with the embodiment using clusters of PGeo's, the grid dimensions can be as little as 100% or as much as 200% of the ROI. Each cell is then given a unique PUC identifier.
FIG. 14A illustrates the CellDef 100 structure with the addition of the PUC information.
Each CellDef 100 now contains a pointer 160 to a list of primitive unit cells (PUC's) 162 that together contain all the primary geometries (PGeo's) of the CellDef. Each PUC 162 contains information about its bounding square and is assigned a sortable unique ID.
As originally defined, the proximity environment of a cell instance is determined by the actual raw geometric features from other cell instances that overlap the ROI ring surrounding the given instance. With the creation of the PUC's 162 , we no longer have to deal with the actual geometries. Instead, each proximity environment is effectively defined by the list of PUC's (from other cell instances) that comprise the environment. The task of determining whether two cell instances of one CellDef have the same proximity environment now becomes the much easier (less computationally intensive) task of comparing two lists of PUC identities (plus the transformation information) to see if they are identical.
Generating the Templates
The main task remaining to complete the template generation is to traverse the cell instance tree to determine what different environments the instances of a CellDef are surrounded with and, for each cell instance, which environment extension 122 matches the particular instance's proximity environment. The cell instance structure as shown in FIG. 7 will now point to a specific environment extension 122 .
FIG. 14B illustrates the revised cell definition in which each proximity environment is defined using the PUC information. Each unique environment includes a pointer 164 to a sorted list 166 of PUC Id's, along with some transformation information pertaining to each PUC.
One tradeoff in using the PUC ID and the transformation information, instead of meticulously comparing each polygon in the ROI of each instance of a CellDef, is that we gain in identification speed, but may potentially lose slightly in terms of reuse. For example, we may disadvantageously conclude that two instances of a Cell Def have different proximity environments while in reality, if we were to actually examine/compare the primitive geometric features that fall within their respective ROI surroundings, the environments could be identical. The chance of such an occurrence is deemed small, however. And even if it were to happen, the results would still be correct.
As defined, for each cell definition CellDef the operation of generating or creating templates serves mainly to partition all of the instances of that CellDef into a number of disjoint sub-groups, each pertaining to a unique, distinct proximity environment. Each template serves as a standalone, independent sub-unit. Given that instances in the said sub-unit all have identical proximity environment, operations performed using one of them thus can be shared by all other instances in that unit, thereby achieving the savings in computational effort.
Furthermore, if for a given CellDef the process of template generation results in the identification of N distinct proximity environments among all of the instances of the said CellDef, and the creation of N templates (i.e., the cell instances are partitioned into N disjoint sub-groups), presumably these N sub-groups would also result in different outcomes in a subsequent layout manipulation processing such as an OPC application or other layout optimization application. To facilitate such subsequent processing, N new CellDef's will be created as a result of the template generation process. Thus instead of having instances of the given CellDef all pointing to the same original CellDef, each instance will now point to a new CellDef corresponding to the particular proximity environment that matches with the said instance, i.e., corresponding to the particular template of which the said instance is a part.
FIG. 15 illustrates a hierarchical tree view of a layout corresponding to the one shown in FIG. 3 after the template generation process. The tree is substantially the same as the one shown previously except for the fact that the various cell instances now point to some new cell definitions that were created in the process of template generation. In this example there are three instances of a CellDef called SI: two instances at level 1 and one instance at level 2 . Let us assume that as we go through the process of determining the unique proximity environments and generating the templates for the layout, we come to the conclusion that the two level 1 instances share the same proximity environment while the instance at level 2 has its own, distinct 2 nd environment. In that case, two templates will be created for CellDef SI, one encompassing the two level 1 instances and the other encompassing the single level 2 instance. In the process two new cell definitions will be created, designated S 1 a and S 1 b , with the cell instances pointing to their respective corresponding new cell definitions. This reformulated hierarchy tree is called the Litho Hierarchy Tree for the layout.
FIG. 16 illustrates the cell definition data structure after the creation of such new cell definitions. Specifically, for each original cell definition CellDef 100 , a number of new cellDefs 100 ′, designated CellDef/ 1 , CellDef/ 2 , CellDef/ 3 , . . . , are created, each corresponding to a template or one distinct proximity environment.
FIG. 17 illustrates the cell definition data structure and the associated templates, including the modified geometries after some layout manipulation application. Specifically, for each unique environment, a pointer 168 is added that refers to the modified geometries 170 that are generated from an application such as OPC or other layout optimizations. The computation only needs to be performed once for instances 108 within a given template, and the results will be shared by all instances of that template.
Exterior/Interior Proximity Environments
Templates as defined so far consider only proximity environments and are defined in a nested/recursive fashion. Any TC sub-cells referenced in a TC CellDef are defined as templates themselves and are to be processed as such. Thus when we talk about processing one template (one CellDef), we are actually processing only the inline polygons and those polygons in any NTC sub-cells that are “flattened” to the current CellDef level (i.e. the Primary Geometries—PGeo's).
FIG. 18 shows two additional groups of polygons that also need to be taken into account while processing the primary geometries of the current template. The first group contains the shapes in the outward proximity neighborhood that fall within the ROI region 330 of an instance 108 as discussed above. This is called the Exterior Proximity Environment 330 .
On the other hand, looking inwards, the polygons in a ring on the edge of each TC sub-cell 332 also have an effect on the processing of PGeo's of the current cell instance. This is called the Interior Proximity Environment 334 . By definition, a CellDef that results in multiple templates has multiple Exterior Proximity Environments. On the other hand, there is actually only one Interior Proximity Environment which is the same among all Templates resulting from a given CellDef. Polygons contained in both Exterior and Interior Proximity Environments are called Secondary Geometries.
Positional (Within Chip and Across Field) and Functional Effects
In OPC applications, how a polygon needs to be modified in order to print faithfully depends not only on the polygon itself, but also on other polygons in its surrounding region. This is the proximity effect as explained previously. Accordingly, OPC pre-distorts the layout features, taking into account polygons in the proximity of each geometric feature. Such proximity effect is invariant as the chip image is replicated multiple times across a reticle field. Thus, referring to the reticle layout example shown in FIG. 4 , the nine instances of the cell A across the reticle field all have the same proximity environment.
However, the behavior of a geometric feature depends not only on the feature itself and its neighboring shapes, but also on its exact position or location in the layout, both within the extent of one chip image as well as across different images when looked at from a reticle-wide perspective. This dependency on the feature's location in the imaging field is due to factors such as lens aberrations, optical flare, and illumination pupil non-uniformity. These factors have small but perceptible variations across the imaging field, and affect the polygon's printing behavior. These influences are called the Positional Effects.
Thus, given a collection of cell instances 108 of a CellDef having the same proximity environment, the computations and accordingly the end results may have to be different for different instances because of the positional effects. In the extreme, each instance may have to be treated individually; no sharing of computational efforts or output representations is feasible. On the other hand, for some applications (e.g., OPC), the positional effects represent only small perturbations over the proximity effects, such that treating the instances all separately may not be necessary.
FIGS. 19A-D illustrate how the positional effect is accounted for in one preferred embodiment of the present invention. Here the reticle field 152 (shown in FIG. 19A ) is divided into a (relatively) small number of zones 410 , as shown in FIG. 19B . Each zone 410 has an associated “model ID” and designates a region of the field within which the positional effects (aberrations, flares, . . . , etc) are presumed to be substantially identical. Notice that it is permissible for disjoint zones to have the same model ID. Furthermore, the reticle field is sub-divided into some small grids defined as rectangles or squares 412 , which are smaller than the zones. This is shown in FIG. 19C . Given two instances of a CellDef, these model ID's can be used to determine if they have the same “positional” environment, similar to how the PUC's are used to distinguish proximity environments. This allows us to partition instances of a CellDef according to their positional environments within the chip images 352 that are overlayed on model grid 412 and across the reticle field 152 , as shown in FIG. 19D .
In addition to the proximity and positional effects that would render the otherwise identical instances of a given CellDef different, necessitating different treatments of sub-groups of instances when performing various layout analysis or manipulation operations, sometimes operational or functional considerations may also make it necessary to treat certain instance or instances of the CellDef differently in order to better meet a certain performance target. For example, a given CellDef may have many instances throughout the chip. Some of those instances may form part of a critical signal net such that more sophisticated analysis algorithms or aggressively optimized OPC modifications are called for. Like the proximity effects, such functional effects similarly lead to further partitioning or sub-grouping of instances of the CellDef so that different sub-groups may be treated differently.
Another way of articulating concerns regarding functional considerations is in terms of feature tolerances. Often on critical paths, tolerances are tightened to improve yield, since greater control over feature variability is required to ensure proper operation. Thus, controlling feature tolerances and variation over the field can be addressed using techniques described in U.S. patent application Ser. No. 10/955,527, filed Sep. 30, 2004, assigned to the same assignee as the current invention, entitled Method and System for Managing Design Corrections for Optical and Process Effects Based on Feature Tolerances, by Vishnu Govind Kamat, which is incorporated herein by this reference in its entirety.
Extended Definition of an Exterior Environment and Reticle-Wide Templates
Given a CellDef and all of its instances within the chip and across the reticle field, the notion of a proximity environment allows us to partition the instances into sub-groups, each containing a subset of the instances having an identical proximity environment. Each such a sub-group leads to the definition of a template. Looking at the notion of an environment as a “differentiator” among the instances of the cell definition, an extended notion of an Exterior Environment can be defined that takes into account at least the following various types of effects: 1) the proximity effects; 2) the positional effects; 3) the functional/operational effects.
Depending on factors such as the accuracy desired, the amount of computation time to be spent, the size of the resulting data, one or more of these effect categories may be used to define the exterior environments, which are then used in turn to partition instances of a CellDef to form templates. All cell instances within one template can be considered to be identical in all respects, such that they may share the same representation and computation.
Templates thus generated have a scope extending across the entire reticle field. Referring to FIG. 4 , copies of the cell instance Inst_A 108 in different chip images 352 all have an identical proximity environment. They differ only as a result of positional and/or functional effects. Thus, the notion of templates is extended to cover the reticle-wide operation, with templates extending across the reticle field and between different chip images or chip instantiations. In effect, templates are defined, leading to a Litho Hierarchy Tree at the field level in accordance with the placement information for those chip images. The resulting templates thus take into account variations due to proximity, positional and/or functional effects resulting from the locations of all chip placements in the whole reticle field.
Using Interpolation
Instead of applying the positional environment to the full extent as a differentiator to partition instances of a CellDef into templates to account for positional effects, some of the instant inventors have proposed to determine the proximity and positional perturbation corrections for a set number of, usually a few, instances of a CellDef across a number of positions in a field. Then, requisite corrections are derived for other instances in the field by interpolating the results from the corrections calculated for those representative instances. This can be achieved by applying position dependent corrections to a few widely separated instances of a CellDef, and interpolating the corrections to other instances of the CellDef as a function of field position (x f , y f ). This is described in U.S. patent application Ser. No. 10/933,192 filed on Sep. 1, 2004, assigned to the same assignee as the current invention, entitled “Method for Correcting Position-Dependent Distortions in Patterning of Integrated Circuits,” which is incorporated herein in its entirety by this reference.
Computation Distribution and Reuse
Templates 150 provide a convenient way of dividing the task of analyzing or manipulating a hierarchically structured chip and the corresponding reticle-wide layout into sub-tasks for distributed processing. In one preferred embodiment the distribution is done on a per template basis.
FIG. 20A illustrates the distribution of the templates template 1 , template 2 , . . . template n ( 150 ) to different nodes 180 - 1 to 180 - 6 of a distributed computing system 182 .
The main objective here is to divide the overall layout manipulation task into a set of sub-tasks so that they can be distributed across a collection or cluster 182 of computational nodes 180 on a network 184 , thereby reducing the total turnaround time. The template structure provides a natural framework for job partition.
In the illustrated example, the nodes 180 form a cluster that is interconnected via a high speed backplane or bus 184 . A cluster controller or master 186 handles the distribution so that each node 180 receives a standalone, independent task. The programming instructions are stored in a computer readable medium such as a hard drive of the master 186 , or possibly a removable disk 188 , which is loaded into the master 186 and/or nodes 180 .
FIG. 20B is a flow diagram illustrating the process for the distributed computational task.
To affect distributed processing and load balancing among nodes 180 , a metric is first defined to quantify the amount of computations needed for each template 150 in step 210 . A simple way of doing this is by measuring the size/area of or by counting the number of polygons/vertices contained in the CellDef for the templates.
In step 212 , the jobs are dispatched and then monitored by the master 186 . Each node then runs the intended layout analyzer/manipulator 214 to create the modified geometry of the lithography data. The analyzer processes then return results in step 216 .
The distribution may be done either statically or dynamically by the master 186 . In the former, the jobs are statically allocated to a collection of computational nodes, based on the computational needs of the templates and the processor nodes available. In the latter case the allocation is done dynamically, controlled by a monitoring program which keeps track of the initiation and completion of the jobs and tries to balance the load among all the computational nodes.
While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
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A hierarchical representation encapsulates the detailed internal composition of a sub-circuit using the notion of a cell definition (a CellDef). The CellDef serves as a natural unit for operational reuse. If the computation required for the analysis or manipulation (e.g. parasitic extraction, RET, design rule confirmation (DRC), or OPC) based on a CellDef or one cell instance can be applied, with no or minimal additional effort, to all or a significant subset of other instances of the cell, very substantial reduction in computational effort may be realized. Furthermore, a hierarchical representation also allows for the partitioning of the overall analysis/manipulation task into a collection of subtasks, e.g. one per CellDef. Multiple jobs may then be distributed across a large number of computational nodes on a network for concurrent execution. While this may not reduce the aggregate computational time, a major reduction in the overall turnaround time (TAT) is in itself extremely beneficial.
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CROSS-REFERENCE TO RELATED APPLICATION
This application claims benefit of U.S. Provisional Patent Application No. 61/341,109, filed Mar. 26, 2010, which is incorporated by reference herein in its entirety.
TECHNICAL FIELD
The invention relates to the field of recombinant microbial biomass processing and enzyme purification. More specifically, a process is provided to improve the ability to partially-purify and/or concentrate a Thermotoga sp. acetyl xylan esterase having perhydrolytic activity using microfiltration.
BACKGROUND
Peroxycarboxylic acid compositions can be effective antimicrobial agents. Methods of using peroxycarboxylic acids to clean, disinfect, and/or sanitize hard surfaces, textiles, meat products, living plant tissues, and medical devices against undesirable microbial growth have been described (U.S. Pat. No. 6,545,047; U.S. Pat. No. 6,183,807; U.S. Pat. No. 6,518,307; U.S. Patent Application Publication No. 2003-0026846; and U.S. Pat. No. 5,683,724). Peroxycarboxylic acids have also been used in a various bleaching applications including, but not limited to, wood pulp bleaching/delignification and laundry care applications (European Patent 1040222B1; U.S. Pat. Nos. 5,552,018; 3,974,082; 5,296,161; and 5,364,554). The desired efficacious concentration of peroxycarboxylic acid may vary according to the product application (for example, ca. 500 ppm to 1000 ppm for medical instrument disinfection at neutral pH, ca. 30 ppm to 80 ppm for laundry bleaching or disinfection applications) in 1 min to 5 min reaction time at neutral to alkaline pH.
Enzymes structurally classified as members of family 7 of the carbohydrate esterases (CE-7) have been employed as perhydrolases to catalyze the reaction of hydrogen peroxide (or alternative peroxide reagent) with alkyl esters of carboxylic acids in water at a basic to acidic pH range (from ca. pH 10 to ca. pH 5) to produce an efficacious concentration of a peroxycarboxylic acid for such applications as disinfection (such as medical instruments, hard surfaces, textiles), bleaching (such as wood pulp or paper pulp processing/delignification, textile bleaching and laundry care applications), and other laundry care applications such as destaining, deodorizing, and sanitization (Published U.S. Patent Application Nos. 2008-0176783, 2008-0176299, 2009-0005590, and 2010-0041752 to DiCosimo et al.). The CE-7 enzymes have been found to have high specific activity for perhydrolysis of esters, particularly acetyl esters of alcohols, diols and glycerols. Published U.S. Patent Application No. 2010-0087529 to DiCosimo et al. describes several variant CE-7 perhydrolases derived from several Thermotoga sp. having higher perhydrolytic specific activity and/or improved selectivity for perhydrolysis when used to prepare peroxycarboxylic acid from carboxylic acid esters. One of the variants described in Published U.S. Patent Application No. 2010-0087529, Thermotoga maritima C277S, exhibited a significant improvement in specific activity relative to the T. maritima wild-type enzyme.
Recombinant microbial production of an enzyme often includes one or more downstream biomass processing steps used to partially or completely purify and/or concentrate the recombinant enzyme from other components of the biomass. However, considerable difficulty has been encountered when filtering or concentrating protein preparations on microfiltration membranes. The purpose of the filtration is to pass a solution containing the perhydrolase through the membranes while retaining particles greater than 0.2 microns or 0.45 microns in the retentate. The protein is often retained, at least in part, by the membrane, rather than passing through it, where the porosity of the membrane is such that the protein should freely pass through it.
One of the biomass components that may be adversely impacting the ability to recovery and/or concentrate the desired enzyme catalyst is the presence of DNA in the cell homogenate. However, the addition of an exogenous deoxyribonuclease (DNAse) may not be cost effective, especially for industrial scale fermentations, and the use of mammalian sources of DNAse may be undesirable in toll fermentation.
The problem to be solved is to provide a facile and cost-effective process to obtain a concentrate comprising a recombinant enzyme having perhydrolytic activity, preferably a process that does not include the use of an exogenous deoxyribonuclease.
SUMMARY
The problem has been solved by providing a two-stage heat treatment process suitable for treating microbial cell homogenate comprising at least one thermophilic enzyme having perhydrolytic activity. The insoluble components in the heat-treated microbial cell homogenate are removed and resulting solution containing the perhydrolytic enzyme is subsequently concentrated to produce a concentrate comprising the perhydrolytic enzyme.
In one embodiment, a process is provided comprising:
a) providing a microbial cell homogenate comprising soluble and insoluble components, wherein said microbial cell homogenate comprises a recombinantly-produced thermophilic enzyme having perhydrolytic activity;
b) subjecting the microbial cell homogenate to a first heat treatment ranging from at least 4 hours but no more than 24 hours at a temperature ranging from 40° C. to 65° C.;
c) subjecting the heat-treated microbial cell homogenate from step b) to a second heat treatment ranging from 5 minutes to 4 hours at a temperature ranging from 75° C. to 85° C.;
d) removing the insoluble components from the microbial cell homogenate obtained after performing step (b) and step (c) by centrifugation or filtration to obtain a solution comprising the recombinantly-produced thermophilic enzyme having perhydrolytic activity; and
e) concentrating the solution comprising the thermophilic enzyme of step (d) by filtration, evaporation or a combination of protein precipitation and redissolution whereby a concentrate is obtained comprising the recombinant thermophilic enzyme having perhydrolytic activity.
In another embodiment, the microbial cell homogenate of step (a) is an Escherichia coli cell homogenate.
In another embodiment, an exogenous nuclease is not present in steps (a) through (d).
In another embodiment, the removal of the solid components from the microbial cell homogenate obtained after performing step (b) and step (c) is performed in step (d) using filtration.
In another embodiment, the removal of the solid components from the microbial cell homogenate obtained after performing step (b) and step (c) is performed in step (d) using a membrane having size exclusion cutoffs ranging from 0.45 microns to 0.20 microns.
In another embodiment, the membrane used in step (d) retains insoluble particles with an average diameter greater than 0.2 microns.
In another embodiment, the removal of the insoluble components from the microbial cell homogenate obtained after performing step (b) and step (c) is performed in step (d) using centrifugation.
In another embodiment, the concentration of the solution produced in step (d) is performed in step (e) using filtration.
In another embodiment, the concentration of the solution produced in step (d) is performed in step (e) using a membrane having size exclusion cutoffs ranging from 100 kDa to 30 kDa.
In another embodiment, the concentration of the solution produced in step (d) is performed in step (e) using evaporation.
In another embodiment, the concentration of the solution produced in step (d) is performed in step (e) using a combination of protein precipitation and redissolution.
In another embodiment, the recombinantly-produced thermophilic enzyme comprises a CE-7 signature motif comprising:
an RGQ motif corresponding to amino acid positions 118-120 of SEQ ID NO: 8;
a GXSQG motif corresponding to amino acid positions 186-190 of SEQ ID NO: 8; and
an HE motif corresponding to amino acid positions 303-304 of SEQ ID NO: 8.
In another embodiment, the thermophilic enzyme having perhydrolytic activity is an acetyl xylan esterase derived from a Thermotoga sp. In another embodiment, the thermophilic enzyme comprises an amino acid sequence selected from the group consisting of SEQ ID NOs 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 30, 31, 32, 33, 34, 36, 37, 38, 39, 40, 42, 43, 44, 45, and 46.
BRIEF DESCRIPTION OF THE FIGURES
FIGS. 1A through 1D . Chromatograms of lysate supernatants after different processing steps: ( FIG. 1A ) crude lysate, ( FIG. 1B ) lysate after incubation at 50° C., ( FIG. 1C ) lysate after incubation at 50° C. and heat-treatment at 75° C., and ( FIG. 1D ) lysate after heat-treatment at 75° C. (no 50° C. incubation). All chromatograms have same vertical scale, from −100 to +4500 mAU. FIGS. 2A through 2C . Chromatograms of lysate supernatants after different processing steps: ( FIG. 2A ) homogenization and incubation at 50° C., ( FIG. 2B ) incubation at 50° C. and homogenization, and ( FIG. 2C ) incubation at 50° C. followed by homogenization and subsequent heat treatment at 75° C. All chromatograms have same vertical scale, from −100 to +4500 mAU.
FIG. 3 . 1 st stage temperature 45° C. for 8 h, 2 nd stage treatment 75° C. for 2 h.
FIG. 4 . 1 st stage temperature 50° C. for 8 h, 2 nd stage treatment 75° C. for 2 h.
FIG. 5 . 1 st stage temperature 55° C. for 8 h, 2 nd stage treatment 75° C. for 2 h.
FIG. 6 . No heat treatment of cell homogenate.
FIGS. 7 through 21 . The SEC chromatograms for the remaining conditions for heat treatment outlined in Table 5, all demonstrating reduction in DNA at fractions 42-mL to 46-mL, and resolved perhydrolase at fractions 82-mL to 86-m L.
FIG. 22 . SEC chromatogram (control) showing the effect of single stage heat treatment (75° C.).
FIG. 23 . SEC chromatogram (control) showing the effect of single stage heat treatment (85° C.).
BRIEF DESCRIPTION OF THE BIOLOGICAL SEQUENCES
The following sequences comply with 37 C.F.R. §§1.821-1.825 (“Requirements for Patent Applications Containing Nucleotide Sequences and/or Amino Acid Sequence Disclosures—the Sequence Rules”) and are consistent with World Intellectual Property Organization (WIPO) Standard ST. 25 (1998) and the sequence listing requirements of the European Patent Convention (EPC) and the Patent Cooperation Treaty (PCT) Rules 5.2 and 49.5 (a-bis), and Section 208 and Annex C of the Administrative Instructions. The symbols and format used for nucleotide and amino acid sequence data comply with the rules set forth in 37 C.F.R. §1.822.
TABLE 1
A non-comprehensive list of CE-7 carbohydrate esterases having
perhydrolytic activity and their associated sequence identification
numbers. The members in the list are derived from thermophilic
microorganisms (e.g., Thermotoga sp.).
Nucleic
Amino
acid 1
acid
sequence
sequence
(SEQ
(SEQ
Enzyme ID
ID NO:)
ID NO:)
Reference
Thermotoga neapolitana WT
1
2
US 2008-0176783
T. neapolitana C277A
—
3
US 2010-0087529
T. neapolitana C277V
—
4
US 2010-0087529
T. neapolitana C277S
—
5
US 2010-0087529
T. neapolitana C277T
—
6
US 2010-0087529
Thermotoga maritima WT
7
8
US 2008-0176783
T. maritima C277A
—
9
US 2010-0087529
T. maritima C277V
—
10
US 2010-0087529
T. maritima C277S
—
11
US 2010-0087529
T. maritima C277T
—
12
US 2010-0087529
T. maritima
—
13
US 12/632,438
F24I/S35T/Q179L/N275D/
C277S/S308G/F317S
T. maritima
—
14
US 12/632,438
N275D/C277S
T. maritima
—
15
US 12/632,438
C277S/F317S
T. maritima
—
16
US 12/632,438
S35T/C277S
T. maritima
—
17
US 12/632,438
Q179L/C277S
T. maritima
—
18
Co-pending US
L8R/L125Q/Q176L/V183D/
provisional
F247I/C277S/P292L
attorney docket
number
CL5035
T. maritima
—
19
Co-pending US
K77E/A266E/C277S
provisional
attorney docket
number
CL5035
T. maritima
—
20
Co-pending US
F27Y/I149V/A266V/C277S/
provisional
I295T/N302S
attorney docket
number
CL5035
T. maritima
—
21
Co-pending US
L195Q/C277S
provisional
attorney docket
number
CL5035
T. maritima
—
22
Co-pending US
Y110F/C277S
provisional
attorney docket
number
CL5035
Thermotoga lettingae WT
23
24
US 2009-0005590
T. lettingae C277A
—
25
US 2010-0087529
T. lettingae C277V
—
26
US 2010-0087529
T. lettingae C277S
—
27
US 2010-0087529
T. lettingae C277T
—
28
US 2010-0087529
Thermotoga petrophila WT
29
30
US 2009-0005590
T. petrophila C277A
—
31
US 2010-0087529
T. petrophila C277V
—
32
US 2010-0087529
T. petrophila C277S
—
33
US 2010-0087529
T. petrophila C277T
—
34
US 2010-0087529
Thermotoga sp. RQ2(a) WT
35
36
US 2009-0005590
Thermotoga sp. RQ2(a)
—
37
US 2010-0087529
C277A
Thermotoga sp. RQ2(a)
—
38
US 2010-0087529
C277V
Thermotoga sp. RQ2(a)
—
39
US 2010-0087529
C277S
Thermotoga sp. RQ2(a)
—
40
US 2010-0087529
C277T
Thermotoga sp. RQ2 (b) WT
41
42
US 2009-0005590
Thermotoga sp. RQ2 (b)
—
43
US 2010-0087529
C278A
Thermotoga sp. RQ2 (b)
—
44
US 2010-0087529
C278V
Thermotoga sp. RQ2 (b)
—
45
US 2010-0087529
C278S
Thermotoga sp. RQ2 (b)
—
46
US 2010-0087529
C278T
1 = codon optimized for recombinant expression in E. coli .
Polynucleotide sequences encoding wild type polypeptide sequences are provided. WT = wild-type CE-7 carbohydrate esterase.
SEQ ID NOs: 47, 48, 50, and 51 are the nucleic acid sequences primers used in Example 1.
SEQ ID NO: 49 is the nucleic acid sequence of the polynucleotide prepared using PCR primers SEQ ID NO: 47 and SEQ ID NO: 48.
SEQ ID NO: 52 is the nucleic acid sequence of the polynucleotide prepared using PCR primers SEQ ID NO: 50 and SEQ ID NO: 51.
SEQ ID NOs: 53-60 are the sequences of oligonucleotides used to prepare T. maritime variants C277V, C277A, C277S, and C277T.
DETAILED DESCRIPTION
The present process comprising two heat-treatment steps is used to aid in purifying and/or concentrating a thermophilic enzyme having perhydrolytic activity such that the ease of filterability of the enzyme through a membrane is enabled or enhanced.
In this disclosure, a number of terms and abbreviations are used. The following definitions apply unless specifically stated otherwise.
As used herein, the articles “a”, “an”, and “the” preceding an element or component of the invention are intended to be nonrestrictive regarding the number of instances (i.e., occurrences) of the element or component. Therefore “a”, “an” and “the” should be read to include one or at least one, and the singular word form of the element or component also includes the plural unless the number is obviously meant to be singular.
The term “comprising” means the presence of the stated features, integers, steps, or components as referred to in the claims, but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. The term “comprising” is intended to include embodiments encompassed by the terms “consisting essentially of” and “consisting of”. Similarly, the term “consisting essentially of” is intended to include embodiments encompassed by the term “consisting of”.
As used herein, the term “about” modifying the quantity of an ingredient or reactant employed refers to variation in the numerical quantity that can occur, for example, through typical measuring and liquid handling procedures used for making concentrates or use solutions in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of the ingredients employed to make the compositions or carry out the methods; and the like. The term “about” also encompasses amounts that differ due to different equilibrium conditions for a composition resulting from a particular initial mixture. Whether or not modified by the term “about”, the claims include equivalents to the quantities.
Where present, all ranges are inclusive and combinable. For example, when a range of “1 to 5” is recited, the recited range should be construed as including ranges “1 to 4”, “1 to 3”, “1-2”, “1-2 & 4-5”, “1-3 & 5”, and the like.
As used herein, the term “peroxycarboxylic acid” is synonymous with peracid, peroxyacid, peroxy acid, percarboxylic acid and peroxoic acid.
As used herein, the term “peracetic acid” is abbreviated as “PAA” and is synonymous with peroxyacetic acid, ethaneperoxoic acid and all other synonyms of CAS Registry Number 79-21-0.
As used herein, the terms “enzyme catalyst” and “perhydrolase catalyst” refer to a catalyst comprising an enzyme (i.e., a polypeptide) having perhydrolysis activity.
As used herein, the term “perhydrolysis” or “perhydrolytic reaction” is defined as the reaction of a selected substrate with a source of hydrogen peroxide to form a peroxycarboxylic acid. Typically, inorganic peroxide is reacted with the selected substrate in the presence of a catalyst having perhydrolytic activity to produce the peroxycarboxylic acid. As used herein, the term “chemical perhydrolysis” includes perhydrolysis reactions in which a substrate (such as a peroxycarboxylic acid precursor) is combined with a source of hydrogen peroxide wherein peroxycarboxylic acid is formed in the absence of an enzyme catalyst. As used herein, the term “enzymatic perhydrolysis” refers a reaction of a selected substrate with a source of hydrogen peroxide to form a peroxycarboxylic acid, wherein the reaction is catalyzed by an enzyme catalyst having perhydrolysis activity.
As used herein, the term “perhydrolase activity” refers to the enzyme catalyst activity per unit mass (for example, milligram) of protein, dry cell weight, or immobilized catalyst weight.
As used herein, “one unit of enzyme activity” or “one unit of activity” or “U” is defined as the amount of perhydrolytic activity required for the production of 1 μmol of peroxycarboxylic acid product (such as peracetic acid) per minute at a specified temperature. “One unit of enzyme activity” may also be used herein to refer to the amount of peroxycarboxylic acid hydrolysis activity required for the hydrolysis of 1 μmol of peroxycarboxylic acid (e.g., peracetic acid) per minute at a specified temperature.
As used herein, the term “exogenous nuclease” refers to the addition and/or presence of a non-endogenous enzyme that catalyzes the hydrolytic cleavage of phosphodiester linkages in the DNA backbone. Fermentation biomass processing often includes the exogenous addition of a commercially-available deoxyribonuclease, such as deoxyribonuclease I from bovine pancreas (DN25; Sigma Aldrich, St. Louis, Mo.), to the biomass to aid in the degradation of DNA. However, the addition of an exogenous nuclease may increases the cost of biomass process, and the use of mammalian sources of DNAse may be undesirable in toll fermentation. In one embodiment, an exogenous deoxyribonuclease is not used in the present process.
Preparation of Microbial Cell Homogenate
The present process comprises subjecting a microbial cell homogenate (comprising the recombinantly produced perhydrolytic enzyme) to two distinct heat treatment steps. As use herein, the term “microbial cell homogenate” comprises soluble and insoluble components obtained after lysing the host cell used to recombinantly produce the enzyme having perhydrolytic activity. Typically the homogenate comprises a substantially aqueous matrix where the relative concentration of the homogenate may be adjusted to a desired concentration prior to initiating the first heat treatment step. The microbial host cell may be lysed using any number of methods know in the art, such as chemical, enzymatic, mechanical lysis (e.g., French press or dairy homogenizer) or any combination thereof. The microbial cells and/or microbial cell homogenate may be pH adjusted and/or may include the addition of a buffer prior to the first heat treatment step. In a preferred aspect, the pH of the microbial cell homogenate may be adjusted to a pH of about 6.5 to about 7.5 prior to the first heat treatment. In a further aspect, a phosphate or bicarbonate buffer may be included. In a further embodiment, magnesium sulfate may also be present in the microbial cell homogenate, preferably at a concentration ranging from 0.1 to 10 mM, more preferably 2 mM.
Two-Stage Heat Treatment
The present process comprises two distinct heat treatment steps.
As used herein, the terms “heat treatment”, “heat treatment period”, “heat-treated”, and “heating” are used to describe the process steps of subjecting a microbial cell homogenate to a specified temperature or temperature range for a specified period of time. The present process comprises a first heat treatment and a second heat treatment.
As used herein, the term “first heat treatment”, “first heat-treatment period” or “incubation step” refers to a process step wherein the microbial cell homogenate comprising a recombinantly-produced thermophilic enzyme is subjected to a temperature range from about 40° C. to about 65° C. for a period of time ranging from 4 hours to 24 hours, preferably using a temperature range of about 45° C. to about 55° C. for about 4 hours to about 16 hours. Although not bound by theory, the conditions of the first heat-treatment step are selected such that the endogenous nucleases present in the homogenate are active for at least a portion or all of the first heat-treatment period. In one embodiment, an exogenous deoxyribonuclease (DNAse) is not present in the first and/or second heat treatment step.
As used herein, the term “second heat treatment” or “second heat-treatment period” refers to a process step wherein the resulting “heat-treated” microbial cell homogenate from the first heat treatment is subsequently subjected to a second heat treatment comprising a temperature range from about 75° C. to about 85° C. for a period of time ranging from about 5 minutes to about 24 hours, preferably using a temperature range of about 75° C. to about 85° C. for about 30 minutes to about 4 hours.
Removal of Insoluble Components after the Second Heat Treatment
The insoluble components in the heat-treated microbial cell homogenate may be separated from the soluble components using centrifugation or filtration. The resulting solution comprises the recombinantly produced thermophilic enzyme having perhydrolytic activity.
In one embodiment, the removal of the insoluble (solid) components from the microbial cell biomass obtained after the second heat treatment comprises filtration using a membrane having size exclusion cut-offs ranging from 0.45 microns to 0.20 microns. In a preferred aspect, the membrane retains particles greater than 0.2 microns in average diameter.
The perhydrolytic enzyme in the resulting solution is then concentrated by filtration, evaporation or a combination of protein precipitation and redissolution whereby a concentrate is obtained comprising the recombinant thermophilic enzyme having perhydrolytic activity.
In one embodiment, filtration is used to concentrate the solution after the insoluble components are removed. In another embodiment, the filtration step used to concentrate the solution uses a membrane having a size exclusion cut-off range from 100 kDa to 30 kDa.
In another embodiment, evaporation is used to concentrate the solution after the insoluble components are removed in step (d).
In another embodiment, a combination of protein precipitation and redissolution is used to produce a concentrate from the solution obtained from step (d).
In one embodiment, the weight percent (wt %) of the recombinant thermophilic enzyme having perhydrolytic activity in the concentrate is at least 2.5 wt %. In a preferred embodiment, the weight percent (wt %) of the recombinant thermophilic enzyme having perhydrolytic activity in the concentrate is at least 5.0 wt %.
Carbohydrate Esterases (Family 7) Having Perhydrolytic Activity
Members of the CE-7 family include cephalosporin C deacetylases (CAHs; E.C. 3.1.1.41) and acetyl xylan esterases (AXEs; E.C. 3.1.1.72). Members of the CE-7 esterase family share a conserved signature motif (Vincent et al., J. Mol. Biol., 330:593-606 (2003)). As used herein, the terms “signature motif” and “CE-7 signature motif”, refer to conserved structures shared among a family of enzymes having a perhydrolytic activity.
As used herein, “structurally classified as a CE-7 enzyme”, “structurally classified as a carbohydrate esterase family 7 enzyme”, “structurally classified as a CE-7 carbohydrate esterase”, and “CE-7 perhydrolase” will be used to refer to enzymes having perhydrolysis activity that are structurally classified as a CE-7 carbohydrate esterase based on the presence of the CE-7 signature motif (Vincent et al., supra). As used herein, the “signature motif” for CE-7 esterases comprises three conserved motifs (residue position numbering relative to reference sequence SEQ ID NO: 2; the wild-type Thermotoga maritime acetyl xylan esterase):
a) Arg118-Gly119-Gln120;
b) Gly186-Xaa187-Ser188-Gln189-Gly190; and
c) His303-Glu304.
Typically, the Xaa at amino acid residue position 187 is glycine, alanine, proline, tryptophan, or threonine. Two of the three amino acid residues belonging to the catalytic triad are in bold. In one embodiment, the Xaa at amino acid residue position 187 is selected from the group consisting of glycine, alanine, proline, tryptophan, and threonine.
Further analysis of the conserved motifs within the CE-7 carbohydrate esterase family indicates the presence of an additional conserved motif (LXD at amino acid positions 272-274 of SEQ ID NO: 2) that may be used to further define a member of the CE-7 carbohydrate esterase family. In a further embodiment, the signature motif defined above includes a fourth conserved motif defined as:
Leu272-Xaa273-Asp274.
The Xaa at amino acid residue position 273 is typically isoleucine, valine, or methionine. The fourth motif includes the aspartic acid residue (bold) belonging to the catalytic triad (Ser188-Asp274-His303).
Perhydrolases comprising the CE-7 signature motif and/or a substantially similar structure are suitable for use in the present process as long as they enzyme is not permanently or substantially inactivated (i.e., loss of perhydrolytic activity) by the second temperature treatment conditions of present process. Means to identify substantially similar biological molecules are well known in the art (e.g. sequence alignment protocols, nucleic acid hybridizations, presence of a conserved signature motif, etc.). In one aspect, the enzyme catalyst may comprise a substantially similar enzyme having at least 40%, preferably at least 50%, more preferably at least 60%, even more preferable at least 70%, even more preferably at least 80%, yet even more preferable at least 90% identity, and most preferably at least 95% amino acid identity to the sequences provided herein.
As used herein, the terms “cephalosporin C deacetylase” and “cephalosporin C acetyl hydrolase” refer to an enzyme (E.C. 3.1.1.41) that catalyzes the deacetylation of cephalosporins such as cephalosporin C and 7-aminocephalosporanic acid (Mitsushima, Kenji, et al., Appl. Environ. Microbiol . (1995) 61(6):2224-2229). As described herein, several cephalosporin C deacetylases are provided having significant perhydrolysis activity.
As used herein, “acetyl xylan esterase” refers to an enzyme (E.C. 3.1.1.72; AXEs) that catalyzes the deacetylation of acetylated xylans and other acetylated saccharides. As illustrated herein, several enzymes classified as acetyl xylan esterases are provided having significant perhydrolase activity.
Members of the CE-7 carbohydrate esterase family comprising a CE-7 signature motif having excellent perhydrolytic activity for producing peroxycarboxylic acids for carboxylic acid ester substrates and a source of peroxygen, such as hydrogen peroxide (Published U.S. Patent Application Publication No. 2008-0176783 to DiCosimo et al). A host of variant enzymes derived from naturally occurring acetyl xylan esterases obtained from thermophilic microorganisms, such as members of the genus Thermotoga , have also been produced. A non-limiting list of perhydrolytic enzymes derived from a Thermotoga sp. acetyl xylan esterase are provided in Table 1.
Thermophilic Enzymes Having Perhydrolytic Activity
As used herein, the term “thermophilic enzyme having perhydrolytic activity” or “thermophilic perhydrolase” will refer to a carbohydrate esterase family 7 enzyme (cephalosporin deacetylases and acetyl xylan esterases) having perhydrolytic activity wherein the present heat-treatment process does not significantly impact the perhydrolytic activity of the enzyme. In one embodiment, the enzyme catalyst will be considered temperature stable (i.e., “a thermophilic enzyme”) if subjecting the enzyme to the conditions of the second heat treatment step (i.e., exposure to an elevated temperature for a defined period of time) do not adversely impact the perhydrolytic activity of the enzyme. In another embodiment, the enzyme catalyst may be considered “temperature stable” (i.e., thermophilic) if exposure of the enzyme to a heat treatment period of 5 minutes to 4 hours at a temperature ranging from 75° C. to 85° C. does not significantly decrease the perhydrolytic activity of the enzyme.
In one embodiment, the thermophilic enzyme having perhydrolytic activity is an acetyl xylan esterase derived from a thermophilic microorganism, such as a species within the bacterial genus Thermotoga . In a further preferred embodiment, the thermophilic enzyme may be a variant of an acetyl xylan esterase from a thermophilic microorganism so long as the variant retains perhydrolytic activity after exposure to the conditions used in the second heat treatment. In a further preferred aspect, the thermophilic enzyme having perhydrolytic activity is an acetyl xylan esterase or variant thereof from Thermotoga maritima, Thermotoga neapolitana, Thermotoga lettingae, Thermotoga petrophila , and Thermotoga sp. RQ2. A non-limiting list of enzymes is provided in Table 1.
In yet another embodiment, the thermophilic enzyme having perhydrolytic activity comprises an amino acid sequence selected from the group consisting of SEQ ID NOs: 2, 3, 4, 5, 6, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 24, 25, 26, 27, 28, 30, 31, 32, 33, 34, 36, 37, 38, 39, 40, 42, 43, 44, 45, and 46.
In a preferred embodiment, the thermophilic enzyme is recombinantly expressed in a microbial host cell. Examples of host strains include, but are not limited to, bacterial, fungal or yeast species such as Aspergillus, Trichoderma, Saccharomyces, Pichia, Phaffia, Kluyveromyces, Candida, Hansenula, Yarrowia, Salmonella, Bacillus, Acinetobacter, Zymomonas, Agrobacterium, Erythrobacter, Chlorobium, Chromatium, Flavobacterium, Cytophaga, Rhodobacter, Rhodococcus, Streptomyces, Brevibacterium, Corynebacteria, Mycobacterium, Deinococcus, Escherichia, Erwinia, Pantoea, Pseudomonas, Sphingomonas, Methylomonas, Methylobacter, Methylococcus, Methylosinus, Methylomicrobium, Methylocystis, Alcaligenes, Synechocystis, Synechococcus, Anabaena, Thiobacillus, Methanobacterium, Klebsiella , and Myxococcus . In a preferred embodiment, bacterial host strains include Escherichia, Bacillus , and Pseudomonas . In a further preferred aspect, the bacterial host cell is Escherichia coli.
Carboxylic Acid Ester Substrates
The CE-7 enzymes having perhydrolytic activity can use a variety of carboxylic acid ester substrates (in the presence of a suitable source of peroxygen) to produce one or more peracids, such as peracetic acid.
Examples of carboxylic acid ester substrates may include, but are not limited to:
one or more esters provided by the following formula:
[X] m R 5
wherein X=an ester group of the formula R 6 C(O)O
R 6 =C1 to C7 linear, branched or cyclic hydrocarbyl moiety, optionally substituted with hydroxyl groups or C1 to C4 alkoxy groups, wherein R 6 optionally comprises one or more ether linkages for R6=C2 to C7;
R 5 =a C1 to C6 linear, branched, or cyclic hydrocarbyl moiety optionally substituted with hydroxyl groups; wherein each carbon atom in R 5 individually comprises no more than one hydroxyl group or no more than one ester group; wherein R 5 optionally comprises one or more ether linkages;
m is an integer ranging from 1 to the number of carbon atoms in R 5 ; and
wherein said esters have solubility in water of at least 5 ppm at 25° C.
In another embodiment, R 6 is C1 to C7 linear hydrocarbyl moiety, optionally substituted with hydroxyl groups or C1 to C4 alkoxy groups, optionally comprising one or more ether linkages. In a further preferred embodiment, R 6 is C2 to C7 linear hydrocarbyl moiety, optionally substituted with hydroxyl groups, and/or optionally comprising one or more ether linkages.
As used herein, the terms “hydrocarbyl”, “hydrocarbyl group”, and “hydrocarbyl moiety” mean a straight chain, branched or cyclic arrangement of carbon atoms connected by single, double, or triple carbon to carbon bonds and/or by ether linkages, and substituted accordingly with hydrogen atoms. Such hydrocarbyl groups may be aliphatic and/or aromatic. Examples of hydrocarbyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, t-butyl, cyclopropyl, cyclobutyl, pentyl, cyclopentyl, methylcyclopentyl, hexyl, cyclohexyl, benzyl, and phenyl. In one embodiment, the hydrocarbyl moiety is a straight chain, branched or cyclic arrangement of carbon atoms connected by single carbon to carbon bonds and/or by ether linkages, and substituted accordingly with hydrogen atoms.
In another embodiment, suitable substrates also include one or more glycerides of the formula:
wherein R 1 =C1 to C21 straight chain or branched chain alkyl optionally substituted with an hydroxyl or a C1 to C4 alkoxy group and R 3 and R 4 are individually H or R 1 C(O).
In another aspect, suitable substrates may also include one or more esters of the formula:
wherein R 1 is a C1 to C7 straight chain or branched chain alkyl optionally substituted with an hydroxyl or a C1 to C4 alkoxy group and R 2 is a C1 to C10 straight chain or branched chain alkyl, alkenyl, alkynyl, aryl, alkylaryl, alkylheteroaryl, heteroaryl, (CH 2 CH 2 O) n , or (CH 2 CH(CH 3 )—O) n H and n is 1 to 10.
Suitable substrates may also include one or more acylated saccharides selected from the group consisting of acylated mono-, di-, and polysaccharides. In another embodiment, the acylated saccharides are selected from the group consisting of acetylated xylan, fragments of acetylated xylan, acetylated xylose (such as xylose tetraacetate), acetylated glucose (such as glucose pentaacetate), β-D-ribofuranose-1,2,3,5-tetraacetate, tri-O-acetyl-D-galactal, tri-O-acetyl-D-glucal, and acetylated cellulose. In a preferred embodiment, the acetylated saccharide is selected from the group consisting of β-D-ribofuranose-1,2,3,5-tetraacetate, tri-O-acetyl-D-galactal, tri-O-acetyl-D-glucal, and acetylated cellulose.
In another embodiment, suitable substrates are selected from the group consisting of: monoacetin; diacetin; triacetin; monopropionin; dipropionin; tripropionin; monobutyrin; dibutyrin; tributyrin; glucose pentaacetate; xylose tetraacetate; acetylated xylan; acetylated xylan fragments; β-D-ribofuranose-1,2,3,5-tetraacetate; tri-O-acetyl-D-galactal; tri-O-acetyl-D-glucal; monoesters or diesters of 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 2,5-pentanediol, 1,6-pentanediol, 1,2-hexanediol, 2,5-hexanediol, 1,6-hexanediol; and mixtures thereof.
In another embodiment, the carboxylic acid ester is selected from the group consisting of monoacetin, diacetin, triacetin, and combinations thereof. In another embodiment, the substrate is a C1 to C6 polyol comprising one or more ester groups. In a preferred embodiment, one or more of the hydroxyl groups on the C1 to C6 polyol are substituted with one or more acetoxy groups (such as 1,3-propanediol diacetate, 1,4-butanediol diacetate, etc.). In a further embodiment, the substrate is propylene glycol diacetate (PGDA), ethylene glycol diacetate (EGDA), or a mixture thereof.
In another embodiment, suitable substrates are selected from the group consisting of ethyl acetate; methyl lactate; ethyl lactate; methyl glycolate; ethyl glycolate; methyl methoxyacetate; ethyl methoxyacetate; methyl 3-hydroxybutyrate; ethyl 3-hydroxybutyrate; triethyl 2-acetyl citrate; glucose pentaacetate; gluconolactone; glycerides (mono-, di-, and triglycerides) such as monoacetin, diacetin, triacetin, monopropionin, dipropionin (glyceryl dipropionate), tripropionin (1,2,3-tripropionylglycerol), monobutyrin, dibutyrin (glyceryl dibutyrate), tributyrin (1,2,3-tributyrylglycerol); acetylated saccharides; and mixtures thereof.
In a further embodiment, suitable substrates are selected from the group consisting of monoacetin, diacetin, triacetin, monopropionin, dipropionin, tripropionin, monobutyrin, dibutyrin, tributyrin, ethyl acetate, and ethyl lactate. In yet another aspect, the substrate is selected from the group consisting of diacetin, triacetin, ethyl acetate, and ethyl lactate. In a most preferred embodiment, the suitable substrate comprises triacetin.
Method for Determining the Concentration of Peroxycarboxylic Acid and Hydrogen Peroxide.
A variety of analytical methods can be used in the present method to analyze the reactants and products including, but not limited to, titration, high performance liquid chromatography (HPLC), gas chromatography (GC), mass spectroscopy (MS), capillary electrophoresis (CE), the analytical procedure described by U. Karst et al. ( Anal. Chem., 69(17):3623-3627 (1997)), and the 2,2′-azino-bis(3-ethylbenzothazoline)-6-sulfonate (ABTS) assay (S. Minning, et al., Analytica Chimica Acta 378:293-298 (1999) and WO 20041058961 A1) as described in U.S. Patent Application Publication No. 2008-0176783.
Recombinant Expression of a Perhydrolytic Enzyme
A variety of culture methodologies may be applied to produce the perhydrolase catalyst. Large-scale production of a specific gene product over expressed from a recombinant microbial host may be produced by batch, fed-batch or continuous culture methodologies. Batch and fed-batch culturing methods are common and well known in the art and examples may be found in Thomas D. Brock in Biotechnology: A Textbook of Industrial Microbiology , Second Edition, Sinauer Associates, Inc., Sunderland, Mass. (1989) and Deshpande, Mukund V., Appl. Biochem. Biotechnol., 36:227 (1992).
In one embodiment, commercial production of the desired perhydrolase catalyst is accomplished with a continuous culture. Continuous cultures are an open system where a defined culture media is added continuously to a bioreactor and an equal amount of conditioned media is removed simultaneously for processing. Continuous cultures generally maintain the cells at a constant high liquid phase density where cells are primarily in log phase growth. Alternatively, continuous culture may be practiced with immobilized cells where carbon and nutrients are continuously added and valuable products, by-products or waste products are continuously removed from the cell mass. Cell immobilization may be performed using a wide range of solid supports composed of natural and/or synthetic materials.
Recovery of the desired perhydrolase catalyst from a batch or fed-batch fermentation, or continuous culture may be accomplished by any of the methods that are known to those skilled in the art. For example, when the enzyme catalyst is produced intracellularly, the cell paste is separated from the culture medium by centrifugation or membrane filtration, optionally washed with water or an aqueous buffer at a desired pH, then a suspension of the cell paste in an aqueous buffer at a desired pH is lysed or homogenized to produce a cell extract containing the desired enzyme catalyst.
When an amount, concentration, or other value or parameter is given either as a range, preferred range, or a list of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. Where a range of numerical values is recited herein, unless otherwise stated, the range is intended to include the endpoints thereof, and all integers and fractions within the range. It is not intended that the scope be limited to the specific values recited when defining a range.
General Methods
The following examples are provided to demonstrate preferred embodiments. It should be appreciated by those of skill in the art that the techniques disclosed in the examples which follow represent techniques discovered by the inventor to function well in the practice of the methods disclosed herein, and thus can be considered to constitute preferred modes for its practice. However, those of skill in the art should, in light of the present disclosure, appreciate that many changes can be made in the specific embodiments which are disclosed and still obtain a like or similar result without departing from the spirit and scope of the presently disclosed methods.
All reagents and materials were obtained from DIFCO Laboratories (Detroit, Mich.), GIBCO/BRL (Gaithersburg, Md.), TCI America (Portland, Oreg.), Roche Diagnostics Corporation (Indianapolis, Ind.) or Sigma-Aldrich Chemical Company (St. Louis, Mo.), unless otherwise specified.
The following abbreviations in the specification correspond to units of measure, techniques, properties, or compounds as follows: “sec” or “s” means second(s), “min” means minute(s), “h” or “hr” means hour(s), “μL” means microliter(s), “mL” means milliliter(s), “L” means liter(s), “mM” means millimolar, “M” means molar, “mmol” means millimole(s), “ppm” means part(s) per million, “wt” means weight, “wt %” means weight percent, “g” means gram(s), “mg” means microgram(s), “ng” means nanogram(s), “g” means gravity, “HPLC” means high performance liquid chromatography, “dd H 2 O” means distilled and deionized water, “dcw” means dry cell weight, “ATCC” or “ATCC®” means the American Type Culture Collection (Manassas, Va.), “U” means unit(s) of perhydrolase activity, “rpm” means revolution(s) per minute, “EDTA” means ethylenediaminetetraacetic acid, “slpm” means standard liters per minute, “IPTG” means isopropyl β-D-1-thiogalactopyranoside, “DTT” means dithiothreitol, “BCA” means bicinchoninic acid.
EXAMPLE 1
Cloning and Expression of Acetyl Xylan Esterase from Thermotoga maritima
A gene encoding acetyl xylan esterase from T. maritima (amino acid sequence SEQ ID NO: 8) as reported in GENBANK® (accession no. NP — 227893.1) was synthesized (DNA 2.0, Menlo Park Calif.). The gene was subsequently amplified by PCR (0.5 min at 94° C., 0.5 min at 55° C., 1 min at 70° C., 30 cycles) using primers identified as SEQ ID NO: 47 and SEQ ID NO: 48. The resulting nucleic acid product (SEQ ID NO: 49) was cut with restriction enzymes PstI and XbaI and subcloned between the PstI and XbaI sites in pUC19 to generate the plasmid identified as pSW207. A gene encoding an acetyl xylan esterase from T. maritima as reported in GENBANK® (accession no. NP — 227893.1; amino acid sequence SEQ ID NO: 8) was synthesized using codons optimized for expression in E. coli (DNA 2.0, Menlo Park Calif.). The gene was subsequently amplified by PCR (0.5 min at 94° C., 0.5 min at 55° C., 1 min at 70° C., 30 cycles) using primers identified as SEQ ID NO:50 and SEQ ID NO:51. The resulting nucleic acid product (SEQ ID NO: 52) was cut with restriction enzymes EcoRI and PstI and subcloned between the EcoRI and PstI sites in pTrc99A (GENBANK® accession no. M22744) to generate the plasmid identified as pSW228 (containing the codon-optimized T. maritima coding sequence SEQ ID NO: 7). The plasmids pSW207 and pSW228 were used to transform E. coli KLP18 (U.S. Patent Application Pub. No. 2008-0176299) to generate the strains identified as KLP18/pSW207 and KLP18/pSW228, respectively. KLP18/pSW207 and KLP18/pSW228 were grown in LB media at 37° C. with shaking up to OD 600nm =0.4-0.5, at which time IPTG was added to a final concentration of 1 mM, and incubation continued for 2-3 h. Cells were harvested by centrifugation and SDS-PAGE was performed to confirm expression of the perhydrolase at 20-40% of total soluble protein.
EXAMPLE 2
Construction of Thermotoga maritima Acetyl Xylan Esterase Variants at Residue C277
The C277 (Cys277) position of T. maritima acetyl xylan esterase was changed to each of Val, Ala, Ser and Thr using oligonucleotide primer pairs (Table 2) that were designed based on the codon optimized sequence of T. maritima acetyl xylan esterase (SEQ ID NO: 7) in the plasmid pSW228. The mutations were made using QUIKCHANGE® (Stratagene) according to the manufacturer's instructions. Amplified plasmids were treated with 1 U of Dpnl at 37° C. for 1 hour. Treated plasmids were used to transform chemically competent E. coli XL1-Blue (Stratagene). Transformants were plated on LB-agar supplemented with 0.1 mg ampicillin/mL and grown overnight at 37° C. Up to five individual colonies were picked and the plasmid DNA sequenced to confirm the expected mutations.
TABLE 2
Oligonucleotides used to change residue 277 in T. maritima .
forward 5′ to 3′
reverse 5′ to 3′
Tma_C277Vf
ggacaacatcGTG
Tma_C277Vr
TAGAAGGAGG CAC GA
(SEQ ID NO: 53)
cctccttcta
(SEQ ID NO: 54)
TGTTGTCC
Tma_C277Af
ggacaacatcGC
Tma_C277Ar
TAGAAGGAGG CGC GA
(SEQ ID NO: 55)
Gcctccttcta
(SEQ ID NO: 56)
TGTTGTCC
Tma_C277Sf
ggacaacatcTCA
Tma_C277Sr
TAGAAGGAGG TGA GA
(SEQ ID NO: 57)
cctccttcta
(SEQ ID NO: 58)
TGTTGTCC
Tma_C277Tf
ggacaacatcACC
Tma_C277Tr
TAGAAGGAGG GGT GA
(SEQ ID NO: 59)
cctccttcta
(SEQ ID NO: 60)
TGTTGTCC
EXAMPLE 3
Expression of Thermotoga maritime Acetyl Xylan Esterase Variants in E. coli KLP18
Plasmids with confirmed acetyl xylan esterase mutations were used to transform E. coli KLP18 (Example 1). Transformants were grown in LB media at 37° C. with shaking up to OD 600nm =0.4-0.5, at which time IPTG was added to a final concentration of 1 mM, and incubation continued for 2-3 h. Cells were harvested by centrifugation and SDS-PAGE was performed to confirm expression of the acetyl xylan esterase at 20-40% of total soluble protein.
EXAMPLE 4
Expression of Thermotoga Acetyl Xylan Esterase Variants in E. coli KLP18 Using 1-Liter Bioreactor
Plasmids with confirmed acetyl xylan esterase mutations were used to transform E. coli KLP18 (Example 1). Transformants were plated onto LB-ampicillin (100 μg/mL) plates and incubated overnight at 37° C. Cells were harvested from a plate using 2.5 mL LB media supplemented with 20% (v/v) glycerol, and 1.0 mL aliquots of the resulting cell suspension frozen at −80° C. One mL of the thawed cell suspension was transferred to a 1-L APPLIKON® Bioreactor (APPLIKON® Biotechnology, Foster City, Calif.) with 0.7 L medium containing KH 2 PO 4 (5.0 g/L), FeSO 4 heptahydrate (0.05 g/L), MgSO 4 heptahydrate (1.0 g/L), sodium citrate dihydrate (1.90 g/L), yeast extract (Amberex 695, 5.0 g/L), Biospumex 153K antifoam (0.25 mL, Cognis Corporation), NaCl (1.0 g/L), CaCl 2 dihydrate (0.1 g/L), and NIT trace elements solution (10 mL/L). The trace elements solution contained citric acid monohydrate (10 g/L), MnSO 4 hydrate (2 g/L), NaCl (2 g/L), FeSO 4 heptahydrate (0.5 g/L), ZnSO 4 heptahydrate (0.2 g/L), CuSO 4 pentahydrate (0.02 g/L) and NaMoO 4 dihydrate (0.02 g/L). Post sterilization additions included glucose solution (50% w/w, 6.5 g) and ampicillin (25 mg/mL) stock solution (2.8 mL). Glucose solution (50% w/w) was also used for fed batch. Glucose feed was initiated 40 min after glucose concentration decreased below 0.5 g/L, starting at 0.03 g feed/min and increasing progressively each hour to 0.04, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.12, and 0.14 g/min respectively; the rate remaining constant afterwards. Glucose concentration in the medium was monitored, and if the concentration exceeded 0.1 g/L the feed rate was decreased or stopped temporarily. Induction was initiated at OD 550 =50 with addition of 0.8 mL IPTG (0.05 M). The dissolved oxygen (DO) concentration was controlled at 25% of air saturation, first by agitation (400-1000 rpm), and following by aeration (0.5-2 slpm). The temperature was controlled at 37° C., and the pH was controlled at 6.8; NH 4 OH (29% w/w) and H 2 SO 4 (20% w/v) were used for pH control. The cells were harvested by centrifugation (5,000×g for 15 minutes) at 20 h post IPTG addition.
EXAMPLE 5
Preparation of Cell Lysates Containing Semi-Purified T. maritima Acetyl Xylan Esterase Variants
Cell cultures were grown using a fermentation protocol similar to that described in Example 4 at a 1-L scale (Applikon). Cells harvested by centrifugation at 5,000×g for 15 minutes were resuspended (20% w/v) in 50 mM phosphate buffer pH 7.0 supplemented with 1.0 mM DTT. Resuspended cells were passed through a French pressure cell twice to ensure >95% cell lysis.
EXAMPLE 6
Incubation of E. coli KLP18/psW228 Lysate Containing T. maritima Wild-type Perhydrolase for DNA Removal
A cell suspension of E. coli KLP18/psW228 (Example 1) containing the wild-type T. maritima perhydrolase was prepared by suspending 1828 grams of frozen cell paste in 50 mM phosphate buffer (pH 7.2) at a wet cell weight loading of 250 grams per liter. Aliquots of this cell suspension were treated as indicated in Table 3. To each aliquot of cell suspension was added magnesium sulfate (2 mM) prior to incubation at 50° C. for approximately 18 hours. At the conclusion of all process steps for each treatment, two 40-mL samples were centrifuged and the supernatant frozen at −80° C. Size exclusion chromatography was subsequently performed on thawed samples using the following protocol: HILOAD™ 26/60 column (GE Healthcare), SUPERDEX™ 200 prep grade packing (GE Healthcare), isocratic elution with 2.5 mL/min of 50 mM phosphate buffer (pH 7.0) at 20° C. with monitoring of the column eluent at 260, 280 and 400 nm.
TABLE 3
Process steps to produce samples for
size exclusion chromatography.
Sample
PAA961-
Step 1
Step 2
Step 3
BHF
Homogenization
—
—
BH50F
Homogenization
50° C. incubation
—
B75F
Homogenization
50° C. incubation
75° C. heat
treatment
BHQF
Homogenization
75° C. heat
—
treatment
A50HF
50° C. incubation
Homogenization
—
A75F
50° C. incubation
Homogenization
75° C. heat
treatment
Incubation was done for a period of approximately 18 hours, and heat treatment was for approximately 2 hours.
The T. maritima perhydrolase had a retention time of ca. 95 minutes, and components of the sample that eluted from the column at earlier retention times were largely composed of DNA, where the ratio of the 260 nm/280 nm absorbances was approximately 2, and where these collected fractions were analyzed by gel electrophoresis to confirm the presence of DNA.
FIGS. 1A through 1D present the chromatograms of lysate supernatants treated using four different processing steps: ( FIG. 1A ) crude lysate (no incubation or heat-treatment), ( FIG. 1B ) lysate after incubation at 50° C., ( FIG. 1C ) lysate after incubation at 50° C. followed by heat-treatment at 75° C., and ( FIG. 1D ) lysate after heat-treatment at 75° C. (no 50° C. incubation). All chromatograms have same vertical scale, from −100 to +4500 mAU. DNA components in crude lysate ( FIG. 1A ) (components with retention times less than 75-80 min) were removed by incubation at 50° C. ( FIG. 1B ), resulting in the increase in low-molecular-weight DNA fragments that had a retention time of approximately 130-140 min. There was some additional purification of the lysate by the combination of incubation at 50° C. followed by heat-treatment at 75° C. ( FIG. 1C ), whereas a significant amount of DNA remained in the lysate that was heat-treated at 75° C. without prior incubation at 50° C.
The incubation step was not effective in removing DNA when performed prior to homogenization of the E. coli cells containing the perhydrolase. FIGS. 2A through 2C present chromatograms for samples that were prepared according to the following procedures: ( FIG. 2A ) homogenization followed by incubation at 50° C., ( FIG. 2B ) incubation of a cell suspension at 50° C. followed by homogenization, and ( FIG. 2C ) incubation at 50° C. followed by homogenization and subsequent heat treatment at 75° C.; incubation prior to homogenization was not effective for DNA removal (see FIG. 2B and FIG. 2C ).
EXAMPLE 6
Incubation of E. coli KLP18 lysate containing T. maritima C277S perhydrolase variant for DNA removal
The procedure described in Example 5 was repeated using an incubation temperature of 45° C. and a lysate of E. coli KLP18 containing T. maritima C277S perhydrolase (See Examples 2 and 3; SEQ ID NO: 11). Chromatographic analysis of lysate supernatants after (1) no incubation, (2) incubation at 45° C. with no added magnesium sulfate, and (3) incubation at 45° C. with 2 mM magnesium sulfate was performed. DNA components in crude lysate (components with retention times less than 75-80 min) were removed by incubation at 45° C., resulting in the increase in low-molecular-weight DNA fragments that had a retention time of approximately 130-140 min. A sample component at 50 min that adsorbed at 400 nm was a not a DNA component.
EXAMPLE 7
Two-Stage Heat Treatment of Cell Lysates Containing T. maritima Acetyl Xylan Esterase Variants
The effect of incubation time and temperature, as well as heat-treatment temperature on reduction of DNA concentration in E. coli cell homogenates containing perhydrolase was examined by performing the two-stage heat treatment study outlined in Table 4, below. A 50-mL aliquot of homogenate was placed in a 125-mL sterile disposable shake flask and placed in a shaking incubator for the Stage 1 heat treatment (incubation) for either 8 h or 16 h. At the conclusion of the first stage, the flask was transferred to a shaking water bath at the elevated Stage 2 temperature for 2 h. The resulting perhydrolase-containing mixtures were clarified by centrifugation prior to analysis.
TABLE 4 Matrix flsk Stage 1 Heat Treat. Stage 2 Heat Treat. ID # Temp, ° C. Time, hr Temp, ° C. Time, hr 8-75 1 45 8 75 2 2 50 8 75 2 3 55 8 75 2 8-80 4 45 8 80 2 5 50 8 80 2 6 55 8 80 2 8-85 7 45 8 85 2 8 50 8 85 2 9 55 8 85 2 16-75 10 45 16 75 2 11 50 16 75 2 12 55 16 75 2 16-80 13 45 16 80 2 14 50 16 80 2 15 55 16 80 2 16-85 16 45 16 85 2 17 50 16 85 2 18 55 16 85 2
Protein concentration of the final heat treated supernatant was primarily a function of the Stage two heat-treatment temperature with more E. coli protein precipitated as Stage two temperature increased.
Total activity as pNPA units per g (mL) of clarified supernatant after two-stage heat-treatment is reported in Table 5.
TABLE 5
Temp
Time
Temp
Time
pNPA,
Calculated
Sample
1
1
2
2
BCA
U/mg
pNPA
#
(° C.)
(hr)
(° C.)
(hr)
(mg/g)
protein
(U/g)
1
45
8
75
2
8.76
121.3
1062.5
4
45
8
80
2
7.31
124.2
907.6
7
45
8
85
2
6.97
129.7
903.8
10
45
16
75
2
8.08
127.7
1032.2
13
45
16
80
2
7.34
136.2
999.7
16
45
16
85
2
6.94
137.0
951.0
2
50
8
75
2
9.16
104.6
958.2
5
50
8
80
2
7.65
122.3
935.3
8
50
8
85
2
6.95
137.9
958.6
11
50
16
75
2
8.88
122.7
1089.6
14
50
16
80
2
8.48
111.9
948.9
17
50
16
85
2
7.15
129.8
928.3
3
55
8
75
2
8.47
113.4
960.5
6
55
8
80
2
7.58
124.0
939.8
9
55
8
85
2
7.09
126.7
898.1
12
55
16
75
2
8.78
105.7
927.8
15
55
16
80
2
8.31
109.2
907.5
18
55
16
85
2
7.17
119.5
856.5
Two-stage heat treatment conditions that resulted in the highest specific activity (U/mg protein) did not also produce the highest total activity per weight (volume) of treated supernatant; Stage 1 at 45° C. or 50° C. for 16 hours with a Stage 2 treatment of 2 hours at 75° C. produced the highest total pNPA activity, as did 45° C. for 8 hours followed by 75° C. for 2 hours.
SEC chromatograms demonstrate the production of eluents that partially co-elute with the perhydrolase (the peak in the 82-mL to 86-mL fractions) when the 1 st stage temperature was 55° C. and the 2 nd stage treatment was 75° C. for 2 h. The best resolution was at a 1 st stage temperature of 45° C.; there is still resolution is at 50° C., but the perhydrolase peak is unresolved at 55° C. ( FIGS. 3 , 4 , and 5 , respectively). For comparison, the SEC chromatogram of unheated cell homogenate is illustrated in FIG. 6 , where DNA elutes in the 42-mL to 46-mL fractions.
The SEC chromatograms for the remaining conditions for heat treatment outlined in Table 5 appear in FIGS. 7 through 21 , all demonstrating reduction in DNA at fractions 42-mL to 46-mL, and resolved perhydrolase at fractions 82-mL to 86-mL.
The results of two additional control experiments illustrating the effect of a single-stage heat treatment for 2 hours at 75° C. or 85° C. are provided in the SEC chromatograms of FIGS. 22 and 23 , respectively. A significant amount of DNA remained after single-stage heat treatment at 75° C. or 85° C. for 2 hrs.
EXAMPLE 8
Filtration of Heat-treated E. coli Cell Homogenates Containing T. maritima C277S Perhydrolase Variant
A homogenate of E. coli KLP18/pSW228/C277S containing T. maritima C277S perhydrolase variant (9.9 mg/mL total protein by BCA protein assay) was prepared using a dairy homogenizer operating at 12,000 psig (approximately 82/4 MPa), the pH of the homogenate was adjusted to pH 7.3, and magnesium sulfate (2 mM) was added. The resulting homogenate was divided into to five aliquots (A-E; 250-mL aliquots) and treated as follows: (A) incubated at 50° C. for 16 h with slow mixing, (B) incubated 50° C. for 5 h with slow mixing, (C, control) added DNAse to 0.5 mg per liter and incubated 50° C. for 5 h with slow mixing, (C, control) added DNAse to 0.5 mg per liter and incubated 50° C. for 16 h with slow mixing, (E, control) no heat treatment of homogenate. For control reactions containing DNAse (DN25, Sigma/Aldrich), a DNAse solution was prepared as 1 mg/mL in KPB buffer (25 mM, pH 7.0) containing 5 mM MgSO 4 : Samples of each homogenate were first clarified by centrifugation then filtered for 2 min using a Nanosep 0.2 micron spin filter (PALL), and the percentage of fitrate recovered compared to starting homogenate was determined. Incubation for 5 h at 50° C. produced a significant improvement in filterability of the homogenate when compared to no heat treatment at 50° C., and no significant improvement in filterability was obtained when 0.5 mg/L DNAse was added to the homogenate prior to heat treatment (Table 6).
TABLE 6
filtrate
aliquot
treatment
(wt %)
E
none
33
A
16 h incubation at 50° C.
84
B
5 h incubation at 50° C.
77
C
5 h incubation at 50° C. with
82
0.5 mg/L DNAse
D
16 h incubation at 50° C. with
82
0.5 mg/L DNAse
EXAMPLE 9
Filtration of Heat-treated E. coli Cell Homogenates Containing T. maritima C277S Perhydrolase Variant
The procedure described in Example 8 was repeated using temperatures and incubation times are described in Table 7; control reactions were run by adding 0.5 mg/L DNAse to the homogenate prior to incubation. Filtration results obtained using the protocols in Table 7 are reported in Tables 8 and 9. A control experiment was performed by first heat-treating an aliquot of the homogenate at 81° C. for 1 h, then cooling to 50° C. and incubating for 5 h or 21 h with or without added DNAse to demonstrate the significantly lower filterability of homogenate that is subjected to a single stage heat treatment at high temperature when compared to incubation at 50° C. (Table 10).
TABLE 7
Heat-treatment protocols.
aliquot
temp (° C.)
DNAse
Time, hr
A
30
−
5 or 21
B
30
+
5 or 21
C
40
−
5 or 21
D
40
+
5 or 21
E
50
−
5 or 21
F
50
+
5 or 21
G
60
−
5 or 21
H
60
+
5 or 21
I
70
−
5 or 21
J
70
+
5 or 21
K
50
−
5 or 21
L
50
+
5 or 21
TABLE 8
Filtration results of homogenate after incubation for 5
hr at various temperatures with and without added DNAse.
%
Treatment
filtrate
std dev
0 hr
4.9
1.36
30° C.
9.1
0.51
30° C. with DNAse
68.3
1.37
40° C.
44.3
6.17
40° C. with DNAse
32.9
6.76
50° C.
80.6
13.66
50° C. with DNAse
89.8
0.96
60° C.
18.7
0.57
60° C. with DNAse
48.4
0.96
70° C.
23.1
2.59
70° C. with DNAse
61.2
17.54
TABLE 9
Filtration results of homogenate after incubation for 21
hr at various temperatures with and without added DNAse.
%
aliquot
filtrate
std dev
0 hr
4.9
1.36
30° C.
34.5
5.56
30° C. with DNAse
20.5
13.58
40° C.
74.1
2.15
40° C. with DNAse
83.8
0.78
50° C.
73.3
1.23
50° C. with DNAse
69.3
6.55
60° C.
58.4
48.62
60° C. with DNAse
48.8
1.60
70° C.
27.5
0.55
70° C. with DNAse
53.1
0.48
TABLE 10
Filtration results of heat-treated homogenate (81°
C., 1 hr) with subsequent incubation for 5 hr or
21 hr at 50° C. with and without added DNAse.
%
Treatment
filtrate
std dev
0 hr
1.4
1.4
50° C., 5 hr
13.7
13.7
50° C., 5 h with DNAse
1.0
1.0
50° C., 21 hr
1.5
1.5
50° C., 21 hr with DNAse
0.7
0.7
|
A two-stage heat treatment process is provided to improve the processability of recombinant microbial biomass comprising an enzyme having perhydrolytic activity. More specifically, a process is provided to treat the recombinant microbial biomass comprising a Thermotoga sp. acetyl xylan esterase having perhydrolytic activity such that microfiltration may be used to partially-purify and/or concentrate protein preparations. The acetyl xylan esterase may be used to produce peroxycarboxylic acids suitable for use in a variety of applications such as cleaning, disinfecting, sanitizing, bleaching, wood pulp processing, and paper pulp processing applications.
| 2
|
CROSS REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of application Ser. No. 07/732,844 filed Jul. 19, 1991, now abandoned.
BACKGROUND OF THE INVENTION
1. Field Of the Invention
This invention is directed to film-forming compositions for enveloping solid forms, particularly seeds. In another aspect, the invention relates to a process for enveloping with the aid of these compositions. In a further aspect, the invention is concerned with the seeds coated with the compositions of this invention.
Seeds are treated to promote good seedling establishment, to minimize yield loss, to maintain and improve the quality of the seeds and to avoid the spread of harmful organisms.
Other benefits derived from seed treatments include improved adhesion of any pesticidal formulation, the ability to maintain the distribution of said pesticides during the application of the treatment, improving the flow of seeds during treatment, enhancement of the appearance and perceived quality of the seeds, and greatly reducing the potential hazards from dust during treating and handling. Biological considerations for seed coatings include that the pesticides should: be consistently effective under various environmental conditions; be safe to operators during handling and sowing; be safe to wildlife; have a wide safety margin between the dose that controls harmful organisms and the dose that harms the plant; be compatible with other materials used on the seed; and not produce harmful residues in the plant or soil.
Protection of seeds and young seedlings from soil-borne pests during the early stages of plant growth is the main purpose of seed treatment. The use of fungicides and insecticides for protecting seeds and seedlings against seed and soil-borne diseases is well known and widely used. There is also the desire to develop systems containing biologically active materials and to exploit the potential of the seed as a carrier for highly targeted materials such as microorganisms, trace elements, growth regulators, and the like.
Successful and practical seed treatments should satisfy a range of commercial requirements. For example, the treatment should provide effective delivery of any active ingredient contained therein. As another example, the physico-chemical characteristics of the formulation should facilitate application to and retention on the seeds.
Additionally, a coloring agent, such as a dye is required by law in the seed coating so that an observer can immediately determine that the seeds are treated. The dye is also useful to indicate to the user the degree of uniformity of the coating applied.
It is therefore an object of this invention to provide a film-forming composition for seed coating. It is a further object of their invention to provide a seed coating composition with properties greater than any of the individual components of the composition.
It is a further object of this invention to provide a method for effectively coating seeds with this film forming composition. It is still a further object of this invention to provide final seed products obtained and coated with these compositions.
2. Description of Related Art
U.S. Pat. Nos. 4,513,019 and 4,576,646 describe a process for enveloping objects such as seeds with a composition comprising a cellulosic film-forming substance, at least one alpha-cellulose, and a suitable plasticizer.
U.S. Pat. No. 4,543,370 describes a seed coating composition which includes cellulosic film-forming polymer, a pigment, a plasticizer, and optionally, a colloidal silica and a surfactant.
British Patent No. 2,040,684A describes a method and a composition for treating seeds including an active pesticide and adhesive sticker in admixture with suspending agents, surface active agents, and other adjuvants, applied to seeds to yield seeds with an adherent coating in which active pesticidal agent is dispersed.
SUMMARY OF THE INVENTION
It has been found that when certain water soluble, film-forming polymers are combined in definite proportions, the resulting polymer mixture possesses improved properties when used for seed coating applications. The seed coating composition has film properties that are superior to those of the individual components of the composition.
The film-forming compositions for coating objects such as seeds according to the current invention comprise a cellulosic polymer and a plasticizer. The plasticizer is selected from the group consisting of polyalkylene oxide polymers having a viscosity average molecular weight of at least about 150,000 and polyalkylene alcohols. Particularly, the film-forming compositions of the present invention comprise from 33 to 85 percent as dry weight of a cellulosic polymer and from 16 to 66 percent as dry weight of a plasticizer. The present compositions are substantially free from alpha-cellulose.
The compositions of this invention may also include a glycol, microbial agents, gelling agents, surfactants, or antifoamants in an aqueous medium.
A process for enveloping solid forms such as seeds with the above composition is also embraced by the present invention. It is intended that the composition will be mixed with seed protectant chemicals, such as fungicides, prior to its application to seeds in seed treating equipment. The final product, consisting of coated seeds, is also embraced by the current invention.
DETAILED DESCRIPTION OF THE INVENTION
The film-forming compositions of the present invention contain: a) from 33 to 85 percent as dry weight of a cellulosic polymer; and b) from 15 to 66 percent as dry weight of a plasticizer, preferably a polyalkylene oxide polymer or polyalkylene alcohol. The preferred weight ratio of cellulosic polymer to polyalkylene oxide polymer is between 1:2 and 6:1. A more preferred ratio is between 4:1 and 5:1.
To this formulation may be added a glycol, preferably selected from the group of dialkylene glycols including, for example, diethylene glycol, dipropylene glycol and the like. Other compounds which may be present include gelling agents such as hydrous magnesium aluminum silicates, surfactants such as ethoxylated alkyl phenol, and antifoam agents such as silicone dispersions. Normally these additional, optional components are each present in an amount up to ten percent based on the total composition. Additionally, an effective amount of one or more active ingredients, for example, microbial agents such as benzisothiazolinone, fungicides or other chemical protectants, may be included in the seed-coating composition. The amount of active ingredient employed may vary widely depending on the nature of the active ingredient. When used, the active ingredient may be present in an amount ranging from trace amounts, i.e., less than 0.5 percent, up to fifty percent based on the total composition.
The composition can be dissolved or dispersed in water, and if needed, surfactants, clays, mica, and dyes may be added to obtain a desired appearance.
Cellulosic polymers suitable for use in the present film-forming compositions are the hydroxyalkyl ethers of cellulose, preferably, hydroxyalkyl methylcellulose, i.e., hydroxymethyl methylcellulose, hydroxyethyl methylcellulose, and hydroxypropyl methylcellulose. Other suitable cellulosic polymers include the monocarboxylic esters of cellulose, i.e., cellulose acetate; and the mixed ether-esters of cellulose. A preferred selection from this group is hydroxypropyl methylcellulose. Preferably, the cellulosic polymer is substantially free from alpha-cellulose and sodium carboxymethyl cellulose.
A plasticizer will be used with the cellulosic film-forming substance. The main function of the plasticizer is as a cooperative film-forming agent, binder, and plasticizer, to modify the suppleness and strength of the films made with the cellulosic substances.
Among the plasticizers that may be used in the present film-forming compositions are polyalkylene oxide polymers having a viscosity average molecular weight of at least about 150,000. In preferred embodiments, the viscosity average molecular weight of the polyalkylene oxide polymer ranges from about 150,000 to about 6,000,000. More preferably, the viscosity average molecular weight ranges from about 200,000 to about 1,000,000, most preferably, from about 200,000 to about 300,000. Suitable non-limiting examples of polyalkylene oxide polymers are polyethylene oxide polymers and polypropylene oxide polymers. Preferably, the polyalkylene oxide polymer is a polyethylene oxide polymer. A suitable source of polyethylene oxide polymer is POLYOX™ brand polyethylene oxide polymer available from Union Carbide Corporation.
The preferred polyethylene oxide polymer of this invention, also known as a poly(ethylene oxide) resin, may be represented by the formula:
--(O--CH.sub.2 --CH.sub.2 --).sub.x
wherein x may be a variety of numbers such that the viscosity average molecular weight of the polymer is at least about 150,000. Because of the high molecular weight of these kinds of resins, the concentration of reactive end groups is extremely small, and therefore, typically essentially no end-group reactivity is observed.
The polyalkylene oxide polymers of this invention are to be distinguished from polyalkylene glycols, such as polyethylene glycol (PEG). The glycols are characterized as having a number average molecular weight ranging from as low as 200 to about 20,000. Polyalkylene glycols contain hydroxyl end-groups, the concentration of which is large enough such that end-group reactivity of these compounds is typically observed.
Alternatively, a polyalkylene alcohol may be employed as a plasticizer in the composition and process of this invention in place of the polyalkylene oxide polymer. Suitable nonlimiting examples of polyalkylene alcohols include polyvinyl alcohol, polypropylene alcohol and the like. Preferably, the polyalkylene alcohol is polyvinyl alcohol. Typically, the viscosity average molecular weight of the polyalkylene alcohol is at least about 100,000. Preferably, the viscosity average molecular weight ranges from about 100,000 to about 300,000, more preferably, to about 220,000. In further preferred embodiments, from about 80 to about 99 percent of the polyalkylene alcohol is alcoholized.
If the addition of secondary binders is desired at the discretion of the formulator, the following are some possibilities: polyvinyl pyrrolidone, sodium carboxymethyl cellulose, or any of a number of latexes commercially available for this purpose.
The compositions according to the invention may further comprise the additives conventionally used for modifying the properties of the coating material, such as color, speed of dissolution in various media, and for protecting the material from damage from the environment, such as anti-oxidants and ultra-violet light protectors. Glycol substances, such as dipropylene glycol, may be added for anti-freeze protection in colder climates. Materials that may be added to obtain a desired appearance include clays, mica and dyes.
The viscosity of the present seed-coating compositions at application should be between about 300 and 2000 centipoise, with a preferred performance viscosity of about 900 centipoise. The effective amount of seed coating composition per 100 pounds of seeds may range between 4 and 8 ounces.
Among the seeds that can be coated successfully with the present compositions are soybean, sunflower, corn, peas, and rape seed, but the application of the compositions is not limited to these seeds.
A principal feature of this film-forming composition is that it provides a seed coating with increased elasticity. Reduced brittleness results in decreased dustiness and the subsequent elimination of related dust problems. Elimination of the dust associated with many seed treatments also eliminates the associated health hazards to those who work with treated seeds, such as processing plant employees, truck drivers, warehouse workers, and farmers.
Another advantageous feature provided by the coating is a reduction in seed splitting or cracking, resulting in increased germination of the treated seeds. The film forming composition of this invention also allows for filling in of the natural cracks in older seeds, which leads to an increase in germination.
Still another advantage of this invention is the uniform coating of-seeds with non-dusting seed treatment which will not interfere with germination and sprouting of the seed but which will protect the seed against seed-borne pathogens.
A further advantage afforded by this invention is a method of treating seeds which will materially reduce the quantity of treatment applied to the seed, and thereby reducing the cost of seed treatment.
The preferred process for making a coating using film-forming compositions according to the present invention consists of dissolving or dispersing the various ingredients of the mixture in a suitable solvent, such as an aqueous medium, then in spraying the solution or suspension obtained onto the previously prepared substrates. The aqueous solutions or dispersions may attain concentrations of up to 25% by weight of the film-forming composition of this invention, the remainder of the solution being solvent. The films so obtained are quite adherent to the substrates. Consequently, they provide excellent resistance to abrasion or to peeling at the edges. The hardness of the cores of the substrates is also increased and therefore made more durable and resistant to damage.
The choice of the particular film-forming composition used and the additives chosen will depend on the application and use of the seed substrate. For example, an effective protection against dampness may be obtained while maintaining or improving the germinative properties of the seeds when a coating designed for low temperature is used.
The following examples are illustrative of the composition and process of this invention, but should not be construed to be limiting thereof. In all of the examples which follow, POLYOX WR PA 3154 brand polyethylene oxide polymer is employed. That polymer resin is characterized by a viscosity average molecular weight ranging between 200,000 and 300,000.
EXAMPLE 1
775 g of hydroxypropyl methycellulose (HMPC) (Methocel E6, trademark of the Dow Corporation) and 155 g of polyethylene oxide polymer (Polyox WR PA 3154, trademark Union Carbide Corporation) were added to 7,750 g of water under agitation until a complete dissolution was obtained. This was completed in about four hours. To this solution was added 100 g of dipropylene glycol, 25 g of clay and 25 parts of a surfactant. The resulting semi-transparent liquid had a viscosity of 900 cps.
A thin film of this material was drawn on a glass slide which, after drying, gave an elastic, non-brittle, translucent film which did not cling to the glass and was easily peeled off. By contrast, either of the polymers alone, when prepared in the same way, gave films which were more brittle and were not readily peeled from the glass.
Four ounces of this material was mixed with 4 ounces of a fungicide, Vitavax® (trademark, Uniroyal Chemical Company) and one-half ounce of a colorant, Pro-ized® pigment (trademark, Gustafson, Inc.) dispersion and applied to 100 lbs of soybean seeds. For this purpose a commercial 6-foot film treater was used.
The coated seeds were compared for dust-off and showed no dust when compared to seeds coated with fungicide alone. The coated seeds were smooth, shiny, and red.
The measurement for dustiness used and several comparative examples follow. The method entails agitating 40 grams of seeds by air jet and the dust collected on filter paper and is weighed on an analytical balance. The dust test demonstrates a comparison of how a seed treatment chemical adheres to the seed. The lower dust level indicates a more effective seed coating.
Table I indicates the amount of dust generated by each seed treatment or lack thereof.
TABLE I______________________________________Type of Seed Treatment Dust Weight (mg)______________________________________Untreated 1.5Vitavax ® 200 FF Red.sup.1 0.4Composition of Example #1 0.0Vitavax ® + Seperit 2039.sup.2 0.8Vitavax + Methocel E6 1.1Vitavax + Polyox WPRA 1.0______________________________________ Notes for Table I: .sup.1 Vitavax 200 FF red is a commercially available coating formulation from Uniroyal Chemical Company. .sup.2 Seperit is a trademark of the Seppic Corporation. .sup.3 Methocel E6 was applied 6% by weight and was prepared as described above for Example 1. .sup.4 Polyox WRPA was applied 5% by weight and was prepared as in Exampl 1.
It is apparent from the above dustiness data that the composition of Example 1 is much better than either the untreated seeds of the commercially available coated seeds. For comparative purposes, the seeds were coated with each of the film-forming polymers which together comprise the coating of Example 1. The data shows that each of these materials taken separately result in poor performance regarding dustiness. Their combination results in the surprising efficacy of the composition of Example 1.
EXAMPLE 2
Twelve grams of hydroxypropyl methylcellulose (HPMC) (Methocel E-6) and 12 g of polyethylene oxide polymer (Polyox WR PA 3154) were added to 300 g of water at 50/C. The mixture agitated for 1 hour in a glass beaker to obtain a hazy solution was mixed with Vitavax 200 FF red in the ratio of 1:1 to obtain a slurry of about 700 cps viscosity. Eight ounces of the above composition was applied to 100 pounds of soybean seeds. These seeds were similar to those of Example 1 both in quality and appearance.
EXAMPLE 3
Fifty grams of hydroxypropyl methylcellulose (HPMC) and 20 g of polyethylene oxide polymer (Polyox WR PA 3154) were mixed in a Waring blender for 5 minutes to obtain a homogeneous mixture. The mixture was then dispersed in 800 grams of water. To this was added 50 parts of dipropylene glycol, 50 grams of surfactant (Armul 1310, trademark, DeSoto Company), 50 grams of Min-u-gel PC (trademark, Floridan Company), and a colorant (Pro-ized colorant, trademark, Gustafson, Inc.) which was predispersed in 100 grams of water. This gave a translucent polymer dispersion which was applied to sunflower seeds at the rate of 8 ounces per 100 lbs of seeds. The treatment resulted in very smooth and shiny coatings on the sunflower seeds.
EXAMPLE 4
Thirty five grams of hydroxypropyl methylcellulose (HPMC) (Methocel E6) and 60 g of polyethylene oxide polymer (Polyox WR PA 3154) were dispersed in 900 grams of water under agitation to obtain a solution. This solution was mixed in a 1:1 ratio with a fungicide (Captan, trademark of Gustafson, Inc.) and applied to corn seeds at the rate of 8 ounces per 100 lbs of seeds in a glass jar that was manually shaken. The resulting seeds were evenly covered with the coating composition. When Captan alone was applied to the seeds, the depressed part of the seed remained uncoated and the seeds were not uniform in appearance or coverage.
EXAMPLE 5
Pilot Plant Production
Into a 150 gallon mixing vessel is pumped 733.48 lbs. of water and 0.27 lbs. of an antifoam agent (Antifoam FG-10, trademark Dow Corning Company). Heat is then applied with slow agitation to raise the water temperature to about 60/C. When this temperature is attained the speed of the propeller is increased.
The heat pump is then turned off and 71.25 lbs. of hydroxypropyl methylcellulose (Methocel E-6, trademark of the Dow Company) is added over a time period of 1/2 to 3/4 hours in manageable portions. Care must be taken not to add this too quickly because excessive frothing will result.
14.65 lbs. of polyethylene oxide polymer (Polyox WR PA 3154, trademark of the Union Carbide Company) is added with good agitation for 15 minutes and allowed to disperse well. A thorough dispersion will require one or two hours. 96.92 lbs. of dipropylene glycol, 1.00 lb. of microbial agent (Proxel GXL, trademark of ICI Americas, Inc.), 4.40 lbs. of gelling agent (Min-U-Gel, trademark of the Floriden Co.), and 20.81 lbs. of surfactant (Armul 1310, trademark of DeSoto, Inc.) are added, and agitation continued for one or two hours more.
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Film-forming compositions for coating objects, such as seeds, are characterized by a cellulosic polymer, and a polyalkylene oxide polymer. The compositions may also include a glycol, microbial agents, gelling agents, surfactants, and antifoamants in an aqueous medium.
In a process for enveloping solid forms such as seeds with the above composition, the composition may be mixed with seed protectant chemicals, such as fungicides, prior to its application to seeds in seed treating equipment.
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[0001] This application is a Divisional of pending patent application Ser. No. 11/173,561, filed Jul. 1, 2005, the entire disclosure of which is incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates to a method and apparatus for utilizing a spin forming tool to form a distinct geometric shape in a container end closure which is adapted for interconnection to a container neck and which has improved strength and buckle resistance.
BACKGROUND OF THE INVENTION
[0003] Containers, and more specifically metallic beverage containers, are typically manufactured by interconnecting a beverage can end closure on a beverage container body. In some applications, an end closure may be interconnected on both a top side and a bottom side of a can body. More frequently, however, a beverage can end closure is interconnected on a top end of a beverage can body which is drawn and ironed from a flat sheet of blank material such as aluminum. Due to the potentially high internal pressures generated by carbonated beverages, both the beverage can body and the beverage can end closure are typically required to sustain internal pressures exceeding 90 psi without catastrophic and permanent deformation. Further, depending on various environmental conditions such as heat, over fill, high CO2 content, and vibration, the internal pressure in a typical beverage can may at times exceed 100 psi. Thus, beverage can bodies and end closures must be durable to withstand high internal pressures, yet manufactured with extremely thin and durable materials such as aluminum to decrease the overall cost of the manufacturing process and the weight of the finished product.
[0004] Accordingly, there exists a significant need for a durable beverage container end closure which can withstand the high internal pressures created by carbonated beverages, and the external forces applied during shipping, yet which is made from a durable, lightweight and extremely thin metallic material with a geometric configuration which reduces material requirements. Previous attempts have been made to provide beverage container end closures with unique geometric configurations to provide material savings and improve strength. One example of such an end closure is described in U.S. Pat. No. 6,065,634 To Crown Cork and Seal Technology Corporation, entitled “Can End and Method for Fixing the Same to a Can Body”. Other inventions known in the art have attempted to improve the strength of container end closures and save material costs by improving the geometry of the countersink region. Examples of these patents are U.S. Pat. No. 5,685,189 and U.S. Pat. No. 6,460,723 to Nguyen et al, which are incorporated herein in their entirety by reference. Another pending application which discloses other improved end closure geometry is disclosed in pending U.S. patent application Ser. No. 10/340,535, which was filed on Jan. 10, 2003 and is further incorporated herein in its entirety by reference. Finally, the assignee of the present application owns another pending application related to reforming and reprofiling a container bottom, which is disclosed in pending U.S. patent Ser. No. 11/020,944 and which is further incorporated herein by reference in its entirety.
[0005] The following disclosure describes an improved container end closure which is adapted for interconnection to a container body and which has an improved countersink, chuck wall geometry, and unit depth which significantly saves material costs, yet can withstand significant internal pressures.
[0006] Previous methods and apparatus used to increase the strength of a container end closure have generally been attempted using traditional forming presses, which utilize a sequence of tooling operations in a reciprocating press to create a specific geometry. Unfortunately with the use of small gauge aluminum and other thin metallic materials, it has become increasingly difficult to form a preferred geometry without quality control issues as a result of the physical properties of the end closure and the difficulty of retaining a desired shape. Furthermore, when a thin metallic material is worked in a traditional forming press, certain portions of the end closure may be thinned, either from stretching, bending operations, commonly known as “coining”. When excessive thinning occurs, the overall strength and integrity of the end closure may be compromised. Further, it is practically impossible to form certain geometries with a typical die press. Thus, there is a significant need in the industry for a new method and apparatus for forming a preferred shape in an end closure, and which uses rollers and other mechanical devices which can form a preferred shape in the end closure without requiring traditional forming presses and the inherent problems related thereto.
[0007] Furthermore, new end closure geometries are needed which have distinct shapes and provide superior strength and buckle resistance when interconnected to pressurized containers. As previously mentioned these geometries are typically not feasible using traditional end closure manufacturing techniques. Thus, there is a significant need for new end closure geometries which have improved strength characteristics and which are capable of being formed with thin walled metallic materials.
SUMMARY OF THE INVENTION
[0008] It is thus one aspect of the present invention to provide an improved method and apparatus for forming one or more reinforcing beads or other geometric shapes in a container end closure. Thus, in one aspect of the present invention, one or more shaping rollers are utilized to spin-form a portion of an interior or exterior wall portion of a chuck wall or an end closure countersink to provide improved strength characteristics and potential material savings. As used herein, the term “spin-form” may also be referred to as “reform” or “reprofile” and may generally be defined as a process to alter the geometric profile of a container end closure. In one embodiment, a method for changing the geometry of a metal end closure is provided, comprising:
[0009] A method for creating a preferred geometry of a metallic end closure which is adapted for interconnection to a neck of a container, comprising:
[0010] a) providing a metallic end closure comprising a peripheral cover hook, a chuck-wall extending downwardly therefrom, a countersink having an outer panel wall interconnected to a lower end of the chuck wall, and an inner panel wall interconnected to a central panel;
[0011] b) providing a shaping tool which rotates around a central axis, said shaping tool in having an outer surface with a predetermined shape;
[0012] c) positioning said outer surface of said shaping tool in contact with at least one of the inner panel wall, the outer panel wall and the chuck wall, wherein a predetermined shape is created in said end closure when said shaping tool engages said metallic end closure.
[0013] In another aspect of the present invention the shaping rollers are interconnected to an apparatus which rotates about a given axis which allows the shaping rollers to be positioned against the end closure to create a preferred shape. Alternatively, the end closure is rotated about one or more shaping rollers, which are substantially stationary. Thus, it is another aspect of the present invention to provide an apparatus for forming a preferred geometry in a metallic end closure by utilizing a tool which rotates around a substantially stationary end closure, comprising:
[0014] a means for retaining said end closure in a substantially stationary position;
[0015] a container spin-forming assembly comprising a roller block aligned in opposing relationship to the end closure, said roller block having an outer annular edge and a leading surface;
[0016] a rotating means for rotating said spin-forming assembly;
[0017] a pair of reform rollers which project outwardly from said roller block leading surface and which are operably sized to engage an inner panel wall of the end closure of the container; and
[0018] a biasing means operably interconnected to said pair of reform rollers, wherein when a force is applied to an annular flange on said pair of reform rollers by the end closure, said reform rollers extend outwardly toward said outer annular edge of said roller block, wherein a preferred geometric profile is created on the inner panel wall of the end closure.
[0019] It is another aspect of the present invention to provide improved end closure geometries which can be obtained utilizing the aforementioned apparatus and method and which are generally not obtainable using commonly known die presses. In one embodiment, one or more inwardly or outwardly extending reinforcing beads are formed in the chuck wall or inner or outer panel walls of the countersink to create a desired shape in a container end closure. More specifically, a metallic end closure adapted for interconnection to a sidewall of a container body is provided, comprising:
[0020] a peripheral cover hook;
[0021] a chuck wall extending downwardly from said peripheral cover hook;
[0022] a countersink comprising an outer panel wall interconnected to a lower end of said chuck wall and an inner panel interconnected to a central panel; and
[0023] a channel with a predetermined geometric profile positioned in at least one of said inner panel or said outer panel of said countersink, wherein the distance between said inner panel wall and outer panel wall at said channel is less than the distance between the outer panel wall and the lower panel wall in a lower portion of the countersink.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a front cross-sectional elevation view of one embodiment of the invention shown before reforming or spin-forming;
[0025] FIG. 2 is a front cross-sectional elevation view of the embodiment shown in FIG. 1 and showing inside reforming wherein a channel is positioned on an inner panel wall;
[0026] FIG. 2A is a front cross-sectional elevation view showing a variation of the reforming shown in FIG. 2 ;
[0027] FIG. 3 is a cross-sectional front elevation view of an alternative embodiment of the present invention, wherein an outer panel wall is reformed;
[0028] FIG. 3A is a cross-sectional front elevation view depicting a variation of the embodiment shown in FIG. 3 ;
[0029] FIG. 4 is a cross-sectional front elevation view showing a shell end closure which has been reformed on both an inside panel wall and outside panel wall;
[0030] FIG. 5 is a front perspective view of one embodiment of the present invention showing the inner panel wall reformed;
[0031] FIG. 6 is a front perspective view of an alternative embodiment of the present invention showing an outer panel wall reformed;
[0032] FIG. 7 is a front perspective view of an alternative embodiment of the present invention wherein both the inner panel wall and outer panel wall have been reformed;
[0033] FIG. 8 is a front cross-sectional elevation view showing a container end closure after both the inner panel wall and outer panel wall have been reformed and further depicting a reforming assembly;
[0034] FIG. 9 is a cross-sectional front elevation view further showing the components of one embodiment of a reforming tool prior to positioning a channel in an inner panel wall of an end closure;
[0035] FIG. 10 is a cross-sectional front elevation view showing a container end closure positioned opposite a reforming tool and just prior to reforming;
[0036] FIG. 10A is a front cross-sectional view of the embodiment shown in FIG. 10A and after a reforming channel has been positioned in an inner panel wall;
[0037] FIG. 11 is a top front perspective view of a container end closure positioned on top of a spin-forming assembly and depicting the reprofile rollers in operable contact with an outer panel wall of a container end closure; and
[0038] FIG. 12 is an alternative embodiment of the spin-forming assembly of FIG. 11 , and depicting two interior reform rollers and four reprofile rollers.
[0039] For clarity, the following is a list of components generally shown in the drawings:
[0000]
No.
Components
2
End closure
4
Central panel
6
Peripheral cover hook
8
Chuck wall
10
Countersink
12
Countersink inner panel wall
14
Countersink outer panel wall
16
Channel
18
Container
20
Container neck
22
Double seam
24
Panel radius
26
Inside reform radius
28
Outside reform radius
30
Reform gap
32
Spin forming assembly
34
Roller block
36
Reform Rollers
38
Roller block leading surface
40
Roller block central aperture
42
Mounting shaft
44
Reprofile rollers
DETAILED DESCRIPTION
[0040] Referring now to FIGS. 1 through 11 , various embodiments of the present invention are provided herein. More specifically, FIG. 1 depicts a typical beverage container end closure shell shown before a reforming or “spin-forming” procedure has been performed. More specifically, the end closure 2 is generally comprised of a peripheral cover hook 6 , a chuck wall 8 which extends from the peripheral cover hook 6 and which is interconnected to a countersink 10 on a lower end. The countersink 10 is generally comprised of an inner panel wall 12 and an outer panel wall 14 , and wherein the inner panel wall 12 is interconnected to the central panel 4 .
[0041] Referring now to FIG. 2 , the end closure of FIG. 1 is shown after an inner panel wall reforming or spin-forming procedure has been performed. More specifically, after the positioning of the inside reforming tool, a channel 16 is formed in the inner panel wall of the countersink, thus changing the geometric profile and in this particular embodiment providing a channel radius of approximately 0.035 inches. As appreciated by one skilled in the art, the actual geometric configuration and/or size of the channel 16 is not critical to the present invention, but rather the novelty in one embodiment relates to the method of forming the channel 16 in the various geometries which can be obtained using this method which are impractical or impossible to perform in a typical die press. Based on these novel methods and the apparatus used for form these geometries, unique and novel end closure geometries can be formed which are not possible with typical die presses. In one embodiment, it is anticipated that the channel on either the inner panel wall 12 or outer panel wall 14 may have a radius of between about 0.005-0.035 inches. Referring now to FIG. 2A , a slight variation of the geometry shown in FIG. 2 is provided herein, and wherein the inner panel wall has a distinct shape positioned near a lowermost portion of the countersink, and which is entirely different than the embodiment shown in FIG. 2 .
[0042] Referring now to FIGS. 3 and 3A , an alternative embodiment of the present invention is provided herein, wherein the channel 16 is positioned on an outer panel wall of the countersink 10 . FIG. 3A represents a variation of the embodiment shown in FIG. 3 , wherein the geometry is distinct and the channel 16 is not as pronounced as the embodiment shown in FIG. 3 , and is positioned on a lower portion of the outer panel wall 16 . As further shown in FIG. 3 , depending on the depth of the channel 16 , a reform gap 30 is created and which may have a dimension of between about 0.070-0.005 inches. Alternatively, the reform gap 30 may be eliminated altogether by creating a deep channel 16 .
[0043] Referring now to FIG. 4 , an alternative embodiment of the present invention is provided herein, wherein both the inner panel wall 12 and outer panel wall 14 of the end closure 2 have been reformed to create a channel 16 which substantially oppose each other. Although in this embodiment a reform gap 30 is provided, as mentioned above, the channel on the inner panel wall and/or an outer panel wall may be deep enough to completely eliminate the gap 30 , and wherein the inner panel wall and outer panel are in contact with each other. In either embodiment, the diameter between the channels 16 is less than the diameter between the lowermost portion of the inner panel wall 12 and outer panel wall 14 .
[0044] Referring now to FIGS. 5-7 , front perspective views of alternative embodiments of the present invention are provided herein. More specifically, FIG. 5 is an embodiment showing an end closure 2 having a channel 16 positioned on the inner panel wall, while FIG. 6 is a front cut-away perspective view showing the channel 16 positioned on the outer panel wall of the countersink 10 . Alternatively, FIG. 7 is a cross-sectional front perspective view showing a channel 16 positioned on both the inner panel wall and the outer panel wall of the countersink 10 .
[0045] Referring now to FIG. 8 , a cross-sectional front elevation view is provided which further depicts one embodiment of a dual reforming or spin-forming assembly 32 used to shape the end closure 2 to a desired geometric profile. As provided herein, the term “reform” or “spin-forming” may describe changing the geometric profile of the inner panel wall and/or outer panel wall or both, or the term “reprofiling” may additionally be used to describe the same process. In the drawing shown in FIG. 8 , reform rollers 36 are shown after engagement with the inner panel wall of the countersink, while reprofile rollers 44 are shown just after engagement with the outer panel wall of the end closure 2 to create a preferred geometric shape 42 . In one embodiment, the reform rollers and reprofile rollers 44 are interconnected to a mounting shaft 42 and roller block assembly 32 which is used to support and spin the roller block end or reprofile rollers 44 .
[0046] Referring now to FIG. 9 , an alternative embodiment of the present invention is shown wherein a roller block reforming and reprofiling assembly 32 is shown in an opposing position to an end closure 2 , and just prior to preparing a channel 16 in the inner panel wall of the countersink. As previously mentioned, depending on the geometric profile of the reform rollers 36 , the geometry and depth of the channel 16 can be any size and dimension depending on the performance criteria of the end closure 2 .
[0047] Referring now to FIGS. 10 and 10A , cross-sectional front elevation views are provided which show additional detail of the reform rollers 36 just prior to reforming in FIG. 10 and after reforming in FIG. 10A . As shown, after the reform roller 36 is placed in contact with the inner panel wall of the end closure 2 , a channel 16 is created between the central panel 4 and the countersink 10 . The end closure 2 is generally held stationary while the reform rollers 36 spin, although alternatively the reform rollers 36 can be held stationary while the end closure 2 is spun around an axis which is substantially parallel to the drive shaft of the reform assembly or perpendicular to the drive shaft assembly.
[0048] Referring now to FIG. 1 , a front perspective view of one embodiment of the present invention is provided herein and which more clearly shows a roller block 34 , a roller block leading surface 38 , and the reprofile rollers 44 positioned in opposing relationship to the end closure 2 . Although FIG. 11 depicts two reprofile rollers 44 interconnected to the roller block 34 , as appreciated by one skilled in the art, as few as one and as many as four or five reform rollers and/or reprofile or spin-form rollers can be used to provide a preferred geometry in a container end closure.
[0049] FIG. 12 depicts an alternative embodiment of a spin-rolling apparatus 32 , and which is shown without an end closure engaged thereto. As generally shown, the spin-forming apparatus in this embodiment includes two reform rollers 36 which are designed to move outwardly, and four reprofile rollers 44 which are generally designed to engage an outer panel wall of an end closure during a spin-forming operation.
[0050] While an effort has been made to describe various alternatives to the preferred embodiment, other alternatives will readily come to mind to those skilled in the art. Therefore, it should be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. Present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not intended to be limited to the details given herein.
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A metallic container end closure is provided which includes a channel or groove in a predetermined location in at least one of an inner panel wall, outer panel wall, or chuckwall, and which is formed by a shaping tool. An apparatus and method for spin-forming the end closure with the improved geometry is also provided herein.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a 371 of PCT/EP2012/068592, filed Sep. 21, 2012, which claims the benefit of U.S. Provisional Patent Application No. 61/538,265, filed Sep. 23, 2011, the contents of each of which are incorporated herein by reference.
FIELD OF THE INVENTION
The present invention relates to chemical compositions and methods for the rapid and sustained prevention, control, and removal of sulfhydryl compounds, such as hydrogen sulfide, and its corresponding corrosion products from industrial process streams. It further relates to the use of chemical compositions and methods for reducing both the oxidant demand by sulfhydryl compounds in industrial process streams as well as the corrosion rates in said systems.
BACKGROUND OF THE INVENTION
The prevention, removal, and remediation of hydrogen sulfide (H 2 S) and other sulfhydryl compounds from liquid or gaseous industrial process streams is a challenge in a wide range of industries. The presence of H 2 S poses significant environmental and safety concerns to personnel and operators. This is due in part to the fact that H 2 S is highly flammable, highly toxic when inhaled (8 h of exposure at 100 ppm has been reported to cause death while levels of 1,000 ppm can cause death within minutes), highly corrosive, and malodorous. Further, corrosion and scale deposits resulting from the presence of hydrogen sulfide in contact with metallic surfaces, such as carbon steel pipes can further disruption industrial operations via the plugging of pipes, valves, nozzles, and the like.
In the oil and gas industry, the removal of H 2 S is important for the transport and storage of crude reserves as well as meeting standards for downstream refining, an important consideration due to sulfide poisoning of cracking catalysts and transmission of gas. Further, in both the refining industry and geothermal power industry, cooling tower process water can contain moderate to high levels of H 2 S, both causing significant solids development as well as increasing the level of oxidant demand so as to make oxidants unviable options for microbial control in these systems.
Nonetheless, the challenge of removing and/or reducing H 2 S from process streams has been addressed with a variety of different technologies. Common techniques utilize either absorption with a solvent or solid phase material with subsequent regeneration of the absorbent, or reaction with a suitable substance or substrate that produces a corresponding reaction product. This reactivity has often involved the reaction of H 2 S with various types of aldehydes. For instance, U.S. Pat. No. 1,991,765 was an early example describing the reaction of formaldehyde with hydrogen sulfide to form an insoluble product, later identified as the sulfur heterocycle 1,3,5-trithiane.
U.S. Pat. No. 2,426,318 discloses a method of inhibiting the corrosivity of natural gas and oil containing soluble sulfides by utilizing an aldehyde such as formaldehyde.
U.S. Pat. No. 3,459,852 discloses a method for removing sulfide compounds with α,β-unsaturated aldehydes or ketones such as acrolein or 3-buten-2-one as the reactive compounds. Nonetheless, acrolein is a hazardous, highly toxic chemical limiting extensive use in a wider variety of applications.
U.S. Pat. No. 4,680,127 describes a method for reducing H 2 S in a neutral to alkaline aqueous medium (pH ˜7-9) with the formation of solids, a problem when using formaldehyde, using glyoxal and glyoxal/formaldehyde mixtures without the formation of solids. However, the glyoxal/formaldehyde mixtures exhibited slower rates of H 2 S scavenging than glyoxal alone.
European patent application EP 1 624 089 A1 describes the use of mixtures of glyoxal with a metal nitrate compound in conjunction with triazines or N-chlorosuccinimide for preventing H 2 S odor generation, particularly that being microbial in origin, but not being biocidal. This reduction in H 2 S was reported to reduce corrosion as well. The use of the N-chlorosuccinimide was for the purpose of maintaining a particular redox potential and intended to oxidize or consume residual H 2 S. Maintenance of a halogen residual after H 2 S scavenging is not described.
U.S. Pat. No. 4,978,512 describes a method whereby an alkanolamine and an aldehyde are combined to form a triazine in order to scavenge H 2 S.
U.S. Pat. No. 5,498,707 describes a composition wherein a diamine and an aldehyde donor are utilized to scavenge H 2 S from liquid or gaseous process streams.
The composition forms water soluble polymers but does not claim to impact iron sulfide scale.
U.S. Pat. No. 7,438,877 discloses a method for H 2 S removal utilizing mixed triazine derivatives for improved scavenging. The mixture improves the overall scavenging capacity of triazines, but whether complete removal is achieved for a theoretically stoichiometric amount is not reported. However, it is known that typically triazines, such as hydroxyethyl triazines, do not scavenge H 2 S stoichiometrically (i.e., 3 mol of H 2 S per mol triazine) due to formation of cyclic thiazines that do not further react with H 2 S (Buhaug, J.; Bakke, J. M. “Chemical Investigations of Hydroxyethyl-triazine and Potential New Scavengers”, AIChE 2002 Spring National Meeting).
In addition, methods and compositions have been described for the treatment of iron sulfide deposits. For instance, U.S. Pat. No. 6,986,358 discloses a method for combining an amine with tris(hydroxymethyl)phosphine in a reaction at a pH of 8 to complex and dissolve deposits of iron sulfide. Similarly, the combination of ammonia with bis-(tetrakis(hydroxymethyl)phosphonium) sulfate forms a tetradentate ligand that complexes iron (Jeffrey, J. C.; Odell, B.; Stevens, N.; Talbot, R. E. “Self Assembly of a Novel Water Soluble Iron(II) Macrocyclic Phosphine Complex from Tetrakis(hydroxymethyl)phosphonium Sulfate and Iron(II) Ammonium Sulfate”: Chem. Commun., 2000, 101-102. Further, WO 02/08127 A1 combines the concept of using an amine, carboxylic acid amine salt, aminophosphonic acid, or ammonia in combination with bis-(tetrakis(hydroxymethyl)phosphonium) sulfate or tris(hydroxymethyl)phosphine to inhibit and reduce the amount of iron sulfide deposits in a water system.
While multiple methods have been developed for scavenging H 2 S and sulfhydryl compounds from industrial process systems, a high capacity, fast reacting method for reducing hydrogen sulfide, mitigating sources of hydrogen sulfide, such as microbiological sources, and removing products of hydrogen sulfide corrosion, such as iron sulfide, which performs at similar levels over a wide pH range and does reduces solids formation is still desired. Further, it is desirable to be able to use the chemical in industrial process systems that have H 2 S present via either process leaks or influent, such as produced water storage tanks, fracturing fluids, cooling tower refineries, and geothermal cooling towers.
SUMMARY OF THE INVENTION
In order to address the need to prevent, inhibit, and remediate H 2 S and its scale deposits from multiple sources, the present invention provides a composition obtained by combining at least one aldehyde or aldehyde donor that is not a triazine with the reaction product of an amino acid and a hydroxymethylphosphine or hydroxymethylphosphonium salt and, optionally, a quaternary ammonium salt or amine. Preferably, the pH of the composition is adjusted between about 1 and about 9, more preferably between about 2 and about 7, and most preferably between about 3 and about 6.
Another aspect of the present invention is a method of preventing the formation of and reducing the amount of iron sulfide in an industrial water or process circuit, such as an oil and gas pipeline or geothermal cooling tower. The inventive method comprises adding the composition described above to inhibit, disperse, and dissolve iron sulfide deposits within an industrial process circuit.
Another aspect of the present invention is a method of preventing the formation of hydrogen sulfide and, consequently, iron sulfide in an industrial water or process circuit due to microbial contamination. The inventive method comprises adding the composition described above to inhibit or reduce the growth of sulfate-reducing bacteria.
In one embodiment of the invention, the at least one aldehyde or formaldehyde releasing compound is selected from the group consisting of hydroxymethylhydantoins, bis(hydroxymethyl)hydantoins, imidazolidinyl urea, glyoxal, formaldehyde, glutaraldehyde, and acrolein.
In one embodiment of the invention, the amino acid is combined with the hydroxymethylphosphine or hydroxymethylphosphonium compound at acidic pH prior to combination with the aldehyde or aldehyde donor.
The hydroxymethylhydantoins are preferably selected from the group consisting of 1-hydroxymethyl-5,5-dimethylhydantoin, 3-hydroxymethyl-5,5-dimethylhydantoin, 1,3-bis(hydroxymethyl)-5,5-dimethylhydantoin, and mixtures thereof.
The amino acids may be α-amino acids or other amino acids such as β- or ω-amino acids. With the exception of glycine, α-amino acids can exist in two or more stereoisomeric forms, namely the L -form (which is the form usually found in proteins) and the D -form. For the purpose of this invention all stereoisomers as well as their (racemic or non-racemic) mixtures are suitable and here and in the following the plain names of the amino acids are meant to comprise all stereoisomers as well as their mixtures. Particularly useful amino acids are those selected from the group from the group consisting of glycine, lysine, alanine, histidine, aspartic acid, glutamic acid, serine, threonine, asparagine, glutamine, cysteine, proline, valine, isoleucine, leucine, methionine, phenylalanine, tyrosine, tryptophan, and 12-aminolauric acid.
In another embodiment of the composition of the present invention, a quaternary ammonium compound or amine can be combined with the amino acid and hydroxymethyl phosphine or phosphonium salt reaction product and aldehyde or aldehyde donor wherein the quaternary ammonium compound has a formula of (R 1 R 2 R 3 R 4 N + ) n X n− wherein R 1 , R 2 , R 3 , and R 4 are each independently an alkyl group having from 1 to 30 carbon atoms or an arylalkyl group having from 7 to 30 carbon atoms, and X n− s a mono- or polyvalent anion such as a halide, a C 2-20 mono- or dicarboxylate, a borate, nitrate, bicarbonate, carbonate, sulfamate, a sulfonate, sulfate, or a phosphate.
Alkyl groups are any linear, branched or cyclic saturated hydrocarbyl groups having the stated number of carbon atoms. Arylalkyl groups are alkyl groups substituted with an aryl group, preferably with a phenyl group, such as benzyl (phenylmethyl) or phenylethyl.
