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FIELD OF THE INVENTION
This invention relates to drainage bag assemblies, such as ostomy bags, for receiving bodily waste, and more particularly to an ostomy bag containing a removable inner liner.
BACKGROUND OF THE INVENTION
Ostomy bags for receiving bodily waste from colostomy and ileostomy patients are well known. One of the problems faced by users of ostomy bags, particularly colostomy bags, is how to dispose of the contents of the bag.
Many known forms of ostomy bag are made from materials that are not biodegradable and are not easily flushed down a W.C. (that is, a toilet) because of, for example, the buoyancy and relative bulk of the bags. With non-flushable bags, it has been common practice to cut an edge of the bag and then deposit the contents of the bag in the W.C. for flushing away, leaving the soiled bag for separate disposal, e.g. by incineration or by wrapping and placing in a waste bin.
One solution to this problem has been to provide ostomy bags made from materials that are capable of being flushed down a W.C. and examples of such bags are disclosed in WO 94/12128; EP 0259184; US 2004/0059306; EP 0320895; U.S. Pat. No. 5,989,235; GB 2083762; EP 388924; GB 2227668; GB 2193925; and WO 2007/085803.
In many cases, the flushable ostomy bag comprises an inner bag which is formed from a material that disintegrates or dissolves in water or is otherwise disposable and a protective outer bag formed from a material that is resistant to water. The outer bag can be constructed so as to be reusable several times, means being provided for opening the outer bag to permit removal and replacement of the inner bag or liner. The outer and inner bags may both be attached, directly or indirectly, to an adhesive flange which comprises a layer of a bio-compatible adhesive such as a hydrocolloid adhesive to secure the ostomy bag to the body of the patient about the stomal opening.
US 2004/0059306 in particular describes several forms of construction of two piece ostomy bags in which the inner bag or liner is replaceable and a re-fastenable opening is provided in the outer bag to give access to the inner bag so that it can be replaced.
U.S. Pat. No. 5,785,695 (Alcare) discloses ostomy appliances comprising inner and outer bags that are releasably attached to an adhesive flange by means of mechanical couplings comprising coupling rings having annular grooves that engage corresponding annular rims on the adhesive flange to form snap-fit connections.
US 2003/0153883 (Hansen) discloses ostomy appliances comprising an adhesive flange to which is secured a first mechanical coupling ring for the attachment of an outer bag. An inner bag or liner can also be secured to the first mechanical coupling ring by means of a second mechanical coupling ring which encircles the mouth of the inner bag and which forms a snap-fit connection against the radially inner surface of the first mechanical coupling ring.
A problem with ostomy appliances employing coupling rings to connect the inner and outer bags to an adhesive flange is that the coupling rings almost invariably make the appliance stiffer and less flexible and hence less comfortable to wear. In addition, where the coupling rings for the inner and outer bags are placed relatively close together, this can make separation and replacement of the bags difficult, particularly for people with impaired or reduced manual dexterity. A further problem with using coupling rings is that they will need to be removed prior to disposal of an inner bag down a WC. Not only does this add an additional potentially awkward step to the removal and disposal process but it may also result in the user's hands coming into contact with fecal waste at the mouth of the bag.
As an alternative to using mechanical couplings, adhesive bonding has been used to secure the inner and outer bags to the adhesive flange. Examples of ostomy bags making use of adhesive bonding can be found in U.S. Pat. No. 5,865,819 (Hollister) and WO 2004/082452 (Coloplast). U.S. Pat. No. 5,865,819 discloses an arrangement in which the inner and outer bags each have their own separate adhesive flange for direct connection to the body of the patient.
WO 2004/082452 discloses ostomy bags comprising an adhesive flange for attachment to the body of a patient, and inner and outer bags. The inner and outer bags are each provided with adhesive rings for attachment to the adhesive flange. In the preferred ostomy bag constructions disclosed in WO 2004/082452, the outer diameter of the adhesive ring of the inner bag is larger than the inner diameter of the adhesive ring of the outer bag and hence there is overlap between the two adhesive rings.
WO 2007/085803 discloses an ostomy bag assembly comprising inner and outer bags secured to an adhesive flange.
SUMMARY OF THE INVENTION
The present invention provides an ostomy bag assembly comprising outer and inner bags secured to one side of a flange; wherein:
the flange comprises a polymeric backing film and a layer of bioadhesive for securing the ostomy bag assembly to the body of a patient;
the flange has means defining an orifice to enable bodily waste to be received by the inner bag;
the outer bag is detachably bonded to a first attachment zone on the polymeric backing film of the flange by means of an annular bonding element which is interposed between the outer bag and the first attachment zone;
the inner bag is secured to a second attachment zone on the polymeric backing film of the flange;
the first attachment zone surrounds the second attachment zone and is non-overlapping therewith;
the second attachment zone surrounds the means defining the orifice;
the annular bonding element is formed from a multilayer polymeric material comprising first and second ethylene vinyl acetate layers and a polymeric support layer interposed therebetween;
the first ethylene vinyl acetate layer has a coating of an ethylene vinyl acetate copolymer adhesive thereon; and
the first ethylene vinyl acetate layer is bonded to the polymeric backing film of the flange by means of the coating of ethylene vinyl acetate copolymer adhesive, and the second ethylene vinyl acetate layer is welded to the outer bag.
Particular and preferred embodiments of the invention are as set out in the claims appended hereto or in the paragraphs below.
The polymeric backing film comprises a layer of polyurethane film. Preferably, the polymeric backing film consists of a single layer of polyurethane film. The annular bonding element is formed from a multilayer polymeric material comprising first and second ethylene vinyl acetate layers and a polymeric support layer interposed there between. The multilayer polymeric material is typically a coextruded film.
The polymeric support layer is selected from polymers that are compatible with ethylene vinyl acetate (EVA) (for example, can form a strong bond to the EVA during the coextrusion process) and which are typically of greater tensile strength than EVA. For example, the polymeric support layer may be a polyamide or an ethylene/methacrylic acid co-polymer or an ionomeric form thereof. A particular example of a material suitable for use as the polymeric support layer is Surlyn® (partially neutralized ethylene acid copolymer).
The total thickness of the multilayer polymeric material can be, for example, from 120 micrometers (μm) to 180 μm, more typically from 140 μm to 160 μm, for example approximately 150 μm.
A particular example of the multilayer polymeric material is the PerfecSeal® coated PerfecFlex® medical forming film (partially neutralized ethylene acid copolymer laminated with EVA) available from Perfecseal Limited of Londonderry, Northern Ireland, UK, or its equivalent.
The coating of ethylene vinyl acetate copolymer adhesive on one side of the annular bonding element is bonded to the polyurethane film. Preferably, the bond to the polyurethane film is achieved by means of heat sealing by the application of heat and light pressure using an appropriately shaped heat sealing tool. By way of example, a temperature of about 120 degrees C. to about 160 degrees C. may typically be applied for a period of about 2 to about 5 seconds.
When the annular bonding element is formed from a multilayer polymeric material comprising first and second ethylene vinyl acetate layers and a polymeric support layer interposed therebetween, one of the EVA layers is coated with the ethylene vinyl acetate copolymer adhesive and the other EVA layer is uncoated. The uncoated layer is bonded to the outer bag, for example by means of welding, for example, RF welding.
Preferably, the outer bag is formed from a multilayer polymeric film comprising a layer of ethylene vinyl acetate and a layer of polyvinyl dichloride or polyvinyl chloride, the ethylene vinyl acetate layer being bonded to the uncoated EVA layer of the annular bonding element. More preferably the outer bag is formed from a multilayer polymeric film comprising two layers of ethylene vinyl acetate with a layer of polyvinyl dichloride sandwiched there between.
The bond between the annular bonding element and the first attachment zone on the polymeric backing film of the flange is peelable, for example, the annular bonding element and the attached outer bag can be peeled away from the flange using only manual force. Once the outer bag and annular bonding element have been peeled away from the polymeric backing film, it is typically not possible to reattach them to the polymeric backing film by finger pressure alone as the ethylene vinyl acetate copolymer adhesive does not retain any adhesive capability at ambient temperature after the two surfaces to which it is bonded have been peeled apart.
In order to assist the annular bonding element and attached outer bag to be peeled away from the polymeric backing film of the flange, the annular bonding element may be provided with one or more tabs. The (or each) tab may be formed from a polyethylene foam material.
The material from which the outer bag is formed typically is substantially impermeable to flatus gases and in particular the noxious components of flatus gases. Preferably therefore, in order to prevent the build up of flatus gases inside the ostomy bag assembly, the outer bag is provided with a flatus gas vent opening covered by a filter, which permits gases to exit the bag but filters out malodorous and noxious gases. Such filters are well known and need not be described here.
In the drainage bags of the invention, the attachment zones for the inner and outer bags do not overlap, and, in this respect, the bags differ from the ostomy bags disclosed in US 2004/0059306 and WO 2004/082452, where the attachment zones for the inner and outer bags are shown as overlapping. In the bags of the present invention, the first and second attachment zones may be contiguous or they may be spaced apart. Preferably, they are spaced apart.
The inner bag is secured by means of adhesive to the second attachment zone on the flange. The adhesive may be, for example a pressure sensitive adhesive or a non-pressure-sensitive adhesive. The adhesive can be located on the second attachment zone, or on a ring surrounding the mouth of the inner bag, or on both. In one embodiment, the inner bag is provided with a ring of adhesive surrounding the mouth of the bag.
The inner bag may be formed from a non-disposable waterproof material of a type described above for the outer bag, but preferably the inner bag is formed from a material that is biodegradable or disposable, such as polyvinyl alcohol. For example, the inner bag can be formed from a polymer, such as polyvinyl alcohol, of a type or grade that is slowly soluble in cold water but is more soluble in hot water. Examples of types of polyvinyl alcohol suitable for use in the fabrication of inner bags or liners are described in our earlier application WO94/12128.
In one embodiment, the inner bag comprises an inner layer formed from a hot water soluble grade of polyvinyl alcohol and an outer layer formed from a non-woven tissue comprising cold water-soluble polyvinyl alcohol fibres and water-insoluble polymer fibers (for example, cellulosic or modified cellulosic fibres such as rayon fibers). The inner and outer layers are preferably secured together at their peripheries.
In another aspect, the invention provides a process for manufacturing an ostomy bag assembly comprising outer and inner bags secured to one side of a flange; wherein:
the flange comprises a polymeric backing film, a layer of bioadhesive for securing the ostomy bag assembly to the body of a patient, and a removable protective layer covering the layer of bioadhesive;
the flange has means defining an orifice to enable bodily waste to be received by the inner bag;
the outer bag is detachably bonded to a first attachment zone on the polymeric backing film of the flange;
the inner bag is secured to a second attachment zone on the polymeric backing film of the flange by means of a pressure sensitive adhesive;
the first attachment zone surrounds the second attachment zone and is non-overlapping therewith;
the second attachment zone surrounds the means defining the orifice;
the first attachment zone is defined by an annular bonding element which is formed from a multilayer polymeric material comprising first and second ethylene vinyl acetate layers and a polymeric support layer interposed therebetween;
the first ethylene vinyl acetate layer has a coating of an ethylene vinyl acetate copolymer adhesive thereon;
and wherein the first ethylene vinyl acetate layer is bonded to the polymeric backing film of the flange by means of the coating of ethylene vinyl acetate copolymer adhesive, and the second ethylene vinyl acetate layer is bonded to the outer bag;
which process comprises, or comprises the steps of:
(a) forming the flange by punching a datum hole in a wafer comprising the polymeric backing film, layer of bioadhesive and removable protective layer;
(b) die cutting the annular bonding element from a web of the multilayer polymeric material;
(c) placing the annular bonding element on to the flange so that the annular bonding element is disposed concentrically with respect to the datum hole;
(d) heat sealing the annular bonding element to the flange;
(e) bringing into contact with the flange a web of a material from which a panel of the outer bag is to be formed and welding the said web to an inner edge of the annular bonding element;
(f) placing the inner bag on the flange and applying pressure to thereto to bond the pressure sensitive adhesive to the second attachment zone;
(g) bringing into contact with the said web a further web of a material from which another panel of the outer bag is to be formed and outline welding the webs together so that they form the outer bag and enclose the inner bag; and thereafter
(i) cutting the webs to release the ostomy bag assembly.
Prior to die cutting the annular bonding element in step (b), one or more tabs (for example, formed form a polyethylene foam material) may be attached to the web of the multilayer polymeric material. The annular bonding element with tab attached may then be cut from the web.
After the heat sealing the annular bonding element to the flange in step (d), the flange is preferably turned over and left to cool with the annular bonding element facing downwards, thereby preventing curling. The cooled annular bonding element and flange assembly may then be placed in a magazine in preparation for the welding step (e).
The process may optionally include a further process step of enlarging the datum hole to accommodate a defined size of stoma in a patient. The outer bag may comprise outer and inner pairs of panels welded together around their peripheries, the inner pair of panels serving to provide a waterproof and odour-proof containment for the inner bag and the outer pair of panels serving as a comfort layer. The comfort layer may typically be formed from a non-woven fibrous material such as a non-woven polyethylene fabric formed from polyethylene fibers.
Further aspects and embodiments of the invention will be apparent from the following brief description of the drawings and the detailed description below.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of an ostomy bag assembly according to one embodiment of the invention. In FIG. 1 , internal features of the assembly are shown by means of dotted lines.
FIG. 2 is a side sectional elevation through the upper part of the ostomy bag assembly of FIG. 1 .
FIG. 3 is an enlarged view of the region A in FIG. 2 .
DETAILED DESCRIPTION OF THE INVENTION
The invention will now be described in more detail, but not limited, by reference to the specific embodiments illustrated in the drawings.
Referring now to the drawings, FIGS. 1 to 3 show an ostomy bag assembly according to a first embodiment of the invention. The ostomy bag assembly of FIGS. 1 to 3 comprises an outer bag 2 and an inner bag 4 attached to an adhesive flange 6 .
The adhesive flange 6 comprises a polymeric backing film 8 which, in this embodiment is formed from polyurethane and has a thickness of approximately 30 μm. Supported on the backing film 8 is a layer 10 , approximately 0.6 millimeters (mm) to 0.9 mm thick, of a hydrocolloid. The hydrocolloid adhesive, which may be of conventional type, serves to secure the ostomy bag to the body of a patient. A siliconized paper release layer 12 covers the hydrocolloid adhesive layer and protects the adhesive layer against damage and/or drying out prior to use of the bag.
On the side of the flange opposite to the hydrocolloid adhesive is an area of the backing film 8 which constitutes a first attachment zone and which is designated in FIG. 1 by the dotted line 14 . An area of the backing film which constitutes a second attachment zone is designated in FIG. 1 by the dotted line 16 .
The flange has means defining an orifice to enable bodily waste to be received by the inner bag. As shown in FIG. 1 , the flange has a central hole 18 , the primary purpose of which is to serve as a datum hole for alignment of the various component parts of the ostomy bag assembly during manufacture. Arranged around the hole 18 is an array of concentric cutting lines 20 which are marked on the surface of the silicone release layer 12 . By way of example, cutting lines are provided for apertures having diameters of 25 mm, 30 mm, 35 mm, 35 mm, 40 mm, 45 mm and 50 mm but cutting lines of different diameters could be used instead. In use, the patient or medical professional will select an aperture size to suit the stoma of a particular patient and will then cut along the appropriate cutting line to form the required aperture.