Halides are fluorides, chlorides, bromides or iodides, preferably chlorides or bromides.
C 2-20 mono- or dicarboxylates are anions derived from saturated or unsaturated mono- or dicarboxylic acids having 2 to 20 carbon atoms, such as acetate, propionate, butyrate, pentanoate, hexanoate, octanoate, decanoate, dodecanoate (laurate), tetradecanoate (myristate), hexadecanoate (palmitate), octadecanoate (stearate), oleate, linolate, oxalate, malonate, succinate, glutarate, adipate, 1,8-octanedioate, 1,10-decanedioate, 1,12-dodecanedioate and the like.
Borates may be monoborates (containing the BO 3 3− anion) or polyborates such as di-, tri-, tetra-, penta-, hexa-, or octaborates.
Sulfonates may be alkanesulfonates, such as methanesulfonate or trifluoromethanesulfonate, or arenesulfonates, such as benzene- or toluenesulfonate.
Sulfates may be “neutral” sulfates or “acid” sulfates (hydrogensulfates, bisulfates).
Similarly, phosphates may be orthophosphates (PO 4 3− ), hydrogenphosphates (HPO 4 2− ) or dihydrogenphosphates (H 2 PO 4 − ).
The substituted N-hydrogen compound is preferably selected from the group consisting of p-toluenesulfonamide, 5,5-dialkylhydantoins, methanesulfonamide, barbituric acid, 5-methyluracil, imidazoline, pyrrolidone, morpholine, ethanolamine, acetanilide, acetamide, N-ethylacetamide, phthalimide, benzamide, succinimide, N-methylurea, acetylurea, methyl allophanate, methyl carbamate, phthalohydrazide, pyrrole, indole, formamide, N-methylformamide, dicyanodiamide, ethyl carbamate, 1,3-dimethylbiuret, methylphenylbiuret, 4,4-dimethyl-2-oxazolidinone, 6-methyluracil, 2-imidazolidinone, ethyleneurea, 2-pyrimidone, azetidin-2-one, 2-pyrrolidone, caprolactam, phenylsulfinimide, phenylsulfinimidylamide, diaryl- or dialkylsulfinimides, isothiazoline-1,1-dioxide, hydantoin, glycinamide, creatine, glycoluril, C 1-20 alkylamines, (C 1-20 alkyl)-alkylenediamines, or (C 1-20 alkyl)-alkylenetriamines.
The hydroxymethylphosphine or hydroxymethylphosphonium compound is preferably selected from the group consisting of tris-(hydroxymethyl)phosphine, tetrakis(hydroxymethyl)phosphonium chloride, bis-[tetrakis(hydroxymethyl)phosphonium]sulfate, 1,2-bis[bis(hydroxymethyl)phosphino]benzene, 1,ω-bis[bis(hydroxymethyl)-phosphino]alkylenes wherein the alkylene is a C 1-6 methylene chain, tris(hydroxymethyl)(C 1-20 alkyl)phosphonium halides, and tris(hydroxymethyl)(aryl-C 1-20 alkyl)-phosphonium halides.
DETAILED DESCRIPTION OF THE INVENTION
The present invention effectively inhibits the generation of and decreases the levels of hydrogen sulfide and sources of hydrogen sulfide, such as sulfate reducing bacteria, and iron sulfide deposits in industrial process systems. In contrast to previously disclosed methods, such as that described in U.S. Pat. No. 6,986,358, the present invention can be performed effectively at both acidic and basic pH when the composition is contacted with the industrial process stream.
The compositions of this invention are obtained by initially generating the reaction product of an amino acid and a hydroxymethylphosphine or hydroxymethylphosphonium salt at acid pH via the direct combination of the amino acid with the hydroxymethylphosphine or hydroxymethylphosphonium salt at a molar ratio amino acid/hydroxymethyl phosphine of 1:1 to 12:1. Although such products have been previously described for biomedical motifs in the reaction with amino acids and peptides (Berning, D. E.; Katti, K. V.; Barnes, C. L.; Volkert, W. A. “Chemical and Biomedical Motifs of the Reactions of Hydroxymethylphosphines with Amines, Amino Acids, and Model Peptides”, J. Am. Chem. Soc., 1999, 121, 1658-1664), the efficiency of such reaction products in dissolving iron sulfide has not been previously reported. Surprisingly, it has been found that combinations of these reaction products with hydrogen sulfide scavengers and, optionally, quaternary ammonium compounds or amines result in more rapid iron sulfide dissolution than previously disclosed compositions (U.S. Pat. No. 6,986,358), as well as rapidly prevent the formation of residual iron sulfide scale within a system. A particularly useful aspect of the present invention is the avoidance of polymeric precipitates upon mixing the amino acid and the hydroxymethylphosphine or hydroxymethylphosphonium salt, as observed with ammonia and its salts (U.S. Pat. No. 6,986,358).
The amino acid and hydroxymethylphosphine or hydroxymethylphosphonium salt reaction product is then combined with either an aldehyde or aldehyde donor, such as a methylolhydantoin, and optionally combined with a quaternary ammonium compound or amine. The preferred pH of the composition is adjusted between about 1 and about 9, more preferably between about 2 and about 7, and most preferably between about 3 and about 6 with an appropriate acid or base, such as hydrochloric acid or sodium hydroxide, if necessary.
Quaternary ammonium compound of the general formula of (R 1 R 2 R 3 R 4 N + ) n X n− , wherein R 1 , R 2 , R 3 , and R 4 are each independently an alkyl or arylalkyl group having from 1 to 30 carbon atoms and X n− is a mono- or polyvalent anion such as a halide, a C 2-20 mono- or dicarboxylate, a borate, nitrate, bicarbonate, carbonate, sulfamate, a sulfonate, sulfate, or a phosphate are particularly efficacious. Examples include didecyldimethylammonium chloride, didecyldimethylammonium carbonate, didecyldimethylammonium phosphate, didecyldimethylammonium sulfamate, didecyldimethylammonium citrate, (C 10-18 alkyl)-dimethyl-benzylammonium chloride, or (C 10-18 alkyl)-dimethyl-benzylammonium carbonate. Commercially available products include Bardac™ 2280, Carboquat™ 250 WT, Barquat™ MB-80, and Barquat™ 50-28, all available from Lonza Inc, Allendale, N.J.
The compositions used in the method of the present invention are particularly suitable for scavenging H 2 S and preventing iron sulfide deposition. Molar ratios of the composition to the amount of H 2 S present in the system are preferably from 0.25:1 to 100:1, more preferably from 1:1 to 60:1, most preferably from 4:1 to 30:1 of the aldehyde or aldehyde donor, preferably from 0.25:1 to 50:1, more preferably from 1:1 to 30:1, most preferably from 2:1 to 10:1, for the reaction product of an amino acid with the hydroxymethyl phosphonium salt, and preferably from 0.25:1 to 100:1, more preferably from 1:1 to 60:1, most preferably from 4:1 to 30:1 of the quaternary ammonium or N-Hydrogen compound, or mixture thereof. Further, these compositions may optionally comprise additional additives such as surfactants, dispersants, demulsifiers, scale inhibitors, corrosion inhibitors, anti-foaming agents, oxygen scavengers such as ascorbic or erythorbic acid, and flocculants.
In a preferred application of the method of the present invention the industrial process system is selected from the group consisting of an oil and gas production system, a produced water storage tank, an oil storage tank, an oil or gas transmission pipeline, ballast water tank, or oil transportation tank.
In another preferred application of the method of the present invention the industrial process system is a cooling tower such as a refinery or geothermal cooling tower.
In still another preferred application of the method of the present invention the industrial process system is a fuel storage tank.
In still another preferred application of the method of the present invention the industrial process system is an oil storage tank or transport system.
In still another preferred application of the method of the present invention the industrial process fluid is a fracturing fluid or a drilling mud.
In a preferred embodiment of the method of the present invention the aldehyde or aldehyde donor, the reaction product of the hydroxymethylphosphine or hydroxymethylphosphonium compound and amino acid, and, optionally, the quaternary ammonium compound or N-hydrogen compound, are combined prior to addition to the system.
In another preferred embodiment of the method of the present invention the aldehyde or aldehyde donor and the reaction product of the hydroxymethylphosphine or hydroxymethylphosphonium compound and amino acid are combined prior to addition to the system and the quaternary ammonium compound or N-hydrogen compound is added separately to the system.
In still another preferred embodiment of the method of the present invention the aldehyde or aldehyde donor and the quaternary ammonium compound or N-hydrogen compound are combined separately from the reaction product of the hydroxymethylphosphine or hydroxymethylphosphonium compound and amino acid and each combined product is added separately to the system.
The following examples are given to illustrate the present invention. It should be understood, however, that the invention is not intended to be limited to the specified conditions or details described in the examples.
Example 1
In order to demonstrate the H 2 S scavenging ability of products of the present invention, 400 g of a model process water system at 400 ppm alkalinity was deoxygenated with a stoichiometric amount of oxygen scavenger (ammonium bisulfite) and the pH adjusted with either HCl, NaOH, or CO 2 . Water (400.0 g) was charged with a NaSH standard in order to achieve a H 2 S concentration of about 50 ppm, followed by a solution containing 2.00 g of a 70% solution of 1,3-dimethylol-5,5-dimethylhydantoin. A solution of a composition according to the present invention was prepared by combining glycine (0.11 mol) with bis[(tetrakishydroxymethyl)phosphonium]sulfate (0.018 mol) and water (0.92 mol). 5.02 g of the resulting solution was combined with an equivalent weight of 70% (w/w) solution of methylolhydantoin and dosed such that the corresponding hydrogen sulfide solution contained the corresponding amount of methylolhydantoin scavenger. Reaction progress was monitored by measuring the residual H 2 S at specified time intervals via titration.
The % residual H 2 S levels are shown as a function of pH versus other known chemical technologies. The high performance capacity and pH-insensitive performance of the products of the present invention are readily observed.
TABLE 1
pH
Time (min)
5
7.2
8.4
9.4
0
100%
100%
100%
100%
2.5
86%
90%
88%
91%
5
86%
89%
88%
94%
15
71%
77%
77%
81%
60
46%
50%
38%
35%
90
25%
32%
27%
34%
125
—
—
13%
—
150
19%
14%
—
—
180
—
11%
—
11%
Example 2
In order to demonstrate the H 2 S scavenging ability of products of the present invention, 400 g of a model process water system at 400 ppm alkalinity was deoxygenated with a stoichiometric amount of oxygen scavenger and adjusted with either NaOH or CO 2 to a pH of 9.4. The water was charged with a NaSH standard to achieve ˜50 ppm H 2 S, followed by a scavenger solution containing 2.00 g of a 70% solution containing 1,3-dimethylol-5,5-dimethylhydantoin, prepared as described in Example 1 (molar ratio of scavenger to H 2 S:14:1). For comparison, triazine H 2 S scavenging was also evaluated under similar conditions at equivalent levels. Reaction progress was monitored by measuring the residual H 2 S at specified time intervals via titration. The higher performance capacity products of the present invention are readily observed.
TABLE 2
Present
Time (min)
Invention
Triazine
0
100%
100%
2.5
91%
91%
5
94%
89%
15
81%
98%
30
61%
97%
60
35%
—
90
34%
—
125
—
83%
180
11%
—
Example 3
In order to demonstrate the superior iron sulfide dissolution ability of the products of the present invention, the time to complete dissolution of iron sulfide was compared. To a 10 mL vial containing an iron filing in 1% NaCl, an HCl and NaSH standard solution was added to generate 480 ppm H 2 S at pH ˜5. Immediate formation of iron sulfide was observed. The precipitate was treated with the reaction product of 0.11 mol glycine with 0.018 mmol bis-[tetrakis(hydroxymethyl)phosphonium]sulfate (6:1 molar ratio) in 0.92 mol of water, prepared in a manner analogous to that described in Berning, D. E.; Katti, K. V.; Barnes, C. L.; Volkert, W. A. “Chemical and Biomedical Motifs of the Reactions of Hydroxymethylphosphines with Amines, Amino Acids, and Model Peptides”, J. Am. Chem. Soc., 1999, 121, 1658-1664. 5.02 g of this solution was combined with 5.05 g of a 70% solution containing 1,3-dimethylol-5,5-dimethylhydantoin. For comparison, the rate of iron sulfide dissolution of the reaction of ammonia with bis-[tetrakis(hydroxymethyl)phosphonium]sulfate was compared.
TABLE 3
Time to Complete Dissolution
Present Invention
NH 3 + THPS
(10% as product)
(10% as Product)
7.0 min
17.5 min
Example 4
In order to demonstrate the prevention of generation of iron sulfide deposits via chemical sources by compositions of the present invention, 1.0 mL multiple concentrations of the product as prepared in Example 3 were added to 9 mL of 1% salinity water in oxygen-free vials containing iron filings for iron sulfide generation upon addition of a sulfide source (target 500 ppm as H 2 S). As shown in Table 4, iron sulfide was generated immediately in the control sample upon addition of sulfide, whereas complete scavenging of H 2 S and rapid dissolution of iron sulfide was observed at multiple concentrations of formulations of the present invention.
TABLE 4
Formulation Concentration
Observation
10%
4%
2%
1%
0.85%
0%
FeS formed
No
No
No
No
Yes
Yes
upon H 2 S
addition?
Reduced
Yes
Yes
Yes
Yes
Yes
—
FeS relative
to Control?
Solution
Clear
Clear
Clear
Clear
Gray/
Black
after 1 min
Black
Solution
Clear
Clear
Clear
Clear
Slight
Black
after 8 min
Gray
Haze
Example 5
In order to demonstrate the ability of compositions of the present invention to prevent FeS formation, a solution was prepared via combination of 0.11 mol of glycine with 0.018 mol of bis((tetrakishydroxymethyl)phosphonium) sulfate and 0.92 mol of water. 3.77 g of this solution was combined with 3.78 g of a solution containing methylolhydantoin (mixture containing 1,3-dimethylol-5,5-dimethylhydantoin and monomethylol-5,5-dimethylhydantoins) and 2.54 g of a 70% solution of dimethyldidecylammonium chloride. 1 mL of the resulting solution was added to 9 mL of a 1% brine solution containing an iron nail. 0.15 mL of 1 N HCl was added, followed by 0.20 mL of a 39,500 ppm NaSH solution and compared to a control sample without the solution. No FeS was formed in the solution containing 1% of a mixture of the present invention, whereas FeS was formed in the control.
|
The invention relates to a method for the prevention and removal of H 2 S and/or other sulfhydryl compounds and iron sulfide deposits from gas and/or liquid streams in industrial process systems. Formulations comprising aldehydes, aldehyde donors, and/or aldehyde stabilizers, excluding triazines, in combination with the reaction product of an amino acid and a hydroxymethylphosphine or hydroxymethylphos-phonium salt, and optionally a quaternary ammonium compound and/or one or more N-hydrogen compounds such as 5,5-dialkylhydantoin or amines, are rapidly and sustainedly scavenging H 2 S originating from process and/or microbial sources. The formulations possess high capacities for H 2 S removal and are relatively pH-insensitive.
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FIELD OF THE INVENTION
[0001] The present invention relates to the field of portable electronic devices and networked electronic communication.
BACKGROUND OF THE INVENTION
[0002] In using any kind of networked communication device, each user has a user profile that defines a personalized electronic environment for that particular communication device.
[0003] For example, while surfing the Internet on a personal computer, each Web site supplies individual browsers with unique cookies that store identifying information in the user's Internet browser. When visiting specific web sites, the cookies stored in the browser identify each individual to the web site. Based on the information stored in the browser's cookies, each Web site personalizes its contents according to the individual Internet browser. An individual may select bookmarks or favorite Web sites, which are stored on the individual's personal computer persistent memory (hard drive) and which further customize the electronic environment to suit the user.
[0004] As another example of a personalized identity in a networked electronic environment, in a cable television (CATV) system, each subscriber or household subscribes to different programming. Some subscribers have basic cable, while other subscribers have basic cable plus some premium channels. Each member of the household generally has different favorite channels. Additionally, some cable households have broadband Internet access via CATV using a cable modem. In such case, the CATV settop, in communication with a computer at the CATV headend, acts as an Internet browser. However CATV settop boxes tend to have limited computing capabilities, and in particular, CATV settop boxes tend to have limited persistent memory in which to store personalized information such as cookies.
[0005] As another example of a personalized identity in a networked electronic environment, a wireless cellular telephone system provides different subscribers with different calling plans specifically selected by the subscriber. Some cellular telephone networks also offer Internet connectivity to their customers. However, as in the case of CATV settop boxes, cellular phones tend to have limited capabilities as Internet browsers, and in particular, tend to have limited persistent memory storage for personalized information such as cookies.
[0006] When away from the home environment, the electronic environment is different from that at home. For example, using a settop box in a hotel room means that the subscriber typically does not have access to familiar television programs or customized Internet interface. Borrowing or renting a cellular telephone means that the subscriber may not have access to his regular calling plan, is unable to receive incoming calls using his regular phone number, and does not have the customized Internet environment as he would at home. Generally, when a traveler is surfing the Internet at a remote location, whether it be a computer, a remote CATV settop or a cellular phone away from home, Web sites that normally have customized content suited to the traveler, will not recognize the individual Internet browser while at such remote communications device.
SUMMARY OF THE INVENTION
[0007] The present invention is embodied in a digital identity server operating as a node on a distributed computing network such as the Internet.
[0008] In accordance with the present invention, a user enters unique identifying information into an electronic communication device. For example, an email address is unique to each person and entering an email address uniquely identifies the individual to the electronic communication device. Furthermore, entering a password in addition to an email address authenticates the user.
[0009] In order to personalize the electronic environment, the electronic communication device forwards the user's unique identifying information to the digital identity server via the Internet. The nature and capabilities of the given remote electronic communication device is also forwarded to the digital identity server. The digital identity server responds by transmitting a digital identity corresponding to the user to the given electronic communication device. The received digital identity defines the services for which the user is authorized (e.g. in the case of a CATV subscriber, the received digital identity includes a list of the premium channels that the subscriber is authorized to view). Furthermore, the digital identity server provides a level of functionality suited to the capabilities of the particular electronic communication device. The electronic communication device receives the digital identity of the user and personalizes its operation to suit the user.
[0010] The electronic communication device that retrieves the digital identity of the user and personalizes its operation to suit the user may be a CATV settop box, a cellular telephone, a computer, a video game console, an Internet access terminal, a payphone, a vending machine or any present or future electronic communication device. In such manner, the digital identity of the user is made portable, and follows the user wherever the user may go providing the user with the same electronic environment accessible from any electronic communication device.
[0011] In addition, the portable digital identity system of the present invention facilitates the use of simplified electronic communication devices. In particular, electronic communication devices accessing the user's portable digital identity may be implemented using very thin client software and/or without persistent data storage, making the electronic communication device smaller, lighter and less expensive.
[0012] The portable digital identity includes email preferences, email address book and email client software settings, thereby presenting to the user a seamless and consistent email environment. The portable digital identity includes TV preferences, permitting the user to watch his favorite shows and have his premium channels be available from any hotel room. The portable digital identity includes preferred credit card and shipping information (work and home addresses), as well as preferred carriers and other preferences to facilitate eCommerce applications.
[0013] The portable digital identity of the present invention permits the user to access familiar services across different platforms. For example, the present invention permits cross platform authorization (e.g. TV to PC) so that the user may access HBO on a PC. That is, an HBO subscriber may not only access HBO from any remote CATV settop, but may also access HBO on a PC (to the extent that HBO is available via a broadband Internet connection).
[0014] The portable digital identity of the present invention includes demographic profiles and marketing data on user's activities and preferences across devices and in real time. In such manner, for example, an online newspaper viewed at a remote location, contains articles of interest to the subscriber and presents demographically targeted advertising tailored to the interests of the subscriber.
[0015] The portable identity of the present invention may be used to control TV appliances. For example, if a user normally records a given television show on a weekly basis, that knowledge can be used to construct a profile of the user that is then mapped to the user's portable digital identity and stored. The profile may then be used by other applications to target application content at the user the suits his or her interests.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] [0016]FIG. 1A is a block diagram of a system including a portable digital identity server and a plurality of information appliances forming a global computer network in accordance with the present invention.
[0017] [0017]FIG. 1B is a block diagram of a system embodying a portable digital identity server in accordance with the present invention.
[0018] [0018]FIG. 2A is a block diagram further detailing the system architecture of a system embodying a portable digital identity server in accordance with the present invention.
[0019] [0019]FIG. 2B is a block diagram further detailing the implementation of the data access function of a system embodied in a portable digital identity server in accordance with the present invention.
[0020] [0020]FIG. 2C is a block diagram further detailing the implementation of an other network adapter for use with a portable digital identity server in accordance with the present invention.
[0021] [0021]FIG. 3 is a block diagram of three top-level software objects: account, machine and user for use in conjunction with the present invention.
[0022] [0022]FIG. 4 is a block diagram of the attributes of an Internet browser cookie for use in conjunction with the present invention.
[0023] [0023]FIG. 5 is a block diagram of an account data object for storing an account's properties and billing information in accordance with the present invention.
[0024] [0024]FIG. 6 is a block diagram of a machine data object to representing in interactive device for use in accordance with the present invention.
[0025] [0025]FIG. 7 is a block diagram illustrating a user data object representing a user of an interactive device or application in accordance with the present invention.
[0026] [0026]FIG. 8 is a hierarchical representation of the digital identity object model embodying the present invention.
[0027] [0027]FIG. 9 is a system block diagram illustrating the scalability of the present invented system using server groups.
DETAILED DESCRIPTION
[0028] As shown in FIG. 1A, the digital identity server 100 communicates over a global computer network 114 (such as would include the Internet as part of the overall global network) with a plurality of user devices. Examples of user devices include a CATV settop 102 , a satellite receiver 104 , a cellular phone 106 , a personal digital assistant (PDA) 108 , personal computer 110 , video game console 112 or other client device 113 . Each user device connects to the Internet though another communication network. For example, a CATV settop box 102 is coupled through a CATV system, while a personal computer 110 is typically coupled through the public switched telephone network. The digital identity server 100 also communicates via the Internet 114 with a digital identity database 118 , an external database 116 as well as a command server 120 .
[0029] In operation, a user identifies himself to a user device 102 , 104 , 106 , 108 , 110 , 112 . The user device 102 , 104 , 106 , 108 , 110 , 112 requests a digital identity from the digital identity server 100 . In response, the digital identity server 100 communicates with the command server 120 to determine the nature and characteristics of the requesting user device 102 , 104 , 106 , 108 , 110 , 112 . The digital identity server 100 then retrieves the digital identity information from either the system database 118 or an external database 116 and downloads it to the requesting user device 102 , 104 , 106 , 108 , 110 , 112 . After the initial download of a digital identity to user device, the digital identity server 100 need not be involved except to download changes to update a user's digital identity.
[0030] In such manner, the digital identity server 100 mediates the user's access to applications/services and data from a variety of user devices ranging from a digital set-top box 102 to a portable personal digital assistant 108 to a mobile/cellular phone 106 to a game console 112 to a personal computer 110 .
[0031] Applications include Video-on-demand (VOD), gaming applications such as multi-player games, email, instant messaging, chat and broadcast based enhanced TV applications. In video-on demand for example, a viewer may pause a movie at a given point. The pause point of the movie becomes part of the viewer's digital identity. When the viewer returns to watch the rest of the movie, the viewer's downloaded digital identity contains the pause point. As a result, the viewer is able to continue watch the remainder of the movie at a later time from any CATV settop 102 communicating with the digital identity server 100 .
[0032] Additional applications include using an e-wallet (where the e-wallet for a user is tied to his digital identity and stored in the system) and delivering targeted advertising applications (where the profile of the user describing his interests and past behavior is tied to his digital identity and stored in the system).
[0033] The range of data contained in the portable digital identity includes the user's properties such as his preferences regarding the use of the device in question, his favorites data including the list of favorite applications and favorite Internet sites. The data includes the user's cookies which facilitate access to internet sites, and the set of applications/services that the user may access including the properties of the user for a specific application/service.
[0034] The digital identity server 100 retrieves configuration information from the command server 120 about various types or classes of devices within the system, and applies configuration information as a filter when returning digital identity data back to the user device. The set of applications and the generic user properties as well as application specific user properties are tailored take into account the processing power, network bandwidth and memory footprint capabilities of the communications device currently in use by the user. Thus, when the user is on a powerful communications device such as a personal computer 110 , the list of applications available to such user includes the full set of allowed or subscribed applications. When the user is on a less powerful device such as a set-top box 102 or a personal digital assistant 108 , the list of applications available to a user will typically include only a lesser permissible subset of applications.
[0035] The digital identity of the user remains the same regardless of the device that the user is using at any point in time. Having a consistent digital identity retrievable at any point by Internet access, allows the user to access his applications/services and data in a seamless and transparent fashion. Thus, even while “roaming” i.e. moving between multiple devices in his home, or to a device at a remote location such as a digital set-top box or game console at a friend's home, or using a cellular phone/pager in his car, the user experiences a consistent electronic environment.
[0036] Associated with the notion of a portable digital identity is the notion of a General Services Architecture. The General Services Architecture defines and describes the model that allows the use of applications/services and associated data by the user from their various devices. In particular, the General Services Architecture includes a user account that defines the applications and services to which the user subscribes.
[0037] The digital identity server 100 and a General Services Architecture allows the service provider/operator to dynamically define and add new services/applications into their server-side infrastructure. Services are available dynamically to users based on a configurable policy that can be customized to suit the business needs of the specific network operator or service provider.
[0038] Furthermore, access to the service can be controlled at a very granular level all the way down to a specific device and a specific user. User A may subscribe to the video on demand (VOD) service, but User B may not be allowed access to the service or even be allowed to subscribe to the service at all. If the user is a subscriber to a specific service he may not be able to access the VOD service unless he is on a device that is actually capable of running that service as is determined by the digital identity server dynamically.
[0039] The digital identity of the user as implemented by the digital identity server 100 includes a rich object oriented programming model that provides high reliability and high availability and scales to millions of users. The digital identity server 100 has easy extensibility to new client devices 113 and new server platforms and also provides for easy integration with existing stores 116 of user information being maintained by service providers and operators elsewhere on the Internet.
[0040] The overall digital identity system design is a four-tier architecture of clients 10 , 10 A, 12 , 12 A, adapters 18 , 14 , engine 22 with application programming interfaces 20 (APIs) and database 24 shown in FIG. 1B. The digital identity server 100 provides a mechanism to provide connectors to different devices 10 , 12 (where client software resides) that can be hooked into the internal core digital identity engine 22 . Such connectors are referred to herein as adapters 18 , 14 .
[0041] A digital identity software development kit (SDK) 16 permits other clients 12 to write specialized adapters 14 . The specialized adapter 14 is a protocol translator written by an other client 12 using the digital identity SDK 16 that uses standardized XML protocol to communicate with a standard digital identity adapter to the digital identity engine 22 .
[0042] Client software may reside in devices other than user devices 10 , 12 . In particular, a CATV system 11 B can be a CATV client. In such case, digital identity software development kit (SDK) 16 A permits a specialized adapter 14 A to be written that uses standardized XML protocol to communicate with a standard digital identity adapter to the digital identity engine 22 . As another example, a web site can be a web site client 11 A communicating with the digital identity engine 22 via a standard adapters 18 .
[0043] The digital identity engine 22 is the component that handles all access to all data that adapters 10 , 10 A, 12 , 12 A (and thus clients) is stored on the server side. The core engine 22 and its digital identity APIs 20 is written in Java to take advantage of Java Database Connectivity (JDBC) as the primary mechanism for accessing the digital identity data.
[0044] Application programming interfaces (APIs) are available as part of the TV Navigator platform (including client-side JavaScript and Java APIs) and as part of the Connect Suite platform (the server-side Java based, XML based and CORBA based APIs) that allow applications to be authored on top of the digital identity platform. CORBA, an acronym for Common Object Request Broker Architecture, is a type of object-oriented programming language system.
[0045] The digital identity server ( 100 in FIG. 1) further provides yet another interface that can be implemented by third parties in order to write specialized plug-ins ( 223 in FIG. 2A) to the digital identity server 100 . Specialized plug-ins are used to access (in a transparent manner) information residing in external systems ( 234 in FIG. 2A) and including the legacy billing and SMS systems of the CATV operator (or other service provider).
[0046] The portable digital identity server 18 , 20 , 22 of FIG. 1B is shown in further detail in FIG. 2A ( 210 ). The digital identity Engine 230 provides an application programming interface (API) 228 to client adapter writers. The digital identity API is implemented as an efficient means for adapters to name, store, and control access to user data. The design relies on a relational database to provide the storage and indexing of user data.
[0047] The digital identity engine 230 is what implements the API that adapters 222 , 224 , 226 use to perform operations on data. Adapters are software components that communicate with clients. Various adapters are developed for the various clients that digital identity server 210 supports. For example, standard adapters include a CORBA adapter, a digital television and cookie adapter 224 and an XML adapter 226 . An other adapter 212 is created using the software development kit 214 .
[0048] Various client software 202 , 203 , 204 , 206 and 208 communicates with the digital identity server 210 via a corresponding adapter. For example, provisioning application 202 and a digital identity control console 203 interface through a CORBA adapter 222 . A first generation digital television client 204 (using a proprietary protocol) interfaces through a digital television and cookie adapter 224 . A next generation digital television client communicates with the digital identity server 210 through an XML adapter 226 (using a standard version of Extensible Markup language or XML) as would an other adapter 212 . CORBA Clients use their own protocol, notably CORBA IIOP in COBRA adapter 222 , rather than XML/HTTP in adapter 226 .
[0049] Similar to the operation of FIG. 1A, the command server 238 in FIG. 2A provides data on the nature and characteristics of the requesting user device. The digital identity server 210 then retrieves the digital identity information from either the system database 236 or an external database 234 and downloads it to the requesting user device.
[0050] As shown in FIG. 2B, the digital identity engine 250 includes API implementation functions 252 responsive to the application programming interface 251 . The digital identity engine 250 further comprises a data access layer 254 responsive to the API functions 252 to perform all of the mechanisms for abstracting or accessing data out of the backend (data storage).
[0051] The API implementation 252 communicates only with the data access layer 254 and not directly with the various back-end data access functions such as Lightweight Directory Access protocol (LDAP) 258 , 268 , Java Database Connectivity (JDBC) 264 , schema mapper 266 , callout mechanism 260 and system data cache 262 . (Liberate Technologies, 2 Circle Star Way, San Carlos, Calif. 94070). The design is quite general, in the sense that adding a new mechanism for accessing data would require no changes to the API implementation functions 252 or the adapters ( 18 in FIG. 1B).
[0052] A data access layer 254 in the digital identity engine 230 provides the following functionality:
[0053] 1. Pools connections 253 to all data sources, including Group databases 272 B, System database 272 A, and Lightweight Directory Access protocol (LDAP) server(s) 268 .
[0054] 2. Dynamically updates and manage the relational database schema
[0055] 3. Use the schema mapper 256 and system data cache 262 to implement its operations and abstract from the API implementation 252 how data is accessed and where it is stored, hiding the fact that the data is distributed.
[0056] 4. Provide the implicit mapping from the schema of the objects defined in XML to the database schema
[0057] The Supported Objects are given below. These objects are the same as the objects defined in the XML Protocol as used in the digital identity server.
[0058] /account (primary object)
[0059] /user (primary object)
[0060] /machine (primary object)
[0061] /account/users (relationship—not extensible)
[0062] /account/machines (relationship—not extensible)
[0063] /machine/users (relationship—not extensible)
[0064] /user/cookies (cookies—not extensible)
[0065] /user/services (services)
[0066] /machine/services (services)
[0067] /account/services (services)
[0068] /user/favorites (collection object)
[0069] /user/addressbook (collection object)
[0070] . . . (etc)
[0071] When a new type of collection object is introduced (such as Address Book), no new API functions are needed. Only a new object, and its associated XML schema are needed. The data access layer 254 maintains objects and their mappings to physical tables automatically, so that no code has to change at the data access layer 254 when a new object is created. The same is true for new attributes of existing objects.
[0072] API Implementation
[0073] The API implementation 252 calls only the various parts of the data access layer 254 to perform the functions it needs, it does not call any other pieces, nor does it access any database ( 268 , 270 , 272 A, 272 B) directly. The data access 254 layer maps each specific digital identity API 251 call into the (more general) data access call. For example, a CreateEntity API function calls the generic “create” or “set” method in the data access layer 254 , after setting up all the right parameters, and the connection. Similarly, a GetCookies or GetProperties API function, calls a generic “get” method, after setting up all the parameters for each type of object (see object list above) to get the data from the database.
[0074] Schema Mapper 256
[0075] The Schema Mapper component 256 maintains the configuration of the XML schema objects, and their underlying physical tables. It also provides the data access layer 254 with a way to easily determine how to access a given piece of data. Furthermore, the schema mapper 256 stores XML schema blobs in the Command Server 266 , allowing the customer to extend and control the schema dynamically (through GUI tools). Finally, the schema mapper 256 stores information about where attributes reside (Database, external Lightweight Directory Access protocol (LDAP), etc).
[0076] System Data Cache 262
[0077] The system data cache 262 minimizes the need to access the System database 272 A, since it is a global bottleneck. It further stores servergroup information for users/machines/accounts in a data cache 262 so that trips to the System database 272 A are eliminated whenever possible. The system data cache 262 further provides a way for the API implementation functions 252 to efficiently discover the user/machine/account relationships. Finally, the system data cache 262 ensures that the in-memory cache is kept consistent with the database, given that there may be multiple digital identity servers 250 behind a load balancer, and the servers need to appear stateless. The function of providing consistent state conditions across multiple digital identity servers is accomplished by allowing communication between multiple digital identity servers for notification purposes when an entity is deleted or moved.
[0078] Scalability
[0079] Each digital identity server 250 has the ability to connect to any datasource in the site, including all Group databases 272 B, the System database 272 A, and all external customer data (Lightweight Directory Access protocol (LDAP) 268 , SMS 270 , etc). However, each digital identity server 250 has the notion of a home server group, namely a group database 272 B to which it is “tightly” bound, either through physical locality, or through logical locality (i.e. it expects to service a certain subset of users/machines/accounts in the normal case). The digital identity server 250 optimizes its access to its own home server group 272 B as much as possible.
[0080] The digital identity server 250 provides less optimized access to other server groups' data for administration functions (such as MoveEntity) and to external customer data. The digital identity server 250 has the option to provide access to all functions on other server groups, if the adapters/Clients do not wish to connect to another digital identity server which is non-optimized. One digital identity server is able to service several adapters simultaneously. Load Balancing (when possible) is done between the clients and the adapters. In the alternative, load balancing may be done between the adapters and the digital identity Engine through the network adapter
[0081] Call-outs to Legacy Data
[0082] The call-out component 260 retrieves data on a read-only basis from external (operator-managed) datastores 270 . The customer data retrieval typically occurs as part of an operation like getProperties in the API. Use of the call-out 260 is dictated by the Schema Mapper 256 , which notes where and how individual properties can be retrieved. The call-outs are used only for primitive properties of Entities, but may be generalized to apply to other data (like Services or Collections) as well. Data structures are discussed in conjunction with FIG. 3 through FIG. 7.
[0083] As a part of any call-out, the entityid must be converted into an ID that is meaningful for the external datastore. The conversion may involve a call into the system database 272 A or user database, to retrieve other properties. The conversion activity is performed either in the data access layer, or within the specific modules that perform the call-out.
[0084] Similarly, propertyNames needs to be converted into external attribute names; this information is generally available through the command server 266 .
[0085] When the call-out returns, the returned data is merged into the result set that is returned from digital identity (typically a sequence of PropertyNameValues), and is indistinguishable from other data.
EXTERNAL DATA—LEGACY DATASTORES
[0086] There are two call-outs shown in FIG. 2B: SMS (subscriber management system) 260 uses a general function call; Lightweight Directory Access protocol (LDAP) 258 is a special case for which higher-level support is provided. Both of these call outs are examples of the external data i.e. legacy datstores ( 234 in FIG. 2A).
[0087] SMS Call-out
[0088] The SMS callout mechanism 260 uses a function call to a customer-provided routine. Typically, the SMS module is called with an entityid and one or more propertyNames. The SMS callout resolves the Id (convert to an external id), and then makes a function call to the external routine. In a Java implementation, this routine is typically provided as a .jar file, loaded as a plugin. The argument list for external function includes at least external entity ID and propertyName(s).
[0089] Lightweight Directory Access Protocol (LDAP) Call-out
[0090] The Lightweight Directory Access protocol (LDAP) call-out provides high-level support for retrieving data from a Lightweight Directory Access protocol (LDAP) repository.
[0091] The data access layer calls the Lightweight Directory Access protocol (LDAP) module, supplying information such as the entityid and propertyName(s). The Lightweight Directory Access protocol (LDAP) call-out converts the entityId into an Lightweight Directory Access protocol (LDAP) Distinguished Name (possibly using information from the System DB or User DB), and converts the propertyNames into Lightweight Directory Access protocol (LDAP) attribute names (possibly using configuration parameters).
[0092] Using configuration parameters, it then forms and executes a complete Lightweight Directory Access protocol (LDAP) call to retrieve the data, such as an Lightweight Directory Access protocol (LDAP) URL, and processes the result set.
[0093] In a Java implementation, this Lightweight Directory Access protocol (LDAP) client can be implemented on Java Naming Directory Interface (JNDI). Most call-outs use the DirContext.getAttributes() method, to retrieve a set of Lightweight Directory Access protocol (LDAP) attribute values, which are merged into the digital identity result set.
[0094] Besides being easier to use than the more general call-out mechanism, the Lightweight Directory Access protocol (LDAP) module enables the data access layer 254 to pool 253 Lightweight Directory Access protocol (LDAP) connections, as it also does for Java Database Connectivity (JDBC) connections.
[0095] Digital Identity Software Development Kit
[0096] The diagram in FIG. 2C shows the sub-components of the Software Development Kit (SDK) and network adapter 288 . The Software Development Kit (SDK) 276 and network adapters 288 both convert between the digital identity API and the network protocol (XML/HTTP).
[0097] The SDKs implement the digital identity API, hiding implementation details behind a standard interface. SDKs are delivered as libraries, which are used by customers who build out-of-process (external) adapters.
[0098] SDKs must be written in the same language as the corresponding adapters, so separate SDKs are required for each language in which adapters are written. SDKs are required for both Java and C/C++. Java adapters may be able to run natively (in-process), if their client-server protocol allows it. In-process adapters do not require SDKs.
[0099] The primary function of the SDK is to convert digital identity API calls into network-based communication with the digital identity server. A simplified process description is:
[0100] 1. Call XML Publisher 284 to convert API command and data into XML.
[0101] 2. Call HTTP module 280 to establish communication with server through connection pool 282 ; send XML request; receive response.
[0102] 3. Call XML Parser 286 to parse response; convert to API data structures; return to caller.
[0103] Digital Identity Network Adapter 288
[0104] The network adapter 288 runs in the same process as the digital identity server, and services out-of-process adapters. The job of the network adapter 288 is the complement of the SDK 276 ; it converts XML/HTTP requests back into digital identity to API function calls. In this sense, the digital identity server is using its native network protocol as a sort of RPC mechanism for the external adapters to make calls to the digital identity engine. The extensible markup language (XML) is actually very well suited for this purpose.
[0105] Similar conversions to/from XML (shown as XML Publisher 284 and XML Parser 286 ) are performed in both the SDK and network adapter. These conversions share the same technology base, especially for XML parsing 286 .
[0106] Adapters
[0107] Each adapter's 274 primary function is to translate the communication that it receives from its client in its native protocol to the Liberate digital identity API. Clients make requests to adapters to perform certain operations such as getting and setting of data. These requests are decoded and handled by the adapter, and translated into digital identity API calls; data returned from the API calls is encoded and sent to the client. As mentioned, adapters may run in-process or out-of-process; the API is identical in either case.
[0108] Compared to in-process adapters, external ones offer advantages (independence of programming language; stability of external process) and disadvantages (potential performance penalty of extra network hop). In general, in-process adapters should be used where possible, for performance reasons.
[0109] Adapters that rely on HTTP use the same mechanism for decoding and handling the network traffic as the digital identity network adapter (namely an HTTP server such as Apache) 298 . A goal of the digital identity server is to use a single adapter to service all XML requests, be they from in-process or out-of-process adapters. To facilitate unification, a compatible XML format is adopted.
[0110] CORBA and LDAP adapters
[0111] The digital identity server does not provide native interfaces for CORBA or Lightweight Directory Access protocol (LDAP). Clients that use these protocols require special-purpose adapters. The adapters implement the appropriate Server type (CORBA or LDAP), but use digital identity protocols on the back end.
[0112] CORBA
[0113] The CORBA adapter is needed to support the User Data Manager, which is a CORBA Client (currently implemented as a Java applet). Like all CORBA servers, it supports an interface defined in an IDL. IDL has currently been defined for the digital identity engine consisting of about 40 operations, defined on 7 interfaces (object classes). This supports a particular object model, which has since been extended for digital identity. In order to make the new digital identity features accessible through CORBA, the IDL is extended. The adapter translates IDL calls into digital identity API calls.
[0114] The CORBA adapter may run either in-process or out-of-process with respect to the digital identity Engine. An in-process implementation links the digital identity Engine into the CORBA Server as a library, which is different from the method of running other in-process adapters, which are accessed through a web server interface. The out-of-process implementation uses the SDK and network adapter.
[0115] The Digital Identity Object Model
[0116] As shown in FIG. 3, there are three top-level object classes: Accounts 302 , Users 306 and Machines 304 . These three top-level object classes are collectively referred to as Entities. Individual Entities have a unique entityid, specified when the Entity is created. Each User 306 is associated with exactly one Account. Each Machine 304 is associated with exactly one Account. As illustrated by the 1 to N relationship an account 302 may have a plurality of users 306 . As illustrated by the 1 to M relationship, an account 302 may have a plurality of machines 304 . For example, a household CATV account 302 may include several family members as users 306 , and have more than one CATV converter 304 .
[0117] All Entities may have primitive Properties. Properties are typed; the current set of types is {string; integer; boolean; binary}. Besides the primitive Properties, Entities may have Collection Properties associated with them. Collections are structured objects—i.e., have primitive Properties of their own. Collections may have many Instances for a given Entity; each Instance has a unique instanceid, which can be used to access that Instance.
[0118] As shown in FIG. 5, the account entity is associated with one or more attributes 510 , services 516 and collections 508 . An account entity 502 stores the properties of the account and billing information.
[0119] Similarly, FIG. 6 illustrates the machine entity 604 being associated with one or more attributes 610 , services 616 and collections 608 . The machine entity 604 represents an interactive device.
[0120] Similarly, the user entity 706 is associated with one or more attributes 710 , services 716 and collections 708 . A user entity 706 represents the user of an interactive device or application. In addition, the user entity 706 is associative with one or more cookies 718 . As shown in FIG. 4, cookies have special Collection Properties, with particular semantics, such as name 406 , path 404 , domain 402 , value 410 , expiration 412 and security level 414 .
[0121] Besides being associated with particular Entities, Collection Properties may have values at the global (System) level. Customers may define additional Properties for Accounts, Users, Machines, or Collection Properties, and may define additional Collection Properties. Entities have Server Groups, which specify where their data is located. Users and Machines associated with an Account have the same Server Group as the account.
DIGITAL IDENTITY OBJECT MODEL
[0122] [0122]FIG. 8 is a hierarchical representation of the Digital identity object model. Various types of information are represented in the digital identity server to support the needs of administrators, applications, set-top boxes, and other users. The information is structured according to a particular model (schema), which reflects the world of Accounts, Machines, and Users. Information that is handled by the digital identity server can be accessed and manipulated in a variety of ways, including through CORBA, and from the settop box.
ENTITIES AND RELATIONSHIPS
[0123] The primary objects in the system are Entities 802 , which correspond to Accounts 806 , Machines 808 , and Users 810 . There are three subclasses of Entities to represent the three cases listed above:
[0124] Accounts: Represents a billing account. An Account may have multiple Machine and multiple User entities associated with it.
[0125] Machine: Represents a single set-top box. Each Machine object must always have an associated Account.
[0126] User: Represents a User on a set-top box. Each User object must always have an associated Account.
[0127] Standard UML notation is used to represent both the digital identity object model and the associated CORBA IDL. The boxes in FIG. 8 represent classes (CORBA interfaces) of which there are 7 in the system. Each box in FIG. 8 is divided into three regions; the top region shows the class name; the middle region shows the attributes that are defined in the base schema; the bottom region shows the operations (methods) that are defined in the CORBA IDL.
[0128] The lines among the boxes indicate relationships. The ones with arrowheads are generalizations; the others are associations, with the multiplicity indicated by the numbers at either end.
DIGITAL IDENTITY SERVER GROUPS
[0129] To improve scalability, network operators can create digital identity server groups. A deployment can have one or more digital identity server groups 902 , 904 , depending on how the network operator configures the system. Each server group 902 , 904 has its own configuration settings and its own database. The use of server groups is convenient when managing a large number of subscribers.
[0130] Besides a database for each server group, there is a single, shared digital identity system database 906 that can be accessed by every digital identity server. The system database 906 contains basic information for all subscribers, while each server group database 902 , 904 only contains information about the subscribers in that particular group.
DIGITAL IDENTITY ADAPTERS
[0131] Digital identity adapters 908 , 910 communicate with the digital identity servers 902 , 904 across an API 912 that provides a single point of access to all data in all digital identity servers. This provides the following benefits:
[0132] Different TV Navigator clients (such as TV Navigator Standard and Compact clients) can all access the same digital identity server or server groups.
[0133] Developers can create custom provisioning applications that use the services of the digital identity CORBA adapter. These applications can also interface to external billing, customer service, and subscriber management systems, to interoperate with legacy systems.
[0134] A simple graphical user interface is provided at the digital identity console 914 , which can access and modify persistent data stored in the digital identity servers. The digital identity console 914 is implemented as a CORBA client.
[0135] Through the provisioning plugin architecture, digital identity provides access to external back-end data stores, such as LDAP servers enabling system operators to access legacy data.
[0136] The digital identity architecture supports the development of new client adapters, as needed for emerging protocols.
[0137] Below are several examples of sample code for provisioning an account making requests and providing responses.
SAMPLE CODE FOR PROVISIONING AN ACCOUNT Transaction.open( ); Account johnsAccount = Account.create(“LondonServerGroup”); johnsAccount.setAttribute(“sysFirstName”, “John”); johnsAccount.setAttribute(“sysLastName”, “Smith”); Machine setTopBox1 = Machine.create(johnsAccount, “macAddr1”); Machine setTopBox2 = Machine.create(johnsAccount, “macAddr2”); User john = User.create(johnsAccount); john.setAttribute(“sysName”, “John”); john.setAttribute(“sysPassword”, “1234”); setTopBox1.addUser(john); setTobBox2.addUser(john); Transaction.commit( ); Example XML Request <XMSG> <AUTH CLASS =“USER” TYPE = “password” ID = “Ryan” TOKEN = “a secret”> <REQUEST OP = “GET”> <OBJ N = “/user” ID =“Ryan”/> </REQUEST> </AUTH> </XMSG> Example XML Response <XMSG> <RESPONSE OP = “GET” STATUS = “OK”> <OBJ N = “/user” ID = “Ryan”/> <AT N = “sysFirstName”>Ryan</AT> <AT N = “sysLastName”>King</AT> </OBJ></RESPONSE> </XMSG>
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Two-way digital media devices typically store digital identifying data that identify the user to providers of content and interactive data. In the case of a Web browser of a personal computer, the digital identity is stored in the form of a plurality of cookies that are used by respective web sites to personalize the web site experience for each particular user. When a user is at a different computer, the digital identifying data is not available. In addition, other types of interactive devices, such as CATV settop boxes, cell phones, PDAs and the like, may not have enough non-volatile memory (persistent storage) to store the digital identifying data. In order to provide users with a portable digital identity, a digital identity server is provided as a server node on the Internet, which retrieves digital identifying data and downloads such digital identifying data to any device upon request. In such manner, the user's digital identity is portable and available at any computer or other digital device that is being used. The system digital identity server permits devices without sufficient non-volatile memory storage to download a digital identity for temporary storage in volatile memory, thereby providing a digital identity in devices without non-volatile memory.
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BACKGROUND TO THE INVENTION
The present invention relates to hydraulic control apparatus for operating the support props of a mineral mining installation.
Known forms of control apparatus of the type with which the invention is concerned are described in German Patent Specifications P 27 49 312 and P 29 14 884. These apparatuses utilize manual-operable control valve devices which connect pressure fluid feed and return lines selectively to the working chambers of associated props. An automatic setting arrangement composed of further valve devices is designed to connect the prop chambers charged with fluid to extend the props to a pressure fluid source or to the pressure line once a threshold pressure is exceeded. The automatic setting arrangement acts independently of the control valve devices and ensures that a prop is adequately set against the roof even if one of the control valve devices is operated prematurely to disconnect the pressure source from the prop chamber. The threshold pressure at which the automatic setting arrangement comes into operation is made higher than that present in the prop chamber when the prop is being extended freely without contact with the roof and less than the desired setting pressure and that provided in the pressure feed line. In general, the props can be extended and retracted by operation of the control valve device(s) without the automatic setting arrangement coming into operation. This enables repairs and maintenance work and any back filling necessary in the event of roof falls to be performed without the automatic setting arrangement becoming affected. Generally, the threshold pressure at which the setting arrangement comes into operation is in the range 50 bars to 150 bars, e.g. 120 bars, while the pressure in the pressure feed line is significantly higher--typically above 300 bars and more usually in the range 350-450 bars.
One problem encountered with the known apparatuses, occurs when the props are subjected to pressure fluid to cause their retraction. During this operation pressure fluid in the working chambers of the props charged to produce their extension needs to pass back to the return line and it is possible that temporary fluctuations in the pressure in these chambers, caused by back pressure, could exceed the threshold pressure of the automatic setting system. In this event the retraction of the props will be prevented or hindered since the pressure source would be connected to the working chambers of the props instead of the return line.
A general object of the present invention is to provide an improved form of control apparatus.
SUMMARY OF THE INVENTION
The present invention relates to control apparatus comprising pressure fluid feed and return lines, at least one manually-operable control valve device for selectively connecting said feed and return lines to respective working chambers of a support prop and automatic setting means for automatically connecting the one working chamber of the prop which is charged with pressure fluid to effect extension of the prop to a source of pressure fluid when a predetermined threshold pressure in said one chamber is exceeded, said threshold pressure being lower than a desired setting pressure and higher than that which prevails in said one chamber which the prop is being extended.
In accordance with the invention means is provided for automatically disabling the automatic setting means when the control valve device connects the other working chamber of the prop to the pressure fluid feed line to effect prop retraction. This avoids the problems discussed hereinbefore when the automatic setting arrangement or means could inadvertently come into operation during prop retraction. Indeed with apparatus constructed in accordance with the invention a pressure head can build up in the first-mentioned working chamber during retraction which is above the threshold pressure of the setting means without the latter responding. The disabling means can take the form of a hydraulically operated valve which switches over when pressure fluid is passed to the other prop working chamber. This valve may constitute at least part of the automatic setting means.
Further non-return valves and at least one relief valve would normally be incorporated in the apparatus. Conveniently, the control valve device is connected to said one working chamber of the prop via a line incorporating a non-return valve and to said other working chamber via another line. A pressure-relief valve is connected between said lines and on the side of the non-return valve remote from the control valve device to relieve excessive pressure in the one working chamber. This non-return valve is then controlled hydraulically to open automatically when the line connected to the other working chamber is pressurized to effect prop retraction.
In one preferred construction the automatic setting means takes the form of a simple setting valve device which has a control piston designed to change its operating state once the threshold pressure is exceeded. This valve device can then adopt a state where connection is established therethrough between the source of pressure fluid, which may be the pressure fluid feed line, and the first-mentioned working chamber. The disabling means can then take the form of another control piston for the valve device which opposes the action of the first-mentioned control piston. This other control piston can be exposed to pressure in a line leading to the other prop working chamber to prevail over the first-mentioned control piston and cause the valve device to adopt a state where connection therethrough is blocked. The respective control pistons can be connected via conduits or lines to the prop working chambers. The piston may have differential working areas and/or supplementary spring force can cause the other control to prevail as aforesaid.
The invention also extends to a compact valve device with a housing containing a valve element, such as a ball, held against a seating by spring force to block connection between inlet and outlet ports leading to the prop working chamber used for extension and setting and to the pressure fluid source. Opposed control pistons having plungers can then act on the element in opposite senses. One control piston is supplemented by the spring force and is subjected to pressure when the other prop working chamber is likewise pressurized for retraction. The other control piston is subjected to pressure when the working chamber used for extension is charged and serves to lift the valve element off its seating against the spring force once the threshold pressure for automatic setting is exceeded. If both pistons are subjected to pressure of similar value the one piston prevails because of the spring force but this effect can be exhanced by making the working area of this one piston greater than that of the other piston.
A preferred embodiment of apparatus constructed in accordance with the invention comprises main pressure fluid feed and return lines; a manually-operable control valve device for selectively connecting the feed and return lines to respective first and second working chambers of the prop to effect extension and retraction thereof; a setting valve device connected to the first working chamber of the prop which is charged with fluid to effect extension of the prop; said setting valve device being settable to a first state where connection is established therethrough between said first working chamber and a pressure fluid source or a second state where connection is broken between said source and said first working chamber; a first control piston of the setting valve device connected to said first working chamber for causing the valve device to adopt said first state when exposed to pressure above a threshold signifying the prop is being set; a second control piston of the setting valve device connected to the second working chamber of the prop for opposing the action of the first control piston and for causing the setting valve device to adopt said second state when the second working chamber is charged with fluid to effect retraction of the prop.
The invention may be understood more readily, and various other aspects and features of the invention may become apparent, from consideration of the following description.
BRIEF DESCRIPTION OF DRAWINGS
An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawing, wherein:
FIG. 1 is a schematic representation of hydraulic control apparatus constructed in accordance with the invention and
FIG. 2 is a sectional view of a valve device for use in the apparatus shown in FIG. 1.
DESCRIPTION OF PREFERRED EMBODIMENTS
As shown in FIG. 1, control apparatus constructed in accordance with the invention has a valve device 11 connected by way of example through conduits or lines 13, 14 to the working chambers 10', 10" of a hydraulic prop 10 and to pressure fluid feed and return lines P.R. It is also possible to connect the valve device 11 to several props instead of a single prop as shown. The valve device 11 is capable of adopting one of three settings or states 0, 1, 2 depicted schematically by reference numerals in FIG. 1. The valve device 11 can employ a rotary slide valve actuated by a pivotable control lever 12 accessible from the exterior of a housing. The valve device 11 is provided with an automatic return mechanism--the so-called "dead man's handle"--which automatically brings the valve device 11 back into a neutral position 0 when the lever 12 is released. This neutral position 0 effectively blocks off the working chambers 10', 10" of the prop 10 from the pressure line P. In the state 0 as illustrated, the chamber 10" of the prop 10 is connected via the line 14 and the valve device 11 to the return line R. The chamber 10' is also connected to the return line via the line 13 and the valve device 11 but the presence of a non-return valve 17 maintains the prop properly set. If the valve device 11 is changed over to the state designated 1 the chamber 10' is connected to the pressure feed line P via the non-return valve 17, the line 13 and the valve device 11 which the chamber 10" is connected to the return line via the line 14 and the valve device 11. This setting state 1 thus initiates extension and then setting of the prop 10. With the valve device 11 set to the control state designated 2 the chamber 10' is connected to the return line R via the line 13 and the valve device 11 while the chamber 10" is connected to the pressure feed line P via the line 14 and the valve device 11. The non-return valve 17 is subjected to hydraulic control as indicated by the chain-dotted hydraulic control line 18. This line 18 connects the valve 17 to the line 14 so that the valve 17 is held open when the valve device 11 is set to the state 2 and the line 14 is thus connected to the pressure line P. This setting state 2 initiates positive retraction of the prop 1.
A pressure relief valve 15 of known construction is connected between the lines 13 and 14 on the side of the valve 17 feeding the chamber 10'. The valve device 15 is set to open at a predetermined excess pressure to thereby connect the prop chamber 10' directly to the line 14 and thence to the return line R should excessively higher pressure prevail in the chamber 10' with the valve device 11 in states 0 or 1. The valve device 15 is connected to the line 14 via a non-return valve 16.
The apparatus employs automatic setting means which includes a further valve device 19. This setting valve device 19 is connected via a line to the pressure line P as shown or to another source of pressure fluid possibly provided by the same pump as line P. A non-return valve is incorporated in the line 20. The valve device 19 is connected via a line 21 and a non-return valve 22 to the working chamber 10' of the prop 10. The valve device 19 is capable of adopting two operating conditions or states designated a and b in the drawing. In state a, connection between the lines 20, 21 is blocked while in state b, connection is established between the lines 20, 21. The valve device 19 is controlled hydraulically by means of pistons 23, 25. The piston 23 is connected via a hydraulic control line 24 to the working chamber 10' and the piston 25, which operates in opposition to the piston 23, is connected via a hydraulic control line 26 to the line 14. The action of the piston 25 is supplemented by the force of a closure spring 27.
As mentioned previously, in order to set the prop 10 the valve device 11 is changed into the state 1 so that the line 13 connects the chamber 10' to the pressure feed line P while the line 14 connects the chamber 10" to the return line R. As the piston 10"' of the prop 10 moves outwardly of its cylinder to raise the prop, the pressure in the chamber 10' remains more or less constant at about 50 bars or less. When the roof-engaging structure borne by the prop 10 makes contact with the roof of the mine working, however, the pressure builds up in the chamber 10' provided that the valve device 11 remains in the state 1. If the device 11 is prematurely changed to state 0 the pressure prevailing in the chamber 10' may be considerably lower than that considered to be safe for adequate setting. The automatic setting system shown in FIG. 1 is designed to overcome this problem and comes into operation at a certain pre-selected pressure above 50 bars and usually in the range 50-150 bars or more preferably 100-130 bars. Once the lower threshold limit set by the automatic setting system is exceeded by the pressure in the chamber 10' thus signifying the onset of setting, this pressure acts via the line 24 on the piston 23 to change the state of the valve device 19 from state a to state b. As a result the chamber 10' is now connected to the pressure line P by way of the device 19. Thus the valve device 11 is by-passed and the prop 10 can be adequately set. In order to retract the prop 10, the valve device 11 is changed to the state 2 in which the line 13 is connected to the return line R via the opened valve 17 while the line 14 is connected to the pressure line P. In this condition, the chamber 10" of the prop is subjected to hydraulic pressure while the chamber 10' is relieved and the piston 10"' of the prop 10 is retracted. The pressure fluid in the chamber 10' is driven out via the line 13 and the non-return valve 17, which is actuated by the control line 18 and vents through the valve device 11. Any back pressure or pressure head which exceeds the setting pressure of the valve device 19 and which may build up in the line 13 leading to the return line R would force the valve device 19 to switch over to position b to connect the chamber 10' with the pressure line P. This would then inhibit the desired retraction of the prop 10. In order to eliminate this problem the valve device 19 has its piston 25 connected to the line 14 via the line 26 so that during retraction when the line 14 is subjected to pressure, the valve device 19 is held in state a. The control piston 25 in conjunction with the spring 27 is thus capable of exerting a greater force than the control piston 23 even if back pressure builds up in the line 13 during prop retraction.
FIG. 2 shows a preferred constructional arrangement for the valve device 19. As shown, the valve device 19 has a housing or block 28 containing a valve closure element in the form of a ball 29 which is urged against a seating 30 by the closure spring 27. A chamber 31 in the housing 28 contains the spring 27 and the closure element 29 and a port or opening 32 leads out from the chamber 31 to permit connection with the line 20. This port 32 thus forms an inlet to the valve device 19. Another chamber 37 contains the control piston 25 which acts on the valve closure element 29 via a guided push rod passing through the spring 27 to urge the element 29 against the seating 30 (state a FIG. 1). A port 38 leads to the chamber 37 and permits connection with the line 26. At the opposite end and in a somewhat larger chamber 33 the piston 23 is provided. The piston 23 has a push rod 34 capable of acting on the valve closure element 29 to lift the element 29 off its seating 30 (state b FIG. 1). Access to the chamber 33 is provided by a port 35 which would be connected to the line 24. A further port 36 leads to a chamber next to the seating 30 and acts as an outlet from the device 19. The port 36 would be connected to the pressure line 21. It can be seen that the valve element 29 is held on its seating 30 to block connection between the ports 32, 36 by the force of the spring 27 and by pressure which may prevail in the line leading to the port 38 to act on the piston 25. The valve closure element 29 can however be raised off its seating to thereby open connection between the ports 32, 36 by means of pressure acting on the piston 23 via the port 35.
When the device 11 is set to state 2 to retract the prop 10 the pressure in the line 14 acts via the line 26 on the piston 25 to supplement the force of the spring 27 thereby to overcome the force exerted by the piston 23 to ensure that the valve closure element 29 is held on the seating 30 to close the connection between the ports 32, 36 thereby to bring the valve device to the state a.
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Hydraulic control apparatus serves to operate roof support props of a mineral mining installation. An automatic setting arrangement with a valve device ensures the props become set against the roof with a high uniform force by connecting a prop pressure chamber to a pressure fluid source once a threshold pressure is exceeded signifying the prop has been extended. To disable the automatic setting arrangement during prop retraction the valve device thereof is provided with a control piston which is subjected to pressure during retraction to oppose the action of another control piston which responds to the threshold pressure.
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FIELD OF THE INVENTION
[0001] This invention relates to the prevention of copper corrosion during the integrated circuit manufacturing process when copper is used as the interconnect material.
BACKGROUND OF THE INVENTION
[0002] As the performance of semiconductor integrated circuits improves, copper is replacing aluminum and becoming the material of choice for interconnects due to its lower resistivity and better electro-migration resistance. However, unlike aluminum which forms a native protective oxide layer, copper is more susceptible to corrosion. The copper corrosion can occur during the copper interconnect manufacturing processes due to its exposure to the chemical or ambient environment, and it can be further enhanced by the exposure to the light (photovoltaic effect) due to its connection to p-n junctions on the wafer. The copper corrosion usually happens between copper CMP, where a flesh copper surface is exposed, and the next process step, such as the passivation layer or etch stop layer (SiN, SiC) deposition. In the prior art, one way to reduce copper corrosion is through the use of corrosion inhibitor, such as Benzotriazole (BTA), in the manufacturing process.
[0003] The difficulty in using BTA for corrosion prevention is in controlling the applied amount due to the fact that the BTA applied during or post CMP process on the wafer surface has to be removed in the vacuum deposition tool prior to the application of the passivation layer. If the applied amount of BTA is not enough or the uniformity of the applied BTA layer is not good then the desired effect of corrosion prevention cannot be achieved. On the other hand, if too much BTA is applied to the wafer surface then it is very difficult to remove it completely before the next process step. BTA residue on the wafer will often cause defectivity and impact device yield and reliability. Additionally, the removal of BTA in the vacuum deposition tool has resulted in high maintenance costs and long tool down times. Another way to reduce copper corrosion, particularly the corrosion due to photovoltaic effect is to darken the environment during the manufacturing process. However, this increases the manufacture cost, is difficult to implement, and it does not completely eliminate corrosion. Yet another method to reduce copper corrosion is to impose a time window between copper CMP and the next process step. The controlled time delay between the two processes is simply to reduce as much as possible the exposure time of the copper interconnect to ambient environment to minimize the corrosion. This increases the manufacture cost and is difficult to implement; and yet it does not completely elimination copper corrosion. Hence, there is a need to further improve corrosion resistance of copper in the integrated circuits manufacturing process. Furthermore, it is highly desirable to replace the BTA with a layer or layers that can be applied more uniformly, have higher corrosion resistance than the copper interconnect, can selectively coat the copper interconnects, and does not need to be removed at the next passivation layer deposition.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] The drawing is a flow chart illustrating the process flow of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0005] The use of displacement plating to selectively coat copper interconnects with higher corrosion resistant metal or metal alloy layers during the manufacturing process of copper interconnects will minimize the occurrence of copper interconnect corrosion. The present invention is described with reference to the attached FIGURE. The FIGURE is not drawn to scale and it is provided merely to illustrate the instant invention. Several aspects of the invention are described below with reference to example applications for illustration. It should be understood that numerous specific details, relationships, and methods are set forth to provide a full understanding of the invention. One skilled in the relevant art, however, will readily recognize that the invention can be practiced without one or more of the specific details or with other methods. In other instances, well-known structures or operations are not shown in detail to avoid obscuring the invention.
[0006] The drawing is a flow chart illustrating the process flow of the present invention. The present invention is used during the fabrication of an integrated circuit. Due to the difficulty of etching copper in plasma etch chamber, the damascene process is typically used to create copper wiring. In the damascene process, openings in the dielectric insolating layer are formed with a patterning and etching process. In a single damascene structure, the openings are trench or via, and in a dual damascene structure, the openings are usually trench plus via. However, a dual damascene structure could be several trenches or several vias to a trench. These openings are then coated with a barrier layer, such as Ta, TaN, to prevent copper diffusion into the dielectric layer and to improve adhesion between the copper interconnect and the dielectric layer, followed by the formation of the copper seed layer. The openings are then filled with bulk copper through, for example, an electroplating process. The chemical mechanical polishing (CMP) process is then used to remove excess portions of copper and to planarize the surface. The polished wafers are then cleaned to remove slurry, polishing by-product, and corrosion inhibitors. The corrosion inhibitors generally protect the copper surface during CMP and post CMP clean. However, after post CMP clean, when the corrosion inhibitor has been removed from the wafer surface, it is found that copper is particularly susceptible to corrosion.
[0007] After post CMP clean, the copper surface is exposed within the fabrication environment. Copper is susceptible to corrosion in such an ambient environment. The issue is further aggravated by photo induced copper corrosion. The exposure of the P-N junctions to light causes the photo induced copper corrosion/re-deposition due to the photovoltaic effect since the copper is connected to the P-N junction. Such events may result in yield loss and reliability problems.
[0008] The problem of corrosion can be reduced or eliminated by forming a higher corrosion resistant layer or layers with a displacement plating process at the top surface of the copper interconnects. It is within the scope of this invention to use any displacement metal or alloy for the coating layers. For example, the metal used for the displacement plating layers may be Palladium, Platinum, Rhodium, Ruthenium, Gold, Silver, Lead, Nickel, Cadmium, Tin, or other noble metals and their alloys.
[0009] The advantage of the current invention in preventing copper corrosion is multifaceted. First, the displacement metal (such as Pd) is selectively coated on the top surface of copper, not in other places, such as dielectric layer. Second, since the coating itself is conductive; it does not need to be removed in a later process step. Third, the thickness of the displacement plating is driven by the oxidation potential difference between the coating metal and copper, therefore its thickness is self-limiting and the final thickness can be well controlled. Fourth, the coating process has excellent coverage, therefore uniform corrosion resistant layers can be applied on top of the copper interconnects.
[0010] In the best mode application, it's desirable to have a monolayer of corrosion resisting metal as the displacement plating layer. However, any thickness that can provide sufficient corrosion prevention of the copper interconnect—without significantly increasing metal resistance—is within the scope of the invention. In the best mode application, the thickness of displacement metal is below 100 Å for a trench depth around 2000 Å to 5000 Å.
[0011] Referring again to the drawing, a dielectric layer is formed (step 10 ) over the entire wafer during the fabrication of the interconnect structure. The dielectric material may be applied to the substrate with a Chemical Vapor Deposition (“CVD”) or a spin-on manufacturing process. The dielectric layer is then patterned (using photoresist) and etched (step 20 ) to form a trench and/or via for the copper interconnects. A barrier metal (such as Ta, TaN or TaN/Ta bilayer) is deposited (step 30 ) to prevent copper diffusion into the dielectric layer and also to improve the adhesion between the copper interconnect and the dielectric layer, and is followed by the copper seed. Then bulk copper is deposited (step 40 ) onto the wafer to fill trenches and/or vias typically through an electrochemical deposition process. A Chemical Mechanical Polishing (CMP) process is used to remove the excessive copper and to planarize the surface (step 50 ).
[0012] A post-CMP clean (step 60 ) is then performed to remove slurry residues, corrosion inhibitors, such as Benzotriazole (“BTA”), and other by-products from the polished surface. The post-CMP clean is typically first performed in a megasonic cleaner using Tetramethyl Ammonium Hydroxide (“TMAH”) as the cleaning agent. That is followed by brush clean using chemical agent, such as ammonium citrate.
[0013] In accordance with the invention, a coating of displacement plating is now formed (step 70 ) on the metal interconnects. In the best mode application, an immersion into the displacement plating solution can be utilized to subject the semiconductor wafer to the displacement reaction. However, other displacement plating processes such as spraying the displacement plating solution on to the wafer surface is also within the scope of this invention. In the example application the displacement plating process is performed using the same clean-up hood as the Post-CMP clean processes in order to prevent corrosion during wafer transfer.
[0014] The displacement reaction process forms a self-limiting passivation layer on all exposed copper surfaces However, various thicknesses of displacement plating are within the scope of this invention. For example, if a very thin coating of plating is desired then the plating process may be discontinued before the displacement reaction becomes self-limited; or a different displacement plating solution with lower metal concentrations can be used. The plating process may even be modified to create thick coats of plating. In the best mode application the thickness of displacement plating layer is determined by the requirements of minimized corrosion occurrence of copper interconnect. The thickness of the displacement plating depends on the plating solution concentration and the displacement reaction time. Example displacement plating solutions are: a) cadmium oxide and potassium hydroxide, b)hydrogen tetrachloroaurate ethanol, c) lead monoxide and sodium cyanide and sodium hydroxide, d) nickel sulfate and ammonium nickel sulfate and sodium thiosulfate, e) palladium chloride and hydrochloric acid, f) chloroplatinic acid and hydrochloric acid, g) rhodium sulfate and sulfuric acid, h) ruthenium nitrosyl chloride and hydrochloric acid, i) silver nitrate and ammonia and sodium thiosulfate, or j) stannous chloride and thiourea and sulfuric acid. However, other plating solutions are within the scope of this invention. The selection of the displacement solutions is dependent on the metal or metal alloy layers and its compatibility with semiconductor manufacturing processes.
[0015] It should be noted that the displacement plating process only coats the copper area. That is because the copper displaces the noble metal from its solution causing only the metal interconnects to be coated. As an example, if the metal interconnects contain copper and the displacement plating solution contains palladium then the displacement reaction would generally be: Cu+Pd 2+ -->Cu 2+ +Pd. The result is that palladium will be selectively coated on top of the copper interconnect.
[0016] The fabrication process now continues until the interconnect structure is complete (step 80 ). It should be noted that it is within the scope of this invention to form displacement plating on the metal interconnects of any interconnect layer.
[0017] While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. Numerous changes to the disclosed embodiments can be made in accordance with the disclosure herein without departing from the spirit or scope of the invention. Thus, the breadth and scope of the present invention should not be limited by any of the above described embodiments. Rather, the scope of the invention should be defined in accordance with the following claims and their equivalents.
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An embodiment of the invention is a method to reduce the copper corrosion of copper interconnects by forming 70 at least one conductive displacement plating layer on the copper interconnects. Another embodiment of the invention is a method to eliminate the copper corrosion of copper interconnects by forming 70 at least one conductive displacement plating layer on the copper interconnects.
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BACKGROUND OF THE INVENTION
The trend in the circuit protection industry is currently toward complete circuit protection which is accomplished by the addition of supplemental protection apparatus to standard overcurrent protective devices, such as molded case circuit breakers. In the past, when such auxiliary protection apparatus or other circuit breaker accessories were combined with a standard circuit breaker, the accessories were usually custom-installed at the point of manufacture. The combined protective device, when later installed in the field, could not be externally accessed for inspection, replacement or repair without destroying the integrity of the circuit breaker interior. U.S. Pat. No. 4,894,631 describes a molded case circuit breaker containing an actuator-accessory unit which provides a wide variety of circuit protection accessory options. This patent is incorporated herein for purposes of reference and should be reviewed for its description of the state-of-the-art of such circuit breakers and accessory devices.
U.S. Pat. No. 4,913,503 describes a reset mechanism for a lower ampere-rated circuit interrupter usually employed as a "branch" circuit interrupter within industrial power distribution systems downstream from a higher-rated "main" circuit interrupter. When electronic trip units are used within the higher-rated circuits, a "flux shifter" tripping device is used to articulate the interrupter operating mechanism upon overcurrent conditions. One such flux shifter device is described within U.S. Pat. No. 4,641,117 which Patent is incorporated herein for purposes of reference. With the heavier operating mechanism springs used within higher-rated circuit interrupters, the actuator-accessory unit, per se, is incapable of generating sufficient tripping force to articulate the operating mechanism, such that additional tripping force is required. The additional tripping force is provided by a supplemental tripping mechanism which interacts with the actuator-accessory unit through a sequential resetting arrangement to insure that the actuator-accessory unit becomes reset before the main operating mechanism is reset. The operation of the sequential latching arrangement is described within U.S. patent application Ser. No. 518,672 filed May 3, 1990 entitled "Actuator-Accessory Reset Arrangement for Molded Case Interrupter or Electric Switch" which Application is incorporated herein for purposes of reference.
One purpose of this invention is to describe the supplemental tripping mechanism and its interaction with the sequential latching arrangement to interrupt circuit current by direct operation of the actuator-accessory unit.
SUMMARY OF THE INVENTION
An integrated protection unit which includes overcurrent protection along with auxiliary accessory function within a common enclosure contains an accessory cover for access to the selected accessory components to allow field installation of the accessory components. A combined actuator-accessory unit provides overcurrent, shunt trip or undervoltage release functions and is arranged within one part of the enclosure. The circuit interrupter operating mechanism interfaces with a sequential resetting arrangement by means of a sequence drive lever rotatably connected with the operating mechanism cradle. A supplemental tripping arrangement cooperates with the actuator-accessory unit to articulate the operating mechanism by operation of the actuator-accessory unit, per se.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top perspective view of a molded case circuit interrupter containing the supplemental tripping system in accordance with the invention;
FIG. 2 is a cutaway side view of the circuit interrupter of FIG. 1 with the operating mechanism in a "TRIPPED" condition;
FIG. 2A is an enlarged side view of the tripping system shown in FIG. 2;
FIG. 3 is a cutaway side view of the circuit interrupter of FIG. 1 with the operating mechanism in a "LATCHED" condition;
FIG. 3A is an enlarged side view of the tripping system show FIG. 3;
FIG. 4 is a cutaway side view of the circuit interrupter of FIG. 1 with the operating mechanism in a "CLOSED" condition; and
FIG. 4A is an enlarged side view of the tripping system shown in FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A higher-rated circuit interrupter 10, as described earlier, is depicted in FIG. 1 and consists of a molded plastic case 11 to which a molded plastic cover 12 is fixedly secured. An accessory cover 13 is attached to the circuit interrupter cover and provides access to an electronic trip unit 14 and an actuator-accessory unit 15. An operating handle 16 extends through the circuit interrupter cover by means of an access slot 17 and provides manual intervention to turn the circuit interrupter contacts 19, 20 between their open and closed positions as best seen by referring now to the followings FIGS. 2-4A.
The contacts 19, 20 within the case 11 of the circuit interrupter 10 are depicted in the "TRIPPED" position of the circuit interrupter operating mechanism generally designated at 9 and which includes a cradle 28 for latching the movable contact arm 18 between its "CLOSED" and "OPEN" positions. In the TRIPPED position indicated in FIGS. 2, 2A, the movable contact arm 18 and attached movable contact 19 are automatically driven away from the fixed contact 20 and fixed contact support 21 by articulation of the operating mechanism upon the occurrence of an overcurrent condition, by means of the electronic trip unit. A good description of one such electronic trip unit is found within U.S. Pat. No. 4,658,323 while a general description of a circuit breaker operating mechanism is found within U.S. Pat. No. 4,736,174 both Patents are incorporated herein for purposes of reference. A combined actuator-accessory module for interfacing between the operating mechanism and the electronic trip unit is described in U.S. Pat. No. 833,563 which Patent is also incorporated herein for reference purposes. The operating handle 16, cradle 28 and operating mechanism sideframe 30 are depicted in phantom for purposes of clarity. The cradle 28 is operatively attached to the mechanism sideframe by means of a cradle pivot pin 29 such as described in U.S. Pat. Nos. 4,679,016 and 4,698,903 which Patents are incorporated herein for reference purposes. In returning the circuit breaker operating mechanism and contacts to their operable CLOSED positions, the actuator-accessory latch 34 and trip cam 23 associated with the actuator-accessory unit 15 within the circuit breaker cover 12 shown earlier in FIG. 1, are depicted herein in phantom in order to show the interaction between the circuit breaker operating mechanism 9, the sequential resetting arrangement 8, and the supplemental tripping system 7 in accordance with the invention. The relationship between the circuit breaker operating mechanism and the sequential resetting system within the case 11 is controlled by means of a sequence driver 26 arranged on the end of the cradle pivot pin. As the operating handle 16 and handle yoke 27 are moved sequentially counterclockwise to rotate the cradle 28 and reset the circuit breaker operating mechanism, the sequence driver 26 interacts with the sequential resetting system 8 by striking the drive roller 33 on the sequence lever 25 which in turn rotates the sequence lever about a pivot pin 32 bringing the latch pin 41 on the trip cam 23 into engagement with the actuator-accessory latch 34 as described within aforementioned U.S. patent application Ser. No. 518,67. The sequence lever 25 is attached to the sideframe by means of the pivot pin 32 and is biased to a rest position by means of a torsion spring 37. An arcuate cut-out 25A on the sequence lever 25 abuts against a post 31 on the sideframe to accurately return the sequence lever to its initial reset position under the return bias of the torsion spring 37. The interaction between the trip bar 22, trip cam 23 and the actuator-accessory latch 34 during the reset function of a circuit interrupter operating mechanism is described within aforementioned U.S. Pat. No. 4,913,503.
In the event that the actuator-accessory unit remains de-energized, the actuator-accessory latch 34 is unable to retain the latch pin 41 on the trip cam 23 thereby causing the trip cam 23 to strike against the angled end 40A of the trip latch 40 which in turn rotates the opposite end 40B of the trip latch out of abutment with the arcuate end 35B of the trip link 35 to allow the opposite end 35A of the trip link to strike the trip bar 22 by rotation about its pivot pin 38 under the urgence of the powerful trip spring 36. In the event that the circuit breaker operating mechanism and the actuator-accessory unit are in their latched or reset conditions, and an event occurs which causes the actuator-accessory unit to become operational, the circuit breaker operating mechanism is tripped by direct operation of the actuator-accessory unit in that the actuator-accessory latch 34 releases the latch pin 41 to rotate the trip cam 23, trip latch 40 and trip link 35 in the manner just described.
To reset the sequential reset system 8 and supplemental tripping system 7 before the main operating mechanism 9 can be reset, the operating handle 16 is moved counterclockwise to the position indicated in FIGS. 3, 3A which rotates the cam-shaped end 26A of the sequence driver 26 up against drive roller 33 on the sequence lever 25 and moves the cam-shaped end 24 of the sequence lever 25 against the pin 39A on the reset lever 39. This, in turn, rotates the reset lever 39 and reset driver 42 in the counterclockwise direction to charge the trip spring 36 to its fully charged position. The reset lever and reset driver move as a unit by the operative connection between the reset lever and reset driver by means of the reset link 43 and pins 44, 45. The trip spring 36 provides interference between the angled end 42A of the reset driver 42 and the end 35B of the trip link 35. This interference causes the reset driver and trip link to move as one unit.
The circuit breaker operating mechanism is brought to its closed condition by movement of the operating handle 16 to the position shown in FIGS. 4, 4A whereby the handle yoke 27 has driven the movable contact arm 18 and attached movable contact 19 into abutment with the fixed contact 20. The sequence driver 26 assumes the position shown in FIGS. 4, 4A with the cam-shaped end 26A of the sequence driver 26 against the drive roller 33 and with the cam-shaped end 24 of the sequence lever 25 abutting against the pin 39A on the reset lever 39. The actuator-accessory latch 34 retains the trip cam 23 by means of the latch pin 41. When the actuator-accessory unit is energized to trip the circuit breaker operating mechanism, the actuator latch 34 rotates in a clockwise direction to release the latch pin 41 and thereby allow the trip cam 23 to move the angled end 40A of the trip latch 40 thereby allowing the trip latch to rotate in a clockwise direction and release the end 35B of the trip link 35 from contact with the end 40B of the trip latch 40 and allow the opposite end 35A of the trip link 35 to strike the trip bar 22 and propel the trip bar in the indicated direction to release the circuit breaker operating mechanism. The arcuate shape of the trip link 35 depicted at 35C allows the end 40B of the trip latch 40 to rotate clockwise away from the end 35B of the trip link without interfering with the rotation of the trip link in the counterclockwise direction. The reset lever spring 47 allows the reset lever 39 and trip link 35 to rotate as a unit back to the reset position indicated earlier in FIG. 2.
The supplemental tripping mechanism is also employed with circuit interrupters utilizing an accessory unit, per se in the circuit interrupter cover in place of an actuator unit or combined actuator-accessory unit to articulate the circuit breaker operating mechanism. An undervoltage release accessory unit is one type of an accessory unit that could be used with the supplemental tripping mechanism in accordance with the invention. One such undervoltage release accessory unit is described within U.S. Pat. No. 4,801,907.
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An integrated protection unit is a circuit breaker which includes basic overcurrent protection facility along with selective electrical accessories. A molded plastic accessory access cover secured to the integrated protection unit cover protects the accessory components contained within the integrated protection unit cover from the environment. A combined overcurrent trip actuator and multiple accessory unit can be field-installed within the integrated protection unit. The combined actuator-accessory unit includes electronic control circuitry for the accessories along with supplemental trip and reset interface components. The reset mechanism allows the actuator-accessory unit to become reset without interfering with the operation of the integrated protection unit. The trip interface components allow the circuit interrupter to interrupt a protected circuit by operation of the actuator-accessory unit.
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BACKGROUND OF THE INVENTION
This invention relates to devices for the treatment of heart disease and particularly to endoarterial prostheses, which are commonly called stents. More particularly, the invention relates to improved metal stents that are coated with expanded polytetrafluoroethylene (ePTFE) in an expandable form.
A focus of recent development work in the treatment of heart disease has been directed to various forms of expandable stents. Stents are generally tube shaped intravascular devices which are placed within a blood vessel to structurally hold open the vessel. The device can be used to maintain the patency of a blood vessel immediately after intravascular treatments and can be used to reduce the likelihood of development of restenosis.
Catheter systems are frequently used to deliver stents to the desired stenotic location. Stents delivered via catheter systems therefore often require extreme flexibility so as to be capable of being transported through varying and tortuous turns and diameters of the vessel pathway prior to arriving at the desired site. Expandable stents are so designed.
Expandable stents are delivered in a collapsed form to the stenotic region and are expanded into the vessel wall thereafter, typically by self expansion properties or by force from an underlying inflated balloon. Most balloon expandable stents can be divided into coil or tubular designs. The tubular stents are usually constructed from a metal tube cut into special pattern, which expands by the force of underlying balloon. The stent typically is crimped on an expandable balloon at the distal end of a catheter assembly by the manufacture or by the operator. After travel in reduced form to the stenotic site, the stent is expanded into the vessel wall by inflating the balloon.
Often referred to as memory stents, self expanding stents may be composed of metals, like nitinol, that are in the elastic or pesudo-elastic range of deformation. Such stents are restrained, typically by a sheath, during travel to the lesion and are sprung open against the vessel wall after the restraint is removed. Since the metal is in its “spring” or “pesudo-elastic” state, it will continue to apply outwardly supportive force to the vessel wall after the stent has been deployed. These stents are available, for example, in mesh designs or, for example, as a chain of corrugated rings.
Stents can also be configured in lesion specific designs, and include a radio-opague marker or coating, and may be in the form of a stent-graft. Stent-grafts are constructed with a prosthetic vascular graft material (eg, e-PTFE or Dacron). The graft material separates the blood flow from the native luminal surface, which may be atherosclerotic, aneurysmal, and/or injured from angioplasty. Grafts have been employed to cover aneurysms, perforations, and degenerated vein graft lesions.
Stents formed from metallic materials are used for strength and rigidity to aid in holding open the targeted vessel wall. Various metals such as stainless steel 316L, tantalum, platinum, nitinol in its martensite form, and alloys formed with cobalt and chromium have often been used to construct such stents whether in self or balloon-expandable form. Metal stents can be formed in a variety of configurations such as helically wound wire stents, wire mesh stents, weaved wire stents, metallic serpentine stents, or in a chain of corrugated rings.
Metallic serpentine stents, for example, not only provide strength and rigidity once implanted they also are designed sufficiently flexible for traveling through the tortuous pathways of the vessel route prior to arrival at the stenotic site. Additionally, such stents can be made expandable by way of expandable balloon, memory after compression, or otherwise.
Stents that possess a metal surface, however, suffer from a number disadvantages. They may possess burrs, nicks, or sharp ends resulting in insertion and travel resistance.
Also, metallic expandable stents, such as wire mesh and serpentine designs, for example, do not possess uniformly solid tubular walls. Although generally cylindrical in overall shape, the walls of such stents are perforated often in more of a framework design of wire-like elements connected together or in a weave design of cross threaded wire. In either case, the perforated design not only provides expandability, it also provides flexibility for traveling to the stenotic site.
Radial expansion of metal stents usually results in expansion of the spaces between the wires or the struts comprising the perforated stent wall. Such enlarged spaces at the stenotic site provide greater openings for ingrowth of thrombotic material that if great enough may lead to invasion of the flow path and result in restriction of fluid flow or even complete blockage. In addition, a stent with such anchoring ingrowth may prove difficult to remove.
Advantages of employing polytetrafluoroethylene (PTFE) as a stent cover material are well known to those skilled in the art. PTFE is a thermoplastic polymer that is chemically inert, is biocompatable, and has a smooth, flexible, and low-resistance surface to aid the stent insertion procedure. Expanded polytetrafluoroethylene (ePTFE) possesses micropores and may be available in an expandable form. The micropores provide mechanical bonding locations for underlying melt thermoplastics and provide openings on the surface of the cover for limited tissue ingrowth and helpful endoluminal anchoring. The expandable form of ePTFE is expandable facilitating expansion of an underlying metal stent.
ePTFE can be made in a variety of thicknesses, but alone can be insufficiently rigid to hold open a vessel. Stents made of only ePTFE would require relatively thick walls and thus relatively small openings for fluid flow. Moreover, ePTFE possesses elastic properties so that expansion of a stent made from only ePTFE may not remain in an expanded condition after an expandable balloon, for example, is deflated and withdrawn. While offering a smooth low friction surface, other stent materials are often preferred for superior structural performance.
The benefits of partial covering and total encapsulation of a stent body with ePTFE material has been recognized. Covered with expandable ePTFE film, a metal stent can be expandable, biocompatible, and can be sufficiently flexible and present a smooth low-friction surface for endoluminal travel. Such a stent may also be sufficiently structurally rigid to support a vessel wall and encourage beneficial microendotheial growth. Additionally, expandable ePTFE as a cover material can provide unbroken cover before, during, and after expansion of the underlying metallic stent body. The integrity of the ePTFE cover can therefore be maintained during stent expansion to continue shielding and protecting the vessel wall from the underlying metal. Additionally, the stent covering of expandable ePTFE serves to protect the patency of the vessel itself by inhibiting thrombotic growth through the large perforations of the expanded metallic stent body.
It is well known, however, that PTFE, ePTFE, and expandable ePTFE, by virtue of their non-stick properties, can not be easily adhered, whether by mechanical bonding, chemical bonding, or otherwise, directly to a surface. Techniques of sodium etching, mechanical roughening, and plasma treating have been proposed in efforts to improve bonding strength between metal and PTFE material. These processes, however, are not practical to cover stents because adhesion of any of the aforementioned forms of PTFE to the metal surface is relatively weak and because such treatment increases the roughness or polarity of the surface which may then cause undesired trauma or cellular response.
For example, twisting, bending, and expansion of the stent body may cause such bonds to break thus loosening or even dislodging the covering from the stent body. Dislodgment of the stent cover while operational could be troublesome.
Rapid growth in the use of endovascular stents suggests improved clinical outcomes with their use. Coronary stents have significantly improved the outcome of percutaneous treatment of coronary stenoses by reducing immediate complications and long-term restenosis. The stent appears to be an advantageous percutaneous device that effectively treats abrupt vessel occlusion by virtue of its ability to support the vessel wall, prevent intimal flap prolapse into the lumen, and prevent elastic recoil of the arterial wall, thus providing an open vessel where laminar blood flow is maintained and the patency of the arterial lumen is preserved.
There has long existed a need for a metallic stent covered with a secure ePTFE cover. There has also long existed a need for a method to bond thermoplastic polymers to a stent with a metal surface. The present invention satisfies this need.
SUMMARY OF THE INVENTION
The invention is directed to an improved stent that has an exterior metal surface which is covered with a primer containing both an active agent for chemical bonding to the metal and a thermoplastic polymer for melting into, and forming a mechanical bond with, a top coating of expandable ePTFE. This invention is also directed to a method for adhering expandable ePTFE to a metal prosthesis.
The improved stent is formed from one or more of a variety of metals including stainless steel, titanium, silver, gold, tantalum, nickel-titanium, manganese, cobalt-chromium, and nickel. Alternatively, the improved stent may be formed with an exterior metal surface from a variety of other materials capable of maintaining its material and mechanical properties after exposure to the temperatures and pressures disclosed herein. Any stent pattern is useable with the present invention coatings.
Applied to the metal surface is a primer containing both a chemically reactive agent for chemical bonding to the metal surface and a thermoplastic polymer for melting into a top coating of thermoplastic polymer. Once applied, the chemically reactive agent of the primer reacts and bonds to the metal surface. The top coating is applied over the primer and the portion of the primer containing the thermoplastic polymer is heated sufficiently to melt forming a mechanical bond with the top coating of expandable ePTFE.
In the event superior adhesion of expandable ePTFE to the stent is desired, the thermoplastic polymer contained in the primer includes fluorinated ethylene propylene (FEP), a copolymer, over which is applied a layer of FEP. Use of primer is necessary as neither FEP nor ePTFE alone adhere adequately to a variety of metals including stainless steel. The over layer of FEP and the primer are then heated to combine with the thermoplastic polymer contained in the primer. The FEP and primer layers are then cooled prior to application of the the ePTFE top coating.
After the expandable ePTFE top coating is applied, the FEP is then heated to above its melting point, but below the melting point of the ePTFE. Not exceeding the melt temperature of the ePTFE preserves the microporous structure and elasticity of the expandable ePTFE coating. With the elevated temperature, pressure is simultaneously applied to the expandable ePTFE to force the melted FEP into the micropores of the expandable ePTFE.
Each of the coatings herein described can be applied by spray, dip, brush-on, plasma deposition, or application of preformed film or any technique known to those skilled in the art. Furthermore, selected portions of the stent may be utilized, for example, for application of one or more of the coatings. In one embodiment, for example, only the annular ring ends of the stent are coated with primer and FEP, and a preformed sleeve of expandable ePTFE is pulled or rolled over the stent body and adhered thereto by application of heat and pressure. Adherence to only the ends of the stent body can provide an outer covering of expandable ePTFE without adherence of the ePTFE to the entire outer surface of the stent body. The unadhered expandable ePTFE film, while not bonded to the stent body, is free to be physically supported by, and expanded in conformance with, the underlying metal stent body.
In another embodiment, expandable ePTFE films encapsulate the entire stent body by bonding inner and outer sleeves of expandable ePTFE to the stent body to wholly cover the stent sealing the metal from exposure to any body fluid or tissue. In yet another embodiment, all surfaces of the stent body, including the surfaces between interstitial gaps in the stent wall, are coated by a covering of primer, FEP, and expandable ePTFE.
In addition, multiple layers of primer, FEP and expandable ePTFE may be applied as desired to achieve desired coating thickness. Expandable ePTFE is preferred for its microporus and expandable properties. Where expansion is not required, ePTFE may be substituted. Where neither expansion nor a superior bond is required PTFE may be substituted. In addition, other melt thermoplastic polymers may be used in lieu of FEP and expandable ePTFE depending upon the performance desired. Furthermore, an ePTFE cover may be adhered to a stent or, similarly, to a medical prosthesis with a metallic surface. Attaching a film of ePTFE in the form of a graft to a metal stent by adhesion as disclosed is also within the scope of the invention.
Other features and advantages of the invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the features of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a metal stent body of the present invention laid flat.
FIG. 2 is a perspective view of the stent body shown in FIG. 1 formed into a tubular metal stent body encased in a partially broken away tubular sleeve of expandable ePTFE according to the present invention.
FIG. 2A is an enlarged transverse cross-sectional view taken along line 2 A— 2 A of FIG. 2 .
FIG. 2B is an enlarged transverse cross-sectional view taken along line 2 B— 2 B of FIG. 2 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Expandable metallic stents are well known to those in the art. There exists a wide variety of stent configurations for implanting in human vessels. Perforated metal stents, for example, have been widely utilized. Although utilitarian in providing rigidity, resistence to crushing, and durability, perforated metal stents are often also expandable in vivo. Expansion of the stent usually results in the enlargement of the perforations in the stent walls. Without a barrier, these enlarged perforations, however, provide openings for tissue ingrowth into the fluid flow path. Substantial tissue ingrowth may result in partial or total occlusion of the fluid pathway and increase the difficulty of removing the occlusion.
Referring to FIG. 1, the stent body 10 of the present invention is one of expandable form although a non-expandable stent may be employed. FIG. 1 illustrates a flattened metal stent body 10 of serpentine pattern that includes a plurality of cylindrical elements 23 of undulating peaks 25 and valleys 26 connected together by transitional elements 24 . Each cylindrical element 23 is connected by way of interconnecting links 27 . The length of the stent body of the present embodiment is determined by the length of the peaks, valleys, transitional elements, interconnecting links, and the number of cylindrical elements connected together. The stent body can be made from a variety of metals including but not limited to gold, silver, nickel-titanium, titanium, tantalum, stainless steel, and cobalt-chromium. Manufacture of such stent bodies is known to those in the art.
FIG. 2 illustrates a stent 20 of the present invention that includes a tubular expandable metal stent body 10 of serpentine design consisting of cylindrical elements 23 , of peaks 25 , valleys 26 , and transitional elements 24 . The cylindrical elements are connected together by one or more connecting links 27 between adjacent cylindrical elements. Expandable metal stents, like the present invention, have an outer diameter of about 1.5 mm in the unexpanded condition, and can be expanded to an outer diameter of 4.5 mm or more for coronary applications, and much larger for other applications (e.g., peripheral or biliary). Typical wall thickness of an expandable stent is about 0.10 mm. The stent body of the present embodiment is comprised of metal, however, a stent body having a metallic exterior surface may also be utilized.
The tubular stent body in the subject embodiment is in the unexpanded state within a top coating of expandable ePTFE in the form of a pre-formed tubular sleeve 30 of expandable ePTFE film having an inner surface 32 and an outer surface 34 . The sleeve of expandable ePTFE film is expandable to conform, once adhered to the stent body, to the underlying stent body during travel to the stenotic site. In addition, the expandable ePTFE material is capable of providing unbroken cover during and after radial expansion of the underlying stent body to its permanently deployed form. Manufacture of expandable ePTFE film in the form of a tubular sleeve will be known to those in the art.
Referring to FIG. 2A telescoped in concentric relationship over the tubular stent is a tubular sleeve 30 of expandable ePTFE. The ePTFE sleeve has a circumferential inner surface 32 and a circumferential outer surface 34 . The inner surface of the sleeve is adhered to the transitional elements 24 by way of application of a primer layer 35 over which is applied a layer of fluorinated ethylene propylene (FEP) 36 . After application of the primer and FEP layers in the present embodiment, the sleeve is positioned over the stent body and the FEP is melted and forced by application of pressure into the inner surface of the sleeve forming a mechanical bond between the sleeve and the FEP.
The primer layer 35 when applied must include a chemically active component to chemically react with the metallic surface of the transitional elements 24 and to form a chemical bond between the primer and the metal of the stent body. Dupont 850-300/VM7799, for example, contains chromic and phosphoric acid which, when exposed to high temperature, will react to form such a bond. The primer will also preferably include FEP, but may include PTFE, perfluoroalkoxy (PFA), or other melt thermoplastic polymer which, when applied and heated as part of the primer, will be will be available for subsequent mechanical bonding to a separate over layer of FEP 36 or to a top coating of ePTFE 30 . A mixing of the thermoplastics together may also occur should they be melted, and may include chemical bonding such as with Van der Walls forces. An acceptable weight ratio of active component to polymer is between 80 percent active component to 20 percent polymer to between 60 percent active component to 40 percent polymer.
In the present embodiment, the primer layer 35 is applied to the end of the stent body. In other embodiments it may be desirable to coat a different portion of the stent body. The primer may be sprayed, dipped, brushed, or plasma deposited onto the metal stent body to achieve a thickness of between 0.010 and 0.050 mm, preferably 0.025 mm. Once applied, a primer such as Dupont 850-300/VM7799, for example, requires heat to form sufficient chemical bonding with the metal surface of the stent body. Heating may be accomplished by inductive, resistive, or other means of heating known to those in the art to a temperature of between 500° Fahrenheit and 700° Fahrenheit for a period of 1 to 30 minutes at standard atmospheric pressure. The heat is then removed and the primer is allowed to cool and solidify.
In the current embodiment, an intermediate FEP layer 36 , such as DuPont 850-200 clear, is applied over the primer layer 35 . The FEP layer can be sprayed, dipped, brushed on, over the primer layer to a thickness of between 0.025 and 0.130 mm thick, preferably 0.025 mm. The FEP layer can be applied over the primer layer by plasma deposition, but the DuPont 850-200 clear is not suitable for this process so another FEP compound would be used. The primer and FEP layers are then heated to a temperature of between 550° Fahrenheit and 620° Fahrenheit for a period of 1 to 30 minutes at standard atmospheric pressure so that both the FEP layer and polymer contained in the primer layer may melt to form an adhering mechanical bond. The heat is then removed and the FEP is allowed to cool and solidify.
In the present embodiment, the pre-formed tubular sleeve 30 of ePTFE of 0.025 to 0.260 mm, preferably 0.076 mm thickness, is then applied over the FEP layer 36 . This can be accomplished, for example, by sliding or rolling the sleeve over the stent body. Once the sleeve is positioned over the stent body the temperature is raised by heating to between 550° Fahrenheit and 620° Fahrenheit for a period of 5 to 60 seconds at a pressure of between 5 psi and 50 psi. As the melting point of FEP is lower than that of ePTFE, this temperature is sufficient to melt the underlying FEP, but is not so hot as to substantially melt the top coating of expandable ePTFE film. The melting of ePTFE for a prolonged period of time may substantially change its crystalline structure and alter its properties including its micropores. Although not required for some level of bonding to the ePTFE, the simultaneous application of pressure with heat forces the melted FEP into superior mechanical bonding contact with the surface and micropores of the ePTFE. The ePTFE film may tear if pressure in excess of 50 psi is applied.
Referring to FIG. 2B, the medial portion of the tubular expandable ePTFE sleeve 30 is not adhered on the inner surface 32 to the stent body. This disconnection of the sleeve at the intermediate length of the stent body leaves the two components free to move somewhat relative to one another, as shown in FIG. 2A, thus enhancing the flexibility and uniformity of expansion adjacent the end of the stent body.
Application of ePTFE is not limited to the form of a pre-formed tubular sleeve 30 . For example, a film of ePTFE can be rolled into a tubular sleeve. The primer for ePTFE material may also be applied in the form of spray, dip, brush-on, or plasma deposited coating and adhered to a metal surface such as a stent body, other forms of medical prostheses, or to any other metallic surface such as a wire, for example, before or after the wire is formed into the shape of a stent or other medical device.
In another embodiment, the primer layer, including FEP, is adhered to a metal stent body over which a layer of FEP is applied. However, it is only after both the FEP-containing primer layer and the FEP over layer are applied to the stent body that the primer layer is heated sufficiently to react with the metal surface and to melt the FEP. The primer and FEP layers are then heated to a temperature of between 550° Fahrenheit and 620° Fahrenheit for a period of 1 to 30 minutes at standard atmospheric pressure so that a melting of the FEP layer and polymer contained in the primer layer may melt together to form an adhering mechanical bond. The heat is then removed and the FEP is allowed to cool and solidify before application of the top coating of ePTFE.
As will be appreciated by those skilled in the art, the method of fabricating the stent has broad applications. This method may be employed for treating numerous different metallic implant devices. The method may be employed to treat a medical prosthesis having an exterior metallic surface by applying a primer including a chemically reactive agent, to facilitate chemical bonding of the primer to the metallic surface, and a thermoplastic polymer to facilitate mechanical bonding to a top coating including ePTFE, heating the primer layer to chemically bond it to the surface, applying a top coating including ePTFE to the primer, and heating the thermoplastic contained in the primer layer to bond with the ePTFE coating. Also disclosed herein is a method to apply a layer containing FEP between the primer layer and the top coating of ePTFE.
The present invention satisfies a great need for a metal stent with a secure and expandable ePTFE cover. Adherence of ePTFE to a stent body, through the use of a chemically reactive primer, however, has not been heretofore disclosed. Additionally, the present invention satisfies the need for a method to fabricate such a stent. The benefits of the present invention are many to those in the art with a need for improved adhesion of ePTFE to the metal surface of a medical prosthesis.
An expandable metal stent can be formed to possess a low-insertion profile, flexibility for traveling the tortuous pathway to the stenotic site, and a structurally strong framework after expansion to hold open the vessel at the targeted site. A stent covered with a secure coating of expandable ePTFE further provides a smooth low-friction surface to aid in the insertion procedure, is biocompatible, and is expandable to provide unbroken cover before, during, and after expansion of the underlying stent body. The integrity of the expandable ePTFE cover can therefore be maintained during stent expansion and continue, after expansion, shielding and protecting the vessel wall from the underlying metal. In other words, a stent covered with expandable ePTFE serves to protect the patency of the vessel since the perforations in the stent are covered so by the material so that plaque does not push through (prolapse) the perforations into the vessel. Furthermore, the micropores contained within the ePTFE provide small openings facilitating beneficial microendothelial tissue ingrowth that serves to anchor the ePTFE film to the vessel wall. During the formation of the present invention, the micropores also facilitate improved mechanical bonding to the FEP applied prior to the ePTFE top coating.
The embodiments heretofore discussed are in no way intended to limit the scope of the invention. Various changes and improvements may also be made to the invention without departing from the scope thereof.
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A metal prosthesis or metallic stent having a coating of expandable polytetrafluoroethylene (ePTFE) adhered thereto by way of an intermediate laminate containing a primer chemically bonded to the metallic surface over which FEP, a copolymer, is applied.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
The field of the invention relates to fluid dispensing mechanisms and, more particularly, to an improved dispensing apparatus which may be miniaturized and which is capable of delivering precisely controlled quantities of fluid.
2. Brief Description of the Prior Art
There are a number of known designs for dispensing fluids such as adhesives, sealants, and the like at accurately controlled flow rates, in accurate quantities, and for accurate placement on a receiving surface.
In certain designs, fluid is introduced under pressure to a reservoir and dispensed upon movement of a valve member off a valve seat. U.S. Pat. Nos. 4,930,669 and 4,955,514 disclose two such designs. Each design is sealless, which is highly advantageous for dispensing fluids which tend to leak through and/or destroy conventional seals.
Another type of dispensing apparatus is disclosed in U.S. Pat. No. 4,858,789. This design allows the positive displacement of precise quantities of fluid from a reservoir. All three patented devices discussed above employ a deformable diaphragm for isolating the reservoir from the mechanism which actuates the valve, thereby preventing the undesirable entry of product into the mechanism.
Other types of dispensers are disclosed in U.S. Pat. Nos. 4,066,188, 4,066,845, 4,099,653 and 4,126,321. The first three patented dispensers are designed primarily for dispensing hot, viscous fluids, while the latter is designed for use as a spray gun. Each employs a bellows seal for isolating a fluid reservoir from an actuating mechanism.
U.S. Pat. No. 3,871,558 discloses an apparatus for dispensing viscous products such as liquid soap via positive displacement. The products are confined by a bellows-type membrane.
There are many different types of fluids which require the use of a dispensing apparatus. Such fluids have a very broad range of viscosities, curing properties, and other characteristics which may preclude the use of certain types of dispensers. Cyanoacrylates, for example, of relatively low viscosities tend to diffuse with polymers and then cure. These properties make the use of dynamic seals in a dispenser very disadvantageous. If high pressure within the fluid reservoir is required, diaphragm seals become disadvantageous as the pressure against such seals must be overcome in order to move the stem or slide to which the valve member is secured.
Fluid dispensers may also be used in a wide variety of applications, some of which require incorporation of the dispenser within sophisticated machinery. Others may require the ability to manipulate the dispenser manually. The ability to manufacture a dispenser which is small in size and easily manipulated by hand is important in many applications. As the fluid reservoirs of many dispensers are supplied with fluid through fittings in the reservoir walls, the dispensers are rather difficult to handle as the fittings and associated tubing are obstructions which must be avoided.
The ability to miniaturize existing dispenser designs is often limited due to the manner in which fluid is supplied to the reservoir, as described above. Other internal structures in many dispensers also severely limit the extent to which they can be miniaturized. As small size and light weight are advantageous features in a number of applications, many prior art dispensers are of only limited utility.
SUMMARY OF THE INVENTION
The present invention is directed to a dispensing apparatus which is usable for dispensing a wide variety of fluids. The structure of the apparatus is such that it lends itself to miniaturization. It is also capable of withstanding high pressure and dispensing precise quantities of fluid. The fluid may be displaced from a reservoir within the apparatus either due to pressure within the reservoir or via positive displacement.
The dispensing apparatus according to the invention includes a housing which defines a reservoir for containing the fluid material to be dispensed. It further includes a discharge port through which the material in the reservoir may exit. An elongate slide is positioned within the housing. The slide includes a longitudinal passage extending at least partially therethrough and a port which provides fluid communication between the passage and reservoir. The reservoir may accordingly be filled by supplying fluid through the passage in the slide. A longitudinally expandable seal, such as a bellows seal, is positioned within the reservoir. The seal is secured to the slide. A support is provided within the housing, the slide extending through and preferably supported by the support. The seal is also secured to the supporting means, thereby preventing fluid from entering the supporting means. Valve means, responsive to the slide, are provided for controlling the dispensing of fluid through the discharge port.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top perspective view of a dispensing apparatus according to the invention;
FIG. 2 is a sectional view thereof taken along line 2--2 in FIG. 1;
FIG. 3 is a sectional view thereof showing the apparatus in the dispensing mode;
FIG. 4 is an enlarged, sectional view of the discharge end of the apparatus according to an alternative embodiment of the invention;
FIG. 5 is an exploded, perspective view of the dispensing apparatus according to the invention, and
FIG. 6 is a sectional view of an alternative embodiment of the invention which dispenses fluid via positive displacement.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the Figures, FIGS. 1-3 and 5 illustrate a first embodiment of the invention wherein fluid is dispensed due to internal pressure provided within a fluid reservoir. The apparatus 10 shown in these Figures includes a substantially cylindrical housing 12, a substantially cylindrical slide 14 extending through and substantially coaxial with the longitudinal axis of the housing, and a funnel-shaped nozzle 16 secured to one end of the housing. All of these elements may be made from polypropylene or other corrosion-resistant material. The slide may alternatively be made from an acetal resin as sold under the trademark DELRIN, or stainless steel.
Referring to FIGS. 2-3, a reservoir 18 is defined in part by the walls of the housing 12. Fluid is preferably supplied to the reservoir through a passage 20 extending along the longitudinal axis of the slide 14. Fluid exits the passage via one or more ports 22 extending through the wall of the slide. The ports 22 are preferably oriented towards the discharge end of the apparatus.
The passage 20 within the slide extends from the rear end of the slide to the ports 22 or a point slightly beyond the ports. The front end of the slide is accordingly closed.
The front, or discharge end of the apparatus is preferably designed to allow a selection of valving mechanisms. A valve seat 24 is positioned within the housing and is secured to the inner surface of the housing 12. The valve seat includes a passage having one end defined by a frustoconical surface 24A and a second end defined by adjoining frustoconical surfaces 24B, 24C. The slide 14 includes a frustoconical end portion 14A corresponding in dimension to one of the surfaces 24B of the rear end of the valve seat. The slide and valve seat may accordingly function as a needle valve assembly, not unlike that disclosed in U.S. Pat. No. 3,463,363. Such an assembly may be preferable in some applications where the apparatus is controlled by a programmable controller.
In accordance with the generally preferred embodiment of the invention, valving is accomplished by means of a valve member 26 which is sealingly engageable with the frustoconical surface 24A at the front end of the valve seal 24. The valve member may be substantially spherical, as shown, or of other configurations which allow such sealing engagement. The valve member is preferably made from polypropylene, while the valve seat is stainless steel. Like all of the components of the apparatus which are exposed to the fluid material to be dispensed, the valve member and valve seat must be resistant to the highly corrosive materials which are commonly dispensed by this type of apparatus.
The use of a valve member 26 as shown in FIGS. 2-4 not only allows fluid to be dispensed in precise quantities when moved away from the valve seat, but also creates a partial vacuum when retracted. This prevents stringing and/or dripping of the fluid as discussed in U.S. Pat. No. 4,930,669. The valve member 26 includes a threaded opening 28 (FIG. 5) aligned with the longitudinal axis of the slide 20. The slide includes a stem 30 having a threaded end 30A (FIG. 5) to which the valve member is secured. The valve member may alternatively be secured to the stem by an adhesive or a snap fitting. The rear end 30B (FIG. 5) of the stem is unthreaded and is positioned within the slide passage 20. The stem may be secured to the slide by an adhesive, or may simply be press fit therein. In an alternative embodiment of the invention as shown in FIG. 4, the stem 30' is formed integrally with the slide 14'.
A first adapter 32 is threadably secured to one end of the housing 12. The adapter adjoins the valve seat 24, and includes a partially threaded, axial passage 34 through which fluid from the valve seat area may exit. The nozzle 16 is secured to a second adapter 35 which has a threaded end extending within the threaded portion of the first adapter. The second adapter includes an axial passage which allows fluid to pass from the passage 34 in the first adapter 32 to the conical passage in the nozzle.
The rear end of the housing 12 includes an end wall 12A and a cylindrical, axial projection 12B through which the slide 14 extends. A cylindrical member 36 is secured to the inner surface of the housing near the rear end. A slide support 38, which is preferably made from a heat-conductive material such as stainless steel, is secured to the cylindrical member 36 and extends along the longitudinal axis of the housing towards the discharge end thereof. The slide 14 is slidably supported by the slide support 38 and the axial projection 12B of the housing.
A heat-conductive ring 40 is fixedly secured to the slide between the slide support 38 and the outlet ports 22. The ring is preferably made from stainless steel or other material which is resistant to corrosive materials. It may be formed as an integral part of the slide if the slide is also made of a heat-conductive material. In either event, it may be considered a part of the slide.
A generally cylindrical bellows seal 42 is secured at one end to an axial-projection 38A extending from the slide support 38 and at its opposite end to the ring 40. While clamping assemblies may be employed to secure the ends of the bellows seal, such assemblies are preferably avoided if a miniaturized assembly is desired. The bellows seal 42 is preferably made from fluorinated ethylene-propylene, which is commonly sold under the trademark TEFLON. In order to secure it to the slide support 38 and ring 40, a thin coating of fluorinated ethylene-propylene may be first applied to the support and ring. The ends of the seal are positioned over these elements, which are then heated from within until the coatings and the ends of the seal are fused. Upon cooling, the bellows seal is thereby secured in a leak-proof manner. If clamps are used, they are preferably made from a material such as tantalum which is highly resistant to corrosion.
A more preferred way of securing the bellows seal to the slide support and ring is through the use of epoxy. The bellows seal is ammonia etched, and the slide support and ring sand blasted prior to the application of the epoxy. A low viscosity, two part epoxy such as MEGABOND 17102 is one epoxy which may be successfully employed. MEGABOND 17102 is a product of Loctite Corporation of Newington, Conn. The product includes an epoxy resin and polymercaptan hardener, and exhibits rapid curing.
Another alternative for securing the bellows seal to the slide support is to manufacture the slide support and bellows seal as an integral assembly. Both elements could be made from TEFLON or other suitable material as a single molded piece.
In operation, fluid is introduced to the reservoir 18 through the passage 20 within the slide 14. Assuming the valve member 26 is not engaging the valve seat 24, the reservoir and nozzle 16 can be filled with fluid. Once this has been accomplished, fluid may be dispensed with high accuracy either by a continuous flow or drop by drop. As a maximum stroke of only about twenty to thirty thousandths of an inch is required to cause the valve member 26 to move sufficiently off the valve seat 24, only a short corrugated section is required between the ends of the bellows seal 42. Maximum flows are typically achieved in the apparatus with a displacement of only about ten thousandths of an inch from the valve seat. Small drops can be generated repeatedly by reciprocation of the slide 14 by the actuator while maintaining high fluid pressure within the reservoir 18. A bellows seal having a three eighths inch bore and a wall thickness between 0.015-0.020 inches has a hoop strength sufficient to withstand about 400 psi. This is more than sufficient for most, if not all applications. Even when the slide is reciprocated repeatedly for drop by drop dispensing of fluid, only minimal turbulence occurs within the reservoir. This prevents the formation of bubbles in the fluid. As the slide reciprocates, fluid is dispensed through the nozzle when the valve member 26 is moved off the valve seat 24, and partially sucked back into the nozzle when the valve member moves towards the valve seat. Unwanted dripping from the nozzle is accordingly prevented. The reservoir stays full as dispensed fluid is replaced by fluid introduced through the slide passage 20.
Referring now to FIG. 6, an alternative embodiment of the invention which operates via positive displacement is shown. The apparatus 10" includes many of the same elements as that shown in FIGS. 1-5, which have been designated by the same numerals as employed therein. The slide 14" includes a passage 20" which allows fluid to enter a reservoir 18" through a pair of radially extending ports 22". A valve seat 24" is provided at the discharge end of the apparatus. Like the valve seat 24 employed in the previously discussed apparatus, it includes a conical surface 25A" capable of making sealing contact with the valve member 26". The valve member is not secured to the slide in this embodiment, and accordingly is only indirectly responsive to movement of the slide. The opposite end of the valve seat, however, defines a cylindrical chamber 50. As shown in FIG. 6, the valve seat 24" may be made from polypropylene, in which case the valve member can be stainless steel. These elements can alternatively be made from other materials as described above. A resilient sealing ring 52 is secured to, or formed integrally with, the front end of the slide 14". The sealing ring is capable of making sealing contact with the walls of the chamber 50.
The valve member 26" is maintained in sealing contact with the conical surface 24A" of the valve seat 24" by a retainer 54. The retainer is urged rearwardly by a coil spring 56.
As the stroke of a positive displacement pump is considerably longer than the stroke of the apparatus discussed previously, the bellows seal 42" must be capable of greater axial expansion than is necessary in this apparatus. As shown in FIG. 6, the seal includes more corrugations to allow the slide 14" to move a distance at least as great as the axial length of the chamber 50. The bellows seal is secured directly to the slide by a metallic ring 40 at one end, the other end thereof being secured to a metallic, heat-conducting support 58 which closes off the rear end of housing 12. Both the ring and support may be made from stainless steel.
In operation, fluid is introduced to the reservoir through the passage 20" and ports 22" within the slide 14". The actuator 48 causes the slide to reciprocate at a selected rate. During the forward stroke, the sealing ring 52 is moved into sealing contact with the walls of the chamber 50. As the slide continues to move forwardly, the sealing ring causes the contents of the chamber to be displaced towards the nozzle 16, thereby causing the valve member to be displaced from the valve seat. A corresponding volume of material is dispensed by the nozzle. The rearward stroke of the slide causes the sealing ring 52 to move outside the chamber 50. The valve member is moved back into sealing engagement with the valve seat at this time by the spring and retainer. As fluid is supplied under pressure through the slide, the reservoir 18 and chamber 50 are refilled prior to the next forward stroke.
Although illustrative embodiments of the present invention have been described herein with reference to accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be effected therein by one skilled in the art without departing from the scope or spirit of the invention.