As an alternative, the datum hole may be widened by an additional cutting step during manufacture to give a range of standard size openings. In many cases, a patient may be able to fit the ostomy bag with a standard sized opening to the stoma without further cutting the adhesive flange. However, in cases where the patient's stoma does not conform to one of the range of standard openings, the patient can select the nearest undersized standard opening and then trim it to fit around his or her stoma.
It will be appreciated from the foregoing that the “means defining an orifice to enable bodily waste to be received by the inner bag” can take the form of an orifice or hole per se or can take the form of markings, score lines, perforations or skip cuts that indicate where a section of the flange may be removed to form or enlarge an opening.
The outer bag 2 is detachably bonded to the first attachment zone 14 on the polymeric backing film 8 of the flange by means of an annular bonding element 22 which is interposed between the first attachment zone 14 and the outer bag.
The annular bonding element is shown in more detail in the enlarged view provided in FIG. 3 . As can be seen from FIG. 3 , the annular bonding element comprises a co-extruded multilayer polymeric material which, in the particular embodiment illustrated, consists of a central layer 24 Surlyn® (partially neutralized ethylene acid copolymer) sandwiched between two layers 26 and 28 of ethylene vinylacetate (EVA). One of the EVA layers has a layer of an EVA copolymer adhesive emulsion 30 coated onto it: the other EVA layer is uncoated. The EVA adhesive-coated co-extruded multilayer polymeric material can be, for example, PerfecSeal coated PerfecFlex® medical forming film (partially neutralized ethylene acid copolymer laminated with EVA) available from Perfecseal Limited of Londonderry, UK.
The outer bag 2 is firmly bonded to the uncoated EVA layer 28 by welding, for example, by radio-frequency (RF) welding. This ensures a secure bond between annular bonding element and outer bag which cannot be disrupted without tearing the fabric of the outer bag.
The EVA adhesive-coated layer 26 , 30 of the annular bonding element 22 is bonded to the first attachment zone 14 by aligning the bonding element 22 in the area of the attachment zone and applying heat with an annular heat sealing tool at a temperature of about 120 degrees C. to about 160 degrees C. for a period of about 2 to about 5 seconds. The EVA adhesive functions as a hot melt adhesive that forms a bond which, whilst easily strong enough to withstand any forces to which it is subjected during use, can be peeled apart using reasonable manual force to separate the outer bag from the adhesive flange. Once peeled away, the outer bag and annular bonding element cannot be reattached to the attachment zone without heat sealing since the EVA adhesive does not have any significant adhesive capability at room temperature and pressure.
In order to assist the annular bonding element 22 to be peeled away from the adhesive flange, a tab 29 is provided. The tab 29 is formed from 0.6 mm thick polyethylene foam coated on one side with a pressure sensitive adhesive to secure it to the annular bonding element 22 .
Disposed within the outer bag 2 , is an inner bag or liner 4 . The inner bag or liner 12 is provided with a ring of pressure sensitive adhesive (not shown), which bonds to polyurethane backing film 8 flange at the second attachment zone 16 .
The outer bag 2 in this embodiment can be formed from materials well known for the construction of ostomy bags. Thus, for example, it can be formed from a tough, flexible, transparent, waterproof material such as polyvinyl dichloride (PVDC), ethylene vinyl acetate (EVA), related materials and combinations thereof in known fashion, one particular material being the EVA/PVDC/EVA film available from Sealed Air of Saddle Brook, N.J., US under the trade name Cryovac MF514, or its equivalent.
In the embodiment shown, the outer bag is formed from a pair of sheets 2 a and 2 b of the flexible waterproof material, one sheet 2 a being cut so as to form an opening, the edge of which is welded to the annular bonding element, and the other sheet 2 b having the same outer periphery, but no opening. The two sheets are secured together around their respective peripheries by welding, (for example, by RF welding) or by means of adhesive. Attached to the sheets 2 a and 2 b by welding around their respective peripheries are panels 32 a , 32 b formed from a fibrous non-woven material, such as, a non-woven polyethylene fabric. The panels 32 a and 32 b serve as a comfort layer, providing a warmer and less harsh feeling against the skin of the patient.
The polymeric materials from which the sheets 2 a and 2 b are formed act as a barrier to gases, and in particular flatus gases. Therefore, in order to prevent ballooning of the ostomy bag through the build up of flatus gases inside the bag, the outer bag is provided with a small opening 36 covered by a flatus filter 34 which is welded to both the sheet 2 b and the panel 32 b.
The inner bag 4 is formed from two pairs of sheets 38 a , 38 b and 40 a , 40 b of polymeric material, welded together along their peripheries. The inner pair of sheets 38 a and 38 b is formed from a mechanically tough warm water soluble grade of polyvinyl alcohol film, for example, a “Solublon EF” (Trade Mark) film available from Aichello, Japan, or its equivalent. The outer pair of sheets 40 a , 40 b is formed from a fibrous non-woven tissue formed from cold water soluble polyvinyl alcohol fibres and rayon fibres, which disintegrates in water.
In use, fecal material from a stomal opening passes through the opening 18 (enlarged where necessary) in the flange and into the interior of the inner bag or liner 4 . When the inner bag or liner 4 is full, the outer bag 2 and the attached annular bonding layer 22 are peeled away from the flange. The flange and inner bag may then be disposed of by flushing down a W.C. (that is, a toilet) and the outer bag disposed of through normal domestic waste channels. A new assembly of inner and outer bag and adhesive flange may then be applied to the patient.
Because the inner bag is formed from materials that are soluble or disintegrable in water, and the hydrocolloid adhesive of the flange is also soluble or erodible in water, the sub-assembly of flange and inner bag rapidly disintegrates during flushing leaving as a residue only the thin polyurethane backing film 8 and rayon fibers from the sheets 40 a and 40 b.
The ostomy bag assembly of the invention can be manufactured by a largely automated production process requiring relatively little manual intervention.
Wafers or blanks which will become the adhesive flange 6 are die cut from sheets of a trilaminar material consisting of the polyurethane backing film 8 , hydrocolloid adhesive 10 and siliconised paper 12 . The wafers can be prepared off site or manufactured in situ. The wafers are loaded into a magazine and are transferred on a rotating carousel to a cutting station where a datum hole 18 is die cut in the centre of the wafer. The hole 18 serves as the datum point for the alignment of the various components of the ostomy bag assembly later in the manufacturing process.
In a separate operation, polyethylene foam tabs are applied to a web of a coextruded multilayer film consisting of Surlyn® (partially neutralized ethylene acid copolymer) sandwiched between two layers of ethylene vinylacetate (EVA), one of which is coated with a layer of an EVA copolymer adhesive emulsion. The tabs are bonded to the web by means of a pressure sensitive adhesive. Rings of the multilayer film with a tab attached are then die cut from the web to form the annular bonding elements 22 .
The annular bonding elements 22 are then automatically conveyed to another work station where they are placed over an adhesive flange wafer so that the annular bonding element is concentric with the datum hole 18 in the wafer. Heat and pressure are then applied to the annular bonding element to form a heat seal between the annular bonding element and the polyurethane backing film of the bonding element.
Once the heat seal has been created, the sub-assembly of adhesive flange and annular bonding element is removed, turned over and placed on a tray to cool with the annular bonding element facing down so as to prevent curling.
After cooling, the adhesive flange-annular bonding element sub-assemblies are loaded into a magazine with the annular bonding element facing up and transferred to a separate machine for creating the ostomy bags.