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A dispensing apparatus capable of dispensing a wide variety of fluids, such as adhesives, is provided. The structure of the apparatus allows it to be miniaturized, thereby facilitating its use for many applications. The apparatus includes a cylindrical housing in which a slide is mounted. The housing includes a fluid reservoir which is supplied with pressurized fluid. A longitudinal passage extends through the slide for providing this fluid to the reservoir. A bellow seal is employed for sealing off an actuating mechanism from the reservoir. The seal is connected between the slide and a support fixedly mounted to the housing. A valve mechanism is provided at one end of the housing for controlling the flow of fluid from the reservoir. The valve mechanism is directly or indirectly responsive to the slide. Fluid may be caused to flow through the valve mechanism either by fluid pressure or by positive displacement.
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BACKGROUND OF THE INVENTION
In the machine weaving and knitting of fabric, defects occur due to missed stitches, loops and knots, apparatus malfunctioning, misalignment, or other reasons, and such defects, if occasionally occurring at random, are accepted as an economic necessity. However, frequently recurring defects such as produced by broken needles or apparatus, snags, etc., will cause a fabric machine to produce unacceptable material, and if the malfunction is not quickly remedied considerable scrap material is produced, and the likelihood of more serious damage to the knitting or weaving machine is present. Previously, most machine knitting and weaving fabric was visibly inspected, but due to the fact that one operator was responsible for a number of machines considerable material waste was produced due to breakage or malfunction.
Defect detection apparatus has been developed for fabric producing machines, and such apparatus may use light reflection techniques for scanning fabric as shown in U.S. Pat. Nos. 3,160,759; 3,589,816; 3,786,265; 4,057,351; 4,075,498 and 4,103,177. Additionally, it is known to use scanning apparatus employing light frequencies other than visible frequencies and infrared and ultraviolet band frequencies have been employed as shown in U.S. Pat. Nos. 3,206,606; 3,325,649; 3,551,678 and 3,994,586.
Inspection apparatus such as that shown in the aforementioned patents is capable of sensing defects, however, such prior art devices do not have the capability to determine when the rate of occurrence of defects is acceptable or objectionable, and such apparatus which terminates knitting or weaving machine operation upon the sensing of a single defect reduces the machine's output to unacceptable low levels. There is the need for automatic fabric inspection apparatus which is capable of analyzing the defect characteristics and determining when the rate of defect occurances is tolerable and intolerable with respect to the rate of production and the quality of product desired. Prior art devices are incapable of meeting this need.
It is an object of the invention to provide fabric defect detection apparatus capable of detecting fabric defects and producing a signal wherein the number of defects occurring may be counted and retained.
A further object of the invention is to provide fabric defect detection apparatus utilizing infrared band scanning wherein fabric defects produce an electronic signal which is retained and counted, and timing apparatus is associated with the counting and retaining apparatus whereby a control signal is produced upon a predetermined number of defects occurring within a predetermined time interval so as to permit a given quality of product to be automatically maintained.
An additional object of the invention is to provide fabric defect detection apparatus capable of simultaneously scanning a signficant portion of the fabric wherein an electronic signal is produced upon a defect being detected, the apparatus being capable of recognizing the same defect upon being repetitiously sensed, and rejecting such repetitious sensing of a common defect as a plurality of defects for machine control purposes.
A further object of the invention is to provide fabric defect detection apparatus which is electronically controlled, is capable of retaining and counting defect signals, and uitlizes timer apparatus wherein the number of defects occurring in a predetermined time frame are sensed, the timer apparatus being initiated by a defect occurring, and the timer apparatus being reset upon termination of the predetermined time interval.
In the practice of the invention a sensing head of elongated length, such as 5 inches, is located adjacent a moving fabric which has just been knitted or woven by conventional fabric producing apparatus. The fabric being sensed may be moving as a linear web, or the fabric may be in the form of a tube which is rotating. The sensing apparatus is located adjacent the newly manufactured fabric and includes an infrared light source illuminating the portion of the fabric being sensed by infrared light detecting means. The detecting means consists of a block having a plurality of light receiving openings defined therein, and a sensitive, electronic, infrared, light detector being located adjacent each light passage wherein the passing of a defect past a fabric portion reflecting light into a given passage will cause a variation in the amount of light reflected into that passage producing an electronic variation in the light receiving sensor to produce an electronic signal.
The electronic signal produced due to a defect passing the sensor is amplified, compared with a background control signal, filtered, and electronically counted. The electronic counting apparatus is also associated with an electronic timer whose time frame is initiated by the first counted defect being sensed, and as subsequent defects are signaled during an initiated time frame such defects are counted and if the number of defects occurring within the predetermined time frame is greater than a predetermined number the apparatus will be automatically stopped, and adjustments will be made by the operator to correct the problem.
The electronic timer includes means for varying the duration of the time frame during which defects are counted, and thus, it will be appreciated that the apparatus is capable of closely regulating the quality of the fabric being produced in that the number of defects acceptable within a predetermined time interval regulates the quality of the product, and should the rate of defect occurrence exceed that desired the apparatus will automatically shut down and not produce scrap material. The fact that the apparatus is capable of continually determining and evaluating the quality of the fabric being manufactured prevents excessive attention to the equipment, as is the case with fabric defect detection devices which stop the knitting or weaving machine upon a single defect occurring.
The defect detection apparatus also includes means for analyzing the defect signals it receives in that repetitive signals may mean that the sensor is repeatedly detecting the same defect, as when the advance of the fabric is less than the length of the sensing array, and the circuit of the invention would count such signals as a single defect and thereby prevent unnecessary machine shut-down.
The circuit of the defect detection system of the invention includes means for automatically sensing the reflecting characteristics of the fabric being sensed to reflect infrared light and automatic background control means are used to modify the circuit with respect to this fabric characteristic so as to achieve a uniformity of circuit operation regardless of the reflectance of the fabric being sensed.
The defect detection apparatus includes means for analyzing the defect signals it receives, in that repetitive signals may mean that the sensor is repeatedly detecting the same defect, e.g. a run, and the circuit of the invention would shut down the machine to prevent production of unacceptable material.
The defect detection system also includes signal producing means for counting the total number of defects that occur, and also is conscious of repetitive defects for terminating machine operation. Likewise, the circuit may include a large hole detector wherein a single large defect such as produced by a major machine malfunction can be quickly detected to deactivate the fabric producing machine.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned objects and advantages of the invention will be appreciated from the following description and accompanying drawings wherein:
FIG. 1 is a schematic, elevational view of a typical defect detection apparatus in accord with the invention,
FIG. 2 is a rear elevational view of a sensing head in accord with the invention,
FIG. 3 is a plan view of the sensing head,
FIG. 4 is an elevational sectional view taken through Section IV--IV of FIG. 2, illustrating the infrared light receiving passages,
FIG. 5 is a front elevational view of the sensing block,
FIG. 6 is an illustrative view of the sensing pattern on the fabric,
FIG. 7 is a circuit diagram partially illustrating the electronic circuit of a defect detection system in accord with the invention,
FIG. 8 is an additional figure illustrating the electronic circuit of the invention, and
FIG. 9 is a partial circuit diagram illustrating a circuit modification.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In FIG. 1 a typical installation of a fabric defect detection system in accord with the invention as used with a knitting machine is shown. The knitting machine, not shown, by means of typical knitting apparatus produces a woven fabric tube 10 which axially moves in a vertical manner and rotates about a vertical axis simultaneously moving in the directions indicated by the arrows.
The defect detection system includes a sensing head block 12 which is mounted adjacent the fabric tube 10 and the apparatus also includes a light source 14, preferably producing light within the infrared frequency band, to illuminate the portion of the fabric immediately adjacent the sensing head 12. The sensing head block is of a generally rectangular configuration having a front end face 16 disposed adjacent to the fabric being inspected. The block 12 is internally provided with a plurality of light receiving passages 18, FIG. 4, each terminating at an opening at the intersection with the block face 16. Adjacent passages 18 are angularly related to each other in the manner appreciated from FIG. 4, and extention of the passages 18 beyond the face 16 results in a viewing pattern as shown in FIG. 6 consisting of a plurality of contingent circular area 20 defining a line approximately five inches in length whereby a five inch axial portion of the knitted fabric tube is being simultaneously sensed.
As the infrared light 14 is illuminating the fabric at the location being sensed by the head 12, the light being reflected from the fabric will enter the passages 18, and at the end of each passage is located an infrared detector 22 which comprises a photo transistor having uniform electrical conducting characteristics as long as the amount of light entering the detector is uniform. Upon a fabric defect passing the head, the reflected light entering at least one of the passages 18 will be momentarialy affected due to the defect, and the amount of light will be either reduced or increased slightly. This variation in the amount of reflected infrared light entering a passage 19 will be immediately sensed by the associated detector 22 and produce an electronic signal. The detectors 22 are connected in parallel, and although sensors are associated with an elongated sensing head the movement of a single defect past the head will be immediately discerned and produce the electronic signal.
The circuit associated with the defect detection apparatus of the invention is illustrated in FIGS. 7 and 8, and will now be explained in detail:
The conductor 24 is attached to the output of the sensing head 12, and this signal is put into an AC coupled amplifier circuit generally indicated at 26 which produces a 20 d.b. gain. This circuit includes the voltage comparator 28, and the operational amplifier 30 and the amplified circuit produces a signal transmitted to the voltage comparator 28. The voltage comparator 28, in addition to receiving the amplified signal from the defect detection head 12, also is receiving a background threshhold voltage from the operational amplifier 32 proportional to the reflectance of the fabric. The operational amplifiers 32 and 34 constitute the automatic background control circuit, and this circuit receives its input from a phototransistor 22' receiving reflected light through a head passage 18. This phototransistor may constitute one of the phototransistors 22 utilized for defect detection, and transmits a voltage into operational amplifier 34 proportional to the amount of infrared light reflected from the fabric. This background voltage is amplified by amplifier 34 producing a DC level in conductor 36 proportional to the amount of reflected light. Potentiometer 38 is a voltage offset adjustment which compensates for the offset voltages of the operational amplifier 34, and this potentiometer permits the output to be balanced. The conductor 36 transmits a DC signal proportional to the reflected light to operational amplifier 32 and the resistor 40 and capacitor 42 smooths out the high frequency variation of the DC signal and operational amplifier 32 constitutes a unity gain buffer and potentiometer 44 permits a portion of this output threshold signal to be transmitted to the voltage comparator 28. At conductor 46 a positive threshold voltage is produced. If the signal is above the threshold voltage at conductor 46 the comparator output voltage at 48 is high, and this will indicate a fabric defect.
To filter out extraneous noise a hex debouncer 50, FIG. 8, receives the output of voltage comparator 28 through a Schmitt trigger 52 which accelerates the logic transition time to produce a definite signal. The hex debouncer 50 functions as a filter to determine if the signal is of sufficient pulse width to be interpreted as a fabric defect. The pulse input into the debouncer must be of a sufficient duration to produce a pulse output to differentiate between noise type pulses and fabric defect pulses.
The signal from debouncer 50 is transmitted to the dual monostable integrated circuit 54. The input received by integrated circuit 54 is a negative going pulse. The input at 56 is a negative trigger input such that when a pulse makes a high to low logic level transition the circuit is triggered and a pulse is produced at output 58. The output of the integrated circuit at 58 is fed by conductor 60 to a four-bit binary up-down counter 62 which counts down one pulse for every pulse that is fed into it. The counter 62 can be preset for registering a predetermined number of counts by the use of digital switches 64. Normally the counter 62 would be set for three pulses whereby this counter permits three defect signals to be produced at the sensing head before more than one defect is considered to exist. The counter 62 compensates for the fact that a single defect, as it rotates and moves in an axial direction past the head 12, may pass the head three times before its axial movement takes it beyond the sensing range of the head. The switches 64 permit the counter to be adjusted in accord with the rate of rotation of the fabric and the rate of axial advancement thereof. Counter 62 is a down counter wherein if it is set for three, three pulses will count down to zero. Upon counter 62 reaching zero terminal 66 of circuit 54 will be triggered producing a pulse output at 68, and it goes to the Darlington transistor drive stage 70 producing a pulse at 72 which is connected to a totalizer defects counter 74.
When terminal 66 is energized terminal 76 of monostable integrated circuit 78 is simultaneously energized. When the carry output of 62 is low 78 is triggered and a positive plus is produced at terminal 80 energizes conductor 82 which is connected to the two input nor gate 84 which is wired in conjunction with the triple input nor gate 86 to produce a latch circuit. The pulse sets the latch circuit and terminal 88 will go to high state and terminal 90 will go to a low state.
Under normal conditions wherein no defects have been detected, the timer circuit which includes 2 input nor gates 92 and 94 and 14-bit binary counter 96 will be inactive and not running. The timer circuit is adjustable to have a time cycle between three and twenty minutes, and this adjustment is accomplished by potentiometer 98. Gates 92 and 94 form an oscillator circuit producing a square wave output at 100. Terminal 102 of counter 96 is normally high which means that counter 96 is reset and ignores the input pulses from gate 94 because the reset overrides the clock input to counter 96.
The dual JK counters 104 and 106 constitute counting apparatus for determining the number of defects acceptable in the time frame. In the disclosed circuit three defects are permitted within the time frame, and it will be appreciated to those skilled in the art that a greater number of defects can be achieved by utilizing additional counters, or by utilizing an up-down counter similar to counter 62 employing setable switches to produce a programable counter. When the latch 84-86 is set the reset conductors on counters 96, 104 and 106 go to a low state, the counters are zeroed, and will accept the clock input, and counter 96 will begin to count up from zero. Counter 96 will count up until it reaches a count of 8192. Upon this count being reached terminal 108 will go high which resets the latch 84-86. Thus, when the timer circuit times out, the time interval will have expired and the latch 84-86 resets the timer apparatus back to its dormant stage. When the counter 96 is counting up the pulses counters 104 and 106 will accept the clock pulses so that when an additional defect is sensed counter 104 will count 1 and on the third count 106 goes to a 1. Until the first defect is sensed counters 104 and 106 are disabled, but when the first defect is sensed and counter 96 is started these counters are enabled so that 104 can accept the second defect count. Upon a third defect pulse being counted while counter 96 is in the process of counting, terminal 110 goes high and in 106 the output terminal 112 goes high which means that three defects have been counted. A latch formed by a pair of triple input nor gates 114 and 116 is set. The transistor pair 118 is turned off which actuates a relay 120 to shut the fabric producing machine off. The output at 122 goes high which produces a positive trigger at 112 at 78 and this produces a pulse at 124. The pulse at 124 goes to transistors 126 and 128 to produce a repetitive defect count at counter 130.
The circuit may include a large hole detector generally indicated at 132, this function being optional to the circuit. The large hole detector receives a signal from the automatic background control circuit which is, of course, proportional to the amount of reflected light. This circuit employs the voltage comparator 132. This circuit measures the duration of a sudden drop in the light level, and this low level, if occurring for a predetermined duration will actuate the nor gate latch 114-122 to stop the fabric apparatus producing.
A power-on reset circuit is generally indicated at 134 in FIG. 7 and is used to eliminate extraneous defect counts. Two input Nand Schmitt triggers 136 are utilized in conjunction with capacitor 138 which is normally discharged at power on and conductor 140 is high and conductor 142 is low which resets the circuit. As the power comes up, the voltage in capacitor 138 slowly charges and when the voltage reaches the threshold voltage of the Nand gate input then the output goes to a low state, 140 goes low and 142 goes high and this means that the resets are removed. The reset switch input 144 is a manual switch which is wired across the capacitor 138 to short the ground to reset the circuit. The capacitor recharges to produce the same condition as a power-on when the switch is released.
In order to provide optimum sensing accuracy of defects in the textile the openings of the passages 18 as defined with the intersection of the face 16 may be partially masked to restrict the "viewing" area of the head 12. Such masking can be accomplished by affixing opaque adhesive strips 146 to the face 16 as shown in dotted lines in FIG. 5 wherein the edges of the strips partially cover portions of the passage openings with the result that the head 12 senses a narrow "slot" on the fabric as represented by the lines 148, FIG. 6, the viewing slot being defined by the area between the lines 148. Thus, the viewing slot is of a continuous configuration, and even very small fabric defects will affect the reflection of the fabric and produce a defect signal.
FIG. 9 illustrates a modification in the circuit which automatically permits the counter 62 to reset in order to insure that a defect signal actually represents a defect and is counted as one defect. The circuit modification shown in FIG. 9 utilizes identical reference numerals to those previously used for the same components, and in the utilization of this modification the large hole detector circuit 132 is eliminated. Thus, the background control amplifier 34 does not have a circuit directly controlling the machine termination control relay 120, as is the case with the above described circuit. The modified circuit is described below:
The output of the integrated circuit 54 at 58 is fed via conductor 60 to the input of a 2-input nor gate 158, which forms a latch circuit with gate 157. Gates 157, 158, together with gates 150, 151 and counter 154, form a timer circuit, the function of which is to time-out the time interval during which counter 62 will accept additional input pulses. A pulse on conductor 60 sets the latch circuit 157-158 (Output 159 goes to a high logic level and output 160 goes to a low logic level). When output 160 goes low, it removes the reset at 155 from counter 154. This allows counter 154 to accept input pulses at 153 from the square wave oscillator circuit which consists of gates 150, 151 and associated circuitry. Counter 154 is a 14-bit binary counter which will count the pulses at 153 until it reaches a count of 8,192. Upon this count being reached, terminal 156 will go high, which resets latch 157-158. Counter 154 is then reset again (160 and 155 go high), and terminal 159 goes low. When terminal 159 goes low, input 76 of monostable integrated circuit 78 also goes low which triggers 78 producing a negative-going pulse at 161 and at the input of nand gate 162. This produces a positive pulse at 163 which presets counter 62, returning counter 62 to its initial state.
Also, when counter 62 reaches zero, the input of a two-input norgate at 165 goes to a low logic level. The other input of this gate at 167 is connected to the 157-158 latch circuit at 160. When the timer is running, terminal 160 is low. Thus, the output of the nor gate at 166 will be high only when the timer circuit is running and counter 62 is in the zero state. Since 166 is connected to the reset input of counter 62, a high level on this line will reset the counter and hold it in this state, effectively disabling it, until the timer latch 157-158 is reset, i.e., the timing interval passes. This feature prevents counter 62 from accumulating additional pulse counts after the preset number set by switches 64 has been counted during the predetermined time interval. This allows the defect to clear the sensing range of the head without causing additional defect counts or a residual count to remain in the counter 62. Note that if the preset number of pulse counts set by switches 64 is not reached in the predetermined time interval, which is set by the oscillator circuit 150-151 and potentiometer 152, then counter 62 will be preset and returned to its initial state. This feature also prevents a residual count from remaining in counter 62, due to random noise pulses which may be picked up by the circuit or sensing head.
From the above description it will be appreciated that the defect detection system of the invention automatically compensates for the reflectance of the fabric being inspected, filters out signals received from the sensing head to minimize the likelihood of false readings, and permits repetitive defect signals to be analyzed wherein a plurality of signals can be recognized as constituting a single defect in an apparatus wherein the fabric movement will cause the defect to be translated past the sensing head several times. The sensing of a defect initiates an adjustable timing circuit which, within the desired time frame, will not stop the fabric producing machine until a predetermined number of bonafide defects occur within the desired time frame. Thus, the quality of the fabric product can be accurately regulated and the highest acceptable production achieved. The invention permits a predetermined number of defects to exist within a given yardage of material, and as missed stitches in knitting machines occasionally occur due to no equipment malfunction or breakage fabric manufacturing apparatus utilizing the system of the invention will not be needlessly shut down and high production rates can be automatically maintained, and yet high quality products assured.
The integrated circuits illustrated are commercially available, and in the following schedule the components are identified by reference numeral, manufacturer and part number.
______________________________________Reference Manufacturer Part No.______________________________________86, 114, 111, 157 RCA CD4025B28, 132 National Semiconductor LM33930, 32 34 National Semiconductor LM324104, 106 RCA CD4027B62 RCA CD4516B92, 94, 84 RCA CD4001B150, 151, 158 RCA CD4001B136, 52 RCA CD4093B154 RCA CD4020B78 RCA CD4098B96 RCA CD4020B50 Motorola MC1449054 RCA CD4098B______________________________________
The reference TP indicates test points.
It is appreciated that various modifications to the inventive concepts may be apparent to those skilled in the art without departing from the spirit and scope of the invention.
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The invention pertains to a defect detection system for inspecting fabric wherein fabric is scanned by electronic light-sensing apparatus for inconsistencies in light reflecting capability and defects produce electronic signals which are counted, and preferably, are automatically counted with respect to a predetermined time interval wherein fabric manufacturing apparatus may be automatically monitored to maintain a predetermined quality of product. Preferably, infrared frequencies are utilized for defect sensing purposes and electronic signal retention counting and timing apparatus automatically terminates fabric production if defect occurence exceeds a predetermined frequency in a given time interval.
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RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Application No. 60/445,689, filed on Feb. 6, 2003, U.S. Provisional Application No. 60/445,703, filed on Feb. 6, 2003, U.S. Provisional Application No. 60/446,045, filed on Feb. 6, 2003, U.S. Provisional Application No. 60/445,704, filed on Feb. 6, 2003 and U.S. Provisional Application No. 60/474,063, filed on May 29, 2003, Docket No. RPI-812, entitled “Parental Suppression via Polymerase-based Protocols for the Introduction of Deletions and Insertions.” The entire teachings of the above applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] In recent years a number of methods have come into common use that allow the generation of site directed mutants without subcloning based on polymerase activity. This technology is mature enough to allow the sale of a number of mutagenesis kits that are capable of producing point mutants and in some case insertion and deletion mutants (‘indels’).
[0003] An important class of polymerase-based mutagenesis methods use two complementary or partially complementary primers together with a thermostable polymerase to produce linearly amplified, double stranded linear DNA. The amplification is linear because primers binding to linear products face the wrong way (3′ out) to serve as primers for elongation. Although these methods are powerful, they contain flaws that limit their application and require expensive and delicate ‘ultracompetent’ cells for transformation because the products are linear.
[0004] A second class of mutagenesis methods use a T4 polymerase and a T4 ligase to make a single mutant copy which forms part of a hybrid circular duplex with the parental template from which it was copied. A second forward selection primer is included allowing partial suppression of parentals based on repair of an antibiotic resistance gene or suppression of a restriction site. The production of circular duplex DNA is highly desirable, but the hybrid nature of the duplex DNA limits the selection to 50% unless additional rounds plasmid preparation and transformation are included. This is so cumbersome that it is generally easier to sequence extra colonies. In addition, the single cycle limits the production of mutant DNA.
[0005] However, a need exists to further improve the efficiency of these methods.
SUMMARY OF THE INVENTION
[0006] INSULT, a novel method for the creation of insertions, deletions, and point mutations without subcloning, requires only one new primer per mutant, and produces circular plasmids, obviating the need for special ‘ultracompetent’ cells. The method includes cycles of linear amplification with a thermophilic polymerase, and nick repair after each cycle with a thermophilic ligase. After production of multiple single stranded copies of circular mutation bearing plasmid DNA, addition of a ‘generic’ primer followed by one or more polymerase reaction cycles generates double stranded circular DNA bearing the desired mutation.
[0007] The present inventions relate to a set of methods which allow the production of site directed mutants via a novel polymerase based strategy which combines the strengths of both of the older methods. The results are high yields of mutant DNA, closed circular double stranded products which obviate the need for specialized ‘ultracompetent’ cells, and protocols which require only one new primer per mutant.
[0008] The invention relates to kits and methods for site-specific in vitro mutagenesis or combinatorial mutagenesis comprising:
(a) cloning a parental polynucleotide (such as polynucleotide comprising a coding sequence or gene) into a vector comprising a cloning site, thereby obtaining a cloned product; (b) denaturing the cloned product, thereby obtaining a single-stranded polynucleotide template; (c) hybridizing at least one mutagenized oligonucleotide primer to the single-stranded polynucleotide template, thereby obtaining a first heteroduplex; ( d) extending the first heteroduplex with a polymerase, thereby obtaining an extended product; (e) reacting the extended product with a ligase, thereby obtaining ligated product; (f) denaturing the ligated product, thereby obtaining a closed single stranded mutated polynucleotide; (g) optionally repeating steps (c)-(f) (e.g., via thermal cycling); (h) hybridizing the single stranded mutated polynucleotides with a second oligonucleotide primer thereby obtaining second hybridized complexes; (i) copying the second hybridized complex and ligating the double stranded product thereof, thereby obtaining a circular double stranded mutated polynucleotide; and (j) transforming the double-stranded mutated polynucleotide into a bacterial host, thereby obtaining transformants.
[0019] In one embodiment, the products can be subjected to optional PCR amplification, or DNA synthesis, such as about four or more cycles, to further increase the number of mutant products.
[0020] In another embodiment the invention provides for a kit for use in the methods described herein comprising:
(a) a vector comprising a cloning site; (b) a generic oligonucleotide primer; (c) a polymerase; (d) a ligase; (e) instructions for carrying out the method.
[0026] The invention also provides for primers and libraries of primers (e.g., two or more primers) for use in the claimed methods and methods of using mutagenized primers in the described methods.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
[0028] FIG. 1 outlines the basic strategy used in INSULT, showing formation of multiple copies of closed mutant single stranded DNA in the first stage and binding of the generic primer to start the second stage. A single cycle of polymerase activity produces mutant closed circular homoduplex DNA; optional additional cycles PCR amplify the mutant product and linearly amplify one strand of parental DNA.
[0029] FIG. 2 is an agarose gel showing raw products of INSULT mutagenesis of small heat shock protein genes in two vectors. The intense single high molecular weight product in lane 7 in the transformant mutant (lower band is primers); lane 5 is similar except for the presence of weak artifact bands. Lane 2 contains an artifact at approximately equal strength to the product due to imperfect ligation. All these attempts were successful in producing the desired mutants without ultracompetent cells.
DETAILED DESCRIPTION OF THE INVENTION
[0030] INSULT, a novel method for the creation of insertions, deletions, and point mutations without subcloning, requires only one new primer per mutant, and produces circular plasmids, obviating the need for special ‘ultracompetent’ cells. The method includes cycles of linear amplification with a thermophilic polymerase, and nick repair after each cycle with a thermophilic ligase. After production of multiple single stranded copies of circular mutation bearing plasmid DNA, addition of a ‘generic’ primer followed by one or more polymerase reaction cycles generates double stranded circular DNA bearing the desired mutation.
[0031] The basic strategy used in INSULT is outlined in FIG. 1 . A single primer bearing a mutation is annealed to one strand of a denatured template consisting of double stranded closed circular plasmid carrying the gene (or other sequence) to be mutagenized. A polymerase, such as T4 or, preferably, thermophilic polymerase and thermophilic ligase (such as, Turbo pfu polymerase and Taq ligase), are added and the temperature cycled to produce single stranded closed circular copies of the target strand as described in the methods section. Use of a single primer produces linear amplification of the mutant strands. When T4 polymerase is employed, one preferably adds enzyme prior to or during each cycle to maximize activity. Thermophilic ligases can often be used without subsequently refreshing the reaction medium.
[0032] In one embodiment, the parental strand is destroyed in the reaction medium or selected against after transformation, for example, by using a selection primer, such as those provided with commercial kits, such as the Clontech Transformer Kit. Alternatively, the method is carried out in the absence of an oligonucleotide primer that repairs or inactivates a selection sequence.
[0033] The mutagenized oligonucleotide primer is capable of hybridizing to the polynucleotide sequence to be mutated and introduce one or more mutations. The primer can insert, delete or substitute/change one or more nucleotides (such as three or more nucleotides) or one or more codons (such as two, five or more codons), for example. Multiple primers (e.g., about 5, 10 or 20 or more) can be used that bind to the same, different, or overlapping or non-overlapping sequences of the parental polynucleotide. The preparation of mutagenizing primers is generally known in the art.
[0034] After production of a suitable number (e.g., preferably between about 10-20) of single stranded mutant copies, a ‘generic’ primer is introduced. This primer should not overlap the mutation, and it is desirable that no part of it be complementary to the mutagenizing primer. If many mutations to genes carried in a vector are contemplated, the generic primer can be made to a position in the vector outside the cloning site. If many mutations are to be made to a gene in different vectors, reverse or forward primers used for copying the gene, or internal sequencing primers which don't overlap the mutation primer, are suitable as long as the generic primer and the mutation primer anneal to opposite strands of the template.
[0035] In one embodiment, the mutagenized oligonucleotide primer further comprises a unique sequence (e.g. at least about 4 nucleotides) which hybridizes to the second oligonucleotide, or generic, primer, thereby introducing a simultaneous selection step in the DNA synthesis step.
[0036] Further adding a blocking oligonucleotide that hybridizes to the parental polynucleotide at or proximal to the sequences the mutagenized oligonucleotide primer hybridizes can additionally provide a negative selection for the parental polynucleotide.
[0037] One cycle of denaturation, annealing, and polymerase activity produces closed circular duplexes of the mutant and parentals; with the mutant DNA in great excess. Additional cycles pcr amplify the mutant DNA and linearly amplify one strand of the parental DNA. This leads to a huge excess of duplex mutant DNA, but many cycles of per could cause the accumulation of copy errors in the pool of mutants even with a high fidelity polymerase.
[0038] It is sometimes convenient to run the first stage overnight, and to finish the procedure with the short second stage (e.g. about 1-5 cycles) the next morning. This allow transformation and plating on selective media on the second day.
[0039] The process can be practiced conventiently with currently available vectors and thermophilic enzymes. Currently available kits, such as the Promega and Clontech mu genesis kits, can be adapted for use in the procedure, but the enzymes used in these kits are not thermostable. This limits them to a single thermal cycle per enzyme addition, which is not optimal. The vectors used can comprise an insertion site for introducing the parental polynucleotide. The vector can also further comprise a replication of origin, such as that of a filamentous bacteriophage, for example. The replication of origin is preferably an f1 replication origin.
[0040] Initial experiments were designed to produce point mutants in the αA-crystalline pACYC184T7 system. The single mutation primers are shown in FIG. 2 ; the generic primers used in these experiments are simply the reverse primers that were originally used to copy the gene for introduction into the plasmid, and overlap the gene/plasmid junction. Any site separated from the mutation primer could have been used, although regions with moderate GC content are most efficient.
[0041] Transformation into BL21 cells with 1 uL of the reaction mixture produced about forty colonies on six plates, two for each mutant. As shown in table 1, the mutation frequency for the initial experiments was approximately 80%, and all three mutants were obtained on the first trial.
[0042] Production of insertion and deletion mutants was investigated using the same system (aA-crystallin pACYC184T7) with primers as indicated in Table 1. Results from these trials are summarized in Table 1. Insertions and deletions were obtained on the first attempt.
[0043] The eNOS pCWori+ system of approximately 9.5 kB represents a significant challenge for mutagenesis because of the presence of GC rich regions and recurring short motifs. Primers designed to insert a stop codon in the eNOS gene failed to produce any mutant colonies in several attempts with Stratagene QCM procedure or with our improved version using separate single primer linear amplification throughout, probably because of runaway PCR artifact.
[0044] Transformation of the same cell line (Stratagene XL10-Gold Ultracompetent cells) with the products of the mutagenesis procedure described here under the same conditions produced approximately 150 colonies per plate. As indicated in Table I, all of the colonies sampled were mutants, indicating that the mutation frequency is at least comparable to that obtained with the pACYC184T7 system. Direct comparison of these results suggests that for this mutant the new procedure is at least 1000 times more effective.
[0045] Selection Primer System. Several other selection systems are in use, including repair of antibiotic resistance genes and removal of restriction sites, which are features of the Promega and Clontech mutagenesis kits. The Promega kits was used to demonstrate the ability of the new procedure to use the selection protocol. The proprietary plasmid and repair primer generated colonies with the appropriate antibiotic resistance in the first attempt when transformed into Promega's competent cell line.
[0046] These results are significant because the new protocol transforms both the Promega and Clontech selection methods from a 50% theoretical mutation frequency to a 100% theoretical mutation frequency.
[0047] The production of mutant genes and their products without subcloning has been an important technical advance. Limitations of existing techniques flow naturally from flaws in strategy. QCM is well known to produce primer dimer in some situations, limiting its application in indel production. In addition, all QCM like procedures have the potential to degrade the mutant DNA they produce as the procedure is carried out. Although the mutant strands are never templates for the production of new mutant DNA from the mutagenic primers, the forward and reverse strands can prime each other for extension unless blocked by ‘wrong way’ (3′ out) primer binding. Where extension occurs, each strand is blunt ended, preventing the formation of circular DNA, and the gene is disrupted by the addition of a second copy of the primer sequence. To make matters worse, the duplexes destroyed by this process are now templates for runaway per, limiting the number of cycles of amplification that can be carried out. In favorable cases a high frequency of mutation can still be obtained, but the procedure still produces single stranded DNA requiring ultracompetent cells for transformation.
[0048] Clontech and Promega type strategies are limited by production of only a single copy of mutant DNA per parental, and by the production of hybrid duplexes which limits the selection power of antibiotic or restriction enzyme resistance. Production of high levels of mutant DNA is relatively easy by using thermostable enzymes that allow multiple copying steps. Introduction of a completely uncomplimentary, generic reverse primer makes INSULT qualitatively different from previous procedures, because the mutant copies produced are closed circular AND homoduplex. This is only possible because the multiple copies produced in stage 1 are in closed circular form; linear copies produced without ligase activity cannot be templates for synthesis of a reverse strand without introduction of primers to sites adjacent to the mutagenic primer, and this produces blunt ended linear duplexes.
[0049] Numerous variants of INSULT are feasible. Running a single cycle second stage decreases the amount of mutant DNA with the compensating advantage of introducing fewer copy errors. There are several options available for parental suppression. These include DPN1 digestion of methylated template as introduced by Strategene. Clontech and Promega selection strategies use a second forward ‘selection’ primer to repair an antibiotic resistance site or suppress a restriction site, and many other schemes are possible e.g., introduction of a mutation preventing induction of an inhibitory gene. These schemes are of real but limited utility in existing protocols because duplex DNA is a hybrid with one mutant and one parental strand, limiting selection efficiency to 50% with one transformation. Because INSULT produces homoduplexes, these selection schemes have a theoretical efficiency of 100% when applied within the INSULT context. This is true even in the limiting case when both the first and second stage are reduced to a single cycle, which would allow the use of T4 or other thermosensitive polymerase and ligase combinations. We believe that the T4 system is less desirable because of the lack of amplification of mutant DNA, but in view of the potential for total parental suppression this could be compensated for by increasing the level of template DNA.
[0050] The inherent ligase component of INSULT provides great potential for parallel introduction of multiple mutations. Multiple mutagenic primers would be extended by the polymerase to produce sections of DNA aligned along the circular template; the nicks separating the ends would be repaired by the ligase, generating multiple mutations in a single procedure. Limitations on this capability are imposed primarily by the need to not have the primers overlap, and in many cases closely spaced mutations could be carried on a single primer. Typically, the mutagenizing primers for point mutations are between about 15 and 35 basepairs (often 18-30 basepairs) in length. Mutations to two codons separate by less than half the primer length can most easily be accommodated by changing both codons in a single mutation. Mutagenizing primer design is generally known in the art. Combinatorial numbers of mutants and ‘limited chimera’ can in principle be constructed with a limited number of primers by applying the multiple mutation approach with mixtures of mutagenic primers. (The chimera produced are limited in scope by the size of the individual primers used). For example, n sets consisting of m mutagenic primers each, binding to n different sites within a gene, would generate m n mutants from m n primers when run together in the first stage. A single generic primer would suffice for the second stage. Use of a combinatorial mutagenic primer (a primer set in which all or many possible combinations of bases in a short stretch are present) would produce a combinatorial mixture of mutants concentrated in a single site. Since in all cases the mutants are produced without subcloning and transform directly into cell lines capable of expression, the system has great potential for selection-based applications.
[0051] A primary advantage of INSULT is the ability of the relatively high levels of circular duplex mutant DNA to transform expression competent cells directly. In most cases this represents a greater economy than the need for only one primer per mutation. More importantly, it removes the need for a second cycle of transformation to produce mutant proteins, which in most cases is the object of the exercise. This streamlining of the procedure greatly reduces the time and effort involved. In addition to saving human time, it moves the entire process into a form amenable to 96 well plates and robotics until the point of scale up from colony selection to protein production. In most cases expensive ‘Ultracompetent’ cells are unnecessary. On the other hand, the use of such cells in the INSULT process can produce very large numbers of mutants compared to other methods and allows the rapid production of mutants.
[0052] One skilled in the art will appreciate the many advantages that the method of the invention provides. For example, the improved site-directed mutagenesis methods of the invention are useful in protein and enzyme engineering technologies (to impart desirable properties on proteins, enzymes, polynucleotides, etc.) for the production of drugs, diagnostics, research proteins and enzymes, agrochemicals, plant proteins, industrial proteins and enzymes such as detergent enzymes, enzymes useful for neutralizing contaminants, and enzymes suitable for improved or novel biosynthesis of compounds in industry, biotechnology, and medicine. Likewise the methods of the invention are useful in protein engineering technologies for the production of proteins useful in the food and life sciences industries such as primary and secondary metabolites useful in the production of antibiotics, proteins and enzymes for the food industry (bread, beer), and combinatorial arrays of proteins for use in generating multiple epitopes for vaccine production. The invention can also be used to manufacture novel polynucleotides, including DNAs and RNAs, such as RNA inhibitors. In yet other embodiments, the inventions can be used to manufacture protein tags, such as N-terminal addressing, affinity tags, labeling sites, etc. The invention can be used in cell biology discovery and understanding protein-protein interactions. Fusion proteins for purification, targeting, labeling can be manufactured using the methods of the invention. For example, vectors with a GFP gene adjacent to a cloning site would allow easy conversion of a vector for expression of a target gene, e.g. via a linker.
EXAMPLES
[0053] Methods
[0054] Polymerase and ligase reactions were carried out simultaneously in the same vessel. The reaction mixture consisted of 5 ul of 10× Reaction buffer, 10 ng of template DNA, 125 ng of phosphorylated mutagenesis primer, 5 ul 10 mM NAD+ (ligase cofactor), 1 ul 20 mM dNTP mix, 1 ul Pfu Turbo, 1 ul Taq DNA ligase, and dH20 addded to make the final reaction mixture 50 uL.
[0055] The thermocycler program consisted of two stages. In the first, the template was denatured at 94C for 2′, followed by annealing at 60C for 50 sec and extension for 10 minutes at 68C; on completion of extension around the plasmid the ligase closed the nicked product. Subsequent cycles (1-5) were identical except that the 94C step was shortened to 50 sec.
[0056] After holding at 4C, 2 ul 100 ng/ul phosphorylated universal primer was added to the reaction mixture in preparation for step 2 . After denaturation at 94C for 2 minutes, the primers were annealed for 50 sec at 60C and extended at 68C, followed by nick repair. Up to four additional cycles followed as in the first stage.
[0057] 50 uL of competent BL21DE3 cells were transformed with 1 uL reaction mixture, and the resulting transformed cells were plated on LB antimycin plates for selection of colonies. A representative fraction of antibiotic resistant colonies were selected and sequenced to confirm the production of mutants.
[0058] Transformation of the same cell line (Stratagene XL10-Gold Ultracompetent cells) with the products of the mutagenesis procedure described here under the same conditions produced approximately 150 colonies per plate. As indicated in Table I, all of the colonies sampled were mutants, indicating that the mutation frequency is at least comparable to that obtained with the pACYC184T7 system. Direct comparison of these results suggests that for this mutant the new procedure is at least 1000 times more effective.
TABLE 1 Sequencing Clone name Primer Sequence Results Alpha A F: CGC GAG TTC CAC GGC CGC TAC CGC CTG CCT TCC (SEQ ID NO. 1) 2/3 Crystallin- R: CC CCT CAA GAC CCG TTT AGA GGC CCC (SEQ ID NO. 2) R116G Alpha A F: GGA GAT ATA CAT ATG GGC ATC GCC ATT CAG CAC CCC TGG (SEQ ID NO. 3) 2/3 Crystallin- R: CC CCT CAA GAC CCG TTT AGA GGC CCC (SEQ ID NO. 4) D2G Alpha A F: GAG GTC CGA TCC GAC CGG AGC AAG TTT GTC ATC TTC CTG G (SEQ ID NO. 5) 3/3 Crystallin- R: CC CCT CAA GAC CCG TTT AGA GGC CCC (SEQ ID NO. 6) D69S Alpha A F: GCC CAG CTC TGC GCT GTG GAA G CT CGA GCA CCA CCA CCA CC 1/1 Crystallin- (SEQ ID NO. 7) ALWKG R: CCC CCT CAA GAC CCG TTT AGA GGC CCC (SEQ ID NO. 8) Chimera F: CAG CTC TGC GCC TC GTC CCT CGA GC (SEQ ID NO. 9) 2/2 correction R: CC CCT CAA GAC CCG TTT AGA GGC CCC Bold = substitution Highlight = insertion
Forward (mutagenic) and reverse (generic) primers for initial trails with INSULT mutagenesis. Sequencing results indicate the number of correct mutant sequences and total trials.
[0059] FIG. 2 shows an agarose gel of the raw products of the INSULT process on three different small heat shock protein/vector combinations. Unlike any of the competing procedures, the transforming product is visible in all cases as a major band (usually the only major band apart from the primers). The production of large amounts of high quality (i.e., closed circular homoduplex) mutant DNA is a key to the success of the method.
[0060] While this invention has been particularly shown and described with references to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
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The invention relates to primers, libraries of primer, kits and methods for site-specific in vitro mutagenesis comprising: (a) cloning a parental polynucleotide into a vector comprising a cloning site, thereby obtaining a cloned product; (b) denaturing the cloned product, thereby obtaining a single-stranded polynucleotide template; (c) hybridizing at least one mutagenized oligonucleotide primer to the single-stranded polynucleotide template, thereby obtaining a first heteroduplex; (d) subjecting the first heteroduplex to linear amplification, thereby obtaining amplified products; (e) reacting the amplified products with a ligase, thereby obtaining ligated products; (f) denaturing the ligated products, thereby obtaining single stranded mutated polynucleotides; (g) hybridizing the single stranded mutated polynucleotides with a second oligonucleotide primer thereby obtaining second hybridized complexes; (h) copying the second hybridized complex and ligating the double stranded product thereof; thereby obtaining a circular double stranded mutated polynucleotide; (i) transforming the double-stranded mutated polynucleotide into a bacterial host, thereby obtaining transformants.
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CROSS-RELATED APPLICATION
This application is a Non-Provisional Application claiming the benefits of U.S. Provisional Patent Application Ser. No. 61/939,775 filed Feb. 14, 2014, the entirety of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Technical Field
The invention relates generally to startup burners and specifically to startup burners used in chemical recovery boilers in the pulp and paper industry.
2. Related Art
Chemical recovery boilers isolate useful compounds from manufacturing byproducts. In the pulp and paper industry, pulp mills typically use a manufacturing process in which wood chips or other lignocellulosic biomass are treated with chemical liquor comprising cooking chemicals. The wood chips or other lignocellulosic materials are then cooked in a digester at predetermined temperature and pressure to form a slurry comprising spent liquor and a rough pulp with inconsistent particle size. After cooking, equipment washes the spent chemical liquor from the rough pulp. The spent liquor is commonly known as “black liquor” and comprises organic and inorganic chemicals left over from the cooking process. The pulp is generally sent to other equipment for further refinement. The black liquor is eventually pumped to a chemical recovery boiler and processed to recover the cooking chemicals. Without recovering and reusing the cooking chemicals from the black liquor, the cost of industrial paper-making processes would be prohibitive.
Chemical recovery boilers generally evaporate excess moisture from black liquor solids, burn organic liquor components, supply heat for steam generation, and recover inorganic compounds—notably sodium sulfide and sodium carbonate. Some of these compounds can be re-causticized and used elsewhere in the manufacturing process.
In the recovery process, the black liquor is typically concentrated into a solution containing a solids concentration of above sixty percent by mass. Nozzles in the furnace wall then spray black liquor into a furnace. The nozzles are generally located in the bottom quarter of the furnace and may be several meters above the bottom of the furnace. The furnace is a reactor that generally dries and partially pyrolyzes the liquor droplets as they fall toward the bottom of the furnace. The furnace also evaporates, gasifies, oxidizes, and reduces, components within the black liquor to recover the cooking chemicals.
The partially dried and reacted black liquor accumulates in a mound at the bottom of the furnace known as a “char bed”. Nozzles typically permit airflow into the furnace at a low, middle, and upper elevation. The air, together with the lignin, wood extracts, and other organic compounds maintain combustion in the furnace. Inorganic compounds are often reduced in the char bed into a molten smelt. The smelt may accumulate and flow out of the furnace through a smelt spout and into a collection tank. These reactions consume heat. As such, operators generally regulate and redistribute airflow and black liquor input, to promote and maintain combustion for efficient chemical recovery.
In traditional recovery boilers, the furnace is internally lined with a series of densely-arranged, high-pressure coolant-filled tubes. The coolant is commonly water and a collective series of tubes is generally known as a “water wall.” To regulate temperature efficiently, the water wall tends to cover a large internal surface area. In some existing chemical recovery boilers, three inch coolant tubes are generally separated by one inch filler bars so as to form a gas-tight barrier enclosing the furnace.
To operate safely and efficiently, the furnace generally operates under negative pressure. A constant inflow of air near the base of the furnace is generally required to maintain combustion and to replace air and other gases that exit the recovery boiler near the top of the furnace. Air generally enters the otherwise gas-tight furnace through openings in the furnace water walls. Such openings include air ports and throats, which are designed to inject pressurized air. Ambient air generally flows through other openings, such as those for smelt spouts, due to the negative pressure in the furnace. For most such openings, the coolant tubes generally bend around the opening in the furnace wall.
Air manifolds or windboxes generally flank the throat and air port openings on the outer wall of the furnace. Large fans ducted to the windboxes can cause air to flow into the furnace through the various throats and air ports in the furnace walls.
Airflow is the primary variable of operation aside from the rate of black liquor input. Large quantities of air are generally forced through the narrow throat and air port openings to maintain combustion. The flow of air through a throat and, diffuser, or swirler is desirable to maintain auxiliary combustion from active startup burners. Unfortunately, conditions within the furnace contribute to the gradual obstruction of air flow as smelt slowly accumulates over the various openings. Over time, accumulations of frozen smelt on and around the coolant tubes can grow to obstruct the openings, thereby reducing an operator's ability to regulate combustion. Recovery boilers may need to be deactivated when smelt accumulations significantly interfere operation. This extensive maintenance period results in loss of production.
Temperature is another variable of operation. Startup burners help regulate internal furnace temperature. Startup burners are auxiliary burners that commonly fire natural gas, propane, and/or fuel oil, and are generally used to initiate combustion within the furnace after a period of dormancy. Once the startup burners increase furnace temperature to an established minimum, liquor firing can commence. Liquor firing is then increased until the liquor itself sustains combustion. The startup burners are then generally deactivated. Startup burns have also been used to provide supplementary heat to the furnace when liquor flow is interrupted or insufficient to meet boiler demand.
When inactive, the startup burner generally rests in the windbox within a burner housing adjacent to the throat opening. Radiant heat from the furnace can damage inactive startup burners. Moreover, splashes of black liquor through the throat openings can cause smelt fouling directly on the startup burner, particularly on the firing end of the startup burner, comprising, for example, the fuel nozzles, swirler, igniter assembly, and flame detection equipment. Smelt fouling can render the startup burner ineffective, unsafe, and unreliable.
There is a need to increase the intervals between recovery boiler maintenance and to reduce the amount of maintenance time while preserving or improving the operability of the recovery boiler after said maintenance.
SUMMARY OF THE INVENTION
The problems of loss of production caused by deactivating a chemical recovery boiler for the purpose of manually dislodging accumulations of smelt, airflow interference in the chemical recovery boiler, exposing operators to hot air from the furnace and windbox, and startup burner damage due to smelt spattering and radiant heat from the furnace is mitigated by using a system of isolation chambers engaged to the outer wall of a windbox to extract startup burners from windboxes engaged to the outer wall of the furnace of the chemical recovery boiler, such that the isolation chambers are configured to partially isolate the startup burner from the windbox and furnace environment before extraction. In alternative embodiments, the isolation chambers may isolate the extractable startup burner substantially completely from the windbox and furnace environment.
Some conventional startup burners may have a retraction feature whereby the burner can be manually or automatically retracted from an active position. That is, while the firing ends of the startup burners can be retracted from the furnace, the body and firing ends remain in the windbox proximate to the furnace and directly behind the wall openings in the furnace. Retracted firing ends are typically eight to sixteen inches from the furnace. By retracting an inactive conventional startup burner from the furnace, conventional burners have sought to reduce exposure to furnace temperature and smelt fouling. While conventional burners have been somewhat effective in prolonging the useful life of startup burners, conventional burners have significant drawbacks.
Conventional burners preclude startup burner maintenance while the recovery boiler is operational. The potential for smelt splatter renders human intervention unsafe. Hot air in the pressurized windbox and radiant heat from the furnace complicate human intervention. Conventional startup burners generally require constant exposure to moving air to prevent overheating. This tramp air flowing from the windbox through the throats and into the furnace can also provide oxygen to maintain combustion. Operators generally consider the amount of air entering the furnace as a variable when attempting to maintain a desirable combustion rate. To this end, some conventional startup burners are placed within housings having variable position dampers. The housings are likewise placed within the windbox. The variable position dampers can allow operators to affect the amount of air flowing over the startup burner to the boiler. However, the desire to preserve the startup burner from overheating prevents operators from closing variable position dampers completely.
Airflow within the windbox may become dynamic and irregular based partially on the oxygen demands of the furnace. Additionally, the startup burner obstructs the air flow in the housing, thereby facilitating an irregular and unpredictable insertion of air into the recovery boiler.
With regard to retracted startup burners, smelt fouling still occurs due to residual splashing of black liquor droplets through the throats and onto the firing end. The firing end generally includes a diffuser, or swirler, which can be used to direct or shape the flame emanating from the startup burner. The swirler's large surface area relative to the throat can increase the incidence of smelt accumulation on the swirler. Additionally, radiant heat from the furnace can damage the startup burner. The presence of retracted startup burners directly behind the occluded throats can interfere with operator's ability to clear the occlusions and perform necessary maintenance of the burners while the boiler remains operational.
Embodiments of the current disclosure comprise an isolation chamber located behind an extractable startup burner in a windbox. The assembly separates an operator from the pressurized hot air in the windbox and furnace thereby permitting operators to remove inactive startup burners safely while the recovery boiler is operational. Once the startup burner is removed, operators may use a rod, a cleaning brush mounted on a pole, or other suitable cleaning means to clean the throats manually. If the width of the isolation chamber is sufficiently wide, operators may clean multiple openings in the furnace wall through a single isolation chamber. Additionally, the exemplary assembly allows operators to replace or repair startup burners, as needed for optimal boiler operation, between scheduled outages.
Further, use of an extractable startup burner with an isolation chamber may eliminate or reduce the need for burner-cooling air. In conventional burners, variable position dampers in burner housings remain partially opened when the startup burner is inactive. The variable position dampers allow air from the windbox to cool the inactive startup burner and to counter effects of radiant heat. Throats in the furnace wall are generally uncovered when a startup burner is not in use, so tramp air in the burner housing used to cool the inactive startup burner may also flow into the furnace uncontrollably. This undesirable influx of air into the furnace can complicate an operator's ability to control and maintain optimal combustion conditions. Additionally, the presence of a conventional retracted startup burner in the windbox can interfere with desirable airflow.
Use of an extractable startup burner and isolation chamber as set forth in the present disclosure may allow operators to close fully variable position dampers in the burner housing and reduce or prevent tramp air from entering the furnace, thus improving air distribution control. Accordingly, it is an object of the present disclosure to improve air distribution control in a chemical recovery boiler—particularly in the windbox and through openings in the furnace wall.
A recovery boiler startup burner assembly has been conceived comprising: a furnace having areas defining openings in a furnace wall, a windbox exteriorly engaging the furnace wall, wherein the windbox is configured to contain pressurized combustion air, an isolation chamber exteriorly engaging a windbox wall, wherein the isolation chamber is aligned with an area defining an opening in the windbox wall and an area defining an opening in the furnace wall, a startup burner disposed within the windbox, the startup burner having a firing end and a supply end, wherein the firing end is aligned with the area defining an opening in the furnace wall and the supply end is aligned with the area defining an opening in the windbox wall, wherein the startup burner is configured to be extracted through the isolation chamber, and wherein the isolation chamber is configured to isolate an extracted portion of the startup burner from the windbox.
The isolation chamber may comprise a multi-door isolation chamber. In another exemplary embodiment, the isolation chamber may comprise a burner guide sleeve having a hinged door at one end and a seal plug at the other end. In still other exemplary embodiments, the isolation chamber may be configured to isolate the startup burner partially from the windbox. In yet other exemplary embodiments, the isolation chamber may be configured to isolate the startup burner from the windbox substantially completely.
In still other exemplary embodiments, the assembly for a recovery boiler may further comprise a cooling carriage comprising a structural brace having a first end and a second end, the second end being mounted to an outer wall of the recovery boiler and the first end being engaged to a first end of a main support beam, a second end of the main support beam being engaged to the outer wall of the recovery boiler, the cooling carriage may further comprise a carrier assembly linkage having at least one first end and at least one second end having at least one roller rotatably mounted to the at least one second end of the carrier assembly linkage.
The cooling carriage may further comprise a local temperature display. The local temperature display may be a contact-type temperature display, such as a resistance temperature detector (“RTD”) or a thermocouple detector. In other exemplary embodiments, the local temperature display may be a non-contact type display such as an infrared thermometer or a laser thermometer.
A method has been conceived for extracting a startup burner comprising: deactivating a startup burner, disconnecting wires and hoses from the startup burner and an igniter assembly, withdrawing the startup burner from a throat in a furnace wall, removing the igniter assembly from the startup burner, lowering a support brace to the startup burner, withdrawing the startup burner into an inner space defined by the multi-door isolation chamber, closing at least one inner door of the multi-door isolation chamber to support the startup burner, withdrawing the startup burner through the inner space defined by the multi-door isolation chamber, opening at least one outer door of the multi-door isolation chamber, closing the inner door of the multi-door isolation chamber, and removing the startup burner from the inner space of the multi-door isolation chamber.
A multi-door isolation chamber for use with a recovery boiler windbox has been conceived comprising: a multi-door isolation chamber disposed proximate to a windbox opening defined by an outer wall of a windbox, at least one inner door configured to occlude partially the windbox opening and support a startup burner, and at least one outer door configured to occlude a multi-door isolation chamber opening defined by an outer face of the multi-door isolation chamber.
Another method has been conceived for extracting a startup burner from a recovery boiler comprising: shutting down a startup burner; disconnecting wires and hoses from the startup burner and an igniter assembly; withdrawing the startup burner from a throat in a furnace wall; removing the igniter assembly from the startup burner; lowering a support brace to the startup burner; closing the first inner door of the multi-door isolation chamber to support the support brace and startup burner; withdrawing the support brace with the startup burner through a first inner door of a multi-door isolation chamber into an inner space defined by the multi-door isolation chamber; closing a second inner door of the multi-door isolation chamber to substantially isolate the support brace with the startup burner in the inner space of the multi-door isolation chamber; opening at least one outer door of the multi-door isolation chamber; and removing the startup burner from the inner space of the multi-door isolation chamber.
A method for cleaning smelt accumulations in a recovery boiler during operation has been conceived comprising: shutting down a startup burner, disconnecting wires and hoses from the startup burner and an igniter assembly, withdrawing the startup burner from a throat in a furnace wall, removing the igniter assembly from the startup burner, withdrawing the startup burner into an inner space defined by the multi-door isolation chamber, closing at least one inner door of the multi-door isolation chamber, withdrawing the startup burner through the at least one inner door of a multi-door isolation chamber to substantially isolate the startup burner in an inner space defined by the multi-door isolation chamber, opening at least one outer door of the isolation chamber, removing the startup burner from the isolation chamber, and extending a rod through the multi-door isolation chamber to dislodge smelt accumulations from the throat in the furnace wall.
The method for cleaning smelt accumulations may further comprise extending a carrier assembly linkage of a cooling carrier into a path of the startup burner, placing the startup burner on rollers extending from the carrier assembly linkage, and allowing a hot end of the startup burner to cool on the rollers.
A method has been conceived for replacing an extractable startup burner in a recovery boiler during operation comprising: aligning a support brace with an outer door of an isolation chamber; mounting a startup burner on a support brace, opening at least one outer door of the isolation chamber, inserting a startup burner into an inner space of the isolation chamber, closing the at least one outer door of the isolation chamber to support the startup burner, closing a second outer door of the isolation chamber to substantially isolate the startup burner in the inner space of the isolation chamber; extending the startup burner from the at least one inner door toward a throat in a furnace wall; and connecting wires and hoses to a startup burner and an igniter assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing will be apparent from the following more particular description of exemplary embodiments of the disclosure, as illustrated in the accompanying drawings. The drawings are not necessarily to scale, with emphasis instead being placed upon illustrating the disclosed embodiments.
FIG. 1 is a side-view of an exemplary embodiment of a recovery boiler with windboxes and several multi-door isolation chambers engaged to the sides of the windboxes.
FIG. 2 a is a perspective view of an exemplary embodiment of the multi-door isolation chamber, the windbox, and the path by which the startup burner may be removed from the windbox.
FIG. 2 b is a cross-sectional view of an exemplary embodiment of the multi-door isolation chamber, the windbox, and the path by which the startup burner may be removed from the windbox.
FIG. 3 is a burner end view of an exemplary embodiment of the multi-door isolation chamber, the throat, and the swirler with the outer doors of the multi-door isolation chamber engaged to the front plate of the multi-door isolation chamber via hinges.
FIG. 4 is a top-down view of an exemplary embodiment of the multi-door isolation chamber mounted to the outer wall of the chemical recovery boiler and the startup burner extending through the windbox and into the furnace.
FIG. 5 a is a front view of an exemplary first inner door and second inner door of the multi-door isolation chamber configured to substantially completely isolate a startup burner in the multi-door isolation chamber.
FIG. 5 b a front view of an exemplary embodiment of the first inner door and second inner door of the multi-door isolation chamber that are slidably engaged proximate to the windbox along a track.
FIG. 6 a is a side view of an exemplary cooling carriage affixed to the outer wall of a windbox.
FIG. 6 b is a front view of an exemplary cooling carriage depicting the extended carriage's position relative to the multi-door isolation chamber.
FIG. 7 is a side view of an exemplary burner guide sleeve with a plug and flapper seal.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description of the preferred embodiments is presented only for illustrative and descriptive purposes and is not intended to be exhaustive or to limit the scope and spirit of the invention. The embodiments were selected and described to best explain the principles of the invention and its practical application. One of ordinary skill in the art will recognize that many variations can be made to the invention disclosed in this specification without departing from the scope and spirit of the invention.
Although the drawings represent embodiments of various features and components according to the present disclosure, the drawings are not necessarily to scale and certain features may be exaggerated in order to better illustrate embodiments of the present disclosure, and such exemplifications are not to be construed as limiting the scope of the present disclosure.
The present disclosure describes an isolation chamber that may be used with a startup burner configured to be removed or replaced while the boiler is operating. Natural gas, oil, propane, or other fuel known to those having ordinary skill in the art may fuel the startup burner. Although the startup burner may be used in boilers or process furnaces generally, subsequent exemplary uses will refer to recovery boilers used in the pulp and paper industry.
FIG. 1 depicts an exemplary embodiment of the isolation chamber 106 attached to windboxes 190 of a recovery boiler 107 . The windboxes 190 generally span the sides of the furnace 199 horizontally and may contain throats ( FIG. 2, 240 ), housings ( FIG. 4, 491 ), startup burners ( FIG. 2, 200 ), or other instruments such as air nozzles or probes to record furnace conditions (not depicted). Recovery boilers 107 generally have a primary windbox 190 a , a secondary windbox 190 b , and tertiary windbox 190 c spanning the sides of the furnace 199 . The primary windbox 190 a is generally closest to the ground and the tertiary windbox 190 c is generally furthest from the ground. In certain exemplary embodiments, exemplary isolation chambers 106 may be attached to the primary windbox 190 a and secondary windbox 190 b . In other embodiments, at least one exemplary isolation chamber 106 may be attached to the primary windbox 190 a . In still other embodiments, exemplary isolation chambers 106 may be attached to any one of the primary windbox 190 a , secondary windbox 190 b , or tertiary windbox 190 c . In other exemplary embodiments, at least one exemplary isolation chamber 106 may be attached to each of the primary windbox 190 a , secondary windbox 190 b , and tertiary windbox 190 c.
FIG. 2 a depicts a perspective view of the exemplary multi-door isolation chamber 206 engaged to a mounting plate 218 secured to the outer wall 222 of the windbox 290 . In this exemplary embodiment, the multi-door isolation chamber 206 is generally in the shape of a rectangular prism (i.e. box-shaped); however, on other embodiments, the multi-door isolation chamber 206 may be generally cylindrical, generally in the shape of a geometric prism having greater than three edges, or generally irregularly shaped. A generally irregularly shaped isolation chamber 206 may have a sample cross sectional area at a first position (e.g. a measurement of cross sectional area measured along a first plane) that differs from a sample cross sectional area at a second position (e.g. a measurement of cross sectional area measured along a second plane parallel to the first plane).
The startup burner 200 may comprise an inlet 207 through which natural gas, air, or other fuel enters the startup burner 200 . The inlet 207 is generally located at the supply end of the startup burner. The fuel generally flows along the length of the startup burner 200 and into the furnace 299 . Air enters the furnace through throat 240 , and may flow across swirler 250 . The swirler rotates thereby aiding fuel and air mixing. Operators may monitor the fuel input and amount of air entering the furnace 299 from the windbox 290 to increase furnace temperature and melt or burn away smelt accumulations. During operation, a startup burner 200 may extend through the multi-door isolation chamber 206 and traverse the windbox 290 . Water wall tubes 270 may bend to create an open area, which defines a throat 240 . In other embodiments, the throats 240 may be further defined by a reinforcing element (not depicted) disposed within the opening defined by the water wall tubes 270 . The reinforcing element may generally conform to the hole defined by the bend water wall tubes 270 and may be made from carbon steel or other material configured to withstand furnace heat.
An exemplary startup burner assembly 241 may have an observation port 260 through which operators may view the inside of the windbox 290 , throat 240 , and furnace 299 . An operator may look through the observation port 260 to determine the amount of smelt accumulation around the throat 240 . If smelt has accumulated, an operator may insert a rod (not depicted) through port 251 to dislodge the smelt accumulations while the recovery boiler is operational. In an exemplary method, an operator may insert the rod through the multi-door isolation chamber 206 .
In the exemplary startup burner assembly 241 of FIG. 2 a , the multi-door isolation chamber 206 is configured isolate the startup burner 200 from the furnace 299 and windbox 290 by using outer doors 210 , 216 and inner doors ( FIG. 2 b 220 , 226 ). The outer door comprises a bottom outer door 210 engaging handle 230 b and a top outer door 216 engaging handle 230 c . Handle 230 d engages top inner door 226 , while handle 230 a engages bottom inner door 220 . The outer doors 210 , 216 and inner doors 220 , 226 desirably open inwardly toward the furnace 299 and windbox 290 . In this configuration, pressure generated by the furnace 299 and windbox 290 exerts an outward force on the inner doors 220 , 226 and outer doors 210 , 216 . Inwardly opening doors may reduce the risk of sudden release of hot air and potential smelt splatter if the pivot mechanism 266 fails. If both inner doors 220 , 226 and outer doors 210 , 216 were configured to open outwardly, the pivot mechanisms 266 keeping the inner doors 220 , 226 and outer doors 210 , 216 closed would be more likely to experience prolonged stress due to the windbox-pressure and therefore be more likely to fail spontaneously and expose personnel and nearby equipment to hot, high-pressure air from the windbox 290 . Although the inner doors 220 , 226 and outer doors 210 , 216 desirably open inwardly, other exemplary embodiments may comprise one or more inner doors 220 , 226 and outer doors 210 , 216 opening outwardly away from the windbox 290 and furnace 299 . The bottom inner door 220 and bottom outer door 210 pivot at the bottom of the multi-door isolation chamber 206 in FIG. 2 a . Likewise, the top inner door 226 and top outer door 216 pivot at the top of the multi-door isolation chamber 206 . In other exemplary embodiments, the outer and inner door may comprise two or more doors, one or more of which may pivot on the right side of the isolation chamber 206 , and one or more of which may pivot on the left side of the isolation chamber 206 (see FIG. 5 ). In other exemplary configurations, an odd number of outer doors may be used. In yet other embodiments, an odd number of inner doors may be used. The bottom outer door 210 may have a cut-out portion 213 configured to support the startup burner 200 . The outer door may be a singular outer door. The inner door may be a singular inner door. Nothing in this disclosure limits the combination of aspects of one embodiment with aspects of one or more other embodiments.
FIG. 2 b is a cross sectional view of an exemplary startup burner assembly 241 . The startup burner 200 may be extracted through the windbox 290 and bottom inner door 220 of the multi-door isolation chamber 206 . Operators may then use handle 230 a to close the bottom inner door 220 of the multi-door isolation chamber 206 . In this exemplary embodiment, the bottom inner door 220 may be a plate of carbon steel or other material suitable to withstand the heat and pressure of the windbox 290 and an occasional splatter of black liquor (not pictured) through the throats 240 of the furnace 299 . Bottom inner door 220 may be configured to provide support for the startup burner 200 as the startup burner 200 is extracted from the windbox 290 . The bottom inner door 220 , when closed, may occupy a portion of the opening 221 created in windbox mounting plate 218 . In other exemplary embodiments, the bottom inner door 220 , when closed, may be configured to occupy substantially all of the opening 221 ; in this manner, a portion of the startup burner 200 may be substantially completely isolated in the internal space 225 of the multi-door isolation chamber 206 .
In still other exemplary embodiments, the bottom inner door 220 , when closed, may be configured to occupy half of the opening 221 . In yet other exemplary embodiments, the bottom inner door 220 , when closed, may be configured to occupy a portion of the opening 221 . In this manner, a portion of the startup burner 200 may be partially isolated in the internal space 225 defined by the multi-door isolation chamber 206 .
Thus protected from the furnace environment and so isolated from the windbox 290 , an operator may open the outer door 210 of the multi-door isolation chamber 206 and remove the startup burner 200 from the multi-door isolation chamber 206 with reduced risk of burns due to hot air or molten smelt. In addition to being protected, the operator, by extracting the startup burner 200 , may extend the useful life of the startup burner 200 by removing the startup burner 200 from the recovery boiler completely. By having the startup burner 200 completely removed from the recovery boiler, the operator may maintain, repair, or replace the startup burner 200 while the recovery boiler is operational, while substantially eliminating the risk of injury from the recovery boiler.
The outer doors 210 , 216 and inner doors 220 , 226 desirably open inwardly toward the windbox 290 and furnace 299 . The pressure created by the furnace 299 and moving air within the windbox 290 exerts a force against the closed inner doors 220 , 226 and outer doors 210 , 216 . By opening inwardly, the closed inner doors 220 , 226 and outer doors 210 , 216 remain locked in position, thereby reducing the risk that door failure will expose operators to immediate harm. An insulating liner 273 may be disposed within the multi-door isolation chamber 206 .
FIG. 3 depicts a burner end view of an exemplary multi-door isolation chamber 306 in which the outer doors 310 , 316 and inner doors 320 , 326 of the multi-door isolation chamber 306 have pivot mechanisms (see 266 ), which rotate outer doors 310 , 316 and inner doors 320 , 326 of the multi-door isolation chamber 306 . This embodiment further comprises an observation port 360 . The swirler 350 is disposed around the fuel nozzle tip 398 and of the startup burner 300 . The fuel nozzle tip 398 is located at the firing end of the startup burner 300 . In an exemplary method, an operator may look through the observation port 360 to determine the amount of smelt accumulation around the throat 340 . If smelt has accumulated, an operator may insert a rod through the multi-door isolation chamber 306 to dislodge the smelt accumulations while the recovery boiler is operational. By inserting a rod through the exemplary multi-door isolation chamber 306 , an operator may have a more direct path to the throat 340 and may avoid damage to the swirler 350 , which may have been previously caused by poor visibility and suboptimal access due to mechanical interference. An operator may close the bottom inner door 320 to support the startup burner 300 while dislodging smelt. The closed bottom inner door 320 partially protects the operator from stray smelt splatter from the furnace 299 . An operator may desirably close either the top outer door 316 or bottom outer door 310 to provide additional protection from stray smelt splatter when cleaning the throat 340 . In other embodiments, an operator may extend the rod through a port 351 in the outer wall 322 of the windbox 290 . When operators desire to ignite the startup burner 300 , operators generally insert an igniter assembly ( FIG. 4, 480 ) through mounting tube 383 .
FIG. 4 is a top-down view of an exemplary startup burner 400 and the swirler 450 extending through the multi-door isolation chamber 406 and the windbox 490 to engage the throat 440 . Water wall tubes 470 form the envelope of the furnace 499 and absorb furnace heat. The startup burner 400 may be removed from the windbox 490 through a housing 491 that spans the length of the windbox 490 . In some embodiments, the housing 491 may have a variable position damper 492 that may be opened and closed to allow air from the windbox 490 into the housing 491 and into the furnace 499 through the swirler 450 and throat 440 . This air maintains combustion at the fuel nozzle tip 498 of the startup burner 400 when active. When the startup burner 400 is dormant or extracted, the variable position damper 492 may be closed substantially completely to prevent air from entering the furnace 499 through the throat 440 . In other embodiments, the variable position dampener 492 may be partially open to accommodate a desired air flow.
The startup burner 400 may further be removed from the windbox 490 and housing 491 by using the handle 430 a to open the bottom inner door 220 of the multi-door isolation chamber 406 and by pulling the startup burner 400 through the internal space 425 of the multi-door isolation chamber 406 . After closing the inner doors 220 , 226 the startup burner 400 may be partially or substantially completely isolated. Once isolated, the startup burner 400 may be removed through the outer doors 210 , 216 of the multi-door isolation chamber 406 .
An igniter assembly 480 of the startup burner 400 is depicted in this exemplary embodiment. The igniter assembly 480 may comprise an ionizing flame rod and spark rod 481 and intake ports 482 . Air and natural gas may flow through these intake ports 482 . A mounting tube 483 can position the igniter assembly 480 . This igniter assembly 480 may further comprise safety equipment used to ensure continuous ignition at the fuel nozzle tip 498 of the startup burner 400 . The swirler 450 stabilizes and shapes the main flame within the furnace 499 . In an exemplary embodiment, the mounting tube 483 of the igniter assembly 480 can engage the outer wall 422 of the windbox 490 outside insolation chamber 406 . In another exemplary embodiment, the igniter assembly 480 may be co-extensive with the startup burner 400 and access the windbox 490 through the isolation chamber 406 . In an exemplary embodiment, a flapper valve 484 may be engaged to at least one end of the mounting tube 483 . This flapper valve 484 may be used to prevent pressure loss from the windbox 490 when the igniter assembly 480 is not in place.
FIG. 5 a is an exemplary embodiment of the multi-door isolation chamber 206 comprising a first inner door 526 and a second inner door 527 that may rotate on a pivot mechanism 535 such as a hinge or slide along tracks 532 (shown in FIG. 5 b ). It is to be understood by one skilled in the art that outer doors (see FIG. 2, 210, 216 ) may be configured in similar manner to the inner doors 526 , 527 as described herein. A multi-door isolation chamber 206 comprising two or more inner doors 526 , 527 may be desirable to isolate the startup burner 500 completely in the multi-door isolation chamber 206 prior to extraction. By closing the two or more inner doors 526 , 527 , operators substantially reduce the probability that operators will contact stray droplets of liquor flung through the throat 440 of the furnace 499 because these inner doors 526 , 527 may be used to close the opening 221 defined by the outer walls of the windbox 290 . The first inner door 526 may have a cut-out section 523 configured to complement the perimeter 504 of the startup burner 500 . The outer doors may have a cut-out section (see 213 ) configured to support the startup burner. The first inner door 526 may be substantially closed when removing the startup burner 500 (shown in FIG. 5 b ) such that the cut-out section 523 may be used to support the startup burner 500 as the startup burner 500 is extracted from the windbox 290 of the recovery boiler 107 . Once the startup burner 500 is inside the multi-door isolation chamber 206 , the second inner door 527 may be closed to substantially completely isolate the startup burner 500 in the multi-door isolation chamber 206 . In this embodiment, the second inner door 527 has a flange 528 configured to complement the cut-out section 523 of the first inner door 526 . In other embodiments, this flange 528 may be omitted. Although two inner doors 526 , 527 are used, it is understood that configurations of inner and outer doors known to those having ordinary skill in the art may be used to isolate the startup burner 500 from the windbox environment and furnace environment.
FIG. 5 b depicts an exemplary multi-door isolation chamber 206 , which comprises a first inner door 526 and a second inner door 527 , each having runners 531 configured to slide along tracks 532 disposed on the windbox mounting plate 218 . In other embodiments, these tracks 532 may be engaged to the inner wall of the multi-door isolation chamber 406 . In still other embodiments, one track per first and second inner door may be utilized. The first inner door 526 may have a cut-out section 523 configured to complement the perimeter 504 of the startup burner 500 . The first inner door 526 may be substantially closed when removing the startup burner 500 such that the cut-out section 523 may be used to support the startup burner 500 as the startup burner 500 is extracted from the windbox 290 of the recovery boiler 107 . Once the startup burner 500 is inside the multi-door isolation chamber 206 , the second inner door 527 may be closed to substantially isolate the startup burner 500 in the multi-door isolation chamber 206 . In this embodiment, the second inner door 527 has a flange 528 configured to complement the cut-out section 523 of the first inner door 526 . In other embodiments, this flange 528 may be omitted.
FIG. 6 a is a side view of an exemplary cooling carriage 642 that may be used to hold the startup burner 600 and permit cooling after the startup burner 600 has been removed from the multi-door isolation chamber 606 . In this exemplary embodiment, a structural brace 644 having a first end 643 and a second end 645 may be mounted to the outer wall 622 of the windbox 690 . In another exemplary embodiment, the second end 645 may be mounted to the recovery boiler 107 such that the cooling carriage 642 remains aligned with the isolation chamber 606 as the recovery boiler expands during operations. A main support beam 648 may have a first end 647 attached to the first end of the structural brace 643 and a second end 649 perpendicularly attached to the outer wall 622 of the windbox 690 . In another exemplary embodiment, the second end 649 may be mounted to the recovery boiler 107 such that the cooling carriage 642 remains aligned with the isolation chamber 606 as the recovery boiler expands during operations. A carriage assembly linkage 655 may be rotatably mounted to the main support beam 648 such that the carriage assembly linkage 655 may be secured away from the path 602 of the startup burner 600 when not in use. Rollers 657 may be mounted on at least one end of the carriage assembly linkage 655 . These rollers 657 may extend below the path 602 of the startup burner 600 and support the startup burner 600 after the startup burner 600 has been removed from the multi-door isolation chamber 606 . Operators may remove the startup burner 600 from the cooling carriage 642 after the fuel nozzle tip 698 of the startup burner 600 has cooled. In other embodiments, at least one clamp, ring, hook, or other similar securing means (not shown) may be used singularly or in combination with other securing means to support the startup burner 600 as it cools.
In an exemplary method, operators may deactivate the startup burner 600 and extract the startup burner 600 and swirler 650 through the housing 691 . Operators may then close an inner door 620 and rest the bottom of the startup burner 603 on a cut-out portion 623 of an inner door 620 . Once the inner door 620 is closed, operators may pull the startup burner 600 through the internal space 425 of the multi-door isolation chamber 606 and through the outer door of the multi-door isolation chamber 610 . Operators may then place the startup burner 600 on the rollers 657 of the carriage assembly linkage 655 and allow the startup burner 600 to cool. Once cool, the operators may remove the startup burner 600 from the cooling carriage 642 and store the cooling carriage 642 away until further needed.
In another exemplary method, the inner door 620 need not be closed before the operator removes the startup burner 600 from the multi-door isolation chamber 606 .
FIG. 6 b is a front view of an exemplary cooling carriage 642 . The elements correspond to the elements described in FIG. 6 a . In this exemplary embodiment, the rollers 657 may be contoured to support the startup burner 600 either singularly or in combination with at least one other roller.
FIG. 7 depicts an alternative exemplary isolation chamber in the form of a burner guide sleeve 775 . This exemplary burner guide sleeve 775 comprises a plug 771 at an outer end 777 of the burner guide sleeve 775 and a flapper valve 784 at an inner end 778 of the burner guide sleeve 775 . The burner guide sleeve 775 generally extends into the windbox 790 and may support the startup burner 700 at least partially. The plug 771 may be used to prevent hot air flow from the windbox 790 when the startup burner 700 is in use. The plug 771 may be fixed to the startup burner 700 . In another embodiment, the plug 770 may be slidably engaged to the startup burner 700 . The plug may be made from a high-density, lightweight material configured to withstand air temperature in the windbox 790 . The plug 771 may desirably fill the inner perimeter of the guide sleeve 775 so as to form a seal. In embodiments where the plug 771 is fixed to the startup burner 700 , the length 708 of the plug may be at least the length 709 of the distance between the flapper valve 776 and the throat 740 . In embodiments where the plug 771 is not fixed to the startup burner 700 but is still configured to maintain a seal, the length 708 of the plug 771 may be less than the length 709 between the flapper valve 776 to the throat 740 . In exemplary embodiments in which the startup burner has been extracted from the windbox, the plug 771 may desirably fill the inner perimeter of the guide sleeve and extend through the windbox in substantially the same manner as the startup burner 700 such that the plug 771 may have an end corresponding to the firing end of the startup burner 700 and swirler 750 that substantially blocks the hole left by the extracted swirler 750 . The plug 771 may be made of a material generally known in the art, including a poly-amide-based plastic, or other suitable material configured to withstand the heat of the recovery boiler.
The flapper valve 784 may rest on the startup burner 700 when the startup burner 700 interfaces with the throat 740 and furnace 799 . When the startup burner 700 is removed past the flapper valve 784 , the flapper valve 784 generally closes and rests on the front lip 794 of the guide sleeve 775 at an angle θ. The burner guide sleeve 775 may extend partially through the housing 791 within the windbox 790 .
It will be understood that the modifications of FIGS. 3 through 7 could be employed in combination with one another as well as individually in the assembly of FIG. 1 and the assembly illustrated in FIG. 2 .
While this invention has been particularly shown and described with references to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims.
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The present disclosure describes a recovery boiler startup burner assembly that can mitigate the harmful effects of smelt fouling, airflow interference, and operator exposure to hot air from the furnace and win box through use of an extractable startup burner and an isolation chamber engaged to a windbox. The present disclosure also describes a method for safely extracting a startup burner from an active recovery boiler as has method for inserting an extractable startup burner into a recovery boiler during operation.
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BACKGROUND OF THE INVENTION
This invention relates generally to bimetal electrodes for spark plugs, and more particularly to bimetal electrodes for spark plugs which utilize a heat resisting metal for the exposed portion and a highly thermally conductive material for the core and to novel and improved methods and apparatus for producing such electrodes.
Modern spark ignition internal combustion engines have greatly lengthened periods between service, and it has been recognized that spark plug life is an important factor in determining this interval. In such modern engines, the primary problem of spark plug life becomes that of erosion of the electrodes to a point that the gap increases beyond tolerable limits. In an effort to increase spark plug life by decreasing the erosion of the electrodes, it has been proposed to reduce the electrode temperatures by forming the electrode with an outer surface of a material such as nickel and a core of a highly thermally conductive material such as copper to rapidly conduct the heat away from the firing tip to the exposed end of the spark plug where the heat can be more easily dissipated.
Many methods have been proposed for the manufacture of such electrodes, one of which is disclosed in the application of N. I. Kin and G. T. Payne, Ser. No. 232,954, filed Feb. 9, 1981, and assigned to the assignee of the present invention. In general, this method includes the steps of forming a hollow cup from a heat-resisting metal such as nickel, and thereafter inserting in the open end of the hollow cup a cylindrical slug of a thermally conductive metal such as copper. The copper is then upset within the cup to eliminate all voids, and the resultant composite blank is extruded, closed end first, through a die to reduce the diameter to that of the finished electrode, after which further operations can be performed on the open end, where both the copper and nickel are exposed.
While this method is applicable to metals such as substantially pure nickel, it has not been used successfully with more refractory metals and alloys, which are harder to work but more desirable in a spark plug because of their increased strength and resistance to erosion at high temperatures.
SUMMARY OF THE INVENTION
The present invention provides a method and apparatus for the production of bimetal electrodes utilizing a copper core for its highly thermal conductivity, together with an outer layer of a heat resisting metal such as Inconel or other nickel-base alloy.
In accordance with one aspect of this invention, the nickel-base alloy is cut as a slug from wire and then, during a squaring operation, is provided with a rounded indentation on one end face of the cylindrical blank. During a subsequent operation, a punch having a generally rounded end is used to form the cup by extrusion, and the end of the punch and the indentation on the blank are formed to provide a centering action for the punch to thereby produce a generally deep, small diameter cup having relatively thin walls but with a central cavity having a depth of two or more times the diameter. After the cup has been so formed, a copper slug, also cut from wire, is inserted into the cup and then upset to substantially fill the cavity without voids.
According to another aspect of this invention, the assembled core and cup are thereafter extruded by a two-stage reduction to form the final diameter of the electrode. During the first extrusion operation, the assembled cup and core are inserted, closed end first, into the die and pressed with a punch having a diameter substantially equal to that of the cup, so that at the end of the extrusion operation substantially all of the assembled cup and core have been reduced a first step in diameter, with only the open end portion remaining at the original diameter of the cup.
During the second extrusion operation, the assembly is placed into a die to be reduced in two stages to the final diameter of the electrode, by a punch having a diameter equal to the diameter of the first stage of reduction. During the initial movement of the assembly in the punch, the remaining portion around the open end of the cup and core is reduced in diameter to that of the first drawing operation, after which a further drawing operation is done by further movement of the punch to further extrude the assembled cup and core to the final diameter except for a remaining portion around the upper end, which retains the diameter of the punch. Subsequent to the second extrusion operation, the unreduced ring at the open end may be trimmed and removed, leaving the electrode at its finished diameter for its entire length.
According to another embodiment of the invention, it is possible to form an electrode without the necessity of trimming by a scrapless forming process. Using the same cup as in the first embodiment, a slightly shorter copper core is used so that after the core is upset within the cup during the assembly operation, the end of the copper is recessed a predetermined distance below the open end. The assembled cup and core then proceed through the two-stage extrusion process in substantially the same manner as in the first embodiment, except that a different shaped nose is required on the punch to make up for the reduced volume of copper in the core.
At the end of the second stage of extrusion, the assembly is put in a second die, where the exposed larger diameter of the cup above the copper, instead of being trimmed, is bottled inwardly, and in a subsequent operation pressed flat to substantially seal the copper at the open end so that the finished electrode not only has the nickel-based alloy completely enclosing it and encapsulating the copper core, but also retaining all of the material of the assembly prior to the forming operations.
These and other aspects and advantages of the invention are more fully described in the following detailed description and shown in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-3 are views of the progressive steps utilized to form the cup of heat resisting alloy in accordance with the first embodiment of this invention;
FIGS. 4-6 are views of the progressive steps of forming the core and assembling it within the cup shown in FIG. 3;
FIGS. 7-10 show the progressive stages in which the assembled cup and core of FIG. 6 are formed into the finished electrode;
FIG. 11 illustrates one set of tooling utilized to progressively form the parts illustrated in FIGS. 7 through 10;
FIGS. 11A and 11B are enlarged, fragmentary views of the steps at the second station of FIG. 11 in transforming the cup and core of FIG. 7 into that of FIG. 8; and
FIGS. 12-21 are views of the progressive steps similar to FIGS. 1-10, but according to another embodiment of the invention for forming an electrode without any trimming operation or leaving any scrap.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings in greater detail, FIGS. 1-3 show the progressive stages in forming the cup. The first stage in forming the cup is to cut off a slug or blank 10 from round wire or rod stock, preferably at the intitial cut-off of a progressive header. While the cup may be made of any heat resisting metal such as nickel, the methods of the present invention are particularly suitable for alloys that are more difficult to work but have improved heat resisting properties, such as Inconel 600, an alloy of 76% Ni, 16% Cr and 7% Fe. The size of the slug is generally chosen by the amount of material required in the finished electrode, and in a typical example, it has been found that the use of wire about 11/2 times the size of the finished electrode, with the length being approximately twice the diameter, provides the proper shape for the slug, which, as is usual in such shearing operations, has oppositely extending, finned ends 11 resulting from the shearing operation.
The second stage in forming the cup is shown in FIG. 2, where the slug 10 has now gone through a squaring operation in a closed die to form the squared slug 12. In the squaring operation, the diameter is increased slightly and the one end is formed with a radiused edge, as shown at 13, while the other end has a generally squared edge 14, and this end is formed with a rounded central recess 16. Preferably, the recess 16 is spherical, with an outer diameter approximately equal to that of the punch used in the subsequent operation. Generally, the spherical radius is approximately equal to the diameter of the slug and, while a spherical recess 16 is preferred, it is recognized that other shapes, such as a parabola, could be used as long as there are no sharp edges or points within the recess.
The final stage in forming the cup is shown in FIG. 3, where the blank of FIG. 2 has been extruded, preferably by closed die extrusion over a punch having an end portion that conforms to the surface of the recess 16. The cup 17 thus has an end wall 18 on the outer side of which is formed a flat circular end face 19 which may be approximately the diameter of the finished electrode. The corners are formed with a radius at 21 generally blending from the end face 19 into the outer surface 24, but it has been found that other shapes in a pure radius may be of advantage, including having the end face 19 project axially slightly beyond the beginning of the radius 21.
The recess within the cup 17 includes an inner end face 22 conforming to the shape of the punch that was used, and generally being spherical in shape, corresponding in shape to the recess 16 formed on the squared slug 12. The recess includes cylindrical inner sides 23 and terminates at an open end indicated at 26. It has been found that by the use of the preformed recess in the slug 12 conforming to the rounded end of the punch, it is possible, even with a material such as Inconel 600, to form a generally small diameter, deep recess in the cup in which the depth of the recess may be as great as three or four times its diameter, which in turn is selected to be slightly greater than the finished outside diameter of the electrode. Such a cup may be formed with a very uniform wall thickness, with the inner side of the bore 23 in close concentricity with the outer surface 24, and it is believed that this is facilitated by the guiding action of the recess 16 on the squared slug 12, tending to prevent deflection of the punch and retaining it in central alignment with respect to the cup.
After the extrusion operation in which the finished cups, as shown in FIG. 3, are produced, they are cleaned to remove lubricants and other material, particularly from the inner cavity. In an assembly machine, copper wire is cut off to form core slugs 29, as shown in FIG. 4, with the core slug 29 having an outside diameter slightly less than the inner bore 23 of the cup, particularly to allow clearance for the finned ends 31 from the shearing operation, to allow these core slugs to be easily inserted into the cup without interference between the end fin 31 and the bore 23. Because the core slug 29 does not undergo any squaring operation, it will necessarily be a loose fit, as shown in FIG. 5, with considerable clearance between the core slug and the rounded face 22 at the bottom of the cup. Hence, the core slug 29 is made long enough so that when inserted the full distance without deformation into the cup, the end 33 projects above the open end 26 of the cup and a clearance space exists adjacent both the bottom face of the cup 22 and the sidewalls 23.
After the assembly shown in FIG. 5 is made, there is then performed a staking or seating operation in which no deformation is made to the cup, but the pressure is applied entirely to the core slug 29 within the cup 17 so as to completely fill the space within the cup without any voids or air pockets, either adjacent the end 22 or along the sides adjacent the inner bore 23 of the cup. When this is done, the copper will be slightly recessed below the open end 26, as shown at 34 in FIG. 6. After this step has taken place, the assembled cup and core are ready for further forming actions to produce the finished electrode.
The assembled blank 35 shown in FIG. 6 is formed into a finished electrode, according to one embodiment of the invention, in four stages. The blank is partially reduced in a first extrusion operation to form the blank 37 shown in FIG. 7 and then reduced to the final diameter in a second extrusion operation to produce the blank shown in FIG. 8, which now has a diameter of the finished electrode. The third operation is essentially a trimming operation to form the blank 39 shown in FIG. 9, followed by a final forming operation to form the finished electrode 40 shown in FIG. 10.
The tooling that is used in the four operations on the assembled blank 35 is shown in FIG. 11, where the blank 37 is produced at the first station 41, while the blank 38 is formed at the second station 42, which is also shown in greater detail in FIGS. 11A and 11B. The trimming operation to form the blank 39 is done at the third station 43, while the final forming operations are done at the fourth station 44.
At the first station 41, the assembled cup and core 35 are picked up by suitable transfer means (not shown) and inserted into an extrusion die 46 having a recess 47 at least as deep as the length of the cup so that the recess 47 will completely receive the assembly before the cup engages the extrusion orifice 48. A punch 51 has a nose portion 52 shaped to generally conform with the recessed end 34 of assembly 35 to guide it in entering the recess 47. The punch 51 has a diameter substantially as great as that of the recess 47 to confine the assembly so that continued forward movement of the punch then forces the assembly through the extrusion orifice 48 and into the subsequent free space 49. However, the punch nose 52 stops just short of the orifice 48 before it retracts, leaving around the orifice 48 the small non-extruded portion adjacent the open end of the assembly. As the punch retracts, a typical knockout rod 53 then forces the blank 37 out of the die 46 for transfer to the next station 42. The blank 37 at this point has a cylindrical sidewall 56 and a generally flat, closed end 57 having a reduced radius 58 at the end adjacent the sidewall 56. The reduction at this stage will preferably be about half of the reduction to the final diameter, and the flared skirt portion 59 retains the original diameter of the cup and is the non-extruded portion that cannot pass through the orifice 48. The open end 61 now has a generally spherical recess 61 conforming to the punch nose 52.
At the next station 42, it is necessary to first reduce the flared skirt 59 before the final extrusion and reduction of diameter are performed so that the blank can be substantially trapped in a closed die during the extrusion operation. While FIG. 11 shows the operation at the second station 42 at the end of the cycle, FIGS. 11A and 11B show the intermediate stages. Station 42 has first and second axially spaced dies 64 and 66 to permit the intitial reduction in diameter of the flared skirt 59 on the blank 37, followed by the second and final extrusion of the complete blank. Although two dies 64 and 66 are shown as a matter of convenience, it is recognized that these dies could be formed as a single piece.
The first die 64 has an axial bore 67 having a diameter substantially the same as the diameter of the sidewall 56 of the blank 37 so that the blank slips into the bore 67 for its whole length. The outer end of the bore 67 is provided with a conical lead-in 68 to engage the outer surface of the flared skirt 59 and a suitable punch 69 has a shaped nose 70 having a reduced diameter spherical end to engage the recess 61 in the open end of the blank 37 to apply primary pressure to the core. As the punch 69 moves forward to the position shown in FIG. 11B, the flared skirt 57 is reduced in diameter to the rest of the sidewall 56 and the punch nose 70 now effectively traps the material of the blank, since the punch 69 has the same diameter as the bore 67, except for the necessary clearance.
It should be noted that the bore 67 is longer than the blank 37, even after the flared skirt 59 has been removed so that, as shown in FIG. 11B, the full diameter of the punch 69 has passed the lead-in 68 before the blank end face 57 reaches the second die 66. This second die 66 has a reduced diameter orifice 71 so that the extruded diameter of the blank as it passes the orifice is the final diameter of the electrode. The orifice 71 has a shoulder 72 at the outer end adjacent the first die 64, as well as a clearance space 73 on the other side, to receive the extruded blank at this station. A suitable knockout rod 74 is provided so that the extruded blank can be removed after the extrusion is completed.
As shown at station 42 in FIG. 11, at the end of the stroke of the punch 69, the blank has been extruded now into the clearance space 73 to produce a cylindrical sidewall 76 (see FIG. 8) of the blank 38, which now also has a slightly rounded end 77 and a flared skirt 78 defining a recess 79 at the open end of the blank 38. It should be noted at this point that the recess 79 has a depth substantially equal to that of the skirt 78 so that the core material is almost entirely within the reduced diameter sidewall portion 76.
The blank 38 is then transferred to the third station 43, where the trimming operation is performed. Station 43 includes a die 82 having an axial bore 83 substantially equal to the diameter of the blank 38, together with a flat, exposed end face 84. At the station 43 is located a flat punch 86 carried within a stripper sleeve 88, and a suitable knockout rod 89 is also provided. When the blank enters the bore 83, it passes freely therethrough until the skirt portion 78 abuts up against the end face 84 of die 83. Further movement of the punch 86 engaging against the recess 79 forces the blank further into the bore 83 so that the end face 84 shears off the skirt portion 78 to form a ring 90, and the resulting blank 39 has an exposed end face 91 in which the core material is exposed. When the punch is retracted, the stripper sleeve 88 then serves to force the ring 90 off the punch 86 so that the station is ready for the next part.
The blank 39 is then transferred to the fourth station 44, which has a die 93 also having a bore 94 of substantially the same diameter as the blank. At the outer end of bore 94 is an annular recess 95 and the punch 96 also has a recess 97 therein. Also at this station is a knockout rod 98 which, unlike the knockout rods at the other stations, is positioned to engage the end of the blank. The punch 96 is of substantially larger diameter than the blank, with the recess 97 having substantially the same diameter. Thus, when the blank is trapped between the punch 96 and the knockout rod 98, not only is the end adjacent the kockout rod 98 flattened and squared, but the material of both the core and the jacket is forced outward into the annular recess 95, since that is the only point at which the blank is unconfined.
The resultant blank as ejected from station 44 has the configuration shown in FIG. 10, where the blank 40 has a cylindrical sidewall 101 and a flat end 102. The material that was the cup then makes up a solid portion 103 adjacent the flat end 102, so that the nickel alloy provides a solid portion adjacent the firing end of the electrode. The alloy material then forms a cover portion 104 of relatively reduced thickness overlying the core 106, which is exposed at the end 108. Adjacent this end, the material of both the jacket and the core forms an enlarged annular flange 107 suitable for securing the electrode within the finished spark plug.
Another embodiment of the invention is shown in FIGS. 12-21, which, while substantially similar to the previously described embodiment, provides a scrapless method of making an electrode in which no trimming operation is required. The cup and the method of making it, as shown in FIGS. 12, 13, and 14, is preferably identical with the cup shown in FIGS. 1, 2, and 3, and begins with a slug 110 which is sheared from wire and then first undergoes a squaring operation to produce the squared blank 112 shown in FIG. 13. Again, the squared blank has a rounded end 113 and a squared end 114 having a spherical recess 116 therein.
The blank 112 is then formed into a cup 117, as shown in FIG. 14, by an extrusion operation, as previously described in connection with FIG. 3. The resultant cup 117 thus has an end wall 118 on the other side of which is an end face 119 of reduced diameter and a suitable radius 121 extending from its end face 119 to the cylindrical outer surface 124. The recess includes an inner end face 122 and a cylindrical inner surface 123 which extends to the open end 126.
In a similar way, a core slug 129, as shown in FIG. 15, is formed from copper wire, but in this embodiment the core has a somewhat shorter overall length than that of the core slug 29 shown in FIG. 4. When the core slug 129 is then assembled loosely within the cup 117, as shown in FIG. 16, when the end of the core slug fits adjacent the recess bottom 122, the exposed end 133 of the core slug 129 will tend to be approximately flush with the open end 126 of the cup 117. After the staking operation is done to result in the assembly 135 shown in FIG. 17, with the core slug 129 upset to tightly fill the recess in the cup 117, the core end 134 is now recessed a substantial distance below the open end 126 of the cup 117.
The cup and core assembly 135 is then subjected to further operations similar to those shown in FIGS. 7 through 10 and utilizing tooling that is substantially identical, with minor changes as discussed hereinafter, to that shown in FIG. 11. The assembly 135 is extruded in a two-stage process, the first stage of which produces the blank 137 shown in FIG. 18. This blank has cylindrical outer wall 142 terminating adjacent the open end in a flaring skirt 143 defining therein a recess 144. It will be noted that this blank appears very similar to the blank shown in FIG. 7, except that, because of the reduced amount of material in the core, the recess 144 is substantially deeper than the recess 61 in the blank 37. At the next station, the blank 137 is further extruded and the skirt 143 reduced in diameter in a similar manner as shown in FIGS. 11A and 11B, and after the second extrusion the finished blank 138 has a cylindrical sidewall 146 having substantially the diameter of the finished electrode. At the upper end, the sidewall 146 terminates in a flaring skirt 147 having a cylindrical portion 148 adjacent the open end and defining a recess 149 therein.
The next step is to place the blank 138 in a supporting die having an annular recess at the open end and striking it with a punch also having a recess to perform a bottling or closing operation to produce the blank shown in 139. In this step, the core is not disturbed, but the skirt portion of the cup is formed inwardly at the open end defining a spherical head 151 enclosing a hollow recess 152 and defining a small centrally located opening 153 where the cup material has been constricted.
The final step is a heading operation in which the blank 139 is formed into the finished electrode 140. In this operation, the blank is fully enclosed and forced axially inward against a knockout rod to form a flat end 155 at the solid end of the electrode. The electrode retains the cylindrical sidewalls 156, which extend from the flat end 155 to an annular projecting rim 158, and a closed end 159 where the cup material has been gathered together and pressed downwardly to eliminate any air space within the electrode. The cup material is in contact with the exposed end of the core material, and the core is either completely enclosed or, at most, only a very small opening 161 is left in the center of the closed end 159. The finished electrode is then ready for further cleaning operations and thereafter for assembly into the finished spark plug.
Although the several preferred embodiments of this invention have been shown and described, it should be understood that various modifications and rearrangements may be resorted to without departing from the scope of the invention as claimed herein.
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A method of producing bimetal electrodes in which a core of copper is enclosed within an outer covering of a nickel alloy. The alloy is extruded into a relatively small diameter, deep cup by first forming a cylindrical blank with a rounded indentation in one face and thereafter extruding the cup using a punch having an end conforming with said indentation to form a central opening having a diameter at least three times the diameter of the punch. A cylindrical copper core is then firmly seated within the cup, which is then extruded by two stages to form an elongated, cylindrical blank. In one embodiment, the end is finished by trimming away a flaring skirt portion at the open end and thereafter upsetting the blank. In another embodiment, the flared skirt portion of the nickel alloy is bottled inwardly and pressed flat against the exposed end of the core so that no scrap is produced.
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CROSS-REFERENCE TO RELATED APPLICATION
The present application is a continuation of U.S. application Ser. No. 09/706,072, filed Nov. 3, 2000, titled INSTRUMENTED CEMENTING PLUG AND SYSTEM (abandoned).
FIELD OF THE INVENTION
The present invention relates generally to the field of oil and gas well cementing. More particularly, the present invention relates to an instrumented cementing plug and a system for sending to a surface location data measured by the instrumentation of the cementing plug.
DESCRIPTION OF THE PRIOR ART
During the drilling and at the completion of every oil and gas drilling operation, it is necessary that cementing be done in the borehole. More particularly, the casing or liner must be cemented in the hole in order to support the casing or liner and the hole and to prevent the flow of fluids between formations.
The operations associated with setting and cementing casing and liners in the borehole are generally well known in the art. At the completion of a phase of drilling, the cased and open portions of the well bore are filled with drilling fluid. A casing or liner string is assembled and run into the well bore. Then, a spacer or displacement plug is inserted into the top of the casing or liner above the drilling fluid. The displacement plug serves to separate and prevent mixing of the drilling fluid below the displacement plug and a cement slurry that is pumped into the casing or liner above the displacement plug. After a predetermined quantity of cement slurry has been pumped into the casing or liner, a cementing plug is inserted above the cement slurry. Then, drilling fluid is pumped into the casing above the cementing plug to force the slug of cement slurry down the casing or liner and up the annulus between the casing or liner and the borehole. After cementing, the displacement and cementing plugs, the cementing shoe, and any residual cement in the casing are drilled out.
Good cementing jobs are essential to the successful drilling and completion of oil and gas wells. Currently, operators rely upon proper equipment and skill of personnel in order to achieve a good cementing job. However, occasionally, bad cementing jobs occur. Some of the causes of bad cementing jobs are over-displacement or under-displacement of the cement slurry, which results in the formations not be properly isolated from each other. Another cause of bad cementing jobs channeling within the cement, which results in flow paths within the cement between formations.
Various tests are performed to determine whether or not the cementing job is good. If a cementing job is not good, then remedial operations, such as squeeze jobs, must be undertaken. However, remedial operations, tend to be expensive in terms of equipment and supplies and time.
It is an object of the present invention to provide a system for improving the quality of cementing operations.
SUMMARY OF THE INVENTION
The present invention provides a system for cementing a tubular member, such as a casing or liner string, in a well bore. The system of the present invention includes a cementing plug. The cementing plug includes at least one sensor. The system transmits a value measured by the sensor to a surface location. The system may transmit the value measured by the sensor through a cable connected between the plug and the surface location. Alternatively, the system may transmit the value measured by the sensor in a wireless manner to the surface location. In a cable-connected embodiment, an optical transmitter may be coupled to the sensor and the cable may include an optical fiber. In a wireless embodiment, the signal may be acoustically coupled to the surface. For example, an explosive device for producing an acoustic signal may be coupled to the sensor.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a pictorial representation of one embodiment of the system of the present invention.
FIG. 2 is a block diagram of the system of FIG. 1 .
FIG. 3 is a pictorial representation of an alternative embodiment of the system of the present invention.
FIG. 4 is a block diagram of the system of FIG. 3 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, and first to FIG. 1, a casing string 11 is shown inserted into a well bore 13 . Casing string 11 is of the type generally well known in the art, and it includes a plurality of casing sections 15 connected together by casing collars 17 . A cementing shoe 19 is affixed to the bottom end of casing string 11 . A plug container 21 is affixed to the upper end of casing string 11 . Plug container 21 is of the type generally well known in the art, and it includes a cement inlet 23 and a drilling fluid inlet 25 . Plug container 21 is adapted to launch a displacement plug 27 and an instrumented cementing plug 29 into casing string 11 .
Cementing plug 29 is generally cylindrical and it includes an upper surface and a lower. The side surfaces of cementing plug 29 are in the form of wipers that engage the inside wall of casing string 11 . Cementing plug 29 performs its normal displacement and separation functions. Additionally, as will be explained in detail hereinafter, cementing plug 29 includes various sensor and telemetry instrumentation.
In the embodiment illustrated in FIG. 1, plug container 21 includes a lubricator 31 . Lubricator 31 is adapted to sealingly and slidingly engage a cable 33 connected to cementing plug 29 . In the preferred embodiment, cable 33 includes an optical fiber. Lubricator 31 allows cable 33 to be run into casing string 11 as cementing plug 29 is pumped downwardly. Cable 33 is preferably releasably connected to cementing plug 29 so that cable 33 may be retrieved through lubricator 31 .
Referring now to FIG. 2, there is shown a block diagram of a system according to the present invention. In the embodiment shown in FIG. 2, cementing plug 29 includes a plurality of sensors. An upper pressure sensor 41 and an upper temperature sensor 43 are positioned to sense pressure and temperature, respectively, at the upper surface 45 of cementing plug 29 . A lower pressure sensor 47 and a lower temperature sensor 49 are positioned to sense pressure and temperature, respectively, at the lower surface 51 of cementing plug 29 . The operation and construction of pressure and temperature sensors are generally well known.
Pressure sensors 41 and 47 , and temperature sensors 43 and 49 , are adapted to output an electrical signal indicative of the pressure or temperature that they sense. The difference in pressure measured by pressure sensors 41 and 47 is useful in determining if there is bypass of displacement fluid around cementing plug 27 . Fluid bypass can result in effective over-displacement or under-displacement of the cement slurry or mixing of displacement fluid and the cement slurry, which can cause channeling or an otherwise ineffective cement job.
The setting of cement involves exothermic reactions. Thus, the progress of the setting of the cement can be monitored with reference to the temperature measured by sensors 43 and 49 . Those skilled in the art will recognize other information that may be obtained from the pressure and temperature sensors.
Cementing plug 29 also includes a location sensor 53 . Location sensor 53 preferably operates magnetically to detect the casing collar. Whenever cementing plug 29 passes a casing collar, location sensor 53 puts out a particular signal. The output of location sensor 53 enables an operator to know the location of cementing plug 29 within casing string 11 . Location information is essential to prevent over- or under-displacement of the cement slurry. Location information may also be obtained by measuring the length of cable 33 run into the hole.
The outputs of the sensors are coupled to a processor 55 . Processor 55 converts the signals received from pressure sensors 41 and 47 and from temperature sensors 43 and 49 to pressure and temperature values, respectively. Processor 55 counts the signals received from location sensor 53 , thereby to determine the location of cementing plug 29 within the casing. Processor 55 also packages the pressure, temperature, and location data according to an appropriate communications protocol for transmission to a surface location. Processor 55 may also perform other processing. For example, processor 55 may compute pressure or temperature differentials between upper surface 45 and lower surface 51 of cementing plug 29 .
Cementing plug 29 also includes a communication interface 57 coupled to processor 55 . In the embodiment shown in FIG. 2, communications interface 57 is coupled to an optical transmitter 59 and to an optical receiver 61 . Optical transmitters and receivers are generally well known in the art. The output of optical transmitter 59 and the input of optical receiver 61 are coupled to a multiplexer 63 . Multiplexer 63 is coupled to a releasable optical coupler 65 , which in turn is coupled to optical cable 33 . In the embodiment shown in FIG. 2, coupler 65 is operated to release cable 33 by a signal from processor 55 . A power supply indicated generally by the numeral 67 supplies power to the components of cementing plug 29 .
Cementing plug 29 is expendable in that it is not intended to be retrieved at the completion of use. Also, the instrumentation components of cementing plug 29 that are left downhole after optical cable 33 has been retrieved are drillable so that they may be drilled out. While the sensors and processors have been illustrated as discrete components, the sensing and processing functions may be integrated into a smart sensor built on a single semiconductor chip.
The system illustrated in FIG. 2 includes surface equipment, indicated generally by the numeral 71 . Surface equipment 71 includes a multiplexer 73 coupled to optical cable 33 . Multiplexer 73 is coupled to an optical transmitter 75 and an optical receiver 77 . The output of optical receiver 77 and the input of optical transmitter 75 are coupled to a communications interface 79 , which in turn is coupled to a workstation or personal computer 81 . Workstation 81 is adopted to run an operating system, such as Windows 98 (tm) or Windows NT (tm), and various application programs according to the present invention. The application programs provide a user interface that displays data and enables an operator to interact with the system. The application programs also process data received from cementing plug 29 , to calculate and display location, pressure, and temperature information. As is apparent, the system of FIG. 2 enables bi-directional communication between surface location 71 and cementing plug 29 . The bi-directional communication enables, among other things, an operator at surface to cause the actuation of coupler 65 to release cable 33 . Preferably, coupler 65 includes an explosive element adapted to release cable 33 .
Referring now to FIG. 3, there is illustrated an alternative embodiment of the present invention. The embodiment of FIG. 3 is similar to the embodiment of FIG. 1, except that information from cementing plug 29 a is coupled to surface equipment acoustically, rather than optically. Thus, plug container 21 a includes a transducer 93 that is coupled to surface equipment by a cable 95 that passes through a stuffing box 91 .
Referring now to FIG. 4, there is shown a block diagram of the system of FIG. 3 . Cementing plug 29 a includes a location sensor 91 that operates substantially in the same way as the location sensor of the system of FIG. 2 . The output of location sensor 91 is coupled to a processor 93 . Processor 93 is coupled to a detonator 95 , which is adapted to selectively detonate explosive caps 97 . Explosive caps 97 are disposed in an array adjacent the upper surface 99 of cementing plug 29 A. In the preferred embodiment, each cap 97 has a distinctive acoustic signature that enables the signal of a particular cap 97 to be distinguished from that of another. Thus, the detonation of caps 97 may be coded with information obtained from location sensor 91 .
Generally, the acoustic coupling of the system of FIG. 4 provides lower bandwidth than the optical coupling of the system of FIG. 2 . Thus, in FIG. 4, only the location sensor 91 is shown. However, by increasing the size of the array of caps 97 additional information may be transmitted and the number and types of sensors may be increased. A power supply 101 supplies power to the components of cementing plug 29 a.
The system of FIG. 4 includes surface equipment, designated generally by the numeral 111 . Surface equipment 111 includes transducer 93 , which is coupled to an audio interface 113 . Audio interface 113 is coupled to a workstation or processor 115 . Surface equipment 111 receives and processes acoustic signals from cementing plug 29 a . In the system illustrated with respect to FIG. 4, an operator is provided with location information. Those skilled in the art will recognize other wireless downhole telemetry systems, such as mud pulse and electromagnetic systems.
From the foregoing, it will be apparent that the present invention provides an improved cementing system. The system of the present invention provides real-time measurements of downhole conditions and plug locations, thereby enabling an operator to take corrective actions before the cement has set. The system of the present invention thus reduces or eliminates the need for costly post-cementing remedial actions.
The system of the present invention has been illustrated and described with respect to presently preferred embodiments. Those skilled in the art will recognize, given the benefit of the foregoing disclosure, alternative embodiments. Accordingly, the foregoing disclosure is intended for purposes of illustration rather than limitation.
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A system for cementing a tubular member in a well bore includes a cementing plug. The cementing plug includes at least one sensor. The system transmits a value measured by the sensor to a surface location. The system may transmit the value measured by the sensor through a cable connected between the plug and the surface location. Alternatively, the system may transmit the value measured by the sensor acoustically to the surface location.
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BACKGROUND
[0001] This application claims the benefit of U.S. Provisional Application No. 62/028,075, filed on Jul. 23, 2014. The present disclosure relates to internal combustion engines and especially to improvements in internal combustion engines having electrolytic cells for generating hydrogen and oxygen for combination with the fuel-air mixture for the engine.
[0002] Hydrogen is an excellent source of alternative energy for internal combustion engines. It is a highly efficient fuel with high energy release per pound, and it burns cleanly. Moreover, hydrogen can supplement gasoline in a conventional automobile engine without significant alteration to standard engine parts.
[0003] The use of hydrogen as a fuel supplement for internal combustion engines has been of ongoing interest in the automobile industry. The use of electrolysis of water as a means of providing hydrogen to automobile engines, however, has been attempted with limited success. A practical, efficient and inexpensive means of using water in an automobile engine has not yet been successfully integrated into the industry. Related systems utilizing hydrolysis generally have closed systems that doesn't allow for flow of the electrolyte solution or cleaning of the electrolyte solution to remove accumulated sludge.
[0004] One of the hurdles to overcome in the use of water as source of hydrogen in automobile engines is the low and inconstant yield of hydrogen. Further, electrolysis generally produces contaminants that coat the electrodes and the electrolysis tank and foul the water, leading to lower yields and equipment problems. Another issue to overcome has been the heat generated during electrolysis resulting in boiling of the water, thereby decreasing the efficiency of electrolysis. Any significant improvement in the use of hydrolysis in automobile engines would be of great value to the transportation industry.
SUMMARY OF THE INVENTION
[0005] The present disclosure overcomes problems associated with existing electrolysis systems in automobile engines and improves upon existing systems.
[0006] A fuel system is provided for generating hydrogen and oxygen for use in an internal combustion engine to improve combustion efficiency of the engine and to decrease emissions from the engine. An illustrative embodiment of the fuel system has at least one electrolysis cell for generating hydrogen and oxygen through electrolysis of an aqueous solution, a power source for providing electrical power to the electrolysis cell, and a cooling system for maintaining the temperature of the electrolysis cell in a workable range. A key feature of the present disclosure is the utilization of sludge generated by electrolysis to improve fuel efficiency in engines. The present disclosure has a longer line between the engine and the cooler than related systems. It is estimated that the method of utilization of the sludge generated during electrolysis as a fuel increases the efficiency of energy production of electrolysis by approximately 60%.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 is a schematic overview of the system of the present disclosure.
[0008] FIG. 2 is a cross-sectional side view of the system showing cooling components.
[0009] FIG. 3 is a cross sectional side view of the system showing hydrogen delivery tube adjacent the filter.
[0010] FIG. 4 is a top view of the hydrogen agitator mixer.
[0011] FIG. 5 is a schematic diagram of the wiring of the system of the present disclosure.
DETAILED DESCRIPTION OF THE INVENTION
[0012] At the outset, it should be clearly understood that like reference numerals are intended to identify the same structural elements, portions, or surfaces consistently throughout the several drawing figures, as may be further described or explained by the entire written specification of which this detailed description is an integral part. The drawings are intended to be read together with the specification and are to be construed as a portion of the entire “written description” of this invention as required by 35 U.S.C. §112. As used in the following description, the terms “horizontal”, “vertical”, “left”, “right”, “up”, “down”, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “vertically”, “upwardly”, etc.) simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate.
[0013] FIG. 1 , shows engine system 10 of the present disclosure, which shows a novel configuration of elements including an electrolytic cell, or Joe cell 106 , to improve fuel efficiency primarily for use in vehicles. In the preferred embodiment, designed for use with automobiles, the engine system 10 utilizes gasoline electrolysis to produce hydrogen, oxygen and a sludge by-product. The sludge produced by electrolysis has generally been considered a hindrance to efficiency in electrolysis because it collects in the electrolyte solution, in this case water, or on the electrodes of a typical electrolysis cell and inhibits hydrolysis. A 24 volt alternator 12 charges the batteries. 24 volts in the alternator is important for continued hydrolysis in engine system 10 . 24 volts in the alternator is optimal versus 12 (standard) or 36 volts. 36 volts generates greater than optimal heat. Only one 24 volt alternator is needed, and the other alternator is a stock alternator which is 12 volt.
[0014] Air dryer 14 removes water from the hydrogen and air stream before it enters injectors. The air dryer is a novel feature of engine system 10 , with respect to standard hydrolysis systems in engines. The volume of hydrogen and air that engine system 10 generates would cause stalling without the air dryer 14 to remove moisture content. The air dryer 14 , a standard device in vehicles normally used for drying air from an air compressor, has been configured to be put in before the injectors. The use of a 24 volt alternator(s) 12 creates higher moisture content in the gas stream, necessitating the use of air dryer 14 before the gas stream enters the injectors.
[0015] One embodiment of the present disclosure utilizes two alternators. The first alternator is for standard operations in the automobile. The second alternator sends power hydrogen generator 100 . In one embodiment, the air conditioning pump is replaced and a stock alternator is used to charge the 12 volt car battery. In this embodiment the second alternator has a voltage regulator that can be turned by hand to charge two 12 volt batteries. The 12 volt batteries were wired in series to 24 volts to power hydrogen generator 100 . This configuration allowed sufficient production of fuel to power an automobile.
[0016] FIG. 2 is a side view schematic diagram illustrating the flow of water through system 10 . Hydrolysis takes place in hydrogen generator 100 . Contained within hydrogen generator 100 is Joe cell 106 , where the hydrolysis reaction occurs. Cooling water pump 102 pumps water from hydrogen generator 100 to hydrogen agitator mixer 20 . As water flows through hydrogen agitator mixer 120 it passes through filter 104 . The filter 104 traps sludge produced during electrolysis in hydrogen generator 100 . The filter 104 may be a standard water filter used in a home setting and may be about 12″ long and 2″ wide and made from foam plastic mesh and rubber.
[0017] Filter 104 may also have a ½ inch hole down the middle of the filter for forcing air or other gases into the filter 104 . The particular diameter of the filter 104 hole may vary. Filtered water passes from the hydrogen agitator mixer 20 into the water output 124 . From water output 124 , water travels through water cooler 120 , where it is cooled by fan 122 . After passing through water cooler 120 , the water is reintroduced to hydrogen generator 100 , where it is used for hydrolysis. Related systems use additives to promote combustion of hydrogen; however, the present disclosure utilizes the sludge produced as a by-product of hydrolysis to promote combustion.
[0018] The high voltage utilized by engine system 10 created the desire for a novel method of cooling engine system 10 that improves efficiency and reduce maintenance, as shown in FIG. 2 . Engine system 10 utilizes, in one embodiment, 70 amps of power for electrolysis. This level of power causes the water to boil, which could decrease efficiency of engine system 10 if not appropriately cooled. In the present disclosure, cooling water pump(s) 102 a and 102 b , as shown in FIG. 2 , FIG. 3 , and FIG. 5 are uniquely configured to cool the engine system 10 . When the water leaves hydrogen generator 100 it goes to the filter 104 , thereby removing residue that is formed during electrolysis then passes through water cooler 120 . The cooling system of the present disclosure generally maintains temperature of the water at 120 degrees. This temperature allows for high efficiency within engine system 120 .