In a first step in the creation of the ostomy bags, a first web of a non-woven fabric (from which comfort panel 32 a is made) is die cut to form a series of circular holes. A second web, which is formed from an EVA/PVDC/EVA film (which will become panel 2 a ) is then die cut with a series of holes of a smaller diameter than the holes in the first web. The first and second webs are then secured together by means of peripheral tack welds.
Adhesive flange-annular bonding element sub-assemblies are then transferred from their magazine to a welding station where they are successively welded to the second web so that each sub-assembly surrounds one of the holes in the web.
The first and second webs carrying the adhesive flange-annular bonding element sub assemblies pass through a further processing station where pre-formed inner bags, each having an opening surrounded by a ring of pressure sensitive adhesive, are affixed to the annular bonding elements.
At a separate filter welding station, a third web of material, from which the panel 2 b will be formed, and a fourth web of material, from which the panel 32 b will be formed, are brought together and a filter 34 is welded to the surface of the third web. The welding operation is carried out for a period of time sufficient to ensure that the fourth web is also welded to the third web in the region of the filter. The region over the filter where the third and fourth webs are welded together is then perforated to form an exit hole for flatus gases passing through the filter.
Once the filter has been affixed, the first, second, third and fourth webs are passed through another welding station where the four webs are outline welded together (the outline of the weld defining the shape of the ostomy bag). The webs are then cut around the outer edge of the outline to release the completed ostomy bag assembly from the webs. The completed ostomy bag assemblies may then be inspected and packed.
During the assembly of the ostomy bag, a further and optional cutting step may be employed in which the datum hole is enlarged to a size suitable for fitting about a stomal opening. During this step, differently sized cutters may be used for different batches thereby enabling the creation of a range of ostomy bags with different sizes of opening.
EQUIVALENTS
It will readily be apparent that numerous modifications and alterations may be made to the specific embodiments of the invention described above without departing from the principles underlying the invention. All such modifications and alterations are intended to be embraced by this application. | The invention provides an ostomy bag assembly including an outer bag and an inner bag secured to one side of a flange. The inner bag is removable to facilitate disposal. The flange has a polymeric backing film and a layer of bioadhesive for securing the ostomy bag assembly to the body of a patient. The flange includes an orifice to enable bodily waste to be received by the inner bag. The outer bag is detachably bonded to a first attachment zone on the flange and the inner bag is secured to a second attachment zone on the flange. The outer bag is mounted to the flange by an annular bonding element is formed from a multilayer polymeric material comprising first and second ethylene vinyl acetate layers and a polymeric support layer interposed there between. A method of fabricating ostomy bags is also provided. | 8 |
FIELD
This invention concerns a method of internally lubricating a positive displacement machine when operating as an expander of a compressed gas.
Such a machine which may be in the form of a scroll expander, a screw type expander or one using movable vanes, requires a degree of lubrication of the working surfaces of the expander thus to avoid wear of such surfaces which in time would prevent the expander from operating in a positive manner.
BACKGROUND
Typically in such a machine where the gas flow into the expander may be in excess of 200 liters per minute, a lubricant must be supplied and injected into the expansion chamber of the machine, at a rate of around 10 milliliters per minute. In addition to the cost of using mineral oil lubricants at such a flow rate and accommodating a reservoir of sufficient size, there are additionally difficulties in subsequently separating the lubricant from the gas exhausted from the expander, since the lubricant will typically be entrained as a mist or fume.
SUMMARY
It is an object of the present invention to provide a method of lubricating a positive displacement expander, and to provide a system incorporating the expander, a supply of compressed gas and a reservoir of lubricant, wherein the aforementioned concerns are substantially alleviated.
According to the present invention there is provided a method of lubricating a positive displacement machine operating as an expander of a compressed gas, comprising the steps of introducing into an expansion chamber of the machine a lubricant whose pour point temperature is greater than the reduced operating temperature of the machine in said expansion chamber as determined by the expanding gas, thus causing the lubricant to freeze-adhere to the internal surfaces of the expansion chamber.
The lubricant may be introduced into the expansion chamber simultaneously with the compressed gas to be expanded.
The lubricant may be contained with the compressed gas in a storage vessel prior to its supply to the positive displacement machine, or alternatively the lubricant may be introduced into the expansion chamber from a reservoir separate from a storage vessel containing the compressed gas.
The pour point temperature of the lubricant may exceed the operating temperature of the machine in the expansion chamber by at least 50° C.
The temperature differential determined by the pour point of the lubricant and the operating temperature of the machine in the expansion chamber may be such that the freeze-adhered lubricant becomes fluid under increased pressure at a point of contact of the working surfaces of the expander, then refreezes when the surfaces separate.
The volume of lubricant introduced into the machine, per unit time, may be in the region of 0.0005% of the volume of compressed gas passing through the machine for the same unit time.
The temperature of the lubricant prior to introduction into the expansion chamber may be controlled such that it remains fluid until frozen in the expansion chamber by the expanding gas.
Further according to the present invention there is provided a system comprising a positive displacement expander; a supply of compressed gas connected to the expander; and means connected to the expander to supply thereto a lubricant having an inherent pour point temperature greater than the operating temperature of the gas when expanding within the expansion chamber of the expander.
The system may include means to control the temperature of the lubricant supplied to the expansion chamber.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 depicts schematically one embodiment of a system comprising a positive displacement expander disclosed herein.
FIG. 2 depicts schematically one embodiment of a system comprising a positive displacement expander disclosed herein.
FIG. 3 depicts schematically one embodiment of a system comprising a positive displacement expander disclosed herein.
DETAILED DESCRIPTION
The invention is principally, though not exclusively, intended for use with a system for producing an uninterrupted supply of electrical power by providing a supply of compressed gas, usually air, and passing the gas through a positive displacement expander such as a scroll compressor operating in reverse to expand the gas, the rotor of the expander being connected to an electrical generator to produce electrical power in the event of failure of the mains electrical supply.
A scroll expander operating this way requires lubrication to prevent wear of the contacting surfaces of the machine, while providing a seal between the expanding pockets of gas.
Low pour point mineral oils will, in conventional methods, require a supply of a lubricant somewhere in the region of 10 milliliters per minute for a gas flow into the system in excess of 200 liters per minute for an output power typically in the region of 20 KW, and an inlet pressure of 40-50 bar, for example. The oil then becomes entrained within the expanding gas which, in an open loop system, cannot be permitted, on exhaust, to escape into the atmosphere without dis-entraining the oil mist or fume from the gas. Additionally, utilisation of lubricant at this kind of level, in order to be economically acceptable, requires that the oil be recovered for re-use.
The present invention is based upon the concept that a lubricant oil which will freeze-adhere to the internal surfaces of the machine during its operation will require a much lower quantity of lubricant which in turn reduces the amount of lubricant required to be collected on exhaust from the machine. This, in turn, enables the design of such a system to be improved insofar as a storage reservoir for the oil may be considerably smaller. For this purpose, a mineral oil, for example BP RCR 32, having a pour point of approximately −20° C. may be selected as the lubricant for use in a scroll expander whose operating temperature is typically in the region of −85° C. so that the pour point of the lubricant is at least 50° C. and in this example some 65° C. greater than the operating temperature of the machine.
As the oil enters the expansion chamber it immediately becomes frozen and adheres to the internal working surfaces of the scroll and the body of the machine until, momentarily, it experiences the intense pressure created by the working surfaces coming into contact whereupon the lubricant melts and becomes fluid at that point thus to provide the protecting and sealing properties of the lubricant. Then, as the working surfaces separate, the lubricant refreezes on the cold expander surfaces thus preventing the lubricant from being displaced with the expanding gas.