[0019] The cooling system to move the hot water from the hydrogen generator to the hydrogen agitator mixer to the transmission cooler can be cooled with a cooling fan or from the front of the engine.
[0020] The sludge collected on filter 104 is removed from filter 104 in the hydrogen agitator generator 20 shown in FIG. 2 . Hydrogen agitator mixer 20 includes a hydrogen inlet 138 and air intake 136 on opposite sides of T fitting 50 . The hydrogen inlet 138 is in fluid communication with hydrogen generator 100 . The air intake is connected to an air pump 186 which forces air and hydrogen down into hydrogen agitator mixer 20 .
[0021] The hydrogen generator 100 , as illustrated in FIG. 3 , is where electrolysis occurs; whereby water is converted to hydrogen and oxygen. The housing is preferably CPVC pipe because it can be threaded to provide internal access for maintenance. A coil is not necessary in one embodiment of the present disclosure. The liquid level switch 184 controls the amount of water that comes into hydrogen generator 100 for electrolysis. The liquid level switch 184 , as illustrated in FIG. 3 , is an important component of the present disclosure and works in conjunction with water fill 204 . The hydrogen generator 100 and the hydrogen agitator mixer 20 are preferably made of 4″ pcv pipe and 4″ end caps. The lines that carry the hydrogen to the injectors are made of copper to withstand the pressure and heat. The cooling lines are made from ⅜″ transparent branded line, however, they could also be made from copper line. Compression fitting can control the leaks. Shut off valves are preferably used to turn gas and hydrogen on and off, but solenoids can be used as well.
[0022] In order for the system of the present disclosure to work optimally, a liquid level switch 184 that will not burn out is important. Therefore, a standard liquid level switch was not optimal. A separate volt source was utilized to send to the switch. Here, in one embodiment, a 12 volt step down converter to 5 volts triggers a relay turning the 6 amp water pump on and off.
[0023] FIG. 3 is a cross-sectional schematic diagram showing the channels and components of engine system 10 through which flow of air and water and internal components of hydrogen agitator mixer 20 and hydrogen generator 100 . T fitting 50 is in fluid communication with the water pulled into the hydrogen agitator mixer 20 from the hydrogen generator 100 by water pump 102 b. Once air and hydrogen are forced down into the water below filter 104 hydrogen delivery tube 200 by air pump 186 , at 40 psi in the preferred embodiment although different pressures in a range close to 40 psi may also be effective, they form bubbles that remove sludge from filter 104 . Hydrogen generator water outlet 124 and hydrogen generator water inlet 126 are used for cooling hydrogen generator 100 . A certain amount of hydrogen gets trapped in with the water. The water that has hydrogen dissolved in it is released by the agitation of the mixer. Agitation occurs by gases being forced together from different lines. Engine system 10 has no shaking or mechanical mixing devices. The mixed gas in the hydrogen agitator mixer 20 goes to the injector. Air pump 186 pulls the gaseous sludge, combined with hydrogen and air, through engine system 10 contemporaneously.
[0024] In one embodiment, hydrogen generator water outlet 124 and hydrogen generator water inlet 126 are ⅜ brass male fitting. Hydrogen generator 100 has a pressure relief valve of 85 psi. Hydrogen generator 100 has a one way valve to prevent water from backing up out of the generator. The drain cock allows for drainage from hydrogen generator 100 . Around hydrogen generator 100 , high temperature silicon is used for fittings to prevent leakage. In one embodiment, to improve upon hydrogen yield, a battery configuration was utilized such that at least 70 amps are produced for electrolysis.
[0025] Joe cell 106 is installed and, instead of two tubes, three tubes increase effective electrolysis. Joe cell 106 may be wired with 10 gauge wire and incorporates three negative tubes and two positive tubes. Stainless steel screws to attach the wire to the stainless steel may be used in place of soldering. After connecting the tubes, three negative wires were attached together using a 10 gauge battery connector and the other two wires together also using a 10 gauge battery connector.
[0026] A ⅜ stainless steel screw was used after drilling two ⅜ holes through the CPVC end cap and both holes were tapped. The screws were applied through the end cap and a stainless steel nut was also utilized. The bottom end cap was filled with epoxy glue. The system of the present disclosure functions well with 24 volts.
[0027] The sludge, hydrogen and air in hydrogen agitator mixer 20 then rise to the surface of the aqueous solution in the hydrogen agitator mixer 20 whereupon they enter the gas head space which is in fluid communication with the line to the injectors. Hydrogen gas is combustible and can run the engine, however, interestingly; the engine can run on the vaporized sludge produced from filter 104 alone, after the sludge has been released from filter 104 by operation of hydrogen agitator mixer 20 ; even when engine system 10 is operated without hydrolysis. Further, the vaporized sludge increases the fuel efficiency when combined with existing fuels.
[0028] FIG. 4 shows a top view of hydrogen agitator mixer 20 . Hydrogen outlet 140 is illustrated. Low pressure switch 40 is shown. Low pressure switch 40 is normally closed and will come on and when you reach the desired pressure it will shut the air pump off; dependent upon the fuel pressure of the vehicle. Compression fitting 38 is shown. One way valves 36 a and 36 b are shown. T fitting 50 , where hydrogen and air enter hydrogen agitator mixer 20 . Shut off valves 32 a and 32 b are shown. Pressure gauge 34 is shown. In engine system 10 hydrogen generator is in the back of the vehicle.
[0029] FIG. 5 shows a schematic diagram of the wiring of engine system 10 . Relay(s) 180 are shown, along with liquid level switch 184 and cooling water pump(s) 102 a and 102 b. Also shown is air pump 186 and fan 122 . Low pressure switch 40 is illustrated along with fuse panel 190 .
[0030] Many standard automobile engines currently utilize a 12 volt system; however, in these systems the alternator is not capable of producing enough power to generate hydrogen and oxygen at a sufficient rate. To improve power production in the present disclosure, the voltage regulator was removed.
[0031] In one embodiment of the present disclosure, to solve the problem of existing 12 volt systems that will not charge a 24 volt system, a new conversion system was herein implemented. Step up convertors do exist to produce 24 volts from 12 volt systems, however, more than 24 volts is required for effective electrolysis. Therefore, a second alternator, labeled alternator 2 , was incorporated to charge the 24 volt system. For the second alternator, the voltage regulator is removed under the system of the present disclosure. This voltage regulator may have a hand-operated dial. Additionally, a voltmeter that reads at least 32 volts may be installed.
[0032] The generator is mounted preferably as close to the engine as possible, however, in alternative embodiments the generator may be mounted in the rear trunk or in the back of a truck. The alternator and the voltage regulator are mounted in the inside of vehicle. The 32 gauge voltmeter and the pressure guide are also mounted within the vehicle.
[0033] The arrangement of the alternators, as illustrated in FIG. 2 , is important to the present disclosure. The wiring for the stock alternator remains the same. Preferably, a battery extender is used in conjunction with the standard 12 volt battery for a car. This allows for addition of devices to the battery, such as the pumps of the present disclosure or additional fuse boxes.
[0034] The second alternator of the present disclosure may have, in one embodiment, leads labeled P and G, for power and ground. The power lead charges a 24 volt battery system and the G lead is for grounding, preferably with a 4 gauge wire. Alternatively, 2 gauge wire may be used. To achieve the effect of a 24 volt battery, two 12 volt marine batteries are wired in series, resulting in 24 volts. A key element of engine system 10 is having batteries in series that provide the 24 volts you need a way to recharge those batteries with an alternator or some sort of charger. You need 316 stainless steel with about an ¼ inch gap arranged neg-pos-neg-pos-neg so, two positives and three negatives. A 4 gauge wire can be used but 2 gage wire provides less voltage drop.
[0035] In the cell the wires, necessary to wire the joe cell, are 10 gauge wires. 4 gauge wires did not split the water molecules fast enough. The heat is created by the 2 gauge wires to the 10 gauge wire.
[0036] In one embodiment, a first battery has the negative side wire extending from the alternator and the positive wire to the ITHO Generator. The first battery operates as a 12 volt battery until it is wired into the second battery. After connection in series with the second battery, 24 volts are supplied.
[0037] In one embodiment, with regard to the voltage regulator the power lead connects to the first battery of the 24 volt system. An important element of the present disclosure is the configuration of the batteries and alternators. The present disclosure recognizes that connecting the 12 volt battery from a first alternator would result in excess power being returned to the system, potentially leading to burning out of onboard computers or other vehicle components.
[0038] In an alternative embodiment, for use with bigger engines, a 200 amp isolator may be used. Further, an additional hydrogen generator, or cell two, having level switches and separate Joe cells is incorporated. In this embodiment, four 12 volt marine batteries are utilized; two for the first cell and two for the second cell. In this embodiment of the present disclosure, both battery banks are charged using the 50 amp voltage regulator. In other embodiments, additional cells can yield greater amounts of hydrogen.
[0039] Injectors may be supplied by CNG Technology or Impco Technology, for placement under the stock injector. These injectors may be drilled into the exhaust manifold so that the gas being produced can be injected into the gas engine. In the present system, hydrogen is not stored.
[0040] In one embodiment of the present disclosure, a vaporizer regulator having an inlet and outlet may be utilized for the car antifreeze to heat the hydrogen while the engine is running This may be accomplished by using a vacuum valve connected to the vaporizer so the hydrogen gas can be released from the vaporizer itself From there, a connection is made to the injector rail so hydrogen gas can be injected into the exhaust manifold, thereby allowing the engine to run on hydrogen power.
[0041] In alternative embodiments of the present disclosure for use with newer vehicles, an emulator may be required. The emulator takes signals from the car's injectors and sends them to the onboard computer so the car runs smoothly. Further, the emulator ties into the oxygen sensors map sensor in a 4, 6 or 8 cylinder car.
[0042] Although exemplary embodiments have been shown and described, it will be clear to those of ordinary skill in the art that a number of changes, modifications, or alterations to the disclosure as described may be made. All such changes, modifications, and alterations should therefore be seen as within the scope of the disclosure.
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An engine system for generating hydrogen and oxygen, and a method using a by-product of electrolysis, for use in an internal combustion engine to improve efficiency and reduce emissions. The engine system has an electrolysis cell for generating hydrogen and oxygen by electrolysis of an aqueous solution, a battery as a source of power for providing electrical power to the electrolysis cell, and cooling system for maintaining the temperature of the electrolysis cell to reduce problems associated with overheating of the cell during electrolysis. The engine system traps sludge generated during hydrolysis in a filter. The sludge is released from the filter by agitation, resulting in a gas containing the sludge which is then used during combustion to improve fuel efficiency. The novel reconfiguration of existing engine parts and introduction of new features results in a less expensive, cleaner and more efficient hydrogen powered engine.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to bed covers and cover assemblies for pickup trucks. More particularly, my invention relates to a transformable cover assembly for pickup trucks that can be switched between various user selected configurations. Known prior art most relevant to this invention can be found in U.S. class 296, subclasses 100 and 165.
2. Description of the Prior Art
For several years bed covers and cover assemblies of various forms have been mounted on the beds of pickup trucks. Prior art cover assemblies, for example, can provide a covered space for human habitation. Simpler bed covers can enclose and weatherproof storage space for cargo. However, conventional bed covers and cover assemblies are subject to various limitations.
Known bed covers cannot be easily transformed into cover assemblies. On the other hand, cover assemblies are often rigid and cumbersome, and cannot easily be transformed into a simple, low profile bed cover. Utilitarian shortcomings also result as a consequence of the mounting hardware and structural linkages employed with more complex units.
Typical bed covers are made of relatively rigid material. Usually they are pivotally attached to the truck bed opposite the tailgate, for foldable positioning upon the top of the truck bed. Typically such units can be raised from the rear to allow access to the cargo space. In the closed position typical bed covers are nearly flush with the top of the truck bed, i.e., they are only a few inches greater in height than the top of truck bed. As a result precious cargo space is limited and cramped. Further, conventional bed covers must be removed or left in an awkward, open position to allow the loading of cargo taller than the top of the truck bed. This exposes the cargo to the weather. The usual bed cover is not desirable for human habitation due to the lack of interior volume and poor ventilation.
Typical cover assemblies are made of rigid material. They are fixedly mounted to the top of the truck bed with a variety of hardware mounting systems. Such cover assemblies usually comprise a front wall, opposed side walls, and a rear hatch assembly, with all four sides containing safety glass windows for rearward and lateral visibility. The roof portion of known cover assemblies is usually flush with the top of the cab of the pickup for streamlining. However, some heavier and bulkier camper inserts extend beyond the roof of the cab, and extend beyond the dimensions of the bed. When compared to simple bed covers, most cover assemblies provide a larger covered storage space. Obviously larger payloads and bulkier cargoes can be accommodated. A typical cover assembly also provides more habitable space for humans due to the greater dimensions of the structure. Creature comfort can be enhanced by the inclusion of windows within the camper structure, which can be opened for ventilation.
However, typical cover assemblies or inserts obstruct rear visibility. A simple low profile bed cover, on the other hand, usually does not obstruct the driver's rear view. Campers are difficult to attach to and detach from the truck bed, due to the sheer weight and bulk. Once removed, typical campers require a large area for off-vehicle storage. The bed cover, comparatively, is lighter in weight and requires less off-vehicle storage space.
It is therefore highly desirable to provide an improved cover assembly for the bed of a pickup truck which can be easily user-transformed from a bed cover mode to a camper mode. It is further desirable for such a transformable arrangement to overcome the utilitarian disadvantages of the prior art devices discussed above.
Typical prior art patents which show variable configuration cover assemblies for the bed of a pickup truck can be seen in a variety of prior U.S. patents. Byrd in U.S. Pat. No. 4,496,184 disclosed a flexible cover structure disposed over a plurality of frames. Benignu, Jr. in U.S. Pat. No. 5,335,960 discloses a tonneau cover which becomes a shelter roof when raised by elongated support members. Borchers in U.S. Pat. No. 5,213,390 discloses a variable configuration shelter including a relatively rigid shell that can be displaced to provide a covered lodging at the cargo carrying area.
In contrast to the prior art patents for variable configuration cover assemblies for pickup truck beds, the present invention combines the advantages of simple bed covers with those of larger cover assemblies.
SUMMARY OF THE INVENTION
The transformable cover assembly of the present invention is adapted for installation on top of a typical pickup truck bed. It can be quickly transformed between a low profile bed cover configuration, a fully expanded, cover assembly configuration, and an intermediate configuration.
The preferred cover assembly comprises a dynamic, connecting framework arranged above the pickup bed. It comprises a pair of pivotal support frames connected to mounting rails secured to the truck bed. The body of the enclosure is formed by a pair of cooperating segments, each of which, when deployed, assumes a wedge-shaped profile of generally triangular cross section. Upon full deployment of the cover assembly, the wedge-shaped halves align to form an enclosure generally in the form of a regular parallelepiped. The bottom segment is linked to the framework by suitable hinges. The top segment is hinged to an opposite end of the companion segment. Thus the cooperating segments are unfolded by the framework to form the body of the enclosure.
Flexible, generally triangular side walls are unfurled by each segment during deployment. The walls are unfolded to a deployed position in response to frame expansion. They are preferably constructed of pliable, waterproof fabric that facilitates folding and structural transformation. Visibility is enhanced by transparent, vinyl windows that are exposed when the walls are deployed. A hatch, containing a transparent rear safety glass, is pivotally deployed to form the rear of the enclosure.
Thus it is an object of this invention to provide a cover assembly for pickup trucks that presents the combined advantages of bed covers and camper shells or inserts.
Another important object is to provide a low profile, rapid deployment cover assembly for pickup trucks.
It is another object of the invention to provide a stable camper assembly that can be compactly transported in a generally flat mode.
Another object is to provide a covered cargo space for objects of different dimensions.
A related object is to provide a space for human habitation.
A still further object of my invention is to allow rapid deployment of a cover assembly from a stationary location.
Yet another object is to provide a cover assembly that is easily attachable and detachable.
Another object is to provide a cover assembly of the character described that occupies minimal storage space when detached.
These and other objects and advantages of the present invention, along with features of novelty appurtenant thereto, will appear or become apparent in the course of the following descriptive sections.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following drawings, which form a part of the specification and which are to be construed in conjunction therewith, and in which like reference numerals have been employed throughout wherever possible to indicate like parts in the various views:
FIG. 1 is a fragmentary, right side elevational view of my transformable bed cover disposed in the bed cover mode, and mounted on a conventional pickup truck in accordance with the best mode of the invention;
FIG. 2 is a fragmentary, right side elevational view similar to FIG. 1 with the transformable bed cover disposed in an intermediate transformed position partially raised at the rear;
FIG. 3 is a view similar to FIGS. 1 and 2, with the truck bed cover raised at the front to assume a transformed, shell position;
FIG. 4 is a fragmentary, perspective view showing the truck bed cover disposed in a closed, bed cover position;
FIG. 5 is a perspective view of the preferred actuator framework, showing how the framework appears when the cover assembly is disposed as in FIG. 4;
FIG. 6 is a fragmentary perspective view showing the truck bed cover disposed in a fully erected position;
FIG. 7 is a perspective view of the preferred actuator framework, showing how the framework appears when the cover assembly is disposed as in FIG. 6;
FIG. 8 is a fragmentary perspective view showing the truck bed cover in an intermediate position similar to that illustrated in FIG. 2;
FIG. 9 is a fragmentary perspective view of the actuator frame work, showing how the framework appears when the cover assembly is disposed as in FIG. 6, with portions thereof omitted for clarity;
FIG. 10 is a perspective view of the truck bed cover assembly fully deployed, disposed a transformed position similar to that shown in FIG. 3;
FIG. 11 is a fragmentary perspective view of the actuator framework, showing how the framework appears when the cover assembly is disposed as in FIG. 7;
FIG. 12 is a left side partial cross sectional along line 8--8 showing interrelationships of the deck, shroud and related mechanism in the closed position;
FIG. 13 is an enlarged, fragmentary sectional view taken generally along section line 9--9 of FIG. 4;
FIG. 14 is an enlarged, partial perspective view of a latch utilized in conjunction with the cradle bracket of FIG. 9; and
FIG. 15 is a fragmentary sectional view taken generally along section line 10--10 of FIG. 4.
DETAILED DESCRIPTION
With initial reference directed to FIGS. 1-6 of the appended drawings, a typical conventional pickup truck 12 of the type having a cab, a truck bed 14 behind the cab, which truck bed is defined by upstanding sides contiguous with the rear of the cab, and a tailgate; in which my transformable cover assembly 16 is mounted. The instant cover assembly may be deployed in the closed, "bed cover" position of FIGS. 1 and 4, or it may be fully deployed in the camper configuration of FIGS. 3 and 10. During the deployment procedure, the intermediate configuration of FIGS. 2 and 8 will be assumed, as explained hereinafter.
Preferably the deployed enclosure in the camper mode comprises stacked segments 19A and 19B (FIG. 3). Parts described hereinafter allow the apparatus to be transformed between the flat position of FIG. 1 and the stacked position of FIG. 3. Each segment 19A and 19B is generally wedge shaped. Segment 19A is elevated at the rear of the truck, and ramps downwardly. Segment 19B is complimentary with segment 19A, in effect having its tallest dimension near the cab of the truck. When deployed these twin segments unfold and stack into an arrangement generally resembling a parallelepiped. Frame elements to be described later unfold from a generally planar orientation (FIG. 5) assumed in the bed cover mode to provide skeletal support for the twin, wedge-shaped segments 19A and 19B.
The preferred cover assembly 16 (FIGS. 4, 6) comprises a compound deck 18 which, in the bed cover configuration (FIG. 1), overlies and encloses the truck bed 14. The truck bed 14 comprises a front panel 30, opposed side panels 32, and a tailgate 34. A handle travel slot 36 is located at the rear of the base frame shroud 20. The generally flat, rectangular deck 18 is operatively dynamically mounted over the truck bed by actuator framework 38 to be described hereinafter. Deck 18 preferably comprises a generally rectangular, apertured shroud 20 and a displaceable top 22. When retracted, deck 18 covers the truck bed cargo area (FIG. 1). The peripheral lip 21 of shroud 20 covers the truck cargo rail edges 15 when deck 18 is disposed as in FIG. 1. The rigid, generally planar top 22 overlies shroud 20 and normally covers the shroud opening 20A (FIG. 4) to enclose the truck bed 14. In a closed position, the outer, peripheral edge 21 of shroud 20 is positioned on top of the bed 14 with the inner perimeter of the base shroud 20 generally open to the truck bed 14. Top 22 is positioned on shroud 20, in a closed position, with the outer edge of top 22 extending beyond the inner perimeter of shroud opening 20A to complete deck 18.
In FIG. 2 the cover assembly 16 has been partially erected or transformed. Deck 18 has been lifted upwardly with respect to the rear of truck 12. Deck 18, including top 22 and shroud 20, is pivotally raised about point 25 upwardly from the truck bed 14. During this maneuver the cover assembly 16 deploys generally triangular walls 24 containing transparent vinyl windows 23. The walls are preferably made from pliable waterproof fabric that folds into or out of position as the deck 18 is raised or lowered.
In FIG. 3 deck 18 is shown in a second relative position of transformation with top 22 pivotally raised at rotation point 27 upwardly from the shroud 20 to a position wherein the deck 18 is coplanar with the roof line of the cab of the truck extended. As the top is raised relative to deck 18, pliable, waterproof walls 26 foldably deploy similarly to walls 24. Walls 26 comprise transparent, vinyl windows 23A. A similar pliable waterproof fabric front wall 28 (FIGS. 3, 10) unfolds a transparent vinyl window 23B.
With reference now to FIGS. 5, 7, 9, and 11, the preferred actuator framework 38 is utilized to "unfold" and thus control and deploy the apparatus. Framework 38 comprises a transverse crosspiece 40 extending between parallel base rails 42 that are attached above bed 14 to the truck side panels 32 by clamps 43. Opposed side rails 44 are pivotally attached to the crosspiece 40 by offset brackets 46. A transversely extending, generally C-shaped support 48 is pivotally attached to the crosspiece 40 by brackets 50. Support 48 comprises a central sleeve 56 pivotally secured with roller wheels 58 attached at each end of sleeve 56. Sleeve 56 is slidably captivated within a latch actuator assembly 60 which is attached to the underside of top 22.
An extendible shaft 62 comprising an outer shaft 63 slidably, coaxially receives inner shaft 62A (FIG. 9) that is attached to sleeve 56. The aft end of outer shaft 63 detachably connects to holder 64 which is attached to the underside of top 22 (FIG. 5). When activated, shaft 62 elongates and pivots support 48 and sleeve 56 from the generally horizontal position of FIG. 5 to the generally vertical, deployed position of FIG. 11.
A rear hatch frame 52 is pivotally attached to the side wall rails 44 by carriage bolts 54 that penetrate legs 52A. The transversely oriented hatch frame 52 suspends a generally rectangular, deployable hatch 66 (FIGS. 8, 10) controlled by a pivoted handle 68. A rubber weatherproofing flap 70 is attached to the hatch bottom edge. A safety glass rear panel 72 is secured by hatch 66. The upper ends of legs 52A of hatch 52 are slidably coupled to guide tracks 74 (FIG. 5) which are attached to the underside of shroud 20.
With reference to FIG. 6, cover assembly 16 is shown in the bed cover mode raised to a twenty-degree angle. Shroud 20 is hingedly attached to the forward crosspiece 40 at the bed front, immediately in back of the cab. The cover assembly 16 is raised at the rear, being assisted by hydraulic struts 76. The crosspiece 40 and the base rails 42 (FIG. 7) remain attached to the side panels 32 of truck bed 14 by clamps 43.
FIG. 8 shows the cover assembly 16 disposed in an intermediate position, assumed when transforming from a bed cover mode to a camper mode. Preferably cover assembly 16 is lowered from the twenty degree angle position shown in FIG. 6 to an angle of fifteen degrees. Hatch frame 52 is shown in a lowered position with the hatch 66 in an open position supported by back hydraulic struts 80. Rails 44 are in a lowered position, with the partial lower walls 24 extended to an open position from a closed, folded position. Snap buttons 81 attached to the rear edges of walls 24 are connectable to snap buttons 82 on hatch frame legs 52A. The extendible shaft 62 projects outwardly from the rear of the truck, passing through the space voided by the displaced raised hatch 66.
The upper edge of the side walls 24 (FIG. 8) are attached to the lower hangers 84 (FIG. 9). The lower side hangers 84 are attached to the underside of shroud 20. Guide tracks 74 are attached to the underside of shroud 20. The upper ends of struts 76 are pivotally attached to the inner perimeter of shroud 20. The lowermost ends of struts 76 are pivotally attached to rails 42.
As best illustrated in FIG. 10, top 22 is hingedly attached at the rear to shroud 20, allowing top 22 to pivot upward at the front to a fifteen-degree angle to reach the second transformed position establishing the camper mode (FIGS. 3, 10). Top 22 is assisted by upper hydraulic struts 86 when fully deployed. Support 48 is raised to a generally vertical position with the front wall 28 and partial upper walls 26 extended to an open position from a closed, folded position. The vertical outside edges of the front wall 28 are attached (sewn) to the vertical forward edges of the upper partial wall 26.
Front hanger 88 provides support for the front wall 28. The upper edges of side walls 26 (i.e., FIG. 3) are attached to the upper hangers 90 (FIG. 11). The lower edges of walls 26, 28 are attached to the inner perimeter of shroud 20. The front hanger 88 and the upper hangers 90 are attached to the underside of top 22. The upper ends of hydraulic struts 86 are pivotally attached to the upper side hangers 90. The lower ends of the upper hydraulic struts 86 are pivotally attached to the inner perimeter of shroud 20.
With reference now to FIG. 12, rails 44 are of generally L-shaped cross section. The base 92 of each rail rests upon a portion of gasket seal 98 attached to a sleeve 94. The sleeve 94 is captivated within a fabric loop 96 sewn into the lower edge of wall 24 before attachment to the gasket seal 98. Base 98 has weather-stripping 114 attached at both its bottom and top to provide an air- and watertight seal when the, gasket seal 98 is lowered into contact with side panels 32.
The rails 44 are pivotally attached to leg 52A by carriage bolt 54. Leg 52A pivots about bolt 54 and tubular spacer 100 that is coaxial with bolt 54. The portion of the carriage bolt 54, not contained within the nylon tube 100, passes through holes in the end of the side wall rails 44. The carriage bolt 54 attaches to a fastener 102 attached to the outside edge of the gasket seal 98. A cradle bracket 104 attached to rail 42 has a groove in its top seating nylon tube 100. A catch pin 106 is attached to the cradle bracket 104. A turn latch 108 is pivotally attached to the end of carriage bolt 54 inboard of the cradle bracket 104. Latch 108 projecting from the inside edge of leg 52A is connected to the inside edge of leg 52A and pivots in line. Guide pin 110 (FIG. 12) attached to the top of frame legs 52A extends into a slot 111 in the guide 74 (FIG. 13). A raised lip 112 formed along the inner perimeter of shroud 20 dams water. Edge trim weather-stripping 114 is attached at the outer perimeter of shroud 20 and top 22 to form a watertight seal when deck 18 is in the closed position.
As shown in FIG. 13, rear hinge 116 pivotally attaches the shroud 20 to top 22. Handle 68 extends through travel slot 36. The handle 68 is splined to shaft 118 which is attached to the bottom of the hatch 66. Shaft 118 reaches retainer rods 120 that are extendible and retractable by turning handle 68. The retainer rods 120 are retained in slots 122 cut through slot brackets 124, which are attached to the lower inside of the frame legs 52A. Retainer rods 120 lock the apparatus when disposed in slots 122; when withdrawn in response to handle rotation, the hatch 66 may be pivotally raised from hatch frame 52. The ends of the retainer rods 120 will extend an inch further outboard from the first extended position to pass through slots 126 within the cradle bracket 104, as shown in FIG. 14. This allows the retaining rods 120 to have a secondary function of securing the rear of the cover assembly 16 to the truck bed 14 while the cover assembly 16 is disposed in the closed position of FIG. 4.
While the cover assembly 16 is closed, turn latch 108 (FIGS. 9, 9A) is centered within retainer bracket 128 which is attached to the inside surface of the base frame shroud 20 adjacent to the tailgate 34. Holes 130 bored in the retainer bracket 128 line up with a notch in the turn latch 108 to allow insertion of retaining pin 132 attaching the bottom of legs 52A to shroud 20. This allows the framework 38 and the pliable fabric walls 24, 26, and 28, with the exception of the side base rails 42 attached to the side panels 32 of the truck bed 14, to be raised with the deck 18 as shown in FIG. 6 and 7.
In FIG. 15 shroud 20 is shown pivotally attached to the forward crosspiece 40 by hinge 134. The latch actuator assembly 60 comprises a guide 136, an actuator arm 138, a connecting rod 140, and a latch 142. Guide 136 is attached to the underside of top 22. The top of support 48 is received within sleeve tube 56, passing through a guide slot 144 in guide 136. The actuator arm 138 is pivotally attached to guide 136. The connecting rod 140 is pivotally attached to the actuator arm 138, at one end, and passes through an opening in the front hanger 88 to pivotally attach to the latch 142 at the opposite end. The latch 142 is pivotally attached to a latch bracket 146 which is connected to the front hanger member 88. A catch 148 connected to the front of shroud 20 is selectively engaged by latch 142. A stop pad 150 is attached to top 22 above the actuator arm 138.
Operation
1. Transformation from Bed Cover Mode to Intermediate Mode
With the cover assembly 16 in a closed position, as shown in FIG. 4, the handle 68 is rotated retracting retainer rods 128 from slots 126 within cradle bracket 104 (FIG. 14). The cover assembly is pivotally raised at the rear, automatically, by hydraulic struts 76. The cover assembly 16 is now disposed in a fully erect position of twenty degrees, as shown in FIG. 6. At this point, the retainer pins 132 are retracted from holes 130 in retainer brackets 128 attached to the inside of the shroud 20 at the rear (FIG. 13). The latches 108, attached to the bottom of the frame legs 52A of the hatch frame 52, are freed of attachment within the retainer brackets 128 with the extraction of pins 132. The hatch frame 52 can now be lowered via handle 68 with handle shaft 118 passing through handle slot 36 in the rear of shroud 20. The top of the hatch frame 52 is captivated within and guided rearwardly along guide member 74 by pins 110, attached to top of frame legs 52A, sliding through guide slot 111 in the guide 74 (FIGS. 12, 13). The carriage bolt 54 contained within tube 100 pivotally attaches the bottom of frame legs 52A and the side rails 44 (FIG. 12) allowing for simultaneous lowering of both frame members with the forward ends of the side rails 44 lowering pivotally at offset bracket 46 (FIG. 15).
The hatch frame 52 is lowered until the nylon tube 100 sets in a groove on top of the cradle bracket 104. The hatch 66 is detached from the hatch frame 52 by rotating handle 68 which retracts retainer rods 120 from slots 122 within slot brackets 124 attached to the bottom of the frame legs 52A on the inside, (FIG. 13). Hatch 66 is raised pivotally, assisted by struts 80 (FIG. 8). The top of hatch frame 52 is pulled rearwardly, via handle 68 attached to hatch 66, (FIG. 8), until movement is obstructed by pins 110, connected to the top of the frame legs 52A, contacting the aft end of slot 111 within guide member 74, as shown in FIG. 13. The latch 108, connected to the bottom of frame leg 52A, has rotated about the nylon tube 100 seated in the groove atop the cradle bracket 104 to a position where catch pin 106, attached to cradle bracket 104, is captured within latch 108 (FIG. 14). The partial lower walls 24 have been extended to an open position from a closed, folded position by the simultaneous lowering of the side rails 44. Snap caps 81, attached to the rear edges of the partial side walls 24, are connected to the snap buttons 82 attached to the frame legs 52A to seal the rear corners from elements of weather (FIG. 6, 9A).
Extendible shaft 62 is detached from shaft holder 64 and lowered at the rear. Outer shaft 63 is loosened from a locked position containing inner shaft 62A by twisting shaft 63 clockwise about inner shaft 62A. The outer shaft 63 is pulled rearward exposing inner shaft 62A until reaching an internal stop at the aft end of inner shaft 62A and the forward end of outer shaft 63. Outer shaft 63 is relocked to inner shaft 62A by twisting outer shaft 63 counterclockwise about inner shaft 62A until tight. The outer shaft 63 has now been extended rearward almost the entire length of the contained inner shaft 62A and extends through the space voided by the raised hatch 66 (FIGS. 6, 9A).
2. Transformation from Intermediate Mode to Camper Mode
The extendible shaft 62 is now pushed forward manually to begin raising support 48. The tube 56 housing the top of support 48 starts to travel forward along slot 144 in guide 136. Tube 56 is directed slightly upward along slot 144 to engage actuator arm 138 (FIG. 15). Actuator arm 138 is forced upward by continued forward travel of tube 56 along slot 144. The connecting rod 140, pivotally attached to the actuator arm 138, is simultaneously raised and pushed forward by upward rotation of actuator arm 138. When tube 56 reaches the end of the short upward travel span of the slot 144, the actuator arm 138 is fully raised and the connecting rod 140, pivotally attached to latch 142, has forced latch 142 to pivot about latch bracket 146 disconnecting latch 142 from catch 148. The top 22 has been detached from shroud 20 at the precise moment that the roller wheels 58, attached to the top of support 48 at the ends of tube 56, have risen to contact the underside of the top 22. Top 22 is now acted upon by hydraulic struts 86, (FIG. 10,11), and the support 48 is pivotally raised at brackets 50 (FIG. 15), with roller wheels 58 maintaining a centered position of tube 56 moving through slot 144. The aft end of shaft 62 is supported and guided forward manually exerting no force as the support 48 pivots to an upright position. The top 22 is fully raised by hydraulic struts 86 when the tube 56 contacts the forward end of slot 144 (FIG. 15). The rearward end of the outer shaft 63 of shaft 62 is now attached to the inside top of hatch frame 52,(FIG. 11). Shaft 62 is now utilized as frame member between the hatch frame 52 and the support 48 and also prevents the shaft 62 from vibrating loose from the locked position between the outer shaft 63 and the inner shaft 62A.
The front wall 28 along with the partial upper side walls 26 have been automatically extended to an open position from a closed, folded position by the process of transformation. The hatch 66 is lowered and secured to the hatch frame 52 by rotating handle 68 which extends retainer rods 120 to a primary extended position with retainer rods passing through slots 122 in slot bracket 124 (FIG. 13). The transparent vinyl windows 23, contained within the partial lower walls 24, can be unzipped to allow for ventilation.
3. Transformation Back from Camper Mode to Bed Cover Mode
The hatch 66 is detached from the hatch frame 52 by twisting handle 68 which retracts retainer rods 120 from slots 122 in slot bracket 124 (FIG. 13). The hatch 66 is pivotally raised to an open position assisted by struts 80 (FIG. 8). The Shaft 62 is detached from hatch frame 52. Shaft 62 is pulled rearwardly causing the support 48 to lower as the tube 56, housing it at the top, travels back through slot 144 in guide 136, FIG. 15. The struts 86 start to compress and the front wall 28 with the partial upper walls 26 start to collapse as the top 22 is lowered by attachment to the guide 136. The shaft 62 is pulled back until the tube 56 contacts the rear of slot 144 in guide 136 (FIG. 15). The tube 56 has pivoted the back of the actuator arm 138, with over-slam dampened by rubber stop pad 150 attached to underside of top 22, causing the front of the actuator arm 138 to lower. The connecting rod 140 is retracted by the pivotal movement of the actuator arm 138 reconnecting the latch 142 to the catch 148. The support 48 has lowered to a closed position and the top 22 is reattached to the shroud 20 in a closed position, as shown in FIG. 8. The front wall 28 and the partial walls 26 have been automatically returned to a closed folded position and the hydraulic struts 76 are fully compressed. The outer shaft 63 of the extendible shaft 62 is now turned clockwise to loosen locked position to inner shaft 62A. Outer shaft 63 is retracted over inner shaft 62A until reaching an internal stop and outer shaft 63 is twisted counterclockwise about inner shaft 62A until locked. Outer shaft 62 is reattached to shaft holder 64 (FIG. 13).
Snap caps 81, attached to the rear edges of the partial lower walls 24, are detached from the snap buttons 82 which are attached to the frame legs 52A of the hatch frame 52.
The hatch 66 is closed and secured to hatch frame 52 by twisting handle 68. The deck 18 is manually lowered at the rear which causes hatch frame 52 to pivot forward at the top. With shaft 62 in a retracted position, the pins 110 attached to the top of frame legs 52A of hatch frame 52 are free to travel forward through slots 111 in guide 74 (FIG. 12,13). As the deck 18 is lowered, the bottom of hatch frame 52 pivots on the nylon tube 100, housing carriage bolt 54, setting in the groove on top of cradle bracket 104. The hydraulic struts 76 start to compress and the partial lower walls 24 start to collapse with the handle shaft 118 fitting into the handle slot 32, at the rear of shroud 20, as the deck 18 is lowered until contacting the top of the truck bed 14 (FIG. 4). At this time the cover assembly is released to be raised pivotally at the rear, acted upon by the hydraulic struts 76 expanding, to a twenty-degree angle as shown in FIG. 6. The hatch frame 52 is in a folded position (FIG. 7) and the partial lower walls 24 are returned to a closed, folded position. The latches 108, attached to the bottom of the frame legs 52A, have rotated in line with the hatch frame 52 to position in line with the holes 130 in the retainer bracket 128 attached to the inside at the rear of shroud 20 (FIG. 13). Pins 132 can now be reinserted in holes 138 to capture latches 108 within the retainer bracket 128 thereby securing the hatch frame 52 and the rails 44, due to pivotal attachment between the two, to the shroud 20. The deck 18 is manually lowered again to the point at which it contacts the top of the truck bed 14. Handle 68 is rotated extending the retainer rods 120 to a secondary extended position passing through slots 126 in the cradle bracket 104, as shown in FIG. 14, securing the cover assembly 16 to the truck bed 14.
From the foregoing, it will be seen that this invention is one well adapted to obtain all the ends and objects herein set forth, together with other advantages which are inherent to the structure.
It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claim.
As many possible embodiments may be made of the invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.
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A transformable cover assembly for pickup trucks is user switchable between a low profile, bed cover configuration and a fully deployed, camper configuration. The apparatus unfolds from a planar orientation into a pair of cooperating, stacked, generally wedge-shaped segments. The segments are complementary; the stacked wedge-shaped segments form an inhabitable enclosure in the general form of a parallelepiped when erected. A planar deck that is foldably deployed comprises a top that ultimately covers the upper segment, and a shroud that unfolds to form a border between the adjacent, deployed segments. A foldable framework comprising a plurality of cooperating members enables foldable transformation. As the assembly deploys it unfurls pliable, generally triangular walls at the segment sides.
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BACKGROUND OF THE INVENTION
The present invention relates to a method and system of displaying hardware products, and particularly to such a system involving display board panels and the like in a wall mounted environment or on a display rack.
It has become a common practice in the merchandising of hardware items or products to utilize display racks as part of point of sale merchandising techniques. Such racks often take the form of two-dimensional wall units or so-called floor merchandisers, the latter comprising a three-dimensional arrangement, such as, for example, a three or four sided rotatable rack. What this merchandising practice generally involves is the deplopment of the hardware items on peg board panels by inserting hooks of one kind or another through apertures which are generally arrayed, in an orderly way on the display board, such that the hardware items can be easily mounted or hung on the hooks. In order to guide the placement of the items in setting up the display, and to serve eventually as a means of furnishing information to the prospective customer, "out-of-stock" cards are generally suitably spaced from each other and in near abutting relationship to the display board panels. These "out-of-stock" cards are carried by the hooks, the hooks being inserted through apertures provided in the cards.
Although conventional systems for displaying hardware products in the aforedescribed way have gained acceptance and are widely used, a very severe drawback to the merchandising of hardware in this manner is that the jobber or retailer finds that he does not wat to spend the significant amount of time normally consumed in setting up the display system. For example, it quite often takes two and one-half hours to set up a complete hardware display system involving a four-sided display rack. This time consumption is partly accounted for by the fact that there is a tendency not to place the appropriate hooks into the display board panel at sufficiently close spacing with respect to adjacent hooks so that oftentimes space is lost on the panel. Consequently, the jobber or retailer has to go back and re-do a particular panel and the whole process can be very frustrating. In order to assist the jobber or retailer a schematic or general layout of the display system is sometimes furnished; that is to say, a layout which shows how the particular out-of-stock cards, as well as trays and booklet containers are to be set up on the panel. A fundamental difficulty with the use of the schematic, however, is that quite often the card numbers include digits that are very similar, such that these digits are sometimes mentally reversed, and the result is that the cards are not placed in their proper locations.
Accordingly, it is a primary object of the present invention to solve the aforenoted drawbacks and difficulties and to facilitate close, neat spacing in the placement of various indicia-bearing members on a hardware display panel.
Another object is to avoid the consumption of substantial amounts of time in setting up a complete hardware display. With respect to the time period involved, the system of the present invention is effective to reduce that period from two and one-half hours to about forty minutes.
SUMMARY OF THE INVENTION
A key feature of the present invention resides in the attainment of versatility and flexibility in the setting up of a hardware display system. Thus, in accordance with the present invention, one is permitted to up-date the display by shifting or changing the out-of-stock cards forming part of the display or even to shift or change trays or booklet-holding containers and the like as different combinations of hardware products are modified or changed.
The above-noted feature contrasts with methods that have sometimes been adopted to solve the aforenoted drawbacks, namely, expedients such as the use of pressure sensitive adhesive labels, or the use of silk screening or other techniques, to affix the required indicia on the panel. Such techniques are not regarded as useful solutions because in both cases, there is great difficulty in removing the indicia in the event that the particular hardware product in a given location is to be changed; that is, when another hardware item is to be substituted in that space where the indicia has already been affixed.
Briefly described, the present invention provides a display system and a technique associated with that system which makes for very fast setting up of a particular hardware display. This results from the provision of the present invention which comprises a carrier sheet adapted to be placed against a particular panel member. This carrier sheet constitutes an integrated arrangement of the indicia-bearing out-of-stock cards, for example, which are connected by a webbing. The indicia-bearing cards have slit-like perforations along their borders with the webbing and they carry apertures which are precisely located by prearrangement so that they will line up with predetermined corresponding apertures in the panel member. As a result, the hooks on which the hardware products are to be placed can be readily inserted through both sets of apertures, that is, through those formed in the cards and into those formed in an array on the panel. Once the carrier sheet has been placed against the panel member and has been properly indexed, that is, the edges of the carrier sheet have been set against the edges of the assigned panel member, and once the hooks have been inserted, then the webbing can be readily removed because of the slit-like perforations. Consequently, in very short order, each of the appropriate out-of-stock cards has been placed in the discrete location where it belongs, and the entire group of appropriate hooks can be inserted into the proper panel apertures. All that remains thereafter is to place or to hang the particular hardware products in accordance with the guidance furnished by the already mounted cards.
Other and further objects, advantages and features of the present invention will be understood by reference to the following specification in conjunction with the annexed drawing, wherein like parts have been given like numbers.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a plan view of a carrier sheet in accordance with a preferred embodiment of the present invention;
FIG. 2 is a perspective view of a floor merchandiser in the form of a three-dimensional display apparatus which incorporates carrier sheets like the one previously illustrated in FIG. 1;
FIG. 3 is another perspective fragmentary view of the display apparatus of FIG. 2, and particularly illustrating the removal of the webbing which is normally connected between the indicia-bearing cards, but which is capable of being readily removed;
FIG. 4 is a horizontal sectional view, taken on the line 4--4 of FIG. 3, illustrating indicia-bearing cards in abutting relationship with the display panels;
FIG. 5 is a perspective view of the display apparatus, particularly illustrating the placement of a variety of hardware products for display purposes in the locations indicated by the respective indicia-bearing cards;
FIG. 6 is a horizontal sectional view, taken on the line 6--6 of FIG. 5, of a fragment of a display panel, illustrating several indicia-bearing cards and the hardware packages associated therewith;
FIG. 7 is a vertical sectional view, taken on the line 7--7 of FIG. 6, illustrating the details of the mounting of the hardware packages.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring now to the figures which illustrate the preferred embodiment of the hardware display system of the invention, it will be first noted that in FIG. 1 a carrier sheet 10 is illustrated. This carrier sheet, in accordance with a primary feature of the present invention, constitutes an integrated arrangement of indicia-bearing members or cards 12 which serve eventually to identify which particular hardware product is to be placed in a given location on the display apparatus. By the term "integrated arrangement" is meant the arrangement of the individual cards 12 in such spaced relationship as to indicate where particular hardware products are to be located, including the provision of a connecting webbing 14 which connects all of the cards in a particular array as illustrated in FIG. 1. Discrete pairs of apertures 16 are usually provided for each of cards 12, these apertures being so located that they match with corresponding pairs of apertures in display board panels. Slit-like perforations 18 extend completely around the periphery of each of the cards 12.
Referring now to FIG. 2, a complete display apparatus 20 is therein illustrated, this display apparatus being a more or less conventional, three-dimensional rack or display system comprising pairs of panels or panel members 22 on each side of the four sides of a framework 23 which is carried on a supporting pedestal 24 and is rotatable on an upstanding shaft 25.
In particular it will be noted that the given carrier sheet 10 of FIG. 1 is again illustrated in FIG. 2, being therein identified as sheet 10A. Moreover, sheet 10A is shown as having been placed in abutting relationship with the upper panel member 22 which partly forms one side of the display apparatus 20. Of course, it will be appreciated that rather than two panel members per side, a single panel member 22 co-extensive with that side, or a greater number of members, could be provided. In setting up the hardware display, the carrier sheet 10A is placed against upper panel member 22 with the edges of each appropriately aligned. Then several hooks designated 26 are inserted through respective pairs of apertures 27 which are provided in an orderly spaced array in panel members 22.
The particular hooks 26 illustrated in FIG. 2 are termed safety or butterfly hooks, which are provided with double prongs. These are often employed in connection with conventional hardware display apparatus. However, the system of the present invention envisions that a variety of other types or kinds of hooks, such as straight hooks and the like, can be employed in the event that somewhat different hardware items from those specifically illustated are to be displayed.
Accordingly, although the particular carrier sheet 10A shown mounted to the upper panel in FIG. 2 is constituted essentially of a plurality of indicia-bearing cards 12 and interconnecting webbing 14, it will be understood that it is also a common arrangement in well-known hardware displays to devote specific spaces for trays designed to hold bottles or cans of liquids or the like. Such trays are fashioned with integral hooks that can be inserted at appropriate blank spaces formed in the carrier sheet and thence can be inserted into apertures in panel members 22. Thus, the present invention contemplates that other similar carrier sheets, such as the sheet 10B, shown in indexed relationship with one of the lower panel members 22 in FIG. 2, would have such a format, whereby trays, such as tray 28 seen in phantom outline, would be readily mounted. In addition to trays, brochure containers or holders can be accomodated by providing other blank spaces in a carrier sheet indicating positioning of holders along dotted lines at which the pressure sensative backing on such holders can be affixed into the display panel.
It will be appreciated that all the panel members 22 are simply fitted together on the framework 23 of the display rack by appropriate horizontal retainer strips 30. These panel members are typically constituted of pressed wood, although it is also common to manufacture them from plastic material.
Referring now to FIG. 3, it will be understood that when any of the carrier sheets, such as 10A, has been mounted on a panel and the necessary hooks for each have been inserted, the webbing 14 is readily removed by simply tearing along the slitted perforation lines (FIG. 1) formed at the periphery of the cards 12. In FIG. 3 this process of removing the webbing is illustrated as just having begun. Eventually, as seen in FIG. 5, all of the webbing has been removed and a number of hardware items in packages 32 are seen as having been mounted on the hooks 26. These hooks are securely held in the panel members 22 by reason of the several successive right-angle bends 34 formed in the hooks.
Similar mounting of other hardware items is effectuated on each of the other panel members forming the other sides of the display apparatus. As indicated previously with reference to the lower panel member 10B in FIG. 2, a variety of bottles and cans are to be placed in tray 28 which is mounted at the bottom of that panel member.
What has been disclosed is a unique method and system for displaying hardware products so as to make extremely efficient the disposition of the products in appropriate places on display panels, and particularly to cut down the time normally consumed in setting up a point of sale hardware display. In accordance with the system, indicia-bearing, out-of-stock, cards which guide the placement of the hardware products in setting up the entire display can be quickly deployed in their proper locations by reason of the simple removal of a webbing which interconnects with discrete areas at which the cards are located on a carrier sheet.
While there has been shown and described what is considered at present to be the preferred embodiment of the present invention, it will be appreciated by those skilled in the art that modifications of such embodiment may be made. It is therefore desired that the invention not be limited to this embodiment, and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.
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A method and system for displaying hardware items so as to facilitate the disposition of the items or products in appropriate places on panels in a time period much shorter than is conventionally encountered.
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BACKGROUND OF THE INVENTION
The instant invention relates generally to toilet tanks, and more particularly, to a semi-flush kit.
Numerous selective flush devices have been provided in the prior art that are adapted to regulate water discharge from toilet tanks. For example, U.S. Pat. Nos. 4,620,331 of Sagucio, 4,504,984 of Burns, and 4,483,204 of Troeh, all are illustrative of such prior art. While these units may be suitable for the particular purpose to which they address, they would not be as suitable for the purpose of the present invention as hereafter described. A primary object of the present invention is to provide a semi-flush kit that will overcome the shortcomings of the prior art devices.
Another object is to provide a semi-flush kit that will be of such design, as to independently flush a selective quantity of water from a toilet tank as desired for water conservation.
An additional object is to provide a semi-flush kit that will be adapted for employment with a simple high buoyancy flush valve that is probably the most common in the art.
A further object is to provide a semi-flush kit that is simple and easy to use, and and can be installed by the home owner.
A still further object is to provide a semi-flush kit that is economical in cost to manufacture.
Further objects of the invention will appear as the description proceeds.
To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only and that changes may be made in the specific construction illustrated and described within the scope of the appended claims.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The figures in the drawings are briefly described as follows:
FIG. 1 is a fragmentary diagrammatic front elevational view of the invention installed in a toilet tank, with the operating handle shown in phantom;
FIG. 2 is a fragmentary diagrammatic top plan view of the invention with cords and flush valve shown in phantom;
FIG. 3 is a diagrammatic side elevational view taken along line 3--3 of FIG. 1 illustrating different water levels in phantom;
FIG. 4 is a greatly enlarged diagrammatic fragmentary view of a portion of FIG. 3, showing the mechanism in greater detail;
FIG. 5 is an enlarged isometric view of the thumb pressure clip for use on the rod of the invention; and
FIG. 6 is an enlarged isometric diagrammatic view of the float locking device per se with the controlled float shown in phantom.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now descriptively to the drawings, in which like reference characters denote like elements throughout the several views, a kit 10 is shown to include a frame 12 with vertical guide members 14 that are positioned on the bottom inside surface of a toilet tank 16. A first float 18 is provided and guided within one side of the frame 12, for controlling full water discharge of both water levels down to level 20, from the discharge pipe 22 by the lifting of the discharge valve 24 from its seat 26. Stabilizing side members 28 are secured between sides of frame 12 and the inside side surfaces of tank 16, and a second float 30 guided in the other side of the frame 12, controls the semi-flush down to water level 32, by a separate lifting of discharge valve 24.
A rod 34 is adjustably slideably secured in second float 30 that is fastened to a cord 36 by its eye 38, and cord 36 also extends through the bottom guide opening 40 of frame 12 and through one of the guide openings 42 in the bottom center of frame 12, where it is secured to an eye 42 of the discharge valve 24, for unseating valve 24 to discharge water. A second cord 46 is secured to a top eye 48 of rod 34 at one end and is guided through guide opening 50 through the upper end of frame 12, and the other end of cord 46 is fastened to an eye 52 of one side of rod 54 secured through shaft 56 of hand lever 58. A spring clip 60 of conventional design is fixedly secured to a bracket 62 that is fastened fixedly to the top of second float 30, and enables the height of second float 30 to be adjustable for controlling the water level 32 in toilet tank 16.
One end of a third cord 64 is secured to an eye 66 of the first float 18 and the other end of third cord 64 extends through guide opening 68 in the top of frame 12 and is secured to second eye 52 of the other side of rod 54. Cord 64 provides for lifting first float 18 to fully discharge the water at all levels and a rod 70 is fixedly secured in first float 18 and an eye 72 at its bottom has a fourth cord 74 secured thereto, that is guided through guide opening 76, and its other end is secured to eye 44 of valve 24 for water discharge of the water down to level 20. A bell shaped stop member 78 is fixedly secured to the bottom of first float 18 and receives the rod 70, and a second bell shaped stop member 80 is spaced from the upper stop member 78 and an end of a third-float lever rod 82 is freely received between the bell shaped members 78 and 80, for a purpose which hereinafter be described.
A small third-float 84 is fixedly secured to the other end of lever rod 82 and a bracket 86 is fixedly secured to the bottom surface of lever rod 82 and a pivot rod 88 is secured fixedly in bracket 86 and the ends of rod 88 are pivotally received in a pair of the guide members 14. This small float 84 and lever rod 82 combination, is a locking device and serves to prevent first float 18 from rising when second float 30 has been activated.
In operation when hand lever 58 is pulled down, the rod 54 pivots and pulls the cord 64 that lifts first float 18 that pulls cord 74 and lifts flush valve 24 from its seat 26, which causes a conventional full flush of water to be effected.
When the hand lever 58 is pulled upward, the rod 54 pivots in the opposite direction and pulls cord 46 which lifts the second float 30 and causes cord 36 to lift flush valve 24 from its seat 26 and cause a semi-flush of water. When the first float 18 is activated, the second float 30 does not require the locking device of the combination of small float 84 and its lever rod 82, because second float 30 will float freely with no adverse effect.
However, when the flush of water is under the control of second float 30, first float 18 must be held in place, or the valve 24 would be held open by first float 18 when it should have been closed as second float 30 reseated. This is because if locking device of the combination of small float 84 and its lever rod 82, were not employed as soon as valve 24 was upset by pulling on cord 36, than the lessening of force upon cord 74 would cause float 18 to also be released rendering the system inoperative.
The upthrust arising from the buoyancy of float 84 exerts a net force upwards pivoting the end of lever rod 82 received between the bell shaped members 78 and 80 against bell shaped member 80 urging the bell shaped member down, retaining the float 18 in place.
As the float 18 is only raised a short distance sufficient to raise valve 44, when cord 64 is pulled, the end 70 of lever 82 remains located between the bell-shaped members 78 and 80 which gently guide the end 70 during return of the float 18 as the water level drops with progressive pivotal movement of the lever 82 back to the original position indicated in FIG. 3.
While certain novel features of this invention have been shown and described and are pointed out in the annexed claims, it will be understood that various omissions, substitutions and changes in the forms and details of the device illustrated and in its operation can be made by those skilled in the art without departing from the spirit of the invention.
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This semi-flush kit is designed for employment with a simple high buoyancy flush valve toilet tanks. Primarily, it consists of two main floats and each are controlled by a right and left rotation of a toilet tank operator's handle. One float of the combination controls a pre-determined lower water level in the tank, and the other controls a second and higher level of water in the tank that may be discharged as desired.
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BACKGROUND OF THE INVENTION
The present invention relates to a power check meter, and in particular to a power check meter with improved data transmission characteristics.
Some electrical power customers tap the electrical power line routed to their residence or business at a location prior to their power meter in order to steal electrical power from the utility. To reduce the theft of electrical power many utilities use a portable kilowatt-hour check meter connected to the incoming power line of a suspected dishonest customer to monitor the customer's power usage. The portable check meter is normally installed high on the power pole near the location that the customer's line connects to the utility's main power line. By installing the portable check meter in such a location it is difficult for the customer to tap the incoming line prior to the portable check meter. The utility compares the recorded power usage from both the power meter and the portable check meter during the same time period and notes any difference. If the measurements are significantly different then the utility has confirmed its suspicions and obtained proof that electrical power has been stolen by the customer. The utility then takes corrective measures to ensure that the customer thereafter refrains from stealing electrical power.
Customers that steal electrical power are paranoid of being caught and may notice the utility employees installing the portable check meter on the pole near their location. If the customer notices utility employees installing such equipment, the customer will typically refrain from stealing power for a period of time. During such a time the utility will not be able to detect the theft of power. Traditionally, in order to monitor the customer's power usage, utility employees were required to be in close proximity to the portable check meter's display indicating power usage. This required a utility employee to climb the pole which may alert dishonest customers that their power usage is being monitored and cause the customer to refrain from stealing power until they are confident that their power usage is not being monitored. In addition, it is frequently dangerous for utility employees to be near such dishonest customers, especially if they are involved in illegal drug activities.
In order to alleviate the need for utility employees to be within several feet of the traditional portable check meter to read the power usage, some portable check meters include a radio-frequency transmitter that periodically transmits the power usage. The utility employee uses a radio-frequency receiver to receive and display the transmitted power usage. However, the radio-frequency receiver must still be within approximately 100 to 300 feet to receive the power usage. Accordingly, the utility employee must still get close to the customer which may inadvertently alert the customer that they are being monitored. Also, this may place the utility employee in a dangerous situation. In addition, this requires the utility employee to drive to the vicinity of the transmitter requiring significant time and expense. Further, the utility must obtain a specialized receiver to receive the power usage at additional expense. Such a system is available from Universal Protection Corporation of Atlanta, Ga., known as CMI Diversion Check Meter System.
An alternative portable check meter available from Universal Protection Corporation of Atlanta, Ga., sold under the name CPS I Cellular Phone System, further includes a cellular phone link. A radio-frequency transmitter is used to transmit power usage from the portable check meter to a radio-frequency receiver located in a separate housing. The radio-frequency receiver receives the power usage and in response retransmits the power usage as digital data to the utility using a cellular telephone transmitter. The utility needs a computer, a modem, and specialized software to receive and analyze the digital data from the cellular telephone transmitter. However, the CPS I system requires two separate enclosures to be mounted in the vicinity of the customer which increases the likelihood that the customer will notice the check meter. In addition, the utility is required to use specialized software operating on the computer to receive and analyze the data obtained from the cellular phone transmitter. Further, cellular telephone communications are highly susceptible to dropouts which then require the data to be retransmitted until valid data is received by the utility. The dropouts and potential corruption of the digital data increases the likelihood that the utility will obtain a false reading of the actual power usage.
Portable check meters normally include both a voltage input (or transformer) that is directly connected to the wire to sense voltage and a current transformer that encircles the wire to sense current flowing within the wire. The voltage and current measurements are multiplied together to obtain the power usage. Unfortunately, utility employees periodically install the current transformer in the reverse direction thereby causing the current induced in the current transformer to have the wrong polarity. The improper current polarity may result in the portable check meter calculating an incorrect power usage. If the current transformer is not properly connected to the wire then the utility employee must return to and reconnect the current transformer to the wire with the proper orientation. The utility employee returning to the check meter increases the likelihood that the customer will detect the monitoring of their power usage and also subjects the utility employee to further danger.
What is desired, therefore, is a portable check meter that reduces the likelihood of transmitting false data to the utility. Also, the check meter should eliminate the need for a computer and specialized software to receive and display the power usage while minimizing the amount of equipment installed at the customer. Further, the check meter should minimize the time necessary for installation and ensure that the utility employee orientates the current transformer in the proper direction. In addition, the check meter should reduce the need for utility employees to be in the vicinity of the customer after installation.
SUMMARY OF THE PRESENT INVENTION
The present invention overcomes the aforementioned drawbacks of the prior art by providing an improved power measurement system for calculating the power flow within a wire to a customer and transmitting an indication of the power flow to a remotely located operator. The measurement system includes both a current transformer that senses current within the wire and generates a first output signal and a voltage input that senses voltage within the wire and generates a second output signal. A measurement device receives both the first and second output signals and in response generates a third signal representative of the power flow within the wire. The measurement device includes both a speech encoding circuit that receives the third signal and in response generates a voice signal, and a transmitter that receives the voice signal and transmits the voice signal to the remotely located operator.
The use of the voice signal in the present invention operates on the basis of relying on the recognition of the human brain to understand voice or speech, even if slightly or severely distorted by limitations in cellular telephone transmission technology. If a few bits are dropped in the voice pattern or a dropout occurs, the speech pattern is still recognizable by the utility employee.
In the preferred embodiment the measurement also includes internal circuitry that detects the polarity of the current transformers. This involves detection of the duration which the voltage and current signals have the same and different polarities. If the voltage and current signals over a cycle have different polarities more than they have the same polarity then the internal circuitry reverses the polarity of the current transformer. This assures that the polarity of the current transformer is proper, regardless of the orientation in which it was installed.
The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of the invention, taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a power distribution system to a customer, including a power measurement system.
FIG. 2 is a block diagram of an exemplary embodiment of the power measurement system of the present invention, including a phase and gain circuit.
FIG. 3 is a block diagram detailing the phase and gain circuit of FIG. 2.
FIG. 4 is a graphical representation of current and voltage signals within a wire indicating the duration that the voltage and current signals have the same and different polarities.
FIG. 5 is a graphical representation of the sampling of a current or voltage waveform over one cycle.
FIG. 6 is a graphical representation of partial sampling of the current or voltage waveform of FIG. 5.
FIG. 7 is a graphical representation of further partial sampling of the current or voltage waveform of FIG. 5 shifted slightly forward in time from the sampling of FIG. 6.
FIGS. 8 to 20 are circuit diagrams of the preferred embodiment of the power measurement system of FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a utility customer 10 has an incoming power line 12 which normally includes two hot wires and a common wire. The power line 12 is typically connected to a main line 14 at a utility pole which belongs to a power utility 15. A standard power meter 16 is located adjacent to the customer 10 in order to determine the customer's power usage for periodic billing purposes. If the utility 15 suspects that the customer is stealing power then the utility 15 installs a check meter 18 on the utility pole to monitor the customer's power usage. Unfortunately, the installation of the check meter 18 may alert the customer 10 that the utility is monitoring their power usage, and subject utility employees to danger during installation and subsequent adjustment of the check meter 18.
Referring to FIG. 2, the check meter 18 of the present invention includes a microprocessor 20. The microprocessor 20 is preferably a Motorola MC68HC711E9 which includes internal analog-to-digital and digital-to-analog converters. A system clock 22 provides a clock signal to the microprocessor 20. A temperature sensor 24 allows the check meter 18 to provide the utility 15 with temperature measurements and also internal temperature compensation for the electronics within the check meter 18.
A pair of split core current transformers 26a and 26b sense the current level within the respective hot wire 27a and 27b of the power line 12, and in response each current transformer 26a and 26b generates an output voltage proportional to the current level within the respective wire 27a and 27b. The current transformers 26a and 26b may be any type of device that senses the current flowing in a wire. A respective phase and gain circuit 28a and 28b receives the output voltage from the respective current transformer 26a and 26b. The microprocessor 20 through lines 30a and 30b adjusts the voltage gain of respective phase and gain circuits 28a and 28b. The gain values are set during calibration of the check meter 18. In addition, the phase and gain circuits 28a and 28b rectify the received voltage signals. The microprocessor 20 and the phase and gain circuits 28a and 28b determine if the phase of each of the sensed current signals is correct, as described later. Rectified analog voltage outputs 31a and 31b from the respective phase and gain circuits 28a and 28b are representative of the current level within the respective wire 27a and 27b.
A pair of voltage inputs (or voltage transformers) 32a and 32b are connected to the respective wire 27a and 27b. The voltage inputs 27a and 27b are preferably clips connected directly to the respective wire 27a and 27b. A pair of signal conditioning circuits 34a and 34b amplify, rectify, and filter the voltage output from the respective voltage inputs 32a and 32b. The voltage output 29a and 29b of each of the signal conditioning circuits 34a and 34b is a rectified analog voltage representative of the voltage level within the respective wire 27a and 27b. The rectified analog voltage outputs from both the signal conditioning circuits 34a and 34b and the phase and gain circuits 28a and 28b are sampled and converted by analog-to-digital converters within the microprocessor 20 to a set of digital values for further processing. A nonvolatile RAM 40 stores sampled data and other suitable data for the check meter 18.
Zero volt crossover detector circuits 36a, 36b, 36c, and 36d detect the zero crossover of each of the respective input voltage signals that may be used to determine the start of each period of the current and voltage waveforms within the wires 27a and 27b by the microprocessor 20. The current and voltage waveforms within the wires 27a and 27b are generally periodic.
To determine the customer's power usage, each of the respective sampled voltage signals from the voltage inputs 32a and 32b and current transformers 26a and 26b are multiplied together to obtain a set of instantaneous power measurements (Power=Current*Voltage). The instantaneous power measurements obtained during a period of time, such as one cycle, are summed together to obtain the power usage per unit time. The period of the cycle may be determined based on the outputs from the crossover detectors 36a-36d or a timing sequencer 56, described later. Unfortunately, the polarity of the output voltage from one or more of the current transformers 32a and 32b may have the incorrect polarity if improperly connected to the respective wire 27a and 27b by the utility employee. If one or both of the current transformers 32a and 32b is improperly connected, the utility employee previously had to return to the check meter 18 to reverse the orientation of the current transformer which adds expense to the surveillance, may jeopardize the secrecy of the surveillance, and may place the utility employee in further danger.
The combination of the crossover detectors 36a-36d, the phase and gain circuits 28a and 28b, and the microprocessor 20, collectively determine if the polarity of the output voltages from the current transformers 32a and 32b are correct.
Referring to FIG. 3, each of the crossover detectors 36a-36d is principally a voltage comparator 52 that produces a positive voltage output (logical 1) when its inverting input voltage is negative and produces a negative voltage output (logical 0) when its inverting input voltage is positive. Each of the phase and gain circuits 28a and 28b includes a phase circuit 50 and the timing sequencer 56. One phase and gain circuits will be described for one wire with the other being the same. The positive and negative rectangular waveforms from the crossover circuits 36c and 36d are the input voltage waveforms 54a and 54b to the phase detector 50. The phase detector 50 is preferably an XOR gate (exclusive OR), and produces the following outputs:
______________________________________Voltage CurrentInput Transformer PhaseComparator 36c Comparator 26d DetectorOutput Output 50 Output______________________________________High Volts ("1") High Volts ("1") Low Volts ("0")High Volts ("1") Low Volts ("0") High Volts ("1")Low Volts ("0") High Volts ("0") High Volts ("1")Low Volts ("0") Low Volts ("0") Low Volts ("0")______________________________________
The output waveform from the phase detector 50 has a zero basis value (low volts) when both the voltage inputs have the same polarity. This indicates that the current and voltage in the respective wire have the same polarity. An output waveform with a (high) logic 1 voltage, indicated by a logic 1 or positive voltage pulse, indicates the time during which both the voltage and current signals do not have the same polarity. The duration which the current and voltage signals have the same and different polarities is illustrated in FIG. 4.
The total power is the summation of each of the instantaneous power calculations where the voltage and current signals have the same polarity as indicated by the phase detector output 50 having a low voltage, from which the instantaneous power calculations are subtracted where the polarity of the voltage and current signals are different as indicated by the phase detector output 50 having a high output. This provides the correct total power value over a period of time.
To determine if the current transformers are providing signals with the proper polarity, the microprocessor 20 determines if during a cycle there are more low voltage outputs from the phase detector 50 indicating the current and voltage have the same polarity than the total high voltage outputs from the phase detector 50 indicating that the current and voltage have different polarities. If this is the case, then the microprocessor 20 knows that the current transformer is properly oriented. Otherwise, the microprocessor 20 automatically corrects the polarity of the current transformer by logically inverting (reversing) the phase indication values from the phase detector 50. This alleviates the previous need for utility employees to return to the check meter 18 and reorient the current transformer. The aforementioned power calculation technique is especially useful when the microprocessor 20 samples rectified signals, as in the present check meter 18, because rectified signals do not contain polarity information. The phase detector 50 is preferably an XOR gate.
The timing sequencer 56 receives the output from the voltage crossover detector 36c and generates an output trigger signal 57 that indicates the start of each cycle of the generally periodic voltage waveform within the wire. The timing sequencer 56 identifies each cycle of the input signal so that each cycle can be identified and sampled individually.
Referring to FIG. 5, the power is more specifically calculated by reconstructing a power wave (Power=Current*Voltage) from a large number of voltage, current, and phase determinations. Each sample taken requires a few bytes to store its voltage, current, and phase values. A high clock rate would be needed to sample the waveform at high rates. In order to reduce the need for high clock speeds and excessive memory to store the samples, the check meter 18 samples multiple cycles and overlays them to obtain a more accurate resultant power usage. Multiple power data samples are obtained in groups, each group measuring at points that are shifted slightly later in time, so as to fill in the gaps between the sample of the previous sample groups. The first data acquisition group, as shown in FIG. 6, obtains the data samples starting at the positive edge of the voltage crossover point, and then proceeds to acquire the next sample just a few hundred microseconds later, until the final sample is near, but, not over the negative going edge of the voltage crossover point. At the negative going edge voltage crossover point, the data sampling begins again, obtaining samples at exactly the same spacing as in the positive half cycle. When the first data acquisition group has finished, the data samples are evaluated and combined into a single partial power usage. The second data acquisition group, as shown in FIG. 7, in like manner obtains its data samples, however, the starting sample is delayed slightly in time from the voltage crossover points. This is to cause the sampling of data to be slightly shifted to later points all across the waveform. When the second data acquisition group has finished, the collected data samples are evaluated and added to the first partial power usage. Preferably 256 samples are obtained across the power wave which may require several cycles. The result has a high degree of accuracy, especially for distorted waveforms and current phase shifting.
The present inventors determined that using a cellular phone transmitter to transmit digital data to the utility 15 is prone to errors due to the inherent limitations of cellular phone transmissions. Also, specialized software, a computer, and a modem are not always available to receive and display the data. The present inventors came to the realization that they could eliminate the digital data transmission limitation, not by including redundant check bits or transmitting the digital data multiple times to the receiving computer, but instead relying on the recognition of the human brain to understand voice or speech even if severely distorted. If a few bits are dropped in the voice pattern or a dropout occurs, the speech pattern is still recognizable by the utility employee. Referring again to FIG. 2, the check meter 18 includes a cellular phone interface 74 which includes cellular phone receiver and transmitter circuitry. The utility employee calls the cellular phone number of the desired check meter 18 and issues in commands by selected combinations of touchtone (DTMF) numbers. The check meter 18 includes a DTMF transceiver (dual-tone multi-frequency) 72 that receives and interprets touchtone inputs from a touchtone phone. In response, the check meter 18 provides the requested data and encodes it using a voice synthesizer 70 in a human voice. The generated voice signals are transmitted to the utility employee using the cell phone interface 74. Alternatively, the measurement system may use any type of telecommunication transmission and reception system that permits the use of voice transmissions. The utility employee may query the check meter 18 from anywhere that he has access to a phone. Voice synthesis reduces the effects of the dropouts inherent in cellular phone technology because the human brain can interpret voice patterns even if some of the data is missing.
The telephone DTMF commands that may be issued to the check meter 18 include, for example requests for:
(a) date;
(b) repeat last information requested;
(c) current amperage detected;
(d) current voltage detected;
(e) kilowatt-hour reading;
(f) resetable kilowatt-hours;
(g) peak amps;
(h) temperature;
(i) clear resetable kilowatt-hours;
(j) clear peak amps;
(k) begin investigation; and
(l) complete investigation.
The current amperage command for each current transformer 26a and 26b instantly permits the utility 15 to determine if the amperage is unusually high, which could be indicative of when the customer 10 is likely stealing power. The current voltage command for each voltage input 32a and 32b permits the utility 15 to verify that a suitable voltage is being provided to the customer. The peak amps command preferably also includes the date and time so that the utility can tell when the customer 10 is likely stealing power, as described later. Clear peak amps command permits the peak amp reading to be set to zero. The resetable kilowatt-hours command is the same as the kilowatt-hours command, except that the resetable kilowatt-hours can be cleared to zero unlike the kilowatt-hours. During an investigation, described below, the resetable kilowatt hours is used to directly read the kilowatt hours of power consumed during an investigation without having to subtract the previous kilowatt-hour reading from the current kilowatt-hour reading to determine the total power usage.
One method of using the check meter 18 is to first determine if the customer is likely stealing power by noting any difference between the check meter 18 and the power meter 12 readings. Thereafter the utility employee can use the peak amperage command to determine when it is likely that the customer 10 is stealing power. As an example, some customers attempt to steal power when they believe it is less likely that they will be detected, such as during the early morning. During the daytime the customer may simply use a normal amount of power. Accordingly, the utility employee will attempt to determine those times that the amperage or peak amperage is unusually high and attempt to obtain a court order to enter the premises while the customer is likely actually stealing power.
An investigation is an automatic method of obtaining useful information during a period of time. The beginning of an investigation involves the microprocessor 20 (1) saving the time and date, (2) saving the non-resetable kilowatt-hour reading, (3) saving the amps reading, (4) clearing the peak amps reading, and (5) clearing the resetable kilowatt-hour reading. At the end of the investigation period the microprocessor 20 does the following: (1) saves the present time and date, (2) saves the non-resetable kilowatt-hour reading, (3) saves the resetable kilowatt-hour reading, (4) saves the amps reading, and (5) saves the peak amps reading. Upon request, the accumulated data is transmitted to the utility employee.
The actual circuit layout of the check meter 18 is shown in FIGS. 8-20. The check meter could be designed, with minor modifications, for use in a three phase system.
The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.
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A power measurement system calculates the power flow within a wire to a customer and transmits an indication of the power flow to a remotely located operator. The measurement system includes both a current transformer that senses current within the wire and generates a first output signal and a voltage input that senses voltage within the wire and generates a second output signal. A measurement device receives both the first and second output signals and in response generates a third signal representative of the power flow within the wire. The measurement device includes both a speech encoding circuit that receives the third signal and in response generates a voice signal, and a transmitter that receives the voice signal and transmits the voice signal to the remotely located operator.
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This application is a continuation of application Ser. No. 912,162 filed Sept. 24, 1986, abandoned, which is a continuation of Ser. No. 748,652 filed June 25, 1885, abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a sintered article of silicon carbide exhibiting resistance to oxidation, resistance to thermal shock, resistance to corrosion, and strength at elevated temperatures and, at the same time, possessing high density.
2. Description of the Prior Art
In recent years, sintered articles of silicon carbide, owing to their feature of excelling in resistance to oxidation, resistance to thermal shock, resistance to corrosion, and strength at elevated temperatures, have come to find growing utility in applications to various structural materials, check valves and sealing members designed to handle corrosive liquids, heat-exchanger members for high-temperature furnaces, members expected to withstand heavy friction. Even the desirability of sintered articles which are substantially devoid of pore and are stronger has come to find recognition.
As methods of producing such silicon carbide, (A) chemical vapor deposition (CVD), (B) reaction sintering, and (C) conventional sintering have been known. The method of (A) is capable of producing homogeneous and compact silicon carbide generally only in the form of film and, therefore, is practically, barely suitable for the purpose of coating various materials. The method of (B) which comprises sintering a compact of silicon carbide powder or a mixed powder of silicon dioxide and silicon carbide is capable of producing articles of large dimensions but low density. Therefore, this method is now applied only to production of refractories and heat generators. For the production of sintered articles of large dimensions and high density, the method of (C) is considered as the optimum means.
Incidentally, silicon carbide, which is a compound of high covalent bond property and, therefore, is hard, tough, and stable at elevated temperatures, exhibits very poor sintering property and does not permit easy production of sintered articles when conventional sintering process is applied. Many studies have been being reported concerning adding various sintering aids to improve its sintering property of silicon carbide powder. For example, R. Alliegro et al. Journal of the American Ceramic Society, Vol. 39, pp. 386-389 (1956), the specifications of Japanese Patent Laid-open Publication Nos. 49-007311, 49-099308, 50-078609, 51-065000, 53-067711, and 53-084013 disclose the effect of use of Al, Fe, B, B 4 C, etc. as sintering aids permits production of sintered articles showing low pore contents and high strength.
The strength of sintered articles is effected greatly by the factors of (A) porosity, (B) surface flaw, and (C) grain size. The problem of porosity of (A) can be remarkably solved by using various sintering aids as mentioned above. Although, the sintered articles so produced by the incorporation of such sintering aids, contain extents of microscopic pores. Causing of said (B) surface flaw can be avoided by payment of careful attention to fabrication. The problem caused by the factor from grain size of (C) is most difficult, because of grain growth during the course of sintering, and difficulty of retaining the starting fine grains during the course of sintering. This inevitable growth of grains constitutes itself the cause for the failure of sintered articles to acquire strength beyond a certain limit. This fact is reported by S. Prochazka et al., Am. Caramic Soc. Bull. 52, 885-891 (1973) purporting to conclude that owing to growth of crystal grains, the produced sintered articles fail to acquire any appreciable improvement in strength when using B as a sintering aid.
With a view to eliminating the drawback mentioned above, the inventors have already disclosed that a sintered article of silicon carbide containing erbium oxide and aluminum oxide as an independent composition shows features of high density and extremely fine size of crystal grains in the filed Japanese Patent Application No. 58-190361. Even the sintered article still contains pores measuring approximately 2 μm and is recognized as coarse as 8.5 μm. Thus, the need of producing sintered articles of silicon carbide possessing still higher density and containing crystal grains of still finer size still remains yet to be satisfied.
SUMMARY OF THE INVENTION
An object of this invention is to provide a high-density sintered article of silicon carbide containing finer pores and possessing more compact texture than the conventional sintered article of silicon carbide. Specifically, this invention aims to provide a high-density sintered article of silicon carbide containing pores measuring not more than 1.0 μm and crystal grains measuring not more than 5 μm.
The other and further objects and characteristics of this invention will become apparent from the further disclosure of this invention to be made in the following detailed description of a preferred embodiment, with reference to the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
The drawing attached hereto is an explanatory diagram illustrating a high-temperature fatigue test conducted in Example 6.
DETAILED DESCRIPTION OF THE INVENTION
The sintered article of silicon carbide of the present invention has erbium oxide and aluminum oxide contained therein in the form of a composite oxide.
To cite a typical example of the composite oxide, they may be contained in the form of a garnet of the following formulas.
Er.sub.3 (Al, Er).sub.2 (AlO.sub.4).sub.3 (1)
(Er, Al).sub.3 Al.sub.2 (AlO.sub.4).sub.3 (2)
As the garnet powder represented by the aforementioned formula (1)-(2), a polycrystalline powder obtained by mixing aluminum oxide powder with erbium oxide powder and subjecting the produced mixed powder to a solid-phase reaction at elevated temperatures (generally about 1300° to 1600° C.) can be used, for example.
Such solid-phase reaction described above does not always give rise to a product of the composition Er 3 Al 2 (AlO 4 ) 3 . Often, the two powdered oxides undergo mutual substitutive solid solution and give rise to garnets of the compositions indicated in (1) and (2) above. Otherwise, a garnet of the composition Er 3 Al 2 (AlO 4 ) 3 can be used. Besides such garnets, a composition represented by the formula Er x Al.sub.(1-x) O 3 (wherein x<1) can be used.
The amount of erbium oxide in the composite oxide must be at least 21% by weight. If this amount falls short of the lower limit just mentioned, the density of the sintered article based on the theoretical value is insufficient and bending rupture and other properties become inferior. If this amount is as large as 15% by weight, growth of crystal grains is observed to occur and, as the result, the magnitudes of bending rupture and impact value are lowered and most of the other properties are liable to be impaired. Thus, this amount is not allowed to exceed 12% by weight.
As concerns the amount of aluminum oxide, if the amount reaches 3% by weight, the properties such as breaking strength are observed to decline. If this amount is nil, the effect of the addition of a garnet formed jointly of erbium oxide and aluminum oxide is completely absent. Thus, the amount is desired not to exceed 2% by weight.
Although the mechanism of compaction of the structure by this composite oxide remains yet to be elucidated, it is considered that the low energy of activation is made the composite oxide to undergo solid solution in silicon carbide and consequently promote the sintering of silicon carbide.
This invention further embraces the addition of 0.5 to 6.0% by weight of at least one element selected from the group of components indicated below or its varying compound such as oxide, nitride, boride, or carbide, as an agent for promoting the compaction of sintered article. Concrete examples of the element possessing the aforementioned function include titanium, vanadium, chromium, manganese, magnesium, yttrium, zirconium, niobium, molybdenum, barium, lanthanum, cerium, gadolinium, hafnium, tantalum, tungsten, thorium, and cesium.
The second additive element so used for promoting the sintering proves virtually effectless if the amount of this element added is 0.3% by weight, and is required to be at least 0.5% by weight. If this amount is as large as 6% by weight, the crystal grains are observed to grow in size and the properties of the sintered article are degraded. The effect of the added element upon the compaction of the sintered article has not yet been fully elucidated. It has been experimentally ascertained to the inventors that this added element synergistically cooperates with the aforementioned composite oxide to decrease microscopic pores to a great extent.
Optionally, part of silicon carbide may be substituted with Be, BeO, B, or B 4 C. When this substitution is effected, the addition of a proper amount of the composite oxide of erbium oxide and aluminum oxide enables the produced sintered article to acquire a compact structure formed of extremely fine grains. If the amount of substitution is not more than 0.5% by weight, the effect of the added element is substantially nil. If the amount is as large as 3.0% by weight, however, the bending rupture and the hardness of the sintered silicon carbide are observed to decrease. Thus, the amount of substitution must not exceed 2% by weight and is desired to fall in the range of 0.5 to 2% by weight.
It has also been ascertained experimentally that the results of the present invention are not affected at all even when silicon carbide contains 0.5 to 2% by weight of free carbon.
In the manufacture of the sintered article according to this invention, the composite oxide, the agent for promoting the sintering, etc. are required to be uniformly dispersed in silicon carbide.
For the manufacture of the sintered article according to this invention, the conventional sintering method such as hot press method or HIP method can be advantageously utilized. In order to obtain compact and strong sintered articles, the hot pressure temperature is required to exceed 1900° C. If this temperature is as high as 2100° C., however, growth of grains occurs heavily and excessive growth of grains sets in before the compaction of structure proceeds sufficiently and, as the result, pores persist in the produced sintered article. For the purpose of the hot press method, the pressure has only to exceed 100 kg/cm 2 to be sufficient. No upper limit is specifically fixed for this pressure. The sintering can be carried out effectively in a vacuum or in an atmosphere of inactive gas. In the case of the HIP method, the sintering is desired to be carried out in an atmosphere of inactive gas. Even by the normal sintering method, the sintered article can be produced in substantially the same quality. When the sintering is performed in the atmosphere of inactive gas without application of pressure, the temperature falls in the range of 2050° to 2300° C. In the atmosphere of compressed gas under 10 atm, the temperature falls in the range of 2000° to 2250° C.
EXAMPLES
Example 1
First, aluminum oxide powder of purity of 99.9% and average particle diameter of 0.4 μm and erbium oxide powder of purity of 99.9% and average particle diameter of 0.8 μm were mixed in a varying ratio indicated in Table 1. The mixed powder was heated at 1300° to 1600° C. for three to ten hours to synthesize a garnet. The garnet was finely ground to an average grain size of 0.5 μm. The garnet powder was mixed with silicon carbide powder of purity of 98.5% and average grain size of 0.5 μm and magnesium oxide powder of purity of 99.9% and average grain size of 1 μm in a varying ratio indicated in Table 1. The resultant composition was wet-pulverized in a ball mill mixer for 15 hours and then dried thoroughly to prepare a raw material for sintering. A graphite mold the square of 50 mm in area and 60 mm in height was packed with the raw material and inserted in a high-frequency coil. The raw material was held at 1950° C. under 200 kg/cm 2 of pressure for 60 minutes and then relieved of pressure and left cooling off. As the result, a sintered article 50×50×5.5 mm in size was obtained. The sintered article so obtained was cut and ground with a diamond cutting tool to be 10 test pieces 3×4×36 mm. These test pieces were tested for various properties. The results are shown in Table 1.
The test pieces were visually examined to test for structure. Coarse pores measuring about 2 μm are indicated by the mark X and fine pores measuring not more than 1 μm by the mark G.
TABLE 1-1__________________________________________________________________________(Example) Run No. 1 2 3 4 5 6 7 8 9__________________________________________________________________________ Mixing ratio SiC 97 95 94 93 90 86 84 83 81(% by weight) MgO 3 3 3 3 3 3 3 3 3 Garnet Al 2O.sub.3 -- 1 1 2 2 1 1 2 1 Er.sub.2 O.sub.3 -- 1 2 2 5 10 12 12 15 Al.sub.2 O.sub.3 -- -- -- -- -- -- -- -- -- Er.sub.2 O .sub.3 -- -- -- -- -- -- -- -- --Relative density (%) 74.9 87.2 98.8 98.9 99.1 99.1 99.3 99.1 95.3Grain size (μm) 1.0 3.5 3.5 4.0 4.0 4.5 4.0 4.5 8.5Bending rupturestrength (kg/mm.sup.2) 20 41 84 88 88 88 85 83 63Charpy impactvalue (kg · m/cm.sup.2) 0.06 0.11 0.24 0.25 0.25 0.25 0.25 0.25 0.22Hardness (H.sub.R 30N) -- 86.0 93.9 94.0 95.5 95.1 95.3 95.0 93.8Pore size (G, X ) X X G G G G G G X__________________________________________________________________________
TABLE 1-2______________________________________(Comparative experiment) Run No. 10 11 12______________________________________Mixing ratio SiC 94 90 86(% by weight) MgO 3 3 3 Garnet Al.sub.2 O.sub.2 -- -- -- Er.sub.2 O.sub.3 -- -- -- Al.sub.2 O.sub.3 1 2 1 Er.sub.2 O.sub.3 2 5 10Relative density (%) 97.7 97.9 98.8Grain size (μm) 3.5 7.0 7.5Bending rupturestrength (kg/mm.sup.2) 81 82 79Charpy impact value (kg · m/cm.sup.2) 0.20 0.23 0.23Hardness (H.sub.R 30N) 93.5 93.8 93.7Pore size (G, X ) X X X______________________________________
Example 2
Same test pieces in Example 1 were cut with a diamond cutting tool to be a plate 10×10×5 mm in size. Those plates were given to surface polishing with #200 grit diamond. And the polished surface, 10×10 mm, of the plate was blasted with abrasive grits (METCOLITE C, No. 40) blown at a distance of 50 mm under air pressure of 5 kg/cm 2 by a sand blasting machine provided with a nozzle 8 mm in inside diameter, to test for weight loss. The results are shown in Table 2.
TABLE 2______________________________________Run No. 1 2 4 5 8 9______________________________________Loss of weight, 2.03 0.98 0.65 0.60 0.60 1.11g/(cm.sup.3 · hr)______________________________________
Example 3
Same test pieces in Example 1 were out with a diamond cutting tool to obtain a plate 10×10×5 mm in size. All the surfaces of this plate were wrapped with #200 grit diamond. The test piece thus prepared was left standing at 1300° C. for 20 hours in air, to test for weight increase per unit area. The results are shown in Table 3.
TABLE 3______________________________________Run No. 1 2 4 5 8 9______________________________________Weight increase 15.0 5.2 0.4 0.3 0.3 6.7× 10.sup.-7 g/mm.sup.2______________________________________
Example 4
Same test pieces in Example 1 were cut with a diamond paste to obtain a rod 3×4×36 mm in size. All the surfaces of this rod were wrapped with a diamond paste. The test pieces so prepared were subjected to Charpy impact test at 950° C. in the atmosphere. The results are shown in Table 4.
TABLE 4______________________________________Run No. 1 2 4 5 8 9______________________________________Impact strength 0.08 0.22 0.42 0.42 0.43 0.21at elevatedtemperatures,kg · cm.sup.2______________________________________
Example 5
Same test pieces in Example 1 were directly subjected to high-temperature fatigue test. Specifically, with a flex tester, the samples are held in the position by the single point loading method with the span distance of 20 mm under the atmospheric pressure at 1000° C. in air stress cycles 1325 CTM. The repeated stress were applied in a pattern as illustrated in the accompanying drawing, under the conditions such as to satisfy σ max =15 kg/cm 2 and i=0.73 wherein σ max denotes the upper limit of repeating stress, σ min denotes the lower limit of repeating stress, σ m denotes the average stress, σ a denotes the amplitude of stress, and i denotes the ratio of σ a /σ m . The results are shown in Table 5.
TABLE 5______________________________________Run No. 1 2 4 5 8 9______________________________________Flexible fatigue number 9.8 0.8 8.2 4.7 5.6 0.6of cycle × × × × × × 10.sup.2 10.sup.4 10.sup.4 10.sup.5 10.sup.5 10.sup.4______________________________________
Example 6
First, 10% by weight of aluminum oxide powder of purity of 99.9% and average grain size of 0.4 μm and 90% by weight of erbium oxide powder of purity of 99.9% and average grain size of 0.8 μm were mixed. The mixed powder was heated at 1400° C. for five hours to synthesize a garnet. The garnet so obtained was finely ground to average grain size of 0.5 μm. The resultant fine powder used in an amount of 10% by weight, a varying second additive element for promotion of sintering used in a varying amount indicated in Table 6, and the balance to make up 100% by weight of silicon carbide of purity of 98.5% and average grain size of 0.5 μm were wet pulverized in a ball mill mixer for 15 hours. From the resultant composition, a sintered articles were produced by same procedure in Example 1. The sintered article was tested for various properties. The results are shown in Table 6.
TABLE 6__________________________________________________________________________Second additiveelement forpromoting Bending Charpysintering Relative Grain rupture impactcompound/amount density size strength value Hardness(% by weight) (%) (μm) (kg/mm.sup.2) (kg.m/cm.sup.2) (H.sub.R 30N)__________________________________________________________________________TiO.sub.2 /0.3 98.0 4.0 81 0.23 94.7Cr.sub.2 O.sub.3 /0.5 98.5 4.0 83 0.24 95.1MnO.sub.2 /3 98.9 4.5 83 0.25 95.0MgO/0.3 98.1 4.5 81 0.23 94.6MgO/0.5 98.5 4.5 84 0.24 95.0MgO/3.0 99.0 4.5 88 0.25 95.0MgO/6.0 99.1 5.0 84 0.25 94.6MgO/7.0 98.8 6.0 71 0.23 92.2Y.sub.2 O.sub.3 /0.3 98.0 4.5 79 0.22 94.5Y.sub.2 O.sub.3 /0.5 98.6 4.5 83 0.25 95.3Y.sub.2 O.sub.3 /3.0 98.9 4.5 87 0.24 94.9Y.sub.2 O.sub.3 /6.0 99.0 5.0 84 0.25 95.0Y.sub.2 O.sub.3 /7.0 98.8 6.5 72 0.22 92.3ZrSiO.sub.4 /3 99.2 4.5 85 0.25 95.0Nb.sub.2 O.sub.3 /3 99.4 4.5 83 0.24 95.2Mo/1.BaO/1 99.0 4.5 86 0.25 94.9La.sub.2 O.sub.3 /0.5CeO.sub.2 /2 99.4 4.5 83 0.24 95.2W/0.5Sm.sub.2 O.sub.3 /0.5 99.2 5.0 87 0.26 94.8__________________________________________________________________________
Example 7
A part of silicon carbide powder used for sintering was substituted with Be, BeO, B, or B 4 C.
First, aluminum oxide powder of purity of 99.9% and average grain size of 0.4 μm and erbium oxide powder of purity of 99.9% and average grain size of 0.8 μm were mixed in a varying ratio indicated in Table 7. The powder mixtures were heated at 1300° to 1600° C. for three to ten hours to synthesize a garnet. Then, the garnet so obtained was finely ground to average grain size of 0.5 μm. The finely ground garnet powder was mixed with silicon carbide powder of purity of 98.5% and average grain size of 0.5 μm and magnesium oxide powder of purity of 99.9% and average grain size of 1 μm in a varying ratio indicated in Table 7. The composition was wet pulverized in a ball mill mixer for 15 hours. Then by following the procedure of Example 1, the raw material so prepared was subjected to hot press sintering at 1950° C. The sintered article consequently produced was tested for various properties. The results are shown in Table 7.
TABLE 7__________________________________________________________________________ Bending CharpyMixing ratio Relative Grain rupture impactGarnet (% by weight) density size strength value HardnessAl.sub.2 O.sub.3 Er.sub.2 O.sub.3 MgO Additive SiC (%) (μm) (kg/mm.sup.2) (kg · m/cm.sup.2) (H.sub.R 30)N__________________________________________________________________________2 3 3 -- bal. 97.5 6.0 79 0.22 93.62 3 3 0.5 B bal. 98.5 4.0 84 0.24 95.62 3 3 3.0 B bal. 98.3 5.0 75 0.21 94.82 5 3 0.5 B.sub.4 C bal. 98.3 5.0 86 0.24 95.32 5 3 3.0 B.sub.4 C bal. 98.6 5.5 78 0.23 94.52 5 3 1.5 Be bal. 98.6 4.0 85 0.25 95.32 5 3 3.0 Be bal. 97.3 5.5 57 0.22 95.02 10 3 0.5 BeO bal. 98.6 4.5 85 0.25 95.42 10 3 3.0 BeO bal. 97.0 6.0 73 0.22 95.42 10 3 1.0 BeO bal. 98.0 5.0 85 0.24 96.0 1.0 B__________________________________________________________________________
Sintered articles of silicon carbide, according to this invention, as described in above examples, shows increased density by the addition of the composite oxide of aluminum oxide and erbium oxide and an element capable of promoting the sintering, and toughness by making the crystal grain size below 5 μm to be very fine, and decreasing the size of pores below 1 μm.
In contrast, in the cases of using mixed powder consisting of aluminum oxide and erbium oxide as shown in above comparative experiments in Table 1-2, the pores contained in the sintered article are increased being as 2 μm.
MERITORIOUS EFFECTS OF INVENTION
Thus, the sintered article of this invention, is preferably applicable to structural materials and abrasive materials which are expected to offer high resistance to oxidation, thermal shock, and corrosion and retain high strength at elevated temperatures.
Since the sintered article contemplated by the present invention can be manufactured by the hot press method or the HIP method, it can be obtained easily in a large size. Even when the sintered article of this invention is manufactured by the normal sintering method, it acquires substantially the same quality as when it is manufactured by the hot press sintering method.
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A sintered article of silicon carbide containing 2 to 12% by weight of erbium oxide, not more than 2% by weight of aluminum oxide, existing in the form of a composite oxide exhibits remarkable characteristics in resisting to oxidation, thermal shock and corrosion, and shows increased strength at elevated temperatures due to their effect to compaction of resulting structure of the sintered article due to retaining fineness of crystal grains. Those meritorious effects can be enhanced by adding to the aforementioned composition 0.5 to 6.0% by weight of at least one element selected from among titanium, vanadium, chromium, manganese, magnesium, yttrium, zirconium, niobium, molybdenum, barium, lanthanum, cerium, gadolinium, hafnium, tantalum, tungsten, thorium, and cesium or a compound of this element.
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RELATED APPLICATIONS
This application claims the benefit of the filing date of U.S. Provisional Application No. 60/245,188, filed Nov. 3, 2000, and Canadian Patent Application No. 2,345,560, filed Apr. 27, 2001, under the provisions of 35 U.S.C. § 119.
FIELD OF THE INVENTION
The invention relates to rotary drilling, and more particularly, to steered directional drilling with a rotary drilling tool.
BACKGROUND OF THE INVENTION
In the earth drilling art, it is well known to use downhole motors to rotate drill bits on the end of a non-rotating drill string. With the increasingly common use of directional drilling, where the well is drilled in an arc to produce a deliberately deviated well, bent subs have been developed for guiding the downhole motors in a desired drilling direction. The bent subs are angled, and thus cannot be used in association with rotating drill strings.
This invention is directed towards a tool that permits steered directional drilling with a rotary drilling tool.
SUMMARY OF THE INVENTION
The device contemplated provides a method for positioning the drill bit in a drilling operation to achieve small changes in hole angle or azimuth as drilling proceeds. Two different positions are available to the operator. The first is a straight ahead position where the tool essentially becomes a packed hole stabilizer assembly. The second position tilts the bit across a rotating fulcrum to give a calculated offset at the bit-formation interface. The direction that the bit offset is applied in relation to current hole direction is controlled by positioning the orienting pistons prior to each drilling cycle, through the use of current measurement-while-drilling (MWD) technology.
In one aspect of the invention, components of the tool comprise a MWD housing, upper steering and drive mandrel, non-rotating position housing, lower drive mandrel splined with the upper mandrel, rotating fulcrum stabilizer and drill bit.
If, after surveying and orienting during a connection, it is desired to drill with the tool in the oriented position, the rig pumps are activated. The pressure differential created by the bit jets below the tool will cause pistons to open from the ID of the tool into the tool chamber. As the pistons open, they will contact wings that come out into the path of travel of the upper mandrel as it comes down a spline, and bottoms out on the lower drive mandrel. This occurs as the drill string is being lowered to bottom. The extra length provided by the open wings moves a sliding sleeve centered over, but not attached to the upper mandrel, to a new position that in turn forces the orienting pistons to extend out into the borehole annulus. This extrusion pushes the non-rotating sleeve (outer housing) to the opposite side of the hole. When this force is applied across the rotating stabilizer, the stabilizer becomes a fulcrum point, and forces the drill bit against the side of the hole that is lined up with the orienting pistons. The calculated offset at the bit then tends to force the hole in the oriented direction as drilling proceeds. After the drilling cycle is complete, the tool will be picked up off bottom, and as the upper mandrel moves upward on the spline in the lower mandrel, a spring pushes the sliding sleeve back into its normal position, the orienting pistons retract into the outer housing, and the centering pistons come back out into the borehole annulus, thus returning the tool to its normal stabilized position. This cycle may be repeated until the desired result is achieved.
Once the desired hole angle and azimuth are achieved, the following procedure may be implemented to drill straight ahead. After making a connection and surveying, slowly lower the drill string to bottom and set a small amount of weight on the bit. Then engage the rig pumps. This time, when the activation pistons from the ID attempt to open the wings, they will be behind the sliding sleeve assembly, and the sliding sleeve will remain in its normal or centered position throughout the following drilling cycle.
Skillful alternating of the two above drilling positions will yield a borehole of minimum tortuosity, when compared to conventional steerable methods.
These and other aspects of the invention are described in the detailed description of the invention and claimed in the claims that follow.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a side view of a drill string with rotary steerable tool according to the invention;
FIGS. 2A-2D are lengthwise connected sections (with some overlap) through a rotary steerable tool according to the invention showing the tool in pulled back position ready to extend the wings used to move the pistons into the offset drilling position;
FIG. 3 is a cross section along section line 3 — 3 in FIG. 2C;
FIG. 4 is a cross section along section line 4 — 4 in FIGS. 2C and 8C;
FIG. 5 is a cross section along section line 5 — 5 in FIGS. 2C and 8C;
FIG. 6 is a cross section along section line 6 — 6 in FIGS. 2C and 8C;
FIG. 7 is a cross section along section line 7 — 7 in FIGS. 2B and 8B;
FIGS. 8A-8D are lengthwise connected sections (with some overlap) through a rotary steerable tool according to the invention showing the tool in straight ahead drilling position;
FIG. 9 is a cross section along section line 9 — 9 in FIG. 8C;
FIG. 10 is a lengthwise section through a rotary steerable tool according to the invention showing the tool in offset drilling position;
FIG. 11 is a cross section along section line 11 — 11 in FIG. 10;
FIG. 12 is a cross section along section line 12 — 12 in FIG. 10;
FIG. 13 is a cross section along section line 13 — 13 in FIG. 10;
FIG. 14 is a cross section along section line 14 — 14 in FIG. 10;
FIG. 15 is a perspective view of a rotary steerable tool according to the invention showing wings in the extended position with the housing partly broken away to show the mandrel;
FIG. 16 is a perspective view of a rotary steerable tool according to the invention with the housing broken away to show wings in the retracted position;
FIG. 17 is a close-up view of mating dog clutch faces for use in orienting the rotary steerable tool according to the invention;
FIG. 18 is an end view of a rotary steerable tool according to the invention showing pistons set in the offset drilling position; and
FIG. 19 is an end view of a rotary steerable tool according to the invention showing pistons set in the straight ahead drilling position.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In this patent document, “comprising” is used in its inclusive sense and does not exclude other elements being present in the device. In addition, a reference to an element by the indefinite article “a” does not exclude the possibility that more than one of the elements is present. MWD means measurement-while-drilling. All seals and bearings described herein and shown in the drawings are conventional seals and bearings.
Referring to FIG. 1, which shows the overall assembly of a drill string according to the invention, a rotary steerable drilling tool 10 is shown located on a conventional drill string 12 between a conventional MWD tool 14 and a conventional drill bit 16 . As shown more particularly in FIGS. 2A and 2D, rotary steerable drilling tool 10 includes a mandrel 20 having a conventional box connection 22 at an uphole end for connection into drill string 12 and a conventional box connection 24 at a downhole end for connection to a pin connection 26 of a drilling sub 28 . Sub 28 is configured as a rotating stabilizer 17 provided on the drill string between rotary steerable drilling tool 10 and drill bit 16 , and operates as a fulcrum for rotary steerable drilling tool 10 and drill bit 16 to pivot around. Drill bit 16 will conventionally have jets in the bit for egress of fluid from the drill string. At the surface, a conventional rig will include conventional pumps (not shown) for pumping fluid down drill string 12 to drill bit 16 and out the jets in the drill bit.
The components of rotary steerable drilling tool 10 are best seen in FIGS. 2A-2D, which show the tool in the pulled back off-bottom position, ready to set the tool into either a straight ahead drilling position or an offset drilling position. FIGS. 3-7 are sections corresponding to the section lines on FIGS. 2A-2D. FIGS. 15-19 provide perspective views of the tool broken away to show the internal workings. FIGS. 3-7 are sections corresponding to the section lines on FIGS. 2A-2D. FIGS. 8A-8D show rotary steerable drilling tool 10 in a straight ahead on-bottom drilling position. FIG. 9 is a section corresponding to the section line 9 — 9 on FIG. 8 C. The other sections shown on FIGS. 8A-8D correspond to FIGS. 4-7 as well, since the sections do not change in those positions. FIG. 10 shows rotary steerable drilling tool 10 in position for offset drilling, insofar as it is different from the position shown in FIGS. 8A-8D. FIGS. 11-14 are sections corresponding to the section lines on FIG. 10 .
Referring to FIGS. 2A-2D, 3 - 7 , 8 A- 8 D, and 15 - 19 , and particularly to FIGS. 2A-2D, a bore 30 is provided within mandrel 20 for communication of fluid from surface to drill bit 16 . A housing 32 is mounted on mandrel 20 for rotation in relation to mandrel 20 . During drilling, housing 32 is held against rotation by frictional engagement with the wellbore and the mandrel rotates, typically at about 120 rpm. Housing 32 is provided with an adjustable offset mechanism that can be adjusted from the surface so that rotary steerable drilling tool 10 can be operated in and changed between a straight ahead drilling position and an offset drilling position. In the straight ahead drilling position, asymmetry of housing 32 , namely thickening 33 of housing 32 on one side, in combination with pistons on the other side of housing 32 yields a tool that is centered in the hole. In an offset drilling position, pistons on the thickened side of housing 32 drive tool 10 to one side of the wellbore, and thus provide a stationary fulcrum in which mandrel 20 rotates to force the drill bit in a chosen direction. Three hole grippers 15 are provided on the exterior surface of housing 32 downhole of thickened section 33 . One of hole grippers 15 is on the opposite side of the thickened section, and the other two are at about 90 degrees to thickened section 33 . Hole grippers 15 are oriented such that when rotary steerable tool 10 is offset in the hole by ½ degree by operation of the adjustable offset mechanism described below, hole grippers 15 will lie parallel to the hole wall, so that hole grippers 15 make maximum contact with the hole wall. Hole grippers 15 grip the wall of the hole and prevent housing 32 from rotating, as well as preventing premature wear of housing 32 against the wellbore.
Housing 32 has threaded on its uphole end an end cap 34 holding a piston 36 , and on its downhole end another end cap 40 holding a floating piston seal 42 within chamber 44 . Floating piston 42 accommodates pressure changes caused by movement of the housing on mandrel 20 . Housing 32 rotates on mandrel 20 on seven bearings 46 . Mandrel 20 is formed from an upper mandrel 50 and lower mandrel 52 connected by splines 54 . A sleeve 55 , is held in the bore of lower mandrel 52 , and in the downhole end of upper mandrel 50 , by a pin on sub 28 . Appropriate seals are provided as shown to prevent fluid from the mandrel bore from entering between the upper mandrel 50 and lower mandrel 52 at 57 . Downhole movement of upper mandrel 50 in lower mandrel 52 is limited by respective shoulders 59 and 61 . Housing 32 is supported on lower mandrel 52 by thrust bearings 56 on either side of a shoulder 58 on lower mandrel 52 .
The adjustable offset mechanism may for example be formed using plural pistons 60 , 62 and 64 radially mounted in openings in housing 32 . Pistons 60 and 62 are mounted in openings on thickened side 33 of the sleeve, while pistons 64 are mounted on the opposed side. Thickened side 33 has a larger radius than the opposed side, and pistons 64 are extendable outward to that radius. Pistons 62 are at 120 degrees on either side of piston 60 and extend outward at their maximum extension less than the extension of piston 60 when measured from the center of mandrel 50 . Pistons 60 and 62 extend outward to a radius of a circle that is centered on a point offset from the center of mandrel 50 , as shown in FIG. 18 . As shown in FIGS. 4-6 and 12 - 14 , hole grippers 65 are also embedded on either side of housing 32 at 90 degrees to piston 60 . Hole grippers 65 are about 5 inches long, and are oriented, as with hole grippers 15 , so that one edge lies furthest outward. Thus, hole grippers 65 assist in preventing housing 32 from rotating by engaging the hole wall with their outermost edge. Hole grippers 15 and 65 should be made of a suitably hard material, and may, for example, be power tong dies since these are readily available and may be easily removed for replacement. Pistons 60 , 62 and 64 should also be made of a similar hard material.
Pistons 60 , 62 and 64 are radially adjustable by actuation of mandrel 20 as follows. Dog clutch 66 is pinned by pins 68 to mandrel 20 to form a chamber 70 between housing 32 and upper mandrel 50 . Dog clutch 66 has a dog face 67 that bears against dog face 69 on end cap 34 when upper mandrel 50 is raised in the hole. Wings 72 secured on pins 76 in the upper mandrel 50 are operable by fluid pressure in bore 30 if upper mandrel 50 through opening 74 . Fluid pressure in bore 30 urges pistons 71 radially outward and causes wings 72 to swing outward on pins 76 into chamber 70 . Upon reduction of fluid pressure in bore 30 , wave springs 73 surrounding pistons 71 draw pistons 71 back into upper mandrel 50 . A spring (not shown) is also placed around wings 72 seated in groove 77 . Groove 77 is also formed in the outer surface of wings 72 and extends around upper mandrel 50 . The spring retracts wings 72 when the pressure in bore 30 is reduced and wings 72 are not held by frictional engagement with collar 84 .
Chamber 70 is bounded on its housing side by a sleeve 78 , which acts as a retainer for a piston actuation mechanism held between shoulder 80 on end cap 34 and shoulder 82 on housing 32 . The piston actuation mechanism includes thrust bearing 86 held between collars 84 and 88 , cam sleeve 90 and spring 92 , all mounted in that order on mandrel 32 . Cam sleeve 90 is mounted over a brass bearing sleeve 91 that provides a bearing surface for cam sleeve 90 . Spring 92 provides a sufficient force, for example 1200 lbs, to force cam sleeve 90 uphole to its uphole limit determined by the length of sleeve 78 , yet not so great that downhole pressure on upper mandrel 50 cannot overcome spring 92 . Spring 92 may be held in place by screws in holes 93 after spring 92 is compressed into position during manufacture, and then the screws can be removed and holes 93 sealed, after the remaining parts are in place.
Cam sleeve 90 is provided with an annular ramped depression in its central portion 94 and thickens uphole to cam surface 96 and downhole to cam surface 98 , with greater thickening uphole. Piston 60 is offset uphole from pistons 64 by an amount L, for example 3-½ inches. Cam surface 96 is long enough and spaced from the center of depression 94 sufficiently, that when cam sleeve 90 moves a distance L downward to the position shown in FIG. 10, piston 60 rides on cam surface 96 , while pistons 64 ride in the center of depression 94 . Cam surface 98 is long enough and spaced from the center of depression 94 sufficiently, that when cam sleeve 90 is urged uphole by spring 92 to the position shown in FIG. 2C or 8 C, pistons 64 ride on cam surface 98 , while piston 60 rides in the center of depression 94 . Thus, when cam sleeve 90 is forced downhole in relation to housing 32 , pistons 60 ride on uphole cam surface 96 , and are pressed outward into the well bore beyond the outer diameter of housing 32 , while pistons 64 may retract into annular depression 94 . When cam sleeve 90 is in the uphole position, pistons 60 are in annular depression 94 , while pistons 64 ride on downhole cam surface 98 . Pistons 62 will also ride on cam sleeve 90 , but are slightly offset downhole from piston 60 and so do not extend as far outward. Since cam surface 98 has a smaller diameter than cam surface 96 , the tool may move more readily in the hole when pistons 64 are extended for the straight ahead drilling position, and piston 64 and housing 32 act as a stabilizer. The stabilizer position or straight ahead drilling position of the pistons is shown in the end view FIG. 19 and the cross sections of FIGS. 5 and 6. The offset drilling position of the pistons is shown in the end view of FIG. 18 and the cross sections of FIGS. 12-14.
An orientation system is also provided on rotary steerable drilling tool 10 . A sensor 102 , for example a magnetic switch, is set in an opening in upper mandrel 50 . A trigger 104 , for example a magnet, is set in end cap 34 at a location where trigger 104 will trip sensor 102 when mandrel 20 rotates in an on-bottom drilling position (either offset or straight). Snap ring 105 should be non-magnetic. A further sensor 106 is set in upper mandrel 50 at a distance below sensor 102 about equal to the amount upper mandrel 50 is pulled back as shown in FIGS. 2A-2D, which will be slightly greater than the distance L, for example 4 inches when L is 3½ inches. Trigger 104 will therefore trip sensor 106 when mandrel 20 is pulled back and jaw clutch faces 67 , 69 are engaged. This position allows the tool to be oriented with the MWD tool face. Sensors 104 and 106 communicate through a communication link, e.g. a conductor, in channel 105 with a MWD package in MWD tool 14 . Sensors 102 and 106 are thus sensitive to the rotary orientation of housing 32 in relation to mandrel 20 , and when trigger 104 trips one of sensors 102 , 106 , sends a signal to the MWD tool 14 that is indicative of the rotary orientation of housing 32 on mandrel 20 .
For drilling in the straight ahead position shown in FIGS. 8A-8D and 9 , mandrel 50 is set down on lower mandrel 52 so that shoulders 59 and 61 abut. Wings 72 are held in mandrel 50 , and spring 92 urges cam sleeve 90 to the position shown in FIG. 8B, so that pistons 64 are forced outward by cam surface 98 , and piston 60 lies in annular depression 94 . In this position, pistons 64 and thickened portion of housing 32 form a circular stabilizer and mandrel 20 rotates within housing 32 centrally located in the hole.
For drilling in the offset position, rotary steerable drilling tool 10 is altered in position as shown in FIGS. 10-14. Upper mandrel 50 is lifted off lower mandrel 52 until dog face 67 engages dog face 69 , and rotated at least 360 degrees to ensure engagement of faces 67 and 69 . The orientation of housing 32 in the hole can then be determined by MWD tool 14 if the engaging position of dog faces 67 , 69 is programmed in the MWD package. Housing 32 may then be rotated from surface using mandrel 20 into the desired direction of drilling in the offset drilling position. The drilling direction will conveniently coincide with the direction that piston 60 points. With dog faces 67 , 69 engaged, fluid pressure is applied from surface to bore 30 of mandrel 20 to force wings 72 into a radially extended position. Mandrel 20 , or more specifically upper mandrel 50 , since lower mandrel 52 does not move in this operation, is then moved downward. Upon downward motion of mandrel 20 , wings 72 drive cam sleeve 90 downward and lift piston 60 onto cam surface 96 , thus extending piston 60 outward, while piston 64 moves into annular depression 94 . The action of piston 60 bearing against the wellbore places rotary steerable tool 10 in an offset drilling position using rotary stabilizer 17 as a rotating fulcrum. The ratio of the offset caused by pistons 60 , 62 to the offset at drill bit 16 is equal to the ratio of the distance of pistons 60 , 62 from rotary stabilizer 17 to the distance of drill bit 16 from rotary stabilizer 17 .
During straight ahead drilling, the location of housing 32 may also be determined by rotating mandrel 20 in housing 32 and taking readings from sensors 106 . The timing of the readings from sensor 106 may be used by the MWD package to indicate the location of housing 32 .
Immaterial modifications may be made to the invention described here without departing from the essence of the invention.
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The device provides a method for positioning the drill bit in a drilling operation to achieve small changes in hole angle or azimuth as drilling proceeds. Two different positions are available to the operator. The first is a straight ahead position where the tool essentially becomes a packed hole stabilizer assembly. The second position tilts the bit across a rotating fulcrum to give a calculated offset at the bit-formation interface. The direction that the bit offset is applied in relation to current hole direction is controlled by positioning the orienting pistons prior to each drilling cycle, through the use of current measurement-while-drilling (MWD) technology. Components of the tool comprise a MWD housing, upper steering and drive mandrel, non-rotating position housing, lower drive mandrel splined with the upper mandrel, rotating fulcrum stabilizer and drill bit.
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BACKGROUND OF THE PRESENT INVENTION
The present invention relates to heat shields and it is concerned particularly, but not exclusively, with heat shields for use in metal processing.
For instance, in the processing of a hot steel strip in a rolling mill, a hot product is taken through several working stages to produce a finished strip. The metallurgical qualities and gauge of the finished strip are closely related to the accurate control of the temperature of the material during the hot rolling process. However, due to heat losses occurring through radiation and convection it is extremely difficult to control the temperature through its various working stages which may require some time delay between stages thereby resulting in the product not having its required rolling and finishing temperatures.
Attempts in various forms, such as aluminum reflectors or heat insulating panels located along the delay table of a finishing mill have been used to reduce the heat losses from the surfaces of a hot product. These attempts have serious limitations which as to the reflectors are discussed in the background portion of Laws, U.S. Pat. No. 4,463,585, which is referred to herein for providing additional background information for a better understanding of the present invention.
As mentioned in this '585 patent, one type of heat insulating panel has a heat insulating core and a flat cover plate forming a main face of the panel; and as disclosed in this same patent, another type of heat insulating panel provides for relative thermal expansion of a thin, flat plate with respect to the core. In both types, the entire outer surface of the plate is directly exposed to the heated object and the plate is backed up by insulation. Also, both types are adapted so that the thin flat plates are temperature resistant material which absorb and then radiate heat back to the heated object or product. It is mandatory that the plate's dimension be such as to provide sufficient effective heat emissivity of its surface without melting and its temperature be able to quickly rise to closely approach the temperature of the product to re-radiate the heat and reach thermal equilibrium with the product.
It is therefore an object of the present invention to provide a re-radiating heat shield having a surface area with a substantially high heat emissivity and thermal capacity substantially equivalent to the panels of the present designs however commencing to re-radiate heat and approach thermal equilibrium with the heated product in a much quicker period of time with a less temperature drop in the heated product compared to the panels of the present designs.
It is a further object of the present invention to provide a heat shield for re-radiating heat comprising thermal insulating material having a number of closely adjacent co-extending sections provided with one or more holding surfaces formed by said adjacent sections, thermal absorbing material having a portion directly exposable to a heat source which portion includes a series of relatively short co-extending surfaces, said thermal absorbing material also including for each said short surface a substantially co-extending longer surface arranged not to be directly exposed to said heat source, said longer surfaces of said thermal absorbing material arranged to enwrap at least a portion of a different one of said co-extending sections of said thermal insulating material and restrained by said holding surfaces of two adjacent sections of said insulating material, wherein the nature and thermal mass of said thermal absorbing material and the nature and relationship of said thermal insulating material relative thereto greatly increases the re-radiating thermal characteristics of said thermal absorbing material.