Experimentation revealed that if the compressed gas entering the machine is preheated, such that its temperature did not fall below the pour point of the lubricant, a minimum supply rate for the lubricant was 10 milliliters per minute when introduced with the heated gas. When the experiment was repeated with unheated gas a rate of lubricant supply as little as 1 milliliter per minute was found sufficient since the working temperature was then below the pour point of the lubricant. In the repeat experiment the scroll expander was operated for approximately 30 minutes with a lubricant feed rate of 1 milliliter per minute, whereupon the machine was opened up for inspection and the oil was found to have been evenly distributed across the scroll labyrinth faces as a frozen film.
In a further experiment a lubricant having a pour point lower than the normal working temperature of the expander was used and the lubricant remained in a fluid state within the machine. Under those conditions a lubricant feed rate of 10 milliliters per minute was required in order to protect the scroll labyrinth faces from wear and so it was clear that the freeze-adhering of lubricant on to the scroll faces has significant advantage since it increases lubricant retention in the system and considerably reduces the quantity of lubricant required.
Operating parameters using a high pour point lubricant were found to be that 1 milliliter of the mineral oil lubricant per minute was adequate with a gas flow into the system of 210 liters per minute of gas at 40 bar pressure. By volume, this equates to 0.0005% of lubricant to gas. The volume of lubricant required may be determined according to the output power, or the rotational speed, or a combination of both parameters.
By significantly reducing the amount of lubricant required in a machine of this kind there is a considerable cost saving in the manufacture of such a system since the lubricant reservoir can be kept as compact as possible, and it is conceivable also that the product could be sealed for life with a 2-liter oil reservoir being sufficient to provide the system with lubricant for its expected lifetime which therefore would never require replenishment.
The concept is of considerable value on the exhaust side of the system since the oil is frozen on exit from the scroll and makes it much easier to dis-entrain from the exhausted gas than if the oil were in a mist or a fume. The reduced amount of lubrication also means that the amount of oil needed to be collected on exit from the scroll is considerably reduced which is of particular value in an open loop system where re-circulating the lubricant would be difficult or costly to achieve and so keeping the lubricant required to a minimum alleviates the need for excessive filtering of the exhaust gas and allows for longer periods between system maintenance.
Where a positive displacement expander is to be used in environments where the ambient temperature falls below the pour point of the lubricant it may be necessary slightly to heat the lubricant prior to introduction into the chamber in order to keep it liquid such that it easily flows through the system prior to introduction. Additionally, there may be some advantage in monitoring and controlling the temperature of the lubricant so that when it becomes entrained in the gas stream it is at an ideal temperature so that it freeze-adheres instantly on contact with the working surfaces.
As an alternative to reservoir storage, the lubricant may be contained within the compressed gas in a storage vessel prior to supply to the positive displacement machine such that the moist gas serves as the lubricant within the machine and/or mixes with another lubricant such as a mineral oil to create an emulsion which freeze-adheres to the working surfaces within the machine. In some cases, if air is the stored compressed gas, moisture (water) naturally present in the compressed air may alone serve as the lubricant or may combine with another lubricant to form an emulsion. Alternatively, the lubricant may be another aqueous-based liquid alone or mixed with an oil-based liquid, all provided that it's freezing (pour point) temperature is above the operating temperature of the machine in the expansion chamber.
One embodiment of a system disclosed herein is depicted schematically in FIG. 1 . FIG. 1 shows a system comprising a positive displacement expander 100 having an expansion chamber 110 ; a supply of compressed gas 112 connected to the expander 100 ; and means 114 connected to the expander 100 to supply thereto a lubricant having an inherent pour point temperature greater than the operating temperature of the gas when expanding within the expansion chamber 110 of the expander 100 , and wherein the temperature differential determined by the pour point of the lubricant and the operating temperature in the expansion chamber 110 is such that the lubricant becomes fluid under increased pressure at a point of contact of the working surfaces 124 of the expander 100 , then freezes when the surfaces 124 separate. The system can include means 116 to control the temperature of the lubricant supplied to the expansion chamber 110 .
Another embodiment of a system disclosed herein is depicted schematically in FIG. 2 . FIG. 2 depicts a system comprising a positive displacement expander 100 having an expansion chamber 110 ; a supply of compressed gas 112 connected to the expander 100 ; and a supply of lubricant 118 connected to the expander 100 , wherein the supply of lubricant 118 provides to the expander 100 a lubricant having an inherent pour point temperature greater than the operating temperature of the gas when expanding within the expansion chamber 110 of the expander 100 , and wherein the temperature differential determined by the pour point of the lubricant and the operating temperature in the expansion chamber 110 is such that the lubricant becomes fluid under increased pressure at a point of contact of the working surfaces 124 of the expander, then freezes when the surfaces 124 separate. The system can include a temperature controller 120 that controls the temperature of the lubricant supplied to the expansion chamber 110 .
As shown schematically in FIG. 3 , the system can comprise a positive displacement expander 100 having an expansion chamber 110 ; a supply of compressed gas 122 connected to the expander 100 ; wherein the lubricant is contained with the compressed gas in a storage vessel 122 prior to supply to the positive displacement expander 100 . The compressed gas and lubricant can be supplied via means 126 to the expander 100 , wherein the lubricant can have an inherent pour point temperature greater than the operating temperature of the gas when expanding within the expansion chamber 110 of the expander 100 , and wherein the temperature differential determined by the pour point of the lubricant and the operating temperature in the expansion chamber 110 is such that the lubricant becomes fluid under increased pressure at a point of contact of the working surfaces 124 of the expander, then freezes when the surfaces 124 separate. | A method and system for lubricating a positive displacement machine operating as an expander of a compressed gas, comprising introducing into an expansion chamber of the machine a lubricant whose pour point temperature is greater than the operating temperature of the machine in the expansion chamber as determined by the expanding gas, which thus causes the lubricant to freeze-adhere to the internal surfaces of the expansion chamber, to become fluid under increased pressure at a point of contact of the working surfaces of the expander and then to refreeze when the surfaces separate. Considerable reduction in the quantity of lubricant is realized with the attendant advantage that dis-entrainment of lubricant from the gas exhausted from the machine is largely avoided. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to vertical direct fired strip heating furnaces in continuous annealing furnaces for heating steel strips.
Although it is a well known fact that a flame cleaning process is frequently used in a continuous zinc plating process, in this process, in the initial stage of the heating of the steel strip, in order to decompose and clean the rolling oil adhered to the surface of the steel strip, means for heating the steel strip in a slight oxidation atmosphere is employed, and in general, a furnace having a direct fired combustion heating system for partly burning the fuel is used.
The conventional vertical direct fired strip heating furnace of this kind has been constructed with one heating chamber, and this limits the processing capacity. The realization of a vertical direct fired strip heating furnace constructed with more than two heating chambers has been strongly demanded. Also, recent technical needs for energy savings have resulted in a strong demand for the realization of a vertical direct fired strip heating furnace provided with a plurality of passages which consists of more than two chambers.
In the conventional direct fired strip heating furnace, since it is of the one heating chamber construction, when the processing capacity is increased, due to a limit of the furnace height because of economic reasons, there is a limit in the heating temperature, and the extra load tends to be applied to the succeeding indirect heating reduction chamber. In case the processing capacity is increased too much, the temperature is limited to an extent which prevents the realization of the original process of flame cleaning. This is a big drawback of the conventional furnace. Also, when heating is done in one chamber, the combustion gases are exhausted at the furnace top portion, thus making the thorough utilization of exhaust gases difficult, and a gas sealing device provided at the opening portion for introducing the steel strip to the heating chamber must be constructed to widthstand the high temperature gases.