More particularly, the present invention provides a design for a re-radiating panel having a sheet of refractory fiber material arranged in a sinuous manner to form a block, and a relatively thin sheet of heat storing material such as stainless steel arranged adjacent to the sides of the fiber sheet such that it conforms to the fiber sheet's sinuous configuration with portions of the stainless steel sheet doubling over into folds and which folds fit tightly in the folds of the fiber block for support and strengthed thereby and where heat is stored and other relatively shorter portions of the stainless steel sheet being exposed to the atmosphere.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic of a first embodiment of the present invention positioned above a heated product; and
FIG. 2 is a partial schematic of a second embodiment of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring first to FIG. 1, there is shown a heat re-radiating panel 10 of the present invention. This panel 10 may be substituted for the panels with slight modifications as those disclosed in U.S. Pat. Nos. 4,343,168 and 4,463,585; the latter patent being previously mentioned, or may be used for a lining of a sidewall or roof of a furnace or of some other high temperature equipment such as hot strip coilers now being employed in front of the finishing stand of a hot strip mill. For explanation purposes herein panel 10 will be discussed with reference to a delay table between a roughing train and a finishing train of a hot strip mill.
Below re-radiating panel 10 is a hot transfer bar 12 supportable by the delay table and having a temperature of approximately 2000° F., which may be either steel or aluminum, and whose thickness is designated as T.
Panel or block 10 comprises an insulating blanket 14 made of refractory fibrous materials, such as chromia-alumina-silica, alumina-silica compositions and zirconia compositions which materials have the ability to withstand high temperatures. Block 10 is preformed by folding insulating blanket 14 in a sinuous manner to form a plurality of even length adjacent layers 16. Details of its construction and operation of such a ceramic insulating blanket 14 and its particular mounting features which may be used in the present invention are further disclosed in Byrd, Jr. U.S. Pat. Nos. 4,001,996 and 4,123,886 which are incorporated herein by reference.
Wrapped around the curves of adjacent layers 16 on the side of block 10 facing toward transfer bar 12 is an extremely thin sheet 18 of ferrous material having the characteristics to both resist high temperatures and to retain heat; for example, stainless steel. Naturally, the thermal capacity of the stainless steel sheet is proportional to its thickness t indicated on the left hand side in the Figure. Thickness t of sheet 18 would have a substantially smaller dimension than the thickness T of transfer bar 12. Ideally, this ratio being 1 to 500 or greater, that is, the thickness of sheet 18 would be approximately 1/500th or less of the thickness of transfer bar 12. This ratio permits the heat from bar 12 to sheet 18 to be quickly transferred by radiation and convection, more about which will be discussed shortly.
Sheet 18 extends around the outer edges of block and wraps around and adheres to the layers 16 to fit a distance D into the folds 20 of each adjacent layer 16 and to create an effective re-radiating area around the curved sections of two adjacent layers L1, L2 of blanket 14 which re-radiating area is exposed to the atmosphere and as FIG. 1 shows directly above transfer bar 12. The sheet's adherence to the surfaces of blanket 14 is done through any suitable means, preferably an adhesive substance. Folds or double layers 22 of stainless steel sheet 18 act as heat accumulators, more about which will be discussed shortly.
In packaging and installation, block 10 is normally held together through bands (not shown) which wrap around block 10 with sheet 18. Thereafter, these bands are removed, whereby upon the transfer of heat from transfer bar 12, each layer 16 expands toward its adjacent layer 16 to snugly and securely hold fold portions 22 of stainless steel sheet 18 in folds 20. This holding aspect is augmented, as noted earlier, by the curved form of the sections of the exposed portions of the sheet 18 and by the folds of the sheet fitting tightly in the folds of the fiber block. Block 10 is secured in place by its mounting member 21 through suitable means to an overhang member (not shown).
The greater the ratio of bar thickness T to sheet thickness t, the less heat is required to heat the sheet 18, and therefore, since heating is a function of time, the quicker stainless steel sheet is able to return the heat to transfer bar 12. The heat from bar 12 is transferred into sheet 18 by radiation and convection and this heat in turn is conveyed by conduction into folds 22 of stainless steel sheet 18. The amount of heat stored in folds 22 of sheet 18 in addition to its thickness depends upon its total length sinuously wrapped around block 10, and naturally, the thermal efficiency of insulating blanket 14.
Also, it is important to note the substantial greater length D of the heat storable surfaces of the folds 22 as compared with the much shorter exposed surfaces of the sheet 18, which ratio in its illustrated form is somewhat greater than 2 to 1, and which may be as high as 10 to 1, and may exceed 5 to 1 in certain applications.
In use, a transfer bar 12 having a temperature of approximately 1900° F. is caused to travel adjacent to the outer face of re-radiating block 10. Its front end will first cool at almost the same rate it would achieve if exposed to the atmosphere. Since sheet 18 is extremely thin, its temperature will quickly rise to closely approach the bar temperature at say 1800° F. with a drop of approximately 20° F. in bar temperature, all the while the heat being conducted into folds 22 of sheet 18.
The relationship between the amount of heat used for re-radiation and the amount of heat accumulated in the folds will be determined as a function of temperature and the geometry of transfer bar and the time delay between sequential bars. This relationship can be estimated by providing a predetermined depth D of folds 22 of stainless steel sheet 18.
A still higher degree of heat can be retained in folds 20 by providing rod-like electrical heating elements 24, embedded in sheet folds 22 as shown in FIG. 2. These elements 24 are one of several well known types and may be used when the time delay between subsequent transfer bars is excessive or the ratio of the thickness of bar 12 to the thickness of sheet 18, is relatively small, i.e. more time is needed for the sheet to heat up initially due to the fact that the transfer bar is radiating heat to the sheet at a slower rate of speed than if the thickness of the bar were greater.
Since heat loss into sheet 18 is minimized by the thermally insulating blanket 14, the emissive area of sheet 18 almost immediately begins to re-radiate heat and approach thermal equilibrium with bar 12 somewhere in the range of 1700° to 2000° F. During gap time between bars, the excessive heat stored in folds 22 of sheet 18 will be transferred to those portions exposed to bar 12. Therefore, when the bar 12 exits from under re-radiating block 10, those portions of sheet 18 exposed to bar 12 remain at substantially the same previously attained equilibrium temperature for a much longer period of time compared to the thicker flat plate construction of the present designs identified above, which means that when the next hot bar comes under heat shield 10, a shorter length of its leading end will cool than that of the previous bar since heat is still retained in the effective radiating area of heat shield 10.
Heat is re-radiated from sheet 18 to the new bar, and thermal equilibrium between sheet 18 and the new bar is attained much more quickly than what occurred in the previous transfer bar which was positioned under heat shield when it was cold. Minimizing the time delay between sequential transfer bars positioned beneath heat shield can obtain a constant equilibrium temperature between bar 12 and sheet 18. The present invention also allows a time delay between sequential transfer bars to be extended for a longer period of time than what is permissible with the heat shields of the present designs with either the same or greater amount of heat re-radiating efficiency.
The present invention has been discussed in the embodiment where a heat shield arrangement is located above the transfer bar; however, it is to be understood that in accordance with the teachings of the aforesaid patents, that such a heat shield arrangement can have panels disposed below the path of transfer bar, or that a heat shield panel can be disposed both above and below the transfer bar's path of travel; or there may be other embodiments and uses which fall within the spirit and scope of the present invention as defined by the following claims.
In accordance with the provisions of the patent statutes, I have explained the principle and operation of my invention and have illustrated and described what I consider to be the best embodiment thereof.
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A refractory block design for re-radiating a substantial amount of heat losses back to a heated product thereby substantially maintaining its required temperature. A relatively thin sheet of stainless steel, i.e. the ratio of the thickness of the sheet being approximately 1/500th of the thickness of the heated product, is wrapped in a sinuous manner around one side of a refractory fiber block arranged in a similar sinuous manner to tightly fit into the folds of the block for storing heat, and radiating heat back to the heated product when thermal equilibrium therebetween is reached.
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CROSS-REFERENCE TO A RELATED APPLICATION
This application claims priority of previously filed U.S. Provisional Patent Application Ser. 60/486,372 filed Jul. 11, 2003. The disclosure of the provisional application is incorporated herein by reference.
BACKGROUND
The disclosure relates generally to the field of sample assaying devices, which can be used to manipulate samples, including samples used to assay for analytes, especially drugs of abuse, antibodies, antigens and biological moieties such as steroids and glucose. In particular, the disclosure relates to improvements in assay device design that provide and true positive and negative control for each analyte of interest, to be used in a clinical setting.
In the drug of abuse testing industry, various governmental agencies and professional organizations, such as but not limited to CLIA CAP, COLA and JCCHO, have initiated regulations to ensure quality control and standardization of testing with point of care devices. For example, these agencies and organizations may require certain positive, negative or procedural controls to be run at the beginning of the day, or the beginning of a new lot of devices. No point of care test devices currently on the market have true positive and negative controls, to which the test results obtained with the test sample can be compared, creating an ongoing and existing need.
SUMMARY
As a non-limiting introduction to the breath of the present disclosure, the present disclosure includes several general and useful aspects, including:
A device for detecting the presence of an analyte of interest in a sample of a subject in need there of, comprising: a sample test strip, for assaying for the presence or absence of an analyte of interest in an aliquot of the sample of the subject; a positive control, comprising at least one test strip and a positive control solution further comprising the analyte of interest and a buffer; and a negative control, comprising at least one test strip and a negative control solution further comprising a buffer; wherein said positive and negative controls indicate the correct functioning of the assay for the analyte of interest.
A method for detecting an analyte of interest in a sample of a subject in need there of, comprising: providing a sample of the subject; providing the test device of claim 1 or claim 9 , applying an aliquot of said sample to said sample test strip; applying an aliquot of said positive control solution to said positive control test strip; applying an aliquot of said negative control solution to said negative control test strip; incubating said test device; reading said test results and said positive and negative control results; and confirming the correct functioning of said test device by comparing said test results to said positive and said negative control results.
A kit for testing a sample for the presence of an analyte, comprising: the test device of the present disclosure, positive and negative control solutions, and instructions for the use of the test device and the control solutions.
The present disclosure includes, but is not limited to, an assay device able to detect or measure, for example, chemically or immunologically, analytes in a fluid sample, especially those assay devices with positive and negative controls. In particular, the assay device may be used to detect or measure drugs of abuse in a fluid sample, especially a biological fluid sample, such as urine or blood, collected from a subject in need of testing.
The present disclosure includes a variety of other useful aspects, which are detailed herein. These aspects of the disclosure can be achieved by using the articles of manufacture and compositions of matter described herein. To gain a full appreciation of the scope of the present disclosure, it will be further recognized that various aspects of the present devices and methods can be combined to make desirable embodiments. In addition, a variety of other aspects and embodiments of the present disclosure are described herein.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing summary, as well as the following detailed description may be better understood when read in conjunction with the accompanying drawings, which are incorporated in and form a part of the specification. The drawings serve to explain the principles of the invention and illustrate embodiments of the present invention that are preferred at the time the application was filed. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown.
The accompanying drawings, which are incorporated in and form a part of the specification, illustrate the embodiments of the present invention and, together with the following description, serve to explain the principles of the invention. For the purpose of illustrating the invention, there are shown in the drawings embodiments which are presently preferred, it being understood, however, that the invention is not limited to the specific instrumentality or the precise arrangement of elements or process steps disclosed.
In the drawings:
FIG. 1 depicts one embodiment of the present device. FIG. 1 shows a, bi-fold test device in an open position, illustrating the test face of the device. In this embodiment, one or more control lanes are located on the first panel 110 of the test device. Similarly, one or more sample test lanes are located on the second panel 120 of the test device. The test device is used in this open position.
FIG. 2 is an exploded view of the embodiment of the instant device illustrated in FIG. 1 .
FIG. 3 illustrates one embodiment how the control cassette 104 fits into the top cover 102 of the first panel 110 of the device shown in FIG. 1 .
FIG. 4 shows the device of FIG. 1 in a closed position.
FIG. 5 shows one example of indicia which might be used on the test face of the device illustrated in FIG. 1 . For example, control indicia 520 may appear on the face of the first panel 110 . In another example, test indicia 510 may appear on the second panel 120 .
FIG. 6 is an example of what control and test results might look like if the subject providing the test sample had been using cocaine, pot and ecstasy.
FIG. 7 illustrates various sides of the device of FIG. 1 .
FIG. 8 illustrates another embodiment of the present device, a tri-fold test device, in a partially opened position.
FIG. 9 shows the embodiment of FIG. 8 in the closed position.
DETAILED DESCRIPTION
Definitions
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Generally, the nomenclature used herein and the manufacture or laboratory procedures described below are well known and commonly employed in the art. Conventional methods are used for these procedures, such as those provided in the art and various general references. Terms of orientation such as “up” and “down” or “upper” or “lower” and the like refer to orientation of the parts during use of the device. Where a term is provided in the singular, the inventors also contemplate the plural of that term. The nomenclature used herein and the laboratory procedures described below are those well known and commonly employed in the art. As employed throughout the disclosure, the following terms, unless other wise indicated, shall be understood to have the following meanings:
“Assaying” denotes testing for or detecting the presence of a substance or material, such as, but not limited to, a chemical, an organic compound, an inorganic compound, a metabolic product, a drug or a drug metabolite, an organism or a metabolite of such an organism, a nucleic acid, a protein, or a combination thereof. Optionally, assaying denotes measuring the amount of the substance or material. Assaying further denotes an immunological test, a chemical test, an enzymatic test, and the like.
A “reagent” can be any chemical, including organic compounds and inorganic compounds and combinations thereof. A reagent can be provided in gaseous, solid, or liquid form, or any combination thereof, and can be a component of a solution or suspension. A reagent preferably includes fluids, such as buffers useful in methods of detecting analytes in a sample or specimen, such as anticoagulants, diluents, buffers, assay reagents, specific binding members, detectable labels, enzymes and the like. A reagent can also include an extractant, such as a buffer or chemical, to extract an analyte from a sample or specimen or a sample collection device. For example, a buffer can be used to extract analytes from the sample or specimen, such as LPS from bacteria.
An “analysis device” or “assay device” is a device for analyzing a sample or specimen. An analysis device can be used to detect the presence and/or concentration of an analyte in a sample or specimen, or to determine the presence and/or numbers of one or more components of a sample or specimen, or to make a qualitative assessment of a sample or specimen. Analysis devices of the present disclosure include but are not limited to lateral flow detection devices such as assay strip devices, and columns.
A “lateral flow detection device” or a “lateral flow test device” is a device that determines the presence and/or amount of an analyte in a liquid sample or specimen as the liquid sample or specimen moves through a matrix or material by lateral flow or capillary action, such as an immunochromatographic device. A lateral flow detection device may be used in a substantially vertical or a substantially horizontal orientation or in an orientation substantially between vertical and horizontal. Persons knowledgeable in the art commonly refer to a lateral flow detection device using terms such as “immunochromatographic,” “dip sticks,” “membrane technology” and “test strips.”
“Analyte” is the compound or composition to be measured that is capable of binding specifically to a ligand, receptor, or enzyme, usually an antibody or antigen such as a protein or drug, or a metabolite, the precise nature of antigenic and drug analytes together with numerous examples thereof are disclosed in U.S. Pat. No. 4,299,916 and U.S. Pat. No. 4,275,149. Analytes can include antibodies and receptors, including active fragments or fragments thereof. An analyte can include an analyte analogue, which is a derivative of an analyte, such as, for example, an analyte altered by chemical or biological methods, such as by the action of reactive chemicals, such as adulterants or enzymatic activity. An analyte may be a drug or drug metabolite, especially, but not limited to drugs of abuse, such as, for example amphetamines (speed), cocaine, THC (cannabis/pot), opiates (heroine), phencyclidine (PCP), methadone, benzodiazepines, methamphetamines (MDMA/ecstasy), phencyclidine (PCP/angle dust), tricyclic antidepressants and barbiturates.
An “antibody” is an immunoglobulin, or derivative or fragment or active fragment thereof, having an area on the surface or in a cavity, which specifically binds to and is thereby defined as complementary with a particular spatial and polar organization of another molecule. The antibody can be monoclonal or polyclonal and can be prepared by techniques that are well known in the art such as, for example, immunization of a host and collection of sera or hybrid cell line technology.
“Sample” or “specimen” may be used interchangeably. “Sample” or “specimen” denotes any material to be assayed for the presence and/or concentration of an analyte in a sample or specimen, or to determine the presence and/or numbers of one or more components of a sample or specimen, or to make a qualitative assessment of a sample or specimen. A sample can be the same as a specimen. Preferably, a sample is a fluid sample, preferably a liquid sample. Examples of liquid samples that may be assayed using an assay device of the present disclosure include bodily fluids including blood, serum, plasma, saliva, urine, ocular fluid, semen, and spinal fluid; water samples, such as samples of water from oceans, seas, lakes, rivers, and the like, or samples from home, municipal, or industrial water sources, runoff water or sewage samples; and food samples, such as milk or wine. Viscous liquid, semi-solid, or solid specimens may be used to create liquid solutions, eluates, suspensions, or extracts that can be samples. For example, throat or genital swabs may be suspended in a liquid solution to make a sample. Samples can include a combination of liquids, solids, gasses, or any combination thereof, as, for example a suspension of cells in a buffer or solution. Samples can comprise biological materials, such as cells, microbes, organelles, and biochemical complexes. Liquid samples can be made from solid, semisolid or highly viscous materials, such as soils, fecal matter, tissues, organs or other samples that are not fluid in nature. For example, these solid or semi-solid samples can be mixed with an appropriate solution, such as a buffer, such as a diluent or extraction buffer. The sample can be macerated, frozen and thawed, or otherwise extracted to form a fluid sample. Residual particulates can be removed or reduced using conventional methods, such as filtration or centrifugation.
A “control” is a portion of the assay designed to determine various aspects of progress of the assay conducted on a sample of a subject. For example, one might want to determine if the assay ran correctly, if the assay gave a correct answer, if the assay is complete, and the like. In some cases, a control is designed to provide an example of a positive or negative result, to which the person running the assay can compare the results obtained from assaying the sample of the subject. Controls may be run in various ways, which are well known in the art, depending upon the purpose of the control. For example, procedural controls generally indicate that the assay is complete. More specifically, in an immunoassay test strip, a control line may appear at the end of the test zone, to indicate that the sample has run far enough in the test strip and that the assay has been conducted for a long enough time. In another example, “reactive controls” may be run. Reactive controls may comprise extra lines on the test strip that mimic what the test result lines would look like if the test is either positive or negative, depending upon if the reactive control is either a positive or negative reactive control line. Generally, reactive controls are not considered to be true positive or negative controls. In yet another example, controls may be positive or negative. In the art, they may be referred to as “true positive controls” or “true negative controls,” in order to differentiate this type of control from the procedural or reactive controls. In the example of true positive and negative controls, two extra test strips are used, in addition to the test strip used to assay the subject sample. Positive and negative control solutions are also provided to the user. The positive control solution is similar to the sample solution and is spiked with a defined amount of the analyte of interest, or an analogue thereof, for which the subject sample will be assayed. The positive control solution will be applied to one of the test strips and will react with the appropriate reagents on the test strip to produce a positive test result. The negative control solution is substantially the same as the positive control, except that the negative control solution is not spiked with the analyte of interest. The negative control solution is applied to a second test strip. The negative control solution produces a negative result. The subject sample would be applied to the third test strip, in parallel with the positive and negative controls being applied to their respective test strips as described above. At the conclusion of the assay, the assay results of the subject sample could be compared to the assay results of the positive and negative tests, to confirm the positive or negative results of the assay of the subject sample.
Other technical terms used herein have their ordinary meaning in the art that they are used, as exemplified by a variety of technical dictionaries.
Assay Device
In the drug of abuse testing industry, various governmental agencies and professional organizations, such as but not limited to CLIA CAP, COLA and JCCHO, have initiated regulations to ensure quality control and standardization of testing with point of care devices. For example, these agencies and organizations may require certain positive, negative or procedural controls to be run at the beginning of the day, or the beginning of a new lot of devices. No point of care test devices currently on the market have true positive and negative controls, to which the test results obtained with the test sample can be compared, creating an ongoing and existing need. The present disclosure recognizes and provides a solution to this clear and ongoing need. In particular, the present device comprises on-board true positive and optionally true negative controls. More preferred, the present device comprises both on-board true positive and true negative controls. Most preferred, the present device comprises on-board true positive and true negative controls, having true positive and true negative control solutions. These positive and/or negative controls are assayed at the same time as the test sample, and the results of the test sample assay can be directly compared to the results of the positive and/or negative control assays, to ascertain if the test assay functioned correctly, the assay was conducted correctly, and/or if the results of the test sample assay were interpreted correctly.
Referring now to the figures, FIGS. 1 through 4 illustrate one embodiment of the present device, a test device 100 for detecting the presence of an analyte of interest in a liquid sample, such as, for example, urine or blood. FIGS. 1 , 2 and 3 show the test device in the open position. FIG. 4 shows the test device in the closed position, showing thumb tabs 410 . FIG. 2 and FIG. 3 are various explosions of the embodiment depicted in FIG. 1 and help to illustrate the assembly of the device of FIG. 1 . The structural characteristics of the present device will be described below. Then the function of the present device will subsequently be described.
FIG. 1 is a cartoon of one embodiment of the present device 100 , in the open position. The device comprises two or more panels 110 , 120 that are movably attached, so that the device can be opened and closed. In the embodiment shown in FIG. 1 , there are only two panels, a first panel 110 and a second panel 120 . The first panel 110 and second panel 120 are movably attached to each other, for example, but not limited to, by a hinge 130 . It should be appreciated that the quantity of panels can vary.
In certain embodiments of the present device, more than two panels may be attached using various attachment methods. For example, FIGS. 8 and 9 show a triple panel that closes by an accordion fold 820 . Various means, such as hinges, may be used to connect the panels and make it possible to open and close the device. In this embodiment of the present device, each panel 810 has one or more application wells 830 and one or more result windows 840 . Various aspects of sample and control arrangement are contemplated by the inventors. In one aspect, for example, the sample test strips may all be on one panel 810 , all of the positive controls on a second panel 810 , and all of the negative controls on a third panel. In an alterative aspect of the present device, one sample test strip, one positive control test strip and one negative control test strip may be arranged on each panel. Alternative arrangements of the sample and control test strips may also be used.
The housing of the present device can be manufactured with various materials. These materials can include but are not limited to metal, silicon, glass, ceramic, plastic and synthetic and natural polymers or any combination thereof. In one embodiment of the device, the housing can be manufactured from a polypropylene composite using an appropriate manufacturing method such as pressure injection molding or machining. Methods of manufacturing the housing can include but are not limited to milling, casting, blowing, and spinning.
As shown in FIG. 2 , a panel may be constructed a variety of ways. As an example, two preferred panel structures will be discussed. For convenience and clarity, the two types of structures will be referred to as “Insert Panel” and “Plain Panel.” In FIGS. 1 and 2 , the “Insert Panel” structure is illustrated by the first panel 110 of the present device. In contrast, the “Plain Panel” structure is characterized by the second panel 120 . For simplicity, each type of panel structure will be dealt with in turn.
Insert Panel Structure
As discussed above, certain embodiments of the present device comprise panels having an “insert structure” (see FIGS. 1 , 2 and 3 ). The first panel 110 , of the embodiment of the present device shown in FIGS. 1 and 2 , has and “insert structure.” As shown in the figures, the first panel 110 further comprises a first cover 102 and an insert 104 that fits snuggly into the first cover 102 . The use of inserts can facilitate the large scale manufacture, as separate portions of the device may be assembled separately and later put together in the final configuration. In additional embodiments of the present device, the insert 104 further comprises an insert face 140 and an insert back 220 . The insert face 140 has one or more insert result windows 160 as well as an identical number of insert application wells 162 . The insert face 140 and insert back 220 are fabricated so as to attach to each other to form a cassette that can hold test strips 230 . The insert face 140 and insert back 220 may be attached together by any convenient means, such as snapping, gluing or welding them together. As shown in FIG. 2 , the insert back 220 may contain structures that hold the test strips 230 in the correct location and orientation.
As discussed above, in certain embodiments of the present device, the insert 104 comprises one or more test strips 230 . The number of test strips 230 is the same as the number of results windows 160 and application wells 162 on the insert face 140 . For example, FIG. 2 shows and insert containing six test strips 230 , each with corresponding results windows 160 and application wells 162 . In the illustrated embodiment (see FIG. 2 ), three of the test strips 230 are dedicated to positive controls. The remaining three test strips 230 are used for negative controls.
As shown in the example illustrated in FIG. 1 , the insert face 140 of the first panel 110 has control solution wells 162 and control result windows 160 . FIG. 2 shows that the wells 162 and result windows 160 line up with the corresponding portion of the test strip 230 below. For example, the well 162 lines up with a sample application zone on the test strip 230 below. Similarly, the result window 160 lines up with the result zone of the test strip 230 below.
Plain Panel Structure
As discussed above, certain embodiments of the present device comprise panels having an “insert structure” (see FIGS. 1 , 2 and 3 ). The second panel 120 , of the embodiment of the present device shown in FIGS. 1 and 2 , has a “plain panel structure.” In additional embodiments of the present device, a panel 120 may comprise a back cover 240 and a face plate 150 . In this arrangement, the inner surface of the back cover 240 may have structures designed to hold a test strip 250 in the correct orientation for use. The face plate 150 , as shown in the present example, has one or more face plate application wells 172 and face plate result windows 170 . The face plate application wells 172 and face plate result windows 170 align with the test strips 250 , below the face plate 150 . Thus, a liquid sample may easily be applied to the sample application zone of the test strips 250 and the results of the assay may be viewed through the results windows 170 .
Test Strip Arrangements
FIG. 2 shows that each panel 110 and 120 , of the present device, further comprises one or more test strips 230 , 250 . Additionally, each panel 110 , 120 comprises a face plate 140 , 150 having sample application wells 162 , 172 and result windows 160 , 170 . The sample application wells 162 , 172 and result windows 160 , 170 are aligned with the test strips 230 , 250 below them. Depending upon the nature of the tests to be conducted, the analyte test strips may be grouped together, the positive controls may be grouped together and the negative controls may be grouped together. Alternatively, the analyte test strips may each be grouped together with their respective positive and negative controls. While the present disclosure contemplates various strip arrangement schemes, the arrangements of test and control strips chosen should facilitate the maximum ease of use and clarity of results.
Indicia
Indicia may be used to instruct the user how to perform the test and interpret the results. It should be appreciated that various types of indicia can be used, and that the indicia is not limited to alpha-numeric characters. In the embodiment shown in FIG. 5 , the tests are arranged so that the controls 520 are grouped together on a first panel and the sample assay tests 510 are grouped together on a second panel. Further in this example, the positive controls are on the left-hand side to the first panel, with each test strip testing for 3 drugs (denoted by AMP, COC, and THC; BZO, TCA and BAR; and MDMA, OPI and PCP) and a procedural control (denoted by CTL). As indicated below each positive control results window, three drops of the positive control solution should be placed in the positive control wells. Similarly, the negative controls are grouped on the right-hand side to the first panel. The indicia next to negative control results windows are the same as those next to the positive control results windows. However, the indicia below the negative control result window tell the user that they should add 3 drops of the negative control solution to the negative control wells. The sample assay test result windows, on the second panel, are labeled in the same manner as the positive and negative control windows (above). Here, three drops of the sample, such as urine or blood from a patient, are added to each sample application well.
FIG. 6 shows what test results might look like, following the procedures for testing a sample for the presence of drugs of abuse. In this example, the assays conducted (except for the procedural controls, CTL) are competitive immunoassays. This means that a line appears when the test is negative. If the test is positive for a drug, no line will appear where one should be, according to the indicia next to the results windows. Accordingly, all of the positive controls shown in FIG. 6 have no lines. Further, negative control test results appear as bands or lines, possibly of varying intensity or width, in the negative control result windows.
An example of sample test results are shown in the second panel (lower half of FIG. 6 ). In this example, there is no line for COC, THC or MDMA. But, there are lines for AMP, BZO, TCA, BAR, OPI and PCP. A technician testing a person's urine for the presence of drugs of abuse would interpret these test results to indicate that the person giving the urine sample had used cocaine (COC), pot (THC) and ecstasy (MDMA) recently.
Unlike the true positive and negative controls, the procedural controls (CTL) are sandwich immunoassays to an analyte unrelated to the analyte(s) of interest. Therefore, the procedural controls (CTL) produce a line for a positive result. Furthermore, no line is produced for a negative procedural control result. The procedural control (CTL) simply indicates if the applied sample or control solution ran a far enough distance through the test strip.
Test Strips
The test strips used in the disclosed device can be of any assay element known in the art and preferably comprises at least one lateral flow detection device such as an assay strip or test strip. Such lateral flow detection devices include, but are not limited to: immunoassays, chemical assays and enzymatic assays commonly known in the art, such as but not limited to, single antibody immunoassays, multiple antibody immunoassays, sandwich immunoassays, competitive immunoassays, non-competitive immunoassays and the like, including assays that utilize horseradish peroxidase, alkaline phosphatase, luciferase, antibody conjugates, antibody fragments, fluorescently tagged antibodies, modified antibodies, labeled antibodies, antibodies labeled with colloidal gold, antibodies labeled with colored latex bead, and the like, which are commonly known in the art. Examples of some assay strips that can be incorporated into the present device can be found in the following US patents: U.S. Pat. No. 4,857,453; U.S. Pat. No. 5,073,484; U.S. Pat. No. 5,119,831; U.S. Pat. No. 5,185,127; U.S. Pat. No. 5,275,785; U.S. Pat. No. 5,416,000; U.S. Pat. No. 5,504,013; U.S. Pat. No. 5,602,040; U.S. Pat. No. 5,622,871; U.S. Pat. No. 5,654,162; U.S. Pat. No. 5,656,503; U.S. Pat. No. 5,686,315; U.S. Pat. No. 5,766,961; U.S. Pat. No. 5,770,460; U.S. Pat. No. 5,916,815; U.S. Pat. No. 5,976,895; U.S. Pat. No. 6,248,598; U.S. Pat. No. 6,140,136; U.S. Pat. No. 6,187,269; U.S. Pat. No. 6,187,598; U.S. Pat. No. 6,228,660; U.S. Pat. No. 6,235,241; U.S. Pat. No. 6,306,642; U.S. Pat. No. 6,352,862; U.S. Pat. No. 6,372,515; U.S. Pat. No. 6,379,620; and U.S. Pat. No. 6,403,383. Further examples of some assay strips that can be incorporated into the present device can be found in the following U.S. patent applications Ser. Nos. 09/579,672; 09/579,673; 09/653,032; 60/233,739; 09/915,494, 10/211,199 and 09/860,408.
Specimen
Any type of liquid specimen may be used with the present device, including liquid specimens of the nature and character as described above in the definition portion of this disclosure. Alternatively, the sample applied to the test strip of the present device may be derived from other types of specimens dissolved in an appropriate liquid, such as a buffer or water. For example, the specimen may be composed of fine powdery materials such as talc, carbon black, pharmaceutical preparations, or gases such as argon or methane. Additional specimens can include atmospheric specimens that can be assayed for particulates or radioactive isotopes such as radon.
In an alternative embodiment of the present device the specimen to be tested is a biological specimen. Such biological specimens include but are not limited to a sample from a subject such as an animal or a human. A sample from a subject can be of any appropriate type, such as a sample of fluid, tissue, organ or a combination thereof. The biological specimen can also be a sample of other biological material, such as plants, bacteria, cell or tissue cultures, viruses and prions, or food, including food such as material derived from plants or animals or combinations thereof. The sample can be processed prior to introduction into the assay device. In the alternative, a sample and reagent can be combined within a specimen collection container. Such reagents can be used to process a sample, such as digesting solid samples with appropriate reagents such as chemicals, such as acids or bases, or with enzymes such as proteases. Other reagents can be used to extract analytes from a sample, such as extraction of antigens from biological entities, such as antigens from etiological agents such as bacteria, parasites, viruses or prions such as known in the art.
The specimen can also be an environmental sample, such as a sample of soil, water, wastewater, landfill or landfill leachate.
While a number of different biological specimens are suitable for collection by the specimen collection container, commonly collected specimens are biological samples, including but not limited to fluid sample including urine, blood, serum, saliva, and semen, secretions including vaginal secretions, central nervous system fluids, lavages and the like.
Methods of Use
The present disclosure contemplates methods of use of the test device described supra. One embodiment of a present method for detecting an analyte of interest in a sample of a subject in need there of, comprises the following steps. First a sample, such as urine or blood, is collected from a subject. A test device of the present disclosure, such as one describe supra, is provided and an aliquot of the sample is applied to the sample wells of the test device. Next an aliquot of the positive control solution is applied to the positive control wells and an aliquot of the negative control solution is applied to the negative control wells. The test device is then incubated for an appropriate amount of time. The amount of time necessary to incubate the device is dependent upon the length of the test strips, the test strip design and components, and the characteristics of the subject sample used. However, since the consumer wants rapid results, the tests are usually designed to take only a few minutes to run. At the conclusion of the incubation period, the operator of the test can read the test results and compare the test results to the positive and negative control results. After reading the test results and confirming the correct functioning of the test device by comparing the test results to the positive and negative control results, the operator would report the results where and when appropriate, and dispose of the test device.
KITS
Another embodiment of the present disclosure is a test kit, for testing a sample for the presence of an analyte, such as drugs of abuse or metabolites. In preferred embodiments, the test kit comprises a test device of the present disclosure, as described supra, control solutions and instructions describing the correct use of the device. Different types of kits are contemplated by the present disclosure. For example, the needs of an employment drug testing site may be different from the needs of a doctor's office. The kit can be tailored to meet those needs. For example, kits purchased by an employment drug testing site may contain 20 test devices, 10 ml dropper bottles of the positive and negative control solutions and one set of instructions. In such a setting, the emphasis is on high through-put and one or two technicians would perform many tests each day. In this situation, the technicians could share the control solutions and might only read the instructions the first time that they used one of the devices.
In contrast, a doctor's office might use one of the test devices on an infrequent basis. In such a situation, different people might conduct the tests and need single devices packaged together with small dropper bottles containing only enough control solutions necessary for one device. In this kind of situation, it may be preferred to supply instructions packaged with each device and set of control solutions.
EXAMPLES OF USE
Drug Testing Prior to Employment
A manufacturing company has conditionally hired a new engineer. Prior to the first day of work, the engineer goes to a drug testing laboratory, where he is tested for illegal drugs. At the drug testing laboratory, the engineer produces a urine sample for the technician and then leaves the facility. The technician takes a drug of abuse test device of the present disclosure, opens it and places it on the bench top. Next, using a disposable transfer pipette, the technician applies three drops of the engineer's donated urine to each sample application well of the test device. Then she squeezes three drops of positive control solution, from the positive control solution squeeze bottle, into each positive control well. Similarly, she squeezes three drops of negative control solution, from the negative control solution squeeze bottle, into each negative control well. She sets a timer for five minutes and allows the test device to incubate on the bench top. At the conclusion of the incubation, the technician reads and records the test and control (positive and negative) results for each drug assayed. When she is finished, the technician disposes of the remaining urine and the used test device, and mails the results to the employer.
Bedside Drug Overdose Testing in the Emergency Room
In the emergency room, an unconscious teenager is brought in. Due to his vital signs, the doctors suspect that the teenager has been taking drugs. To determine what drugs the teenager has taken, the nurse obtains a test device of the present disclosure, pricks the teenager's finger with a lancet, removes a small amount of his blood, and applies the blood to the sample wells of the test device. Then the nurse applies a small amount of the included control solutions to the appropriate wells of the test device. After a short incubation period, the nurse reads the test results and determines that the teenager has over-dosed on ecstasy. The nurse reports the results to the doctors, who proceed with the appropriate ecstasy overdose treatment for the teenager.
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The present disclosure includes but is not limited to an assay or test device, such as an immunological assay device, with positive and negative controls for each analyte of interest. In general, the device has a bi-fold, tri-fold or quarter-fold cassette, each folded side having one or more test strips contained therein. The device is compact and easily used by the worker. The present device is particularly useful in a clinical drug of abuse testing setting, in which the use of internal quality controls is regulated by the USCMS and the College of American Pathologists. In addition, the present device provides the advantages of ease of use, small size and reduced cost compared to other devices currently available on the market.
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CROSS-REFERENCE TO RELATED APPLICATIONS
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
BACKGROUND OF THE INVENTION
The present invention relates to clothes washing machines and, in particular, to a dispenser for such washing machines dispensing laundry aids such as bleach, softener, bluing or detergent.
Clothes washing machines suitable for residential or commercial use may provide a washtub into which clothes are loaded for agitation with water and detergent. In top loading washing machines, the washtub opens upwardly under a lid through which the clothes may be inserted. Front loading washing machines use a front opening washtub sealed by a front opening door through which clothes are placed. Both types of machines may have a console extending upward at the rear edge of the top surface of the machine. Washing machine controls, such as the cycle timer, water temperature, and fill height controls, may be located on this console for easy access.
Detergent may be added to the washtub at the beginning of the wash cycle, however, this is typically not the ideal time to add other laundry aids including bleach which may interact with the detergent decreasing its effectiveness or may be unnecessarily diluted and lost. Attending to the introduction of laundry aids at different times in the wash cycle is inconvenient to the consumer. Thus, there is considerable interest in dispensing systems that automatically add laundry aids to the washtub at different times during the wash cycle.
Some laundry aids, in particular fabric softener and detergent, are relatively viscous and have a tendency to clog simple valve systems. Accordingly, such as fabric softener may be dispensed through valve-less mechanisms. Fabric softener, for example, may be dispensed from a container attached to the agitator of the washtub. During the spin cycle, the fabric softener is released by centrifugal force which causes the fabric softener to rise up over the lip of its container. The container is made removable so that periodically it may be washed to remove residue resulting from incomplete release of the softener which returns to the bottom of the container at the end of the spin cycle.
Such a dispenser is only designed for top loading washing machines, and only suitable for laundry aids that may be added during the spin cycle. The location of this type of dispenser is inconvenient and consequently the consumer may overlook filling it.
Some of these problems are eliminated by the invention disclosed in U.S. Pat. No. 4,323,170 to Ikeda. The '170 patent teaches a dispenser that opens from the console of the washing machine. Valves are eliminated by the use of a “dump-cup” which receives laundry aids through a door in the console and tips to pour the laundry aids into the washtub. Tipping of the cup is controlled by the cycle timer providing flexibility in timing the introduction of the laundry aid into the wash. In the dumping position, a water stream may flush residue from the dump cup to minimize the build-up of sticky residue.
In order for the dump cup to be easily tipped and for its motion to be unobstructed, the dump cup is positioned near the bottom of the console and the laundry aids introduced by a vertically extending chute or funnel. Thus removed from the sight of the consumer, the dump cup may be easily overfilled if the consumer does not carefully pre-measure the laundry aid or if the consumer forgets that the dump cup has been previously filled. The dump-cup is shallow to minimize the amount of tipping necessary to empty it. This shallowness restricts the capacity of the dump cup for reasonably available areas within the console.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a system for release of a variety of laundry aids using an electronic valve system. When used as part of a console mounted dispenser, the valve system allows more conveniently sized accumulator cups whose interior volume may be viewed as they are filled by the consumer, eliminating the need for pre-measuring of the laundry aid. The valve system also allows a more compact installation of multiple accumulator cups next to each other, even in the console.
The valve system of the present invention also makes it possible for the cups to be removed for inspection and cleaning, if desired, and by allowing dispensing to occur from a lowermost drainage point in the cup, permits more complete drainage of that cup, reducing waste and build-up. The configuration of the valve system components permits self-cleaning of critical valve elements with a flushing water stream, if desired.
Specifically then, the present invention provides for a washing machine having a housing with an upper surface and a washtub positioned within the housing to receive clothing to be washed. A console extending upward from the upper surface of the housing includes a door and a laundry aid chamber is positioned within the console behind the door to be revealed when the door is open. A channel leads to the washtub and at least one electrically actuated valve is positioned between the laundry aid chamber and the channel, the valve operates, when closed, to cause the accumulation of introduced laundry aid in the laundry aid chamber as visible by a user through the door and when opened, facing the laundry aid accumulated in the laundry aid chamber into the channel.
Thus it is one object of the invention to permit convenient introduction of a laundry aid into a console-mounted dispenser without pre-measuring. Use of a valve, rather than a tipping of the accumulator cup, allows the dispensing cup to be sized and located so that its interior is visible to the consumer as a guide to proper filling.
The laundry aid chamber may include an outer chamber wall receiving at least one removable cup having an upper open end and a lower dispensing orifice. The cup may fit within the outer chamber wall so that a dispensing orifice engages with the electrically actuated valve. The electrically actuated valve communicates with the dispensing orifice to control the flow of laundry placed in the cup.
It is thus another object of the invention to provide for accumulator cups that may yet be removable for cleaning and yet are safely contained within the outer chamber walls for support, stability and the capture of spills and the like.
The valve may provide a valve head movable vertically from an upward closed position to a lower open position. The valve head may abut a bottom surface of the dispensing orifice to stop the flow therefrom when in the upwardly closed position. The laundry aid chamber and the removable cup may include interengaging detent surfaces holding the cup in place within the laundry aid chamber against the predetermined upward force.
It is thus another object of the invention to provide for a valve that allows easy removal of the cups and upon such removal, a cleaning of the valve seat of the valve such as an integral part of the cup.
The washing machine may include a second electrically actuated valve, and a second removable cup, the second removable cup also having an upper open end in a lower dispensing orifice. The second removable cup may fit within the laundry aid chamber adjacent to the first removable cup so that the dispensing orifice of the second removable cup engages with the second electrically actuated valve and wherein the second electrically actuated valve communicates with the dispensing orifice of the second removable cup to control the flow of laundry aid placed in the cup to the channel.
Thus it is another object of the invention to provide a dispensing system that allows a clustering of the dispensing cups for different laundry aids at a single convenient location, for example, the console. The ability to dispense the laundry aids by valves rather than dumping allows greater flexibility in the dimensions of the dispensing cups.
The cups may be of different colors and may include keys preventing engagement of the first cup with the second electrically actuated valve and vice versa. The cups may include graduations and may have different volumes related in ratio to a volumetric ratio between typical usages of predetermined laundry aids intended for the cups. The underside of the door may be exposed when it is open and may include indicia indicating the proper laundry aid for each cup.
Thus it is another object of the invention to identify the laundry aids to be placed in the adjacent cups and to assist the user in properly filling the cups both in type and amount of laundry aid.
The washing machine may include a bypass passage communicating between the outer chamber wall and the channel to the washtub and the cup may include at least one vertical wall fitting within the outer chamber wall that provides a chute between the vertical wall and the corresponding outer chamber wall and wherein the cup provides an overflow passage such as may be an orifice within the vertical wall of the cup communicating with the chute.
Thus it is another object of the invention to contain spills and overflow if the consumer overfills the dispensing cup.
The laundry aid chamber may include a flush channel communicating with a source of water and passing the water in the flush channel between the bottom surface of the orifice of the dispensing cup and the valve head of the electrically actuated valve when the valve is in the open position.
Thus it is another object of the invention to provide a simple valve mechanism that may remain free from accumulated residue of viscous laundry aids such as fabric softener.
The foregoing and other objects and advantages of the invention will appear from the following description. In this description, reference is made to the accompanying drawings, which form a part hereof, and in which there is shown by way of illustration, a preferred embodiment of the invention. Such embodiment and its particular objects and advantages do not define the scope of the invention, however, and reference must be made therefore to the claims for interpreting the scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a fragmentary perspective view of a top loading washing machine suitable for use with the present invention showing a console mounted laundry aid dispenser of one embodiment of the invention and a bottle of laundry aid positioned to be introduced into the laundry aid dispenser over a spill capture region;
FIG. 2 is an enlarged fragmentary perspective view of the dispenser of FIG. 1 with its door open such as reveals the internal volume of accumulator cups within the laundry aid dispenser chamber;
FIG. 3 is a cross-section along lines 3 — 3 of FIG. 2 showing the placement of the cup within the laundry aid dispenser chamber and a drain orifice in the cup such as forms a valve seat for a vertically movable valve head position therebelow and showing a bypass channel for overflow of laundry aids; FIG. 3 further shows laundry aid chamber graduations, a detent for holding the cup in position and key elements for preventing engagement of the cup in the wrong position;
FIG. 4 is a detailed cross-sectional view of the valve head of FIG. 3 showing an integral boot surrounding an actuator arm of a wax motor to wholly seal the wax motor from laundry aids;
FIG. 5 is a fragmentary cross-section taken along lines 5 — 5 of FIG. 2 showing the positioning of the two accumulator cups having different volumes at points along a sloping flush-channel such as removes residue from the valves when they are in their open position and assists in the transport of viscous laundry aid into the washtub;
FIG. 6 is a detail of one key of FIG. 3 showing a ward and pin system of the key of FIG. 3 for preventing engagement of the cups in the wrong position;
FIG. 7 is figure similar to that of FIG. 5 showing an alternative embodiment of the laundry aid chamber holding the accumulator cups and suitable for dispensing dry laundry aids.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to FIG. 1, a washing machine 10 includes a washtub 13 beneath an upper surface 12 having a door 14 opening to provide access to the washtub 13 . The door 14 is recessed within a well 16 in the upper surface 12 .
The well 16 is slightly larger than the door 14 so as to create a channel therebetween. The channel defines a spill capture region 20 in which spills from a bottle of a laundry aid 22 would be corralled by the well 16 to drain into the washtub 13 .
A console 24 extends upward from the rear edge of the upper surface 12 to present, on its front surface, controls 26 including a cycle timer control 28 of types well known in the art. Also positioned on the front surface of the console 24 is an access door 30 for a laundry aid dispenser of the present invention. The access door 30 is supported at an upper edge to swing about a generally horizontal axis between a closed position 32 (shown in solid lines) and an open position 34 (shown in phantom lines).
Referring now also to FIG. 2, the access door 30 opens to reveal upwardly open ends of accumulator cups 38 a or 38 b sitting within a laundry aid chamber 40 , both positioned beneath the door 30 and within the console 24 . The cups 38 a and 38 b are sized and held within outer chamber wall 42 of the laundry aid chamber 40 so that the internal volumes of the cups 38 a and 38 b are visible to a typical user standing toward the front of the washing machine 10 .
In this way the laundry aid 22 may be directly introduced into the accumulator cups 38 a and 38 b without pre-measuring. Graduations 48 in the form of notched, raised ribs extending upward from the bottoms of the cups 38 a and 38 b may provide further guidance indicating how full the cup should be filled. The graduations 48 may provide indicia for different amounts of laundry aid 22 to be introduced into the cups 38 corresponding to different sizes of the load. The graduations may alternatively use other marking techniques such as printed lines or the like.
As will be explained below, prior to the time at which the laundry aid 22 are to be introduced to the washtub 13 , no laundry aid 22 flows out of the accumulator cups 38 a and 38 b . This facilitates the use of the accumulator cups 38 a and 38 b and their graduations 48 in lieu of a separate measuring container.
The underside of the door 30 , when in the open position, displays labels 36 indicating the type of laundry aid 22 to be placed in the respective accumulator cups 38 a and 38 b . As depicted, a fabric softener may be placed in the leftmost accumulator cup 38 a and hence a portion of the door 30 over this cup 38 a includes the label 36 of “SOFTENER” and a downward extending arrow pointing to the accumulator cup 38 a . Conversely, a bleach may be placed in the rightmost accumulator cup 38 b and hence a portion of the door 30 over this cup 38 b includes the label 36 of “BLEACH” and a downward extending arrow pointing to the accumulator cup 38 b.
The labels 36 are in raised relief and hence the arrow may include drainage notch 44 to allow spills caught by the door 30 to drain downward into the respective cup 38 . For similar reasons, a notch 46 may be placed in the lower edge of the door 30 over each cup 38 a and 38 b.
Referring now to FIG. 3, each cup 38 has vertical walls 56 extending upward from a base 58 to open in an upper lip 60 . A front part of the upper lip 60 toward the front of the washing machine 10 extends forward over the front vertical wall 56 to provide a gutter 62 increasing the area of the lip 60 through which laundry aid 22 may be introduced into the cup 38 .
The front vertical wall 56 fits adjacent to an outer chamber wall 42 of the laundry aid chamber 40 but the rear vertical wall 56 is spaced away from its corresponding vertical outer chamber wall 42 to define therebetween a channel 63 . Overflow ports 50 may be positioned beneath the lip 60 near the rear vertical wall 56 and channel 63 to conduct excess laundry aid 22 , prior to its spilling over the lips 60 , through the overflow port 50 and the channel 63 through a sluice-way 65 beneath the base 58 , to a spout 64 leading to the washtub 13 . Thus overflow is conducted by the outer chamber walls 42 of the laundry aid chamber 40 to the washtub 13 .
Referring to FIGS. 3 and 6, the outer surface of the base 58 of each cup 38 includes a downwardly extending socket 66 engaging an upwardly extending pin 68 . The pins 68 for different cups 38 may include slots 70 located at different locations on the pin 68 and corresponding with wards 72 in the corresponding socket 66 . The effect of the locations of slot 70 and wards 72 is to provide a keying of particular cups 38 a and 38 b with only one location in the laundry aid chamber 40 . In this way, each of the cups 38 a and 38 b may have different volumes corresponding with their intended laundry aids 22 and have a unique color and possibly other indicia to indicate the type of laundry aid intended for the cups 38 . Preferably the color of the cup 38 corresponds with the color of its labels 36 and serving generally to remind the user of a particular type of laundry aid to be placed within the cups 38 a and 38 b.
The base 58 of each cup 38 includes an orifice 74 having a vertical axis and positioned at a lowermost portion of the inner surface of the base 58 , the latter which may be slightly concave to promote drainage towards this orifice 74 .
The underside of the orifice 74 provides a valve seat against which a valve head 78 may be pressed to retain the laundry aid 22 within the cup 38 or retracted to allow drainage of laundry aid 22 , from within the cup 38 through the orifice 74 , the sluice-way 65 into the spout 64 and washtub 13 .
Upward movement of the cup 38 under pressure from the valve head 78 is prevented by a retainer arm 52 extending inward and downward from an upper edge of 10 the rear vertical outer chamber wall 42 . A lower edge of the retainer arm 52 holds a pawl 96 engaging an upper lip 60 of the cup 38 . The retainer arm 52 may be pressed inward as indicated by arrow 98 to release the cup 38 so that it may be removed for washing or inspection. Removal of the cup also allows access to the sluiceway 65 and spout 64 for cleaning of debris and the like.
The retraction of the valve head 78 is effected by an actuator 80 seen also in FIG. 4 . The actuator 80 may be a wax motor of a type well known in the art in which an electric current introduced through terminals 82 of the actuator 80 heats a wax whose expansion actuates an internal piston (not shown) attached to an actuator arm 84 extending vertically upward from the actuator 80 toward the orifice 74 . The vertical orientation (and movement) of the actuator arm 84 allows larger tolerances in the vertical location of the cups 38 and hence the valve seat provided by the orifice 74 , incidental to the cups being removable. Vertical tolerances are accommodated by a spring loading of the actuator arm (not shown) providing slight over travel.
An upper barbed end of the actuator arm 84 may be captured within an upper portion of an elastomeric boot 86 . The lower edge of the boot 86 hermetically seals a rim of the actuator 80 surrounding the actuator arm 84 to prevent the infusion of laundry aids 22 into the joint between the actuator arm 84 and the body of the actuator 80 . The outer edge of the boot may have seals 88 which engage in a tubular orifice 92 in the bottom of the laundry aid chamber 40 beneath the cups 38 . The seals 88 prevent laundry aid from escaping from the laundry aid chamber 40 past the boot 86 .
The upper outer surface of the boot 86 provides an upwardly facing conical member 90 which, as described above, may engage, vertex first, with the orifice 74 to block or release laundry aids 22 , according to an electrical signal, is received by the actuator 80 .
In the preferred embodiment, the actuator 80 is attached to the cycle timer 28 (shown in FIG. 1) which may then precisely control the time of release of laundry aid from either of the cups 38 . Each of the cups 38 a and 38 b has its own actuator 80 and may receive a separate signal from the cycle timer 28 to release contained laundry aids 22 at different times.
Referring now to FIG. 5, each of the cups 38 a and 38 b may have corresponding orifices 74 a and 74 b opened and closed by corresponding valve heads 78 a and 78 b moved by corresponding actuators 80 a and 80 b . As described above, the actuators 80 a and 80 b are attached as shown in FIG. 3 to a tubular orifice 92 extending through the bottom wall of laundry aid chamber 40 such as forms part of the sluiceway 65 . This bottom wall of the laundry aid chamber 40 slopes downward from cup 38 b to 38 a and toward the spout 64 so as to promote drainage through the spout 64 .
Sluice-way 65 includes a water inlet port 100 opposite the spout 64 receiving a hose 102 providing a source of water, for example, the cold or hot water inlet valve or from a washing machine pump (not shown) that may accept a partial diversion of waters pumped by the washing machine through the sluice-way 65 to provide a flushing of viscous laundry aids into the washtub 13 for full dispersion. Significantly, when the valves formed by orifices 74 and valve heads 78 are open, the water through sluiceway 65 serves to clean the valve heads 78 and orifices 74 of residual laundry aid 22 . Further because the cups 38 a and 38 b consistently drain under the force of gravity, as opposed to intermittent drainage through centrifugal action over their upper edges, the cups 38 a and 38 b tend to remain much cleaner than prior art centrifugal dispenser techniques. Again the hermetic seal provided by the boots on the valve heads 78 a and 78 b prevent leakage out of the chamber area.
A temperature sensor 106 may be attached to a lower wall of the sluiceway 65 so that a probe 104 extends into the path of the water from the hose 102 . The temperature sensor may make use of any of a number of sensing devices including thermistors, resistive temperature detectors (RTD), thermocouples, bimetallic switches, and other similar devices known in the art. The temperature sensor 106 provides a measure of the temperature of the water from upstream hot and cold water valves (not shown but well known in the art) as mixed and to some extent accumulated within the turbulent flow of the sluiceway 65 to provide a consistent temperature signal. This temperature signal is sent to a control controlling the hot and cold water valves so as to provide closed loop control of water temperature.
It will be understood that the volume of cups 38 a and 38 b may be varied from one another by changing their cross-sectional diameter and/or height as provided by the sloping floor of the sluiceway 65 . In this way, different volume ratios of laundry aids can be matched by different ratios of the volumes of the cups 38 a and 38 b while providing that they are filled to substantially the same heights for convenience of the consumer.
Referring now to FIG. 7, in an alternative embodiment of the invention, the water inlet port 100 includes a branch 107 prior to entry into the laundry aid chamber 40 and sluiceway 65 . One portion of the branch passes through a restriction 108 and then into the sluiceway 65 as described above with respect to FIG. 5 . The second portion of the branch extends vertically into a tower passage 110 , such as may be molded or attached to an outer chamber wall 42 in one wall of the laundry aid chamber 40 , adjacent, in this example, to cup 38 c.
The restriction 108 is such that when water flows in hose 102 , a portion is directed up the tower passage 110 to an orifice 112 . The orifice 112 is aligned with a target opening in the upper edge of a vertical side wall of the cup 38 c adjacent to the orifice 112 so that a stream of water 115 is directed into the interior of the cup 38 c near the top of the cup 38 c . Dry laundry aid 116 , such as powdered detergent, is wet by the stream 115 to dissolve and pass through the orifice 74 c of the cup 38 c.
Because detergent is the first laundry aid typically added to the wash, the stream 115 may start at the beginning of the wash cycle when water is first provided from hose 102 and may continue during the entire wash cycle passing through the cup 38 c even after it is empty. For other laundry aids, a valve may be used to turn the stream 115 on and off.
It will be further understood that the present invention is not limited to a given number of cups 38 but may be used to provide a single cup or may be expanded to include three or more cups, for example, for powdered or liquid detergent, bleach and water softener as will be understood from the above description to one of ordinary skill in the art. In each case, the sluiceway 65 may be shared by each of the cups whose openings may be clustered conveniently for use by the consumer. Other locations of the cups, for example, under the door 14 as shown in FIG. 1 at location 120 or on the upper surface 12 at location 122 are also possible with the present design.
It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein, but that modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments also be included as come within the scope of the following claims.
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A laundry aid dispenser for a washing machine allows simple introduction of laundry aids into cups whose volumes are visible to the user and held within the console of the washing machine. A vertically oriented valve and flush chamber arrangement allows for the removal of the cups and the dispensing of viscous laundry aids such as fabric softener with reduced accumulation and buildup. The configuration also allows easy access to critical channels and parts of the dispenser as well as flexible electronic control of the dispensing times. Color-coding, keying and other indicia simplify the consumer's identification of the proper laundry aid for each cup.
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CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Priority is claimed from provisional patent application U.S. Ser. No. 60/541,787 filed on Feb. 4, 2004, and incorporated by reference herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] In general, the present invention relates to an apparatus, system and method of preserving and storing all production elements from oil and gas wells. More particularly, the present invention provides a storage vessel that can hold and capture under pressure all elements produced from a well and provide a means for separating the elements, such as but not limited to natural gas, water, oil, and associated condensate, in a usable and environmentally friendly system.
[0004] 2. Description of the Prior Art
[0005] In the oil and gas industry, a major concern facing the field is the ever growing and constant concern with environmental impact of oil and gas production coupled with the ever increasing need to maximize efficiency and recovery. Prior art methods that were perfectly acceptable just years ago are now politically and environmentally unfriendly as well as wasteful in hindsight. Whereas it was acceptable to allow by-products from well production to be released into the environment, it is not considered a viable economic or environmentally sound method to date.
[0006] Typically of wells in general, subterranean fluids and gas are moved from below ground to above ground wherein the subterranean fluids and gas may be separated for use. It is common for the subterranean fluid to have mixtures of oil and water intermixed with gas in greatly varying proportions depending on many factors of the geological formation, type of well and so forth. Depending on the well profile of amounts of water, gas and oil present in the production, different types of recovery systems are employed, but all share the need for a system to separate and store the varying amounts of elements produced.
[0007] It is common to allow oil recovered from wells to be stored in storage facilities or tanks that allow venting into the environment. Most known systems in oil and gas wells recover the oil from the well production and store it in tanks that are non-pressurized vessels with a venting system to the open air. It is understood that oil in liquid form continues to release gasses and that the grade of the oil is a direct correlation to its volatility and thereby, its release of gaseous elements. These tanks in the prior art are not designed to hold pressure and must have the ability to vent gasses that accumulate and pass from the stored oil to prevent the tank from rupturing, leaking, and so forth.
[0008] It is also well known to pass production from wells into separator units wherein the gas, water, and oil are essentially separated. The separator unit then generally sends the separated elements, such as water, gas, and oil, into respective containment systems for each element. The vertical or horizontal separator or production units were invented in the 1930's and have not been materially changed since that time. These prior art devices are satisfactory for wells that produce heavy crude oil and have little or no evaporative qualities, but do not adequately handle the gas condensate production existing in today's market.
[0009] The term condensate normally refers to the liquid that condenses from the natural gas and is physically separated in liquid form at the surface. The natural gas that leaves the subterranean reservoir is subjected to pressure reduction and to cooling, each of which causes condensation of the heavier and intermediate hydrocarbons. Condensates are actually crude oil in that they are the same material except that in the particular reservoir in which they are found they are associated with sufficient methane at high enough pressure to evaporate them into the gas phase until such time as the pressure is reduced.
[0010] Although the majority of gas is recovered and passed into a separate storage vessel or line designed to hold natural gas, the separated oil goes into storage tanks and, as discussed above, the gaseous elements continue to be released or evaporate from the accumulated oil even after the separation. These known systems obviously do provide for the recovery of the majority of gas from the well, but a percentage of potential energy is still lost through the venting in the oil storage.
[0011] Whereas some types of wells may primarily recover oil and others natural gas, it is common that wells that primarily produce natural gas will naturally need a system to remove accumulated subterranean fluids from the well to allow the gas to more easily flow and for overall well management. Plunger lift wells are well known in the art for natural gas production and the removal of subterranean fluids from the well.
[0012] It is also very common for plunger lift well systems to be used on mature and marginal wells where the cost of operating the well may be prohibitive considering the limited or marginally value of the recovered production. In these marginal type well operations, the fine line between cost of operation and profit makes all manners of recovery of hydrocarbons a potential make or break factor. There is an ever increasing need for making these marginal wells more profitable to lengthen their production lives as costs and value of oil increase globally.
[0013] Air pollution continues to gather global concern. Currently, operators of gas wells are allowing venting and evaporation of gas and condensate into the atmosphere every day, which is a continual major source of air pollution that should be abated. Further, land and creeks are being polluted by improper handling of oil and saltwater from wells. The land, creeks, lakes and air around oilfield locations can be protected by producing the wells into a closed pressure system which prevents the escape of pollutants especially into the air.
[0014] Still further, a common technique in the industry is to take the production from various wells and run the production lines to a centralized collection point. By means of example, a field of five wells may use a central collection point for separating, collection and so forth. This may be achieved by running the five individual production lines to one centralized location. This is common to reduce equipment needs at each of the individual well sites. A common drawback of doing such is that it does not allow for individual assessment of the production and/or production ratio from one specific well in the field. What is needed in the industry is an efficient, cost effective, and timely means to selectively monitor, test, and/or collect production from a specific well in a field that utilizes a common collection system or point.
[0015] It would therefore be desirable to have a mobile unit for collection, separation, and or production monitoring that may be easily transported from well to well without the need for permanently installation of equipment found in the prior art. Still further, it is desirable to provide a portable test means in general for well systems that use a common production collection system.
[0016] The above discussed limitations in the prior art is not exhaustive. Thus, there is a need for an apparatus, method and system to separate the varying components found during well production that maximizes recovery of all hydrocarbons and is environmentally friendly. The current invention provides an inexpensive, time saving, more reliable apparatus and method of near complete recovery of hydrocarbons from a well where the prior art fails.
SUMMARY OF THE INVENTION
[0017] In view of the foregoing disadvantages inherent in the known types of well production storage and separation methods now present in the prior art, the present invention provides a new and improved storage vessel and separation apparatus, system and method of use which may also be removably positioned to oil and gas wells. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved storage vessel and separator which may hold pressure to capture and retain all hydrocarbons produced from a well which has all the advantages of the prior art devices and none of the disadvantages.
[0018] To attain this, the present invention essentially comprises a vessel built to maintain accumulated pressure generally having a separator means for separating the elements from the production of a well. The vessel may be relatively mobile in nature, usable to a plurality of wells, and may further be constructed by converting existing equipment.
[0019] In a preferred embodiment, a pressure tested vessel will hold all of the produced liquids from a well, passing the natural gas to a sales line as it is separated from the fluids, allowing water to sink to the bottom of the vessel for drainage into a water storage tank for proper disposal, allowing condensate to form for recovery with any produced oil. The condensate and oil is stored until the vessel is nearly full, and then sold in the same manner as crude oil.
[0020] There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows may be better understood and in order that the present contribution to the art may be better appreciated. There are, of course, additional features of the invention that will be described hereinafter and which will form the subject matter of the claims appended hereto.
[0021] In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in this application to the details of construction 110 and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting. As such, those skilled in the art will appreciate that the conception upon which this disclosure is based may readily be utilized as a basis for the designing of other structures, methods, and systems for carrying out the several purposes of the present invention. It is important, therefore, that the claims be regarded as including such equivalent constructions insofar as they do not depart from the spirit and scope of the present invention.
[0022] Further, the purpose of the foregoing abstract is to enable the U.S. Patent and Trademark Office and the public generally, and especially the engineers and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of the technical disclosure of the application. The abstract is neither intended to define the invention of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the invention in any way.
[0023] Therefore, it is an object of the present invention to provide a new and improved storage vessel with a separator and method of using the same which may be easily and efficiently manufactured and marketed.
[0024] It is a further object of the present invention to provide a new and improved storage vessel with a separator and method which is of a durable and reliable construction and may be utilized with multiple wells.
[0025] An even further object of the present invention is to provide a new and improved storage vessel with a separator and method which is susceptible to a low cost of manufacture with regard to both materials and labor, and which accordingly is then susceptible to low prices of sale to the consuming industry, thereby making such tool economically available to those in the field.
[0026] Still another object of the present invention is to provide a new and improved storage vessel with a separator and method which provides all of the advantages of the prior art, while simultaneously overcoming some of the disadvantages normally associated therewith.
[0027] Another object of the present invention is to provide a new and improved storage vessel with a separator and method which maximizes condensate recovery and prevents the venting and or evaporation of usable hydrocarbons into the atmosphere.
[0028] Yet another object of the present invention is to provide a new and improved storage vessel with a separator and method that may be manufactured from existing equipment such as but not limited to tanks typically associated with large trucks used to carry gas and other materials under pressure on roadways.
[0029] An even further object of the present invention is to provide a new and improved storage vessel with a separator and method which improves and lengthens the productive lives of mature, marginal, and sometimes uneconomical wells. A preferred embodiment of the invention is especially useful when used in conjunction with a plunger lift system.
[0030] Still another object of the present invention is to provide a new and improved storage vessel with a separator and method which allows keeping volatile high gravity condensate under pressure to prevent escape of the aforementioned into the environment.
[0031] Yet still another object of the present invention is to provide a new and improved storage vessel with a separator and method which increases the BTU rating of gas and therefore the profitability of a well.
[0032] In another preferred embodiment, the invention may further provide a mobile system for utilization of monitoring, testing, collecting, and/or separating production from an individual well that may be part of a common collection production system from multiple wells in a field.
[0033] These, together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages, and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE PICTORIAL ILLUSTRATIONS GRAPHS, DRAWINGS, AND APPENDICES
[0034] The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed pictorial illustrations, graphs, drawings, and appendices wherein:
[0035] FIG. 1 is an illustration of a preferred embodiment of the invention generally depicting a pressure vessel and well operation or wellhead assembly for a plunger lift system.
[0036] FIG. 2 is an illustration of a preferred embodiment of the invention generally depicting a partial cross sectional side view.
[0037] FIG. 3 is an illustration of a preferred embodiment of the invention generally depicting a partial cross sectional side view.
[0038] FIG. 4 is an illustration of a preferred embodiment of the invention generally depicting a partial cross sectional side view.
[0039] FIG. 5 is an illustration of a preferred embodiment of the invention generally depicting a partial cross sectional side view.
[0040] FIG. 6 is an illustration of another preferred embodiment of the invention generally depicting a partial cross sectional side view in conjunction with a holding tank configuration.
[0041] FIG. 7 is an illustration of the preferred embodiment of the invention depicted in FIG. 6 generally depicting a partial cross sectional side view.
[0042] FIG. 8 is an illustration of the preferred embodiment of the invention depicted in FIG. 6 generally depicting a partial cross sectional side view.
[0043] FIG. 9 is an illustration of the preferred embodiment of the invention depicted in FIG. 6 generally depicting a partial cross sectional side view.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] Referring to the illustrations, drawings, and pictures, and to FIG. 1 in particular, reference character 10 generally designates a new and improved storage vessel with a separator apparatus, system, and method of using same constructed in accordance with the present invention. Invention 10 is generally used in a well 12 utilizing tubing 14 for the retrieval of hydrocarbons below the surface. Well 12 tubing 14 generally comprises a top 16 at a surface 18 where product 20 such as hydrocarbons and or other subterranean fluids are produced by the well 12 . Product 20 may be but is not limited to oil, crude oil, water, salt water, gas, natural gas, condensate and so forth. The term product 20 may be generalized to mean all items, materials, and things that flow from or are produced by well 12 .
[0045] It is also contemplated that invention 10 may be utilized with a plurality of wells or other facilities and that well 12 as generally depicted and described is for purposes of illustration of a preferred embodiment. The term well 12 may be generalized to mean all sources or structures of product 20 . Furthermore, it is contemplated that invention 10 may be utilized for other well applications other than hydrocarbon retrieval. It is contemplated that invention 10 may be used for other applications where storage and separation under pressure may be desirable such as in chemical plant operations, food production operations and so forth.
[0046] Top 16 of well 12 may be wellhead assembly 22 for a plunger lift system as generally depicted and described. It is understood that other well 12 configurations may be utilized and that the illustrations and depiction are for a preferred embodiment and should not be considered limited to such. Furthermore, it is contemplated that invention 10 may be utilized in well 12 where sufficient bottom hole pressure obviates the need for a plunger. As generally depicted, product 20 flows from well 12 via production flow line 24 .
[0047] In a preferred construction, invention 10 may generally include vessel 26 that is constructed to hold pressure therein. Vessel 26 generally comprises an exterior 28 , an interior 30 , a production or product 20 inlet 32 , a lower fluid outlet 34 , a sales line 36 , a pressure safety release assembly 38 , and an access port 40 . Furthermore, vessel 26 may include a support structure 42 , an interior 30 pressure gauge 44 , a fluid 46 level indicator 48 , and agitator 50 .
[0048] In a preferred embodiment, vessel 26 may be constructed from a converted trailer tanker 52 such as typically associated with the trucking industry wherein the trailer portion containing a pressure vessel may be utilized. As such, tanker 52 may have its wheels removed and necessary elements converted. It is understood that the conversion of existing tanker 52 is not considered to be limiting. Other existing vessels may be converted, such as but not limited to railroad type tankers, or other vessels known in the transportation field. It is also understood that it may be desirable to utilize these existing types of transportation vessels wherein the mode of transportation, such as the wheels for roadways and/or wheels for railroad tracks, may be retained to allow vessel 26 to be relatively mobile in nature.
[0049] Referring now further to FIG. 1 and FIGS. 2-9 , vessel 26 may be of different sizes and configuration and should not be considered to be limited by the illustrations and examples. In a preferred embodiment, vessel 26 may have at least 10,000 gallon capacity or 238 BBL. Salvaged equipment as described above may include pressure testing, altering existing configuration to accept various drains, gauges, intake connections and other parts in accordance with the present invention. Vessel 26 may be of various bursting strength or pressure testing. In a preferred embodiment, bursting strength may be 500 psi. It is understood that greater or lesser amounts may be utilized. Likewise, vessel 26 may be of 60,000 gallon capacity and different configuration and wherein conduits, lines, valves, and so forth may be of varying size such as but not limited ½ inch line and 8 inch line. It is understood that various sizes and configurations are contemplated and that the foregoing are examples and not to be considered limitations.
[0050] Vessel 26 access port 40 may be a manhole type configuration to allow an operator or equipment into interior 30 . When prior equipment is utilized or in general, access port 40 should be of a nature to hold pressure. Further as a safety precaution or to generally act as a pressure relief for moving, accessing, and so forth, vessel 26 , pressure safety release assembly 38 may be provided wherein at a given pressure, a valve would open to allow venting of interior 30 . The pressure safety release assembly 38 may be set at a given pressure to open or further include a variable adjustment means for selectively altering the pressure value for opening. Likewise, interior 30 pressure gauge 44 may further include a control means to work in cooperation with pressure safety release assembly 38 .
[0051] Of note, it is understood that fluid 46 may be comprised of differing elements such as condensate 54 , saltwater or water 56 , crude oil or oil 58 . It is understood that typically water 56 will sink to a lower level than condensate 54 or oil 58 and thus allowing for a relative separation through gravity wherein the water 56 may be drained out of lower fluid 46 outlet 34 which may be relatively positioned at the bottom or lower portion or area of interior 30 of vessel 26 .
[0052] Furthermore, fluid 46 that may contain hydrocarbons such as condensate 54 and or oil 58 may then be retrieved out of vessel 26 after water 56 is first removed. This may be accomplished through lower fluid 46 outlet 34 or a separate outlet (not depicted). It is contemplated that water 56 may be passed into a container 62 for storage and that a conduit 64 may be dedicated to such from vessel 26 . It is also contemplated that condensate 54 and or oil 58 may also be stored in a stock tank container 66 (not depicted) and that a conduit 68 (not depicted) may be dedicated to such from vessel 26 . Both containers 62 and 66 may be a separate pressure capable vessel 26 . It is understood that invention 10 may utilize numerous or a plurality of vessel 26 .
[0053] Fluid 46 level indicator 48 may be of numerous configuration such as but not limited to a site tube, gauge, or other known means for determining the amount of fluid 46 accumulation in vessel 26 . It is contemplated that sensors (not depicted) may be utilized to notice an operator when water 56 may need to be removed, condensate 54 and or oil 58 is in sufficient quantity for an action of removal from the vessel 26 . It is also contemplated that other sensors may be utilized for communicating with an operator in regards to pressure amount.
[0054] Likewise, natural gas or gas 60 will generally rise and separate in interior 30 of vessel 26 . Sales line 36 may be utilized to allow gas 60 to flow from vessel 26 into a separate facility (not depicted). Sales line 36 may also be utilized for other elements other than gas 60 depending on the production from well 12 .
[0055] In accordance with a preferred embodiment of the invention, agitator 50 may be utilized to further enhance the separation of elements or product 20 . As product 20 enters the vessel 26 , it is contemplated that a spray type nozzle 70 may be used such that product 20 is forced into a spray wherein separation of elements may be achieved more efficiently. It is understood that a preferred embodiment of invention 10 may not include agitator 50 or that another configuration may be utilized to enhance separation as currently known in the industry. Furthermore, it is contemplated that the spraying, mixing, separating, and agitating of fluid 46 will further increase the BTU rating and therefore increase the value of the gas.
[0056] In another preferred embodiment, support structure 42 may include a jack 72 which may raise or lower vessel 26 . Jack 72 may be hydraulic but is not limited to such and may be used to facilitate the removal of fluid 46 wherein water 56 is removed at a lower point. Further, oil 58 and condensate 54 may also utilize the lowering feature.
[0057] Support structure 42 may further include a wheel assembly 76 as commonly found on an existing tanker 52 . It is contemplated that tanker 52 may be of numerous configurations and sizes, retain its mobile nature for transporting from well 12 to other wells. Further, it is understood that although the drawings may not depict the hitch mechanisms commonly associated with tankers 52 , they may be utilized for transporting via truck, tractor and so forth or removed if desired.
[0058] In another preferred embodiment, invention 10 may further provide a mobile system 78 for utilization of monitoring, testing, collecting, and/or separating production from an individual well 12 that may be part of a common collection production system from multiple wells in a field.
In Operation
[0059] In a preferred method of operation, invention 10 may include connecting vessel 26 with well 12 wherein product 20 from well 12 operation moves through production flow line 24 into vessel 26 through inlet 32 . It is understood that invention 10 should generally be a closed system where all material, air, things, fluid and so forth from well 12 are contained and move into vessel 26 . It is further contemplated that invention 10 may be a partially open system and that a preferred construction is a complete or nearly completely closed system trapping all elements produced from well 12 operations.
[0060] Product 20 flows into the interior 30 of vessel 26 and passes through agitator 50 . Agitator 50 disperses product 20 and separates the differing elements. As such, water 56 will collect at the bottom of vessel 26 and condensate 54 and oil 58 will generally stay on top of water 56 . Gas 60 will pass through sales line 36 .
[0061] At a desired amount or time, water 56 may be removed through lower fluid outlet 34 leaving condensate 54 and oil 58 to be collected for sale. Water 56 may be treated on site or removed to a secure location or container 62 .
[0062] It is further contemplated that well 12 function may be regulated with a pressure clock 74 working in conjunction with vessel 26 . Pressure clock 74 would allow pressure to fill in the vessel 26 and still allow well 12 operations.
[0063] Changes may be made in the combinations, operations, and arrangements of the various parts and elements described herein without departing from the spirit and scope of the invention. In a preferred embodiment, a pressure storage vessel with separation system may comprise a vessel capable of holding pressure having an interior; an access port for allowing a human into the interior of the vessel; a pressure relief valve that allows pressure to vent from the interior of the vessel; a production line inlet that allows production from a well to enter the interior of the vessel tanker; an agitator in the interior of the vessel wherein the agitator is connected to the production line inlet; a first outlet to let accumulated gas selectively flow from the vessel interior to a collection point; a second outlet to let accumulated fluid be selectively drained from the vessel; and a wheel assembly attached to the vessel for transporting the vessel. Further, the vessel may be a trailer tanker with wheels, further include a pressure gauge for determining the pressure in the trailer tanker, and a liquid level indicator for indicating the level of liquid in the vessel interior.
[0064] In a preferred embodiment of the invention, a method of converting a trailer tanker to a mobile pressure storage vessel with separation apparatus may comprise the steps of providing a trailer tanker having an interior, an exterior, and wheels; making an access port for a human to enter the trailer tanker; installing a pressure relief valve that allows pressure to vent from the interior of the trailer tanker; installing a production line inlet that allows production from a well to enter the interior of the trailer tanker; installing an agitator in the interior of the trailer tanker that connects to the production line inlet; installing a first outlet to let accumulated gas selectively flow from the interior of the trailer tanker to a collection point; and installing a second outlet to let accumulated fluid be selectively drained from the interior of the trailer tanker.
EXAMPLE 1
[0065] A small producing gas well 12 in Caddo County, Oklahoma was chosen for the experiment. The well 12 was connected to a low-pressure gas gathering system that provided natural gas to nearby homes and to peanut farmers in the area for heaters to dry the peanuts after being dug up and sorted. The gathering and distribution lines were made of PVC pipe with a bursting strength of 125 psi., and therefore the well 12 was not allowed to produce into the line at pressures above 65 psi. The invention 10 was therefore closely regulated and at times, somewhat restricted in productive capacity. The invention 10 performed very well until the bottom hole pressure depleted to the point that it could no longer run the plunger lift system, and the well 12 was then plugged and abandoned.
EXAMPLE 2
[0066] In another experiment, invention 10 was moved to another well 12 in Canadian County, Oklahoma. The well 12 had been purchased from the previous operator who had shut it in previously and was preparing to plug and abandon it as an uneconomical venture. Later, another operator re-established production and worked over the same producing intervals, including the installation of a plunger lift system. The well 12 produced volumes at a slightly higher rate than during the last few months before being shut in.
[0067] After replacing the worn plungers again, invention 10 was installed. The well 12 increased the gas and condensate volumes to a level above the original flowing rates when the well 12 was new and to rates seven times as high as the levels in previous years. To date, the well 12 has produced almost as much new natural gas as it did in its original 8.5 year life. Condensate is being saved under pressure and sold as volumes permit.
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The present invention essentially comprises a vessel built to maintain accumulated pressure generally having a separator means for separating the elements from the production of a well. The vessel may be relatively mobile in nature, usable to a plurality of wells, and may further be constructed by converting existing equipment. In a preferred embodiment, a pressure tested vessel will hold all of the produced liquids from a well, passing the natural gas to a sales line as it is separated from the fluids, allowing water to sink to the bottom of the vessel for drainage into a water storage tank for proper disposal, allowing condensate to form for recovery with any produced oil. The condensate and oil are stored until the vessel is nearly full, and then sold in the same manner as crude oil.
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FIELD OF THE INVENTION
[0001] The present invention relates to geophysical prospecting using seismic signals, and in particular an automatic method for determining the locations of the shallow inhomogeneities or obstacles (to be called diffractors or scatterers) that scatter back energy radiated from source to the recorded sections in 3-D marine surveys.
BACKGROUND OF THE INVENTION
[0002] In the field of geophysical prospecting, seismic signals are used to do 3-D seismic surveys of a predetermined area. However, problems arise in the collection of data due to the backscattering of energy from the shallow inhomogeneities or obstacles.
[0003] 1. Prior Art at Compagnie Generale De Geophysique
[0004] Compagnie Generale de Geophysique utilizes a process called Deterministic Diffractor Noise Reduction (DDNR) to remove the contribution of diffractor energy from the survey. DDNR involves identifying and picking travel times for each diffractor located at sea bottom. Once travel times are known for a diffractor, then its location can be calculated by assuming a speed of propagation, like 1500 m/s, for the medium. Data can then be flattened using travel times calculated for the diffractor and the flat component of energy (diffraction) can be attenuated using FK filter or Radon transform filter, as it is known in the art.
[0005] 2. Prior Art in the Industry
[0006] Fookes et al. (“Practical interference noise elimination in modern marine data processing,” Expanded Abstracts, 2003 SEG Annual Meeting) follow a method similar to Compagnie Generale de Geophysique DDNR method mentioned above: pick travel times and find the diffractor location that minimizes the error between calculated travel times and measured travel times. Upon determination of diffractor location, the data is flattened and flat events suppressed.
[0007] A use of coherency measurement is using semblance in stacking velocity analysis of seismic data and is done by Taner and Koehler (1969, “Velocity spectra—digital computer derivation and applications of velocity functions,” Geophysics, 34, 859-881). The use of other coherency measures than semblance for lateral coherency of events is also possible: energy normalized cross correlation sum, stacking power, or stacking amplitude are other possibilities. Key and Smithson (1990, “New approach to seismic-reflection event detection and velocity determination”: GEOPHYSICS, Soc. of Expl. Geophys., 55, 1057-1069.) derived their coherency measure from the eigenvalues of the problem at hand. Gulunay (1991, “High resolution CVS: Generalized covariance measure”, 61st Ann. Internat. Mtg: Soc. of Expl. Geophys., 1264-1267) studied the relationship of such coherency measures including the ones derived from semblance. Gonzalez-Serrano and Chon (“Migration velocity analysis in 3-D,” Expanded Abstracts, 1984 SEG Annual Meeting), Sicking (“Diffraction semblance for velocity and structure analysis,” Expanded Abstracts, 1987 SEG Annual Meeting), and VarWest et al. (“Relation between velocity fields and imaging in the presence of lateral velocity variations,” Expanded Abstracts, 1985 SEG Annual Meeting) use semblance analysis for prestack migration velocity determination. Landa et al. (“A method for detection of diffracted waves on common offset sections,” Geophysical Prospecting, 35, 359-373, 1987) use semblance analysis to find buried edges in x-z plane that cause diffraction under a 2-D seismic line (shooting and receiving along x direction, shots and receivers at the surface, z=0) using common offset data (x-t). Landa and Keydar (“Seismic monitoring of diffraction images for detection of local heterogeneities,” Geophysics, 63, 3, 1093-1100, May 1998) use semblance analysis to detect local heterogeneities (diffractors) buried under a 2-D section (x-z plane) using a source receiver configuration similar to the ones used in 2-D seismic recordings (shooting and receiving along x-z direction, shots and receivers at the surface, z=0). The paper discusses a “D-section” which is similar in concept to semblance scanning; however, D-section is done for diffractor buried in a vertical plane of a complex earth. U.S. Pat. Nos. 6,687,618 and 6,546,339 also address the use of semblance scan in geophysical processing using seismic signals.
[0008] Two papers by Blonk et al (1994, “Inverse scattering of surface waves: A new look at surface consistency”, Geophysics, 59, 6, 963-972 and 1995, “An elastodynamic inverse scattering method for removing scattered surface waves from field data”, Geophysics, 60, 6, 1897-1903.) address the issue of finding and removing such diffractors for land data but their method is based on “linearized elastodynamic inverse scattering theory” and involves consideration of temporal frequency, solution of linear systems with tools like conjugate gradient algorithm and is completely different from the time domain amplitude coherency approach of the arrival energy used in this invention.
[0009] It is an object of this invention to remove the energy from the survey that is contributed by the diffractor.
[0010] It is a further object of the present invention to eliminate the task or necessity of picking of arrival or travel-times or going into complex theoretical calculations as in Blonk et al (1994, 1995) papers for determination of diffractor locations.
SUMMARY OF THE INVENTION
[0011] Diffraction is a wave phenomenon where a source radiates energy to a medium and an obstacle in the medium scatters that energy back to an array of receivers placed in the same medium. Seismic energy radiated by air guns in a 3-D marine survey travels in water or shallow part of the seismic section and gets scattered by diffractors at the water bottom, contaminating the seismic sections. Materials left at the sea bottom, such as wellheads, shipwrecks, even outcropping geology, may act like diffractors.
[0012] The present invention eliminates the task of picking arrival times by judging the likelihood of a tested location to be a diffractor point by calculating coherency of arrivals from that point. The present invention preferably utilizes semblance scan as a coherency analysis tool to minimize the energy contributed to the survey by diffractors. Any of the aforementioned measures could be used for coherency calculation; however, semblance derived measures are the most advantageous. First, they are the most economical to use. For this reason, the present invention uses semblance as the coherency measure. Second, semblance is sensitive to the coherency of the event but not to its actual strength. For example, stack amplitude for a five-sample event with amplitudes (1,1,1,2,1) is 6/5=1.2 and its semblance is 0.9. Stack amplitude for (10,10,10,20,10) is 60/5=12 but its semblance is still the same and is 0.9. An event could be weak but it could be coherent while an event could be strong but it may not be coherent.
[0013] In the present invention, locations of each diffractor are determined by comparing the lateral coherency of the received amplitudes that each assumed diffractor position generates. That is, these are the locations that are in agreement with the travel paths observed on the seismic traces recorded. The amplitudes of the diffractions are picked from received traces at the travel times (or around the travel times) it takes the emitted energy by a source to travel from it to a diffractor and from a diffractor to a receiver. Many measures may be used for lateral (receiver to receiver) coherency, including semblance. Areas of the x-y plane that radiate back scattered energy from sources to receivers in a 3-D marine recording can be put into semblance scan to find out which of these locations are likely to be the diffractor locations (by attaching a semblance value to each point). For a given diffractor, the amplitudes picked to be put into the semblance calculation can come from the traces (source-receiver pairs) of one or many sources and one or many array of receivers (called cables or streamers). This allows points with large semblance to be picked, thereby eliminating the need for picking travel times for each diffractor. Once a diffractor location is known, then data can be flattened using sum of the travel times from source to diffractor and from diffractor to receiver and then applying one of the methods of prior art, such as FK filtering, Radon filtering, etc. to remove such energy contributed by this diffractor.
DESCRIPTION OF THE DRAWINGS
[0014] For further understanding of the nature and objects of the present invention, reference should be had to the following figures in which like parts are given like reference numerals and wherein:
[0015] FIG. 1 shows boat sail-line patterns on a typical 3-D marine survey;
[0016] FIG. 2 shows source-diffractor-receiver travel path;
[0017] FIG. 3 shows arrival times of diffractions that are received from a diffractor by a boat carrying five cables;
[0018] FIG. 4 shows scan range for a given cable;
[0019] FIG. 5 shows a semblance plot generated from 20 shots each with 8 cables, each cable with 120 traces;
[0020] FIG. 6 shows local maxima picker; and
[0021] FIG. 7 shows flattening a diffractor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] In seismic prospecting for oil and gas, a boat 10 pulls a set of receivers 15 ((x r ,y r ) positions) placed on structures referred as “streamers” or “cables”. The boat 10 has airguns (not shown but well known in the art) placed near it and these guns fire at certain intervals ((x s ,y s ) positions) creating a seismic disturbance that travels into layers of earth and is reflected from each layer and received by these receivers. Reflections generally come from vertical slices of earth, which are called “subsurface lines” or “common midpoint lines,” formed by the geometry of the recording. There are as many subsurface lines as there are cables. The boat 10 generally travels on a straight line to cover an area of interest and then turns back and places itself on the same course but with some lateral shift to produce more subsurface lines as shown in FIG. 1 . Surface lines may overlap. It is imperative that what is recorded represents reflections from strata, but there are many noise types recorded. Among them is the scattered energy from inhomogeneities at sea bottom or materials that are at the sea bottom as wells, wellheads, sunken ships, etc. The scattered energy from the inhomogeneities are what the present invention seeks to eliminate.
[0023] A 3-D marine survey is generally recorded with patterns depicted in FIG. 1 . A boat 10 pulling a number of streamers 15 starts from a point, like point 1 , and travels to point 2 . Direction from Point 1 to Point 2 could be any azimuth, i.e. not necessarily a south to north line. The boat turns at point 2 and travels until point 3 and makes another turn at point 3 . It then travels to point 4 and makes another turn. It travels to point 5 and then makes another turn, and so on. Therefore, slightly shifting rectangles defined by points (1,2,3,4), (5,6,7,8), and so forth, are formed.
[0024] In the present invention, the initial step in locating the diffractors is to determine the minimum x value, maximum x value, minimum y value, and maximum y value of the receiver coordinates for the whole survey, as shown in FIG. 1 . This is done by looking at the trace headers on the data. (A source receiver pair is called a trace.) These values are called: X′ min , X′ max , Y′ min , Y′ max , respectively. These values are then extended by an amount that a seismic wave can travel at the water velocity in the recording time. These new minimum and maximum values are called: X min , X max , Y min , and Y max , respectively. Then,
[0000]
X
min
=X′
min
−VT
[0000]
X
max
=X′
max
+VT
[0000]
Y
min
=Y′
min
−VT
[0000]
Y
max
=Y′
max
+VT
[0000] where V is the medium (water) velocity and T is the recording time.
[0025] X and Y grid sizes, dx and dy respectively, are chosen to scan this area. Grid size (scan increment) used is typically 25 m both in x and y. Practice shows that any scan increments lower than 25 m and scan increments as high as 100 m can be used. However, the finer the scan increment, the more accurate the location determination for the diffractors. Of course, the run time is the more expensive. Sampling coarser than 100 m is not expected to yield accurate travel times for flattening the data for purpose of noise attenuation.
[0026] Then, for each point (x d ,y d ) on the grid defined by:
[0000] x d =x min +( i− 1)*dx (i=1, 2, . . . , i max )
[0000] y d =y min +( j− 1)*dy (j=1, 2, . . . , j max )
[0000] where
[0000] i max =1+( X max −X min )/dx
[0000] j max =1+( Y max −Y min )/dy
[0000] a coherency value is calculated using amplitudes, a n , picked at the travel time (using Eq. 2) from some (or all) of the source-receiver pairs ((x s ,y s ) and (x r ,y r ) pairs) for which travel times are in the recorded range (i.e. scattered energy from diffractors far away will not reach a given receiver if its arrival time is greater than recording time.)
[0027] There are many coherency measures available in the prior art. As discussed in the background and summary of the invention, it is possible to use stack amplitudes, stack power, energy normalized cross-correlation sum, or semblance. This invention uses the conventional semblance defined by
[0000]
s
=
(
∑
n
=
1
N
a
n
)
2
N
∑
n
=
1
N
a
n
2
EQ
.
1
[0028] Semblance Calculation from a Single Time Sample Per Trace
[0029] If selectivity is desired, one can use functions of semblance as discussed by Gulunay, (1991). Some of the useful functions are:
[0000]
s
n
n
>
1
s
1
-
s
log
(
1
1
-
s
)
[0030] This invention preferably uses semblance (Eq. 1 or its smoothed version to be given in Eq. 4). Once such a semblance distribution is obtained,
[0000] S(i,j) (i=1, 2, . . . , i max , j=1, 2, . . . , i max )
[0000] then local maxima in this function can be found by requiring a point to be larger than all of the points in its neighborhood, (e.g. in a 100 m by 100 m part of the grid). Among all such points, the ones with significant values can be selected as valid diffractors.
[0031] FIG. 2 depicts a source (point S) pulling some streamers 15 (cables) with typically hundreds (even thousands) of receivers (point R) placed on them. As source radiates energy travels to diffractor point D and is scattered back. Scattered energy radiates backs and sweeps all of the receivers (points like R) on the streamers 15 .
[0032] Arrival time of diffracted energy is the sum of two terms: source term, T 1 , and receiver term T 2 , as shown in FIG. 2 . As source (x s ,y s ) and receiver (x r ,y r ) coordinates are known, the value of arrival time from an assumed diffractor location (x d ,y d ) can be calculated using a medium velocity, V, like 1500 m/s. The equation for this calculation is given in Eq. 2.
[0000]
T
=
T
1
+
T
2
=
1
V
(
(
x
s
-
x
d
)
2
+
(
y
s
-
y
d
)
2
+
z
d
2
+
(
x
r
-
x
d
)
2
+
(
y
r
-
y
d
)
2
+
z
d
2
)
EQ
.
2
[0033] Travel Time Equation for Source-Diffractor-Receiver Travel Path.
[0034] Here z d represents the relative (with respect to the source and receivers) depth of the diffractor which is assumed to be zero in general but one can scan for a range of depths as well, if desired.
[0035] Indeed, if stacking amplitude
[0000]
s
=
∑
n
=
1
N
a
n
EQ
.
3
[0036] Stack Amplitude as an Attribute.
[0000] rather than semblance values (defined in Eq. 1) are calculated, this invention will produce pre-stack migration, done for a small range of depths, and with velocity, V (medium velocity). Therefore, using such stack amplitudes for picking the location of diffractors in half space (x d ,y d ,z d ) is also a new approach.
[0037] To illustrate the method, note that arrival times form hyperbolic looking events 25 as depicted in FIG. 3 (for a small set of (five) cables). Each vertical line 20 in FIG. 3 depicts a trace (source-receiver pair) recorded by receiver on a cable during a particular 3-D shot. The wavelets on the traces depict the diffracted energy. The amplitude value, a n , (n=1, 2, . . . , N where N is the number of traces that diffractor contaminated) at the arrival time calculated by Eq. 2 for each source-receiver pair that can record energy from this diffractor with the recording time available on the seismic traces can be picked and put into semblance calculation given by Eq. 1.
[0038] When the travel time falls between the two time samples of the digitally recorded seismic trace then the value of sample, a n is interpolated from the nearby samples with known techniques of the prior art.
[0039] To increase the reliability (smoothness) of semblance values, as it is known in prior art, it is possible to use more than one time sample (centered at the arrival time) for a trace to improve the reliability of the semblance calculation. If M time samples, instead of a single one, are picked, then there is a matrix of numbers (A m,n ) to use in the semblance
[0000]
(
a
1
,
1
,
a
1
,
2
,
…
,
a
1
,
N
a
2
,
1
,
a
2
,
2
,
…
,
a
2
,
N
…
a
M
,
1
,
a
M
,
2
,
…
,
a
M
,
N
)
[0000] where rows, m=1, 2, . . . , M, represent time and columns, n=1, 2, . . . , N, represent space (traces).
[0040] Semblance calculations, as it is known in prior art, are made using Eq. 4:
[0000]
s
=
∑
m
=
1
M
(
∑
n
=
1
N
a
m
,
n
)
2
N
∑
m
=
1
M
∑
n
=
1
N
a
m
,
n
2
EQ
.
4
[0041] Semblance Calculation from M Samples Per Trace (Samples Centered at the Arrival Time).
[0042] The value of M can be arbitrary. However, practice shows that large values of M are not helpful. Lower values of M are preferable to increase both peak semblance values and resolution in time, which is equivalent in resolution in location (resolution in source to diffractor, diffractor to receiver distance means resolution in diffractor distance). A value of M about the size of the main peak of the diffracted arrival wavelet is best.
[0043] It is mentioned above that N in Eq. 1 is the number of traces that a diffractor has contaminated. There could be many such traces, coming from many sources and many streamers. There is not an increased benefit in using all these of contributions in one semblance calculation, as there are issues in mixing amplitudes from different shots and cables. For example, noise content differences would be one such obstacle. It was found that using only traces from one shot and one cable at a time tends to work the best. As there are many cables (c=1, 2, . . . , N c ) and many shots (p=1, 2, . . . , N p ), the results of multiple scans at one point (i,j) need to be accumulated
[0000]
s
(
i
,
j
)
=
∑
p
=
1
Np
∑
c
=
1
Nc
s
p
,
c
(
i
,
j
)
EQ
.
5
[0044] Semblance Accumulation from Many Cables and Shots.
[0045] One needs to keep track of the number of values summed for each position (i,j), known sometimes as “fold,” so that the results could be divided by its maximum to achieve physically meaningful semblance values (between 0 and 1). This is known as “normalization”. It is also possible to use the fold value at each location to do the normalization (i.e. division by Np*Nc), but that might enhance the value of a low fold semblance and hence cause an unreliable semblance value to be considered as a diffractor location. It was found that the maximum fold is a better value to use for the normalization.
[0046] For determination of the diffractor azimuth and individual scan values,
[0047] 1) For cables that are not far from the shot, as in current 3-D marine recordings, one cable alone cannot tell the azimuth of the diffractor. That is, a diffractor shows itself at two points that are symmetrically oriented with respect to the line formed by the cable, one being the correct image, the other one incorrect. Adding the results of the scans from multiple cables suppresses the incorrect image and enhances the correct one.
[0048] 2) When calculating individual scan values S pc (i,j), it saves computer time if one does not attempt to calculate this value for all grid points. That is, only those points that are within VT neighborhood of the receivers on the cable (see FIG. 4 ) need to be considered. If a′ and b′ are minimum and maximum found on the receiver x coordinates then considering diffractors with x coordinates that are in the range [a,b] where a=a′−VT and b=b′+VT is sufficient. Similarly, if c′ and d′ are minimum and maximum found on the receiver y coordinates, then considering diffractors with y coordinates that are in range [c,d] where c=c′−VT and d=d′+VT is sufficient. Here V represents medium velocity and T represents the recording time as before.
[0049] FIG. 5 shows the results of semblance scan obtained from 20 shots (N p =20) each pulling 8 cables (N c =8). Horizontal axis 30 is the x-coordinate and vertical axis 35 is the y-coordinate. The x-coordinate 30 increases towards the right, facing the figures and y-coordinate increases towards the top of the FIG. 5 . The scan increment used here is preferably 10 m in both x and y directions. Practice shows that scan increments as low as 5 m and as high as 100 m can be used. The finer the scan increment, more accurate the location of the local maxima. Sampling coarser than 100 m is not preferred and is not expected to yield accurate travel times for flattening the data for purpose of noise attenuation. The color code 40 is shown at the lower right corner of FIG. 5 . Semblance values vary between zero and one. Peak semblance value for this run was 0.239. Semblance values above 0.100 are clipped in the Figure.
[0050] FIG. 5 provides a visual display of the diffractor locations. It covers an area of roughly 40 km 2 . Actual locations are machine picked by requiring that a local maxima point needs to be the biggest amplitude in a space (x,y) window, typically and preferably specified as 100 m by 100 m. More explicitly, a user given window size in distance units (like meters) for local maxima determination is first converted to a window size in grid points, each side being an odd number (1, 3, 5, . . . ). If window size is 2m+1 by 2n+1 (where m and n are positive integers), then each point, (i,j) on the grid is checked to determine if it is the largest amplitude in 2m+1 and 2n+1 neighborhood:
[0000] a i,j ≧a i-u,j-v for −m≦u≦+m and −n≦v≦+n EQ.6
[0051] Local Maxima Checker Definition
[0000] where u and v are integers except u=v=o. All i and j locations, except the edges, i.e. all the points satisfying
[0000] m+ 1 ≦i≦i max −m and n+ 1 ≦j≦j max −n
[0000] are checked and (i,j) points satisfying Eq. 6 are taken as possible diffractor locations. Order in which one varies i and j depends on how the values are stored in the computer; preferably one first scans row indices on column 1 (i=1,i max ), then column 2 , then column 3 , etc.
[0052] FIG. 6 illustrates local maxima search window 50 for a 3-by-3 window for simplicity. For a center point 55 to be chosen as a local maxima, it must be greater than its eight neighbors 55 in FIG. 6 . For a 5-by-5 window the middle point must be greater than its 24 neighbors. For a (2m+1)-by-(2n+1) window the amplitude of the middle point must be greater than the amplitudes of its (2m+1)(2n+1)−1 neighbors.
[0053] Once a set of such diffractor locations are found, one can use methods known in prior art to flatten and reject diffracted energy for each location. Flattening is a process (depicted in FIG. 7 ) where diffracted event's travel times 60 are subtracted 65 from the trace. This is known in prior art as “static shift”. During this static shift, care must be taken not to lose data by extending (doubling) trace length and putting data at the bottom before static shifting upwards (otherwise data above diffraction will be lost).
[0054] There are numerous tools in geophysical industry to remove events contaminating the data. Among them are FK filter, regular and high-resolution radon filter, eigenimage filter, etc. Any of these could be used to suppress such diffracted energy. Flattening and flat event suppression is done for every diffractor found in the survey.
[0055] Because many varying and different embodiments may be made within the scope of the invention concept taught herein which may involve many modifications in the embodiments herein detailed in accordance with the descriptive requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.
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Coherency analysis, such as semblance scan or stacking amplitude, is used to locate diffractors. Once the diffractors are located, noise energy originating from the diffractors is minimized. Locations of each diffractor are determined by comparing the lateral coherency of the received amplitudes that each assumed diffractor position generates.
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[0001] This patent application is based on and claims the benefit of German Patent Application No. 10 2012 005 199.9 having a filing date of 16 Mar. 2012.
BACKGROUND OF THE INVENTION
[0002] 1. Technical Field
[0003] The invention relates to a method for drying laundry, wherein air for drying the laundry is heated by a burner and, at least during a part of the drying operation, at least a part of the air used to dry the laundry is fed back to the burner as recirculating air, if need be together with fresh air, and to a dryer for laundry, comprising a drum for receiving the laundry to be dried and comprising at least one burner for heating air which serves for the drying.
[0004] 2. Prior Art
[0005] Dryers for commercial laundries possess at least one burner, preferably a gas burner, for heating air which is used for drying. The air heated by the burner is passed through a preferably rotationally drivable drum containing the laundry to be dried. The air here absorbs moisture from the laundry to be dried. The moist air is afterwards led as waste air into the open and/or is fed back as recirculating air to the at least one burner and reheated by this.
[0006] At the beginning of the drying, the air leaving the drum contains the most humidity. This air cannot, or can only in small part, be reused as recirculating air. It must therefore, at least for the most part, be passed out of the dryer. At the beginning of the drying, only a small amount of recirculating air is therefore being carried. A large amount of fresh air is then fed, at least for the most part, via the burner to the dryer. As a result of this very large fresh air component, the at least one burner gets sufficient combustion air. At the conclusion of the drying operation, air having only a small amount of humidity leaves the drum. A relatively large amount of recirculating air and only a small amount of fresh air are then fed to the burner. The at least one burner then contains only very little fresh air or no fresh air at all, with the result that the burner works uneconomically. In many cases, an incomplete combustion with undesirable soot formation can ensue.
[0007] The object of the invention is to provide a method and a dryer for drying laundry, which can be operated with a relatively large recirculating air component, or with only recirculating air, economically and without negative impacts on combustion.
[0008] A method for the achievement of this object is a method for drying laundry, wherein air for drying the laundry is heated by a burner and, at least during a part of the drying operation, at least a part of the air used to dry the laundry is fed back to the burner as recirculating air, if need be together with fresh air, characterized in that the fresh air is transported to the burner at least during a part of the drying process. According to this, the fresh air is transported to the at least one burner at least during a part of the drying process. As a result of the active transport of fresh air to the burner, the fresh air is virtually blown or forced into the burner. A type of charging of the burner with fresh air occurs. As a result, the burner is also then supplied with sufficient fresh air if the recirculating air is returned in full or for the most part to the at least one burner without this adversely affecting the combustion. The drying can hence be realized with more recirculating air than previously. The inventive method thereby provides more economical drying.
[0009] Preferably, the fresh air is transported to the burner only in that phase of the drying in which a predominant part of the recirculating air is returned to the burner. This is founded on the recognition that, at the start of the drying operation, when, owing to the relatively high moisture content of the air used for drying, little recirculating air is employed, the at least one burner can itself draw in sufficient fresh air. As the recirculating air component increases, that is no longer the case, so that the fresh air is then actively transported to the respective burner and is thereby forced with pressure, so to speak, into the burner for the charging or boosting of this same. The fresh air thereby needs to be transported to the respective burner only in an end phase of the drying operation.
[0010] An advantageous refinement of the method provides for the fresh air to be fed under pressure, preferably through at least one fan or a blower, to the burner. This type of transport of the fresh air to the at least one burner represents the simplest and most effective charging of the burner. Through adjustment of the fan speed, the quantity of fresh air fed to the burner can be adjusted or controlled in accordance with requirements, so that the respective burner receives as much fresh air as it requires, based on the respective recirculating air component. The burner can thus receive that quantity of fresh air which is required for the, in each drying phase, optimal operation, wherein the quantity of fresh air can be increased the greater the recirculating air component becomes which is returned to at least one burner.
[0011] A further advantageous embodiment of the method provides for, where necessary, fresh air to also be fed behind the respective burner to the recirculating air warmed by this same. This happens before the warmed recirculating air has reached the laundry to be dried. In this way, only that quantity of fresh air which is necessary to the optimal operation of the burner needs to be fed to this same. Fresh air which is required over and above this can be fed directly to the warmed recirculating air. That too leads to more economical drying.
[0012] A dryer for the achievement of the object stated in the introduction is a dryer for laundry, comprising a drum for receiving the laundry to be dried and comprising at least one burner for heating air which serves for the drying, characterized in that an air flow generator for the transport of fresh air to the burner is assigned to the at least one burner. In this dryer, it is provided to assign to the at least one burner an air flow generator for the transport of fresh air to the burner. The at least one air flow generator ensures a virtually forced supplying of fresh air to the burner, in that the air flow generator virtually pumps and/or forces fresh air into the burner, to be precise particularly when, due to a relatively large recirculating air component, the burner can no longer automatically draw in the fresh air necessary for optimal combustion.
[0013] Advantageously, the air flow generator is assigned to a supply line for fresh air to the respective burner, or to a common supply line for all burners. The fresh air can be transported by the at least one air flow generator in the at least one supply line directly to the or each burner.
[0014] A further advantageous embodiment of the dryer provides that the at least one air flow generator is configured to generate a variable stream of fresh air to the burner. As a result, the fresh air can be adjusted or controlled in accordance with requirements. A sufficient quantity of fresh air for optimal operation, in particular for optimal combustion, is thereby fed to the respective burner.
[0015] In one advantageous embodiment of the dryer, the air flow generator is configured as at least one fan. If a plurality of burners are present, a dedicated fan is preferably assigned to each burner, though one fan can also be jointly assigned to all burners. As a result, each burner can be specifically and, if necessary, individually supplied with fresh air in sufficient quantity.
[0016] A preferred refinement of the invention provides, behind the at least one burner, a preferably variable and/or closable feed opening for fresh air which can be mixed to the air warmed by the burner.
[0017] It can preferably be provided that at least one fan or at least one blower for the generation of a recirculating air flow, and/or a closable or variable waste air outlet for at least a part of the recirculating air, are provided. The at least one fan can generate a specific recirculating air flow, in particular a recirculating air flow having a desired flow velocity and/or a desired recirculating air stream. The closable or variable waste air outlet serves to regulate the recirculating air component which is returned to the at least one burner and, having been warmed, is fed from this back to the laundry. That part of the moist air which is not used as recirculating air can be led off into the open for evacuation of the moisture which accrues when the laundry is dried in the dryer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] A preferred illustrative embodiment of the invention is explained in greater detail below with reference to the drawing, wherein:
[0019] FIG. 1 shows a schematic cross section through a dryer,
[0020] FIG. 2 shows a schematic cross section through the dryer according to FIG. 1 , with arrows for illustration of the air flows, and
[0021] FIG. 3 shows a schematic horizontal section III-III through an upper part of the dryer in the region of a burner.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0022] The dryer represented schematically in the figures serves for the highly effective and energy efficient drying of laundry. Such a dryer is used, above all, in commercial laundries. In the dryer which is shown here, air for drying of the laundry is heated by a single burner 10 . The dryer can also, however, have a plurality of burners 10 arranged in parallel or in series. The burner 10 can be constituted both by a gas burner and by an oil burner.
[0023] The dryer possesses an outer housing 11 , preferably a closed, box-like housing 11 , in which a drum 13 , which can be driven in rotary motion about a horizontal rotational axis 12 , the said burner 10 , a recirculating air fan 14 and, further below, the described air guide ducts are disposed.
[0024] The rotationally drivable drum 13 serves to receive the laundry to be dried. It possesses a loading and unloading opening (not shown). In particular the casing 15 of the cylindrical drum 13 is of air-permeable configuration to enable air used for the drying to flow through the drum 13 and the initially damp laundry present therein. The drum 13 is rotatably mounted in a lower compartment 16 of the housing 11 .
[0025] The drum 13 is partially surrounded at a short distance from the cylindrical casing 15 by air-impermeable, arc-shaped walls 17 and 18 . The walls 17 and 18 lie on a circular path running concentrically around the rotational axis 12 , whereby the air-impermeable walls 17 and 18 surround the cylindrical casing 15 of the drum 13 at a short distance apart for the formation of a narrow gap 19 between the casing 15 of the drum 13 and the walls 17 and 18 . Each of the preferably equal-sized walls 17 and 18 extends over about 120° to 150°, preferably about 135°, of the periphery of the drum 13 . In this way, between transverse rims, running parallel to the rotational axis 12 , of different walls 17 and 18 are formed openings which are left free by these same and are diametrically opposing, to be precise an upper air inlet opening 20 and a lower air outlet opening 21 . Mutually facing, spaced-apart transverse rims of the walls 17 and 18 are sealed in the region of the air inlet opening 20 , with respect to a horizontal partition 23 demarcating the lower compartment 16 from an above-situated upper compartment 22 , by transverse walls 24 and 25 . In addition, a lower transverse rim of the (in FIG. 1 ) right-hand wall 17 is separated by a horizontal wall 26 to the nearest (left-hand) external wall 27 of the housing 11 .
[0026] In the upper compartment 22 of the housing 11 is located, at a distance from the external wall 27 , the recirculating air fan 14 , though this can also be in the form of a different air flow generator, for example a blower. In addition to the recirculating air fan 14 , there is also arranged in the upper compartment 22 , roughly in the middle, the burner 10 , to be precise such that a schematically indicated elongate flame tube 28 for generating a plurality of adjacent flames runs parallel to the rotational axis 12 . The axes of the flames run horizontally, to be precise transversely to the rotational axis 12 . Alternatively, the burner 10 can also be configured such that it generates just a single horizontal flame, extending transversely to the rotational axis 12 .
[0027] In the shown illustrative embodiment, the burner 10 is housed in the upper compartment 22 . For this purpose, a rear wall 29 is assigned to the burner 10 on the rear side. Above and beneath the burner 10 are located parallel, horizontal air guide walls 30 , 31 , which are both connected to the rear wall 29 . Parallel, free edges 32 of the air guide walls 30 and 31 form a preferably elongate, vertical air outlet opening 33 of the housing surrounding the burner 10 and made up of the rear wall 29 and the air guide walls 30 and 31 . The substantially fully open air outlet opening 33 thus forms a wide-slot opening or wide-slot nozzle. The air outlet opening 33 is distanced from an external wall 34 of the housing 11 , which external wall lies opposite the external wall 27 of the housing 11 . Similarly, the upper air guide wall 30 is distanced from an upper top wall 35 of the housing 11 of the dryer. Consequently, the rear wall 29 , which extends only up to the upper air guide wall 30 , ends also at a distance below the top wall 35 of the housing 11 .
[0028] In a bevelled upper, right-hand corner region between the horizontal top wall 35 and the vertical (right-hand) external wall 34 is located an air vent 36 . Below the air vent 36 is provided, inside the upper compartment 22 , a recirculating air flap 37 . The recirculating air flap 37 is pivotable about a horizontal pivot axis 38 , preferably by a drive (not shown). The recirculating air flap 37 is pivotable to the point where it, on the one hand, in an open setting completely closes off the air vent 36 and, on the other hand, in a closed setting extends the free edge 32 of the air guide wall 30 above the burner 10 to the external wall 34 and thereby forms a seal. Between the said extreme settings, optional intermediate settings of the recirculating air flap 37 are possible.
[0029] By virtue of the above-described configuration of the housing 11 , in particular of the lower compartment 16 and of the upper compartment 22 , a specific air flow can be induced in the dryer. Thus, the air outlet opening 21 opens out into a backflow chamber 39 closed off by the wall 18 , the transverse wall 25 , the wall 26 and the external wall 27 . By an opening (not shown in the figures) in the partition 23 , the backflow chamber 39 in the lower compartment 16 is connected to a backflow chamber 40 in the upper compartment 22 . This backflow chamber 40 is bounded by the partition 23 , the top wall 35 , an upper part of the external wall 27 , the rear wall 29 behind the burner 10 and the air guide wall 30 , distanced from the top wall 35 , above the burner 10 .
[0030] Between the upper part of the external wall 34 and the air outlet opening 33 situated at a distance therefrom, the chamber, surrounding the burner 10 , between the air guide walls 30 and 31 , the transverse walls 24 , 25 and the air inlet opening 20 into the drum 13 is formed an inflow chamber 41 . Via the inflow chamber 41 , the upper compartment 22 and the lower compartment 16 are also connected to each other by an appropriate opening in the partition 23 . When the recirculating air flap 37 is closed, the backflow chamber 40 and the inflow chamber 41 can be separated from each other. By the middle setting (shown in FIG. 1 ) of the recirculating air flap 37 , a partial connection of the backflow chamber 40 to the inflow chamber 41 and a partial opening-up of the air vent 36 is adjustable.
[0031] According to the invention, an air flow generator is assigned to the burner 10 . This is represented symbolically in FIG. 3 . This particular illustrative embodiment relates to an air flow generator configured as a fan 42 . The air flow generator can also be formed by a plurality of fans 42 . Through an intake opening (not shown), the fan 42 draws in fresh air from outside the housing 11 of the dryer and transports this to the burner 10 , preferably into the burner 10 . As a result of the lateral arrangement of the fan 42 next to the housing 11 , supply air or fresh air is transported or blown by the fan into the housing 11 in a direction parallel to the rotational axis of the drum 13 . The fresh air transported by the fan 42 into the housing makes its way inside the burner 10 , for which purpose it flows through the housing surrounding the burner 10 . If need be, it can be provided to transport the fresh air through the elongate flame tube 28 , to be precise preferably together with the gas to be combusted by the burner 10 . It is also conceivable, however, to feed the supply air or fresh air transported by the fan 42 to the inside of the burner 10 past the outside of the flame tube 28 or around the burner 10 .
[0032] The fan 42 can be driven by, for example, an electric motor 43 . Preferably, the speed of the electric motor 43 is variable or controllable or can be regulated. The throughput of fresh air or supply air through the fan 42 can thereby be altered and thus adapted to requirements. A desired stream of fresh air can thereby be transported to the burner 10 .
[0033] Opening out into the inflow chamber 41 , behind the air outlet opening 33 between the air guide walls 30 and 31 , viewed in the direction of flow, is a fresh air socket (not represented in the figures) disposed on a wall of the housing 11 . The opening of the fresh air socket is preferably variable in cross section. It is also conceivable for the fresh air socket to be able to be totally shut off. Via the fresh air socket, additional fresh air can be fed to the inflow chamber 41 (in the direction of flow) behind the burner 10 and/or outside this same. The quantity of fresh air is variable by altering the cross section of the fresh air socket. The fresh air supply via the fresh air socket can also be totally cut off.
[0034] The inventive method is explained in greater detail below with reference to the previously described dryer with reference to, in particular, FIG. 2 :
[0035] The drying operation commences with the supply of air 44 heated by the burner 10 through the inflow chamber 41 and the air inlet opening 20 to the rotationally driven drum 13 in which the laundry to be dried is found. As the air 44 flows along the laundry, which initially is still very damp, the air absorbs a large amount of moisture. As a result, relatively moist air 45 leaves the drum 13 through the air outlet opening 21 . The moist air 45 flows through the backflow chamber 39 in the lower part 16 into the backflow chamber 40 in the upper compartment 22 , where it is transported onward by the recirculating air fan 14 .
[0036] The moist air 45 containing, at the start of the drying operation, a high moisture component is initially, with the recirculating air flap 37 completely or almost completely closed, evacuated fully or for the most part through the air vent 36 from the housing 11 of the dryer, as waste air 46 . As replacement for the evacuated waste air 46 , fresh air is fed to the dryer from outside. This happens mainly through the burner 11 , where the fresh air fed from outside serves as combustion air. This fresh air is initially drawn in automatically by the burner 10 . For the support of the air supply to the burner 10 , it can also already be provided in this drying stage, however, for fresh air to be transported to the burner 10 through the fan 42 . Additionally or alternatively, further fresh air can, where necessary, be fed behind the burner 10 directly to the inflow chamber 41 .
[0037] As the drying process progresses, the moisture content in the moist air 45 declines. Then a part of the moist air 45 is fed as recirculating air past the burner 10 and/or through the burner 10 to the drum 13 containing the laundry to be dried. For this purpose, the recirculating air flap 37 is partially opened by being pivoted in the clockwise direction (related to the representation in FIG. 2 ) about the pivot axis 38 . The recirculating air flap 37 is opened sufficiently wide for the desired recirculating air stream to set in, i.e. a specific moist air component 45 is again fed as recirculating air 47 to the drum 13 and a remaining moist air component 45 is passed through the air vent 36 as waste air 46 into the open. That part of the moist air 45 which is passed through the air vent 36 as waste air 46 into the open is replaced by fresh air, which the fan 42 transports to the burner 10 or which can still be drawn in automatically by the burner 10 . This fresh air is passed through the burner 10 and here serves as combustion air. The air leaves the burner 10 as heated air 44 , which in the inflow chamber 41 mixes with the recirculating air 47 and, together with this same, is re-fed as heated air 44 to the drum 13 .
[0038] In dryers, in particular of the kind for commercial laundries, recirculating air 47 is employed in order to reuse the thermal energy in the moist air 45 and avoid having to reheat so much cold fresh air. The recirculating air component 47 is therefore gradually increased with increasing drying time. To this end, the recirculating air flap 37 is gradually opened further, so that it increasingly closes the air vent 36 and little moist air 45 having still considerable residual heat escapes through the air vent 36 into the open.
[0039] As the component of moist air 45 which has been reused and returned to the burner 10 , i.e. recirculating air 47 , increases, the burner 10 is itself able to draw in only little fresh air from outside. Sufficient fresh air is then no longer available to the burner 10 . This gives rise to an unfavorable or incomplete combustion, which, inter alia, can lead to harmful soot formation. It is therefore provided according to the invention to transport fresh air through the fan 42 to the burner 10 as the recirculating air component 47 increases. The burner 10 is then boosted or charged virtually with fresh air, which is forced or pumped through the fan 42 to the burner 10 . The burner 10 thereby receives sufficient fresh air for optimal combustion, whereby, in the end phase of the drying, drying can be realized with more recirculating air than has hitherto been normal, or with recirculating air only.
[0040] If, due to the fresh air transported by the fan 42 to the burner 10 , only recirculating air 47 is employed at the end of the drying operation, so that the whole of the moist air 45 is then reused as recirculating air 47 , then the recirculating air flap 37 lies fully open, in that, as a result of having been pivoted up to the air vent 36 , it closes this off, so that no moist air 45 can any longer flow as waste air 46 through the air vent 36 into the open and the whole of the moist air 45 can be fed back to the burner 10 as recirculating air. The burner reheats the recirculating air, so that the thereby heated recirculating air is fed back to the drum 13 containing the almost dry laundry.
[0041] The moist air 45 used as recirculating air 47 can be passed, wholly or partially with the fresh air transported by the fan 45 to the burner 10 , through the burner 10 . If the moist air 45 used as recirculating air is led only partially through the burner 10 , a part of the moist air 45 is led past the burner 10 , likewise as recirculating air, to join before the air outlet opening 33 with the air 44 heated by the burner 10 and/or warmed recirculating air, so that the recirculating air 47 , and the air 44 warmed by the burner 10 and likewise formed from recirculating air 47 , can be fed in its entirety through the inflow chamber 41 back to the drum 13 containing the laundry.
[0042] If the dryer is operated completely or for the most part with recirculating air 47 , behind the air outlet opening 33 a bit more fresh air can, where necessary, be fed from outside directly to the inflow chamber 41 . This is generally unnecessary, however, in the case of complete or almost complete recirculating air operation.
[0043] The fresh air transported by the fan 42 to the burner 10 and through this same is variable in quantity by appropriate controlling of the speed of the fan 42 . It is thereby possible to alter both the stream of fresh air to and through the burner 10 and the pressure of the fresh air. The burner 10 can thereby be charged or boosted more or less strongly according to the recirculating air component 47 .
[0044] At the start of the drying operation, when little circulating 47 is employed, the fan 42 , if need be, can be totally switched off, so that the burner 10 then automatically draws in the necessary fresh air. Only once the recirculating air component increases, in particular predominates, or only recirculating air 47 is used, is the fan 42 started up, so that fresh air, preferably under pressure, is then transported to the burner 10 or blown into the burner 10 , the pressure and/or the quantity of fresh air which is transported by the fan 42 to the burner 10 rising continuously with the increase in the recirculating air component 47 . Where the dryer is operated only with recirculating air 47 , the stream of fresh air and/or the pressure of the fresh air, by appropriate operation of the fan 42 , reach a maximum.
REFERENCE SYMBOL LIST
[0000]
10 burner
11 housing
12 rotational axis
13 drum
14 recirculating air fan
15 casing
16 lower compartment
17 wall
18 wall
19 gap
20 air inlet opening
21 air outlet opening
22 upper compartment
23 partition
24 transverse wall
25 transverse wall
26 wall
27 external wall
28 flame tube
29 rear wall
30 air guide wall
31 air guide wall
32 edge
33 air outlet opening
34 external wall
35 top wall
36 air vent
37 recirculating air flap
38 pivot axis
39 backflow chamber
40 backflow chamber
41 inflow chamber
42 fan
43 electric motor
44 air
45 moist air
46 waste air
47 recirculating air
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A method for providing fresh air fed through a fan to a burner of a dryer, thereby charging the burner, when the dryer is operated with recirculating air. In commercial dryers in which the drying air is heated by a burner, it is customary to reuse the moist air leaving a drum containing the laundry to be dried as recirculating air. The recirculating air component is increased with increasing drying of the laundry. At the end of the drying operation, when the moist air no longer contains as much moisture as at the start, the moist air is used as recirculating air. The burner then no longer gets enough combustion air, which leads to an incomplete combustion. The dryer can be operated with a higher recirculating air component, an optimal combustion being guaranteed through the charging of the burner with fresh air. The invention permits more economical drying.
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FIELD OF THE INVENTION
The present invention relates to computer systems, and more specifically, to power management in a computer system.
BACKGROUND OF THE INVENTION
Many of today's computer systems are mobile. In mobile computer systems, the control of the computer system may be split up between a main processor and a mobile system controller. The mobile system controller may control a dynamic memory and a cache.
Such mobile computer systems are generally powered by batteries at least some of the time. Users expect to use their mobile computer for a long time without recharging the batteries. Today's mobile computer systems extend battery life by creating more powerful batteries and/or by decreasing power consumption of the mobile computer system. One method of decreasing the power consumption of the computer system is to have a sleep mode.
The sleep mode involves turning off the power to at least some of the components of the computer system, thereby decreasing power consumption and increasing battery life. However, dynamic memory in the computer system has to be maintained even when the computer system is in sleep mode. The memory used in the computer system may be synchronous dynamic random access memory (SDRAM), extended data out random access memory (EDO DRAM), fast page mode (FPM) DRAM, or another type of dynamic random access memory (DRAM). All of these types of DRAM need be periodically refreshed in order to maintain the data values stored in them. In non-self-refresh type of DRAM, the system clock has to provide refresh signals to the DRAM. However, the system clock consumes power.
Some types of DRAM, including SDRAM, are able to execute self-refresh cycles. In the self-refresh cycle, the DRAM uses an internal clocking to refresh itself, and no external clocks are required. In these types of DRAM, power consumption is reduced by shutting off the system clock. Once the DRAM is placed into the self-refresh mode using a self-refresh command, the system clock may be turned off.
However, the memory controller needs to remain powered, to maintain the DRAM in the self-refresh mode and in order to exit from the self-refresh mode. Furthermore, if EDO DRAM is also included in the system, the system clock is needed to time refresh cycles for the EDO DRAM. The memory controller consumes power, as does the system clock. Because extending battery life is a goal, a system that permits reduction of the power consumed by the computer system during sleep mode is advantageous.
SUMMARY OF THE INVENTION
The present invention is a memory control system. The memory control system includes a first memory controller designed to access and refresh a DRAM using a clock, during a first operation mode. The memory control system further includes a suspend memory controller designed to maintain the DRAM during a second operation mode and to exit from the second operation mode. During the second operation mode the clock or both the clock and power are turned off to the first memory controller. Upon returning to the first operation mode from the second operation mode, the first memory controller does not need to be initialized again. Since a significant proportion of the power is consumed by the first memory controller, power consumption is reduced during the second operation mode using this system.
The present memory control system may support synchronous dynamic random access memory (SDRAM).
The present memory control system may also support both types of memory, SDRAM and EDO DRAM.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
FIG. 1 is a block diagram of one embodiment of the computer system of the present invention.
FIG. 2 is a block diagram of one embodiment of the memory control system of to the present invention.
FIG. 3 is a block diagram of one embodiment the suspend memory controller of the present system.
FIG. 4 is an overview timing wave form diagram of entry into and exit from sleep mode.
FIG. 5 is a state diagram of the memory controller.
FIG. 6 is a timing wave form diagram of entry into the sleep mode for memory banks including SDRAM banks.
FIG. 7 is a timing wave form diagram of exit from the sleep mode for memory banks including SDRAM banks.
FIG. 8 is a flowchart of the refresh cycles for a memory system including EDO DRAM according to one embodiment of the present invention.
FIG. 9 is a timing wave form diagram of the sleep mode with memory banks including EDO DRAM and FPM DRAM banks.
DETAILED DESCRIPTION
A method and apparatus for a memory control system is described. In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the present invention.
Overview
FIG. 1 illustrates a block diagram of computer system in which the present invention may be implemented. Computer system 100 comprises a bus 101 or other communication means for communicating information, and a processor 102 coupled to bus 101 for processing information. Computer system 100 also comprises a read only memory (ROM) and/or other static storage device 106 coupled to bus 101 for storing information and instructions for processor 102 .
The computer system 100 further comprises a main memory 125 , a dynamic storage device for storing information and instructions to be executed. Main memory 125 also may be used for storing temporary variables or other intermediate information during execution of instructions. In one embodiment the main memory 125 is dynamic random access memory (DRAM). The computer system 100 also comprises a cache 115 for holding recently accessed data, designed to speed up subsequent access to the same data.
Computer system 100 further comprises a mobile system controller 120 coupled to the bus 101 to control access to the main memory 125 and cache 115 . In one embodiment, the mobile system controller 120 includes a cache controller, a memory controller, and a bus controller. The mobile system controller 120 is coupled to a peripheral component interconnect (PCI) bus 130 . Also coupled to the PCI bus 130 are PCI components, which are well known in the art and have not been shown to avoid obscuring the present invention.
Computer system 100 also includes a PCI input/output (I/O) controller 135 for controlling the I/O access to the mass storage device 107 . A mass storage device 107 such as a magnetic disk or optical disk and its corresponding disk drive can be coupled to the PCI I/O controller 135 . The PCI I/O controller 135 may also be coupled to an extended I/O bus 145 for connecting input and output devices to the computer system 100 . In one embodiment, the processor 102 , mobile system controller 120 , and PCI I/O controller 135 are separate components in the computer system 100 . Alternatively, functions of these components may be combined into one or more chips.
Computer system 100 can also be coupled via I/O bus 145 to a display device 121 , such as a cathode ray tube (CRT) or liquid crystal display (LCD), for displaying information. An alphanumeric input device 122 is typically coupled to I/O bus 145 for communicating information and command selections to processor 102 . Another type of user input device is cursor control device 123 , such as a mouse, a trackball, trackpad, or cursor direction keys for communicating direction information and command selections to processor 102 and for controlling cursor movement on display device 121 . Alternatively, other input devices such as a stylus or pen can be used to interact with the display. The computer system 100 can also be coupled via I/O bus 145 to a hard copy device 124 such as a printer. The computer system 100 may further be coupled via the I/O bus 145 to a communication device 127 . The communication device 127 may be a speaker or microphone, or other device to communicate between a user and a computer system 100 . Alternatively, these devices may be coupled to the computer system 100 via the PCI bus 130 , or bus 101 .
The present invention is related to power management in a computer system 100 . According to one embodiment, power management is performed by computer system 100 in response to the processor 102 , the mobile system controller 120 and/or the PCI I/O controller 135 executing sequences of instructions contained in main memory 125 . Execution of the sequences of instructions causes the computer system 100 to enter into a sleep mode, as will be described hereafter. In alternative embodiments, circuit logic internal to the computer system 100 may be used in place of, or in combination, with software to implement the present invention. Thus, the present invention is not limited to any specific hardware and software, or combination of the two.
A memory control system including a first memory controller is described. The memory control system is designed to enter the first memory controller into sleep mode, turning power off to the first memory controller. The contents of the DRAM are maintained even when clocks and/or power to the majority of the system is shut off. The present memory control system may be used with various memory types, and combinations of memory types, including synchronous DRAM, extended data out DRAM(EDO DRAM), fast page mode DRAM (FPM DRAM), and others.
FIG. 2 is a block diagram of one embodiment of the memory management system of the computer system of present invention. Memory system controller 200 accesses and controls memory in the computer system. Memory system controller 200 has two input clocks HCLK 205 and PCLK 215 . The HCLK 205 is the host bus clock and is used by processor and memory system controller 120 . The PCLK 215 is the PCI clock shared by memory system controller 120 and PCI devices. In one embodiment, HCLK 205 is a 66 MHz clock and PCLK 215 is a 33 MHz clock.
The majority of the logic within the memory system controller 200 is connected to main power, MAINPWR 290 , which is the primary power connection, supplying power to most of the computer system. In one embodiment MAINPWR 290 is coupled to the PCI I/O controller 135 . Some of the logic within the memory system controller 200 connected to SUSPWR 295 . The logic that is connected to MAINPWR 290 is referred to as normal logic, the logic that is connected to the SUSPWR 295 is the suspend well. The portion of the memory system controller 200 which is normal logic is the first memory controller 210 . The portion of the memory system controller 200 which is within the suspend well is the second memory controller 220 , or suspend memory controller 220 .
One embodiment of the computer system of the present invention has two sleep modes. The first sleep mode is referred to herein as the Stop Clock sleep mode (SC mode), during which clocks HCLK and PCLK are turned off. The second sleep mode is referred to herein as the Suspend-to-RAM sleep mode (STR mode), during which both the clocks and the MAINPWR 290 are turned off. During the STR mode, the suspend well containing the suspend memory controller 220 is powered by SUSPWR 295 .
Because the suspend well remains powered even in sleep mode, the size of the suspend well is reduced in order to reduce the power consumption of the circuit during the sleep mode, and thereby extend the battery life. During normal operation, the suspend memory controller 220 acts as part of the memory system controller 200 . However, during sleep mode, the first memory controller 210 is disconnected from the clock and/or power, and the suspend memory controller 220 acts as the memory controller. The suspend memory controller 220 refreshes the memory in the sleep mode and exits the first memory controller 210 from sleep mode at the appropriate time.
The SDRAM 225 is accessed and refreshed synchronously, using the HCLK signal 205 in the fully powered mode, referred to herein as normal operation mode. The commands to the SDRAM, during normal operation mode, are sampled by strobing the CS 265 , SRAS 285 , SCAS 280 , WE# 270 , and CKE 260 signals at the positive edge of HCLK signal 205 . The function of these signals is described in more detail, for example, in the data sheet for the IBM0364404C 64Mb Synchronous DRAM manufactured by IBM Corporation of Armonk, New York. Additionally, these and other signals are described in more detail below. The EDO DRAM 230 is refreshed by a CAS before RAS refresh. In one embodiment, the EDO DRAM 230 may have a self-refresh mode.
FIG. 3 is a block diagram of one embodiment of the suspend memory controller 220 of the present system. The suspend memory controller 220 has as an input the SUS_STAT# signal 299 , which goes low in order to indicate entry into the sleep mode. Depending on the type of sleep mode, the STR or SC mode, either clocks are turned off or both clocks and main power are turned off to normal logic. The entry and exit from the sleep modes is described in more detail below.
The SDSLEEP 245 is an input to the suspend memory controller 220 from the normal logic. The PCLK signal 215 is also input to the suspend memory controller 220 . The PCLK signal 215 and SDSLEEP signal 245 are input to a first state machine 310 . The output of first state machine 310 is the SCKE signal 315 . The SCKE signal 315 is an input to an AND logic circuit 320 . The SDCKE signal 240 , generated by the first memory controller 210 , is the second input to the AND logic circuit 320 .
The output of the AND logic circuit 320 is a CKE signal 330 , a clock enable signal. The CKE signal 330 is an input to the SDRAM 225 (not shown) and is used, along with other signals, to place the SDRAM into a self-refresh mode. When CKE signal 330 goes low, the SDRAM determines whether the CS# signal 265 is low and WE# signal 270 is high in the same clock cycle. If the CKE signal 330 and CS# signal 265 low and the WE# signal 270 high, the SDRAM enters into a self-refresh mode. The self-refresh mode is maintained by holding CKE low. The exit from self-refresh mode takes place when the CKE signal goes high.
Because the CKE signal is the output of an AND logic 320 , if either SCKE or SDCKE signal is low, the CKE signal is low. Therefore, the status of the SDCKE signal 240 is irrelevant if the SCKE signal 315 is maintained low. The state machine 310 is responsible for maintaining the value of the SCKE signal during the sleep mode, when SDCKE 240 is high.
The bank population indication (BPOP) signal 235 is also input to the suspend memory controller 220 . In one embodiment, the BPOP signal 235 indicates which memory banks are populated by EDO or FPM DRAM. When the SDRAM banks are in self-refresh mode, they need not be refreshed, therefore the BPOP signal 235 need not indicate the presence of SDRAM banks. The EDO or FPM DRAM can be either a self-refresh type EDO or non-self-refresh type EDO or FPM DRAM. In that case, the BPOP signal 235 may further indicate the type of EDO or FPM DRAM is present.
An internal ring oscillator, DOSC 340 , is further included in the suspend memory controller 220 . If there is DRAM which requires refreshing, such as EDO or FPM DRAM, the DOSC 340 is used to generate the refresh cycles. This allows the turning off of the PCLK signal 215 . In one embodiment, the DOSC generates refresh cycles using the RAS, CAS, and WE# signals. In one embodiment, the DOSC 340 is disabled if the BPOP signal 235 indicates that there is only SDRAM in the system, and therefore the refresh cycles are not needed.
A second state machine 350 is used to generate signals for refreshing EDO or FPM DRAM. The second state machine 350 uses the BPOP signal 235 to generate a SUSRAS signal 360 . The SUSRAS signal 360 is an input to a multiplexer (MUX) 370 . The MUX 370 also has the normal RAS, (NRAS) 250 , as an input. The NRAS signal 250 is generated by the first memory controller 210 . The select signal 350 determines whether to select the SUSRAS 360 or NRAS signal 250 . The select signal 350 is an output of the first state machine 310 . The select signal 350 indicates whether the computer system is in normal operation mode or sleep mode. The output of the MUX 370 is the RAS signal 380 that is an output signal of the suspend memory controller 220 . A CAS signal and WE signal are similarly generated.
In one embodiment, if a computer system only includes SDRAM 225 , or other types of DRAM which have a self-refresh mode, the DOSC 340 and second state machine 350 may be eliminated.
FIG. 4 is an overview timing wave form diagram of entry into and exit from sleep mode according to the present invention. The horizontal axis represents time units. The HCLK signal 205 is the clock which is used by the first memory controller 210 . The PCLK signal 215 , while it is on, is the clock used by the suspend memory controller 220 .
The SUS_STAT# signal 299 initiates entry into the sleep mode. In one embodiment, the SUS_STAT# signal 299 is an active low signal. In one embodiment, the SUS_STAT# signal 299 is controlled by an external pin of the mobile system controller 120 . In one embodiment, the external pin is asserted and deasserted by the PCI I/O controller 135 .
A period of t ref elapses between the assertion of the SUS_STAT# signal 299 and the turning off of the clock signals PCLK 215 and HCLK 205 . The period t ref is long enough to complete all pending refresh requests of all memory banks, complete entry into the sleep mode, and transfer control to the suspend memory controller 220 . In one embodiment, the period t ref is 32 μs. The period during which the clocks/power is off can range from a few microseconds to hours. During Suspend-to-RAM (STR), MAINPWR 290 is turned off in addition to clock signals PCLK 215 and HCLK 205 . In one embodiment, MAINPWR 290 is turned off slightly later than the PCLK signal 215 and HCLK signal 205 . In another embodiment, MAINPWR 290 is turned off at the same time as the PCLK 215 and HCLK signal 205 .
If the sleep mode is Suspend-to-RAM, and the MAINPWR 290 is turned off, the exit from the sleep mode is as follows. First, the MAINPWR 290 and the PCLK 215 and HCLK 205 are turned on. This restores power to the normal logic. Then, the PCIRST# signal 430 and CPURST# signal 460 are asserted. In one embodiment, the PCI reset signal, PCIRST# 430 , is an external pin indicator which initiates the reset of the normal logic 200 . In one embodiment, the PCIRST# signal 430 is triggered by the PCI I/O controller 135 . In one embodiment, because power is turned off to most of the computer system, a CPU reset signal, CPURST# 460 , is used to reset logic in the processor.
The CPURST# signal 460 and PCIRST# signal 430 are used to reset the registers. Because the registers in the normal logic 200 are not maintained during the power management mode, they may contain invalid values on power up. The PCIRST# signal 430 initiates this process for the PCI components, while the CPURST# signal 460 initiates this process for the CPU.
The PCIRST# 430 and CPURST# signals 460 are deasserted once the reset process is complete.
A period t d before PCIRST# 430 is deasserted, SUS_STAT# 299 is deasserted. The period t d allows the first state machine 310 to determine whether the exit is with or without PCIRST# 430 . This determines whether the exit is from a Stop Clock or from a Suspend-to-RAM type of sleep mode.
As described below, the exit from Stop Clock, which does not require the PCIRST# signal 430 , is different from exit from Suspend-to-RAM.
The CPURST# signal 460 is deasserted t c after the assertion of the PCIRST# signal 430 . In one embodiment, both t d and t c are 32 μs. In one embodiment, while the PCIRST# signal 430 and CPURST# signal 460 are asserted, the processor 101 executes instructions to restore the contents of the registers to the state they were before to power-off. After register values are restored, NREF_EN register 440 is written to. In one embodiment, the NREF_EN register 440 is an internal register of the memory system controller 200 . In one embodiment, the NREF_EN register 440 is updated by the processor 101 . The NREF_EN register 440 is asserted to indicate that the registers have been restored to their pre-sleep mode state. The suspend memory controller 220 then transfers control back to the first memory controller 210 . In one embodiment, the CKE signal 260 is deasserted at approximately the same time as the transfer of control.
If the sleep mode is a Stop Clock mode, the exit from the sleep mode is as follows. First, the clock signals PCLK 215 and HCLK 205 are turned back on. Because power was not removed from the normal logic, neither the PCIRST# 430 nor the CPURST# 460 signals are asserted. Additionally, since power was on, the register values need not be restored, and therefore the NREF_EN register 440 is not written to. Therefore, the SUS_STAT# signal 299 is asserted to initiate exit from the sleep mode. During the period t d , the first state machine 310 determines that the PCIRST# signal 430 is not asserted.
Therefore, a period of time after the deassertion of the SUS_STAT# signal 299 , control is transferred to the first memory controller 210 and the CKE signal 260 is deasserted.
SDRAM Application
The present system is used for memories including a synchronous dynamic random access memories (SDRAM).
FIG. 5 illustrates a simplified state diagram for a first memory controller 210 according to the present invention. Upon power on, the first memory controller 210 is in the idle state 510 . From the idle state 510 , the first memory controller 210 moves to the initialization state 520 if the idle state 510 occurred the first time power is applied to the SDRAM. In the initialization state 520 , the SDRAM is initialized according to its specification. Initialization destroys any information stored in the SDRAM.
From the initialization state 520 , the first memory controller 210 moves to the normal operation state 530 . In the normal operation state 530 , the first memory controller 210 accesses the memory and refreshes the memory. In one embodiment, the SDRAM is refreshed in the normal operation state 530 using CAS-before-RAS (CBR) refresh operations.
Transition to the sleep state 540 may be triggered by an indicator signal, SUS_STAT# 299 , being asserted (i.e., going low). When the SUS_STAT# signal 299 is asserted, the first memory controller 210 moves to a sleep state 540 .
Once SUS_STAT# signal 299 is asserted, the first memory controller 210 moves into the sleep state 540 . In the sleep state 540 , the first memory controller 210 completes the pending refresh cycles for the DRAM banks. Then the SDRAM banks are placed into the self-refresh mode. The control for maintaining the SDRAM memory in self-refresh mode is transferred over to the suspend memory controller 220 . The details of this operation are explained below using a timing diagram.
When the IN_SUS signal 255 goes low, indicating the completion of the transfer of control to the suspend memory controller 220 , the first memory controller 210 moves back to the idle state 510 . The clock to the first memory controller 210 is turned off. Additionally, the power to the first memory controller 210 may be turned off. The timing of these actions is shown in more detail in FIG. 6 below.
Upon waking up from the idle state 510 , the system moves directly to the normal operation state 530 if the previous state was a sleep state 540 . If the power to the first memory controller 210 was removed during the sleep mode, after reset the state machine will be in an idle state 510 . After waking up, during the transition from the idle state 510 to the normal state 530 , the initialization state 520 is avoided. This maintains the data in the memory.
FIG. 6 is a timing wave form diagram of the sleep mode with memory banks including SDRAM banks. FIG. 6 represents the period of initial entry into the sleep mode, labeled t ref in FIG. 4 . The HCLK signal 205 is the clock used by the normal logic 200 and the first memory controller 210 . The PCLK signal 610 is used by the PCI components and the suspend memory controller 220 .
The SUS_STAT# signal 299 initiates the sleep mode, as described above with respect to FIG. 5 . Once the SUS_STAT# signal 299 is asserted, all pending memory refresh cycles are completed (not shown in Figure). The SDRAM banks are then placed in a self-refresh mode. To accomplish this a self-refresh command is generated by the first memory controller. In one embodiment, the self-refresh command is when CKE 330 , CS# 265 , SRAS 280 , and SCAS 285 signals are asserted, and WE# 270 is maintained high. In one embodiment, all of these signals are asserted, and WE# 270 is deasserted on the same clock edge of the HCLK signal 205 . When the SDCKE signal 240 is low, the CKE signal 330 is also low, placing the SDRAMs in the self-refresh mode.
After the SDRAMs are in a self-refresh mode, the SDSLEEP signal 245 is asserted. The SDSLEEP signal 245 indicates to suspend memory controller 220 that the SDRAMs are in self-refresh mode. The suspend memory controller 220 then asserts SCKE signal 390 and generates the IN_SUS signal 255 . The IN_SUS signal 255 indicates to the first memory controller 210 that control of the memory has been transferred to the suspend memory controller 220 . The first memory controller 210 then moves to the idle state. The SDCKE signal 240 , maintained by the first memory controller 210 , is deasserted. However, the SCKE signal 390 of the suspend memory controller 220 maintains the CKE signal 330 low.
At this point, the SDRAMs are in a self-refresh mode, and the CKE signal 330 is maintained by the suspend memory controller 220 . The clocks, HCLK 205 and PCLK 610 , are turned off, and power may be removed from the first memory controller 210 . The process of exiting from the sleep mode is described with respect to FIG. 7 .
FIG. 7 illustrates a timing wave form diagram for exit from the Suspend-to-RAM sleep mode in which power to the first memory controller 210 is turned off.
The PCLK 215 and HCLK 205 are initially off. During the sleep mode the PCLK 215 is turned off, since it is not needed to refresh the memory or by the suspend memory controller 220 . The MAINPWR signal 290 , which provides power to the first memory controller 210 and other parts of the computer system 100 , is off as well. The PCLK signal 215 , HCLK signal 205 , and MAINPWR signal 290 are turned on, preparation to the return to normal operation mode.
The PCIRST# signal 430 is asserted shortly after the PCLK signal 215 is turned on, initiating a reset of the registers and contents of the first memory controller 210 . The PCIRST# signal 430 remains asserted for a t reset period. In one embodiment, the t reset period is 1 ms. During this time, control of the memory remains with the suspend memory controller 220 .
While PCIRST# signal 430 is asserted, the SUS_STAT# signal 299 is deasserted. The SUS_STAT# signal 299 indicates to the suspend memory controller 220 that the exit from the sleep mode is imminent. In one embodiment, the SUS_STAT# signal 299 is deasserted t refresh prior to the deassertion of the PCIRST# signal 430 . In one embodiment, the t refresh period is 32 μs.
The NREF_EN signal 440 is asserted t restore after the deassertion of the PCIRST# signal 430 . The period t restore is used to restore registers to the state prior to entry into the sleep mode. The NREF_EN signal 440 corresponds to a register written to by the computer system 100 to indicate that the registers are restored. After the NREF_EN signal 440 is asserted, it is guaranteed that the control will transfer to the normal logic within a period of t transfer . In one embodiment, the period t transfer is 32 μs. After the period t ransfer is over, the control is transferred back to the first memory controller.
The SCKE signal 390 is deasserted t delay after the NREF_EN signal 440 is asserted. Because the CKE signal 260 is generated from a logical AND of the SDCKE signal 240 and the SCKE signal 390 , the CKE signal 260 is deasserted concurrently with the SCKE signal 390 . The period t delay is sufficient to complete pending refresh cycles, transfer control from the second memory controller 220 to the first memory controller 210 , and take SDRAM out of self-refresh mode. In one embodiment, the t delay period is 32 μs. After the CKE signal 260 is deasserted, the memory is in normal operation, and the first memory controller 210 is controlling the memory. In one embodiment, when a DRAM access cycle is initiated, the first memory controller transitions from the idle state 510 to the normal state 530 .
The SDCKE signal 240 , the clock enable signal of the first memory controller 210 is high while the first memory controller 210 is in the sleep mode and transitions out of the sleep mode. After the first memory controller 210 exits from the sleep mode, the SDCKE signal 240 remains high, until a new sleep period is initiated.
SDRAM and EDO DRAM Combination Application
The present invention may also be used for a system including both SDRAM and EDO DRAM. FIG. 8 is a flowchart of the entry into and exit from sleep mode for a system including both SDRAM and EDO DRAM, according to the present invention. At block 810 , the computer system is in the normal operation mode.
At block 815 , the system tests whether the SUS_STAT# signal 299 has been asserted. The SUS_STAT# signal 299 initiates entry into the sleep mode. In one embodiment, the SUS_STAT# signal 299 is an active low signal, and therefore it is tested whether SUS_STAT# signal 299 is low. If the SUS_STAT# signal 299 is not low, the system returns to normal operation, at block 810 . In one embodiment, this is an interrupt driven system. Thus, there is no query of the status of the SUS_STAT# signal 299 . Rather, when the SUS_STAT# signal 299 is asserted, an interrupt is sent, and the system moves to block 820 .
At block 820 , all pending refresh cycles are completed. In this way, there are no pending refreshes in the queue when the sleep mode is initiated.
At block 825 , the SDRAM are placed into self-refresh mode. This is accomplished using the process described above with respect to FIG. 6 .
At block 830 , the system determines the type of DRAM in each populated EDO DRAM bank. The two types of DRAM are self-refreshing and non-self-refreshing DRAM. If some of the EDO DRAM is non-self-refreshing, or there is FPM DRAM, the system goes to block 835 . If all of the EDO DRAM is self-refreshing, the system continues to block 840 .
At block 835 , the internal ring oscillator (DOSC) is started. The internal ring oscillator is used to time refresh cycles for non-self-refresh DRAM.
At block 840 , the DRAMs are placed in a self-refresh mode. In the self-refresh mode the DRAMs do not require external signals for clocking. Both blocks 840 and 835 continue to block 845 .
At block 845 , it is tested whether the IN_SUS# signal 255 has been asserted. In one embodiment, the IN_SUS# signal 255 is an active low signal, therefore the system tests whether the IN_SUS# signal 255 is zero. The IN_SUS# signal 255 is asserted by the suspend memory controller 220 when the suspend memory controller 220 has received control from the first memory controller 210 . If the IN_SUS# signal 255 is not asserted, the system returns block 850 . If the IN_SUS signal 255 is asserted, indicating that control has been taken over by the suspend memory controller 220 , the system moves to block 855 .
At block 855 , the first memory controller 210 is in the sleep mode. In this state no clocks are connected to the first memory controller 210 . In one embodiment, power is also removed from the first memory controller, and only the suspend memory controller 220 is powered. The EDO or FPM non-self-refreshing DRAMs, if any are present in the system, are refreshed at regular intervals by the suspend memory controller 220 .
At block 860 , the system queries whether the SUS_STAT# signal 299 is deasserted. The SUS_STAT# signal 299 indicates the exit form the sleep mode. If the SUS_STAT# signal 299 is not deasserted, the system cycles back to block 855 , remains in the sleep mode, and queries again. If the SUS_STAT# signal 299 has been deasserted, the system continues to block 865 , initiating exit from the sleep mode.
At block 865 the system exits from the sleep mode, and returns to the normal operation mode 810 . The process is described above with respect to FIG. 7 .
FIG. 9 is a timing wave form diagram of a refresh cycle in the sleep mode for non-self-refreshing memory banks, including EDO or FPM DRAM banks. Note that FIG. 9 illustrates a time period when the system is in a sleep mode. Only a single refresh cycle is illustrated. The illustrated cycle is repeated at regular intervals. In one embodiment, the interval is determined based on the refresh period of the DRAM used.
A DOSC signal 900 is generated by an internal ring oscillator 340 (DOSC) within the suspend memory controller 220 . The DOSC signal 900 is an oscillator having a period of t osc . The period of the DOSC signal 900 is designed such that t osc >t min , where t min is the minimum time RAS signals 910 - 960 need to be asserted to refresh a row of memory. Thus, RAS signals 910 - 960 are asserted on a rising edge of the DOSC signal 900 and deasserted on the next rising edge. The CAS signal 970 is asserted to initiate a refresh cycle.
Each populated row of RAS 910 , 920 , 930 and 960 is asserted in sequence until all populated RAS 910 , 920 , 930 and 960 have been asserted. The RAS 940 . 950 associated with unpopulated rows, RAS 3 and RAS 4 , are not asserted. In one embodiment, SDRAM and other DRAM may be mixed. Thus, the unpopulated rows RAS 3 940 and RAS 4 950 may be either empty or populated with SDRAM. If any rows are populated by SDRAM, the sequence described in FIG. 6 is used to place the SDRAM in a self-refresh mode.
As can be seen, in the above description, the present invention is able to refresh a memory system which may include SDRAM, self-refreshing EDO/FPM DRAM, and other types of DRAM in a single system. This capability is advantageous as it permits mixing of memory types without losing the benefits of a sleep mode.
In the foregoing specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. The present invention should not be construed as limited by such embodiments and examples, but rather construed according to the following claims.
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A method and apparatus for a memory control system is provided. The memory control system includes a first memory controller designed to access and refresh a DRAM, using a clock, during a first operation mode. The memory control system further includes a second memory controller designed to maintain the DRAM during a second operation mode and to exit from the second operation mode. During the second operation mode a clock or the clock and power is turned off to the first memory controller, and upon returning to the first operation mode, no initialization of the first memory controller is needed. Since a significant proportion of the power is consumed by the first memory controller, power savings results from employing this technique.
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BACKGROUND OF THE INVENTION
[0001] The technology described herein relates generally to gas turbine engine components and more specifically to devices for manually rotating the core of a gas turbine engine.
[0002] Gas turbine engines typically include a compressor, a combustor, and at least one turbine. The compressor may compress air, which may be mixed with fuel and channeled to the combustor. The mixture may then be ignited for generating hot combustion gases, and the combustion gases may be channeled to the turbine. The turbine may extract energy from the combustion gases for powering the compressor, as well as producing useful work to propel an aircraft in flight, such as by driving a fan or propeller, or to power a load, such as an electrical generator.
[0003] The compressor and turbine are linked together via a shaft to form a rotating piece of turbomachinery located inside of a casing. This assembly may be referred to as a “core” of the gas turbine engine. During maintenance or repair operations it is often necessary to inspect blades and other elements of this rotating turbomachinery within the core. However, access to and visibility of this turbomachinery is frequently limited by the casing as well as other elements of the gas turbine engine.
[0004] Many gas turbine engines have one or more inspection ports, openings in the casing, which may be opened via removable plugs or covers to inspect and/or service (repair, replace, adjust, etc.) internal components. Inspection can be visual with the naked eye, or with mirrors or other optical tools such as borescopes. Frequently, however, these inspection ports are positioned such that only certain elements of the rotating turbomachinery are visible with the engine stopped and the turbomachinery in a fixed position. It is therefore often necessary to rotate the turbomachinery to view and/ or service other components.
[0005] Rotation is typically accomplished by applying torque through a drive pad which is connected to an accessory gearbox. A socket is normally provided in the drive pad to receive a ratchet wrench or other hand tool, or an output shaft of a motorized drive unit. Manual operation of the drive pad, however, may prove difficult for an operator who needs to be proximate to an inspection port which may not be adjacent to the drive pad. Therefore, two or more persons may be required to rotate and inspect or service the turbomachinery. Motorized drive units may be operated remotely by an operator who is proximate the inspection port. However, motorized drive units are expensive, often cumbersome, and do not provide the operator with a “feel” for the rotation and momentum of the turbomachinery, making precise positioning and/or reversing of the rotation somewhat difficult and time consuming.
[0006] Accordingly, there remains a need for a device for manually rotating or turning a core of a gas turbine engine which is inexpensive yet portable and easy to use, and enables a single operator to rotate and inspect or service the turbomachinery.
BRIEF DESCRIPTION OF THE INVENTION
[0007] A device for manually rotating a core of a gas turbine engine, said device comprising a drive mechanism, an operator control, and a flexible cable rotatably coupling said drive mechanism and said operator control.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a cross-sectional schematic view of an exemplary gas turbine engine.
[0009] FIG. 2 is a perspective view of an exemplary gas turbine engine having a manual core rotation device installed thereon.
[0010] FIG. 3 is a partial cut-away view of an exemplary drive mechanism of a manual core rotation device.
[0011] FIG. 4 is a perspective view of an exemplary operator control of a manual core rotation device.
DETAILED DESCRIPTION OF THE INVENTION
[0012] FIG. 1 is a schematic illustration of an exemplary gas turbine engine 10 including a fan assembly 12 , a booster 14 , a high pressure compressor 16 , and a combustor 18 . The engine 10 also includes a high pressure turbine 20 , and a low pressure turbine 22 . The fan assembly 12 includes an array of fan blades 24 extending radially outward from a rotor disk 26 . The engine 10 has an intake side 28 and an exhaust side 30 . The engine 10 may be any gas turbine engine. For example, the engine 10 may be, but is not limited to being, a GE90 gas turbine engine available from General Electric Company, Cincinnati, Ohio. The fan assembly 12 , booster 14 , and turbine 22 may be coupled by a first rotor shaft 32 , and the compressor 16 and turbine 20 may be coupled by a second rotor shaft 34 .
[0013] In operation, air flows through the fan assembly 12 and compressed air is supplied to the high pressure compressor 16 through the booster 14 . The highly compressed air is delivered to the combustor 18 , where it is mixed with a fuel and ignited to generate combustion gases. The combustion gases are channeled from the combustor 18 to drive the turbines 20 and 22 . The turbine 22 drives the fan assembly 12 and booster 14 by way of shaft 32 . The turbine 20 drives the compressor 16 by way of shaft 34 . High pressure compressor 16 , turbine 20 , and shaft 34 form a rotating piece of turbomachinery sometimes called a core which may require inspection and/or service from time to time. This turbomachinery is enclosed within an outer casing 70 (identified in FIG. 2 ).
[0014] As shown in FIG. 2 , engine 10 includes a drive pad 20 which provides a mechanical drive connection to the rotating turbomachinery through a gearbox (not labeled). Gearbox and drive pad locations may vary in location and orientation depending upon the particular engine application. Also shown in FIG. 2 is an exemplary manual device 30 for turning the core. Manual core turning device 30 includes a drive mechanism 40 , a flexible drive cable 50 , and an operator control 60 .
[0015] FIG. 3 illustrates in greater detail the elements of the drive mechanism 40 . Drive mechanism 40 includes a coupling feature 41 , an output shaft 42 , a mounting block 49 , a planetary gearbox 53 , and an input shaft 44 .
[0016] In operation, input shaft 44 receives torque from flexible cable 50 , transmits torque through planetary gearbox 53 through mounting block 49 to output shaft 42 and to the drive pad 20 via coupling feature 41 to rotate the turbomachinery within the core of the engine 10 .
[0017] As show in FIG. 3 , additional elements may be included to enhance the operation of the manual core rotation device such as an enunciator to signal rotational position of the engine. Output shaft 42 may be coupled to a secondary shaft 43 through gearset 44 having a suitable gear ratio to rotate secondary shaft 43 one rotation per rotation of the core of the engine 10 . A pin 45 affixed to gearset 44 can be utilized to engage a microswitch 46 to send electric current from battery 47 to an sound emitter 48 and thereby provide an audible indication that the core had undergone a complete rotation (and thus inspection from a fixed reference point would have inspected all rotating elements circumferentially disposed around the core).
[0018] Battery 47 , microswitch 46 , and sound emitter 48 may be of any suitable design and construction, and may be commercially available items. Battery 47 may be a dry cell battery and sound emitter 48 may be a bell, buzzer, or horn of suitable sound production characteristics so as to be readily heard by the operator in the desired location. Other locations for the enunciator are possible, such as proximate to the operator control, so long as the enunciator provides a desired indication of the engine rotation.
[0019] Planetary gearbox 53 may provide any desired gear ratio between the output shaft 42 and the input shaft 44 . Having a gear ratio such that one turn of the input shaft 44 produces less than a full rotation of output shaft 42 may reduce the level of manual effort required to rotate the core and also enable finer control over the rotational position of the core for inspection and/or service operations. Ratios of 10 to 1 may be useful for certain engine applications, and may be specified so as to achieve a desired level of operator effort to rotate the core, such as approximate values on the order of 80 inch pounds. Higher (numerically) gear ratios may be needed for larger engines to reduce the rotational effort required.
[0020] Mounting block 49 may be of any suitable size, shape, material, and construction for mating the output shaft 42 and coupling 41 to the drive pad 20 of the engine 10 . It may be desirable to fabricate the mounting block 49 from, or coat mounting block 49 with, a non-stick and non-marring material such as tetrafluoroethylene or polytetrafluoroethylene, which is commercially available under the trade name TEFLON® from DuPont. Mounting block 49 may have any suitable mounting configuration, such as holes or slots to engage complementary features on the engine 10 to hold the drive mechanism in place and may utilize bolts or screws for securement.
[0021] As shown in FIG. 4 , the operator control 60 includes a mounting device 61 and a wheel type device 62 for controlling the rotation of the core. The wheel 62 also includes a knob 63 to provide for increased operator control over the rotation of the wheel 62 . The wheel 62 is affixed to the flexible cable 50 through any suitable conventional coupling. Although a wheel 62 is shown, any type of device may be provided for operator use or, if desired, a tool engagement feature may be provided such that the operator can use a conventional tool such as a ratchet wrench.
[0022] Mounting device 61 can be of any conventional construction suitable for securing operator control 60 in a fixed position, such as affixed to the gas turbine engine, an engine holding fixture, an engine accessory or element such as a pipe or tube, or an engine nacelle or pylon (if the engine is serviced on the aircraft). Clamps or brackets may be used as required to hold the operator control, and may provide for adjustment or movement to another location as required. The operator control may be positioned as desired by the operator to provide for ease of rotation and control of rotation, as well as visibility to the inspection ports or other items the operator needs to view or operate such as service or repair tooling.
[0023] Elements of the manual core rotation device may be fabricated from any suitable materials, and may incorporate standard commercially-available items or materials as desired. In particular, the cable may be any type of flexible cable which is suitable in length and flexibility for the intended application. Spring cables as well as solid cables may be suitable for this low speed, comparatively low torque application.
[0024] The manual core rotation device may also be provided as an assembly in kit form, with one or more different mounting blocks adapted to be used with various engines and engine configurations. A carrying case may be provided for ease of storage and transportation of the device. The device may be self-contained, without requiring any external power supply or support equipment, and therefore provides a high degree of portability. It may also be suitable for use in a wide range of internal and external operating environments, and may be fabricated so as to be weather resistant as well.
[0025] Manual core rotation devices of the type described herein may be useful in other installations besides gas turbine engines. For example, such devices may be utilized in the automotive field or any other field where it is desired to rotate machinery from a remote location. With regard to gas turbine engines, applications may include aircraft type applications as well as land based or marine applications.
[0026] While this application has described various specific exemplary embodiments, those skilled in the art will recognize that those exemplary embodiments can be practiced with modification within the spirit and scope of the claims.
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A device for manually rotating a core of a gas turbine engine, said device comprising a drive mechanism, an operator control, and a flexible cable rotatably coupling said drive mechanism and said operator control.
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CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 12/827,545, filed on Jun. 30, 2010, which claims priority to and the benefit of U.S. Provisional Patent Application No. 61/270,342, filed on Jul. 7, 2009, the entire disclosure of each of which is incorporated by reference herein.
FIELD OF THE INVENTION
The present invention relates to electronic driver circuits, and more particularly, to low power electronic driver circuits having low manufacturing costs.
SUMMARY OF THE INVENTION
Logic circuits have been constructed from many different transistor types. The preferred type at present for portable devices is CMOS. Bipolar circuits, such as TTL or RTL, are very fast but consume much power. This is because current is flowing continuously. TTL will typically utilize PNP and NPN type bipolar transistors. CMOS utilizes two transistor types: NMOS and PMOS. The advantage to CMOS is that only one of two transistors is switched on at a time resulting in a circuit in which current flows only when the logic state is switching. Certain capacitances in the circuit (e.g., the gate of the MOS devices) can result in slower operation, but power consumption is low. A disadvantage to these approaches is that of the multiple transistor types, each can require a large number of processing steps and photolithography masks to manufacture. Multiple types means multiple large sets of processing steps and expensive masks.
The present invention is a circuit design that utilizes two transistor types that can be manufactured together thereby reducing the number of processing steps and masks and resulting in lower cost.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a prior art driver circuit using CMOS logic.
FIG. 2 illustrates a prior art, RTL driver circuit using bipolar logic.
FIG. 3 illustrates a prior art driver circuit using NMOS logic.
FIG. 4 illustrates a driver circuit according to the present invention.
FIG. 5 illustrates a driver circuit according to the present invention with output amplification.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Logic circuits have been constructed from many different transistor types. FIG. 1 depicts a prior art CMOS logic device (an inverter). The device is simple in design having just an NMOS 100 and a PMOS 101 transistor. When the input is high, the NMOS transistor 100 is switched on and the PMOS transistor 101 is switched off; with the NMOS transistor 100 switched on, the output is connected through the NMOS transistor 100 to ground. When the input is low, the PMOS transistor 101 is switched on and the NMOS transistor 100 is switched off; with the PMOS transistor 101 switched on, the output is connected through the PMOS transistor 101 to the positive supply. Since the NMOS 100 and PMOS transistor 101 are not on simultaneously (except for a moment during transition of the input from high to low or low to high), current does not flow in the circuit except during switching. Even at the output, given the typical case where the output is connected to the input of another similar device, current only flows through the switched on NMOS 100 or PMOS transistor 101 during transition so as to charge or discharge the MOS transistor gates of the subsequent stages.
With a bipolar circuit, as is depicted in FIG. 2 , current typically flows from stage to stage as a function of the logic state. In FIG. 2 , a RTL inverter will consume no power when the input is high as this will reverse bias the base junction of PNP transistor 110 resulting in that transistor being switched off. However, when the input is low, current flows from the positive supply through the emitter and base connections and to the low input source; current also flows from the positive supply through the transistor 110 and through resistor 111 to ground resulting in a high voltage at the output. In a typical case where the output is connected to the input of a similar circuit, when current is flowing through the first circuit resulting in a high output, the transistor of a subsequent circuit will be switched off. However, when the input is high to the first circuit and the current if not flowing, the output will be low and a subsequent circuit will have current flowing from the positive supply through the emitter-base junction and back into the resistor of the prior circuit. Current typically is flowing somewhere all the time. The same is generally true for RTL constructed from NPN transistors and for TTL logic. One advantage to RTL is that is can be made from a single transistor type (NPN or PNP).
What is needed is a logic design in which only one transistor type is used and current generally does not continuously flow. One such design is shown in FIG. 3 . In this MOS design, only NMOS transistors are used. The output is controlled by NMOS transistor 120 . A problem presented here is that in order to pass the voltage level of the supply to the output, the voltage on the gate of NMOS transistor 120 must exceed the voltage to be provided to the output by the threshold voltage (V th ) of the NMOS transistor 120 . To achieve this, assuming that the highest available voltage is the supply voltage, the gate voltage must be generated by the circuit. In this case, the voltage on the gate of NMOS transistor 120 is generated in stages. First, the largest available voltage (the supply voltage) is applied to the precharge (PRCH) input through diode 121 while the boost (BOOST) and reset (RST) inputs are held low. Then, the boost input is raised and the rising edge is capacitively coupled through NMOS transistor 122 which is wire up as a capacitor. The capacitively coupled boost voltage will raise the voltage on the gate resulting from the precharge input up to a new higher voltage that will enable the output NMOS transistor 120 to pass the desired voltage to the output. To switch off the output, the precharge input must first be lowered and then the reset input (RST) raised; this will dump the charge from the gate of NMOS transistor 120 through reset NMOS transistor 123 to ground, thereby switching off the output NMOS transistor 120 . The disadvantage is that the series of steps to switch on and off the various inputs results in slower operation. (Similar circuits can be constructed using opposite voltage polarities and PMOS transistors.)
The present invention is a combination of bipolar logic and MOS logic. FIG. 4 depicts a bipolar-MOS type circuit. In this circuit, output PNP transistor 131 will provide a voltage pulse to the output that can be within the emitter-collector saturation voltage (V CESAT ) of the positive supply. This is accomplished by connecting the base of PNP transistor 131 through enable NMOS transistor 132 to NMOS transistor 133 which is wired up as a capacitor; the current will flow from the positive supply through the emitter-base junction of PNP transistor 131 and into capacitor 133 until that capacitor is fully charged. The size of capacitor 133 determines the duration of this current pulse. While this current pulse is flowing, current will flow to the output in an amplified amount as a function of the gain (i.e., the transistor Beta, β) of PNP transistor 131 . When capacitor 133 is charged, the current through PNP transistor 131 stops flowing. The enable NMOS transistor 132 is turned on by raising the voltage on the enable input (EN). The circuit is reset by lowering the voltage on the enable input (EN) and then raising the voltage on reset input (RST) which will cause the charge on reset NMOS transistor 134 to be dumped to ground. Because PNP transistor 131 is switched on by lowering the voltage on its base, no boost voltage level is required and the two steps of precharging and then boosting as is required for the circuit depicted in FIG. 3 is replaced by the single step of raising the enable input in the circuit depicted in FIG. 4 . This results in greater speed in operation. Furthermore, since the current only flows when the enable input (EN) is first raised (i.e., until capacitor 133 is charged), the power consumed is similar to that of a CMOS circuit (i.e., current only flows during switching while the gate of a MOS transistor is being charged). Also, the output voltage pulse can come to within V CESAT of the supply voltage without boost circuitry. (Similar circuits can be constructed using opposite voltage polarities and PMOS and NPN transistors.)
A variation on the circuit of FIG. 4 , would be to eliminate the capacitor (transistor 133 ) and connect enable NMOS transistor 132 directly between the base of PNP transistor 131 and ground (eliminating the capacitor 133 also eliminates the requirement for a reset transistor 134 as well). While this variation will consume more power for the static current path from the supply voltage through PNP transistor 131 and enable NMOS transistor 132 to ground, it is a simpler circuit that can be operated for longer than just the time to charge the capacitor (transistor 133 ). Alternatively, reset NMOS transistor 134 could be switched on while enable input (EN) is high thereby bypassing capacitor transistor 133 to accomplish the same effect.
FIG. 5 depicts an identical circuit to that depicted in FIG. 4 except that the output has increased gain. In this instance, the current to the output is increased by an additional β multiplier (of secondary output NPN transistor 135 ) in a darlington-like configuration. The tradeoff is that the maximum output voltage is an additional V f lower than that of the circuit of FIG. 4 due to the forward voltage drop (V f ) of the base-emitter junction of NPN transistor 135 .
The present invention can be manufactured using standard processes. In the course of manufacturing the MOS transistors, polysilicon gate material is deposited and this is then patterned and etched and then dopants are implanted. With the present invention, some of the polysilicon material deposited to form the MOS gates can be patterned and etched to remain above areas that are just field oxide or the like. Then, when implanting the MOS transistors, this poly can be implanted to form the PNP transistors at the same time. When contacts to the MOS gates are formed, contacts to the base, emitter and collectors of the PNP transistors can also be formed at the same time.
Furthermore, the present invention can be used in a variety of circuits. In particular, embodiments of the present invention can be used in the design of devices such as memory products, and in particular non-volatile memory products, for portable devices wherein low power is desirable as well as other devices wherein low power may not be as necessary. The present invention can be implemented with cross point memory arrays wherein the memory arrays' surrounding circuitry is also implemented with embodiments of the present invention; these arrays may be one of many tiles or sub-arrays in a larger device or an array within a 3-D arrangement of arrays or tiles. In such a memory device, the storage cells can incorporate field-emitters, diodes or other non-linear conductor devices that conduct current better in one direction than the other for a given applied voltage. The storage element can be a fuse, an antifuse, a phase-change material such as a Chalcogenide (including a Chalcogenide in which the programmed resistivity can be one of two resistance values and, in the case of more than one bit per cell storage cells, in which the programmed resistivity can be one of three or more resistance values), a resistance that can be electrically altered, or a field-emitter element programming mechanism including an element for which the resistance or the volume is changeable and programmable.
The bipolar-MOS driver of the present invention will find applications in array circuits such as a memory array, display array, and the like. In such array applications, the mechanism to control the voltage on the enable input (EN) can be implemented as is done in U.S. patent application Ser. No. 11/926,778 and this Allowed patent application Ser. No. 11/926,778 is hereby included herein by reference in its entirety. In that allowed patent application Ser. No. 11/926,778, the gates of the MOS drivers on a plurality of row lines (said plurality comprising either all of the rows or a subset of the rows) of the array are all charged by a precharge mechanism and then all but one driver is discharged by means of a binary diode decoder/selector array (using diodes or some other non-linear current steering devices) thereby leaving one driver enabled. In the present invention, a plurality of driver bipolar transistor 131 /enable MOS transistor 133 pairs associated with a plurality of row lines of the array (said plurality comprising either all of the rows or a subset of the rows of the array) could be activated by charging the base of every enable MOS transistor 133 of the plurality (but, typically while the supply voltage is switched off by a switching means, said means not shown in FIG. 4 , but that is well understood by those skilled in the art) and then all but one enable MOS transistor 133 is discharged by means of a binary diode decoder/selector array (using diodes or some other non-linear current steering devices or other decoding selection means) thereby leaving only one driver enabled. After such a precharge and then all-but-one disabling of drivers, the supply voltage could be switched on. (Of course, the row lines could be column lines if the array were rotated 90 degrees.)
Memory devices incorporating embodiments of the present invention may be applied to memory devices and systems for storing digital text, digital books, digital music (such as MP3 players and cellular telephones), digital audio, digital photographs (wherein one or more digital still images can be stored including sequences of digital images), digital video (such as personal entertainment devices), digital cartography (wherein one or more digital maps can be stored, such as GPS devices), and any other digital or digitized information as well as any combinations thereof. Devices incorporating embodiments of the present invention may be embedded or removable, and may be interchangeable among other devices that can access the data therein. Embodiments of the invention may be packaged in any variety of industry-standard form factor, including Compact Flash, Secure Digital, MultiMedia Cards, PCMCIA Cards, Memory Stick, any of a large variety of integrated circuit packages including Ball Grid Arrays, Dual In-Line Packages (DIP's), SOIC's, PLCC, TQFP's and the like, as well as in proprietary form factors and custom designed packages. These packages can contain just the memory chip, multiple memory chips, one or more memory chips along with other logic devices or other storage devices such as PLD's, PLA's, micro-controllers, microprocessors, controller chips or chip-sets or other custom or standard circuitry.
Many variations come to mind in light of the present teaching. These include using any combination of switch devices that can be manufactured in parallel, or mostly or generally in parallel, in a semiconductor fabrication facility (fab).
The foregoing description of and examples of the preferred embodiment of the invention and the variations thereon have been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching. It is intended that the scope of the invention be limited not by this detailed description.
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The present invention relates to electronic driver circuits, and more particularly, to low power electronic driver circuits having low manufacturing costs. The present invention is a circuit design that utilizes two transistor types that can be manufactured together thereby reducing the number of processing steps and masks and resulting in lower cost.
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RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application Ser. No. 60/495,083 filed on Aug. 13, 2003 under 35 U.S.C. § 119(e) and incorporates by reference the content of the provisional application in its entirety.
FIELD OF INVENTION
This invention pertains generally to maintenance of aquatic facilities and particularly to sanitizing and/or oxidizing an aquatic facility.
BACKGROUND
Aquatic facilities, such as swimming pools, become contaminated from various components in the environment such as dust, bacteria, and viruses, as well as from waste products produced by the bathers. To ensure that the pools can be enjoyed safely, the pool water is treated to reduce or eliminate chemical oxygen demand (COD) and/or total organic carbon (TOC) in the water. Typically, chlorine or bromine is used to disinfect the water and prevent viruses and bacteria from being transmitted among the bathers. Halogen donor compounds such as chlorine or bromine are also used to sanitize/oxidize waste products produced by the bathers.
To achieve an effective level of antimicrobial and viricidal activity, the oxidation potential of water must be sustained above a threshold value. Sustaining the oxidation potential is an uphill battle, as the oxidation potential is continuously reduced by contaminants' consumption of the sanitizing/oxidizing agent. Studies have confirmed that the effectiveness of chlorine/bromine-based sanitizers is significantly reduced with increased contaminant level. As used herein, the “contaminant” is any substance that reacts with and consumes the sanitizing/oxidizing agent. In swimming pool and other waters, contaminants often come in the form of organic compounds.
Sanitizing water would be relatively easy if the only type of contaminants were inorganic nitrogen waste products (e.g., ammonia, ammonium), as chlorine can convert the ammonia to inert nitrogen gas using the well known breakpoint chlorination process. However, when the water also contains organic nitrogen waste products, the breakpoint chlorination process is significantly impaired. This impairment is at least partly due to the fact that organic nitrogen reacts with the sanitizing agent in a less desirable competing reaction. The competing reaction entails chlorine's reaction with the organic nitrogen to produce a volatile and irritating byproduct known as chloramine (NH 2 Cl, NHCl 2 , NCl 3 , R 2 NCl, RHNCl, where R represents organic constituent). Because some of the chlorine is turned into chloramines by the organic nitrogen (instead of being turned into inert nitrogen by the inorganic nitrogen), the ability of chlorine (or other halogen)-based sanitizing/oxidizing agent to rid the water of inorganic nitrogen such as mono- and di-chloroamines is significantly impaired.
In applications such as swimming pool water, where both organic and inorganic nitrogen are present, organic nitrogen that forms chloramines competes for chlorine against inorganic nitrogen that forms inert nitrogen. Chloramines accumulate because chlorine is consumed more readily by the organic byproducts than the already partially oxidized chloramines. Accumulation of chloramines is undesirable for a number of reasons. First, chloramines are less effective as oxidizers than chlorine. Second, incomplete oxidation of the Total Organic Carbon (TOC) by reaction with chlorine produces trihalomethane (THM), which are known carcinogens. Furthermore, chloramines and THM induce corrosion of metals and impose mild to severe irritation to bathers' eyes, skin, and respiratory systems.
To control disinfection rates and prevent the accumulation of chloramines, the organic byproducts must be effectively oxidized independently of chlorine, leaving chlorine free to react with the inorganic nitrogen. This way, the chlorine is free to disinfect the water by converting the inorganic nitrogen to inert nitrogen gas. Also, when the TOC is diminished, the potential for formation of THM by reaction between chlorine and the TOC is reduced. Thus, a method and composition for achieving breakpoint chlorination without accumulation of chloramines and formation of incomplete oxidation products is desired.
SUMMARY
The invention includes a water treatment product that effectively reduces the amount of organic and inorganic nitrogen by preventing the accumulation of chloramines. The water treatment product contains a much lower level of irritants than most currently available water treatment products, allowing water treatment even while bathers are in the swimming pool.
In one aspect, the invention is a water treatment composition includes a potassium monopersulfate component, a halogen component including or generating a halogen donor, and a barrier film. The barrier film, which allows the potassium monopersulfate component to be combined with the halogen component, includes one or more of an inorganic salt, silicate, borosilicate, and an organic polymer. In another aspect, the invention is a method of preparing a water treatment composition by providing a potassium monopersulfate component and combining the potassium monopersulfate component with a halogen donor and a barrier film.
In yet another aspect, the invention is a method of treating water by obtaining a solid product containing potassium monopersulfate and a halogen donor, and periodically adding the mixture to a body of water.
The invention is also a method of combining potassium monopersulfate and a halogen donor into a stable product. Potassium monopersulfate and halogen donor(s) were previously not combined because of their incompatibility. The invention includes coating either the potassium monopersulfate with one or more of inorganic salt, silicate, borosilicate, and organic polymer to overcome this incompatibility. After the coating, the halogen donor is added to the coated potassium monopersulfate to form a PMPS-halogen product.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Embodiments of the invention are described herein in the context of a swimming pool, and particularly in the context of disinfecting the swimming pool water. However, it is to be understood that the embodiments provided herein are just preferred embodiments, and the scope of the invention is not limited to the applications or the embodiments disclosed herein.
Due to the above-mentioned disadvantages of using a halogen to treat water that contains both organic and inorganic contaminants, potassium monopersulfate (KHSO 5 , herein referred to as PMPS) is sometimes used with halogen. PMPS is effective at removing TOC and prevents the accumulation of chloramines by allowing them to be oxidized via breakpoint chlorination. Also, unlike chlorine, PMPS does not produce THMs.
However, PMPS has its disadvantages as well. For example, PMPS is usually accompanied by an irritating byproduct, K 2 S 2 O 8 (potassium oxodisulfate). Since bathers can tolerate only a low level of K 2 S 2 O 8 , there is naturally a limit to how much PMPS can be added to a body of water. In applications such as swimming pools where the product may come into direct contact with bathers, PMPS is added as part of a shock treatment whereby an entire dosage is spread across the surface of the pool at once. The dosage is limited to 1˜2 lb/10,000 gallons per week, depending on the manufacturer. If this limit were to be exceeded, bathers are likely to experience irritation due to accumulation of K 2 S 2 O 8 , which has a long half-life. Thus, this dosage cannot be exceeded regardless of how contaminated the pool water is. Moreoever, the presence of the irritant means the PMPS treatment must be performed when bathers are not present. Most manufacturers of PMPS-based pool treatment compositions require bathers to wait at least 30 minutes before using the pool after the treatment.
The periodic shock treatment does not provide for sustained disinfection, and undesirably allows the water quality to fall between treatments. Between PMPS treatments, the organic and inorganic nitrogen in the water trigger competing reactions on the sanitizing/oxidizing agent, thereby impairing the disinfection rate. Also, the competing reactions between accumulated organics and nitrogen for the sanitizing/oxidizing agent allow for increased levels of chloramines which impair both water and air quality.
To address these issues, attempts have been made to use PMPS in conjunction with a sanitizing agent, such as a halogen donor. However, a problem with PMPS-and-halogen-based water treatment is that PMPS is not compatible with some of the chlorine/bromine donor products that are most commonly used today (e.g., calcium hypochlorite, dichloro isocyanurate, trichloro-isocyanurate, bromo-chloro-dimethylhydantoin (BCDMH), dibromo-dimethylhydantoin (DBDMH). Thus, to use PMPS with a halogen, sophisticated control and applications technologies are need to be implemented to allow for more frequent feed of PMPS while bathers are present. Due to the incompatibility between PMPS and halogen, these technologies feed the sanitizer and the PMPS separately, and usually independently (e.g., see U.S. Pat. Nos. 6,620,315, 6,409,926, 6,143,184). In these processes, expensive chemical feed and control technology is required along with extensive on-site maintenance and expertise to tune in or optimize the sequencing of the chemicals being fed.
The invention includes a PMPS-halogen product including PMPS and one or more halogen donors. The product overcomes the incompatibility problem between the PMPS and halogen donors by implementing a barrier film between the PMPS and halogen donor(s) which allows the PMPS and the halogen donor to be combined into a stable composition. Preferably, the product uses a PMPS that is substantially free of K 2 S 2 O 8 so that more of the product can be used without posing a health hazard to the bathers. The PMPS-halogen product frees up the halogen to react with inorganic wastes by having PMPS remove organic wastes.
The halogen-PMPS composition contains 1) a halogen component that includes or produces a halogen donor, 2) a PMPS component having the formula (KHSO 5 ) x (KHSO 4 ) y (K 2 SO 4 ) z , where x+y+z=1, x=0.43–0.75, y=0.01–0.40, z=0.01–0.40, and a K2S2O8<0.5 wt %, and 3) a barrier film between the PMPS and the halogen components. The weight fractions of the PMPS component, the halogen component, and barrier film are about 4–70.8 wt. %, about 29–95.8 wt. %, and about 0.2–10 wt. %, respectively. This halogen-PMPS composition enhances disinfection rates by sustaining higher oxidation-reduction potential (ORP) values in water that is being treated. Furthermore, this halogen-PMPS composition promotes breakpoint chlorination of organic nitrogen and of inorganic nitrogen in the presence of organic chemical oxygen demand (COD).
In one embodiment, the PMPS component has the formula (KHSO 5 ) x (KHSO 4 ) y (K 2 SO 4 ) z , where x+y+z=1, where x=0.42–0.64, y=0.15–0.40, and z=0.15–0.40. In another embodiment, the PMPS component has the formula (KHSO 5 ) x (KHSO 4 ) y (K 2 SO 4 ) z , where x+y+z=1, where x=0.48–0.64, y=0.15–0.37, and z=0.15–0.37. The process for preparing this PMPS component is described in U.S. Provisional Patent Application Ser. No. 60/505,466, which is incorporated by reference herein in its entirety.
The PMPS component of the PMPS-halogen product is made of about 43 to about 76 wt. % KHSO 5 , less than about 0.5 wt. % (and preferably less than about 0.2 wt. %) of K 2 S 2 O 8 , and sometimes also alkali magnesium salt. Depending on the embodiment, there may be no alkali magnesium salt in the product. The alkali magnesium salt comprises one or more of Mg(OH) 2 , MgCO 3 , Mg(HCO 3 ) 2 , MgO, (MgCO 3 ) 4 —Mg(OH) 2 -5H 2 O, CaMg(CO 3 ) 2 , MgO—CaO, Ca(OH) 2 —MgO or combinations thereof.
The halogen component is a substance that includes or generates a halogen donor, such as one or more of calcium hypochlorite, trichloroisocyanurate, dichloroisocyanurate, lithium hypochlorite, dibromo-dimethylhydantoin, bromo-chloro-dimethylhydantoin, sodium bromide, and sodium chloride.
The barrier film, which may be an inorganic salt, silicate, borosilicate, an organic polymer, or any combination thereof, allows the halogen donor and the PMPS composition to be combined. The inorganic salt may be one or more of sodium, potassium, magnesium, calcium, or a combination thereof, combined with one or more of carbonate, bicarbonate, hydroxide, oxide, silicate, borate, or combinations thereof. The silicate may be sodium, potassium, lithium, silicate, borosilicate, or a combination thereof. The organic polymer comprises chitin, chitosan, polymaleic acid, phosphinocarboxylic acid, carboxylate-sulfonate copolymer, a carboxylate-sulfonate terpolymer, or a combination thereof. The carboxylate component of the carboxylate-sulfonate copolymer or the carboxylate-sulfonate terpolymer is derived from either polyacrylic acid, polymethacrylic acid or polymaleic acid, and the sulfonate portion of the carboxylate-sulfonate copolymer or the carboxylate-sulfonate terpolymer is derived from an aliphatic or aromatic compound. The aliphatic compound comprises methacrylamido methyl propane sulfonic acid, and the aromatic compound comprises styrene sulfonic acid. The terpolymer incorporates a nonionic component such as (meth)acrylamide, substituted (meth)acrylamide, vinyl alcohol, allyl alcohol, vinyl esters, an ester of vinyl or allyl alcohol, styrene, isobutylene or diisobutylene.
The barrier film may be coated onto either the halogen donor or the PMPS composition. The barrier film may be coated by covering the composition with the barrier film material while mechanically mixing the barrier film material in a screw auger or a rotary drum. Alternatively, the barrier film may be applied by using a fluidized driver. If the barrier film material is an inorganic salt, it may be applied before, during, or after the drying of the composition. If the barrier film material is silicate, borosilicate, and/or organic polymer, on the other hand, it is preferably applied to the composition either while the composition is drying or after the composition is dried. The coating is then applied in the form of a foam or atomized spray to maximize distribution, and further dried by using a suitable conventional drier including but not limited to a rotary drier or a fluidized drier.
A halogen-PMPS product containing the PMPS composition and one or more of the halogen donors can effectively control the chloramine, COD, and TOC levels in the treated water and reduce or even eliminate the problems associated with the accumulation of these undesirable products. Further, the halogen-PMPS composition reduces or eliminates any byproducts resulting from incomplete oxidation of the waste. This composition may be in powder form, granular form, or in the shape of a pellet, nugget, tablet, sphere, briquette, puck, etc.
The halogen component functioning as the halogen oxidizer may be calcium hypochlorite, trichloroisocyanurate, dichloroisocyanurate, lithium hypochlorite, dibromo-dimethylhydantoin, bromo-chloro-dimethylhydantoin, sodium bromide, sodium chloride, or a combination thereof.
The PMPS compound used for the PMPS-halogen product has a K 2 S 2 O 8 byproduct concentration below 0.5 wt. % and preferably below 0.2 wt. %. The low K 2 S 2 O 8 concentration allows the PMPS-halogen product to be used at a higher dosage than what is currently allowed. In fact, the PMPS-halogen product may be used continually while the pool is being used.
The composition can then be shaped into a useful solid form by using established processing techniques. If the composition is granular, it may be produced using rotary mixers and/or rotary driers. Alternatively, a spray graining technique may be used with a fluidized drier. If the composition is a tablet, a nugget, a briquette, a sphere, a puck or a solid object of a different shape, it may be produced by combining and mixing the components of the composition and applying pressure to a mold or extruding the objects of the desired shape. Optionally, a well-known binding agent may be used to enhance the cohesiveness of the particles. The pressure level that is applied during extrusion may be adjusted according to the desired hardness of the end product.
The shaped composition (e.g., a tablet) is inserted into a feeder or a strainer at any location in the pool, or into a pool circulating system that is continuously or periodically immersed in the water to be treated. The PMPS-halogen product is preferably released in a controlled manner. Besides a tablet, some exemplary shapes for the PMPS-halogen product include powder, granules, nugget, briquette, pucks, etc.—anything deemed suitable by a person skilled in the art. The disclosed stable composition can then be employed in water treatment applications as an improved disinfectant.
The PMPS-halogen product may be used in a liquid form. To prepare the liquid form of PMPS-halogen product, the solid form of PMPS-halogen product is dissolved in water using any number of dry product feed devices. For example, a tank with a mixer and a pump may be used. Alternatively, a chemical feeder which contains the PMPS composition may be used to dissolve some or all of the composition before using the solution. Using the chemical feed, the composition may be applied by periodically using a timer, or by manually or automatically activating the feed system. The method allows for frequent incremental feed or continuous feed of the composition even when bathers are present, without concern of causing irritation. “Frequent incremental feed,” as used herein, refers to a feed of at least one cycle per day.
When the PMPS-halogen composition is used to treat water that contains bathers' waste, the concentration of chloramines and other undesirable byproducts is sustained at much lower levels than when the components of the composition are used separately. Furthermore, when the pool water is “shock” treated by addition of the powder or granular composition across the surface of the pool, the combined level of chlorine and other undesirable contaminants is reduced to a level much lower than that achieved using current methods of shock treatment or breakpoint chlorination. Also, with the halogen-PMPS composition of the invention, there is no need for an oxidation reduction potential (ORP) control device of the type disclosed in U.S. Pat. No. 6,620,315.
Optionally, various other additives such as pH buffering agents, coagulants, clarifiers, algae control agents (e.g., boron or lanthanum based additives) may be included in the halogen-PMPS composition without deviating from the scope of this invention.
Although preferred embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that many variations and/or modifications of the basic inventive concepts herein taught which may appear to those skilled in the present art will still fall within the spirit and scope of the present invention.
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A product including potassium monopersulfate and a halogen is presented. The product is useful for treatment of aquatic facilities such as swimming pools. While it was known that using a combination of potassium monopersulfate and halogen is effective for sanitizing water, a product that includes both components could not be made because of the incompatibility between the two components. The product overcomes the incompatibility by use of a barrier film between the two components. The barrier film, which includes one or more of inorganic salt, silicate, borosilicate, and organic polymer, is coated onto one of the components prior to being combined with the second component. The product may be extruded and molded into a desired shape and added to the water to be treated, as needed.
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BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates generally to outdoor electrical device covers and more particularly to a watertight dual mount cover having haspways for engagement by a padlock shackle or other securement mechanism.
2. Antecedents of the Invention
Dual mount covers for outdoor electrical devices provided for lid hinge connections either on the top of a rectangular base for vertical mounting, or on the side of the base which was then rotated 90 degrees, for horizontal mounting, as exemplified in U.S. Pat. No. 6,642,453 B2.
Among the problems encountered with dual mount covers was that the generally did not provide for securing the cover, hence the electrical device, against unauthorized access. While registered hasp openings for a padlock and the like have been provided on cover assemblies, as illustrated in U.S. Pat. No. 8,314,334 and U.S. Pat. No. 7,728,226, the were formed on forwardly projecting flanges and created a potential hazard of catching or snagging on one's clothing and were generally conspicuous, especially when not employed for securing the lid in a closed position. This problem was exacerbated when the cover was a dual use cover because two diagonally positioned flanges were then required to project from the cover base and only one could possibly be employed.
SUMMARY OF THE INVENTION
A secure dual mount cover for outdoor electrical devices includes a rectangular base having a rear panel as well as top, side and bottom panels. A laterally projecting peripheral flange surrounds the proximal edges of the base. Haspways are provided in diagonally opposed corners of the base flange, with the haspways being closed by an integral web molded in one piece with the base prior to on site assembly.
A lid is hinged to the top panel, for orientation in a vertical mount position or to an orthogonal side panel (with the side panel now on top), for orientation in a horizontal mount position. An aperture at a lower corner of the lid will register with a lower haspway of the base flange, in either vertical or horizontal orientation, when the lid is closed. To secure the cover in a closed position, the lower haspway web is broken so that a security member such as padlock shackle, a bolt, a plastic or wire seal or band, etc., can be inserted through the registered open haspway and lid aperture. The haspway at the upper corner of the base flange remains closed by the web to preclude the entrance of water into the interior of the cover.
As such, the interior of the dual mount cover will be sealed against water penetration through the uppermost haspway by the unbroken web.
From the foregoing compendium, it will be appreciated that an aspect of the present invention is to provide a dual mount cover for outdoor electrical devices of the general character described which is not subject to the foregoing disadvantages of the antecedents of the invention.
A feature of the present invention is to provide a secure dual mount cover for outdoor electrical devices of the general character described which is simple to assemble and easy to use.
A consideration of the present invention is to provide a secure dual mount cover for outdoor electrical devices of the general character described which is well suited for extreme weather conditions.
A further aspect of the present invention is to provide a secure dual mount cover for outdoor electrical devices of the general character described which is well suited for economical mass production fabrication.
A still further consideration of the present invention is to provide a secure dual mount cover for outdoor electrical devices of the general character described wherein padlock shackle haspways are smoothly integrated into the structure of a base or base without the necessity of employing projecting flanges.
Another feature of the present invention is to provide a secure dual mount cover for outdoor electrical devices of the general character described which incorporates inconspicuous haspways for securing a lid in a closed position.
An additional consideration of the present invention is to provide a secure dual mount cover for outdoor electrical devices of the general character described wherein haspways are maintained watertight by an integral web one of which may be broken away for employment in securing the cover against unauthorized access.
To provide a secure dual mount cover for outdoor electrical devices of the general character described wherein a lid may be mounted to either of a pair of orthogonal hinge assemblies while water entry from an unemployed haspway is precluded is a further consideration of the present invention.
Other aspects, features and considerations of the present invention in part will be obvious and in part will be pointed out hereinafter.
With these ends in view, the invention finds embodiment in various combinations of elements, arrangements of parts and series of steps by which the above-mentioned aspects, features and considerations and certain other aspects, features and considerations are attained, or with reference to the accompanying drawings and the scope of which will be more particularly pointed out and indicated in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings, wherein some of the various possible exemplary embodiments of the invention are shown:
FIG. 1 is an isometric view of a secure dual mount cover for outdoor electrical devices constructed in accordance with and embodying the present invention showing a lid hinged to a base oriented in a vertical mount position;
FIG. 2 a front isometric view, similar to FIG. 1 , with the lid in open position and showing a lower haspway opening formed in a flange of a base by breaking an integral closure web and an upper left closed haspway wherein the web is unbroken;
FIG. 3 is a rear elevational exploded view of the dual mount cover showing the lower right haspway opening;
FIG. 4 is a side elevational exploded view of the dual mount cover;
FIG. 5 is a sectional view taken along the plane 5 - 5 of FIG. 4 ;
FIG. 6 is an enlarged scale sectional view taken along the plane 6 - 6 of FIG. 1 , with components deleted for clarity and showing a latch mechanism for securing the lid in a closed position;
FIG. 7 is an enlarged scale rear elevation view of the dual mount cover in a horizontal mount position, with the lid hinged to a side panel of the base and showing an open lower haspway formed by breaking an integral closure web and an upper closed haspway, wherein the web is unbroken;
FIG. 8 is a front elevational view of the dual mount cover in the vertical mount position, with portions deleted for clarity;
FIG. 9 is an enlarged scale sectional view through an open lower haspway, the same being taken along the plane 9 - 9 of FIG. 8 ; and
FIG. 10 is an enlarged scale sectional view through a closed upper haspway, the same being taken along the plane 10 - 10 of FIG. 8 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present invention will now be described in detail with reference to the drawings, which are provided as illustrative examples of the invention so as to enable those skilled in the art to practice the invention. Notably, the figures and examples below are not meant to limit the scope of the present invention to a single embodiment, but other embodiments are possible by way of interchange of some or all of the described or illustrated elements.
Moreover, where certain elements of the present invention can be partially or fully implemented using known components, only those portions of such known components that are necessary for an understanding of the present invention will be described, and detailed descriptions of other portions of such known components will be omitted so as not to obscure the invention. In the present specification, an embodiment showing a singular component should not be considered limiting; rather, the invention is intended to encompass other embodiments including a plurality of the same component, and vice-versa, unless explicitly stated otherwise herein.
Moreover, applicant does not intend for any term in the specification or claims to be ascribed an uncommon or special meaning unless explicitly set forth as such. Further, the present invention encompasses present and future known equivalents to the known components referred to herein by way of illustration.
Referring now in detail to the drawings the reference numeral 10 denoted a secure dual mount cover for outdoor electrical devices constructed in accordance with the invention including a substantially rectangular base 12 , having a rear panel 14 . A top panel 16 , a right side panel 18 , a left side panel 20 and a bottom panel 22 extend along planes generally perpendicular to the plane of the rear panel 14 . A peripheral flange 24 surrounds the proximal edges of the panels 16 , 18 , 20 and 22 . With reference to FIGS. 5, 6, 8 and 9 , it should be noted that the flange 24 includes an outer bead or rib 25 and an inner bead or rib 27 which define a channel 29 therebetween. The base 12 is preferably molded in one piece of a suitable thermoplastic or other durable material.
A weatherproof lid 26 may be hinged to either the top panel 16 , for orientation of the dual mount cover 10 in a vertical position, or the right side panel 18 , for orientation of the dual mount cover in a horizontal position. Throughout the drawing figures, the dual mount cover 10 is illustrated as being a vertical position with the lid 26 hinged to the top panel 16 , for covering an electrical device mounted within an electrical box in a vertical orientation, except, however, in FIG. 7 , wherein the dual mount cover 10 is illustrated in a horizontal position, for covering an electrical device mounted within an electrical box in a horizontal orientation. The lid 26 is also preferably molded in one piece of a suitable thermoplastic or other durable material.
With attention directed to FIGS. 2 and 3 , it should be noted that the rear panel 14 includes an orifice 28 of generally rectangular shape surrounded by a peripheral recess 30 formed on the inner or front face of the rear panel 14 .
The dual mount cover 10 includes a plurality of adapter plates 32 , 34 and 36 , each of which is dimensioned to be received within the orifice 28 . From an examination of FIG. 3 , it will be noted that each of the adapter plates includes a peripheral flange of reduced thickness 38 , 40 , 42 which is dimensioned to seat in the peripheral recess 30 .
The adapter plates 34 , 36 include openings configured to cover and permit access to the face of a duplex receptacle and devices having rectangular faces including GFCI receptacles respectively. A variety of mounting holes extend through each adapter plate, with the mounting holes configured to receive selected mounting screws for securing the entire cover comprising the assembled cover 10 to an electrical box carrying the electrical device to be covered.
Pursuant to the invention, the adapter plate 32 includes an opening 44 configured to receive on its rear face at least one of a plurality of inserts 46 , 48 , 50 , 52 , 54 for effecting a change in the dimensions of the opening such that the opening size selected will accommodate the face of an electrical device being installed. It should be noted that for convenience of illustration only, FIGS. 2 and 3 illustrate the inserts 52 and 54 in front of the adapter plate 32 , whereas if selected, they are to be inserted at the rear face of the adapter plate 32 .
The adapter plate opening 44 is defined by an inwardly tapered chamfered wall 56 , best illustrated in FIGS. 3 and 5 . A frustum insert 46 or 52 , having a matingly tapered external surface 58 , 60 and a chamfered wall opening may be seated in the adapter plate opening 44 . Successive frustum inserts 48 , 54 , each having a smaller chamfered wall opening, may be inserted within a rear face the opening 62 , 64 of the previously seated insert ( 46 , 52 , respectively). The opening in the adapter plate 32 and the openings of the frustum inserts 46 , 48 , 50 , 52 , 54 are dimensioned to receive the face of a different electrical device. The frustum insert 50 comprises a plug having a rectangular toggle switch opening and may be seated the opening of the frustum insert 48 .
While the frustum inserts, 46 , 48 , 52 , and 54 , by way of example only, comprise frustoconical rings, it should be appreciated that pyramidical or oval frustum inserts could be employed with noncircular and/or circular openings configured to accept the faces of electrical devices having corresponding shapes and/or other successively smaller frustum inserts.
Each of the frustum inserts includes a pair of radially extending diametrically opposed registration tabs 66 configured for placement within in correspondingly dimensioned recessed seats 68 formed in the rear face of the adapter plate 32 , as well as the rear faces of the frustum inserts 46 , 48 , 52 and 54 . There is also provided a notch 70 in each tab 66 and a post 72 , projecting from each seat fits within the notch to secure the frustum insert against rotation or dislodgement from its opening within which it is received prior to complete assembly of the cover.
When configured in the orientation of FIGS. 1-6 , an integral electric cord knock out panel 74 at the bottom of the lid 26 is removed to provide an in use passageway, illustrated in FIG. 6 , while when the lid is hinged about the right side edge, with the hinge being horizontally oriented at the top of the electric box, as illustrated in FIG. 7 , a knock out panel 76 is removed.
The lid 26 is maintained in a closed position by an integral latch 78 , best illustrated in FIG. 6 , having a flange 80 , which engages a keeper surface on the rear face of the base peripheral flange 24 . To release the latch 78 and open the lid, a grip 82 is pulled forwardly.
Both the top and right side of the base 12 include integral arrays of hinge pins and the top and left side panels of the lid 26 include mating arrays of hinge knuckles. The lid 26 is mounted to either array of pins, depending upon the orientation of the electric box base the device, such that the lid 26 is hinged in a generally horizontal plane adjacent the top of the electric box. One or more pins of each array is longer than its respective knuckle, is slotted and has a mushroomed head to prevent inadvertent hinge separation.
As shown in FIG. 7 , wherein the hinge pins associated with the top panel 16 are illustrated, a platform 84 which is integral with the base 12 includes a plurality of pin flanges 86 , 88 , 90 and 92 . Each of the pin flanges includes an integral pin 94 , 96 , 98 and 100 , all of which are coaxial. One or more hinge pins 94 , 100 , are longer than the remaining pins, include mushroomed heads and are axially slotted to enable compression of the mushroomed heads. An identical orthogonal array of hinge pins 102 , 104 , 106 , and 108 are formed on the right side panel 18 , with the slots being best illustrated in FIG. 4 .
An array of hinge knuckles 110 , 112 , 114 and 116 , which are configured to mate with the top panel hinge pin arm, is formed integral with the peripheral flange of the lid 26 while an array of hinge knuckles 118 , 120 , 122 and 124 , configured to mate with the orthogonal right side panel hinge pin array, is also formed integral with the peripheral flange of the lid 26 . The lid 26 is mounted to the base 12 by registering the bores of a selected knuckle array with the hinge pins of the selected hinge pin array and sliding the knuckles over the hinge pins, compressing the mushroom heads. When the knuckles are fully seated over the pins and the knuckles abut their respective hinge flanges, the mushroom heads extend beyond their knuckles and expand to prevent inadvertent disengagement.
It should be noted that a pair of haspways 126 , 128 are formed through opposed diagonal corners of the base peripheral flange 24 . When the lid is closed, a lowermost one of the haspways 126 or 128 will be in registration with an aperture 130 formed in a corner of the lid peripheral flange so as to permit the lid to be locked by way of a padlock, wire seal, etc.
In accordance with the invention, the base 12 is molded in one piece with the haspway 126 closed by an integral web 127 (illustrated in FIG. 7 ) and the haspway 128 closed by an integral web 129 (illustrated in FIGS. 8 and 10 ). The thickness of the webs 127 , 129 is reduced, at least around their peripheral junctions with the haspways 126 , 128 respectively, in order to facilitate removal by being broken away, knocked out or punched out with a suitable tool, e.g., a screwdriver, drift pin, or other implement which is dimensioned for insertion through the haspway.
If the cover is mounted in a vertical position and it is desired to secure the electrical device from unauthorized access, the web 127 is broken away, as illustrated in FIGS. 2, 3 and 8 , for receiving a security member, e.g., a padlock shackle, bolt, wire seal, tie strap or the like through the registered aperture 130 and haspway 126 .
If the cover is mounted in a horizontal position and it is desired to secure the electrical device from unauthorized access, the web 129 is broken away, as illustrated in FIG. 7 , for receiving a security member, e.g., a padlock shackle, bolt, wire seal, tie strap or the like through the registered aperture 130 and haspway 128 .
Thus it will be seen that there is provided a dual mount cover for outdoor electrical devices which achieves the various aspects, features and considerations of the present invention and which is well suited for practical use.
All publications and references cited herein are expressly incorporated herein by reference in their entirety.
In the figures of this application, in some instances, a plurality of elements may be shown as illustrative of a particular element, and a single element may be shown as illustrative of a plurality of a particular elements. Showing a plurality of a particular element is not intended to imply that a system or method implemented in accordance with the invention must comprise more than one of that element or step, nor is it intended by illustrating a single element that the invention is limited to embodiments having only a single one of that respective element. Those skilled in the art will recognize that the numbers of a particular element shown in a drawing can, in at least some instances, be selected to accommodate the particular user needs.
The particular combinations of elements and features in the above-detailed embodiments are exemplary only, the interchanging and substitution of these teachings with other teachings in this and the incorporated-by-reference patents and applications are also expressly contemplated. As those skilled in the art will recognize, variations, modifications, and other implementations of what is described herein can occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed.
Further, in describing the invention and in illustrating embodiments of the invention in the figures, specific terminology, numbers, dimensions, materials, etc. are used for the sake of clarity. However the invention is not limited to the specific terms, numbers, dimensions, materials, etc. so selected, and each specific term, number, dimension, material, etc., at least includes all technical and functional equivalents that operate in a similar manner to accomplish a similar purpose. Use of a given word, phrase, number, dimension, material, language terminology, product brand, etc. is intended to include all grammatical, literal, scientific, technical, and functional equivalents. The terminology used herein is for the purpose of description and not limitation.
Having described the preferred embodiments of the invention, it will now become apparent to one of ordinary skill in the art that other embodiments incorporating their concepts may be used. Moreover, those of ordinary skill in the art will appreciate that the embodiments of the invention described herein can be modified to accommodate and/or comply with changes and improvements in the applicable technology and standards referred to herein. For example, the technology can be implemented in many other, different, forms, and in many different environments, and the technology disclosed herein can be used in combination with other technologies. Variations, modifications, and other implementations of what is described herein can occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. It is felt therefore that these embodiments should not be limited to disclosed embodiments but rather should be limited only by the spirit and scope of the appended claims.
The particular combinations of elements and features in the above-detailed embodiments are exemplary only; the interchanging and substitution of these teachings with other teachings in this and the referenced patents/applications are also expressly contemplated. As those skilled in the art will recognize, variations, modifications, and other implementations of what is described herein can occur to those of ordinary skill in the art without departing from the spirit and the scope of the invention as claimed. Accordingly, the foregoing description is by way of example only and is not intended as limiting. The invention's scope is defined in the following claims and the equivalents thereto.
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A cover for outdoor electrical devices includes a rectangular base having a rear, side and bottom panels. A peripheral flange surrounds the base. Haspways are provided in diagonally opposed corners of the flange, with the haspways being closed by a web. A lid is hinged to the top panel, for orientation in a vertical position or to a side panel for orientation in a horizontal position. An aperture at a lower corner of the lid registers with a lower haspway. To secure the cover, the lower haspway web is broken and padlock shackle inserted through the open haspway and lid aperture. The haspway at the upper corner of the base flange remains closed by the web to preclude the entrance of water into the interior of the cover.
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CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority of Korean Patent Application Number 10-2012-0111405 filed Oct. 8, 2012, the entire contents of which application is incorporated herein for all purposes by this reference.
BACKGROUND OF INVENTION
[0002] 1. Field of Invention
[0003] The present invention relates to a hydraulic pressure supply system of an automatic transmission for a vehicle. More particularly, the present invention relates to a hydraulic pressure supply system of an automatic transmission for a vehicle which prevents power loss by variably controlling discharging flow amount of a high-pressure hydraulic pump in the hydraulic pressure supply system having a low-pressure hydraulic pump and the high-pressure hydraulic pump driven by one drive shaft.
[0004] 2. Description of Related Art
[0005] Recently, vehicle makers direct all their strength to improve fuel economy due to worldwide high oil prices and strengthen of exhaust gas regulations.
[0006] Improvement of fuel economy may be achieved by improving power delivery efficiency in an automatic transmission, and improvement of the power delivery efficiency may be achieved by minimizing unnecessary power consumption of a hydraulic pump.
[0007] A recent automatic transmission is provided with a low-pressure hydraulic pump and a high-pressure hydraulic pump so as to improve fuel economy. Therefore, hydraulic pressure generated by the low-pressure hydraulic pump is supplied to a low pressure portion (i.e., a torque converter, a cooling device, and a lubrication device), and hydraulic pressure generated by the high-pressure hydraulic pump is supplied to a high pressure portion (i.e., friction members selectively operated when shifting).
[0008] In further detail, general hydraulic pressure of the automatic transmission is generated for the low pressure portion (i.e., generated by the low-pressure hydraulic pump), and hydraulic pressure demanded by the high pressure portion is generated by the high-pressure hydraulic pump and then is supplied to the high pressure portion.
[0009] Since power consumption for driving the hydraulic pumps can be minimized, fuel economy may be enhanced. In addition, since a load applied to the hydraulic pumps is reduced, noise and vibration may be reduced and durability may be improved.
[0010] According to such an oil supply system, the low-pressure hydraulic pump and the high-pressure hydraulic pump are driven by one drive shaft. In this case, since rotation speeds of the low-pressure hydraulic pump and the high-pressure hydraulic pump cannot be independently controlled, oil amount larger than necessary oil amount may be supplied from the high-pressure hydraulic pump.
[0011] If the oil amount larger than necessary oil amount is supplied from the high-pressure hydraulic pump, the high hydraulic pressure higher than necessary hydraulic pressure may be generated. In addition, driving torque for driving the high-pressure hydraulic pump may be unnecessarily consumed so as to generate the high hydraulic pressure higher than the necessary hydraulic pressure.
[0012] The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
SUMMARY OF INVENTION
[0013] Various aspects of the present invention provide for a hydraulic pressure supply system of an automatic transmission for a vehicle having advantages of minimizing loss of power for driving a high-pressure hydraulic pump by variably controlling oil amount so as for a high-pressure hydraulic pump to generate necessary hydraulic pressure in the hydraulic pressure supply system having a low-pressure hydraulic pump and the high-pressure hydraulic pump driven by one drive shaft.
[0014] A hydraulic pressure supply system of an automatic transmission for a vehicle according to various aspects of the present invention is adapted to generate low hydraulic pressure and high hydraulic pressure using oil stored in an oil pan and supply the low hydraulic pressure and the high hydraulic pressure respectively to a low pressure portion and a high pressure portion.
[0015] The hydraulic pressure supply system may include: a low-pressure hydraulic pump pumping the oil stored in the oil pan and generating the low hydraulic pressure; a low-pressure regulator valve controlling the low hydraulic pressure supplied from the low-pressure hydraulic pump to be stable hydraulic pressure, and supplying the stable hydraulic pressure to the low pressure portion; a high-pressure hydraulic pump changing the low hydraulic pressure supplied from the low-pressure hydraulic pump into the high hydraulic pressure and supplying the high hydraulic pressure to the high pressure portion; and a high-pressure regulator valve controlling the high hydraulic pressure supplied from the high-pressure hydraulic pump to the high pressure portion to be stable hydraulic pressure, wherein the low-pressure hydraulic pump and the high-pressure hydraulic pump are driven by one drive shaft, and the high-pressure hydraulic pump is a variable capacity hydraulic pump capable of controlling discharging flow amount according to driving condition.
[0016] The high-pressure hydraulic pump may be a variable capacity vane pump.
[0017] The high-pressure hydraulic pump may be controlled by control pressure of a solenoid valve controlling the high-pressure regulator valve.
[0018] The solenoid valve may be a proportional control solenoid valve.
[0019] The variable capacity vane pump may include: a housing including an input port receiving the oil, an output port discharging the oil supplied to the input port, and a rotor chamber fluidly communicated with the input port and the output port; pumping means including an annular outer rotor disposed in the rotor chamber of the housing and having a load input end at a side of an exterior circumference thereof, an inner rotor disposed in and eccentric to the outer rotor and connected to the drive shaft, and a plurality of vanes inserted in an exterior circumference of the inner rotor so as to be slidable radially; and variable capacity control means disposed at a side portion of the housing and changing pump volume by controlling eccentric amount of the outer rotor according to the control pressure of the solenoid valve controlling the high-pressure regulator valve.
[0020] The variable capacity control means may include: a valve body having an inflow port formed at a side portion thereof and receiving the control pressure of the solenoid valve and an exhaust port formed at the other side portion thereof; a valve spool slidably mounted in the valve body and having a land and an operating rod protruded at the side surface of the land by a predetermined length and contacting with the load input end of the outer rotor; and an elastic member disposed between the other side surface of the land and the valve body.
[0021] The valve body may be integrally formed with the housing.
[0022] The valve body may be formed separately from the housing and may be mounted in the housing.
[0023] The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a schematic diagram of an exemplary hydraulic pressure supply system according to the present invention.
[0025] FIG. 2 is a schematic diagram of an exemplary hydraulic pump used in a hydraulic pressure supply system according to the present invention.
[0026] FIG. 3 is a schematic diagram of an exemplary high-pressure hydraulic pump used in a hydraulic pressure supply system according to the present invention.
[0027] FIG. 4 is a cross-sectional view of variable capacity control means of an exemplary high-pressure hydraulic pump used in a hydraulic pressure supply system according to the present invention.
DETAILED DESCRIPTION
[0028] Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.
[0029] Description of components that are not necessary for explaining the present exemplary embodiment will be omitted, and the same constituent elements are denoted by the same reference numerals in this specification.
[0030] In the detailed description, ordinal numbers are used for distinguishing constituent elements having the same terms, and have no specific meanings.
[0031] FIG. 1 is a schematic diagram of a hydraulic pressure supply system according to various embodiments of the present invention.
[0032] Referring to FIG. 1 , a hydraulic pressure supply system according to various embodiments of the present invention is adapted to supply low hydraulic pressure generated by a low-pressure hydraulic pump 2 to a low pressure portion 4 such as a torque converter (T/C), a cooling portion, a lubrication portion and to supply high hydraulic pressure generated by a high-pressure hydraulic pump 6 to a high pressure portion 8 for operating friction members related to shifting.
[0033] The low hydraulic pressure is a lower pressure facilitating operation of the torque converter (T/C) and cooling and lubrication, and the high hydraulic pressure is a high pressure facilitating operation of a plurality of friction members.
[0034] The hydraulic pressure generated by the low-pressure hydraulic pump 2 is controlled to a stable hydraulic pressure by a low-pressure regulator valve 10 and is then supplied to the low pressure portion 4 .
[0035] The low-pressure hydraulic pump 2 receives oil stored in an oil pan P through a first input line 12 and discharges the low hydraulic pressure to a first low-pressure line 14 .
[0036] In addition, the low-pressure regulator valve 10 is connected to the first low-pressure line 14 and is connected to the first input line 12 through a first recirculation line 16 .
[0037] Therefore, the low-pressure regulator valve 10 recirculates a portion of the hydraulic pressure supplied through the first low-pressure line 14 to the first input line 12 through the first recirculation line 16 so as to control the hydraulic pressure.
[0038] For this purpose, the low-pressure regulator valve 12 may be a spool valve and is controlled by elastic force of an elastic member 18 disposed at a side portion thereof and the hydraulic pressure of the first low-pressure line 14 supplied to the opposite side of the elastic member 18 so as to control opening area of the first recirculation line 16 . Therefore, the hydraulic pressure supplied to the low pressure portion 4 can be controlled.
[0039] The hydraulic pressure generated by the high-pressure hydraulic pump 6 is controlled to be stable hydraulic pressure by a high-pressure regulator valve 20 and is then supplied to the high pressure portion 8 .
[0040] The high-pressure hydraulic pump 6 changes the low hydraulic pressure supplied from the low-pressure hydraulic pump 2 into the high hydraulic pressure, and supplies the high hydraulic pressure to the high pressure portion 8 through a high-pressure line 22 .
[0041] The high-pressure regulator valve 20 is connected to the high-pressure line 22 and is connected to the first low-pressure line 14 through a second recirculation line 24 . Therefore, the high-pressure regulator valve 20 recirculates a portion of the hydraulic pressure supplied through the high-pressure line 22 to the first low-pressure line 14 through the second recirculation line 24 so as to control the hydraulic pressure.
[0042] For this purpose, the high-pressure regulator valve 20 may be a typical spool valve. In addition, the high-pressure regulator valve 20 is adapted to be controlled by control pressure of a solenoid valve SOL capable of performing proportional control, elastic force of an elastic member 26 , and the hydraulic pressure of the high-pressure line 22 counteracting the control pressure of the solenoid valve SOL. The elastic force of the elastic member 26 is set according to the hydraulic pressure demanded by the high-pressure line 22 .
[0043] As described above, the low hydraulic pressure generated by the low-pressure hydraulic pump 2 is supplied to the low pressure portion 4 , and the high hydraulic pressure generated by the high-pressure hydraulic pump 6 is supplied to the high pressure portion 8 .
[0044] The low-pressure hydraulic pump 2 and the high-pressure hydraulic pump 6 may be driven by separate power sources, but it is exemplified in various embodiments of the present invention that the low-pressure hydraulic pump 2 and the high-pressure hydraulic pump 6 are driven by one drive shaft.
[0045] FIG. 2 is a schematic diagram of a hydraulic pump used in a hydraulic pressure supply system according to various embodiments of the present invention.
[0046] Referring to FIG. 2 , the low-pressure hydraulic pump 2 and the high-pressure hydraulic pump 6 are driven by one power source 30 and the one drive shaft 32 . The power source 30 may be an engine or a motor. If the power source 30 rotates the drive shaft 32 , the low-pressure hydraulic pump 2 and the high-pressure hydraulic pump 6 disposed on the drive shaft 32 rotate to the same direction and generate the hydraulic pressure.
[0047] The low-pressure hydraulic pump 2 is connected to the first input line 12 through a first input hole 34 so as to receive the oil from the oil pan P, and is connected to the first low-pressure line 14 through a first output hole 36 so as to supply the low hydraulic pressure to the low pressure portion 4 .
[0048] The high-pressure hydraulic pump 6 includes a second input hole 38 , and the second input hole 38 is connected to the first output hole 36 through a connecting line 40 such that the high-pressure hydraulic pump 6 receives the hydraulic pressure generated by the low-pressure hydraulic pump 2 . In addition, the high-pressure hydraulic pump 6 is connected to the high-pressure line 22 through a second output hole 42 so as to supply the high hydraulic pressure to the high pressure portion 8 .
[0049] The connecting line 40 is included in the first low-pressure line 14 shown in FIG. 1 and the second input hole 38 is connected to the second recirculation line 24 .
[0050] In addition, the high-pressure hydraulic pump 6 is a variable capacity vane pump according to various embodiments of the present invention.
[0051] FIG. 3 is a schematic diagram of a high-pressure hydraulic pump used in a hydraulic pressure supply system according to various embodiments of the present invention.
[0052] Referring to FIG. 3 , the high-pressure hydraulic pump 6 is the variable capacity vane pump and the variable capacity vane pump includes a housing 100 , pumping means 200 , and variable capacity control means 300 .
[0053] The housing 100 includes an input port 102 receiving the oil and an output port 104 discharging the oil supplied to the input port 102 . In addition, the housing 100 further includes a rotor chamber 106 connected to the input port 102 so as to receive the oil and connected to the output port 104 so as to discharge the oil.
[0054] The pumping means 200 include an outer rotor 202 , an inner rotor 204 , and a plurality of vanes 206 .
[0055] The outer rotor 202 has an annular shape and is disposed in the rotor chamber 106 of the housing 100 . A load input end 208 is formed at a side of an exterior circumference of the outer rotor 202 .
[0056] The inner rotor 204 is disposed in and is eccentric to the outer rotor 202 and is connected to the drive shaft 32 .
[0057] The plurality of vanes 206 is inserted in an exterior circumference of the inner rotor 204 so as to be slidable radially, and is disposed circumferentially with even distances.
[0058] Therefore, if the inner rotor 204 rotates, the vane 206 is pushed radially outwardly and a free end of the vane contacts with an interior circumference of the outer rotor 202 .
[0059] The pumping means 200 pressurizes the oil supplied to the rotor chamber 106 when the inner rotor 204 is rotated by the drive shaft 32 , and feeds the pressurized oil to the output port 104 .
[0060] The variable capacity control means 300 is disposed in a receiving chamber 108 formed at a side portion of the housing 100 , and controls eccentric amount of the outer rotor 202 according to driving condition so as to control pump volume.
[0061] FIG. 4 is a cross-sectional view of variable capacity control means of a high-pressure hydraulic pump used in a hydraulic pressure supply system according to various embodiments of the present invention.
[0062] The variable capacity control means 300 includes a valve body 310 and a valve spool 320 .
[0063] The valve body 310 may be monolithically formed with the housing 100 or may be formed separately from the housing and is mounted in the receiving chamber 108 .
[0064] The valve body 310 includes an inflow port 312 formed at a side portion thereof and receiving the control pressure of the solenoid valve SOL and an exhaust port EX formed at the other side portion thereof.
[0065] The valve spool 320 slidably mounted in the valve body 310 includes one land 322 and an operating rod 324 protruded from a side surface of the land 322 by a predetermined length and contacting with the load input end 208 of the outer rotor 202 .
[0066] An elastic member 326 is disposed at the other side surface of the land 322 and the valve body 310 .
[0067] Therefore, the control pressure supplied into the inflow port 312 is applied to the side surface of the land 322 of the valve spool 320 and elastic force of the elastic member 326 is applied to the other side surface of the land 322 . Therefore, the valve spool 320 moves to the left or to the right in the drawing by the control pressure and the elastic force.
[0068] The elastic member 326 is disposed between the land 322 of the valve spool 320 and an adjust bolt 328 , and pushes the valve spool 320 to the right in the drawing so as for the operating rod 324 to contact with the load input end 208 at an initial operating state.
[0069] In addition, the elastic force of the elastic member 326 may be set according to the control pressure supplied into the inflow port 312 by a person of an ordinary skill in the art.
[0070] Discharging flow amount of the high-pressure hydraulic pump 6 is determined according to the control pressure of the solenoid valve SOL supplied into the inflow port 312 of the variable capacity control means 300 .
[0071] That is, if the control pressure of the solenoid valve SOL is not supplied, the valve spool 320 is pushed to the right in the drawings by the elastic force of the elastic member 326 and eccentric amount of the outer rotor 202 increases, as shown in FIG. 3 and FIG. 4 . Therefore, the discharging flow amount of the high-pressure hydraulic pump 6 is increased.
[0072] On the contrary, if the control pressure of the solenoid valve SOL is supplied, the control pressure of the solenoid valve SOL wins against the elastic force and the valve spool 320 is moved to the left in the drawings. Therefore, the eccentric amount of the outer rotor 202 is reduced and the discharging flow amount of the high-pressure hydraulic pump 6 is also reduced.
[0073] Since the high-pressure hydraulic pump 6 is the variable capacity vane pump and the discharging flow amount of the variable capacity vane pump is variably controlled by the control pressure of the solenoid valve SOL controlling the hydraulic pressure of high pressure portion 8 , generation of the hydraulic pressure that is unnecessarily high is prevented according to various embodiments of the present invention.
[0074] In addition, since generation of unnecessary hydraulic pressure is prevented, driving torque for driving the high-pressure hydraulic pump 6 may be minimized and power loss may be reduced.
[0075] For convenience in explanation and accurate definition in the appended claims, the terms lower and etc. are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.
[0076] The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.
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A hydraulic pressure supply system of an automatic transmission generates low and high hydraulic pressures using oil stored in an oil pan and supplies the low and high hydraulic pressures respectively to a low and a high pressure portions. The system may include: a low-pressure hydraulic pump pumping the oil stored in the oil pan; a low-pressure regulator valve controlling the low hydraulic pressure to be stable hydraulic pressure, and supplying the stable hydraulic pressure to the low pressure portion; a high-pressure hydraulic pump changing the low hydraulic pressure into the high hydraulic pressure and supplying it to the high pressure portion; and a high-pressure regulator valve controlling the high hydraulic pressure to be stable hydraulic pressure, wherein the low-pressure and high-pressure hydraulic pumps are driven by one drive shaft, and the high-pressure hydraulic pump is a variable capacity hydraulic pump capable of controlling discharging flow amount.
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BACKGROUND OF THE INVENTION
This invention relates to novel derivatives of 1,5-dideoxy-1,5-imino-D-glucitol having amino or azido substituents at C-2 and/or C-3, and, more particularly, to the chemical synthesis of these derivatives and intermediates therefor, and to their method of inhibiting viruses such as lentiviruses.
1,5-dideoxy-1,5-imino-D-glucitol (deoxynojirimycin or DNJ) and its N-alkyl and O-acylated derivatives are known inhibitors of viruses such as human immunodeficiency virus (HIV). See, e.g., U.S. Pat. Nos. 4,849,430; 5,003,072; 5,030,638 and PCT Int'l. Appln. WO 87/03903. Several of these derivatives also are effective against other viruses such as HSV and CMV as disclosed in U.S. Pat. No. 4,957,926. In some cases antiviral activity is enhanced by combination of the DNJ derivative with other antiviral agents such as AZT as described in U.S. Pat. No. 5,011,829. Various of these DNJ derivative compounds are antihyperglycemic agents based on their activity as glycosidase inhibitors. See, e.g., U.S. Pat. Nos. 4,182,763, 4,533,668 and 4,639,436. The 2-acetamide derivatives of DNJ also are reported to be potent glycosidase inhibitors by Fleet et al., Chem. Lett. 7, 1051-1054 (1986); and Kiso et al. J. Carbohydr. Chem. 10, 25-45 (1991).
Notwithstanding the foregoing, the search continues for the discovery and novel synthesis of new and improved antiviral compounds.
BRIEF DESCRIPTION OF THE INVENTION
In accordance with the present invention, novel derivatives of 1,5-dideoxy-1,5-imino-D-glucitol having amino or azido substituents at C-2 and/or C-3 are provided. According to another embodiment of the invention, novel methods of chemical synthesis of these DNJ derivatives and their intermediates are provided. The novel DNJ derivatives and various of their intermediates have useful antiviral activity as demonstrated against lentivirus.
The novel C-2 and/or C-3 amino or azido substituted derivatives of 1,5-dideoxy-1,5-imino-D-glucitol can be represented by the following general structural Formula I: ##STR1## wherein R=H, alkyl, and aralkyl;
X 1 =OH, N 3 , NH 2 , NHR 1 , NR 2 and NHCOR 3 ;
X 2 =OH, N 3 and NH 2 , provided that when X 2 is N 3 or NH 2 , X 1 is OH or NH 2 , and provided further that at least one of X 1 and X 2 is not OH;
R 1 ,R 2 =alkyl; and
R 3 =H, alkyl.
In Formula I, the alkyl moieties in the R, R 1 , R 2 and R 3 substituents preferably are straight chain or branched alkyl groups or cycloalkyl groups which preferably have from one to about 8 carbon atoms in R 1 , R 2 and R 3 , e.g., methyl, ethyl, propyl, isopropyl, n-butyl, iso-butyl, sec.-butyl. tert-butyl, pentyl, hexyl, heptyl, octyl, 2-ethylbutyl, 2-methylpentyl, cyclopentyl and cyclohexyl, and from one to about 18 carbon atoms in R, e.g., dodecyl, octadecyl or any of the above groups.
Also in Formula I, the aryl moieties in the R substituents preferably are phenyl and substituted phenyl, e.g. benzyl, 4,fluorophenyl or 3-methoxyphenyl.
Preferred compounds of Formula I are the following:
2-Azido Derivatives of DNJ
2-Azido-1,2,5-trideoxy-1,5-imino-D-glucitol
2-Azido-1,5-(butylimino)-1,2,5-trideoxy-D-glucitol
2-Azido-1,5-[(2-ethylbutyl)imino]-1,2,5-trideoxy-D-glucitol
2-Azido-1,5-[(4,4,4-trifluorobutyl)imino]-1,3,5-trideoxy-D-glucitol
2-Amino Derivatives of DNJ
2-Amino-1,2,5-trideoxy-1,5-imino-D-glucitol
2-Amino-1,5-(butylimino)-1,2,5-trideoxy-D-glucitol
2-Amino-1,5-[(2-ethylbutyl)imino]-1,2,5-trideoxy-D-glucitol
2-Amino-1,5-[(4,4,4-trifluorobutyl)imino]-1,2,5-trideoxy-D-glucitol
1,5-(Butylimino)-1,2,5-trideoxy-2-(dimethylimino)-D-glucitol
1,5-(Butylimino)-1,2,5-trideoxy-2-(methylamino)-D-glucitol
1,5(Butylimino)-1,2,5-trideoxy-2-[(1-oxobutyl)amino]-D-glucitol
1,5(Butylimino)-1,2,5-trideoxy-2-[(1-oxobutyl)amino]-D-glucitol, tributanoate
3-Amino Derivatives of DNJ
3-Amino-1,3,5-trideoxy-1,5-imino-D-glucitol
2,3-Diamino-1,5-(butylimino)-1,2,3,5-tetradeoxy-D-glucitol
The novel synthesis of compounds of Formula I comprises the formation of structural modifications at C2 and C3 of DNJ and the nucleophilic opening of N-carboalkoxy-2,3-anhydro-DNJ.
In accordance with a preferred embodiment of the invention, the compounds of Formula I can be chemically synthesized by the sequence of reactions shown in the following generic Reaction Schemes A, D and F in which the Roman numerals in parentheses refer to the compounds defined by the generic formula shown above said numbers. R 1 can be any alkyl or aryl group such as illustrated by the reactants and products described hereinafter. ##STR2##
The foregoing Reaction Scheme A comprises the following general reaction steps:
(a) The starting material, DNJ (I), is N-acylated with an acylating agent to form a carbamate derivative of DNJ (II);
(b) The hydroxyls at C-4 and C-6 are protected with a hydroxyl protecting agent by acetalization or ketalization to form an acetal or ketal (III);
(c) The hydroxyl at C-2 is protected by regioselective sulfonylation with a sulfonylating agent at C-2 to give the 2-sulfonated intermediate (IV);
(d) A 2,3-anhydro derivative is formed by epoxidation at C-2 and C-3 to give the epoxide intermediate (V);
Epoxide intermediate (V) is used for synthesis of 2-azido and 2-amino derivatives of DNJ in the following steps of Reaction Scheme A or retained for synthesis of 3-amino derivatives of 1,5-imino-D-altritol in Reaction Scheme H.
(e) The epoxide intermediate (V) is opened by nucleophilic attack at C-2 and C-3 such as with an azide to give a mixture of azido derivatives (VI) and (VII);
Azido derivative (VII) is retained for synthesis of 3-azido and 3-amino derivatives of DNJ in Reaction Scheme D.
Azido derivative (VI) is used for synthesis of 2-azido and 2-amino derivatives of DNJ in the following steps of Reaction Scheme A or retained for synthesis of 2,3-diamino derivatives of DNJ in Reaction Scheme F.
(f) The N-carbamate group in azido derivative (VI) is removed to give intermediate (VIII).
(g) Intermediate (VIII) is N-alkylated to give the divergent intermediate (IX) which can be used to prepare the final 2-azido or 2-amino derivatives of DNJ.
(h) The hydroxyl protecting group at C-4 and C-6 of intermediate (IX) is removed by cleavage of acetal or ketal to give the desired novel antiviral 2-azido derivatives of DNJ (X),
(i) The 2-azido group in intermediate (IX) is reduced to the 2-amino group to give intermediate (XI);
(j) The hydroxyl protecting group at C-4 and C-6 of intermediate (XI) is removed by cleavage of acetal or ketal to give the desired novel antiviral 2-amino derivatives of DNJ (XII).
N-Acylation of DNJ I) in step (a) can be carried out by conventional N-acylation procedures well known to those skilled in the art. Suitable general procedures for acylation of amines are described in U.S. Pat. No. 5,003,072; March, J. in Advanced Organic Chemistry, Wiley, N.Y., 1985; Patai, S. (Ed.) in The Chemistry of Amides, Wiley, N.Y., 1970. For example, DNJ is N-acylated to form carbamate or thiocarbamate using a variety of reagents such as chloroformates (e.g., methyl chloroformate, ethyl chloroformate, vinyl chloroformate, benzyl chloroformate) or dicarbonates (e.g., di-tert-butyl dicarbonate). The reaction of DNJ (I) with anhydrides, chloroformates or dicarbonates is preferentially carried out by dissolving in one or more of polar, protic solvents (such as water, methanol, ethanol) and in the presence of a base (e.g, potassium carbonate, lithium carbonate, sodium carbonate, cesium carbonate, triethylamine, pyridine, 4-dimethylaminopyridine, diisopropylethylamine, 1,8-diazabicyclo[5,4,0]undec-7-ene). N-Acylation is preferentially carried out by reacting DNJ (I) with alkyl or aryl chloroformate in solvents such as DMF or aqueous sodium bicarbonate at 20°-50° C. to give the product (II).
Protection of the hydroxyl groups at C-4 and C-6 in step (b) to give acetal or ketal derivative (III) can be carried out by conventional hydroxyl protection procedures such as those described, e.g., in U.S. Pat. No. 5,003,072 and in Green, T. W., Protective Groups in Organic Synthesis, Wiley, N.Y., 1991. The cyclic acetals and ketals are formed by the reaction of 4,6-dihydroxy compound (II) with an aldehyde or a ketone in the presence of an acid catalyst. Illustrative carbonyl (or carbonyl equivalents such as dimethyl acetal or dimethyl ketal) compounds useful in this reaction are acetone, acetaldehyde, methyl phenyl ketone, benzaldehyde, 4-methoxybenzaldehyde, 2,4-dimethoxybenzaldehyde, 4-dimethylaminobenzaldehyde, 2-nitrobenzaldehyde, 2,2,2-trichloroacetaldehyde (chloral) and acetophenone. The acid catalysts suitable for this reaction are, e.g., para-toluene sulfonic acid, cat. HCl, cat. sulfuric acid, FeCl 3 , ZnCl 2 , SnCl 2 and BF 3 -ether, and the reaction is carried out in the presence of aprotic solvents such as methylene chloride, 1,2-dimethoxyethane, dioxane, dimethylformamide, dimethylacetamide or dimethylsulfoxide. Thus para-toluene sulfonic acid is added to a solution of benzaldehyde dimethyl acetal in organic medium, e.g., dimethylformamide, and reacted with N-acyl-DNJ (II) at 20°-65° C. to give the product (III).