The technical concept of preheating the steel strip with combustion exhaust gases of the vertical direct fired strip heating furnace (as disclosed in U.S. Pat. No. 3,532,329) is known, but this technique is such that the preheating chamber and heating chamber for treating the steel strip by exhaust gases of the direct fired strip heating chamber are not communicated, namely, the steel strip passing the preheating chamber is exposed once to the atmosphere, and thereafter is introduced to the heating chamber. In this case, in order not to cause excessive oxidation of the surface of the steel strip exposed to the atmosphere, there are problems such as that the preheating temperature of the steel strip must be limited to a low temperature, and also that the gas sealing device at the opening portion for introducing the steel strip to the heating chamber is required to have a construction capable of withstanding the high temperature, similar to the situation in the conventional vertical direct fired strip heating chamber consisting of one chamber.
In the present invention, in order to solve the foregoing problems, more than two heating chambers are provided in communication. Heating chamber as mentioned herein means a direct fired heating chamber or a preheating chamber. With the foregoing arrangement, a sufficient heating temperature is secured to meet with the necessary processing capacity, and moreover the excessive oxidation of the surface of the preheated steel strip is prevented, the exhaust gas temperature from the preheating chamber is lowered to accomplish an energy saving, the thermal requirements for the gas sealing device at the opening portion for introducing the steel strip is relieved, and, an important thing to be noted here, the furnace is provided with a protection countermeasure for the rolls.
In general, the direct fired strip heating furnace whose primary purpose is to clean the surface of the steel strip by flame performs the flame cleaning process effectively, and also for the purpose of improving the heating efficiency, it is operated at high a temperature ranging from 1000° C.-1250° C. Accordingly, in order to use metal inside furnace rolls economically at such high temperatures, it is necessary to hold the temperature of the inside furnace roll chamber below at least 1000° C. Moreover, in the low temperature region where the temperature of the steel strip is not sufficiently high, then in order to prevent damage to the rolls due to thermal stress generated on the body of the rolls, adjustment of the temperature in the inside furnace roll chamber to a proper range is required.
When there is a big difference between the atmospheric temperature in the circumference of the rolls and the temperature of the passing steel strip, a big thermal stress occurs in the axial direction of the body of the rolls, and in the worst case, cracks may be caused to occur in the body of the rolls. Namely, the center portion of the body of the rolls contacting the low temperature steel strip is constantly cooled by the steel strip and as a result, there occurs an immensely large temperature difference between such center portion and the shoulder portion not contacting the cooled steel strip. According to actual measurement by the inventors, in case the temperature difference is large and may reach 350° C. to 400° C., and thermal stress sufficient to break down the body of the rolls a short time is generated. Normally, in order to hold the thermal stress generated on the body of the rolls to a degree that produces no actual damage from a practical standpoint, it is necessary to hold the atmospheric temperature in the roll chamber above the temperature of the passing steel strip or within temperatures of the steel strip temperature plus 500° C. In this regard, the reason for making the atmospheric temperature above the temperature of the passing steel strip is not to cool the steel strip in the roll chamber. To protect the rolls, water cooling jackets may be disposed in the circumference of the inside furnace rolls to cool the surfaces of the rolls, or the rolls may be cooled indirectly by disposing an air cooling pipe. However, these methods are accompanied by various problems such as danger of water leakage, dew condensation, only a slight cooling of the atmospheric gases in the circumference of the inside furnace rolls, as well as the fact that the inner surface of the body of the rolls is heated by the radiating gases of high temperature filled in the inner surface of the inside furnace rolls, and in addition to thermal stress in the axial direction, a temperature difference is generated between the inner and outer surfaces of the cylinder of body of the rolls to increase the thermal stress in the radial direction.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a vertical direct fired strip heating furnace which is capable of large capacity processing and of saving energy.
Another object of the present invention is to provide a vertical direct fired strip heating furnace that protects the rolls provided in the furnace from high temperature combustion gases and that is capable of preventing damage to the rolls.
A further object of the present invention is to provide a vertical direct fired strip heating furnace of large capacity and requiring less installation space.
In order to accomplish the foregoing objects, the present invention is characterized in that a furnace proper is formed by more than two heating chambers which are disposed in parallel and which are communicated with each other. A separation chamber for accommodating the inside furnace rolls at adjacent pairs of parallelled chambers is provided in at least one location (in general, at one location less than the number of the parallell chambers). The inside furnace rolls are separated from the main flow of the combustion gases, and the inside furnace rolls are protected by adjusting the atmospheric gas temperature of the roll chambers to within a fixed range.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional elevation of one example of a vertical direct fired strip heating furnace according to the present invention.
FIG. 2 is a cross-section showing one example of a shielding device for separating the roll chamber from the direct fired strip heating chamber.
FIG. 3 is a schematic view of another example of the device for adjusting the temperature in the roll chamber.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The vertical direct fired strip heating furnace according to an embodiment of the present invention is constructed in such a way that there are provided two vertical direct fired strip heating chambers provided with top and bottom inside furnace rolls and a preheating chamber communicated with one of the heating furnace chambers to preheat the steel strip with the high temperature combustion product from the direct fired strip heating chamber. The top and bottom inside furnace rolls are separated from the main flow of the combustion gases, and the atmospheric temperature of the roll chambers housing the inside furnace rolls are controlled to a temperature above the temperature of the steel strip passing the roll chamber and also to a temperature below the combustion gas temperature (in the practice, below 1000° C.). A device for protecting the inside furnace rolls from the high temperature hot gasses is further provided, whereby the present invention is not limited to two direct fired strip heating chambers and one preheating chamber, and it is possible to provide one or more than three direct fired heating chambers depending on the required processing capacity. Also, it is possible to provide a plurality of preheating chambers to accomplish energy savings.
Embodiments of the present invention will be described in detail in the following by referring to the drawings.
In FIG. 1, there is shown preheating chamber (11) which is vertically and parallelly arranged in the order from the upstream side of the flow of strip S with two direct fired strip heating chambers (21), (25). The steel strip S passes a deflector roll (1) and passes sequentially through preheating chamber (11), direct fired strip heating chambers (21), (25), and also through a throat (5) and then moves through a heating reduction chamber (not shown). The combustion gases are made to flow in the directions A, B, C, opposite to the advancement of the strip S, by a blower (not shown) provided in the heating chamber disposed behind the direct fired strip heating chamber.
The preheating chamber (11) is provided at the inlet (12) thereof with a sealing device (14) consisting of two pieces of seal rolls capable of shifting with respect to the surface of the strip, and the sealing device prevents the emission of the combustion gases outside the furnace through the inlet (12). At a location immediately below the inlet (12), a combustion gas discharge port (15) is provided, and the combustion gases are discharged outside the building through a furnace pressure adjusting device and exhaust stack (not shown).
First direct fired strip heating chamber (21) and second direct fired strip heating chamber (25) succeeding the preheating chamber (11) are provided with a large number of burners (29) that open to the respective chambers, and the strip S is directly heated by the burners (29).
An inlet (22) of the first direct fired strip heating chamber (21) and an outlet (13) of the preheating chamber (11) are connected by a horizontally extending flue (31), and an outlet (23) of the first direct fired strip heating chamber (21) and an inlet (26) of the second direct fired strip heating chamber (25) are similarly connected by a flue (33). In these flues (31) and (33), only the combustion gases pass, and the strip S does not pass therethrough.
At the bottom side of the flue (31), a bottom roll chamber (41) is provided in parallel with the flue (31), and the bottom roll chamber (41) is separated from the preheating chamber (11), from the first direct fired strip heating chamber (21), and from flue (31) by a partition (42). The partition (42) is provided with a narrow passage (43) for passing the strip S and which opens to the outlet (13) of the preheating chamber (11) and a similar passage (44) that opens to the first direct fired strip heating chamber (21). Water cooling dampers (45) and (46) are provided on the passages (43) and (44) and are rotatable around horizontal axes to adjust the openings of the passages. The water cooling dampers (45) and (46) are opened and closed by manipulation from outside the furnace.
Below the passages (43) and (44) are provided a pair of guide rolls (47), each for changing the advancing direction of the strip S by 90°, and this pair of guide rolls (47) can be rotatably driven by a drive device (not shown).
At the top side of the flue (33), a top roll chamber (51) similar to the bottom roll chamber (41) is provided, and the top roll chamber (51) is separated from the first direct fired strip heating chamber (21), from the second direct fired strip heating chamber (25) and from flue (33) by a partition (52). The partition (52) is provided with passages (53) and (54), and a pair of guide rolls (57) are housed in the top roll chamber (51).
In order to separate the top roll chamber (51) more positively, as shown in FIG. 2, it is preferable to provide a throat portion (62) and a shielding device (61) including a water cooling damper (64) provided in a space (63) formed between the throats. The throat portion (62) preferably provides as small a gap as possible to the surface of the strip S, but when workability at the threading operation of the strip is taken into consideration, it is desirable to maintain about 100 mm at one side. Accordingly, in order to minimize the radiation heat entering the roll chamber (51) from the high temperature heating chambers (21) and (25) and to minimize the inflow of the combustion gases, it becomes effective to provide the openable water cooling damper (64). Also, instead of the water cooling damper (64), it is effective to employ a system wherein an openable gas blowing nozzle is provided to produce a gas curtain effect.
The gap from the surface of the strip when the water cooling damper (64) or the gas blowing nozzle is closed is preferably maintained at about 25 mm for one side when presence of the wave of the strip is taken into consideration. Accordingly, at the time of threading of the strip, the water cooling damper or the gas blowing nozzle must be opened to facilitate an easy threading operation. Although it is preferable to provide a similar throat portion between the bottom roll chamber (41), heating chamber (21) and preheating chamber (11), in the present invention the throat portion is not provided, to thus facilitate the operation of drawing out the strip outside the furnace at the time of breaking of the strip. The openable water cooling dampers (45) and (46) are provided to limit to a minimum the amounts of the radiation heat and of the combustion gases entering and flowing into chamber (41). The water cooling dampers (45) and (46) installed in the bottom roll chamber (41) are basically the same as top damper (64), but consideration of enlarging the opening is required as compared with the time when the furnace is opened to remove the strip.
The bottom partition (42) prevents the high temperature gas from entering the bottom roll chamber (41), and the gas temperature in chamber (41) is maintained at a slightly higher desired temperature to minimize the thermal stress generated in the body of the rolls by connecting chamber (41) with a heating and reducing chamber and the throat (5) by a duct (71). The duct (71) is provided with a heat exchanger (72) for cooling the combustion gases to a proper temperature, a blower (73) for blowing the combustion gases into the bottom roll chamber (41), and an adjusting valve (74) for adjusting the combustion gas flowrate. The flowrate adjusting valve (74) is controlled by a temperature detecting controlling device (75) which detects the temperature in the bottom roll chamber (41) and controls valve (74).
Similarly, the top roll chamber (51) is connected with the preheating chamber (11) by a duct (81) having therein a heat exchanger (82), blower (83) and flowrate adjusting valve (84). The flowrate adjusting valve (84) is controlled by a temperature detecting controlling device (85) provided in the top roll chamber (51).
The high temperature gases to be supplied to the bottom roll chamber (41) or the top roll chamber (51) are extracted from the respective proper positions in the furnace, and this feature is not limited to the illustrated embodiment, but rather gases supplied from outside the furnace may also be used. FIG. 3 shows this kind of arrangement, and a vessel (92) filled with the properly heated and pressurized gases and the bottom roll chamber (41) are connected by a duct (91) having therein a flowrate adjusting valve (93), and the flowrate adjusting valve (93) is controlled by a temperature detecting controlling device (94). The bottom roll chamber (41) is maintained at a proper temperature by the high temperature gases from the vessel (92).
In the example shown in the drawings, two heating chambers (21) and (25) and one preheating chamber (11) are provided, and throat portions for the protection of the rolls are installed only for the top roll chamber (51), but the present invention is not limited to this specific example, and it is needless to say that more than two heating chambers, and more than two preheating chambers as well as a throat portion (62) for each roll chamber may be provided.
Although the present invention has been described in the foregoing, the operation of the apparatus will now be explained in the following. The strip S enters a preheating chamber (11) from an inlet seal device (14) by means of a deflector roll (1), and is preheated to about 200° C. by combustion gas of about 1000° C. flowing from the heating chamber (21), and then is heated to about 450° C. by the high temperature gases of 1000° C. to 1150° C. in the first direct fired strip heating chamber (21) ranging from the bottom roll (47) in the bottom roll chamber (41) to the top roll (57) in the top roll chamber (51), and then again is heated to about 650° C. by the high temperature gases of 1150° C. to 1200° C. in the second vertical direct fired heating chamber (25) ranging from the top roll (57) to the bottom roll (47), and then is fed to a successive indirect heating and reducing chamber.
The major portion of the combustion gases generated in the vertical direct fired strip heating chambers, as shown by Arrows A, B, C, does not enter the separate top and bottom roll chambers, but is discharged outside the furnace through the discharge port (15) after passing through flues (31) and (33).
Particularly, as shown in FIG. 2, if a protecting device is provided in a communicating portion of the heating chamber and roll chamber, it is possible to shield the radiation heat almost completely, and if necessary, the temperature in the roll chambers can be adjusted by the heat exchangers (72, 82) and blowers (73, 83), and abnormal temperature increases in the roll chambers can be prevented.
Remarkable effects to be obtained by the present invention are enumerated in the following.
(1) In the conventional vertical continuous zinc plating installation, the processing capacity is limited to about 30 tons per hour in a single chamber vertical direct fired strip heating furnace due to a limit of furnace height on grounds of construction cost and operating technique. However, according to the foregoing embodiment of the present invention, it is possible to construct a large size installation which has processing capacity of 140 tons per hour while maintaining an economical flame cleaning process. An even larger capacity installation can be constructed by connecting the direct fired heating chambers.
(2) It becomes possible to connect the preheating chamber to the entry side of the heating chamber, and the strip is not exposed to the atmosphere through the connection with the preheating chamber, thus making possible the preheating of the strip to high temperatures.
As a result, in the prior art, in comparison with the case where there is no preheating chamber, a reduction of fuel consumption of only about 15-20% is achieved, but by the method of the present invention, with the heating chamber connected to a preheating chamber of the same height as the heating chamber, fuel savings 40% or more can be accomplished.
(3) In the large capacity processing furnace, the space for the installation becomes smaller.
Namely, in indirect strip heating, due to a limit of heat resisting material, a maximum surface temperature is about 950° C., and in case of the direct fired strip heating, gas temperature (furnace temperature) is set at 1200° C., and also the coefficient of heat-transfer related to radiation heat-transfer is φ CH =0.25 in case of the indirect heating, and in case of the direct fired strip heating, φ CG =0.4-0.45, whereby the ratio of effective heating length is: ##EQU1## and as a result, it becomes about one fifth.
As a more concrete example of the above, assume the example of a continuous annealing furnace for zinc plating having a maximum processing capacity of 140 ton/hour as mentioned in the foregoing, and in case the flame cleaning process is employed and the vertical direct fired strip heating furnace according to the illustrated embodiment of the present invention is employed, assume that the steel strip is heated up to 650° C. in the direct fired strip heating furnace, and then in the succeeding indirect heating and reducing zone, it is heated up to 750° C., a total number of strip strands becomes nine strands, but in case an electric cleaning process is employed and all the operations are accomplished by the indirect heating method, it becomes sixteen strands.