The selective protection of the hydroxy group at C-2 in compound (III) ,in step (c) can be carried out by regioselective sulfonylation to give the sulfonate (IV). For example, compound (III) is conveniently refluxed with dibutyltinoxide in solvents (such as benzene, toluene, xylene, methanol or ethanol and the like) to form a homogeneous solution. The stannylene intermediate is then reacted with p-toluenesulfonyl chloride to give tosylate (IV). Other sulfonyl chlorides such as benzenesulfonyl chloride, 4-bromobenzenesulfonyl chloride, 4-nitrobenzenesulfonyl chloride and methanesulfonyl chloride can also be used in this reaction.
The epoxide intermediate (V) is readily prepared in step (d) by treatment of the sulfonate (IV) with base such as sodium hydride, potassium hydride, lithium hydride, cesium carbonate, potassium carbonate and potassium tert-butoxide using solvents such as dimethylformamide, dimethylacetamide, dimethylsulfoxide, dimethoxyethane, tetrahydrofuran, dioxane, diethyl ether, dibutyl ether and tert-butyl methyl ether.
The nucleophilic opening of epoxide intermediate (V) in step (e) is preferably carried out by heating (50° C.-reflux) a solution of (V) in solvents such as dimethylformamide, dimethylacetamide, 2-methoxyethanol, dimethoxyethane, tetrahydrofuran, dioxane, dibutl ether and tert-butyl methyl ether with sodium azide to give diasteromeric mixture of the products (VI) and (VII).
The nitrogen protecting carbamate group in compound (VI) can be easily removed in step (f) by base hydrolysis at temperature of 40° to 100° C. to give the intermediate (VIII). Illustrative bases suitable for this reaction are aqueous sodium hydroxide, lithium hydroxide or potassium hydroxide with or without the presence of organic solvents such as methanol, ethanol, ethylene glycol and dioxane. The carbamates can also be cleaved by other reagents such as sulfur nucleophiles (e.g., sodium thiomethoxide and lithium thiopropoxide) or iodotrimethylsilane.
N-Alkylation of intermediate (VIII) can be carried out in step (g) by reductive alkylation procedures using NaCNBH 3 , NaBH 4 or alkylaldehyde. Appropriate alkylaldehydes for preparing the corresponding N-alkyl derivative compounds (IX) are, e.g., n-propanal, n-butanal, n-pentanal, n-hexanal, n-heptanal and n-octanal. Preferred aldehydes for this reaction are, e.g., butyraldehyde, 3-phenylpropionaldehyde and 2-ethylbutyraldehyde.
Alternatively, N-alkylation can be achieved by reacting intermediate (VIII) with alkylhalide such as benzyl bromide, bromobutane, bromohexane, iodomethane and the like in the presence of a base such as triethylamine, pyridine and diisopropylethylamine. Suitable solvents for the reaction are, e.g., DMF, dimethylacetamide, dimethylsulfoxide and pyridine. A preferred alkylhalide for the N-alkylation is 1-bromo-4,4,4-trifluorobutane.
The acetal or ketal group from the intermediate (IX) can be removed by acid catalyzed hydrolysis in step (h) to give the novel 2-azido derivatives of DNJ (X). Acids can be used such as trifluoacetic acid (with or without water), aqueous hydrochloric acid, boron trichloride, 1N sulfuric acid, 80% acetic acid, with acidic resin (such as Dowex 50-W, H + ), catalytic p-toluenenesulfonic acid in methanol or ethanol at 25°-80° C. The benzylidine acetal can also be cleaved using N-bromosuccinimide and BaCO 3 (or CaCO 3 ) in carbon tetrachloride or by eletrochemical reduction.
Reduction of the 2-azido group in intermediate (IX) to give the 2-amino intermediate (XI) in step (i) is conveniently carried out by hydrogenation with palladium on carbon. The acetal or ketal group can then be removed from intermediate (XI) in step (j) by using conditions similar to those elaborated in step (h) to give the novel 2-amino derivatives (XII) of DNJ. When the 4,6-hydroxy protecting group in (XI) is benzylidine acetal, the group may be removed by transfer hydrogenation conditions (e.g., heating a solution of (XI) in ethanol with Pd(OH) 2 and hydrogen donors such as cyclohexene or 1,4-cyclohexadiene). The benzylidine group in (XI) can similarly be removed by using metals (such as Li, Na or K) and liquid ammonia at -70° to -33° C. to give (XII). The benzylidine acetal can also be cleaved using N-bromosuccinimide and BaCO 3 (or CaCO 3 ) in carbon tetrachloride or by electrochemical reduction. 2,2,2-Trichloroethylidine acetal can also be cleaved by catalytic reduction (H 2 , Raney Ni) using aqueous sodium hydroxide and ethanol.
The following Reaction Schemes B and C show the preferred synthesis of, respectively, the 2-azido and 2-amino derivatives of DNJ (Scheme B) and the 2-alkylamino and 2-acylamino derivatives of DNJ (Scheme C), in which the arabic numerals in parentheses refer to compounds prepared in detailed Examples set forth hereinbelow: ##STR3##
The foregoing Reaction Scheme D, which shows the generic synthesis of the 3-azido- and 3-amino-DNJ derivatives of Formula I, comprises the following general reaction steps, starting with azido derivative (VII) which was prepared in step (e) of Reaction Scheme A:
(a) The free hydroxyl group at C-2 in the starting material, azido derivative (VII), is oxidized to give ketone (XIII);
(b) The ketone (XIII) is reduced with a reducing agent such as, e.g., diisobutylaluminum hydride, sodium borohydride and the like, to give the mixture of epimeric alcohols (XIV) and (XV);
(c) The N-carbamate in alcohol (XIV) is hydrolytically cleaved to give intermediate (XVI);
(d) Intermediate (XVI) is N-alkylated to give divergent intermediate (XVII) which can be used to prepare the final 3-azido or 3-amino derivatives of DNJ;
(e) The hydroxyl protecting group at C-4 and C-6 of intermediate (XVII) is removed by cleavage of acetal or ketal to give the desired 3-azido derivatives of DNJ (XVIII);
(f) The 3-azido group in intermediate (XVII) is reduced to the 3-amino group to give intermediate (XIX);
(g) The hydroxyl protecting group at C-4 and C-6 of intermediate (XIX) is removed by cleavage of acetal or ketal to give the desired 3-amino derivatives of DNJ (XX).
In the foregoing Reaction Scheme D, steps (c) through (g) for the synthesis of the 3-azido and 3-amino derivatives of DNJ can be carried out with similar reagents and conditions in a manner analogous to steps (f) through (j) used for the synthesis of the 2-azido and 2-amino derivatives of DNJ in Reaction Scheme A. In step (a), since the rest of the molecule is fully protected, the oxidation of secondary alcohol in (VII) can be successfully carried out by a variety of oxidizing agents. (see, e.g., March, J. in Advanced Organic Chemistry, Wiley, N.Y., 1985; House, H. O. in Modern Synthetic Reactions, Benzamin Publishing Co., Massachusetts, 1972; Augusting, R. L. in Oxidations--Techniques and Applications in Organic Synthesis, Dekker, N.Y., 1969; W. P. Griffith and S. M. Levy, Aldrichchimica Acta 23, 13 (1990); R. M. Moriarty and O. Prakash J. Org. Chem. 50, 151, 1985; A. Mancuso, D. Swern, Synthesis, 165 (1981); S. Czernecki, C. Georgoulus, C. L. Stevens and K. Vijayakantam, Tetrahedron Lett. 26, 1699 (1985); J. Hersovici, M. J. Egra and K. Antonakis, J. Chem. Soc. Perkin Trans. I, 1967 (1982); E. J. Corey, E. Barrette and P. Margriotis, Tetrahedron Lett. 26, 5855 (1985); H. Tomioka, K. Oshima and H. NoZaki, Tetrahedron Lett. 23, 539 (1982). Some of the reagents suitable for oxidation of the C-2 hydroxyl in compound VII are pyridinium chlorochromate (with or without additives such as sodium acetate, celite, alumina, molecular sieves), pyridinium dichromate, chromium trioxide/pyridine, 2,2'-bipyridinium chloroacromate, cyclic chromate ester (E. J. Corey, E. Barrette and P. Margriotis, Tetrahedron Lett. 26, 5855 (1985), RuCl 2 (PPh 3 ) 3 -tert-BuOOH, silver carbonate on celite, cerium (IV) ammonium nitrate (with or without sodium bromate), tetra-n-propylammonium perruthenate, activated dimethyl sulfoxide reagents (using DMSO and one of the electrophilic reagents such as acetic anhydride, trifluoroacetic anhydride, oxalyl chloride, trifluorosulfonic anhydride, dicyclohexylcarbodiimide). Formation of the novel carbonyl compound (XIII) is preferentially carried out by oxidation of the hydroxyl group at C-2 (VII) with trifluoroacetic anhydride in dimethylsulfoxide (DMSO) using methylene chloride as solvent at -70° to 0° C. followed by treatment with base such as triethylamine or diisopropylethylamine at -70° to 25° C.
The following Reaction Scheme E shows the preferred synthesis of the 3-amino derivatives of DNJ in which the arabic numerals in parentheses refer to compounds prepared in detailed Examples set forth hereinbelow. Table 1, below, sets forth the results obtained in proportions of alcohols (33) and (34) by the reduction of ketone (32) under various reducing conditions.
TABLE 1______________________________________Studies on Stereoselective Reduction of 32 ##STR4## ##STR5## Relative Yield Chem. YieldReducing Agent Conditions (33/34) (33 + 34, %)______________________________________NaBH.sub.4 THF/ 52/48 67 MeOH (4/1), -15°-0° C., 30 minLIBH.sub.3 Me -70° to -20° C., 37/63 20MeLiLiBr + 3 hrBH.sub.3Me.sub.2 SMe.sub.3 Al, t-BuMgCl, 0-5° C., 5 hr 85/15 262,6-dibutyl-4-methyl phenolDIBAL-H -70° C., 4 hr 86/14 86(1M soln. intoluene)______________________________________ ##STR6##
The foregoing Reaction Scheme F, which shows the generic synthesis of the 2,3-diamino-DNJ derivatives of Formula I, comprises the following general reaction steps, starting with azido derivative (VI) which was prepared in step (e) of Reaction Scheme A:
(a) Azido derivative (VI) is subjected to inversion of configuration at C-3 to give the talo intermediate (XXI);
(b) The free hydroxyl at C-3 of intermediate (XXI) is sulfonated to give sulfonic ester (XXII);
(c) Sulfonic ester (XXII) is subjected to azide displacement with inversion to the gluco configuration at C-3 to give diazido intermediate (XXIII);
(d) The N-carbamate in diazido intermediate (XXIII) is hydrolytically cleaved to give intermediate (XXIV);
(e) Intermediate (XXIV) is N-alkylated to give divergent intermediate (XXV) which can be used to prepare the final 2,3-diamino or 2,3-diazido derivatives of DNJ;
(f) The hydroxyl protecting group at C-4 and C-6 of intermediate (XXV) is removed by cleavage of acetal or ketal to give the 2,3-diazido derivatives of DNJ (XXVI);
(g) The 2,3-diazido groups in intermediate (XXV) are reduced to the 2,3-diamino groups to give intermediate (XXVII);
(h) The hydroxyl protecting group at C-4 and C-6 of intermediate (XXVII) is removed by cleavage of acetal or ketal to give the desired 2,3-diamino derivatives of DNJ (XXVIII).
In the foregoing Reaction Scheme F, steps (d) through (h) for the synthesis of the 2,3-diazido and 2,3-diamino derivatives of DNJ can be carried out with similar reagents and conditions in a manner analogous to steps (f) through (j) used for the synthesis of the 2-azido and 2-amino derivatives of DNJ in Reaction Scheme A. Reaction steps (a) through (c) involve displacement of hydroxyl at C-3 by an azide group with net retention of configuration.
The following Reaction Scheme G shows the preferred synthesis of the 2,3-diamino derivatives of DNJ in which the arabic numerals in parenthesis refer to compounds prepared in detailed Examples set forth hereinafter. ##STR7##
The following Reaction Scheme H shows the synthesis of 3-amino derivatives of 1,5-imino-D-altritol from epoxide intermediate (V) of Reaction Scheme A and, preferably, the epoxide intermediate (5) of Reaction Scheme B. Reaction Scheme H comprises the following reaction steps in which the arabic numerals in parentheses refer to compounds prepared in detailed Examples set forth hereinbelow:
(a) The epoxide intermediate (5) is opened by refluxing in alkylamine such as N,N-dimethylaminoethylamine or butylamine to give the C-4 and C-6 hydroxyl protected 3-amino derivatives of 1,5-imino-altritol (47) and (48), respectively;
(b) The benzyl carbamate (Z) on the 3-amino derivative (47) is removed by base hydrolysis or by catalytic hydrogenation procedures (H 2 and Pd/C or H 2 and Pd black) to give intermediate (49); and
(c) The hydroxyl protecting group at C-4 and C-6 of intermediate (49) is removed by cleavage of acetal or ketal to give the desired novel antiviral 3-amino derivative of 1,5-imino-D-altritol (50). This step can be carried out in a manner analogous to the acid catalysed hydrolysis to remove the acetal or ketal group from intermediate (IX) in step (h) of Reaction Scheme A. ##STR8##
In standard in vitro tests, the novel compounds of the invention were demonstrated to have inhibitory activity against visna virus in a conventional plaque reduction assay. Visna virus, a lentivirus genetically very similar to the AIDS virus, is pathogenic for sheep and goats. See Sonigo et al., Cell 42, 369-382 (1985); Haase, Nature 322, 130-136 (1986). Inhibition of visna virus replication in vitro as a useful model for human immunodeficiency virus (HIV) and its inhibition by test compounds has been described by Frank et al., Antimicrobial Agents and Chemotherapy 31(9), 1369-1374 (1987).
Inhibition of HIV-1 can be shown by tests involving plating of susceptible human host cells which are syncytium-sensitive with and without virus in microculture plates, adding various concentrations of the test compound, incubating the plates for 9 days (during which time infected, non-drug treated control cells are largely or totally destroyed by the virus), and then determining the number of remaining viable cells using a colorimetric endpoint.
DETAILED DESCRIPTION OF THE INVENTION
The following examples will further illustrate the invention although it will be understood that the invention is not limited to these specific examples or the details disclosed therein.
EXAMPLE 1
Preparation of 1,5-dideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-D-glucitol (2)
To a stirred solution of 1-deoxynojirimycin (100 g, 0.61 mol) in saturated aqueous sodium bicarbonate (1000 ml), benzyl chloroformate (95%, 121 g, 0.67 mol) was added dropwise at room temperature. After stirring at room temperature for 18 hr, the solution was extracted once with methylene chloride (300 ml) to remove any unreacted benzyl chloroformate. The aqueous layer was then extracted several times with ethyl acetate to give a total of 2.5-3 liters of the extract. The organic layer was then dried (Na 2 SO 4 ), filtered and concentrated to give (2) a white solid (98.57 g, 54%), mp 101°-2° C., Anal calcd. for C 14 H 19 NO 6 C, 56.56, H, 6.44, N, 4.71 Found c, 56.33 H, 6.38, N, 4.58., 1 H NMR (CD 3 OD) 7.2-7.4 (m, 5H), 5.15 (s, 2H), 4.23 (br m, 1H), 4.05 (br d., J=8 Hz, 1H), 3.87 (dd, J=6, 4 Hz, 1H), 3.78-3.85 (m, 2H), 3.70-3.78 (m, 2H), 3.45 (br d, J=8 Hz, 1H).
EXAMPLE 2
Preparation of 1,5-dideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-glucitol (3)
A mixture of (2) (98.5 g, 0.33 mol) , benzaldehyde dimethyl acetal (65.5 g, 0.43 mol) and p-toluenesulfonic acid (1 g) in a round bottom flask was dissolved in dimethlformamide (400 ml). The flask was connected to a water aspirator and the reaction was heated to 60°-65° C. for 4 hr. The reaction mixture was cooled to room temperature and poured into stirred ice-water (1200 ml) containing sodium bicarbonate (14 g). The white solid formed was filtered, washed with cold water and dried. Recrystallization using hexane/ethyl acetate gave 3 (96.2 g, 54%) as pure white solid, mp 147°-48° C., Anal calcd. for C 21 H 23 NO 6 C, 65.44, H, 6.02, N, 3.63 Found C, 65.15, H, 5.93, N, 3.49. IR (KBr) 3420, 1715, 1450, 1425, 1395, 1380, 1365, 1090 cm -1 ; 1 H NMR (CD 3 OD) 7.28-7.53 (m, 10H), 5.61 (s, 1H), 5.14 (s, 2H), 4.77 (dd, J=11, 4.6 Hz, 1H), 4.38 (t, J=11 Hz, 1H), 4.16 (dd, J=13.4, 4.2 HZ, 1H), 3.5-3.7 complex m, 3H), 3.35 (td, J=11, 4.6 HZ), 2.97 (dd, J=13.4, 9.3 Hz, 1H); 13 C NMR (CD 3 OD) 156.7, 139.4, 138.0, 129.9, 129.7, 129.3, 129.2, 129.1, 127.6, 102.8, 81.9, 77.5, 71.5, 70.6, 68.6, 55.9 and 50.5; MS (CI, NH 3 , m/e) 386 (M+1).
EXAMPLE 3
Preparation of 1,5-dideoxy-1,5-[{phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-glucitol, 2-(4-methylbenzenesulfonate) (4)
A mixture of diol 3 (46.3 g, 0.12 mol) and di-n-butyltin oxide (31.1 g, 0.125 mol) in methanol (300 ml) was refluxed for 2 hr. The methanol was removed, toluene was added and removed under vaccuum. The residue was dissolved in methylene chloride (300 ml) and triethylamine (20 ml, 0.144 mmol). After cooling to 0° C., p-toluenesulfonyl chloride (25.2 g, 0.132 mmol) was added. The reaction was stirred at 0° C. for 30 min and then warmed to 20° C. After stirring for 3 hr, the reaction was quenched by adding saturated aqueous sodium bicarbonate. The organic layer was separated and washed with water, 0.5M KHSO 4 and water successively. The organic layer was dried (Na 2 SO 4 ), filtered and concentrated. The residue was chromatographed (silica gel, hexane/ethyl acetate 7/3) to give pure 4 (50.27 g, 77%) as white solid, mp 115°-17° C., Anal calcd. for C 28 H 29 NO 8 S: C, 62.32, H, 5.42, N, 2.66 Found C, 62.65, H, 5.40, N, 2.62. 1 H NMR (CDCl 3 ) 7.82 (d, J=7.8 Hz, 2H), 7.35-7.50 (m, 10H), 7.31 (d, J=7.8 Hz, 2H), 5.51 s, (1H), 5.12 (s, 2H), 4.76 (dd, J=11.4, 4.5 Hz, 1H), 4.38 ddd, J=9.3, 7 6, 4.8 Hz, 1H), 4.32 (dd, J=11.4, 9.5 Hz, 1H), 4.31 (dd, J=13.6, 4.8 Hz, 1H), 3.78 (dt, J=2.6, 9.4Hz, 1H), 3.59 (t, J=9.4 Hz, 1H), 3.26 (ddd, J=11.4, 9.4, 4.5 Hz, 1H), 3.04 (dd, J=13.6, 9.3 Hz, 1H) 2.63 d, J=2.6 Hz, 1H), 2.41 (s, 3H); 13 C NMR (CDCl 3 ) 154.8, 145.2, 137.0, 135 8, 133.2, 129.8, 129.3, 128.7, 128.4, 128.3, 128.1, 126.2, 101.8, 79.9, 78.1, 73.9, 69.2, 67.8, 54.2, 47.1 and 21.7; MS (m/e) 546 (M+Li).
EXAMPLE 4
Preparation of 2,3-anhydro-1,5-dideoxy-1 5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-mannitol (5)
Sodium hydride (2.79 g, 60% dispersion in mineral oil, 69.66 mol) was placed in a flask under argon and washed three times with dry hexane. The residue was suspended in dry THF (300 ml) and to this a solution of 4 (37.6 g, 69.66 mmol) in THF (100 ml) was added slowly. After stirring for 18 hr, the reaction was quenched by adding water. The organic layer was extacted with ethyl acetate and washed with saturated aqueous sodium bicarbonate and brine. After drying (sodium sulfate) and filteration, the organic layer was concentrated and recrystallized using cyclohexane to give pure 5 (19.2 g, 75%) as white solid, mp 104°-5° C., Anal calcd. for C 21 H 21 NO 5 C, 68.64, H, 5.77, N, 3.81 Found C, 68.21, H, 5.84, N, 3.67. 1 H NMR (CDCl 3 ) 7.53-7.67 (m, 10H), 5.67 (s, 1H), 5.16 (s, 2H), 4.76 (broad s, 1H), 4.59 (d, J=15 Hz, 1H), 4.08 (d, J=10 Hz, 1H), 4.02 (dd, J=11.4, 4 Hz, 1H), 3.46 (dd, J=15, 0.9 HZ, 1H), 3.40 (d, J=3 Hz, 1H), 3.25 (d, J=3 Hz, 1H), 3.10 dt, J=4, 10 Hz, 1H); 13 C NMR (CDCl 3 ) 156.2, 137.8, 136.6, 129.7, 129.1, 128.9, 128.8, 128.5, 126.6, 102.8, 73.0, 70.4, 68.0, 56.0, 54.7, 50.4 and 46.6; MS (CI, NH 3 , m/e) 368 (M+H).
EXAMPLE 5
Synthesis of 2-azido-1,2,5-trideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-glucitol (7) and 3-azido-1,3,5-trideoxy- 1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-altritol (6)
To a solution of epoxide 5 (4 g, 10.9 mmol) in 2-methoxyethanol (80 ml), sodium azide (3.5 g, 54.5 mmol) and ammonium chloride (2.33 g, 43.6 mmol) were added. The reaction mixture was refluxed for 36 hr. Part of the solvent was removed under reduced pressure. The reaction mixture was diluted with ethyl acetate and washed with 1N HCl, water and brine. The organic layer was dried (MgSO 4 ), filtered and concentrated. The crude mixture was chromatographed (silica gel, hexane/ethyl acetate 8/2) to give pure 7 (1.95 g, 44%) and 6 (1.81 g, 41%). 6. DSC (mp) 253° C.; Anal calcd. for C 21 H 22 N 405 C, 61.46, H, 5.40, N, 13.65 Found C, 61 23, H, 5.46, N, 13.39 7. Anal calcd. for C 21 H 22 N 405 C, 61.46, H, 5.40, N, 13.65 Found C, 61.31, H, 5.56, N, 13.26.
EXAMPLE 6
Synthesis of 2-azido-1,2,5-trideoxy-1,5-imino-4,6-O-(R-phenylmethylene)-D-glucitol (8)
The compound 7 (3.3 g, 8.05 mol) was added to previously prepared solution of sodium hydroxide (4 g) in ethanol/water (1/1, 120 ml). After heating the mixture at 70° C. for 20 hr, the reaction was cooled and part of the solvent was removed under reduced pressure. The mixture was neutrallized with 1N HCl and extracted in methylene chloride. The organic layer was washed with water and brine. After drying (MgSO 4 ) and concentration of the filterate, the crude product (3.01 g) was chromatographed (silica gel, ethyl acetae/i-propanol 98/2) to give pure 8 (2.07 g, 93%). Anal calcd. for C 13 H 16 N 403 C, 56.51, H, 5.84, N, 20.28 Found C, 56.56, H, 5.93, N, 20.15.
EXAMPLE 7
Synthesis of 2-azido-1,5-(butylimino)-1,2,5-trideoxy-4,6-O-(R-phenylmethylene)-D-glucitol (9)
To a solution of 8 (3.1 g, 11.23 mmol) in methanol (i20 ml), molecular sieves (4 Å, 3.5 g) were added. After stirring for 5 min, butyraldehyde (1.86 ml, 20.8 mol), acetic acid (1.3 ml) and sodium cyanoborohydride (95%, 1.02 g, 15.4 mmol) were added. The reaction was stirred at 22° C. for 18 hr, filtered and the residue washed with more ethyl acetate. The combined organic fractions were concentrated. The residue was redissolved in ethyl acetate and washed with aqueous potassium carbonate, water and brine. After drying (MgSO 4 ) and concentration, the crude (4.08 g) was chromatographed (silica gel, hexane/ethyl acetate 6/4) to give 9 (3.28 g, 88%) as white solid. DSC (mp) 115° C. (dec.); Anal calcd. for C 17 H 24 N 403 C, 61.43, H, 7.28, N, 16.85 Found C, 61.40, H, 7.34, N, 16.84.
EXAMPLE 8
Synthesis of 2-azido-1,5-{(2-ethylbutyl)imino}-1,2,5-trideoxy-4,6-O-(R-phenylmethylene)-D-glucitol (10)
To a solution of 8 (1.07 g, 3.87 mmol) in methanol (35 ml), molecular sieves (4 Å, 2.1 g) were added. After stirring for 5 min, 2-ethylbutyraldehyde (1.04 ml, 7.74 mol), acetic acid (0.35 ml) and sodium cyanoborohydride (95%, 390 mg, 5.8 mmol) were added. The reaction was stirred at 22° C. for 20 hr, filtered and the residue washed with more ethyl acetate. The combined organic fractions were concentrated. The residue was redissolved in ethyl acetate and washed with aqueous potassium carbonate, water and brine. After drying (MgSO 4 ) and concentration, the crude (1.47 g) was chromatographed (silica gel, hexane/ethyl acetate 8/2) to give pure 10 (650 mg, 47%). Anal calcd. for C 19 H 28 N 403 C, 62.68, H, 7.86, N, 15.39 Found C, 62 72, H, 7.94, N, 15.16.
EXAMPLE 9
Synthesis of 2-azido-1,5-{(4,4,4-trifluorobutyl)imino}-1,2,5-trideoxy-4,6-O-(R-phenylmethylene)-D-glucitol (11)
To a solution of 8 (500 mg, 1.81 mmol) in dimethylformamide (10 ml), 1-bromo-4,4,4-trifluorobutane (375 mg, 1.96 mmol) and potassium carbonate (150 mg, 1.08 mmol) were added. The reaction was immersed in an oil-bath at 60° C. and stirred for 60 hr. More 1-bromo-4,4,4-trifluorobutane (375 mg, 1.96 mmol) was added and the reaction was heated at 60° C. for 24 hr. The solvent was removed under reduced pressure and the reaction mixture was neutralized with 1N HCl. The mixture was extracted in methylene chloride and the extract was washed with aqueous potassium carbonate and brine. After drying (MgSO 4 ) and concentration, the crude (610 mg) was chromatographed (silica gel, hexane/ethyl acetate 6/4) to give pure 11 (510 mg, 73%) as thick liquid. 1 H NMR (CDCl 3 ) 7.49 (m, 2H), 7.39 (m, 3H), 5.49 (s, 1H), 4.34 (dd, J=11, 4 Hz, 1H) 3.63 (dd, J=11, 10 Hz, 1H), 3.45-3.60 (complex band, 2H), 3.48 (t, J=9 Hz, 1H), 3.10 (d, J=2 Hz, 1H), 2.97 (dd, J=12, 5 Hz, 1H), 2.55 (dt, J=13, 5 Hz, 1H), 2.36 (td, J=10, 4 Hz, 1H), 2.30 (dt, J=13, 7 Hz, 1H), 1.90-2.22 (complex band, 3H), 1.68 (d, J=7.5 Hz, 1H).
EXAMPLE 10
Synthesis of 2-azido-1,2,5-trideoxy-1,5-imino-D-glucitol (12)
A solution of 8 (1 g, 3.61 mmol) in trifluoroacetic acid/water (4/1, 15 ml) was stirred at 22° C. for 18 hr. The solvent was removed under reduced pressure and the residue as thick yellow liquid was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/methanol/ammonium hydroxide 50/50/2.5), were pooled and concentrated. The water in the fractions was azeotropically removed With toluene and 12 (394 mg, 74%) was isolated as a white solid after crystallization from methanol/hexane, mp 142° C. (dec). Anal calcd. for C 6 H 12 N 4 O 3 .25H 2 O C, 39.86, H, 6.64, N, 27.75 Found C, 39.91, H, 6.79, N, 27.59.
EXAMPLE 11
Synthesis of 2-azido-1,5-(butylimino)-1,2,5-trideoxy-D-glucitol (13)
A solution of 9 (650 mg, 1.96 mmol) in trifluoroacetic acid/water (4/1, 12 ml) was stirred at 22° C. for 8 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/i-propanol/water/ammonium hydroxide 70/25/5/2), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give 13 (330 mg) which Was rechromatographed (silica gel, ethyl acetate i-propanol/water ammonium hydroxide 70/25/5/2) to give pure 13 (260 mg, 61%) as thick liquid. Anal calcd. for C 10 H 20 N 4 O 3 .2H 2 O C, 48.45, H, 8.29, N, 22.60 Found C, 48.49, H, 8.31, N, 22.41.
EXAMPLE 12
Synthesis of 2-azido-1,5-{(2-ethylbutyl)imino}-1,2,5-trideoxy-D-glucitol (14)
A solution of 10 (250 mg, 0.69 mmol) in trifluoroacetic acid/water (4/1, 7 ml) was stirred at 22° C. for 18 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/i-propanol/water/ammonium hydroxide 70/25/5/2), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give 14 (151 mg) which was rechromatographed (silica gel, ethyl acetate/i-propanol/water/ammonium hydroxide 70/25/5/2) to give pure 14 (52 mg, 27%). DSC (mp) 127° C. (dec). Anal calcd. for C 12 H 24 N 4 O 3 C, 52.92, H, 8.88, N, 20.57 Found C, 52.67, H, 8.91, N, 20.48.
EXAMPLE 13
Synthesis of 2-azido-1,5-{(4,4,4-trifluorobutyl)imino}-1,2,5-trideoxy-D-glucitol (15)
A solution of 11 (500 mg, 1.29 mmol) in trifluoroacetic acid/water (4/1, 25 ml) was stirred at 22° C. for 24 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/i-propanol/water/ammonium hydroxide 70/25/5/2), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 15 (320 mg) which was rechromatographed (silica gel, ethyl acetate/i-propanol/water/ammonium hydroxide 70/25/5/2) to give pure 15 (272 mg, 70%) as white solid. DSC (mp) 107° C. (dec). Anal calcd. for C 10 H 17 N 4 O 3 F 3 C, 40.27, H, 5.75, N, 18.78 Found C, 40.12, H, 5.71, N, 18.60.
EXAMPLE 14
Synthesis of 2-amino-1,5-(butylimino)-1,2,5-trideoxy-4,6-O-(R-phenylmethylene)-D-glucitol (17)
To a solution of 9 (700 mg, 2.11 mmol) in methanol (70 ml) in a Parr hydrogenation flask, 10% Pd on C (70 mg) was added. The system was sealed, purged with nitrogen (5 times) and hydrogen (5 times) and then pressurized to 5 psi hydrogen. After running the reaction on a shaker for 3.5 hr, the system was vented, purged with nitrogen and filtered. The filtrate was concentrated and the crude (630 mg) was chromatographed (silica gel, methylene chloride/methanol/ammonium hydroxide 90/10/1) to give pure 17 (600 mg, 93%). DSC (mp) 125° C. Anal calcd. for C 17 H 26 N 2 O 3 C, 66.64, H, 8.55, N, 9.14 Found C, 66.14, H, 8.56, N, 9.08.
EXAMPLE 15
Synthesis of 2-amino-1,5-{(2-ethylbutyl)imino}-1,2,5-trideoxy-4,6-O-(R-phenylmethylene)-D-glucitol (18)
To a solution of 10 (350 mg, 0.97 mmol) in methanol (50 ml) in a Parr hydrogenation flask, 10% Pd on C (35 mg) was added. The system was sealed, purged with nitrogen (5 times) and hydrogen (5 times) and then pressurized to 5 psi hydrogen. After running the reaction on a shaker for 3 hr, the system was vented, purged with nitrogen and filtered. The filtrate was concentrated and the crude (320 mg) was chromatographed (silica gel, methylene chloride/methanol/ammonium hydroxide 90/10/1) to give pure 18 (240 mg, 78%). Anal calcd. for C 19 H 30 N 2 O 3 C, 68.23, H, 9.04, N, 8.38 Found C, 68.87, H, 9.01, N, 7.48.
EXAMPLE 16
Synthesis of 2-amino-1,5-{(4,4,4-trifluorobutyl)imino}-1,2,5-trideoxy-4,6-O-(R-phenylmethylene)-D-glucitol (19)
To a solution of 11 (1.4 g, 3.63 mmol) in methanol (25 ml) in a Parr hydrogenation flask, 10% Pd on C (140 mg) was added. The system was sealed, purged with nitrogen (5 times) and hydrogen (5 times) and then pressurized to 5 psi hydrogen. After running the reaction on a shaker for 21 hr, the system was vented, purged with nitrogen and filtered. The filtrate was concentrated and the crude (1.3 g) was chromatographed (silica gel, methylene chloride/methanol/ammonium hydroxide 90/10/1) to give pure 19 (1.15 g, 88%). Anal calcd. for C 17 H 23 N 2 O 3 F 3 0.4H 2 O C, 55.55, H, 6.53, N, 7 62 Found C, 55.55, H, 6.36, N, 7.59.
EXAMPLE 17
Synthesis of 2-amino-1,2,5-trideoxy-1,5-imino-D-glucitol (20)
To a solution of 12 (465 mg, 3.14 mmol) in methanol (50 ml) in a Parr hydrogenation flask. 10% Pd on C (50 mg) was added. The system was sealed, purged with nitrogen (5 times) and hydrogen (5 times) and then pressurized to 5 psi hydrogen. After running the reaction on a shaker for 3.5 hr, the system was vented, purged with nitrogen and filtered. The filtrate was concentrated to give pure 20 (365 mg, 91%). DSC (mp) 184° C. Anal calcd. for C 6 H 14 N 2 O 3 0.25H 2 O C, 43.23, H, 8.77, N, 16.81 Found C, 43.42, H, 8.43, N, 16.47.
EXAMPLE 18
Synthesis of 2-amino-1,5-(butylimino)-1,2,5-trideoxy-D-glucitol (21)
A solution of 17 (580 mg, 1.89 mmol) in trifluoroacetic acid/water (4/1, 15 ml) was stirred at 22° C. for 24 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/methanol/ammonium hydroxide 50/50/2.5), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 21 (410 mg) which was rechromatographed (silica gel, ethyl acetate/methanol/ammonium hydroxide 50/50/2.5) to give pure 21 (302 mg, 73%). DSC (mp) 108° C. Anal calcd. for C 10 H 22 N 2 O 3 0.3H 2 O C, 53.69, H, 10.18, N, 12.52 Found C, 53.63, H, 10.02, N, 12.34.
EXAMPLE 19
Synthesis of 2-amino-1,5-{(2-ethylbutyl)imino}-1,2,5-trideoxy-D-glucitol (22)
A solution of 18 (140 mg, 0 42 mmol) in trifluoroacetic acid/water (4/1, 10 ml) was stirred at 22° C. for 8 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/i-propanol/ammonium hydroxide 50/50/2.5), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 22 (120 mg) which was rechromatographed (silica gel, ethyl acetate/i-propanol/ammonium hydroxide 50/50/2.5) to give pure 22 (72 mg, 70%). DSC (mp) 130° C. Anal calcd. for C 12 H 26 N 2 O 3 0.75H 2 O C, 55.46, H, 10.67, N, 10.78 Found C, 55.33, H, 10.05, N, 10.54.
EXAMPLE 20
Synthesis of 2-amino-1,5-{(4,4,4-trifluorobutyl)imino}-1,2,5-trideoxy-D-glucitol (23)
A solution of 19 (400 mg, 1.1 mmol) in trifluoroacetic acid/water (4/1, 10 ml) was stirred at 22° C. for 8 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/i-propanol/ammonium hydroxide 50/50/2.5), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 23 (280 mg) which was rechromatographed (silica gel, ethyl acetate/i-propanol/ammonium hydroxide 50/50/2.5) to give pure 23 (265 mg, 87%). Anal calcd. for C 10 H 19 N 2 O 3 F 3 0.3H 2 O C, 43.26, H, 7.11, N, 10.09 Found C, 43.23, H, 6.86, N, 9.59.
EXAMPLE 21
Synthesis of 1,5-(butylimino)-1,2,5-trideoxy-2-(dimethylamino)-4,6-O-(R-phenylmethylene)-D-glucitol (24) and 1,5-(butylimino)-1,2,5-trideoxy-2-(methylamino)-4,6-O-(R-phenylmethylene)-D-glucitol (25)
To a solution of 17 (792 mg, 2.59 mmol) in methanol (75 ml) in a Parr hydrogenation flask, 4% Pd on C (100 mg) and formaldehyde (0.23 ml) were added. The system was sealed, purged with nitrogen (5 times) and hydrogen (5 times) and then pressurized to 5 psi hydrogen. After running the reaction on a shaker for 21 hr, the system was vented, purged with nitrogen and filtered. The filtrate was concentrated and the crude (560 mg) was chromatographed (silica gel, methylene chloride/methanol/ammonium hydroxide 90/10/1) to give 24 (310 mg, 36%) and 25 (372 mg, 45%). 24. 1 H NMR (CDCl 3 ) 7.52 (m, 2H), 7.34 (m, 3H), 5.52 (s, 1H), 4.37 (dd, J=11, 5 Hz, 1H), 3.83 (brs, 1H), 3.65 (dd, J=11, 10 Hz, 1H), 3.60 (t, J=9 Hz, 1H), 3.54 (t, J=9 Hz, 1H), 2.93 (dd, J=11, 4 Hz, 1H), 2.63 (ddd, J=11, 9, 4 Hz, 1H), 2.53 (dt, J=13, 8 Hz, 1H), 2.35 (s, 6H), 2.22-2.37 (complex band, 2H), 2.14 (t, J=11 Hz, 1H), 1.42 (m, 2H), 1.27 (m, 2H), 0.92 (t, J=7 Hz, 3H).
25. 1 H NMR (CDCl 3 ) 7.49 (m, 2H), 7.34 (m, 3H), 5.49 (s, 1H), 4.36 (dd, J=11, 4 Hz, 1H), 3.65 (dd, J=11, 10 Hz, 1H), 3.48 (t, J=9 Hz, 1H), 3.36 (dd, J=10, 9 Hz, 1H), 3.25 (broad s, 1H), 3.05 (dd, J=11, 5 Hz, 1H), 2.57 (td, J=10, 5 Hz, 1H), 2.51 dt, J=13, 8 HZ, 1H), 2.39 ddd, J=10 , 9, 4 Hz, 1H), 2.37 (s, 3H), 2.30 (ddd, J=13, 8, 6 Hz, 1H), 2.00 (t, J=11 Hz, 1H), 1.42 (m, 2H), 1.26 (m, 2H , 0.92 t, J=7 Hz, 3H).
EXAMPLE 22
1,5-(butylimino)-1,2,5-trideoxy-2-{(1-oxobutyl)amino}-4,6-O-(R-phenylmethylene)-D-glucitol, 3-butanoate (26)
To a solution of 17 (650 mg 2.12 mmol) in pyridine (8 ml), butyric anhydride (2 ml) was added and the reaction mixture was stirred at room temperature. After stirring for 18 hr, the reaction mixture was poured over ice and extracted with methylene chloride. The organic layer was washed with water and brine. After drying over MgSO 4 , the extract was filtered and the solvent removed under reduced pressure. The crude product 26 (1.01 g) was used in the next step without further purification. 1 H NMR (CDCl 3 ) 7.45 (m, 2H), 7.36 (m, 3H), 5.86 (d, J=7.5 Hz, 1H), 5.53 (s, 1H), 4.92 (t, J=10 Hz, 1H), 4.43 (dd, J=11, 5 Hz, 1H), 4.16 (tdd, J=10, 7.5, 5 Hz, 1H), 3.74 (t, J=10 Hz, 1H), 3.73 (dd, J= 11, 10 Hz, 1H), 3.25 (dd, J=12, 5 Hz, 1H), 2.55 (dt, J=13, 8 Hz, 1H), 2.46 (td, J=10, 5 Hz, 1H), 2.35 (dt, J=15, 7.5 Hz, 1H), 2.29 (dt, J=15, 7.5 Hz, 1H), 2.27 (dt, J=13, 7 Hz, 1H), 2.10 (t, J=7.5 Hz, 2H), 2.06 (dd, J=12, 10 Hz, 1H), 1.62 (m, 4H), 1.41 (m, 2H), 1.27 (m, 2H), 0.93 (t, J=7.5 Hz, 1H), 0.90 (t, J=7.5 Hz, 1H).
EXAMPLE 23
1,5- butylimino)-1,2,5-trideoxy-2-{(1-oxobutyl)amino}-4,6-O-(R-phenylmethylene)-D-glucitol (27)
To a solution of 26 (900 mg, 2.01 mmol) in methanol (50 ml), saturated aqueous potassium carbonate (30 ml) was added and the mixture was stirred at room temperature for 4 hr. After neutrallizing with conc. HCl to pH 7, methanol was removed under reduced pressure and the reaction mixture was extracted with ethyl acetate. The organic layer was washed with water and brine, dried (MgSO 4 ) and filtered. The concentration of the extract gave 27 (720 mg, 90%). mp 172° C. (dec), Anal calcd. for C 21 H 32 N 2 O 4 , C, 66.99, H, 8.57, N, 7.44 Found C, 66.82, H, 8.68, N, 7.36.
EXAMPLE 24
Synthesis of 1,5-(butylimino)-1,2,5-trideoxy-2-(dimethylamino)-D-glucitol (28)
A solution of 24 (580 mg, 1.74 mmol) in trifluoroacetic acid/water (4/1, 10 ml) Was stirred at 22° C. for 24 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/i-propanol/ammonium hydroxide 50/50/2.5), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 28 (300 mg) which was rechromatographed (silica gel, ethyl acetate/i-propanol/ammonium hydroxide 50/50/2.5) to give pure 28 (260 mg, 61%). DSC (mp) 111° C., Anal calcd. for C 12 H 26 N 2 O 3 0.2 H 2 O, C, 57.66, H, 10.65, N, 11.21 Found C, 57.88, H, 10.63, N, 11.23.
EXAMPLE 25
Synthesis of 1,5-(butylimino)-1,2,5-trideoxy-2-(methylamino)-D-glucitol (29)
A solution of 25 (610 mg, 1.91 mmol) in trifluoroacetic acid water (4/1, 10 ml) Was stirred at 22° C. for 24 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/i-propanol/ammonium hydroxide 50/50/2.5), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 29 (480 mg) which was rechromatographed (silica gel, ethyl acetate/i-propanol/ammonium hydroxide 50/50/2.5) to give pure 29 (310 mg, 70%). Anal calcd. for C 11 H 24 N 2 O 3 0.4 H 2 O, C, 55.16, H, 10.44, N, 11.70 Found C, 55.24, H, 10.57, N, 11.74.
EXAMPLE 26
1,5- butylimino)-1,2,5-trideoxy-2-{(1-oxobutyl)amino}-D-glucitol (30)
A solution of 27 (250 mg, 0.66 mmol) in trifluoroacetic acid/water (4/1, 10 ml) was stirred at 22° C. for 24 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/i-propanol/water/ammonium hydroxide 70/25/5/2), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 30 (180 mg) which was rechromatographed (silica gel, ethyl acetate/i-propanol/water/ammonium hydroxide 70/25/5/2) to give pure 30 (165 mg, 86%). DSC (mp) 203° C., Anal calcd. for C 14 H 28 N 2 O 4 0.5 H 2 O, C, 56.54, H, 9.83, N, 9.42 Found C, 56.32, H, 9.50, N, 9.26.
EXAMPLE 27
1,5-(butylimino -1,2,5-trideoxy-2-{(1-oxobutyl)amino}-D-glucitol, tributanoate (31)
To a solution of 30 (100 mg 0.34 mmol) in pyridine (8 ml), butyric anhydride (2 ml) was added and the reaction mixture was stirred at room temperature. After stirring for 40 hr, the reaction mixture was poured over ice and extracted with methylene chloride. The organic layer was washed with water and brine. After drying over MgSO 4 , the extract was filtered and the solvent removed under reduced pressure. The crude product (280 mg) was chromatographed (silica gel, hexane/ethyl acetate 6/4) to give pure 31(98 mg, 57%). DSC (mp) 84° C. (dec), Anal calcd. for C 26 H 46 N 2 O 7 , C, 62.63, H, 9.30, N, 5.62 Found C, 62.17, H, 9.30, N, 5.32.
EXAMPLE 28
Synthesis of phenylmethyl 8β-azidohexahydro-7-oxo-2R-2α-phenyl-5H-4aα, 8aβ-1,3-dioxino[5,4-b]pyridine-5-carboxylate (32)
To a cold solution of dimethyl sulfoxide (5.6 ml, 78 mmol) in methylene chloride (50 ml) at -70° C., trifluoroacetic anhydride (8.32 ml, 59 mmol) in methylene chloride (50 ml) was added over 20 min. After stirring for 15 min, a solution of 6 (16 g, 39 mmol) in methylene chloride (150 ml) was added over 30 min. at -70° C. The temperature of reaction mixture was allowed to rise to -30° C. over 4 hr and then the reaction was stirred at -30° C. for 1 hr. After recooling to -70° C., triethylamine (15 ml, 107 mmol) was added and the reaction was warmed to 22° C. in about an 1 hr and stirred at 22° C. for about 8 hr. The reaction was diluted with methylene chloride and washed with water and brine. After drying (MgSO 4 ), filteration and concentration, the crude (17.8 g) was chromatographed (silica gel, hexane/ethyl acetate 1/1) to give pure 32 (13.9 g, 86%). 1 H NMR (CDCl 3 ) 7.30-7.49 (complex band, 10H), 5.71 (s, 1H), 5.13 (s, 2H), 4.85 (d, J=11 Hz, 1H), 4.61 (dd, J=11, 4 Hz, 1H), 4.33 (dd, J=11, 10 Hz, 1H), 4.30 (d, J=18 Hz, 1H), 4.20 (d, J=18 Hz, 1H), 4.11 (dd, J=11, 10, 1H), 3 85 (dt, J=10, 4 Hz, 1H).
EXAMPLE 29
3-azido-1,3,5-trideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-glucitol (33) and 3-azido-1,3,5-trideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-mannitol (34)
To a cold solution of 32 (2.5 g, 6.12 mmol) in THF (100 ml) at -78° C., diisobutylaluminum hydride (9.25 ml, 1M solution in toluene, 9.25 mmol) was added over 10 min. After stirring at -78° C. for 4 hr, methanol (2.5 ml) was added. The reaction was stirred for 10 min, the cold bath was removed and the reaction allowed to rise to 22° C. and stirred for 30 min. After quenching with 0.5N HCl (10 ml), the reaction was diluted with ethyl acetate and washed with water and brine. The organic extract was dried (MgSO 4 ), filtered and concentrated to give crude mixture (2.23 g) as thick orange liquid. Chromatographic purification (silica gel, hexane/ethyl acetate 1/1) gave 33 (1.57 g, 63%) and 34 (231 mg, 9%). 33. Anal calcd. for C 21 H 22 N 4 O 5 , C, 61.46, H, 5.40, N, 13.65 Found C, 61.62, H, 5.53, N, 12.48. 34. Anal calcd. for C 21 H 22 N 4 O 5 , C, 61.46, H, 5.40, N, 13.65 Found C, 61.37, H, 5.43, N, 13.39.
EXAMPLE 30
3-azido-1,3,5-trideoxy-1,5-imino-4,6-O-(R-phenylmethylene)-D-glucitol (35)
The compound 33 (1.8 g, 4.39 mol) was added to previously prepared solution of sodium hydroxide (2 g) in ethanol/water (1/1, 60 ml). After heating the mixture at 75°-80° C. for 20 hr, the reaction was cooled and part of the solvent was removed under reduced pressure. The mixture was neutrallized with 1N HCl and extracted in methylene chloride. The organic layer was washed with water and brine. After drying (MgSO 4 ) and concentration of filterate, the crude product 3.01 g) was chromatographed (silica gel, methylene chloride/methanol/ammonium hydroxide 90/10/1) to give pure 35 (1.1 g, 91%). DSC (mp) 192° C., Anal calcd. for C 13 H 16 N 4 O 3 , C, 56.51, H, 5.84, N, 20.28 Found C, 56.26, H, 5.90, N, 20.08.
EXAMPLE 31
3-amino-1,3,5-trideoxy-1,5-imino-4,6-O-(R-phenylmethylene)-D-glucitol (36)
To a solution of 35 (700 mg, 2.54 mmol) in methanol (50 ml) in a Parr hydrogenation flask, 4% Pd on C (150 mg) was added. The system was sealed, purged with nitrogen (5 times) and hydrogen (5 times) and then pressurized to 5 psi hydrogen. After running the reaction on a shaker for 10 hr, the system was vented, purged with nitrogen and filtered. The filtrate was concentrated and the crude (700 mg) was chromatographed (silica gel, methylene chloride/methanol/ammonium hydroxide 90/10/1) to give pure 36 (590 mg, 93%). Anal calcd. for C 13 H 18 N 2 O 3 0.25H 2 O, C, 61.28, H, 7.32, N, 10.99 Found C, 61.27, H, 7.29, N, 10.72.
EXAMPLE 32
3-amino-1,3,5-trideoxy-1,5-imino-D-glucitol (37)
A solution of 36 (480 mg, 1.92 mmol) in trifluoroacetic acid/water (4/1, 8 ml) was stirred at 22° C. for 24 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/methanol/ammonium hydroxide 25/75/3), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 37 which was rechromatographed (silica gel, ethyl acetate/methanol/ammonium hydroxide 25/75/3) to give pure 37 (135 mg, 32%). DSC (mp) 191° C., Anal calcd. for C 6 H 14 N 2 O 3 0.25H20, C, 43.23, H, 8.77, N, 16.81 Found C, 43.66, H, 8.61, N, 16.19.
EXAMPLE 33
Synthesis of 2-azido-1,2,5-trideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-glucitol, methanesulfonate (38)
To a solution of 7 (3.8 g, 9.27 mmol) in pyridine (40 ml), methanesulfonyl chloride (860 μl, 11.11 mmol) was injected over 10 min. After stirring at 22° C. for 20 hr, the reaction contents were poured over ice and extracted in ethyl acetate (2×700). The combined organic extracts were washed with saturated aqueous potassium carbonate, water and brine. After drying (MgSO 4 ), filteration and concentration, the crude (6.45 g) was chromatographed (silica gel, hexane/ethyl acetate 6/4) to give pure 38 (4.3 g, 95%) as white solid. DSC (mp) 222° C., Anal calcd for C 22 H 24 N 4 O 7 S 1H20, C, 52.17, H, 5.17, N, 11.06 Found C, 52.29, H, 4.81, N, 10.87.
EXAMPLE 34
Synthesis of 2-azido-1,2,5-trideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-allitol, acetate (39)
A mixture of 38 (2.3 g, 4.7 mmol), cesium acetate (9 g, 47 mmol), 18-crown-6 (1.16 g, 4.7 mmol) in toluene (50 ml) was refluxed for 72 hr. The reaction was cooled, filtered and the residue washed with more toluene. The combined organic fractions were concentrated and the crude (3.36 g) was chromatographed (silica gel, hexane/ethyl acetate 7/3) to give pure 39 (1.1 g, 52%) as white solid in addition to the starting material 38 (0.31 g, 14%). 39. 1 H NMR (CDCl 3 ) 7.31-7.45 (complex band, 10H), 5.74 (td, J=3, 1 Hz, 1H), 5.56 (s, 1H), 5.15 (d, J=12 Hz, 1H). 5.11 d, J=12 Hz, 1H), 4.84 (dd, J=12, 5 Hz, 1H), 4.48 (dd, J=12, 10 Hz, 1H), 4.32 (ddd, J=13, 5, 1 Hz, 1H), 3.79 (dd, J=10, 3 Hz, 1H), 3.61 (td, J=10, 5 Hz, 1H), 3.52 (ddd, J=11, 5, 3 Hz, 1H), 3.16 dd, J=13, 11 Hz, 1H), 2.17 s, 3H).
EXAMPLE 35
Synthesis of 2-azido-1,2,5-trideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-allitol (40A) and 2-azido-1,2,5-trideoxy-1,5-{(methoxycarbonyl)imino}-4,6-O-(R-phenylmethylene)-D-allitol (40B)
A mixture of 39 (970 mg, 2.15 mmol) and sodium methoxide (400 mg, 7.4 mmol) in methanol (50 ml) was refluxed for 18 hr. The reaction was cooled, neutrallized with 1N HCl and the solvent removed under reduced pressure. The residue was suspended in ethyl acetate and washed with saturated aqueous potassium carbonate, water and brine. The combined organic extracts were concentrated and the crude (1.02 g) chromatographed (silica gel, hexane/ethyl acetate 7/3) to give 40A (550 mg, 57%) and 40B (270 mg, 35%).
40A. 1 H NMR (CDCl 3 ) 7.45 (m, 2H), 7.34 (m, 8H), 5.55 (s, 1H), 5.10 (d, J=12 Hz, 1H). 5.07 (d, J=12 Hz, 1H), 4.79 (dd, J=12, 5 Hz, 1H), 4.45 (dd, J=12, 10 Hz, 1H), 4.22 (broad s, 1H), 4.17 (m, 1H), 3.62 (td, J=10, 5 Hz, 1H), 3.54 (dt, J=10, 2 Hz, 1H), 3.24 (m, 1H), 3.21 (m, 1H), 2.87 (s, 1H).
40B. 1 H NMR (CDCl 3 ) 7.47 (m, 2H), 7.37 (m, 3H), 5.59 (s, 1H), 4.81 (dd, J=12, 4 Hz, 1H), 4.48 (dd, J=12, 9 Hz, 1H), 4.27 (broad s, 1H), 4.12 (dd, J=12, 2 Hz, 1H), 3.67 (s, 3H), 3 65 (m, 1H), 3.60 (m, 1H), 3.30 (m, 1H), 3.23 (m, 1H), 2.82 (broad s, 1H).
EXAMPLE 36
Synthesis of 2-azido-1,2,5-trideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-allitol, methanesulfonate (41A)
To a solution of 40A (550 mg, 1.34 mmol) in pyridine (10 ml), methanesulfonyl chloride (140 μl, 1.74 mmol) was injected over 10 min. After stirring at 22° C. for 60 hr, the reaction contents were poured over ice and extracted in ethyl acetate. The combined organic extracts were washed with saturated aqueous potassium carbonate, water and brine. After drying (MgSO 4 ), filteration and concentration, the product obtained 41A (603 mg, 92%) was used in the next step without further purification. 1 H NMR (CDCl 3 ) 7.44 (m, 2H), 7.35 (m, 8H), 5.58 (s, 1H), 5.15 (broad t, J=2.5 Hz, 1H), 5.11 (s, 2H), 4.87 (dd, J=12, 5 Hz, 1H), 4.45 (dd, J=12, 10 Hz, 1H), 4.31 (dd, J=13, 5 Hz, 1H), 3.80 (dd, J=10, 2 Hz, 1H), 3.60 (ddd, J=12, 5, 3 Hz, 1H), 3.56 (td, J= 10, 5 Hz, 1H), 3.10 (dd, J=13, 12 Hz, 1H), 2.92 (s, 3H).
EXAMPLE 37
Synthesis of 2-azido-1,2,5-trideoxy-1,5-{(methoxycarbonyl)imino}-4,6-O-(R-phenylmethylene)-D-allitol, methanesulfonate (41B)
To a solution of 40B (217 mg, 0.65 mmol) in pyridine (5 ml), methanesulfonyl chloride (65 μl, 0.84 mmol) was injected over 10 min. After stirring at 22° C. for 30 hr, the reaction contents were poured over ice and extracted in ethyl acetate. The combined organic extracts were washed with saturated aqueous potassium carbonate, water and brine. After drying (MgSO 4 ), filteration and concentration, the product obtained 41B (320 mg, 92%) was used in the next step without further purification. 1 H NMR (CDCl 3 ) 7.46 (m, 2H), 7.35 (m, 3H), 5.61 (s, 1H), 5.18 (broad t, J=2.5 Hz, 1H), 4.88 (dd, J=12, 5 Hz, 1H), 4.48 (dd, J=12, 10 Hz, 1H), 4.28 (dd, J=13, 5 Hz, 1H), 3.83 (dd, J=10, 2 Hz, 1H), 3.70 (s, 3H), 3.66 (ddd, J=12, 5, 3 Hz, 1H), 3.58 (td, J=10, 5 Hz, 1H), 3.12 (dd, J=13, 12 Hz, 1H), 2.95 (s, 3H).
EXAMPLE 38
Synthesis of 2,3-diazido-1,2,3,5-tetradeoxy-1,5-{(methoxycarbonyl)imino}-4,6-O-(R-phenylmethylene)-D-glucitol (42B)
To a solution of 41B (320 mg, 0.77 mmol) in dimethylformamide (10 ml), sodium azide (252 mg, 3.88 mmol) was added. The reaction mixture was heated at 100°-10° C. for 30 hr. Part of the solvent was removed under reduced pressure. The reaction mixture was diluted with ethyl acetate and washed with aqueous potassium carbonate, water and brine. The organic layer was dried (MgSO 4 ), filtered and concentrated. The crude 42B (190 mg, 69%) was used in the next step without further purification. 1 H NMR (CDCl 3 ) 7.50 (m, 2H), 7.37 (m, 3H), 5.62 (s, 1H), 4.79 (dd, J=12, 5 Hz, 1H), 4.45 (dd, J=12, 10 Hz, 1H), 4.28 (dd, J=14, 5 Hz, 1H), 3.68 (s, 3H), 3.67 (t, J=10 Hz, 1H), 3.50 (t, J=10 Hz, 1H), 3.30 (ddd, J=11, 10, 5 Hz, 1H), 3.20 (td, J=10, 5 Hz, 1H), 2.64 (dd, J=14, 11 Hz, 1H).
EXAMPLE 39
Synthesis of 2,3-diazido-1,2,3,5-tetradeoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-glucitol(42A)
To a solution of 41A (600 mg, 1.23 mmol) in dimethylformamide (10 ml), sodium azide (400 mg, 6.15 mmol) was added. The reaction mixture was heated at 100°-10° C. for 72 hr. Part of the solvent was removed under reduced pressure. The reaction mixture was diluted with ethyl acetate and washed with aqueous potassium carbonate, water and brine. The organic layer was dried (MgSO 4 ), filtered and concentrated. The crude mixture (760 mg) consisting of 42A and 43 was hydrolyzed to 43 without purification.
EXAMPLE 40
Synthesis of 2,3-diazido-1,2,3,5-tetradeoxy-1,5-imino-4,6-O-(R-phenylmethylene)-D-glucitol(43)
The mixture of 42A, 42B and 43 (920 mg) obtained in the above steps was added to previously prepared solution of sodium hydroxide (2 g) in ethanol/water (1/1, 60 ml). After refluxing the mixture for 20 hr, the reaction was cooled and part of the solvent was removed under reduced pressure. The mixture was neutrallized with 1N HCl and extracted in ethyl acetate. The organic layer was washed with water and brine. After drying (MgSO 4 ) and concentration of filterate, the crude product (280 mg) was chromatographed (silica gel, methylene chloride/ethanol 98/2) to give pure 43. (360 mg, 68% in two steps). 1 H NMR (CDCl 3 ) 7.56 (m, 2H), 7.43 (m, 3H), 5.61 (s, 1H), 4.23 (dd, J=11, 5 Hz, 1H), 3.58 (dd, J=11, 10 Hz, 1H), 3.53 (dd, J=10, 9 Hz, 1H), 3.42 (dd, J= 10, 9 Hz, 1H), 3.29 (td, J=10, 5 Hz, 1H), 3.21 (dd, J=12, 5 Hz, 1H), 2.71 (td, J=10, 5 Hz, 1H), 2.54 (dd, J=12, 10 Hz, 1H), 1.15 (broad s, 1H).
EXAMPLE 41
2,3 diazido-1,5-(butylimino)-1,2,3,5-tetradeoxy-4,6-O-(R-phenylmethylene)-D-glucitol(44)
To a solution of 43 (360 mg, 1.19 mmol) in methanol (10 ml), molecular sieves (4 Å, 0.7 g) were added. After stirring for 5 min, butyraldehyde (0.22 ml, 2.4 mol), acetic acid (0.2 ml) and sodium cyanoborohydride (95%, 111mg, 1.78 mmol) were added. The reaction was stirred at 22° C. for 18 hr, filtered and the residue washed with more methanol. The combined organic fractions were concentrated. The residue was redissolved in ethyl acetate and washed with aqueous potassium carbonate, water and brine. After drying (MgSO 4 ) and concentration, the crude (0.47 g) was chromatographed (silica gel, hexane/ethyl acetate 8/2) to give pure 44 (410 mg, 94%). 1 H NMR (CDCl 3 ) 7.50 (m, 2H), 7.37 (m, 3H), 5.58 (s, 1H), 4.43 (dd, J=11, 5 Hz, 1H), 3.68 (dd, J=11, 10 Hz, 1H), 3.59 (t, J=9 Hz, 1H), 3.45 (dd, J=10, 9 Hz, 1H), 3.38 (td, J=10, 5 Hz, 1H), 3.07 (dd, J=12, 5 Hz, 1H), 2.53 (dt, J=13, 8 Hz, 1H), 2.41 (ddd, J=10, 9, 5 Hz, 1H), 2.30 (dt, J=13, 7 Hz, 1H), 2.17 (dd, J=12, 10 Hz, 1H), 1.39 (m, 2H), 1.28 (m, 2H), 0.92 (t, J=7 Hz, 3H).
EXAMPLE 42
2,3 diamino-1,5-(butylimino)-1,2,3,5-tetradeoxy-4,6-O-(R-phenylmethylene)-D-glucitol(45)
To a solution of 44 (385 mg, 1.08 mmol) in methanol (25 ml) in a Parr hydrogenation flask, 10% Pd on C (60 mg) was added. The system was sealed, purged with nitrogen (5 times) and hydrogen (5 times) and then pressurized to 5 psi hydrogen. After running the reaction on a shaker for 3.5 hr, the system was vented, purged with nitrogen and filtered. The filtrate was concentrated and the crude (320 mg) was chromatographed (silica gel, ethyl acetate/methanol/ammonium hydroxide 50/50/2.5) to give 45 (240 mg, 73%). Anal calcd. for C 17 H 27 N 3 O 2 0.25H 20 , C, 65.88, H, 8.94, N, 13.56 Found C, 65.53, H, 8.99, N, 13.28.
EXAMPLE 43
2,3-diamino-1,5-(butylimino)-1,2,3,5-tetradeoxy-D-glucitol(46)
A solution of 45 (235 mg, 0.77 mmol) in trifluoroacetic acid/water (4/1, 10 ml) was stirred at 22° C. for 18 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/methanol/ammonium hydroxide 25/75/3), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give crude 46 (152 mg) which was rechromatographed (silica gel, ethyl acetate/methanol/ammonium hydroxide 25/75/3) to give pure 46 (72 mg, 43%). Anal calcd. for C 10 H 23 N 3 O 2 , C, 55.27, H, 10.67, N, 19.34 Found C, 54.86, H, 10.78, N, 19.00.
EXAMPLE 44
Synthesis of 1,3,5-trideoxy-3-[{2-(dimethylamino)ethyl}amino]-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-altritol (47)
A solution of epoxide 5 (734 mg, 2 mmol) in N,N-dimethylaminoethylamine (7 ml) was heated at 100° C. for 24 hr. Part of the solvent was removed under reduced pressure and the crude residue was chromatographed (silica gel, methylene chloride/methanol/ammonium hydroxide 90/10/1) to give pure 47 (700 mg, 76%) as an oil. Anal calcd. for C 25 H 33 N 3 O 5 , C, 65.91, H, 7.30, N, 9.22 Found C, 65.65, H, 7.45, N, 9.02.
EXAMPLE 45
Synthesis of 3-(butylamino)-1,3,5-trideoxy-1,5-[{(phenylmethoxy)carbonyl}imino]-4,6-O-(R-phenylmethylene)-D-altritol (48)
A solution of epoxide 5 (200 mg, 0.55 mmol) in butylamine (4 ml) was refluxed for 24 hr. Part of the solvent was removed under reduced pressure and the crude residue was chromatographed (silica gel, hexane/ethyl acetate 70/30) to give pure 48 (117 mg, 70%). mp 104°-6° C., Anal calcd. for C 25 H 32 N 2 O 5 , C, 68.16, H, 7.32, N, 6.36 Found C, 68.04, H, 7.39, N, 6.34.
EXAMPLE 46
Synthesis of 1,3,5-trideoxy-3-[{2-(dimethylamino)ethyl}amino]-1,5-imino-4,6-O-(R-phenylmethylene)-D-altritol (49)
To a solution of 47 (1.78 g, 3.9 mmol) in ethanol (35 ml) in a Parr hydrogenation flask, 4% Pd on C (250 mg) was added. The system was sealed, purged with nitrogen (5 times) and hydrogen (5 times) and then pressurized to 5 psi hydrogen. After running the reaction on a shaker for 5 hr, the system was vented, purged with nitrogen and filtered. The filtrate was concentrated and the crude was crystallized from cyclohexane to give 49 (1.14 g, 91%). mp 100°-2° C., Anal calcd. for C 17 H 27 N 3 O 3 , C, 63.53, H, 8.47, N, 13.07 Found C, 63.28, H, 8.59, N, 12.85.
EXAMPLE 47
Synthesis of 3-[{(2-(dimethylamino)ethyl}amino]-1,3,5-trideoxy-1,5-imino-D-altritol (50)
A solution of 49 (600 mg, 1.8 mmol) in trifluoroacetic acid/water (4/1, 6 ml) was stirred at 25° C. for 25 hr. The solvent was removed under reduced pressure and the residue was passed through an ion-exchange column [Amberlite, IRA-400 (OH)] prewashed with distilled water until neutral. The basic fractions, as also followed by TLC (silica gel, ethyl acetate/methanol/ammonium hydroxide 25/75/3), were pooled and concentrated. The water in the fractions was azeotropically removed with toluene to give 50 (250 mg, 72%) which was recrystallized from methanol. mp 120°-22° C., Anal calcd. for C 10 H 23 N 3 O 3 , C, 51.47, H, 9.93, N, 18.00 Found C, 51.61, H, 9.72, N, 17.81.
EXAMPLE 48
Various illustrative compounds synthesized above were tested for inhibition of visna virus in vitro in a plaque reduction assay (Method A) or for inhibition of HIV-1 in a test which measured reduction of cytopathogenic effect in virus-infected synctium-sensitive Leu-3a-positive CEM cells grown in tissue culture (Method B) as follows:
Method A
Cell and Virus Propagation
Sheep choroid plexus (SCP) cells were obtained from American Type Culture Collection (ATCC) catalogue number CRL 1700 and were routinely passaged in vitro in Dulbecco's Modified Eagles (DME) medium supplemented with 20% fetal bovine serum (FBS). SCP cells were passaged once per week at a 1:2 or 1:3 split ratio. Visna was titrated by plaque assay in six-well plates. Virus pools were stored at -70° C.
Plaque Reduction Assay
SCP cells were cultured in 6-well plates to confluence. Wells were washed two times with serum free Minimal Essential Medium (MEM) to remove FBS. 0.2 ml of virus was added per well in MEM supplemented with 4 mM glutamine and gentamycin. After 1 hour adsorption, the virus was aspirated from each well. The appropriate concentration of each compound in 5 ml of Medium 199 (M-199) supplemented with 2% lamb serum, 4 mM glutamine, 0.5% agarose and gentamycin was added to each well. Cultures were incubated at 37° C. in a humidified 5% CO 2 incubator for 3-4 weeks. To terminate the test; cultures were fixed in 10% formalin, the agar removed, the monolayers stained with 1% crystal violet and plaques counted. Each compound concentration was run in triplicate. Control wells (without virus) were observed for toxicity of compounds at the termination of each test and graded morphologically from 0 to 4. 0 is no toxicity observed while 4 is total lysing of the cell monolayer.
96 Well Plate Assay
The 96 well plate assay was performed similarly to the plaque assay above with modifications. SCP cells were seeded at 1×10 4 cells per well in 0.1 ml DME medium. When confluent, the wells were washed with serum free MEM and 25 μl of virus added in M-199 supplemented with 2% lamb serum. After 1 hour, 75 μL of medium containing test compound was added to each well containing virus. After 2-3 weeks incubation the cytopathic effect of the virus was determined by staining with a vital stain. Cell viability was measured by determining stain density using a 96 well plate reader.
Control wells without virus were completed to determine the toxicity of compounds.
Method B
Tissue culture plates were incubated at 37° C. in a humidified, 5% CO 2 atmosphere and observed microscopically for toxicity and/or cytopathogenic effect (CPE). At 1 hour prior to infection each test article was prepared from the frozen stock, and a 20 μl volume of each dilution (prepared as a 10×concentration) was added to the appropriate wells of both infected and uninfected cells.
On the 9th day post-infection, the cells in each well were resuspended and a 100 μl sample of each cell suspension was removed for use in an MTT assay. A 20 μl volume of a 5 mg/ml solution of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was added to each 100 μl cell suspension, and the cells were incubated at 37° C. in 5% CO 2 for 4 hours. During this incubation MTT is metabolically reduced by living cells, resulting in the production of a colored formazan product. A 100 μl volume of a solution of 10% sodium dodecyl sulfate in 0.01N hydrochloric acid was added to each sample, and the samples were incubated overnight. The absorbance at 590 nm was determined for each sample using a Molecular Devices V max microplate reader. This assay detects drug-induced suppression of viral CPE, as well as drug cytotoxicity, by measuring the generation of MTT-formazan by surviving cells.
Assays were done in 96-well tissue culture plates. CEM cells were treated with polybrene at a concentration of 2 μg/ml, and an 80 μl volume of cells (1×10 4 cells) was dispensed into each well. A 100 μl volume of each test article dilution (prepared as a 2×concentration) was added to 5 wells of cells, and the cells were incubated at 37° C. for 1 hour. A frozen culture of HIV-1, strain HTVL-III B , was diluted in culture medium to a concentration of 5×10 4 TCID 50 per ml, and a 20 μl volume (containing 10 3 TCID 50 of virus) was added to 3 of the wells for each test article concentration. This resulted in a multiplicity of infection of 0.1 for the HIV-1 infected samples. A 20 μl volume of normal culture medium was added to the remaining wells to allow evaluation of cytotoxicity. Each plate contained 6 wells of untreated, uninfected, cell control samples and 6 wells of untreated, infected, virus control samples.
Tables 2-6, below, set forth the results of the assay for illustrative compounds prepared in the foregoing Examples in Method A: These results are stated in terms of % Plaque Reduction (mM concentration).
TABLE 2______________________________________Anti-Viral Activity of 2-Azido Analogs ##STR9## VisnaCompound R % Plaque Redn (Conc)______________________________________12 H 76 (0.1 mM)13 n-Bu 78 (0.1 mM)14 CH.sub.2 CH(Et).sub.2 67 (0.1 mM)15 (CH.sub.2).sub.3 CF.sub.3 41 (1 mM)______________________________________
TABLE 3______________________________________Anti-Viral Activity of 2-Amino Analogs ##STR10## VisnaCompound R % Plaque Redn (Conc)______________________________________20 H 91 (0.1 mM)21 n-Bu 66 (0.1 mM)22 CH.sub.2 CH(Et).sub.2 >1 mm23 (CH.sub.2).sub.3 CF.sub.3 9 (1 mM)______________________________________
TABLE 4______________________________________Anti-Viral Activity of 2-Substituted Analogs ##STR11## VisnaCompound X.sub.1 % Plaque Redn (Conc)______________________________________13 N.sub.3 78 (0.1 mM)21 NH.sub.2 66 (0.1 mM)28 NMe.sub.2 41 (0.1 mM)29 NHMe 25 (0.1 mM)30 NHCOPr 20 (0.1 mM)31 NHCOPr 29 (0.1 mM) (Per Butyr)______________________________________
TABLE 5______________________________________Anti-Viral Activity of C-2 & C-3 Substituted Analogs ##STR12## VisnaCompound X.sub.1, X.sub.2 % Plaque Redn (Conc)______________________________________37 (R = H) X.sub.1 = OH, X.sub.2 = NH.sub.2 30 (1 mM)46 (R = Bu) X.sub.1 = X.sub.2 = NH.sub.2 3 (1 mM)______________________________________
TABLE 6______________________________________Anti-Viral Activity of 3-amino Analog ##STR13## VisnaCompound % Plaque Redn (Conc)______________________________________50 38 (1 mM)______________________________________
Compound (50) also effectively inhibited both α- and β-glucosidase enzymes 2% at 1 mM concentration as determined in conventional assays for these enzymes described in U.S. Pat. No. 4,973,602.
The antiviral agents described herein can be used for administration to a mammalian host infected with a virus, e.g. visna virus or in vitro to the human immunodeficiency virus, by conventional means, preferably in formulations with pharmaceutically acceptable diluents and carriers. These agents can be used in the free amine form or in their salt form. Pharmaceutically acceptable salt derivatives are illustrated, for example, by the HCl salt. The amount of the active agent to be administered must be an effective amount, that is, an amount which is medically beneficial but does not present toxic effects which overweigh the advantages which accompany its use. It would be expected that the adult human dosage would normally range upward from about one milligram of the active compound. The preferable route of administration is orally in the form of capsules, tablets, syrups, elixirs and the like, although parenteral administration also can be used. Suitable formulations of the active compound in pharmaceutically acceptable diluents and carriers in therapeutic dosage form can be prepared by reference to general texts in the field such as, for example, Remington's Pharmaceutical Sciences, Ed. Arthur Osol, 16th ed., 1980, Mack Publishing Co., Easton, Pa.
Various other examples will be apparent to the person skilled in the art after reading the present disclosure without departing from the spirit and scope of the invention. It is intended that all such other examples be included within the scope of the appended claims.
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Novel derivatives of 1-deoxynojirimycin are disclosed which have amino or azido substituents at C-2 and/or C-3. These compounds are useful inhibitors of lentiviruses. Methods of chemical synthesis of these derivatives and intermediates therefor are also disclosed.
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This application is a division of application Ser. No. 09/165,258 filed Oct. 1, 1998.
FIELD OF THE INVENTION
The present invention relates to a load limiting device for use in a vehicle with a seat belt.
BACKGROUND OF THE INVENTION
Modern seat belts comprise a length of webbing arranged to pass diagonally across the torso of a vehicle occupant and generally horizontally across the hip region of the vehicle occupant (the so-called lap portion of the belt). This is known as a three point belt system. One end of the belt webbing is firmly attached to a structural part of the vehicle, such as the floor, and the other end is attached to the spool of a retractor which itself is firmly attached to a structural part of the vehicle, usually the side B-pillar. The retractor automatically keeps any slack in the belt wound onto the spool and thus keeps tension in the belt. Between the retractor and the other fixed point, a fastening element such as a metal tongue is fixed to the belt webbing with which it can be fastened into a buckle which itself is attached to a fixed part of the vehicle on the other side of the vehicle seat.
A clock spring in the retractor allows pay out of webbing under the influence of relatively gentle forwardly directed inertia of the vehicle occupant, for example to allow for normal movement of the vehicle occupant such as reaching forward to activate in-car controls, glove compartments or door pockets.
In the event of a crash, the sudden high forward momentum of the vehicle occupant activates a crash sensor which locks the spool against rotation and prevents forward motion of the vehicle occupant to prevent him colliding with the internal fixtures of the vehicle such as the steering wheel, dashboard or windscreen.
However, it has been found in high velocity crashes that the sudden locking of the seat belt can itself cause injury to the vehicle occupant due to the sudden impact of the torso with the belt webbing.
In recent years it has been proposed to introduce a load limiting effect into the seat belt system so as to allow a limited and controlled forward motion of the vehicle occupant after the retractor has locked. This decreases the forces exerted by the belt on the vehicle occupant's torso.
DISCUSSION OF PRIOR ART
Load limiting proposals are described in EP 0297537 wherein a plastically deformable member is used in the retractor, and particularly between the spool and innermost winding of the belt webbing. Alternative load limiting proposals are known in which crushable bushings or nuts or deformable torsion bars are placed in the retractor in the force path between the spool locking mechanism and belt webbing. These proposals are complex and expensive and require the retractor to be specially designed and constructed to incorporate them.
Another proposal is described in EP 715997 in which a slotted metal plate is fixed to a seat belt anchorage point and the retractor is fixed to the plate so that, under load, it slides on the plate deforming the metal and dissipating energy. However, this requires expensive modifications to the retractor.
The present invention proposes improved, simpler and more cost effective load limiting arrangements for seat belts.
SUMMARY OF THE INVENTION
According to the present invention there is provided a load limiting device for use with a safety restraint having seat belt webbing connected to fixed parts of the vehicle and a buckle for fastening at least one point of the webbing to the vehicle, wherein the tension reducing device comprises a metal member associated with the safety restraint, and means for deforming the metal member, the deforming means being arranged to transfer load from the seat belt to the metal member.
Preferably one end of a metal strip is attached to a mounting anchorage for the buckle fastening of the seat belt. Alternatively, one end of the metal strip may be attached to a retractor mounting anchorage of the seat belt. Holes could be made to attach webbing.
According to one embodiment, a metal strip is a substantially planar member which is connected between a belt webbing anchorage and belt webbing and the deforming means comprises an accurate slot through which the metal strip is drawn, i.e. pulled or pushed to deform it into a curved shape when subjected to extreme forces. Alternatively, a bent piece of metal plate may be pulled through a substantially planar guide block so that the bent plate is bent into a substantially flat plate.
According to a second embodiment, a metal strip comprises cut-outs so as to form generally, a ladder shape with rungs, and the deforming means comprises a member engaging in the cut-outs of the metal strip to break or cut the rungs as it moves along the ladder under load. This embodiment may be incorporated into the buckle mechanism such that the tongue is formed in such a ladder shape and the buckle latch forms the deforming means.
According to a third embodiment, a metal strip may be deformed by a cam rotated by action of the protraction of the seat belt under extreme forces. The cam may be mounted to rotate with the retractor web-winding spool, for example attached to the spindle or shaft of the retractor spool. Alternatively, it may be attached at any point in the belt webbing force path such as to a winding axis of a member around which a length of webbing is wound.
In a fourth embodiment, a metal strip has one end attached to the spindle of a winding spool or bobbin, (which may be the retractor bobbin or may be another bobbin attached in the force path of the seat belt to rotate as the belt is withdrawn). As webbing is extracted under force the rotation of the bobbin causes the metal strip, preferably formed of steel, to be wound around the spindle of the bobbin.
According to another embodiment, a metal strip may be deformed by action of a roller pulled over the metal strip, or alternatively by means of a slider.
In a variation of this invention, two coaxially mounted tubes are arranged such that one is fixed to a mounting point of the seat belt and the other is subjected to forces on the seat belt and when one moves relative to the other under action of forces on the seat belt, one or the other is deformed, for example by means of a peg attached to one of the tubes and preferably a performed starter indentation in the other.
The metal member may be in a saddle shape, for example attached to a height adjuster such than an excessive load on the webbing causes the saddle to deform or causes the saddle to deform another part, for example the back of the frame of the height adjuster. This could also be done using a roller on the loop attached to the webbing in a height adjuster. Under normal conditions this roller would fit and slide easily in a groove and cutout in the back plate but under excessive load it will ride past the length of the groove and deform part of the back plate.
Alternatively, the deforming means may comprise rotating members with fins that deform a metal plate as it is pulled past the fins. Rotating wheels comprising fins could be mounted on both faces of the metal plate, or on one face with, for example, a toothed rack against the other face to form mandrel for bending the metal. Preferably the metal strip straightens out again after it has passed the deforming means in this embodiment.
The fins could instead comprise hole punching members. Again a mandrel, either in the form of a rotating wheel with holes corresponding in size and position to the punching member, or in the form of a rack with corresponding holes, will be provided.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the present invention, and to show how the same may be carried into effect, reference be made to the accompanying drawings.
FIG. 1 is a perspective view of a first embodiment of the invention.
FIGS. 2 and 3 are perspective and side elevation views, respectively, of a second embodiment of the invention.
FIG. 4 is a top plan view of another embodiment of the invention.
FIGS. 5 and 6 are right side and left side perspective views, respectively, of yet another embodiment of the invention.
FIGS. 7 and 8 illustrate in perspective and in cross-section, respectively, a further embodiment of the invention.
FIG. 9 is a perspective view of another embodiment of the invention.
FIG. 10 is a front plan view of the embodiment of FIG. 9.
FIGS. 10a and 10b show respective cross-sections of the embodiment of FIGS. 9 and 10.
FIG. 11 is a perspective view of another embodiment of the invention.
FIG. 12 is a front plan view of the embodiment of FIG. 11.
FIGS. 12a and 12b are respective cross-sections of the embodiment of FIGS. 11 and 12.
FIG. 13 is a perspective view of yet another embodiment of invention.
FIGS. 14A and 14B illustrate in rear elevation and side view, respectively, another embodiment of the invention.
FIGS. 15 and 16 illustrate in perspective and in side elevation cross-section, respectively, another embodiment of the invention.
FIGS. 17 and 18 illustrate in perspective and in side elevation cross-section, respectively, another embodiment of the invention.
FIGS. 19 and 20 illustrate in perspective and in side elevation cross-section, respectively, another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a first embodiment of the invention in which a metal member in the form of a generally planar metal strip 1 is pulled through a die 2 which has a curved slot 3 to absorb energy of a safety belt system under high loads. Either the strip 1 or die 2 is attached to a fixed anchorage position on the vehicle. This may be at the buckle end or at the retractor end or at the sill mounting end of a standard three point seat belt. The other is attached to belt webbing or to a buckle or retractor mounting. As the strip 1 is pulled through the curved slot 3 in the die, the metal strip 1 deforms into the curved shape indicated at 5.
The embodiment is particularly easy and cheap to integrate into a vehicle. The flat metal strip 1 can easily be hidden under a seat or in other discrete places in the vehicle. Any combination of shapes is possible. It is not necessary to have a flat metal strip deformed into a curved shape: the opposite would work just as well.
For example, in the embodiment of FIGS. 2 and 3 a bent metal strip 1, attached to a fixed anchorage point of the vehicle via block 6, is pulled through straightening guide blocks 7 in the direction indicated by the arrows A. The guide blocks 7 flatten out the curves in metal strip 1 thus absorbing some of the energy of the system. The upper end of metal strip 1 is attached to seat belt webbing 8.
In the embodiment of FIG. 4 a buckle tongue plate 10 performs the load limiting function. The buckle tongue plate 10 is a metal strip having a series of cutouts 11 that leave cross beams 12 in a form of ladder structure. The tongue plate 10 is inserted into a buckle head 14 so as to secure the safety belt around the vehicle occupant. Within the housing of the buckle head 14 is a latch member (not shown) which engages into a first cut out 11a on the tongue plate 10 and, under normal use, is retained in the first cut-out 11a by virtue of the lateral bar 12a. Under conditions of extreme load, a first lateral bar 12a will break thus absorbing some of the energy. A second lateral bar 12b will also break if the load applied to it is high enough, i.e. if enough energy has not already been absorbed by the first lateral bar 12a breaking. However, a third lateral bar 13 is constructed to be stronger than the first and second bars 12a and 12b. The third lateral bar may be made of a different, stronger material or may be made of different dimensions to make it stronger. It is, of course, imperative that the last bar 13 does not break, even under conditions of extremely high load so that the vehicle occupant is safely restrained. Preferably some form of plastic coating or similar arrangement is put over the cut-outs 11b and 11c to ensure that the buckle does not falsely engage in these cut-outs in normal use since this would limit the load limiting effect.
FIGS. 5 and 6 illustrate another embodiment of the invention. Seat belt webbing 8 is wound around a spool 15 that is mounted for rotation in a frame 16 on a spindle 17. Mounted on the spindle 17 on one side of the frame 16 is a bobbin 18. A metal strip 1 passes through a strip guide 19, which is a die, and is fixed to the outer periphery of the bobbin 18. Under conditions of high load, the belt webbing 8 is pulled in the direction indicated by arrow A, causing the spool 15 to rotate in a counter-clockwise direction. This in turn, rotates the spindle 17 and thus the bobbin 18 and the metal strip 1 is wound onto the bobbin 18 is an anti-clockwise direction. This absorbs some of the peak energy of a crash; i.e. it flattens out the crash pulse and reduces the possibility of injury to the vehicle occupant.
The spool 15 may be part of a retractor or alternatively may be an independent spool mounted at another point in the seat belt system. It could be mounted via its frame 16, to the buckle anchorage point or to the sill via mounting hole 20.
FIGS. 7 and 8 illustrate another embodiment of the invention wherein seat belt webbing 8 is connected to a metal loop 21 which is integrally connected to an outer tube 22. An inner tube 23 is connected via a hole 25 in a plate 24 to an anchorage point of the vehicle (not shown). The two tubes 22 and 23 are fit together tightly, but can slide relative to each other. A peg 26 is fixed to the outside tube and projects into the surface of the inside tube. At the end of the inside tube 23, a preformed starter indentation 27 is made.
When a load is applied to the webbing 8 in the direction indicated by arrow A, then the outside tube 22 is pulled past the inside tube 23 and the peg 26 deforms the surface of the inside tube 23, thus dissipating energy.
FIGS. 9 and 10 illustrate another embodiment that may be used at a shoulder mounting point or a sill end or indeed at a buckle end wherein it could be easily hidden under a seat. This could thus be used as a webbing buckle or retractor attachment. A frame 30 is mounted to the appropriate anchorage point via mounting hole 31 in a bracket 32 at one end of the frame 30. Seat belt webbing 8 is attached to a loop or ring 33 that is held in the fork of a saddle 34. This saddle 34 sits in a slot in the frame 30 in normal use. Retaining stops or pins 35 are located at both ends of the frame 30 to prevent the webbing 8 being pulled completely out of the anchorage. Under high loads on the webbing 8 the loop 33 exerts a high force on the saddle 34 which slides in the slot 39 in the frame 30 and at the end of the slot 39 in the frame 30 and at the end of the slot 39 will deform the back plate of the frame 30 In the cross-sectional views of FIGS. 10, 10a and 10b, like numerals are used for like parts.
FIGS. 11 and 12 illustrate a similar embodiment to FIGS. 9 and 10 except that instead of the slide being attached to the saddle 34, a roller 36 is mounted on the lower arm of the loop or ring 33 and is used to deform the back plate of frame 30.
FIG. 13 illustrates another embodiment in which an eccentric cam 40 rotates to bend a metal strip 1. The eccentric cam 40 is mounted to rotate with a roller 41 mounted on a frame 42. The frame 42 is mounted to an anchorage point of the belt or the buckle via mounting holes 43. Attached to and wound around the roller 41 is a cable 44. The other end 45 of the cable 44 is attached to seat belt webbing or to a buckle to take the load exerted on the belt. Under load the cable 44 unwinds from the bobbin 41, rotating the bobbin and thus the eccentric cam, and deflecting and deforming the metal plate 1 (which may be a spring leg of the frame 42).
FIGS. 14A and 14B illustrate another embodiment, in which rotation of a spool 50 (which may be the retractor spool or another bobbin with some webbing wound on it) causes a cutting wheel 51 to rotate, driving teeth 52 into metal strip 1, so as to deform or cut the metal strip 1. The metal strip 1 is mounted on a carriage 53 that moves in the direction of arrow A when the belt webbing 8 is under load. The metal strip 1 can be sheared or split to dissipate energy.
Another embodiment is shown in FIGS. 15 and 16. In this embodiment the metal strip 1 (which is preferably steel) strip 1 is deformed by rotating teeth on a wheel which may be formed by the intermeshing elements of gear wheels. Two gear wheels 66 are mounted one on either face of the metal strip 1 on bearing pins 67 fixed to a mounting frame 68. The mounting frame is fixed to a fixed part of the vehicle via mounting holes 64 (FIG. 16).
The wheels 66 have radically extending arms somewhat in the form of gear teeth and these are arranged to intermesh with each other on either side of the metal strip 1 so as to deform the metal strip into the spaces between the gear teeth on first one and then the other of the gear wheels 66, as shown most clearly in FIG. 16. The metal deforms as it passes between the gear teeth but straightens out as it passes out again and is subject to the full load on the webbing or the buckle attachment at 65. Guide flanges 69 are provided on both sides of each of the gear wheels 66 and these meet as shown at 70 to synchronize the rotation of the gears.
In the embodiment of FIGS. 17 and 18 the metal strip 1 is deformed by a gear wheel 66 against a toothed mandrel (rather than against another rotating gear wheel). Like parts are referenced with like reference numbers. The mandrel 71 has upstanding teeth 72 against which the metal strip will pass. Again, the metal strip 1 is deformed as it passes the gear wheel 66 but straightens out again when subjected to the full force of the pull on the webbing or buckle mounting point at 65. The rack moves as the gear rotates.
In FIGS. 19 and 20 a further development of this concept is shown in which the gear teeth are arranged to punch out holes in the metal strip 1. Again, like parts are referenced accordingly. In this case one of the gear wheel has radically extending punching teeth 73 while the other has radically indented holes 74 to form a punching mandrel for the punching holes 73. Of course, the female punch wheel could be replaced by holed rack that would move along as load limiting progresses.
From the foregoing, it will be apparent to those skilled in the art that modifications may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not intended to be limited except as may be made necessary by the appended claims.
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A load limiting device is used with a vehicle seat belt during a crash to allow a limited and controlled forward motion of a vehicle occupant after the retractor has locked. The load limiting device decreases the forces exerted by the seat belt on the vehicle occupant's torso. The load limiting device has a metal member and means for deforming the metal member associated with the seat belt. Excessive load on the seat belt is transferred to the metal member by deforming the metal member.
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FIELD OF THE INVENTION
[0001] The present invention relates to telecommunication systems. In particular, the invention concerns a method and a system for real-time addition of statistics definitions and for achieving real-time reporting in a telephone switching system.
BACKGROUND OF THE INVENTION
[0002] The operation of telephone networks (e.g. PSTN, Public Switched Telephone Network; PLMN, Public Land Mobile Network; ISDN, Integrated Services Digital Network) is based on telephone switching centers used for the transmission of calls. Therefore, it is of primary importance that the telephone switching centers should work properly. Telephone switching centers are complex systems, so maintaining their operational condition is a challenging task. One of the essential functions of a telephone switching center is to monitor its own operation and maintain statistics about it. However, it is to be noted that the various tasks relating to monitoring and statistics should not hamper the normal operation of the telephone switching system.
[0003] A large amount of data is continuously being collected about the operation of the telephone switching center. The data is collected e.g. by a network management system (NMS). The operation of the telephone switching system is monitored and managed by the network management system. From the data collected by the network management system, various statistics and reports are generated. Reports are generated e.g. about the calls transmitted by the telephone switching center. One of such reports is the Call Detailed Record (CDR) generated from a call. The call detailed record contains various call-specific data, including e.g. the parties to the call, call duration, etc. Reports are generated on the basis of various specifying functions. In this context, the ‘specifying function’ refers to a general denominator used to pick up a desired quantity from among the information collected for statistics. In the case of the call detailed record, this specifying function is called a counter. By using a counter, it is easy to pick up the desired quantities from the mass of information collected for statistics.
[0004] At present, a problem in the statistical and computing functions is that the information to be reported and the reports themselves are subject to changes. There may arise e.g. a situation where it would be desirable to add a new counter to the call detailed record. Currently the amount of work needed to add a single counter to an existing call detailed record is unreasonable.
[0005] Further, at present the network management system cannot be informed in real time as to what information is available from a given network element.
OBJECT OF THE INVENTION
[0006] The object of the present invention is to eliminate the drawbacks referred to above or at least to significantly alleviate them. A specific object of the invention is to disclose a new type of method and system for the addition of statistics definitions in real time and for the achievement of real-time reporting. One of the objects of the invention is to facilitate the addition of new counters to a telephone switching system.
[0007] When a network element is to be expanded by adding e.g. new computer units, the invention makes it possible to obtain real-time data about the information provided by the new computer units.
[0008] As for the features characteristic of the present invention, reference is made to the claims.
BRIEF DESCRIPTION OF THE INVENTION
[0009] The method of the invention concerns the addition of statistics definitions in real time and the achievement of real-time reporting in a telephone switching system. The system of the invention comprises a database which contains information of essential importance to the telephone switching system, and a database manager whose function is to maintain the database. The database manager is e.g. a program block or process implemented using a computer. In addition, the system of the invention comprises one or more service providers whose function is to produce information about the operation of the telephone switching system.
[0010] According to the invention, a registration of a service provider is received by the database manager. When a network element comprised in the telephone switching system is started up, the service provider remains waiting until the database manager gives it a permission to start up. At start-up, the service providers send an inquiry e.g. to a name service to learn the location of the database manager. Thus, the location of the database manager may be unknown to the service providers at start-up. When the network element is started up, the database manager reports to the name service. ‘Name service’ refers to a service implemented using a computer which registers the locations of service providers belonging to the same network element and of different computer units.
[0011] The database manager asks the service provider to give detailed information about the new service. The database manager saves the definition data supplied by the service provider into the database. The information produced by each service provider is associated with individual identification data. The service provider may also give the database manager a reference to a file that contains details about the content of the service produced by the service provider. On the basis of the definition data given by the service provider and/or of existing data, it is possible to generate a new definitions file.
[0012] In an embodiment of the invention, the version number of the service produced by the service provider is first checked. If the version number of the service is so far unknown, then the service provider is asked to give detailed information about the services produced by it. If the version number of the service is already known, then it is possible to send service requests to the service provider and no separate update is needed.
[0013] In an embodiment of the invention, a service request is sent to the service provider. At the same time, the version of the service provided by the service provider is checked on the basis of acknowledgement data received from the service provider and of the version number received with it. If the version number is so far unknown, then the service request is cancelled.
[0014] The database of the invention contains all possible counter data and other necessary data needed for the generation of reports. For each counter and each piece of information, the database contains a number of definition data items. There may be two kinds of definition data: fixed definition data and network-element specific definition data. Fixed definition data means e.g. names obtained from various standards. The counters and different pieces of information are associated with certain fixed data, which have to be input into the database beforehand. Below are a few examples of fixed definition data.
[0015] Id_nro. An unambiguous identification number for each counter. No other counter or piece of information can have the same identification number.
[0016] Name. The name is a generally used designation of the counter. Names are found e.g. in standards.
[0017] Type. Indicates the type of the counter or data in question.
[0018] Report_type. Indicates the type of the report that the counter belongs to. The report is e.g. a traffic measurement or load monitoring report.
[0019] The network-element specific definition data include e.g. data needed by measurement software in order to be able to locate the counter or information in the network element and to add it to the report. The database manager receives these definition data from the service providers. Presented below are a few network-element specific definitions.
[0020] Exist. Indicates whether the counter or piece of information in question exists in the network element concerned or not.
[0021] Shown. If the counter or piece of information exists in the network element, this indicates whether it is to be shown on reports delivered to the client.
[0022] Service. Name of the service providing the counter or service in question.
[0023] Unit_nro. The number of the computer unit in which the provider of the counter or information is located.
[0024] Process_id. Identification of the process providing the service.
[0025] Once the definition data supplied by the service provider have been updated in the database, those and other necessary data can be used as a basis for the generation of new definitions files. The database manager generates a definitions file automatically when necessary. ‘Definitions file’ refers to a file which specifies what data is collected from which unit. It also specifies the form of the report. The measurement programs generate reports on the. basis of a definitions file produced by the database manager. It is possible to produce different reports for different parties. The amount and accuracy of data reported to a given party may be greater than of data reported to another party. Further, it is possible to delete an existing definitions file or change it as desirable.
[0026] There may be one or more databases. Different types of data can be stored in separate databases.
[0027] The system of the invention comprises means for receiving the registration of a service provider by the database manager and means for sending by means of the database manager an inquiry regarding the services produced by the service provider. In addition, the system comprises means for storing the definition data given by the service provider in the database and means for generating a new definitions file on the basis of the definition data given by the service provider and/or of existing information.
[0028] In a preferred embodiment of the present invention, the system comprises means for checking the version number of the service provided by the service provider, means for asking detailed information about the services produced by the service provider, and means for requesting a service from the service provider.
[0029] In a preferred embodiment of the present invention, the system comprises means for requesting a service from the service provider, means for checking the version number of the service produced by the service provider and means for canceling the service request.
[0030] In a preferred embodiment of the present invention, system comprises means for reporting the database manager to a name service. The system further comprises means for establishing the address data of the database manager via an inquiry to the name service.
[0031] In a preferred embodiment of the present invention, system comprises means for attaching individual identification data to the information produced by the service provider. The system further comprises means for dividing the definition data into fixed definition data and network-element specific data.
[0032] In a preferred embodiment of the present invention, system comprises means for giving a reference to a file to the database manager, said file containing information about the content of the service produced by the service provider, and means for storing the data collected by the database manager in several databases on the basis of data types.
[0033] In a preferred embodiment of the present invention, the system comprises means for generating definitions files on the basis of the data contained in the database, and means for generating a report on the basis of a definitions file generated by the database manager.
[0034] In a preferred embodiment of the present invention, system comprises means for deleting or changing a previously defined definitions file.
[0035] The present invention makes it possible to add new features or counters to the statistical functions and reporting. An existing implementation need not be changed when new counters are to be added to the reports or when existing ones are to be deleted. Moreover, the invention makes it possible to transfer the same program code produced for measurement functions from one network element to another. When a network element is expanded e.g. by adding new computer units, the invention allows real-time data to be obtained about the information provided by the new computer units. All the available network-element specific information is provided in the database of the invention. That is where e.g. the network management system can get the information it wants.
[0036] Furthermore, the invention eliminates hard-coded reports and allows very dynamic reports to be generated.
LIST OF ILLUSTRATIONS
[0037] In the following, the invention will be described in detail by the aid of a few examples of its embodiments, wherein
[0038] [0038]FIG. 1 presents a preferred system according to the invention, and
[0039] [0039]FIG. 2 presents a preferred example of the operation of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0040] [0040]FIG. 1 presents a preferred system according to the present invention. The system presented in FIG. 1 comprises a telephone network PSTN and network elements LE 1 and LE 2 . Connected to both network elements is a network management system NMS. Moreover, both network elements are connected to the telephone network PSTN. The network element is preferably a telephone switching center, e.g. a DX200 manufactured by the applicant. It is to be noted that the system in FIG. 2 is only presented by way of example and may be a part of a larger system.
[0041] The telephone switching centers LE 1 and LE 2 comprise a bus BUS with several different computer units connected to it. Such units are e.g. computer units a and b. There is no predefined limit to the total number of computer units. In this example, the telephone switching center contains n computer units.
[0042] The network management system NMS is connected to the telephone switching centers LE 1 and LE 2 e.g. via an X.25 packet service. Via the network management system, it is possible e.g. to produce information about the operation of the switching center, analyze the traffic and perform various management operations.
[0043] [0043]FIG. 2 presents a preferred example of the operation of the invention. FIG. 2 comprises a service provider SER, a database manager MGER, a database DB, report definitions files RDF and a statistics unit STU, all of which may be located e.g. in the telephone switching center. The service provider communicates with the database manager. Although the figure only shows one service provider, the operation is not limited to a single service provider; instead, the system may comprise several service providers. The database manager is responsible for the updating of the database with the information received from the service provider. The database manager is equipped with means for generating definitions files on the basis of the contents of the database. From the information in these definitions files, the statistics unit can generate the required reports. ‘Statistics unit’ may refer to any computer unit in the network element.
[0044] Using program block or process 9 , the address data of the database manager MGER is established via an inquiry to a name service. Via program block or process 10 , individual identification data is attached to the information produced by the service provider SER, and notification means 12 are used to give the database manager a reference to a file that contains information about the content of the services produced by the service provider.
[0045] The database manager MGER comprises reception means 1 for receiving the registration of the service provider SER and data acquisition means 2 for asking for information regarding the services produced by the service provider. Using program block or process 4 , a new report definitions file RDF is generated on the basis of information supplied by the service provider or providers and/or existing information. Using checking means 5 , the version number of the service produced by the service provider is checked, and functional means 6 are used to send a service request to the service provider. Using means 7 , a service request already sent can be canceled.
[0046] Using program block or process 8 , the database manager MGER is reported to the name service, storage means 13 are used to store the information collected from the service providers SER in several databases on the basis of data types, and generating means 14 are used to generate report definitions files RDF based on the information contained in the database DB. Processing means 16 are used to delete or change a previously defined definitions file.
[0047] The database DB comprises storage means 3 , which are used to store the definition data supplied by the service provider SER in the database and sorting means 11 for dividing the definition data into fixed definition data and network-element specific data. The statistics unit STU comprises means 15 for generating a report. The report is generated on the basis of a report definitions file RDF produced by the database manager MGER.
[0048] At the start-up of the network element, the database manager MGER reports to the name service. ‘Name service’ means a service, implemented e.g. using a computer, which registers the locations of service providers and different computer units belonging to the same network element. The database manager has to be thus registered with the name service to make it possible for processes needing the services of the database manager to establish its location. Further, as the network element is started up, the service provider SER remains waiting until the database manager gives it a permission to start up. The operation is not limited to a single service provider; instead, several of them may be included in the system.
[0049] When started up, the service providers SER report to the name service and ask it for the location data of the database manager MGER. Based on the location data, the service providers locate the database manager and report to it, arrow 17 a. Thus, the location of the database manager may be unknown to the service providers at start-up time. The database manager collects information about the service providers and starts a round of inquiries. Taking a service at a time, the database manager inquires what counters/information are/is provided in the service, arrows 17 b and 17 c. Such data include e.g. identification number, name, type and report type data. The identification number is counter-specific, so no other counter or information can have the same identification number. The name is the designation generally used to refer to the counter in question. The type indicates what type of counter or information is provided. The report type data indicates the type of report the counter belongs to. Report types include e.g. traffic measurement and load monitoring.
[0050] Having collected all the necessary information about the service providers SER and the services provided by them, the database manager MGER updates the database DB with the information it has collected, arrow 18 a. The database manager MGER reads the definition data in the database as indicated by arrow 18 b and generates the actual report definitions files RDF, arrow 19 a. A measuring unit, which in this example is a statistics unit STU, uses the report definitions files RDF to generate the required reports, arrow 19 b. The operator can define e.g. the reporting frequency and the numbers of samples. The statistics unit STU generates the report on the basis of the definitions file as indicated by arrow 19 c. It is to be noted that when referring to a statistics unit STU, this is only a preferred example of a computer applicable for the purpose.
[0051] Means 1 - 16 are implemented e.g. as software blocks using a computer.
[0052] In an embodiment as illustrated in FIG. 2, when a service requester needs a service, it can first check the version number of the service provided, if desirable. If the version number of the service is previously known, then the service requester can set a service request to the service provider. If the version number is unknown, then the service requester will ask the service provider to supply information about the service in question. The service requester is e.g. a database manager as shown in FIG. 2.
[0053] In another embodiment according to FIG. 2, the service requester requests a service from the service provider directly without first checking the version number. In a response message, the service provider sends the version number of the service. If the version number received is unknown to the service requester, then the latter will cancel the service. The service requester is e.g. a database manager as shown in FIG. 2.
[0054] The invention is not restricted to the examples of its embodiments described above; instead, many variations are possible within the scope of the inventive idea defined in the claims.
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The invention concerns a method and a system for real-time addition of statistics definitions and for achieving real-time reporting in a telephone switching system, comprising a database containing information of essential importance to the telephone switching system; a database manager whose function is to maintain the database; and one or more service providers. In the method, a registration of the service provider is received by the database manager; the service provider is asked by means of the database manager to supply information about the services.
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BACKGROUND OF THE INVENTION
[0001] The present invention relates to an improved process and apparatus for pretreating fresh food products or produce prior to packaging or further and final processing. Most fresh fruits and vegetables are grown outside and exposed to considerable variances in environmental factors of light, temperature, humidity, moisture, and nutrient levels. When these factors combine resulting in accelerated growth conditions, high internal (turgor) pressures occur in the fruit or produce. High internal pressures also commonly occur in fruits and vegetables that are grown in the “forced” growth conditions employed in greenhouse environments.
[0002] Fresh fruit and vegetables, especially those grown under accelerated conditions, develop internal pressures sufficiently high to rupture cellular walls and epidural encasements resulting in interstitial cracks. Once cracks occur they not only have deteriorated cosmetic appearance, but also have released the enzymatic mechanism (Phenoloxidase) that begins the breakdown of the fruit. Additionally, a crack in the epidural layer and the ruptured underlying cells exposes the inner sugars, providing a fertile media for growth of molds, yeasts, and bacteria, which further breakdown the fruit.
[0003] For some products genetic manipulation has been explored to alter the nature of the produce, creating a product with a thicker epidermal layer or skin and more hardy cellular structure. These structural modifications to the plant can create fruit that can better contain the internal pressures until they are reduced by the natural moisture transpiration. The frequent consequence of this genetic manipulation is a product with less desirable flavor profiles and tactile mouth feel.
[0004] This transpiration of moisture for all fruits and vegetables begins upon picking and continues until the fruit or vegetable has either been used, processed or discarded. During the transportation and storage portions of the post harvest process, the transpiration of the product may be accelerated because of the lower humidity conditions resulting from the direct expansion refrigeration units used in these areas. Often the post harvest processing of fresh fruit and vegetables includes the application of oil or wax to seal the surface to slow the rate of moisture loss to extend the shelf life of the product.
[0005] Fruit and vegetables that are picked from the field during normal growing seasons are picked at the temperatures in the growing environment. Typically this is hot, on the order of 80, 90 or even 100+degrees. This product is said to contain “field heat.” Currently there are numerous ways that this heat is dealt with prior to inspection and packaging. These include: a) Let the product “rest” in the packing shed, with or without forced air ventilation, for a period of time generally ranging from several hours to over a day to allow some of the field heat to dissipate; b) Wash the product in cool water; c) Place the product in a forced air cooler; d) Place the product in a vacuum cooler; or e) Forced air evaporative cooling.
[0006] a) “Resting” the product.
It has been shown that prolonged exposure of the product to temperatures over 80° F. accelerates the breakdown of the product, causing it to lose firmness and shorten the shelf life. Additionally, product with high turgor pressures may spontaneously yield to the internal pressures resulting in cracking. This process is often made worse by micro damage occurring to the fruit as the result of the handling and transportation prior to the “resting” phase. Also temperatures in the packing sheds can often exceed 80° F. thereby minimizing the cooling effect and effectiveness of this method.
[0008] b) Hydrocooling or washing the product in cool water.
This is an effective method of dropping the temperature inside the product. Unfortunately when dealing with a product with high turgor pressure, the cooling effect is too rapid to allow the necessary slow conduction of heat to lower the core temperature. The effect of this rapid drop in temperature is that the exterior of the product cools more quickly and, as it cools, it shrinks. The shrinking of the exterior surface increases the internal pressure in the product, resulting in substantially increased incidence of cracking.
[0010] c) Forced Air Cooler or Conditioning Room.
The ultimate effect of this treatment, while potentially slower in effect than washing the product in water, also results in increased incidence of cracking. The existing technology typically produces a cooling effect by passing air across a direct expansion, cooling coil. The surface temperature of the coiling coil, which is determined by the expansion characteristics of the refrigerant, is well below the dew point of the air stream. This results in air with a very low dew point. This cold dry air both cools and dehydrates the product. The high temperature and vapor pressure differentials between the air and the product combine to rapidly shrink the outside layers first, and increase the core pressure within the fruit, resulting in cracking.
[0012] d) Vacuum Cooling.
This is used on certain fruits and vegetables with a high surface to mass ratio, things like lettuce, corn, celery, peppers, etc. For this process the product is put into a chamber and the pressure in the chamber is reduced thereby cooling the product by evaporation. The evaporation loss, which is primarily water, results in about 1% loss in weight for every 10° F. temperature loss. This method can also be combined with the use of refrigeration coils in the chamber. This method is ill advised for product with high internal pressures. As pressure in the chamber is reduced the differential between the pressure within the cells and the atmospheric (external) pressure becomes greater, splitting the fruit that is already at risk.
[0014] e) Forced Air Evaporative Cooling.
An alternative method for cooling products is the use of forced air through a cascade of falling water droplets or a mist spray. This method of cooling the product is often used because the equipment is much less expensive. The air is cooled by the releasing of its heat to the latent heat of vaporization of the moisture droplets. The air exits the cooler unit with a high relative humidity. Depending upon the humidity of the air stream, the product may be slightly cooled (on the order of about 10° F.) but at best little has been done to relieve the internal pressure. In most cases, the internal pressure is increased, which results in increased cracking.
[0016] The present invention seeks to safely and slowly relieve the internal cell pressure, while also adjusting the product to the desired processing temperature. This preprocessing of the produce is most effective when employed as quickly as possible after the harvest and before the cracks have formed. This effectively salvages fruit or vegetables that would otherwise be separated and discarded as waste. The producer is able to retain a greater portion of the product as saleable, than currently is possible.
[0017] A principle underlying this present inventive process and apparatus is controlling the temperature and humidity of the air media and then circulating that media to insure intimate contact with the surface of all the fruit or vegetables. The system is designed to separate the latent and sensible heat loads of the product so that the differential driving force can be controlled to remove the excess moisture and still be able to deliver the final desired product temperature. The current state of the art does not allow the separation of these functions. Failure to separate the two heat loads results in imbalance between the humidity and temperature resulting in overly aggressive environmental conditions which will either dehydrate the product too far and/or too quickly, or not allow the desired final product temperature to be attained.
[0018] A measure of the driving force between the recirculated air within the enclosure and the partial pressure of the moisture in the fresh produce is the vapor pressure deficit (VPD). It may be defined as the difference in the pressure exerted by the amount of moisture in the air and how much moisture the air can hold (also referred to as saturation pressure.) The saturation pressure can either be determined from a psychrometric chart or calculated. For the VPD to be calculated the ambient air temperature must be known and either the dew point temperature or the relative humidity must also be known.
[0019] When the temperature of the air and the source of transference are the same or similar, the vapor pressure deficit represents a much simpler and nearly straight-line relationship of the sum of evaporation and transpiration from plants or other measures of evaporation. It proves to be much more useful than merely looking at the relative humidity or grains of moisture per pound of dry air.
[0020] Thus, the vapor pressure deficit is the measure of the difference between how much moisture is in the air and how much it can hold when saturated. Vapor pressure vp air is a measure of how much water in the gaseous state is in the air. More moisture in the air translates to higher vapor pressure. The maximum amount of vapor content in the air for a given temperature occurs when the air is saturated, at the dew point, and is called the saturation vapor pressure or vp sat . The difference between the saturated air vapor pressure and the actual air vapor pressure (vp sat −vp air ) is the definition of the vapor pressure deficit.
[0021] Higher VPD numbers occur at lower humidity levels when the air has a higher capacity (or affinity) for additional moisture. This corresponds to higher rates of water transference from the fresh produce or fruit. Lower VPD numbers occur at high humidity levels, whenever the air is at or near saturation and cannot accept additional moisture. This corresponds to lower rates of water transference from the fresh produce or fruit.
[0022] One method for calculating saturation vapor pressure has been proposed by Jessica J. Prenger and Peter P. Ling in the 2000 Ohio State University Extension Fact Sheet, entitled Greenhouse Condensation Control: Understanding and Using Vapor Pressure Deficit (VPD) AEX-804-01 uses the Arrhenius equation, directly from the temperature. This equation is:
[0000] vp sat =e (A/T+B+CT+DT2+ET3+FlnT)
[0000] This equation can be used to determine the vapor pressure for both the general condition temperature in the enclosure and at the dew point temperature. If the temperature of the air and the temperature of the fruit are significantly different, calculating the vapor pressure at the temperature of the fruit as an approximation may be used to gain insights into the nature of the transference between the fruit, the boundary layer, and the recirculated air.
[0023] The vapor pressure in the air vp air is determined by multiplying the measured relative humidity (RH) times the vp sat . The difference between vp sat and vp air is the calculated value of the vapor pressure deficit (VPD). The converse of that equation that is also useful is that the relative humidity (RH) is equal to (vp air /vp sat ).
[0024] If the air temperature and dew point are measured, the relative humidity can be determined by dividing vp dew by vp sat . Alternatively, the dew point can be determined using a psychrometric chart, well known in the art (see FIG. 12.2 , page 12-5, Perry's Chemical Engineering Handbook, 7 th Edition, by Robert H. Perry and Don W. Gran, New York, McGraw/Hill (1997).)
[0025] The vapor pressures and vapor pressure deficit may also be derived using a modified psychrometric chart, as shown in FIG. 4 , which was prepared using the Arrhenius equation to calculate the saturated vapor pressure (Relative Humidity=100%) for the different temperatures and then using the equation vp air =Relative Humidity X vp sat to calculate the vapor pressures at the different relative humidities along the constant temperature lines.
[0026] Typically, existing analytical instruments may be used to determine the relative humidity and dew point temperatures.
[0027] Adjusting the differential between the partial pressure of the moisture within the produce and the relative humidity in the air media surrounding the product controls the rate of moisture transference between the product and environment. This relieves the turgor pressure without rupturing the cellular structure. The rate of transference is controlled to allow diffusion through the semi-permeable membranes of the cells from the core to the epidural layers of the fruit or vegetable.
[0028] Different products require different transpiration rates to relieve the turgor pressure without drying and shrinking the epidural layers too quickly, and causing cracking. Depending upon the product, the desired VPD is in the range of approx. 0.5 to approx. 3.0 kilopascals. A principal objective of the present inventive system is to provide a means for achieving the desired VPD for any selected product.
[0029] The airflow must insure intimate contact with the surface of the fruit or vegetable. This is accomplished using a high volume of forced air movement around the produce, effectively washing away the surface boundary layer of heat and moisture. Failure to provide a sufficiently high velocity across the fruit or vegetable allows the development of a saturated boundary atmosphere at the food's surface and a retarded migration rate.
[0030] The present invention reduces the specific volume of the moisture within the cells to lower the internal cellular pressure and is capable of removing the field heat of the product. The combined effect of these two desirable outcomes effectively stabilizes the fruit, allowing normal handling with minimized probabilities of further deterioration or cracking.
[0031] The inventive process is terminated whenever the percent moisture loss required to stabilize the produce has been achieved. Dependent upon the nature of the product, the normal percent of moisture loss required is on the order of 0.20% to 2.0%. Normally moisture is transpired from the fruit or vegetable during shipment and storage prior to being consumed or used. But this invention allows the initial portion of that moisture to be removed in a controlled manner before the product at risk has cracked. This results in improved yields and improved finished product quality.
[0032] The beneficial effects of the present inventive process on the treated produce are increased firmness, increased retention of firmness, increased shelf life, reduced damage in transit, and reduced damage during post picking inspection, sorting and packaging. Products that are picked with vine or stem and processed using this invention also have improved attachment retention.
[0033] Internal pressures when present make the produce (fruit or vegetable) more susceptible to damage from micro abrasions and point concentrated impact, which are typical during processing. When excessive internal pressures are present within the fruits or vegetables, these incidental conditions can sufficiently compromise the structural integrity of the containing encasement. When the internal pressures exceed the containment strength of the compromised skin, the produce will pop open (crack).
[0034] Use of the present inventive process and apparatus has no deleterious effect on color, texture, taste, pectins, nutritional values, and volatile flavor components. Because this process is a low temperature process, it may also be used to concentrate the nutritional elements, flavor components, vitamins, and sugars to higher levels than as picked. Since the process is a tightly controlled process for moisture removal, it could be used to dehydrate or dry the product without loss of cell structure or definition.
[0035] The process is well suited for use with fruit and vegetables that are greenhouse, hydroponically, or otherwise grown under environmentally controlled conditions.
[0036] It is also envisioned that the present invention may be applied to field grown produce/vegetables that have been subjected to environmental conditions which resulted in growth spurts. If the internal pressure peaks, the portions of the crops that would be most prone to cracking could be picked. The process could be used to decompress the fruit and allow subsequent ripening to salvage portions of the crop that would otherwise be lost.
SUMMARY OF THE INVENTION
[0037] A primary function of the present invention is to control the differential between the partial pressure of the moisture in the product and the vapor pressure of the humidity in the surrounding air. This is done through the controlled removal of the excess moisture present in the air volume surrounding the produce at the starting environmental conditions and the moisture released from the produce by the transpiration loss induced by the process.
[0038] Another function of the present invention is to control the effect of the temperature on the internal pressure of the produce. If the temperature of the produce is reduced too rapidly, it will result in shrinking of the outer layers faster than the inner layers. The rate of temperature reduction must be sufficiently slow to allow thermal conduction of the heat within the fruit so that the temperature differential between the inner and outer layers of the fruit or vegetable are minimized. The effect of reducing the temperature too quickly is similar to taking a piece of fruit in hand and squeezing it until the internal pressure is increased and the fruit ruptures.
[0039] The inventive process is intended to control the environment and final temperature of the product so that it is above the dew point in subsequent inspection and packaging operations. If the temperature of the produce, when it is presented to subsequent packaging and processing operations, is below the dew point, moisture will condense on the product and could cause the re-absorption of moisture into the product. Moisture that has condensed on the surface of the fruit picks up dirt and juices from the handling equipment. These contaminants foster mold, yeast, and bacterial activity. Processing produce having temperatures below the dew point effectively slows or kills the migration of moisture from within the product, and may result in absorption of additional moisture.
[0040] In its present embodiment, the process utilizes heating (captured waste heat from the process) to increase the temperature of the produce to above the dew point if required. This is important for products that are winter grown (as in greenhouses) or where temperature conditions vary significantly during the course of a picking and packaging day.
[0041] The present inventive system is a closed loop system. Air is forced past the product. This air is contained and run through an axial vane fan, which provides the force to blow the air across the cooling coils to remove the field heat from the product. A separate side air stream is sent to a separate unit to remove the excess moisture from the air stream. The separation of the two sub-processes allows the separation of the latent heat load (removing the moisture) from the sensible heat load (removing the field heat).
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] FIG. 1 is a schematic illustration of the present inventive apparatus.
[0043] FIG. 2 is a more detailed drawing of an embodiment of the present invention showing the tarpaulin cover over the product containers, the dehydrator, recycle heater/cooler, and the return, conditioned air blower.
[0044] FIG. 3 is a schematic drawing showing various sensors used in an alternative embodiment of the present invention.
[0045] FIG. 4 is a Vapor Pressure Value Psychrometric Chart.
DETAILED DESCRIPTION OF THE INVENTION
[0046] The present invention is a process and an apparatus which utilizes controlled atmospheric conditions of an air medium to effect a controlled decompression of the turgor pressure within fruit and vegetables, while simultaneously adjusting (either increasing or decreasing) the temperature of the produce to the optimal conditions required for further inspection, processing or packaging.
[0047] Turning to FIG. 1 , the major components of the system are illustrated. An enclosure 10 , having an internal space 11 , is provided with a product holding station 60 , an exhaust fan 14 , sensible heat removing cooling coils 16 , an air outlet 18 , an air inlet 20 , and a recycle duct 21 . The moisture removal (dehumidification) subsystem includes a dehydrator 22 with a modulating bypass duct 24 with control dampers or valves 26 . The inventive process and apparatus may either add heat with a heating unit 28 or cool the dehydrated air with a cooler 30 . The conditioned air is then directed by a blower 31 from a second end 32 of the recycle duct 21 to the air inlet 20 in the enclosure. The system is a closed loop air circulation system.
[0048] A first sub-system includes the closed loop air circulation system within the enclosure 10 . Conditioned air is forced past the product 12 (usually retained in bins 12 a ) to ensure intimate contact with the surface of the fruit or vegetable to effectively “wash” away the surface boundary layer of concentrated moisture and heat that have been released from the product. This circulation system must also address the air distribution requirements to ensure reasonably uniform delivery of air to and around all the pieces of product 12 .
[0049] Cooling coils 16 are intended to remove only the field heat (sensible heat) from the product. This sub-system is designed to remove the field heat from the product without also removing the latent heat of vaporization for the moisture released from the fruit. The surface temperature of the cooling coils is controlled to prevent the attainment of temperature at or below the dew point of the circulated air. Controlling the temperature of the cooling coils can be accomplished several ways, including:
[0050] 1. Installing a backpressure pressure regulation valve in the refrigerant gas return line in the condensing unit to reduce the pressure drop across the expansion valve;
[0051] 2. Using a thermostatic expansion valve (TXV) with the temperature sensor being located on the surface of the coil; or
[0052] 3. Using a modulating control valve to electronically sense the temperature of the coil and adjust flow of refrigerant through the expansion valve.
[0053] The moisture level of the air stream sweeping over the product as measured by the relative humidity or grains of moisture per pound of air must be controlled. This is done using a slipstream of air withdrawn from the enclosure that is dehumidified and reintroduced into the main circulation air stream.
[0054] The control of the migration of moisture from within the fruit is based upon a “water activity” ratio between the partial pressure of the water vapor in the air surrounding the produce to the vapor pressure of the free water within the fruit. There is a differentiation between the free moisture and what is otherwise bound to the fruit constituents.
[0055] The mass transfer is dependent upon:
[0056] 1. The surface area of the fruit;
[0057] 2. Removal of the boundary layer of the water vapor from the surface;
[0058] 3. Sustained driving force between the inner to the outer subsequent layers of the fruit or vegetable; and
[0059] 4. Sustained driving force between the outer boundary layer of the fruit or vegetable and the surrounding air stream.
[0060] The present inventive process also includes a dehydration sub-system which reduces the moisture levels in the main circulating air stream. The moisture in the main circulating air stream comes for the atmospheric environment in the internal space 11 , and the moisture released from the product 12 . This sub-system involves a slipstream of air removed from the environment and after conditioning is reintroduced into the enclosure and the main circulation air stream.
[0061] The regulation of the humidity of the slipstream may be accomplished a number of ways. These include, but are not necessarily limited to:
[0062] a. Desiccant drying—Control of the humidity of the slipstream is achieved by a modulated splitting of this stream so that all or part of it flows through the desiccant and the remaining portion of the flow is routed around the desiccant unit. These two portions are then recombined and mixed to produce the desired moisture level in the slipstream air. This slipstream subsystem may be either a low-pressure system (operated at pressures on the order of 2″ to 6″ of water column) to a high-pressure system (operating at several pounds per square inch).
[0063] b. Compression, refrigerated drying, and decompression—A portion of the air stream removed is compressed, the moisture is removed using a refrigerated dryer to remove the amount of moisture being generated by the process. The air is then decompressed and reintroduced into the main circulation air stream. Flow to this unit is modulated through the air intake modulated bypass valves and/or starting and stopping of the units.
[0064] c. Cooling, moisture condensation, and reheating—A portion of the air stream is removed and blown across a cooling coil that effective lowers the temperature of the air to a temperature at or below the dew point of the air stream. The temperature of the coil controls the moisture removal. Further modulation can be effected by adjusting the amount of airflow across the coil.
[0065] If a desiccant wheel is used as the means of dehydration, it has the additional benefit of sterilization of the air slipstream. During the regeneration cycle, the temperature of the wheel is heated to between 250 and 350° F. This sterilizes the surface of the wheel. Additionally, the air stream that passes over the regenerated wheel is heated up also. This waste heat may be used to warm the product.
[0066] Whenever the temperature of the produce is low, raising the temperature assists in the reduction of the internal pressure because of the thermal coefficient of expansion. The volume of the fruit gets larger, thereby reducing the pressure within the fruit or vegetable.
[0067] Depending upon the temperature of the produce in the product station 60 , the inventive process either adds heat, if necessary, from external sources such as a heating coil or from utilization of waste heat generated in the latent heat removal system or the dehumidification system, to increase the temperature of the product above the ambient dew point in the production area.
[0068] Various system monitors and controls are provided to measure and adjust the system humidity and temperatures to meet the requirements of the fruit or vegetables being pretreated.
[0069] While the present description illustrates an enclosure 10 , there may be various other environmental containment options. These may include an enclosure or a tunnel(s) with various zones to isolate the process from external conditions which would alter the differential driving forces (temperature and humidity) established between the produce and the process.
[0070] The scope of this invention is such that it may be employed as a 1) batch process; 2) as a continuous transportation process with various chambers of progressively different temperature and humidity environments; or 3) as a mobile trailer mounted process that could be transported to the field or farm to increase the good yield of the product being picked.
[0071] FIGS. 2 and 3 illustrate an embodiment of the apparatus and process of the present invention. The process includes providing an enclosure 10 or containment environment having an internal space 11 wherein the temperature and relative humidity may be controlled. The enclosure is provided with an air inlet 20 and an air outlet 18 and a product station 60 where bins or containers 12 a of fresh fruit or vegetables 12 may be placed in spaced apart rows on either side of an exhaust fan 14 at one end of the enclosure. The rows form an airflow aisle 15 with one open end 17 . A tarp or cover 19 ( FIG. 2 ) is extended over the product station, across the tops of the produce bins 12 a, along the sides of the product bins 12 a, and over the open end 17 to form an air plenum tunnel 23 . The cover 19 has side curtains 51 that may be designed to have varying percentages of open area to allow similar volumes of air to pass, across the product 12 in bins 12 a, and into the plenum tunnel 23 from all bin 12 a positions along the rows, when the exhaust fan 14 is activated. The cover is intended to prevent air short-circuiting either into the tops of the bins or at the ends of the rows. In FIG. 3 , the top portion of the cover 19 is not shown for clarity purposes.
[0072] Sensors and controllers ( FIG. 3 ) measure the following:
[0073] a. Product temperature T—This determines whether the product needs to be heated or cooled during this process to attain the predetermined exit temperature set point. It also serves as an indication of the water activity within the product. Samples are pulled and weighed at various intervals through the pretreatment process to determine the total percentage moisture loss during the process (preferably in the range of 0.20%-2.0%) and also to determine rate of moisture loss. Methods to determine this temperature include destructive insertion of a temperature probe into several randomly selected samples of the produce or non-destructively using a handheld infrared thermometer. In one embodiment of the invention, the product temperature is approximated, when the system is running, by air stream temperature sensor DB 2 . Additional embodiments utilize a series of infrared sensors to even more accurately determine the product temperatures.
[0074] b. Temperature, relative humidity, and dew point within the enclosure are recorded as the starting point and monitored throughout the process via sensor/recorder 52 .
[0075] c. Temperature, relative humidity, and dew point in the production area (not shown) are measured. The production area is where the product will be further processed or packaged. These factors determine the desired final temperature of the product. Normally this will be at the controlled temperature of the production environment, or 5 to 10 degrees above the dew point of the production area.
[0076] d. Humidity sensor 50 located in the air duct 21 is used to sense the humidity of the air slipstream and adjust the modulation of the dehumidifier controls to maintain a desired humidity set point or profile.
[0077] e. Temperature (dry bulb) DB 1 of the volume of air in the enclosure is used to set the minimum temperature differential to be allowed for cooling the product.
[0078] f. Temperature (dry bulb) DB 2 of the air that has passed over the product. This may be used as the set point of the desired final product temperature.
[0079] g. Temperature (dry bulb) DB 3 of the air slipstream that has passed through the dehumidification process and the cooling 30 or heating 28 coils. This is used to control the operation of these coils to either provide a neutral temperature effect from the dehumidification process, or to adjust the rate of further removal or addition of heat to the process.
[0080] Depending upon the structural characteristics of the product, the process of relieving the product turgor pressure using this invention is usually on the order of 1 to 3 hours.
[0081] The operator sets the desired relative humidity to be maintained or, in cases where the temperature of the fruit and the enclosure are significantly different, he may set a relative humidity removal profile, and he sets the final temperature set point or temperature profile to be followed during processing to control the rate and extent of moisture loss from the produce. He then sets the control from sensor DB 2 at the desired final temperature of the product and sensor DB 1 at slightly (approximately 5 degrees) below the desired final temperature, if the product is to be cooled, or slightly above the desired final temperature if the product is to be heated. The exhaust fan 14 is started, which also initiates the refrigeration condensing unit if product cooling is required.
[0082] The temperature of the sensible heat removal cooling coil 16 is adjusted to maintained a coil temperature above the dew point.
[0083] The dehydration unit is set for the desired relative humidity within the enclosure. The temperature and relative humidity sensor 50 for this unit may either be located within the enclosure (as noted in broken lines in FIG. 3 ) or in the air duct 21 from the enclosure 11 .
[0084] The dehydrator 22 and its recirculation fan are started ( FIG. 2 ). The level of dehydration is controlled by modulating the air slipstream to either direct it through the dehydration unit, or to bypass 24 a portion of it around the dehydration unit.
[0085] The process continues until the pre-weighed samples have achieved the desired level of moisture loss required to prevent or reduce product cracking to an acceptable level and the final product temperature is achieved. At this point the exhaust fan 14 and its condensing unit 16 are turned off The dehydrator 22 and its recirculation fan are turned off or switched to a standby mode.
[0086] Finally, the pretreated product is removed from the enclosure and moved to the production area.
[0087] It should be understood that in the current process, if the initial temperature of the product while in the enclosure is below the dew point of the production area, waste heat and/or a heater 28 are used to adjust the temperature of the air in the enclosure to achieve the desired product temperature. If the product needs heat, the enclosure room temperature (DB 1 ) will determine the cutoff point of the heater coil 28 . If the product does not require heat or if the product requires cooling, then the discharge temperature (DB 3 ) is controlled to adjust the cooling coil 30 to match the temperature in the enclosure 11 . If the product requires the removal of field heat, the cooling coils 16 are used to adjust the exhaust temperature of the air reintroduced into the enclosure.
[0088] Two examples are provided to illustrate the process, one shows a condition where the product must be cooled and the second where heat must be added to raise the product temperature.
EXAMPLE 1
[0089] Product start temperature=90° F.
[0090] Enclosure environmental conditions:
Temperature=90° F. Relative Humidity=70% Dew Point=81.4° F.
[0094] Production area environmental conditions:
Temperature=75° F. Dew Point=66° F. Relative Humidity=65%
[0098] Desired Results:
Product temperature above production area dew point of 66° F.; therefore, set target temperature at 72° F. (Range 5°-10° F.) Lower product temperature from 90° F. to 72° F. Optimal processing vapor pressure deficit for selected product=2.0 kpa (Range about 0.5 kpa to about 3.0 kpa)
[0104] Calculations (from FIG. 4 ):
vp sat at 72° F. from FIG. 4 is 2.7 vp air =2.7−2.0=0.7 (target in enclosure) From FIG. 4 , 0.7=25% RH (relative humidity)
[0108] Therefore, the operator would take the following actions:
Set point for removing sensible heat ( FIG. 1 , 2 & 3 —Coil 16 —Temp Sensor DB 1 )=68° F. Cut off temperature (FIG. 3 —Temp Sensor DB 2 )=72° F. Set point for moisture removal unit ( FIG. 1 , 2 , & 3 —Dryer 22 —Humidity Control Sensor 50 )=25.0% Set dehydrator cooling coil 30 for neutral effect T out (Temp Sensor DB 3 )=T in (Temp Sensor 52 ) In this case, the operator does not want to add heat into the enclosure from the dehydrator. Process is complete when the desired temperature (72° F.)has been reached and the desired % moisture loss (approximately 0.2%-approximately 2.0%) has been achieved.
EXAMPLE 2
[0114] Product start temperature=55° F.
[0115] Enclosure environmental conditions:
Temperature=60° F. Relative Humidity=70% Dew Point=55° F.
[0119] Production area environmental conditions:
Temperature=70° F. Relative Humidity=70% Dew Point=64° F.
[0123] Desired Results:
Product temperature above production area dew point of 64° F.; therefore, set target temperature at 70° F. (Range 5°-10° F.) Raise product temperature from 55° F. to 70° F. Optimal processing vapor pressure deficit for selected product=1.2 kpa (Range about 0.5 kpa to about 3.0 kpa)
[0129] Calculations (from FIG. 4 )
vp sat at 70° F. (from FIG. 4 ) is 2.5 kpa vp air =2.5−1.20=1.3 (target in enclosure) From FIG. 4 , 1.3=47% RH
[0133] Therefore, the operator would take the following actions:
Sensible heat removal is not required; the product is already too cool. Set point for removing sensible heat ( FIG. 1 , 2 & 3 —Coil 16 —Temp Sensor DB 1 )=off. Cut off temperature (FIG. 3 —Temp Sensor DB 2 )=off. (Coil is off, but fan does run.) Set point for moisture removal unit ( FIG. 1 , 2 , & 3 —Dryer 22 —Humidity Control Sensor 50 )=47% Dehydrator cooling coil 30 is not required; the fruit is already cool. Set for using Temp Sensor 52 =72° F. (as precaution or off). Allow waste heat from the dehydration process to raise the temperature. Set dehydrator heating coil (FIG. 3 —Heating coil 28 ) using Temp. Sensor DB 3 to (75°-80° F.) to gradually raise the temperature of the enclosures and the fruit. Process is complete when the desired temperature (70° F.) has been reached and the desired % moisture loss (approximately 0.2%-approximately 2.0%) has been achieved.
[0140] While the system and method of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the systems, methods, and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. More specifically, it will be apparent that certain materials that are both functionally and mechanically related might be substituted for the materials described herein while the same or similar results would be achieved. All such similar substitutes and modifications to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims.
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A method and apparatus for pretreating a fresh food product to relieve the internal (turgor) pressure and adjust the product temperature Invention has an enclosure with an internal space, an air inlet and an air outlet An exhaust fan is in fluid communication with the internal space Rows of product containers are disposed on either side of the exhaust fan to form an airflow aisle with an open end. A cover extends over the airflow aisle and the open end to form an air plenum tunnel. The exhaust fan is activated to lower the air pressure within the tunnel and pull enclosure air through openings in and between the product containers and over and around the food product. The exhaust fan further circulates exhaust air over cooling coils and returns exhaust air to the internal space of the enclosure. An air conditioning mechanism is attached to the enclosure outlet
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CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
This application is a National Stage Entry of International Application No. PCT/JP2013/074927, filed Sep. 13, 2013, which claims priority from Japanese Patent Application No. 2012-216890, filed Sep. 28, 2012. The entire contents of the above-referenced applications are expressly incorporated herein by reference.
TECHNICAL FIELD
The present invention relates to a defect analysis device, a defect analysis method, and a program.
BACKGROUND ART
With the progress of IT and network technology supported by digitalization, an amount of information processed by a person and an electronic device and stored is steadily increasing. Correct data on a phenomenon is acquired by a sensor that is an input device, correctly analyzed, assessed, processed, and recognized as useful information by a person. This is positioned as important activities for constructing a secure and safe society to a human society which becomes unconnected to a large amount of information.
In a modern life, facilities such as a water supply and sewerage network, a high-pressure chemical pipeline for gas, petroleum, or the like, a high-speed railway, a long span bridge, a tower building, a large commercial airplane, a car, and the like are created and used as the infrastructure of an affluent society. If these facilities are broken by natural disaster such as an unexpected earthquake or the like or aged deterioration and this results in a major accident, the accident has a lot of influence on the society and an economic loss is large. Deterioration due to corrosion, abrasion, backlash, or the like of a member used for the facility increases with the time. Lastly, malfunction such as breaking or the like occurs. In order to secure the safety and security of the facilities, many efforts are focused on the technical development beyond the academic areas of science, engineering, social science, and the like. A non-destructive testing technology in which a test can be performed at low cost and by a simple operation becomes important to prevent the major accident due to deterioration and breaking of the facilities.
By the way, as a liquid leakage test performed to detect liquid leakage due to deterioration or breaking of a pipe, a check by ear in which a person hears the sound generated by the leakage is usually used.
However, in many cases, the pipe is buried in the ground or installed on a high place of a building. Therefore, it is dangerous to perform the check by ear and requires a lot of labor. For this reason, the check cannot be performed with high accuracy and cannot be sufficiently performed. Further, a degree of proficiency of a checker has an influence on the accuracy of the result. Currently, because the degree of proficiency of the checker is low, it is difficult to prevent a leakage accident.
Further, when water leak is detected, it is required to specify the location of the leakage with a high degree of accuracy to reduce a repair cost. Today, a specialized checker specifies the location by the check by ear.
However, when an external noise such as a traffic noise generated by traffic or the like exists and a frequency component of the sound generated by the water leak is similar to that of the external noise, the check is disturbed by the external noise and it becomes difficult to determine whether the water leak occurs. For this reason, some countermeasures are taken, for example, the check is performed in a midnight time zone in which the external noise hardly occurs. However, the checker is greatly burdened by this.
In order to solve such problem, various leakage check methods using an instrument are proposed.
Patent Literature 1 (PTL1) discloses a leakage detection device composed of a vibration detection device having a pickup including a piezoelectric element, a detection device main body including a voltage amplifier which performs voltage amplification of an output signal and a plurality of kinds of noise elimination means which eliminate noise from the output signal, and a headphone.
Patent Literature 2 (PTL2) discloses a leak amount measuring device including a video observation device which observes a video of a leaking fluid, a sound measuring device which measures sound of the leaking fluid, a feature amount extraction device which extracts a feature amount of the leaking fluid from the outputs of the video observation device and the sound measuring device, and a leak amount retrieval device which calculates a leak amount by retrieving a database related to the leak amount that is created for each of pressure and temperature of the fluid, a phase state, and an area, a shape, or the like of a leak part.
Patent Literature 3 (PTL3) discloses a water leak detection method of which a water pipe and water in this water pipe are excited by a sound wave emitted by a sound wave source installed to a branch pipe laid on the ground that is connected to a water pipe buried in the ground, the sound wave is detected by a sound wave receiver on the surface of the ground, a signal processing of the detection signal of the sound wave is performed in synchronization with an excitation signal of the sound wave source, and water leak is detected based on a phenomenon in which the level of the detection signal changes according to the presence or absence of water leak.
CITATION LIST
Patent Literature
[PTL 1] Japanese Patent Application Laid-Open No. 2009-002873
[PTL 2] Japanese Patent Application Laid-Open No. 2000-310577
[PTL 3] Japanese Patent Application Laid-Open No. Sho 60-238734
SUMMARY OF THE INVENTION
Technical Problem
The inventors of this present application expects that when not only the presence or absence of a defect of a pipe and the location of a defect but also a degree of defect can be specified with a high degree of accuracy, urgency of repair work to repair each defect and the like can be appropriately grasped and whereby, a predetermined countermeasure can be implemented before the major accident occurs and the defect that causes the major accident can be reduced.
The technologies described in Patent Literature 1 (PTL1) and Patent Literature 3 (PTL3) are used for detecting the presence or absence of fluid leak and specifying the location of the defect. Therefore, the degree of defect cannot be specified by using these technologies.
In the technology described in Patent Literature 2 (PTL2), the sound and the video of the leaking fluid are measured and the leak amount is specified by using the feature amount. However, when this technology is used, the accuracy of the measured data of the sound and the like of the leaking fluid is low. Accordingly, the accuracy of the leak amount specified based on the data is also low. For example, when the external noise such as a traffic noise or the like exists and a frequency component of the sound generated by the water leak is similar to that of the external noise, it becomes difficult to determine the leak amount.
An object of the present invention is to provide a technology to specify the degree of defect of the pipe with a high degree of accuracy.
Solution to Problem
By the present invention, a defect analysis device including
vibration means which apply vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
first detection means which detect the vibration applied by the vibration means, and
signal processing means which extract a feature amount from a vibration waveform acquired by the first detection means and estimate a degree of defect formed in the pipe by using the extracted feature amount is provided.
Further, by the present invention,
a defect analysis method of which a computer executes
a vibration step of applying vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
a first detection step of detecting the vibration applied in the vibration step, and
a signal processing step of extracting a feature amount from a vibration waveform acquired in the first detection step and estimating a degree of defect formed in the pipe by using the extracted feature amount is provided.
By the present invention,
a program which causes a computer to function as
vibration means which apply vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
first detection means which detect the vibration applied by the vibration means, and
signal processing means which extract a feature amount from a vibration waveform acquired by the first detection means and estimate a degree of defect formed in the pipe by using the extracted feature amount is provided.
Advantageous Effects of Invention
By the present invention, a technology to specify the degree of defect in the pipe with a high degree of accuracy can be realized.
BRIEF DESCRIPTION OF DRAWINGS
The above-mentioned object, the other object, features, and advantages of the present invention will be apparent from the following description of the preferred exemplary embodiments and the following accompanying drawings thereof.
FIG. 1 is an example of a conceptual rendering of a defect analysis device according to an exemplary embodiment.
FIG. 2 is an example of a signal outputted from a vibration unit.
FIG. 3 is a flowchart showing an example of a process flow of a defect analysis method according to an exemplary embodiment.
FIG. 4 shows an example of frequency response data obtained by an exemplary embodiment.
FIG. 5 is a figure for explaining an effect on operation of an exemplary embodiment.
FIG. 6 is an example of a conceptual rendering of a defect analysis device according to an exemplary embodiment.
FIG. 7 is an example of a conceptual rendering of a defect analysis device according to an exemplary embodiment.
FIG. 8 is an example of a conceptual rendering of a defect analysis device according to an exemplary embodiment.
FIG. 9 is an example of a conceptual rendering of a defect analysis device according to an exemplary embodiment.
FIG. 10 is a figure for explaining a configuration of a defect analysis device of an example.
FIG. 11 is a figure for explaining a result of an example.
FIG. 12 shows an example of reference data of an exemplary embodiment.
FIG. 13 shows an example of reference data of an exemplary embodiment.
FIG. 14 shows an example of reference data of an exemplary embodiment.
DESCRIPTION OF EMBODIMENTS
An exemplary embodiment of the present invention will be described below with reference to a drawing.
Further, a device according to this exemplary embodiment is realized by an arbitrary combination of hardware which mainly includes a CPU in an arbitrary computer, a memory, a program loaded in the memory (including a program stored in the memory in advance before delivery of the device and a program downloaded from a storage medium such as a CD or the like or a server or the like on the Internet), a storage unit such as a hard disk or the like for storing the program, and an interface for network connection and software. It is understood by the person skilled in the art that a method for realizing the device and the device include various modifications.
In a functional block diagram used for explaining the exemplary embodiment, each block is a functional block and it does not represent a hardware unit. It is shown in these figures that each device is realized as one device. However, a method for realizing each device is not limited to this method. Namely, each device may be realized by two or more physically separated devices or two or more logically separated devices.
(First Exemplary Embodiment)
FIG. 1 shows an example of a conceptual rendering of a defect analysis device according to a first exemplary embodiment.
The defect analysis device includes a vibration unit 107 , a first detection unit 106 , a second detection unit 105 , and a processing device 100 . The processing device 100 includes a signal processing unit 101 , a transmission/reception unit 102 , a detection signal reception unit 103 , a reference data storage unit 104 , and a pipe information acquisition unit 115 . The processing device 100 is connected to the vibration unit 107 , the first detection unit 106 , and the second detection unit 105 so as to be communicable to each other through a wired or wireless connection and the processing device 100 can transmit/receive predetermined information to/from the vibration unit 107 , the first detection unit 106 , and the second detection unit 105 .
The vibration unit 107 and the second detection unit 105 are installed on an outer surface of a pipe 108 installed in the ground. The vibration unit 107 and the second detection unit 105 may be permanently installed on the outer surface of the pipe 108 . The first detection unit 106 is installed on the surface of the ground. An installation location of the processing device 100 is not limited in particular. For example, it is installed on the ground.
Here, a concept of the exemplary embodiment will be described briefly.
As shown in FIG. 1 , when the pipe 108 filled with fluid 110 has a defect (such as a hole or the like) through which the fluid leaks, a predetermined amount of fluid 110 is pushed out through the defect (such as the hole or the like) of the pipe 108 according to a pressure applied by a pump which sends the fluid 110 out and the shape, the size, or the like of the defect and whereby, a leak part 109 is generated. In this case, the pressure is applied to the fluid 110 and the pipe 108 by the flow of the fluid 110 and the vibration is excited. The generated vibration propagates along the pipe 108 and the fluid 110 for example, in the horizontal direction of FIG. 1 . In this exemplary embodiment, this vibration is detected by the second detection unit 105 and the detection signal is analyzed. Whereby, it is detected that the leak part 109 (defect) is formed in the pipe 108 .
Further, the vibration generated when the fluid 110 leaks from the leak part 109 is propagated to the outside of the pipe 108 by the fluid 110 leaking from the leak part 109 . In this exemplary embodiment, the vibration with a sufficiently large amplitude is applied to the pipe 108 by the vibration unit 107 . The vibration applied to the pipe 108 is also transmitted to the fluid 110 flowing in the pipe 108 . The vibration propagates through the pipe 108 and the fluid 110 in the pipe 108 . In this exemplary embodiment, the amplitude of the vibration is set so that when the vibration propagates to the outside of the pipe 108 through the leak part 109 and transmits through the ground, the vibration with a sufficiently large amplitude reaches the surface of the ground. In this exemplary embodiment, the vibration which reaches the surface of the ground is detected by the first detection unit 106 and the detection signal is analyzed. Whereby, the location of the leak part 109 (defect) is specified and a degree of defect is estimated.
Each unit will be described in detail below.
The second detection unit 105 detects at least one of the vibration propagating through the pipes 108 and the vibration propagating through the fluid 110 flowing in the pipes 108 . More specifically, the second detection unit 105 detects at least one of the vibration propagating through the pipes 108 and the vibration propagating through the fluid 110 flowing in the pipes 108 that are generated when the fluid leaks from the leak part 109 formed in the pipe 108 . In a case of an example shown in FIG. 1 , the second detection unit 105 is attached on the outer surface of the pipe 108 and detects the vibration propagating through the pipe 108 .
As the second detection unit 105 , for example, a sensor for measuring vibration of a solid can be used. A piezoelectric acceleration sensor, an electrodynamic acceleration sensor, a capacitance type acceleration sensor, an optical velocity sensor, a dynamic strain sensor, or the like can be used for the sensor for measuring vibration of a solid. For example, in a case in which the fluid 110 is water and the pipe 108 is a steel pipe, the vibration generated when water leaks has a frequency component of several 10 Hz to several kHz. The piezoelectric acceleration sensor is suitable for detection of such vibration. For attaching the second detection unit 105 on the surface of the pipe 108 , for example, a magnet, a dedicated jig, or an adhesive material can be used.
For example, the second detection unit 105 is permanently attached on the outer surface of the pipe 108 and measures the vibration propagating through the pipe 108 at all times or intermittently (for example, one time a day, one time an hour, ten times every three minutes, or the like). Data of measured vibration is transmitted to the transmission/reception unit 102 of the processing device 100 described later.
Further, although not shown in FIG. 1 , a plurality of second detection units 105 may be installed on the outer surface of the pipe 108 at a predetermined interval. In this case, the transmission/reception unit 102 acquires the data of vibration from each of a plurality of the second detection units 105 . Therefore, the transmission/reception unit 102 discriminates the second detection unit 105 transmitting the data of vibration and acquires the data. This operation can be realized by a conventional technology.
The vibration unit 107 applies the vibration (for example, a sound wave) with a plurality of frequency components to the pipe 108 . The vibration applied to the pipe 108 is also transmitted to the fluid 110 flowing in the pipe 108 . A piezoelectric vibration exciter, an electrodynamic vibration exciter, a mechanical vibration exciter, or the like can be used for the vibration unit 107 . For attaching the vibration unit 107 on the outer surface of the pipe 108 , for example, a magnet, a dedicated jig, or an adhesive material can be used.
The vibration applied by the vibration unit 107 propagates through the pipe 108 and the fluid 110 along a piping system. The vibration propagates in the horizontal direction of FIG. 1 . However, when the leak part 109 exists in the pipe 108 , a part of the vibration propagates to the outside of the pipe 108 through the leak part 109 . By adjusting the amplitude of the vibration applied by the vibration unit 107 , the vibration with a sufficiently large amplitude that propagates to the outside of the pipe 108 through the leak part 109 can reach the surface of the ground.
Further, the frequency of the vibration which easily propagates to the outside of the pipe 108 through the leak part 109 varies according to the size, the shape, or the like of the hole forming the leak part 109 . Namely, a state in which the vibration with a first frequency easily propagates to the outside of the pipe 108 through a first leak part 109 but the vibration with a second frequency does not easily propagate to the outside of the pipe 108 through a first leak part 109 occurs. In this exemplary embodiment, because the vibration unit 107 applies the vibration with a plurality of frequency components, the vibration can easily propagate to the outside of the pipe through the leak part 109 independently of the size, the shape, or the like of the hole forming the leak part 109 .
Further, means for applying the vibration with a plurality of frequency components is not limited in particular. The vibration with a plurality of frequency components may be applied or the vibration with one frequency component whose frequency can be changed may be applied while changing the frequency in turn. A signal having a wide frequency bandwidth is suitable for an inputted waveform. In FIG. 2 , a frequency sweep signal whose frequency varies with time is shown as an example. For example, white noise, a pulse signal, or the like can also be used as the input signal.
The vibration unit 107 applies the above-mentioned vibration to the fluid 110 flowing in the pipe 108 in which the leak part 109 is detected. Namely, it is not necessary for the vibration unit 107 to apply the vibration at all times. After it is detected that the leak part 109 exists in the pipe 108 , the vibration unit 107 can start to apply the vibration. For example, when a drive waveform is inputted from the processing device 100 described later, the vibration unit 107 can perform a process for applying the vibration according to the drive waveform.
The first detection unit 106 detects the vibration applied by the vibration unit 107 . Specifically, the first detection unit 106 detects the vibration radiated to the outside of the pipe 108 through the leak part 109 in the vibration applied by the vibration unit 107 . More specifically, the first detection unit 106 is installed on the surface of the ground and detects the vibration that is radiated to the outside of the pipe 108 and reaches the surface of the ground. Further, the first detection units 106 can be installed at a plurality of locations on the surface of the ground by changing the installation location and detect the vibration at each of a plurality of the installation locations.
As the first detection unit 106 , for example, a sensor for measuring vibration of a solid can be used. A piezoelectric acceleration sensor, an electrodynamic acceleration sensor, a capacitance type acceleration sensor, an optical velocity sensor, a dynamic strain sensor, or the like can be used as the sensor for measuring vibration of a solid. The piezoelectric acceleration sensor is suitable for this purpose.
The first detection unit 106 transmits the measured data of vibration to the detection signal reception unit 103 of the processing device 100 described below.
Next, each unit included in the processing device 100 will be described.
The transmission/reception unit 102 has a function to receive the data (analog signal) of vibration measured by the second detection unit 105 from the second detection unit 105 , a function to convert the received analog signal into a digital signal and transfer it to the signal processing unit 101 , and a function to output the drive waveform to the vibration unit 107 according to the signal transferred from the signal processing unit 101 . Specifically, the transmission/reception unit 102 has a signal amplification function, an analog-to-digital conversion function, and a digital-to-analog conversion function.
The detection signal reception unit 103 has a function to receive the data (analog signal) of vibration measured by the first detection unit 106 from the first detection unit 106 and a function to convert the received analog signal into the digital signal and transfer it to the signal processing unit 101 . Specifically, the detection signal reception unit 103 has a signal amplification function and an analog-to-digital conversion function.
The signal processing unit 101 treats the signal (the data of vibration) measured by the second detection unit 105 at all times or intermittently (for example, one time a day, one time an hour, ten times every three minutes, or the like) and monitors whether or not the leak part 109 is formed in the pipe 108 .
Further, the signal processing unit 101 treats the signal (the data of vibration) measured by each of a plurality of the second detection units 105 installed at a predetermined interval and specifies a coarse indication of the location of the leak part 109 formed in the pipe 108 .
Further, the signal processing unit 101 treats the signal (the data of vibration) measured at each of a plurality of installation locations by the first detection unit 106 and specifies the location of the leak part 109 formed in the pipe 108 .
Further, the signal processing unit 101 treats the signals (the data of vibration) measured by the first detection unit 106 and specifies the degree of the leak part 109 formed in the pipe 108 . Specifically, the signal processing unit 101 extracts a feature amount from the vibration waveform measured by the first detection unit 106 and estimates the degree of the leak part 109 formed in the pipe 108 by using the extracted feature amount.
The signal processing unit 101 treats the signal (the data of vibration) measured by the first detection unit 106 , extracts the amplitude as well as the frequency component of the vibration, and obtains frequency response data with at least one peak as shown in an example of FIG. 4 . The signal processing unit 101 extracts either a peak frequency or a sharpness of the peak, preferably both as the feature amount.
Further, the signal processing unit 101 estimates at least one of the size of the hole formed in the pipe 108 and an amount of the fluid 110 flowing to the outside of the pipe 108 through the hole formed in the pipe 108 as the degree of the leak part 109 (defect) formed in the pipe 108 .
Further, the signal processing unit 101 controls the signal (the drive waveform) inputted to the vibration unit 107 .
Such signal processing unit 101 has a frequency analysis function, a threshold value determination function, and a filter function.
The reference data storage unit 104 stores data required for determining whether or not the leak part 109 exists, for calculating the size of the hole of the leak part 109 , and for calculating a leakage amount. For example, data showing a feature of the vibration obtained when the water leak occurred in the past is stored.
For example, the reference data storage unit 104 may store reference data in which the feature amount extracted from the vibration waveform by the signal processing unit 101 is associated with the information (for example, the diameter of the hole) showing the degree of the leak part 109 formed in the pipe 108 . Further, a relationship between the feature amount and the degree of the leak part 109 changes according to a structure (a thickness, a material, or the like) of the pipe 108 in which the leak part 109 is formed, an embedding environment (the soil density or the like), or the like. For this reason, the reference data storage unit 104 may store the reference data in which the above-mentioned feature amount is associated with the relationship between the feature amount and the degree of the leak part 109 for each condition.
The pipe information acquisition unit 115 acquires information about the pipe 108 located in the location in which the leak part 109 exists. For example, the pipe information acquisition unit 115 acquires information showing the structure (the thickness, the material, or the like) of the pipe 108 located in the location in which the leak part 109 exists and the embedding environment (the soil density or the like). Means for acquiring such information by the pipe information acquisition unit 115 is not limited in particular. For example, when the location of the leak part 109 is specified, a worker retrieves a material and specifies the above-mentioned information about the pipe 108 buried in the location in detail. Next, the worker inputs the specified information about the pipe 108 to the processing device 100 . The pipe information acquisition unit 115 acquires the inputted information about the pipe 108 located in the location in which the leak part 109 exists.
These processes performed by the processing device 100 will be explained in detail below.
Next, an example of a process flow of a defect analysis method performed by the defect analysis device according to the exemplary embodiment will be explained. FIG. 3 shows a flowchart showing an example of the process flow of the defect analysis method. As shown in FIG. 3 , the defect analysis method according to the exemplary embodiment includes a defect presence-absence determination step S 10 , a defect location specifying step S 20 , and a defect degree estimation step S 30 .
In the defect presence-absence determination step S 10 , after the transmission/reception unit 102 receives the data of vibration measured by the second detection unit 105 and performs a predetermined process to the received data of vibration, the transmission/reception unit 102 transfers it to the signal processing unit 101 . The signal processing unit 101 analyses the transferred data and determines whether or not the defect is formed in the pipe 108 .
It is generally known that when the leak part 109 is formed in the pipe 108 , the amplitude of the frequency component of the vibration in a certain frequency range is larger than that in a normal state. Namely, when the leak part 109 is formed in the pipe 108 , a feature in which the amplitude of the frequency component of the vibration in a certain frequency range is larger than that in a normal state appears in the data of vibration measured by the second detection unit 105 .
The signal processing unit 101 analyzes the data of vibration measured by the second detection unit 105 and determines whether or not this feature appears. Specifically, the signal processing unit 101 determines whether or not the amplitude exceeds a threshold value of the amplitude in the normal state and determines whether or not the leak part 109 is formed in the pipe 108 .
Further, the above-mentioned threshold value varies according to the factors such as the material of the pipe 108 , the diameter of the pipe 108 , the buried environment, and the like. For this reason, the signal processing unit 101 holds the threshold value corresponding to each of these factors in advance. When the signal processing unit 101 receives the data of vibration from each of a plurality of the second detection units 105 , the signal processing unit 101 may determine whether or not the leak part 109 is formed by using the threshold value corresponding to the factor in the installation location in which each of the second detection units 105 is installed. For example, in a case in which a plurality of the second detection units 105 are permanently installed on the pipe 108 , the signal processing unit 101 may associate the above-mentioned threshold value with each of a plurality of the second detection units 105 and hold the threshold value in advance.
Alternatively, the signal processing unit 101 may calculate the above-mentioned threshold value for each of the second detection units 105 by using the data of vibration obtained in the normal state in the past that is acquired from each of a plurality of the second detection units 105 . For example, the signal processing unit 101 may specify an upper limit value of the data of vibration in the normal state for each of the second detection units 105 and calculate the above-mentioned threshold value by using the specified upper limit value. The signal processing unit 101 may associate each second detection unit 105 or the location in which each second detection unit 105 is installed with the threshold value and output a determination result (whether or not the leak part 109 is formed) to the worker.
By this step, it can be detected by the signal processing unit 101 that the leak part 109 is formed in the pipe 108 . Further, the signal processing unit 101 grasps the second detection unit 105 transmitting the data of vibration by which the leak part 109 is detected and whereby, the signal processing unit 101 can roughly specify the location (in the range in which the second detection unit 105 can detect the vibration) of the leak part 109 .
In the defect presence-absence determination step S 10 , when it is determined by the signal processing unit 101 that the leak part 109 is formed in the pipe 108 , the process advances to the defect location specifying step S 20 .
In the defect location specifying step S 20 , the location of the leak part 109 (defect) is specified. The step S 20 may be composed of a first step in which the location of the leak part 109 is roughly specified (as a coarse indication) and a second step in which the location of the leak part 109 is precisely specified. Further, the process of the first step is not performed and only the process of the second step may be performed.
In the first step, the signal processing unit 101 specifies a coarse indication of the location of the leak part 109 by using the data of vibration measured by each of a plurality of the second detection units 105 .
As mentioned above, a plurality of the second detection units 105 are installed at a predetermined interval. For this reason, the feature in which “the amplitude of the frequency component of the vibration in a certain frequency range is larger than that in a normal state” that appears when the leak part 109 is formed can be detected by a plurality of the second detection units 105 . For example, the signal processing unit 101 may synchronize the data of vibration measured by each of a plurality of the second detection units 105 , calculate a time difference between the times at which this feature is detected by a plurality of the second detection units 105 , and specify the coarse indication of the location of the leak part 109 by using the time difference (correlation method).
In the second step, the vibration unit 107 applies the vibration with a plurality of frequency components to at least one of the fluid 110 flowing in the pipe 108 and the pipe 108 . In a state in which the vibration is applied, the installation location of the first detection unit 106 on the surface of the ground is changed (the first detection unit 106 is moved) and the vibration is measured by the first detection unit 106 at each of a plurality of the installation locations. Further, because the coarse indication of the location of the leak part 109 is specified in the first step, the vibration can be measured in the location specified as the coarse indication while changing the installation location of the first detection unit 106 . The signal processing unit 101 treats the data of vibration measured at each of a plurality of the installation locations by the first detection unit 106 and specifies the location of the leak part 109 .
Thus, when it is detected by the signal processing unit 101 that the leak part 109 is formed in the pipe 108 , the vibration unit 107 can start to apply the vibration to at least one of the fluid 110 and the pipe 108 . The first detection unit 106 detects the vibration applied by the vibration unit 107 . For example, when it is detected by the signal processing unit 101 that the leak part 109 is formed in the pipe 108 , the vibration unit 107 may use it as a trigger and start to apply the vibration. Alternatively, when the worker acquires information indicating that the leak part 109 is formed, the worker inputs an instruction which causes the vibration unit 107 to start to apply the vibration and then, the vibration unit 107 may use it as the trigger and start to apply the vibration. When such configuration is used, the vibration is prevented from being unnecessarily applied by the vibration unit 107 and the detection process by the first detection unit 106 can be suppressed and whereby, the power consumed by these processes can be reduced.
When the vibration (refer to for example, FIG. 2 ) applied by the vibration unit 107 propagates through the pipe 108 and the fluid 110 , a part of the vibration is transmitted to the outside of the pipe 108 through the leak part 109 and reaches the surface of the ground. The vibration which reaches the surface of the ground is measured by the first detection unit 106 . After the measurement, in the signal processing unit 101 , the amplitude as well as the frequency component of the vibration are extracted and the frequency response data with at least one peak as shown in an example of FIG. 4 is obtained. The frequency of the peak and the sharpness of the peak mainly depend on the size of the hole of the leak part 109 and further depend on the structure (the thickness, the material, or the like) of the pipe 108 and the embedding environment (the soil density or the like).
The signal processing unit 101 performs a comparison process in which the comparison of the data of vibration that are measured at a plurality of the installation locations by the first detection unit 106 is performed, determines the location in which the output level of the peak is maximum, and regards this location as the location just above the leak part 109 .
Further, in the second step, without using the signal processing unit 101 to specify the location of the leak part 109 , the worker can specify the location of the leak part 109 based on the frequency response data shown in FIG. 4 . For example, a method of which the first detection unit 106 is moved (automatically moved or manually moved by the worker) on the surface of the ground, the vibration is measured in each location by the first detection unit 106 , and the frequency response data (refer to FIG. 4 ) obtained by processing the measured data of vibration is displayed on a display in real time can be used. The worker may move the first detection unit 106 on the surface of the ground, confirm the frequency response data displayed on the display, and specify the installation location of the first detection unit 106 at which the output level of the peak is maximum.
Alternatively, without moving the first detection unit 106 on the surface of the ground, a method of which a plurality of the first detection units 106 are installed at a predetermined interval on the surface of the ground, the vibration is measured by each of a plurality of the first detection units 106 , and it is determined that the installation location of the first detection unit 106 at which the output level of the signal is maximum is just above the leak part 109 may be used.
Returning to FIG. 3 , in the defect degree estimation step S 30 , the vibration unit 107 applies the vibration with a plurality of frequency components to the pipe 108 . The vibration applied to the pipe 108 is also transmitted to the fluid 110 flowing in the pipe 108 . The vibration propagates through the pipe 108 and the fluid 110 in the pipe 108 . The first detection unit 106 measures the vibration in a state in which the vibration is applied. Namely, the first detection unit 106 measures the vibration applied by the vibration unit 107 . For example, the first detection unit 106 is installed in the location on the surface of the ground that is just above the leak part 109 specified in the defect location specifying step S 20 . The signal processing unit 101 treats the data of vibration measured by the first detection unit 106 and estimates the degree of the leak part 109 .
As explained by using FIG. 4 , the frequency and the shape of the peak in the above-mentioned frequency response data mainly depend on the size of the hole of the leak part 109 and also may depend on the structure (the thickness, the material, or the like) of the pipe 108 and the embedding environment (the soil density or the like). Namely, this means that this frequency response data can be used as an index indicating the size of the hole of the leak part 109 and the leakage amount.
FIG. 5 is an outline drawing showing a principle. As shown in FIG. 5 , when there are two leak parts 109 of which the sizes of the leak parts 109 are different from each other, the frequency response data including two peaks whose frequencies and sharpness Q are different from each other is obtained from the measurement. The feature amount and the size (the leak amount) of the hole of the leak part 109 have a predetermined relation to each other. Specifically, as shown in FIG. 5 , when the value of the peak frequency becomes small, the size of the hole of the leak part 109 becomes large. Further, when the value of the sharpness Q of the peak becomes large, the size of the hole of the leak part 109 becomes large. For this reason, when the reference data in which the size of the hole of the leak part 109 is associated with the feature amount (either the peak frequency or the sharpness or preferably both) extracted from the frequency response data is stored in the reference data storage unit 104 , the size of the hole of the leak part 109 can be specified by using the data of vibration measured by the first detection unit 106 .
Further, the relation between the size of the hole of the leak part 109 and the feature amount (either the peak frequency or the sharpness or preferably both) extracted from the frequency response data may depend on the structure (the thickness, the material, or the like) of the pipe 108 in which the leak part 109 exists and the embedding environment (the soil density or the like). For this reason, it is desirable to store the reference data in which the size of the hole of the leak part 109 is associated with the feature amount (either the peak frequency or the sharpness or preferably both) extracted from the frequency response data for each structure (the thickness, the material, or the like) of the pipe 108 or each embedding environment (the soil density or the like) in the reference data storage unit 104 .
Here, an example of the reference data is shown in FIGS. 12 to 14 . In an example shown in FIG. 12 , the size of the hole of the leak part 109 is associated with the peak frequency that is the feature amount extracted from the frequency response data for each thickness of the pipe 108 . In an example shown in FIG. 13 , the size of the hole of the leak part 109 is associated with the sharpness of the peak that is the feature amount extracted from the frequency response data for each thickness of the pipe 108 . In an example shown in FIG. 14 , the size of the hole of the leak part 109 is associated with the peak frequency that is the feature amount extracted from the frequency response data for each of the combinations of a plurality of information about the thickness, the material, and the like of the pipe 108 .
In this step, the signal processing unit 101 treats the data of vibration measured by the first detection unit 106 , obtains the frequency response data as shown in an example of FIG. 4 , and calculates either the peak frequency or the sharpness of the peak, or preferably both.
In this step, the pipe information acquisition unit 115 receives the information (the structure (the thickness, the material, or the like) of the pipe 108 , the embedding environment (the soil density or the like) around the location in which the leak part 109 of the pipe 108 exists, or the like) inputted by the worker. For example, when the location of the leak part 109 is specified in the defect location specifying step S 20 , the worker retrieves the predetermined material and specifies the information (the structure (the thickness, the material, or the like) of the pipe 108 , the embedding environment (the soil density or the like) around the location in which the leak part 109 of the pipe 108 exists or the like). After this process, the worker inputs the specified information about the pipe 108 to the processing device 100 . The pipe information acquisition unit 115 acquires the information about the pipe 108 (the structure (the thickness, the material, or the like) of the pipe 108 , the embedding environment (the soil density or the like), or the like) inputted in such a manner.
The signal processing unit 101 retrieves the reference data (refer to FIGS. 12 to 14 ) by using the information about the pipe 108 (the structure (the thickness, the material, or the like) of the pipe 108 , the embedding environment (the soil density or the like), or the like) acquired by the pipe information acquisition unit 115 as a key and specifies the reference data corresponding to the information about the pipe 108 . After this process, the signal processing unit 101 retrieves the specified reference data by using either the calculated peak frequency or the calculated sharpness or preferably both as the key and specifies the size of the hole. When the calculated peak frequency and the calculated sharpness are used as the key, the signal processing unit 101 retrieves the reference data by using the calculated peak frequency and the calculated sharpness as the key in turn and specifies the size of the hole. For example, when the size of the hole which is specified by using the peak frequency as the key is not equal to the size of the hole which is specified by using the sharpness as the key, the signal processing unit 101 may output the size of the hole that is larger than the other as a result.
Further, when the size of the hole can be specified, the leak amount of the fluid 110 can be calculated by using the size of the hole and the pressure applied by a pump so that the fluid 110 flows in the pipe 108 .
In the exemplary embodiment, the vibration is intentionally applied by the vibration unit 107 . Therefore, the timing of pressure application and the frequency component can be grasped. Namely, the vibration can be easily distinguished from a disturbance component.
By using the exemplary embodiment mentioned above, determination of whether the leak part 109 (defect) is formed, determination of the location of the leak part 109 (defect), and estimation of the degree of the leak part 109 (defect) can be performed without using the check by ear of the skilled checker.
Further, as described above, in the exemplary embodiment, the vibration applied by the vibration unit 107 is detected by the first detection unit 106 . The signal processing unit 101 extracts the feature amount from the vibration waveform acquired by the first detection unit 106 and estimates the degree of the leak part 109 (defect) formed in the pipe 108 by using the extracted feature amount.
Namely, in the exemplary embodiment, the vibration is applied to the fluid 110 and the pipe 108 , the vibration propagates through the fluid 110 and the pipe 108 , this vibration is detected and analyzed, and whereby, the degree of the leak part 109 (defect) is estimated. Therefore, the vibration with a sufficiently large amplitude can be detected and based on this detection result, the degree of the leak part 109 (defect) can be estimated with a high degree of accuracy.
Further, in the exemplary embodiment, the vibration unit 107 applies the vibration with a plurality of frequency components. As mentioned above, the easiness of transmission of the vibration to the outside of the pipe 108 through the leak part 109 (defect) depends on the frequency of the vibration. When this exemplary embodiment is used, because the vibration with a plurality of frequency components is applied, the vibration can easily propagate to the outside of the pipe 108 through the leak part 109 (defect). Therefore, the first detection unit 106 can detect the vibration with a sufficiently large amplitude that is transmitted to the outside of the pipe 108 through the leak part 109 (defect). As a result, the degree of the leak part 109 (defect) can be estimated with a high degree of accuracy.
(Second Exemplary Embodiment)
FIG. 6 shows an example of a conceptual rendering of a defect analysis device according to a second exemplary embodiment.
The present exemplary embodiment is different from the first exemplary embodiment in view of a point such that a processing device 100 , explained in first the exemplary embodiment, is composed of a first processing device 100 A and a second processing device 100 B physically separated each other. The configuration of the second exemplary embodiment other than this difference can be made the same as the configuration of the first exemplary embodiment. Therefore, the description will be omitted.
The first processing device 100 A includes a signal processing unit 101 and a transmission/reception unit 102 . The second processing device 100 B includes a signal processing unit 101 , a detection signal reception unit 103 , a reference data storage unit 104 , and a pipe information acquisition unit 115 . The first processing device 100 A and the second processing device 100 B are configured so as to be communicable to each other through a wireless connection. Further, the first processing device 100 A and the second processing device 100 B may be configured so as to be communicable to each other through a wired connection.
By using this exemplary embodiment, even when the vibration unit 107 is located far from the first detection unit 106 , the location of the leak part 109 can be specified and the degree of the leak part 109 can be estimated without difficulty.
(Third Exemplary Embodiment)
FIG. 7 shows an example of a conceptual rendering of a defect analysis device according to a third exemplary embodiment.
This exemplary embodiment is configured on the basis of the configuration of the second exemplary embodiment, and is different from that in view of point such that the reference data storage unit 104 is separately provided from the second processing device 100 B. The configuration of the third exemplary embodiment other than this difference can be made the same as the configuration of the second exemplary embodiment. Therefore, the description will be omitted.
The reference data storage unit 104 and the second processing device 100 B are configured so as to be communicable to each other through a wireless connection. Further, the reference data storage unit 104 and the second processing device 100 B may be configured so as to be communicable to each other through a wired connection. For example, the reference data storage unit 104 is included in a server or the like on a network and the second processing device 100 B accesses such reference data storage unit 104 and refers to the predetermined data.
This exemplary embodiment has an advantageous effect in which data can be integrally managed and an analysis that needs a lot of reference data which cannot be stored in the device can be performed.
(Fourth Exemplary Embodiment)
FIG. 8 shows an example of a conceptual rendering of a defect analysis device according to a fourth exemplary embodiment.
The present exemplary embodiment is different from the first to third exemplary embodiments in view of point such that the second detection unit 105 and the vibration unit 107 are installed inside the pipe 108 . The configuration of the fourth exemplary embodiment other than this difference can be made the same as the configuration of the first to third exemplary embodiments. Therefore, the description will be omitted.
By using this exemplary embodiment, it is possible to directly apply the vibration to the fluid 110 and directly detect the vibration propagating through the fluid 110 . In the fourth exemplary embodiment, it is necessary to insert the structural objects (the second detection unit 105 and the vibration unit 107 ) inside the pipe 108 unlike the first to third exemplary embodiments. Therefore, the second detection unit 105 and the vibration unit 107 cannot be easily installed. However, because the vibration in the fluid 110 that is less attenuated with distance can be directly treated, the fourth exemplary embodiment is useful when the leak part 109 is located far from the second detection unit 105 .
(Fifth Exemplary Embodiment)
FIG. 9 shows an example of a conceptual rendering of a defect analysis device according to a second exemplary embodiment.
The present exemplary embodiment is different from the first to fourth exemplary embodiments in view of point such that the second detection unit 105 and the vibration unit 107 are installed on the outer surface of a branch pipe 111 connected to the pipe 108 . The branch pipe 111 is a pipe connected to the pipe 108 that is an object of defect detection. For example, the exemplary embodiment may be applied to a case shown in FIG. 9 in which asphalt exists on the surface of the ground and the branch pipe 111 is a manhole. In this case, the second detection unit 105 and the vibration unit 107 may be installed on the inner surface of the manhole that is the branch pipe 111 . The configuration of the fifth exemplary embodiment other than this difference can be made the same as the configuration of the first to fourth exemplary embodiments. Therefore, the description will be omitted.
When this exemplary embodiment is used, the vibration unit 107 and the second detection unit 105 can be very easily installed. Therefore, this exemplary embodiment has an advantageous effect in which the labor and time required for the check work can be reduced.
In the exemplary embodiment described above, a case in which the fluid flowing in the pipe 108 is liquid has been explained as an example. However, the fluid may be gas. In the exemplary embodiments described above, a case in which the pipe 108 is installed under the ground has been explained as an example. However, the pipe 108 may be installed in an attic or a basement of a building or may be buried in a wall or a pillar. In this case, the first detection unit 106 can be installed on a ceiling surface, a wall surface, a side surface of the pillar, a floor surface, or the like.
EXAMPLE
A result of verification performed to verify availability of the above-mentioned exemplary embodiment will be described below.
FIG. 10 is a figure schematically showing a configuration of this example. In order to simulate water leak from a water pipe, a metal pipe 108 filled with water is prepared and buried under the ground. The branch pipe is connected to the pipe 108 . A second detection unit 105 and a vibration unit 107 are installed on the outer surface of this branch pipe. A pump for sending water is connected to the left end of the pipe 108 and operated. The hole for simulating a leak part 109 is provided on the way of the pipe 108 . Water leaks to the outside of the pipe 108 through this hole.
In this state, the data of vibration is measured by the second detection unit 105 . The feature in which the amplitude of the vibration with the frequency component in a certain range is larger than that in a normal state is observed. This phenomenon is caused by existence of the leak part 109 . Further, the measurement is repeated under different conditions under which the pipe wall thickness and the size of the hole of the leak part 109 are changed and the above-mentioned feature is observed in all the conditions. Namely, by using this exemplary embodiment, the leak part 109 of the pipe 108 can be detected. This is confirmed by the measurement result.
Next, the vibration with a sweep frequency is applied to the branch pipe by the vibration unit 107 and in this state, the vibration radiated to the outside of the pipe 108 through the leak part 109 is measured by the first detection unit 106 installed on the surface of the ground.
When the first detection unit 106 installed on the surface of the ground is moved by hand, the measured amplitude of the vibration varies according to the location of the first detection unit 106 . The measurement result shows that the location in which the measured amplitude of the vibration is maximum is a location just above the leak part 109 . Namely, by using this exemplary embodiment, the location of the leak part 109 of the pipe 108 can be specified. This is confirmed by the measurement result.
Next, a frequency analysis of the data of vibration acquired by the first detection unit 106 is performed by the signal processing unit 101 provided in the second processing device 100 B and then, the peak frequency and the value of the sharpness Q are extracted.
Similarly, the measurement is repeated under different conditions under which the pipe wall thickness of the pipe 108 and the size of the hole of the leak part 109 are changed. After the measurement, a plurality of measurement data are normalized so that the peak frequency, the sharpness Q, the pipe wall thickness, the diameter of the leak part, and the leakage amount in a condition in which the thickness of the pipe 108 is 5 mm and the diameter of the leak part 109 (the hole) is 5 mm are unity. The normalized value is shown in table 1 and FIG. 11 .
From this result, it is clear that the peak frequency and the sharpness systematically vary according to the change in the pipe wall thickness of the pipe 108 and the change in the diameter of the leak part 109 .
Here, it is verified whether the peak frequency and the sharpness can be used as the index of water leak or not. As an example, we focus on two points (No. 1 - 7 and No. 1 - 10 ) indicated by the arrows in FIG. 11 : one is a point (No. 1 - 10 ) at which the normalized pipe wall thickness is 4 and the normalized diameter of the leak part is 2 and the other is a point (No. 1 - 7 ) at which the normalized pipe wall thickness is 2 and the normalized diameter of the leak part is 6 are examined.
Two of the normalized leakage amounts at these two points are compared with each other. The normalized leakage amount at the point (No. 1 - 10 ) is 4 and the normalized leakage amount at the point (No. 1 - 7 ) is 36. When only the peak frequency is used as the index, the values of the peak frequencies at two points are very close to each other and it is difficult to distinguish them from each other. Namely, it shows that when the water leak occurs, there is a possibility that an erroneous determination is made for urgency. On the other hand, when the peak frequency and the sharpness Q of the peak are used as the index, it is easy to distinguish two states as clearly shown in FIG. 11 and table 1.
TABLE 1
NORMALIZED
NORMALIZED
NORMALIZED
NORMALIZED
NORMALIZED
LEAKAGE
NO.
FREQUENCY
SHARPNESS
DIAMETER
THICKNESS
AMOUNT
1-1
1.00
1.00
1
1
1
1-2
0.76
0.49
2
1
4
1-3
0.41
0.26
6
1
36
1-4
0.28
0.21
10
1
100
1-5
0.62
1.63
1
2
1
1-6
0.50
1.00
2
2
4
1-7
0.31
0.37
6
2
36
1-8
0.22
0.28
10
2
100
1-9
0.35
2.42
1
4
1
1-10
0.31
1.63
2
4
4
1-11
0.21
0.65
6
4
36
1-12
0.17
0.39
10
4
100
The reference data related to the structure (the thickness, the material, or the like) of the pipe 108 , the embedding environment (the soil density or the like), or the like is stored in the reference data storage unit 104 and the measurement result is compared with the reference data. Whereby, the size of the hole of the leak part 109 and the leakage amount can be easily calculated. In a series of measurements, the measurement has been performed without being affected by a car noise and a disturbance.
It has been shown above that determination of whether the leak part 109 (defect) is formed, determination of the location of the leak part 109 (defect), and estimation of the degree of the leak part 109 (defect) can be performed without using the check by ear of the skilled checker.
<<Supplementary Note>>
By the above-mentioned description, the following invention has been explained.
<Invention 1>
A defect analysis device including:
vibration means for applying vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
first detection means for detecting the vibration applied by the vibration means, and
signal processing means for extracting a feature amount from a vibration waveform acquired by the first detection means and estimate a degree of defect formed in the pipe by using the extracted feature amount.
<Invention 2>
The defect analysis device described in invention 1, wherein
the signal processing means extract at least one of a peak frequency and a sharpness of a peak as the feature amount.
<Invention 3>
The defect analysis device described in invention 1 or invention 2, wherein
the signal processing means estimate at least one of a size of a hole formed in the pipe and an amount of fluid which leaks to the outside of the pipe through the hole formed in the pipe as the degree of defect formed in the pipe.
<Invention 4>
The defect analysis device described in any one of inventions 1 to 3, wherein
the defect analysis device further includes reference data storage means for storing reference data in which the feature amount is associated with information indicating the degree of defect formed in the pipe and
the signal processing means retrieve the reference data by using the feature amount as a key and estimate the degree of defect formed in the pipe.
<Invention 5>
The defect analysis device described in invention 4, wherein
the defect analysis device further includes pipe information acquisition means for acquiring information about the pipe in which defect exists,
the reference data storage mean store the reference data for each of the information about the pipe, and
the signal processing means specify the reference data to be retrieved by using the information about the pipe acquired by the pipe information acquisition means and retrieve the specified reference data by using the feature amount as the key.
<Invention 6>
The defect analysis device described in any one of inventions 1 to 5, wherein
the vibration means apply vibration to at least one of the fluid flowing in the pipe in which defect is detected and the pipe and
the first detection means detect the vibration radiated to the outside of the pipe through the defect.
<Invention 7>
The defect analysis device described in any one of inventions 1 to 6, wherein
the vibration means are installed on the outer surface of the pipe or the outer surface of a branch pipe connected to the pipe.
<Invention 8>
The defect analysis device described in any one of inventions 1 to 7, wherein
the pipe is installed under the ground and
the first detection means are installed on the surface of the ground and detect the vibration that is radiated to the outside of the pipe and reaches the surface of the ground.
<Invention 9>
The defect analysis device described in invention 8, wherein
the first detection means can be moved to a plurality of different locations on the surface of the ground and detect the vibration at each of a plurality of the installation locations and
the signal processing means use a plurality of vibration waveforms acquired at each of a plurality of the installation locations by the first detection means and specify the location of the defect formed in the pipe.
<Invention 10>
The defect analysis device described in any one of inventions 1 to 9, wherein
the defect analysis device further includes second detection means for detecting at least one of the vibration propagating through the pipe and the vibration propagating through the fluid flowing in the pipe and
the signal processing means detect the formation of defect in the pipe by using the vibration detected by the second detection means.
<Invention 11>
The defect analysis device described in invention 10, wherein
the second detection means are installed on the outer surface of the pipe or the outer surface of the branch pipe connected to the pipe.
<Invention 12>
The defect analysis device described in invention 10 or invention 11, wherein
the defect analysis device includes a plurality of the second detection means and a plurality of the second detection means are installed at a predetermined interval and
the signal processing means specify a coarse indication of the location of the defect formed in the pipe by using the vibration detected by each of a plurality of the second detection means.
<Invention 13>
The defect analysis device described in any one of inventions 10 to 12, wherein
when the signal processing means detect the formation of defect in the pipe, the vibration means start to apply the vibration and the first detection means detect the vibration applied by the vibration means.
<Invention 14>
A defect analysis method of which a computer executes:
a vibration step of applying vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
a first detection step of detecting the vibration applied in the vibration step, and
a signal processing step of extracting a feature amount from a vibration waveform acquired in the first detection step and estimating a degree of defect formed in the pipe by using the extracted feature amount.
<Invention 14-2>
The defect analysis method described in invention 14, wherein
in the signal processing step, at least one of a peak frequency and a sharpness of a peak is extracted as the feature amount.
<Invention 14-3>
The defect analysis method described in invention 14 or invention 14-2, wherein
in the signal processing step, at least one of a size of a hole formed in the pipe and an amount of fluid which leaks to the outside of the pipe through the hole formed in the pipe is estimated as the degree of the defect formed in the pipe.
<Invention 14-4>
The defect analysis method described in any one of inventions 14 to 14-3, wherein
the computer
stores reference data in which the feature amount is associated with information indicating the degree of defect formed in the pipe and
retrieves the reference data by using the feature amount as a key and estimates the degree of defect formed in the pipe in the signal processing step.
<Invention 14-5>
The defect analysis method described in invention 14-4, wherein
the computer
further executes a pipe information acquisition step of acquiring information about the pipe in which the defect exists,
stores the reference data for each of the information about the pipe, and
specifies the reference data to be retrieved by using the information about the pipe acquired in the pipe information acquisition step and retrieves the specified reference data by using the feature amount as the key in the signal processing step.
<Invention 14-6>
The defect analysis method described in any one of inventions 14 to 14-5, wherein
in the vibration step, the vibration is applied to at least one of the fluid flowing in the pipe in which the defect is detected and the pipe and
in the first detection step, the vibration radiated to the outside of the pipe through the defect is detected.
<Invention 14-7>
The defect analysis method described in any one of inventions 14 to 14-6, wherein
a vibration unit which applies the vibration in the vibration step is installed on the outer surface of the pipe or the outer surface of a branch pipe connected to the pipe.
<Invention 14-8>
The defect analysis method described in any one of inventions 14 to 14-7, wherein
the pipe is installed under the ground and
a first detection unit which detects the vibration in the first detection step is installed on the surface of the ground and detects the vibration that is radiated to the outside of the pipe and reaches the surface of the ground.
<Invention 14-9>
The defect analysis method described in invention 14-8, wherein
in the first detection step, the first detection unit can be moved to a plurality of different locations on the surface of the ground and detect the vibration at each of a plurality of the installation locations and
in the signal processing step, the location of the defect formed in the pipe is specified by using a plurality of vibration waveforms acquired at each of a plurality of the installation locations by the first detection unit.
<Invention 14-10>
The defect analysis method described in any one of inventions 14 to 14-9, wherein
the computer
further executes a second detection step of detecting at least one of the vibration propagating through the pipe and the vibration propagating through the fluid flowing in the pipe and
detects the formation of defect in the pipe by using the vibration detected in the second detection step in the signal processing step.
<Invention 14-11>
The defect analysis method described in invention 14-10, wherein
a second detection unit which detects the vibration in the second detection step is installed on the outer surface of the pipe or the outer surface of the branch pipe connected to the pipe.
<Invention 14-12>
The defect analysis method described in invention 14-11, wherein
a plurality of the second detection units are used and installed at a predetermined interval and
in the signal processing step, a coarse indication of the location of the defect formed in the pipe is specified by using the vibration detected by each of a plurality of the second detection units.
<Invention 14-13>
The defect analysis method described in any one of inventions 14-10 to 14-12, wherein
when the formation of defect in the pipe is detected in the signal processing step, application of vibration is started in the vibration step and the vibration is detected in the first detection step.
<Invention 15>
A program which causes a computer to function as:
vibration means for applying vibration with a plurality of frequency components to at least one of fluid flowing in a pipe and the pipe,
first detection means for detecting the vibration applied by the vibration means, and
signal processing means for extracting a feature amount from a vibration waveform acquired by the first detection means and estimate a degree of defect formed in the pipe by using the extracted feature amount.
<Invention 15-2>
The program described in invention 15, which causes the signal processing means to extract at least one of a peak frequency and a sharpness of a peak as the feature amount.
<Invention 15-3>
The program described in invention 15 or invention 15-2, which causes the signal processing means to estimate at least one of a size of a hole formed in the pipe and an amount of fluid which leaks to the outside of the pipe through the hole formed in the pipe as a degree of defect formed in the pipe.
<Invention 15-4>
The program described in any one of inventions 15 to 15-3, which causes the computer to
further function as reference data storage means for storing reference data in which the feature amount is associated with information indicating the degree of defect formed in the pipe and
make the signal processing means retrieve the reference data by using the feature amount as a key and estimate the degree of defect formed in the pipe.
<Invention 15-5>
The program described in invention 15-4, which causes the computer to
further function as
pipe information acquisition means for acquiring information about the pipe in which defect exists,
make the reference data storage means store the reference data for each of the information about the pipe, and
make the signal processing means specify the reference data to be retrieved by using the information about the pipe acquired by the pipe information acquisition means and retrieve the specified reference data by using the feature amount as the key.
<Invention 15-6>
The program described in any one of inventions 15 to 15-5, which causes
the vibration means to apply the vibration to at least one of the fluid flowing in the pipe in which the defect is detected and the pipe and
the first detection means to detect the vibration radiated to the outside of the pipe through the defect.
<Invention 15-7>
The program described in any one of inventions 15 to 15-6, which causes
the vibration means to make a vibration unit installed on the outer surface of the pipe or the outer surface of the branch pipe connected to the pipe apply the vibration.
<Invention 15-8>
The program described in any one of inventions 15 to 15-7, wherein
the pipe is installed under the ground and
the program is a program which causes
the first detection means to detect the vibration that is radiated to the outside of the pipe and reaches the surface of the ground.
<Invention 15-9>
The program described in invention 15-8, which causes
the first detection means to detect the vibration at each of a plurality of installation locations when the first detection means are moved to a plurality of different locations on the surface of the ground and
the signal processing means to specify the location of defect formed in the pipe by using a plurality of vibration waveforms acquired at each of a plurality of the installation locations by the first detection means.
<Invention 15-10>
The program described in any one of inventions 15 to 15-9, which causes the computer to
further function as second detection means for detecting at least one of the vibration propagating through the pipe and the vibration propagating through the fluid flowing in the pipe and
make the signal processing means detect the formation of defect in the pipe by using the vibration detected by the second detection means.
<Invention 15-11>
The program described in invention 15-10, which causes the second detection means to make a sensor installed on the outer surface of the pipe or the outer surface of the branch pipe connected to the pipe detect the vibration.
<Invention 15-12>
The program described in invention 15-11, wherein
a plurality of the sensors are used when the second detection means detect the vibration and a plurality of the sensors are installed at a predetermined interval and
the program is a program which causes the signal processing means to specify a coarse indication of the location of the defect formed in the pipe by using the vibration detected by each of a plurality of the sensors.
<Invention 15-13>
The program described in any one of inventions 15-10 to 15-12, which causes the vibration means to start to apply the vibration and the first detection means to detect the vibration applied by the vibration means after the signal processing means detect the formation of defect in the pipe.
This application is based upon and claims the benefit of priority from Japanese patent application No. 2012-216890, filed on Sep. 28, 2012, the disclosure of which is incorporated herein in its entirety by reference.
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The present invention provides a defect analysis device including: an excitation unit ( 107 ) that imparts vibrations of a plurality of frequencies to a fluid ( 110 ) flowing through a pipe ( 108 ); a first detector ( 106 ) that, when the excitation part ( 107 ) is imparting vibrations, detects vibrations emanating from the pipe ( 108 ); and a signal processing unit ( 101 ) that extracts a feature quantity from a vibration waveform acquired by the first detector ( 106 ), and uses the extracted feature quantity to estimate the extent of a defect formed in the pipe ( 108 ).
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FIELD OF THE INVENTION
[0001] The present invention relates to a process for selectively decolorizing mercerized and dyed threads, yarns and fabrics and improving their hand. More particularly, there is provided a process for removing or decolorizing dye which is plated or surface dyed on the threads, yarns or fabrics utilizing mercerizing with ozone.
BACKGROUND OF THE INVENTION
[0002] Mercerization is widely used, and in the mercerization of different kinds of cellulose products, including blended products. Post-dyeing mercerization is rarely used since there is a significant difference in the quality of the finished product such as luster, depth and shade as well as the shape. However, pre-dyeing mercerization with a base results in the formation of an alkali cellulose outer shell on the fibers. Dyeing of mercerized fabrics can result in dye being plated on the outside of the fibers which results in irregular fabric finishing. Moreover, the inner pants of the fibers have the natural cellulose still existing so that the fibers still do not have the softness achieved with the initial mercerization.
[0003] Processes for stripping dyes from or decolorizing various materials are known in the art. For example, U.S. Pat. No. 4,227,881 discloses a process for stripping dyes from textile fabric which includes heating an aqueous solution of an ammonium salt, a sulfite salt and an organic sulfonate to at least 140 degree F. (60 degree C.) and adding the dyed fabric to the heated solution while maintaining the temperature of the solution. In addition to the costly heating and temperature maintenance step, this process has the drawback of producing fabric which after processing exhibits a remaining color depth. U.S. Pat. No. 4,783,193 discloses a process for stripping color from synthetic polymer products by contacting the colored polymer with a chemical system. The described process uses unstable dispersions of alkyl halides and aqueous solutions of bleaching/oxidizing agents to which specified quantities of acids and surfactant/wetting agents are added. Among the drawbacks are the uses of potentially hazardous halogens and the special provisions required to prevent escape of vapors which could cause environmental harm. Further, the use of the chemical system may restrict or eliminate the polymeric material's recycleability. In general, processes which utilize harsh stripping agents destroy the usefulness of the colorant, thus generating a chemical waste stream that must be treated or disposed of in an environmentally conscious manner. These methods can also generate unremovable colorant fragments which limit the downstream recycleability and utility of the color-stripped material. The methods are not suitable for selectively removing dye from the surfaces only of the textile material.
[0004] It is known to decolorize and desize dyed cellulosic fabric utilizing ozone, for example U.S. Pat. No. 5,366,510 to Wasinger. Dyes for cellulosic fibers have five major color application categories designated specifically for this chemical fiber type. Direct, vat, sulfur and reactive, along with azoic combinations. This is in sharp contract to dyeing man-made fibers which include acetate, acrylic, modacrylic, nylon, polyester and polyurethane fibers which are chemically diverse, mostly hydrophobic and are colored by disperse dye application. The most important fibers, polyester, nylon and cellulose acetate are generally disperse dyed. Acrylic and modacrylic can be dyed with both basic and disperse dyes. On acrylic fibers disperse dyes do not build well.
[0005] In batch dyeing the dye particles become associated with the surface of the synthetic fibers and then penetrate directly into the synthetic fiber. However, some dyes have the tendency to plate the surface of the fibers such as polyester before the dye has an opportunity to penetrate the fiber. Problems occur when there is an excess of soluble dye or disperse dye in the dye bath due to the concentration of the dye present exceeding the Saturation solubility of the dye at the particular dye temperature so that the dye does not transfer into the fiber but plates on the surface. It would be desirable to dissolve the plated dye which leads to specks.
[0006] Some of the problem found is when there is a mixture of fibers and the rate of dyeing and the temperatures of dyeing differ for each fiber so that the dye does not dissolve or penetrate into the fiber but plates the surface.
[0007] The problems in the industry are found when utilizing vat dyeing or mainstream equipment such as jets, wenches, beams or package dyeing.
[0008] Because disperse dyes have no or limited solubility in water, some particulate disperse dye may occlude to the fiber surface after the dyeing phase is complete. Excess dye on fiber surfaces results in adverse results such as reduced wet-fastness, wash-fastness, sublimation and dry cleaning fastness as well as dulling of shade.
[0009] The usual practice for removing unwanted dyes is called reduction clearing and uses a bath of caustic soda and sodium dithionite and a surfactant. The ease of removal varies from dye to dye and in some cases the dye is only partially reduced and results in a dull color.
[0010] Ozone is a powerful oxidizing agent which in many cases destroys the chemical structure of the dye so as to make it soluble or completely decolorizes the dye.
[0011] Unwanted dye is not only found on fabrics or yarns but can occur when equipment is used for multiple tasks or to run different dye batches. Deposited or excess dye is difficult to remove from washers or other equipment because it can enter different cracks or crevices in the washer or other equipment or to appear later during a run of a different dye batch. It would be advantageous to be able to dissolve and remove or decolorize the residual dye before beginning another operation in the washer or in other textile working equipment.
SUMMARY OF THE INVENTION
[0012] The present invention relates to a process for simultaneously mercerizing and selectively decolorizing a colorant on the surface of post mercerized dyed textile goods and/or the colorant within the fibers. The process comprises treating the textile goods in an alkaline bath with ozone for a period of time to decolorize or remove the colorant from the surface of the textile or to cause substantial decolorization.
[0013] Advantageously, the ozone is put into the treating bath as ozone gas or diluted with an inert gas or air.
[0014] The process can be utilized to prevent redeposit of dye which has been left in the bath because of a previous dyeing process or to pre-treat the bath prior to the addition of the textile goods.
[0015] It is therefore an object of the invention to remove colorant from the surface of textiles without any substantial discoloration in the textiles or alternatively to decolorize and improve the texture and luster of the textiles.
[0016] It is a further object of the invention to prevent redeposit of colorants onto the surface of dyed textiles.
[0017] It is yet another object of the invention to remove colorant from the surface of synthetic textile surfaces and selectively decolorize to a desired degree.
[0018] It is still another object to treat a dye bath to destroy or decolorize any dye from a previous textile treatment which contains residues of previous dyes which may be redeposited onto the textiles.
[0019] It is understood that the terms “textile goods” and “textile substrates” relate to fibers, yarns, fabrics or garments.
[0020] It is also understood that the term “colorants” includes direct dyes, reactive dyes, disperse dyes and pigments which are commonly utilized in the dyeing or coloring of the textiles.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] In accordance with the invention there is provided a means for the selective removal and/or the decolorization of colorants on the surface of mercerized post dyed Textiles or also within the textile fibers while improving the hand of the textiles. This includes dyes which have been deposited from a previous fabric treatment process. More particularly the process involves the use of ozone in combination with a base to treat a textile in a bath at a temperature and for a period of time wherein only a dye or colorant would be selectively decolorized or removed as a result of the reaction with ozone and the hand of the textile would be improved. The temperature can be ambient or elevated depending upon the textile and the dye and the amount of ozone applied. The fabrics are subsequently neutralized.
[0022] Colorants of textiles comprise a large catalog of chemical structures. Some of these chemical structures can be oxidized to a soluble form, can be destroyed so as to be soluble or decolorized or to merely exist in a decolorized form.
[0023] For cellulosic mercerized and dyed textiles including denim, muslin, and chambray, containing azoic, basic, direct, mordant, oxidative, fiber reactive, sulfur, or vat dyes. For the bast fibers (line, flax, hemp, jute, ramie, etc.) acid, direct, fiber reactive, vat, and solubilized vat dyes are the one indicated.
[0024] In polyamide fibers such as nylon-6, nylon 6-6, and nylon 6-10, acid, disperse, mordant, pigment, and fiber reactive dyes are preferred for both background dyeing and selected redyeing. Disperse dyes and pigments are employed for polyester fabrics. For acrylic fibers such as Creslan RTM , Acrilan RTM , Orlon RTM , and Courtelle RTM , basic disperse and pigment dyes are best employed. Disperse colors are used for polyolefin fabrics. Basic and disperse colors are used for polyvinyl chloride fabrics. Elastomeric fabrics such as Lycra RTM may be dyed with acid, disperse, fiber reactive, and vat dyes. Interesting stylish effects can be generated with the process of the present invention for such fashion, elastomeric garments as women's swim wear.
[0025] Fiber-reactive dyes are preferred for those categories of fabric with which they can be used, as listed above, because they react with the substrate to form covalent chemical bonds, rather than dyeing by mere secondary forces or occlusion. Within the category of fiber-reactive dyes there are at least four classes. All four are available from PRO Chemical & Dye Inc. Somerset, Mass. 02726, a distributor. The MX series Sumbit Supra (DYSTAR) and Cibacron C (Ciba) are the most reactive and most versatile, comes in 43 colors, but has the shortest shelf life. These dyes set even at ambient temperature and can be easily selectively decolorized. The F series is slightly less reactive but has four times the shelf life. Higher dyeing temperatures of 41 degree-43 degree C. are recommended. The F series is the Cibacron F class of reactive dyes from Ciba, who are internationally known under the trade name of Ciba these days. Liquid reactive dyes from Clarinant Corp. are used best at 60 degree C. and are best set by steaming. The H series are available as both powder and liquids especially for printing and painting on natural fibers, such as cotton, wool and silk. The redyeing is done at 80 degree C. followed by steam setting at room temperature.
[0026] As a result of the different characteristics of the dyes and the temperatures which are required for the base and ozone to react, each textile must be pre-tested to determine the temperature and time of exposure to accomplish the effective or desired amount of removal or discolorization of the colorant or dye.
[0027] A large majority of disperse dyes are monoazo dyes of low molecular weight can be cleaned by ozone. Others have an anthraquinon structure which is difficult to reduce. Most direct dyes contain 4 to 7 aromatic rings and contain the azo chromophore as well as a sulphonate group. Direct black dyes comprise two or more colorants which form into disperse dyes. One form is of a combination of navy blue shaded with red or rubine and a yellow-brown or orange component.
[0028] As a result of the differences in chemical structures, in order to achieve the objects of the invention it is generally required to determine the type of dye or colorant that has been utilized in order to arrive at the proper parameters to mercerize and oxidize the colorants without affecting either the fibers. In the case of synthetic fibers such as polyesters, the dye within the fiber is slightly affected by the ozone and the ozone has little effect in degrading the fibers when it is desired to remove plated dye. The colorant or dye on the surface of the fiber is therefore exposed to the oxidation effects of the ozone for a reduced period of time.
[0029] Generally, temperatures between 50° and 120° F. preferably between 50° and 100° F. are sufficient to dissolve the oxidation components of the colorant or dye utilized. The elevated temperatures are required for the mercerization.
[0030] Cellulosic fibers because of the reactive dyes require higher temperatures, generally about 80°-120° F. Many dyes can also be treated at ambient temperatures with both the base or ozone.
[0031] Black dyes are an exception because most black dyes comprise more than one dye and care must be taken so as to decolorize only the surface dye which causes the discoloration when no discoloration in the fibers is required.
[0032] Combination of yarns formed with polyester and cotton fibers many times are dye plated at the twists of the fibers.
[0033] In accordance with one embodiment of the invention, ozone is produced according to U.S. Pat. Nos. 5,366,510 and 5,939,030 which are herein incorporated by reference for use either in a dye bath or after rinsing the dyed textile. Ozone may be used above or in combination with a gas, for example, air or dissolve in the bath. The ozone levels dissolved in the bath or treating liquid can be adjusted before the textile is placed in the bath so as to oxidize or destroy any residue in the bath which may plate onto the textile or the ozone can be added to the bath already containing the textile. Micro-processors can be used to monitor the system to maintain suitable concentrations dependent upon the application. Preferably, a sample of the dyed textile is pre-tested to determine the operating parameters for the temperature and the time of exposure to the ozone. No pre-testing is required when a washer or bath is pretreated to eliminate any residual colorants prior to treatment of the textiles.
[0034] Residence time in the ozonated bath is dependent upon the colorant or dye and the Type of fiber or textile structure. Generally for synthetic fibers about 3 to 5 minutes is required at temperatures at least 50° F. to 120° F. since only the plated dye or colorant is to be removed. Cellulosic fibers usually contain reactive dyes and temperatures about 100° F. for at least 3 minutes in a basic solution is required. Generally between 3 and 20 minutes depending upon the dye are required.
[0035] After treatment with the base and ozone the fabrics are neutralized with organic or mineral acid. Preferably, the acid is citric acid or acetic acid.
[0036] The base which is used is an alkali hydroxide, ammonium hydroxide or ammonium carbonate.
[0037] The treatment of the textile unlike the initial mercerization is in a relaxed state.
[0038] The bath contains about 0.5% to 15% of the base.
[0039] Without limitation, some of the preferred embodiments of this invention are set forth in the following examples.
Example 1
[0040] In a rotating washer-extractor containing 10 gallons of water containing 0.5% sodium hydroxide held at a temperature of 100° F. was bubbled ozone from an ozone generator. Three pounds of Fruit of the Loom 100% cotton knit pre-dyed with reactive black dye, and taken from the dye process before the first salt rinse was placed into the washer and tumbled with ozone bubbled therein for three minutes. The fabric was neutralized with 100 grams of citric acid in 10 gallons of water, extracted and dried.
Results
[0041] A crock test pursuant to AATCC method 8-1996 showed that the textile held shade and had a gray scale reading of 5. Only the surface was affected by the ozone. The process can be used in other equipment such as in jet dyeing.
Example 2
[0042] Following the procedure of Example 1, 3 yds. of the cotton knit were placed into the washer-extractor containing 10 gallons of water containing 0.5% sodium hydroxide with a bath temperature of 120° F. and with ozone being bubbled therein. The textile was tumbled for 8 minutes and then extracted and dried.
Results
[0043] The crock test showed a 5% loss of color and a gray scale reading of 5. The additional time appeared to be the factor for the loss of color within the fibers. There was an improvement in hand and luster.
Example 3
[0044] Following the procedure of Example 1, 3 yds. of the cotton knit were placed in the washer-extractor containing 10 gallons of water and 0.5% sodium hydroxide with a bath temperature of 120° F. and with ozone being bubbled therein. The fabric was tumbled for 20 minutes and then neutralized, extracted and dried.
Results
[0045] The crock test showed a 20% loss in color and a gray scale of 5.
[0046] The additional time was a factor in the loss of color.
[0047] The additional exposure resulted in the loss of color but greater hand and luster which was measured visibly.
[0048] The process can be used similar for yarn in package dyeing.
Example 4
[0049] Following the procedure of Example 1, 3 yds. of 100% polyester suede dyed with direct black were placed into the washer-extractor containing 10 gallons of ozonated water with 0.5% sodium hydroxide with a bath temperature of 65° F. and with ozone being bubbled therein. The fabric was tumbled for 45 minutes and then neutralized, extracted and dried.
Results
[0050] The crock test showed a 20% loss of color and the fabric had a green cast. The fabric had a gray scale measurement of 4.5-5.
[0051] The prolonged time resulted in the color loss of one of the dye components of the black dye.
Example 5
[0052] Following the procedure of Example 4, 3 yds. of 100% polyester suede fabric dyed black with direct dye were placed into a washer-extractor containing 10 gallons of Water with 0.5% sodium hydroxide at a temperature of 65° F. with ozone being bubbled therein. The fabric was tumbled 30 minutes, extracted and dried.
Results
[0053] The crock test showed a 10% loss in color with a gray scale of 4.5 to 5. The fabric had a blue cast which indicated one of the dye components was oxidized.
Example 6
[0054] Into each of three washer-extractors containing 10 gallons of water with 0.5% sodium hydroxide pretreated with ozone at 65° F. were placed 3 yds. of Morgan fabrics 100% polyester suede dyed with disperse black dye.
[0055] Sample 1 was tumbled 5 minutes, neutralized, extracted and dried.
[0056] Sample 2 was tumbled 10 minutes, neutralized, extracted and dried.
[0057] Sample 3 was tumbled 15 minutes, neutralized, extracted and dried.
Results
[0058] The crock test showed the following:
[0059] Sample 1 held the shade and had a gray scale of 3-4.
[0060] Sample 2 had a 5% color loss and a gray scale of 3-4.
[0061] Sample 3 had a 10% color loss and a gray scale of 3-4.
[0062] The fabric held its color on shorter exposure to ozone.
Example 7
[0063] Into each of three washer-extractors containing 10 gallons of water containing 5% sodium hydroxide were placed 3 yds. of Fruit of the Loom 100% cotton knit which were dyed with reactive black dye.
[0064] Ozone was bubbled into the washer-extractor.
[0065] Sample 1 was tumbled in a bath at 100° F. for 3 minutes, neutralized, extracted and dried.
[0066] Sample 2 was tumbled in a bath at 120° F. for 8 minutes, neutralized, extracted and dried.
[0067] Sample 3 was tumbled in a bath at 65° F., for 20 minutes, neutralized, extracted and dried.
Results
[0068] The crock tested showed the following:
[0069] Sample 1 held its shade and had a gray scale at 4.5.
[0070] Sample 2 had a slight color loss and a gray scale at 4.5.
[0071] Sample 3 had a 10% color loss and a gray scale at 5.
[0072] Time of exposure to ozone and not temperature was critical in loss of color for cotton.
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A process for removing dye and improving hand in cellulosic textiles utilizing a mercerizing ozone bath. The process also prevents redeposit of dye which is residual in a dyeing process. The time and temperature of the process is dependent upon the type of dye and the temperature the process is run. The process can be used in vat dyeing, jet dyeing, package dyeing and the like to obtain different shades of color while improving the hand and luster of the textile.
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CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from U.S. Prov. App. Ser. No. 60/868,512 filed Dec. 4, 2006, the entire contents of which are herein incorporated by reference. This application also claims priority from U.S. Ser. No. 11/758,651 filed Jun. 5, 2007 which in turn claims priority from U.S. Prov. App. Ser. No. 60/803,979 filed Jun. 5, 2006, the contents of each of which are also herein incorporated fully by reference.
FIGURE SELECTED FOR PUBLICATION
[0002]
FIG. 17
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The invention relates to footwear and a method of manufacturing same. In particular, the invention relates to a shoe construction having an outsole and upper of footwear stitched together along the forefoot area and glued together along the middle area of the footwear.
[0005] 2. Discussion of the prior art
[0006] The human foot is a combined structure of base and lever, supporting and balancing the body's weight while standing, as well as raising and moving the body. The anatomy of the foot is very complex, but well studied and well know to the shoe industry. Generally, footwear designers tend to construct shoe models that are both comfortable and durable. In addition, of course, the shoes have to be aesthetically appealing and follow the fashion trends.
[0007] When even one part of the foot becomes damaged, it can affect every other part of the foot and lead to problems. In very general terms, normal or neutral feet tend to roll off the center of the forefoot (front part of the foot). This motion is associated with substantial stresses upon the forefoot that gradually decrease as the foot rolls towards the heel. Accordingly, in use, if the shoe design ignores both the anatomical and mechanical particularities of the foot, the front of the shoe, if it is not sufficiently reinforced, may wear out rather soon and if not also well designed will appear unattractive. On the other hand, if the shoe has an overly rigid construction, it creates an uncomfortable environment for the foot.
[0008] One effort to streamline both the construction of the shoe design and secure the mechanical requirements of the shoe can be found in U.S. Pat. No. 5,203,792 to Kaiser, the entire contents of which are herein fully incorporated by reference. In Kaiser, there is provided a flexible shoe sole member having a lip member extending fully about the top surface. An upper member is then fit, right side in, about the sole such that the upper circumscribes the lip of the sole. Then the upper is secured to the outer wall of the lip and the inner wall of the lip is folded inward and the entire sole flipped right-side-out so as to present a desirable seam surface and a smooth juncture between sole and upper member. Unfortunately, this reference fails to recognize the variants and requirements within the design and construction fields as will be appreciated by one of skill in the art having considered the present disclosure in detail.
[0009] In summary, the problems of commercially available manufacturing methods for shoe gluing include at least the following:
[0010] Poorly constructed glue joints that easily separate.
[0011] Difficult to functionally adhere toe box constructions.
[0012] Delicate designs more suitably adapted to hand stitching construction techniques are costly and time consuming.
[0013] Non-adaptability of the present glue-joint and stitching construction techniques.
[0014] The design aspect is particularly important to consider for fashion conscious woman. Typically, the outsole of the shoe is stitched to the rest of the shoe parts so as to provide a reliable structure capable of withstanding high stresses during use. However, stitching may add to the overall unappealing and bulky look of the shoe and may well create discomfort in use, when stitching is rubbing on a foot portion. Furthermore, as a technological operation, the stitching may be time- and labor-ineffective.
[0015] A need therefore exists for footwear that has a reinforced front portion capable of withstanding high stresses while providing the footwear with elegance.
[0016] Another need exists for a shoemaking process that is time- and labor-effective.
SUMMARY OF THE INVENTION
[0017] The inventive footwear seam construction and method for manufacturing same meets these proposed needs and multiple variants are provided. In non-technical parlance the phase blind-seam may be employed or stitch and turn depending upon the feature of construction being discussed. In accordance with one aspect of the invention, the inventive method includes juxtaposing an upper with an outer surface of an outsole or with the outer surface of a member extending from tan outsole (attached by stitching, gluing, or other construction). The outsole may be made by a variety of molding methods and has an outer surface and an inner surface and may be generally planer in alternative aspects (as will be discussed). The outer surface is provided with a peripheral edge provided by extending the outer surface or by attaching a secondary outsole member or alternatively called a secondary upper portion. In the juxtaposed position also considered an inside-out position, the inner face of the peripheral edge and the forefront bottom portion of the upper overlap one another. Once the overlapping position is established, the upper is turned upside down over the periphery of the outsole and ends up facing the inner surface of the outsole.
[0018] In brief summary, a footwear member is optionally configured with an outer sole and an upper coupled together so as to define a forefoot area of and a rearfoot area of the footwear member. An extending lip member couples the outer sole and the upper member and may extend from either one forming a non-visible or blind seam construction that may be further manipulated in multiple ways. The extending lip member or connection member are stitched together along a forefoot area of the assembled footwear and may optionally allow a portion of a tread member to be glued along a rearfoot area of the assembled footwear. The assembly presented enables optional construction techniques adaptable to a variety of fashion construction options.
[0019] In accordance with one aspect of the invention, the forefront bottom region of the upper and the peripheral edge of the outsole are then stitched together but may be adhered in other manners without departing from the scope and spirit of the present invention. As mentioned above, the forefront portion of footwear is always under substantial flexing forces generated by the foot motion of the footwear owner as he or she walks forward. Accordingly, the forefront area of the footwear, which is generally defined by the stitched forefront bottom portion and peripheral edge, provides a reliable structure capable of withstanding the flexing forces as constructed according to the alternative details noted below.
[0020] During the stitching step, the peripheral edge and forefront bottom portion of the upper are bent inwards to extend substantially parallel to the inner surface. The stitches may penetrate through to the outer surface of the outsole or the extending flange of the secondary upper where thin-layer constitution requires through stitching, however, where permissible by the layer-thicknesses involved the stitching do not penetrate through the outer surface of the outsole preserving, thus, waterproof characteristics of the flexible polymeric material. Alternatively, the stitching may be replaced by thermal bonding, adhesive-bonding, or other known systems to provide a waterproof seam.
[0021] In accordance with another aspect of the invention, the stitching may penetrate a portion of the outsole. In still a further aspect of the invention, the stitched parts of the footwear may be bonded with the inner surface of the outsole. Importantly, regardless of the type of the coupling, the exterior of the forefront area, which is located immediately next to the outsole, does not protrude laterally beyond the periphery of the outsole thereby rendering the forefront area of the footwear elegant and appealing to the eye.
[0022] The method continues with tucking the rearfoot bottom portion of the upper so that it lies atop the inner surface of the outsole. In accordance with a further aspect of the invention the bent portion is then glued to the outsole's inner surface. Since the rearfoot area of the footwear is exposed to insignificant bending or flexing forces, gluing the outsole to the upper establishes a reliable stress-resistant structure. To meet aesthetic requirements, the surface of the upper, which is immediately adjacent to the bent rearfoot bottom portion, like the forefront bottom portion, does not protrude laterally beyond the periphery of the outsole the inner to the bet portion. Accordingly, both the forefoot and rearfoot bottom portions of the upper substantially conform to the outer contour of the outsole. The footwear manufactured in accordance with the invention is aesthetically appealing, has a reliable structure that takes into consideration the anatomical particularities of the human foot and cost-effective.
[0023] These and other features and aspects of the present invention will be better understood with reference to the following description, figures, and appended claims.
BRIEF DESCRIPTION OF THE FIGURES
[0024] FIG. 1 illustrates an exploded view of an alternative aspect of the inventive footwear.
[0025] FIG. 2 illustrates a top view of an outsole and upper in a disassembled state of the inventive footwear.
[0026] FIG. 3 illustrates an initial position of the upper and outsole of the inventive footwear in accordance with the alternative initial step of one aspect of the inventive method, in which the upper is juxtaposed with the outer surface of the outsole or an extended portion affixed to and extending from the outsole.
[0027] FIG. 4 illustrates a subsequent step of the inventive method in which the forefront bottom portion of the upper is stitched the outsole and inverted or turned inside-out so that the upper faces the inner surface of the outsole.
[0028] FIG. 5 illustrates a following step of the inventive method in which the rearfoot bottom portion of the upper is inverted to the right-side-out configuration so as to face the inner surface of the outsole.
[0029] FIG. 6 illustrates a following step of the inventive method in which the rearfoot bottom portion of the upper is glued to the outsole.
[0030] FIG. 7 illustrates the inventive footwear in the assembled state thereof.
[0031] FIG. 8 is a side view of a shoe constructed according to an alternative aspect of the present invention.
[0032] FIG. 8(A) is a sectional view through line I-I in FIG. 8 .
[0033] FIG. 8(B) is an enlarged view of Area A in FIG. 8(A) .
[0034] FIG. 8(C) is a partial view of a base member and an upper portion in a blind-seam connection position prior to turning and later constriction.
[0035] FIG. 9 is a sectional view through line II-II in FIG. 8 .
[0036] FIG. 10 is a plan view of a flexible tread or sole member optionally containing a tread pattern (not shown).
[0037] FIG. 11 is a plan view of a separate flexible tread lip or upper lip member that is later connected between the flexible tread or sole members and an upper member.
[0038] FIG. 11(A) is a plan view of a stitched together or connected assembly between the flexible tread or sole member in FIG. 10 and the separate flexible tread lip or upper lip member in FIG. 11 .
[0039] FIG. 12(A) is a plan view of a stitched together upper member containing a tongue portion.
[0040] FIG. 12(B) is a partially folded-over or juxtaposed plan view of the stitched together upper member of FIG. 12(A) .
[0041] FIG. 13 is a side elevational view of the pre-assembly of FIG. 11 and FIG. 12(A) prior to juxtaposition, flipping, or inversion by both members to form FIG. 14 .
[0042] FIG. 14 is a side elevational assembly view of the juxtaposed, flipped, or inverted assembly of the separate flexible lip member and tread/sole in FIG. 11 with the inverted upper assembly in FIGS. 12(A) and 12(B) .
[0043] FIG. 15 is a side elevational view of the assembly in FIG. 14 , rejuxtaposed or flipped right-side-out exposing the tread member with the insertion of an insole portion.
[0044] FIG. 16 is a side elevational view of the assembly of FIG. 15 in combination with an external foot-shaped last member to provide a rigid support for later assembly steps.
[0045] FIG. 17 is a side elevational view of a complete assembly combining the assembly of FIGS. 15 and 16 , with a heal body.
DETAILED DESCRIPTION
[0046] Reference will now be made in detail to a sequence of inventive steps illustrating manufacturing of the inventive footwear in accordance with the inventive method. The drawings are in simplified form and are not to precise scale. For purposes of convenience and clarity only, directional terms, such as top, bottom, left, right, up, down, over, above, below, beneath, rear, front and beyond may be used with respect to the drawings. These and similar directional terms should not be construed to limit the scope of the invention in any manner. The words “connect,” “couple,” and similar terms with their inflectional morphemes do not necessarily denote direct and immediate connections or particular methods of connecting, unless specifically identified, but also include connections through mediate elements or devices.
[0047] In coping with the problems noted above, the present invention provides a system for manufacturing footwear, particularly ladies shoes that combines a stitch and turn method utilized by this invention and a conventional glue construction.
[0048] Referring to FIGS. 1-6 , and in particular to FIG. 1 , an inventive footwear 10 is configured with a outsole 12 , upper 14 , midsole 16 , insole 18 and heel 42 . Each of the above-identified parts has a forefront portion extending from the front end of the footwear and terminating substantially midway between the front and rear ends of the footwear. Portions of footwear components extending from the midsection to the rear end of the footwear are generally denoted as rearfoot portions. Coupled together, the forefront portions and rearfoot portions of the footwear components define a forefront area 20 and rearfoot area 22 , respectively, of footwear 10 ( FIG. 7 ).
[0049] During construction, upper 14 is initially juxtaposed with an outer surface 24 of outsole 12 ( FIGS. 3 and 4 ) and subsequently stitched thereto ( FIGS. 3 and 4 ). The stitching step is accomplished by juxtaposing, turning, flipping the upper with the outsole so that a bottom edge 32 of a forefoot bottom portion 44 ( FIGS. 1 , 3 and 4 ) overlaps an outer face 48 ( FIG. 3 ) of a peripheral flange 28 of outsole 12 . The flange 28 is formed on inner surface 26 of outsole 12 and defines its outer extremity while extending along the forefront portion of the outsole or optionally a greater or lesser portion of the outsole (or as will be discussed an alternative portion of the upper that is affixed separately, as will be discussed). As a result of molding, peripheral flange 28 extends transversely to inner surface 26 rendering positioning of upper 14 labor- and time-effective.
[0050] Having juxtaposed upper 14 and outer surface 24 of outsole 12 in the desire position, the overlapped segments of flange 28 and forefront peripheral edge 32 are stitched together, as better illustrated in FIG. 4 . Then, upper 14 is inverted so as to face inner surface 26 of outsole 12 , as shown in FIG. 4 .
[0051] Thereafter, a rearfoot peripheral portion 46 is bent inwards so that its edge 34 ( FIG. 3 ) lies atop inner surface 26 of outsole 12 . To completely couple the outsole and upper, a layer of glues is inserted between the opposing surfaces of the upper and outsole. Inserting a weight 40 or foot-last (a rigid foot-shaped body) ( FIG. 6 ) and pressing there against so that it, in turn, brings the opposing surfaces to be glued in close contact with one anther complete the coupling step. Accordingly, the outsole/upper combination is characterized by the stitched forefoot area 20 of footwear 10 and its glued rearfoot area 22 . The variously coupled forefoot and rearfoot areas of the footwear allow it to withstand greater stresses usually imposed on the forefront area, while leaving the rearfoot area sufficiently reinforced to withstand relatively insignificant stresses during the use of the footwear. On the other hand, the gluing operation, as compared to the stitching operation, is time-effective which renders the entire coupling step of the inventive method to be time-effective as well.
[0052] Completion of the method entails providing a compartment, which is formed as a result of coupling between the upper and outsole, with midsole 18 that is, typically, made from rigid material such as wood, cork, plastic or even metal. The midsole spans the width of the outsole and, thus, is configured as a stiffening member preventing unintended distortion of the forefront area of footwear 10 during shipping and use.
[0053] After the midsole is placed atop the inner surface of outsole 12 and attached parts of upper 14 , it is fixedly attached thereto so as to prevent relative displacement between the midsole and the rest of coupled components. To soften the supporting structure of the footwear, a cushioned insole 16 is removably inserted into the compartment atop midsole 18 . Finally, a heel 42 is attached to the rearfoot portion of the outer surface of outsole 14 .
[0054] The final product is thus is manufactured by a simple, time- and cost-effective blind seamed process involving in part a turning process benefited by a highly flexible outsole and upper portions. In addition, footwear 10 is elegant because not a single area of the upper protrudes beyond the periphery of the outsole, as will be evidenced during the rest of the disclosure.
[0055] As mentioned above, the molded outsole is made with flange 28 extending inwardly from and transversely to inner surface 26 of outsole 12 . The forefront bottom portion 44 of upper 14 is juxtaposed with outer face 48 of flange 28 and stitched to this flange. When these parts are subsequently flexed toward the inner surface of outsole 12 , the bottom region of upper 14 adjacent to its edge 32 of forefront area 20 does not extend laterally beyond the periphery of outsole 12 , thereby providing the forefront area of the footwear with an elegant look.
[0056] The rearfoot portion 46 of upper 12 extending along the midsection of the footwear is wider than its forefoot portion 44 and has respective portions of its bottom edge 34 tucked inside so that the rearfoot portion of the upper also does not extend laterally beyond the periphery of outsole 12 . Like the forefoot area, the rearfoot area is, thus, elegant, but both the forefoot and rearfoot areas are still sufficiently reinforce to withstand respective stresses upon the footwear.
[0057] The inner surface 26 of outsole 12 has an elevated region 36 ( FIG. 2 ) having its periphery spaced from an inner face 50 of flange 28 . Thus, opposing sides of the elevated region and flange delimit a trough 38 coextending with flange 28 . The trough 28 is dimensioned to receive the full width of flange 28 and, of course, edge 32 of upper 14 , when these parts get stitched. Preferably the depth of the trough is sufficient to receive the stitched parts so as to have edge 32 of upper 14 , which upon bending forms an outer layer of the stitched parts, flush with the top surface of the elevated region. Thus, the inner surface of footwear 10 supporting the midsole and insole 18 and 16 ( FIG. 1 ), respectively, is substantially flat and provides the owner of the footwear with a comfort. The stitched parts may be glued to the trough during gluing of the rearfoot portions of the upper and outsole. Alternatively, the stitching may be extended into the outsole without, however penetrating the full width thereof.
[0058] The footwear 10 , as illustrated in FIGS. 1-7 is shown to be designed for women, and, thus, the elegance of the footwear is particularly important. However, the same method and structure may be implemented for manufacturing footwear for men and children. The insole 16 , often constructed of natural or synthetic leather is positioned on foam cushion. Commonly an adhesive glue, often a clue compatible with a PVC based outsole 12 , is used between the outer and midsole 12 , 18 , respectively.
[0059] Materials used for manufacturing upper 14 can vary in accordance with any given design, but, preferably, the upper is made from leather.
[0060] Referring now to FIGS. 8 through 9 an alternative construction discussion is present according to another aspect of the present invention.
[0061] A shoe 100 includes a toe portion 200 and a heal portion 300 joined by a continuous sole portion 500 as shown and supported by a heal member 400 . A series of decorative cutouts 60 , 60 enhance the visual appearance of shoe 100 . Sole member 500 is constructed of PVC (polyvinyl chloride), but may be constructed from any suitable material both organic (leather/rubber) and in-organic/man-made (PVC and related elastomeric materials).
[0062] Referring now more directly to FIG. 8A-9 , toe portion 200 includes a of sole member 500 stitched at extending lip members 140 to upper member portion 90 in a type of blind-seam, as will be discussed. In this embodiment, uppers 90 are joined by upper members 110 , 110 at decorative stitchings 111 , 111 , as shown to enhance an overall attractive appearance. In alternative embodiments, upper 90 in upper member 200 may be continuous from side to side or otherwise alternatively constructed according to the related arts. A pair of opposed stitches 116 , 116 on each extending lip member 140 securely join bottom portions of uppers 90 as shown. Sole member 500 additionally includes tread portions 70 for gripping during walking and for enhancing flexibility as desired.
[0063] A stiffening member or insole support board member 80 is generally provided for additional support and spans generally the width of sole member 500 to provide stiffening support and prevent unintentional distortion of toe portion 200 during shipping and later use. Stiffening member 80 is inserted after the blind-seam stitching process as the flexibility required to achieve the same prevents prior insertion of stiffening member 80 .
[0064] A foam cushion member 112 is positioned on insole support board member 80 , as shown and increases user comfort. An insole member 113 , often constructed of natural or synthetic leather is positioned on cushion member 112 and provides a pleasing visual appearance. Commonly, an adhesive glue 115 , often a glue compatible with a PVC based sole member 500 , is used between the layers to secure each respective layer to sole member 500 and insole support board 80 , and is used as would be otherwise expected by one of skill in the art having read and considered the entire disclosure. In this way, the respective members are secured and shoe 100 is provided in a suitable form for secure consumer use. This construction also is adapted to bind extending lip 140 to respective locations on sole 500 securely locking stitchings 116 in place while providing a pleasing blind-seam outward appearance.
[0065] While not mandated by the present construction, alternative variants are envisioned by the present disclosure as noted in expanded view A in FIG. 8(A) , an additional adhesive layer 115 ′ is positioned between stitched or bonded portions of upper member 90 and extending lip members 140 to improve security.
[0066] Referring additionally now to FIG. 8(C) a portion of sole member 500 is shown with an extending lip member 140 stitched to upper 90 in a blind seam manner prior to a turning and optional gluing. It will be understood by those of skill in the art that variants of the present invention are within the bounds of the present disclosure, including those variants wherein lip members 140 are provided as separate members, or the stitched portion of upper 90 is provided in a separate upper or separate lip member body, as will be discussed without departing from the scope and spirit of the present invention.
[0067] Referring now directly to FIG. 9 , heal portion 300 of shoe member 100 is more fully discussed. As shown, sole member 500 is joined to upper 90 employing adhesive 115 . Thereafter, insole support board member 80 ′ (which may be an extension of support board member 80 ) is positioned and secured allowing later insertion of a reinforcing metal shank member 117 bounded by support board members 118 , 118 on either side. Thereafter, foam member 112 (likely a closed cell based foam) is layered with insole member layer 113 and adhered in place using adhesive 115 (not shown). Finally, heal member 400 is secured to the bottom portion of sole 500 to complete construction.
[0068] In another manufacturing method discussed, after toe portion 200 is constructed and flipped/inverted (creating a joining or stitching method creating a blind seam), heal portion 300 of shoe 100 is constructed by inserting an external last (shown later) to form a foot-shape and gluing the insole board in place and thereafter finishing and polishing the shoe in a conventional manner. In this way, an alternative embodiment of the present invention provides both a blind-seam construction method for a portion of a shoe construction and a partial stitch-and-turn construction method for a second portion of a shoe construction without departing from the scope and spirit of the present invention.
[0069] Referring collectively now to FIGS. 10 through 17 an additional alternative seam construction method employs a lip extending member is provided in assembly 600 . Shoe assembly 600 includes a flexible tread member or sole member 601 that may be optionally formed with treads or friction enhancing protuberances or flexibility enhancing undulations (both not shown) so as to enable use as a shoe tread or sole member while being sufficiently flexible to enable the proposed method of assembly as outlined the proposed invention.
[0070] A separate flexible tread lip or upper lip member 602 is provide in a shape partially extending about a corresponding portion of tread member or sole member 601 , and is shown in a generally “U” or “N” configuration ( FIG. 11 ). It is noted, that the proposed alternative flexible tread lip or upper lip member is functional to flexibly join portions of the flexible tread or sole members 601 and an upper member assembly 603 (as will be discussed), and may be a wholly separate member prior to assembly, may alternatively extend from an upper member assembly 603 or may alternatively extend from flexible tread or sole member 601 according to aspects of the present invention without departing therefrom as will be recognized by those of skill in the art having considered the entire disclosure herein.
[0071] As will be noted in FIG. 11A , flexible lip member 602 is connected with flexible tread member 601 with partial perimeter or edge stitching 800 (as shown) but may be connected in any other known bonding, adhering, or affixing method known to those in the shoe construction arts without departing form the scope of the present invention. A toe region 602 A of the lip-tread assembly 602 B is opposite a lose heal region 602 C of tread or sole member 601 that is not connected to tread or sole member 601 , as shown. A loose portion 609 opposite toe region 602 A is provided where connection 800 ends for the remaining portion of flexible lip member 602 .
[0072] Referring directly to FIGS. 12(A) and 12(B) an upper assembly 603 contains a continuous upper loop 604 joined along seam 605 . Continuous upper loop 604 contains a toe portion 604 A and a heal portion 604 B including seam 605 . An upper tongue portion 605 A is joined or connected to continuous upper loop 604 in toe portion 604 A in a stitching region 606 or by other connection methods known to those of skill in the art. To invert or juxtapose upper assembly 603 an operator grasps continuous upper loop 604 proximate rear seam 605 and twists along direction arrows 607 and 607 A in FIGS. 12A and 12B until ultimately upper assembly 603 is juxtaposed or inverted as will be understood by those of skill in the art.
[0073] It will be noted that the top plan view in FIG. 12A is represented in the top part of the view in FIG. 13 prior to the juxtaposition or inside-out switch for assembly in FIG. 14 .
[0074] In FIG. 13 a relationship is recognized prior to juxtaposition or inversion of both upper assembly 603 and lower assembly 602 A noting the general alignment of a stitching or connection interface between connection edges 608 , 608 on respective upper assembly 603 and lower assembly 602 A. It will be recognized by study of the image that non-connected portion 602 C of tread or sole member 601 includes a loose region 609 opposite toe portion 602 A.
[0075] In FIG. 14 , both upper assembly 603 and lower assembly 602 B have been juxtaposed or inverted or turned inside-out and are brought into close association along edges 608 and affixed or connected together by stitching 610 or by other methods known to those of skill in the art, such as thermal bonding, adhesive bonding, and combinations thereof. It will be appreciated by those of skill in the art that the surfaces visible in FIG. 14 are what would be the inner surfaces of the complete shoe assembly 600 ( FIG. 17 ) and that the view is of what would be considered an inside-out view.
[0076] It will also be appreciated by those of skill in the art having studied the present disclosure that flexible tread portion 601 is hidden from view and is within the inverted assembly, with it's surface-contacting tread portion (if any) facing the outer finished surface 605 A′ of tongue member 605 A. As connected along edges 608 by stitching or otherwise, it will be recognized that upon further juxtaposition or inversion the connection will be a blind seam or hidden-from view seam similar to that shown earlier in FIGS. 8(A)-8(C) , although unlike FIGS. 8(A)-8(C) the lip extension portion is not re-joined to the tread or sole member in a further assembly step.
[0077] In FIG. 15 , the assembly noted in FIG. 14 is re-juxtaposed or turned right-side-out again hiding seam edges 608 joined by connection 610 forming a type of partial blind-seam between the upper assembly and lower assemblies, as shown. As will also be appreciated, the non-connected portion 602 C of tread or sole member 601 remains non-connected. As shown an inner rigid foot support member 611 is inserted and in FIG. 16 is followed by insertion of a rigid foot-shaped last member 612 inside the assembly. Thereafter, adhesive (not shown) is employed to join portions of continuous upper member 603 proximate unsealed tread or sole portion 602 C along adhesive or connection juncture 613 forming a continuous connection between upper assembly 603 and lower assembly 602 B with lip member 602 there between having a blind seam 610 for by a blind seam or seam creation system or method.
[0078] In FIG. 17 heal member 615 is assembled in a manner recognized by those of skill in the shoe assembly arts involving pressure and adhesive to form full shoe embodiment 600 employing the present alternative embodiment of the present invention. It will be recognized by those of skill in the art that multiple connection methods (including stitching, bonding, and adhesive) may be employed to form the connections discussed herein without departing from the scope of the present invention.
[0079] In the claims, means- or step-plus-function clauses are intended to cover the structures described or suggested herein as performing the recited function and not only structural equivalents but also equivalent structures. Thus, for example, although a nail, a screw, and a bolt may not be structural equivalents in that a nail relies on friction between a wooden part and a cylindrical surface, a screw's helical surface positively engages the wooden part, and a bolt's head and nut compress opposite sides of a wooden part, in the environment of fastening wooden parts, a nail, a screw, and a bolt may be readily understood by those skilled in the art as equivalent structures.
[0080] It will be understood that the invention may be embodied in other specific forms without departing from the spirit or central characteristics thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive, and the invention is not to be limited to the details given herein.
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A footwear member is configured with an outer sole and an upper coupled together so as to define a forefoot area of and a rearfoot area of the footwear. An extending lip member couples the outer sole and the upper member and may extend from either one forming a non-visable or blind seam construction that may be further manipulated in multiple ways. The extending lip member or connection member are stitched together along a forefoot area of the assembled footwear and may optionally allow a portion of a tread member to be glued along a rearfoot area of the assembled footwear. The assembly presented enables optional construction techniques adaptable to a variety of fashion construction options.
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