Also, the length of the entire heating zone can be shortened by 20%.
(4) In a large capacity processing furnace, the mill oil on the surface of the strip can be subjected to flame cleaning, and the electric cleaning installation can be eliminated.
(5) With the addition of the effective inside furnace roll protecting device, it becomes possible to use plain ordinary heat resisting alloy rolls.
It is to be understood that the apparatus according to the present invention can be applied to continuous annealing furnaces for all kinds of steel sheets. | A vertical strip heating furnace includes at least two vertical direct fired heating chambers which are arranged in parallel which are communicated with each other. A separation chamber for housing inside furnace rolls at adjacent pairs of the chambers is provided in at least one location. The inside furnace rolls are separated from the main flow of the combustion gases and the temperature of the atmosphere in the chambers housing the inside furnace rolls is adjusted to within a fixed range. This strip heating furnace is capable of large capacity processing and is designed to save energy, and the inside furnace rolls are free from breakage due to thermal stress. | 2 |
This is a continuation of application Ser. No. 405,021 filed Oct. 10, 1973, now abandoned, which in turn is a continuation of application Ser. No. 235,617 filed Mar. 17, 1972, now abandoned, which in turn is a continuation of application Ser. No. 869,135 filed Oct. 24, 1969, now abandoned.
BACKGROUND OF THE INVENTION
For many years attempts have been made to use shotgun shells in guns designed for shooting bullets. Unfortunately, the barrels of such firearms are rifled and, as the shell passes down the barrel, the rifling causes the individual pellets to move in a helical path. When the pellets leave the muzzle of the gun, centrifugal action causes the pellets to move outwardly from the barrel axis. At any appreciable distance from the gun, the pellets have moved outwardly so far from the axis that the group is useless either for target shooting or for shooting small game. These and other difficulties experienced with the prior art devices have been obviated in a novel manner by the present invention.
It is, therefore, an outstanding object of the invention to provide a gun that may be used effectively with both bullets and shotgun shells.
Another object of this invention is the provision of a firearm having a rifled barrel that may be used for shooting shotgun shells without the pellets moving laterally of the barrel axis as they leave the gun.
A further object of the present invention is the provision of a rifled gun that gives a close pellet pattern when used with shotgun shells.
It is another object of the instant invention to provide a rifled handgun which can be used with birdshot and give a pattern small enough to knock down small game despite the small weight of pellet necessitated by even the largest caliber of bullet.
A still further object of the invention is the provision of a handgun which makes an excellent survival gun because of its ability to shoot both bullets and shotgun shells with accuracy.
With these and other objects in view, as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.
SUMMARY OF THE INVENTION
In general, the invention has to do with a gun for use alternately with a shotgun shell and a bullet. It has a barrel with spiraled rifling and a tubular element attachable to the muzzle of the barrel. The inner surface of the element is formed with longitudinally-extending vanes to remove spiral motion from the shot to prevent it from spreading as it leaves the gun.
More specifically, a second tubular element provided with gas vents is interposed between the muzzle of the barrel and the first tubular element. The second tubular element is provided with internal threads, and the first tubular element is provided at one end with cooperating external threads, the first tubular element being provided with flat wrench-engaging surfaces. The vanes are located away from the threaded end and are tapered from that end to their portions of greatest radially inwardly-extending position at the other end.
BRIEF DESCRIPTION OF THE DRAWINGS
The character of the invention, however, may be best understood by reference to one of its structural forms, as illustrated by the accompanying drawings, in which:
FIG. 1 is a perspective view of a gun embodying the principles of the present invention,
FIG. 2 is a perspective view of a portion of the gun,
FIG. 3 is an end elevational view of a portion of the gun,
FIG. 4 is a sectional view taken on the line IV--IV of FIG. 3,
FIG. 5 is an end elevational view of another portion of the gun, and
FIG. 6 is a sectional view taken on the line VI--VI of FIG. 5.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, wherein are first shown the general features of the invention, the gun, indicated generally by the reference numeral 10, is shown as having a rifled barrel 11 associated with a frame 12, a grip 13. The gun is of the type shown and described in U.S. Pat. No. 3,561,149. To the muzzle are fastened a first tubular element 14 and a second tubular element 15. The first tubular element 14 is provided with axially-extending vanes 16 (see FIGS. 5 and 6).
In FIG. 2 it can be seen that the first tubular element 14 is attached to one end of the second tubular element 15, the other end of which is connected to the muzzle of the barrel 11. Extending over the barrel and the second tubular element is a front sight.
FIGS. 3 and 4 show the manner in which the second tubular element 15 is constructed. Through the element extends a bore 18 which is provided with a cylindrical counterbore 19 which fits tightly over the end of the barrel 11. From the main bore extend gas vents 21 located in the upper quadrants only. At the end opposite the counterbore the bore 18 is provided with internal threads 22.
The details of the first tubular element 14 are shown in FIGS. 5 and 6. At one end it is provided with external threads 23 which engage cooperatively with the internal threads 22 of the second tubular element. At that end of the element, it is provided with a cylindrical portion 24 which is the same size as the corresponding outer surface of the other element. The portion 24 merges through a transition portion 25 to a smaller cylindrical portion 26.
Through the element runs a bore 27 which is exactly the same diameter as the bore 18. At the threaded end of the bore is a portion 28 which is free of the vanes 16. At the other end of the bore is a portion 29 throughout which the vanes 16 have their greatest radial inward extent. Between the two portions lies a portion 31 in which the vanes are tapered. The surface 24 is provided with flat wrench-engaging surfaces 32.
The operation of the apparatus will now be readily understood in view of the above description. In a practical embodiment of the invention, the barrel is designed for use with 45 caliber bullets. When used with such bullets, the first tubular element 14 is removed. When fired, the bullet passes down the barrel and is caused to spin by the rifling. The bullet is maintained on the axis of the barrel as it leaves the gun because of this spin by gyroscopic principle.
When the gun is used with a shotgun shell, the 0.45 chamber is capable of receiving a 0.410 shell. The first tubular element is fastened in place by the interengagement of the external threads 23 with the internal threads 22. The firing of the gun projects the pellets down the barrel and the rifling causes the body of pellets to rotate about the axis of the barrel. As the pellets pass through the bore 27 of the tubular element 14 the straight vanes 16 remove their helical motion, so that they leave the gun moving in straight lines parallel to the barrel axis. There is, therefore, no action of centrifugal force and no tendency of the pellets to spread.
It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed. | This invention has to do with a gun and, more particularly, to a firearm having a rifled barrel which can be used effectively with shotgun shells. | 5 |
RELATED APPLICATION
[0001] This is a continuation-in-part of patent application Ser. No. 10/106,227, filed Oct. 31, 2001.
FIELD OF THE INVENTION
[0002] The present invention relates to an apparatus for visually indicating the open and closed position of a valve having a linear moving valve stem.
BACKGROUND OF THE INVENTION
[0003] It is often difficult to determine at a glance whether a valve is open or closed. This problem is of particular concern in consumer goods, such as with valves on propane gas tanks, where harmful gases could escape without notice and potentially cause serious injury. Known types of indicating devises are generally not well suited for use in valve-containing consumer goods because these indicators are typically integrated with the valve assembly and/or contain a number of moving parts which increase the possibility of malfunction and also increase the cost of production.
[0004] Known inventions include those in which the valve indicator is part of the valve handle assembly. For example, U.S. Pat. No. 3,910,308 describes a valve indicator consisting of a knurled valve handle having windows that expose an on/off color indicator of an interior ring operating by means of a spring and ball bearing mechanism.
[0005] Other known indicator devices function by attachment to the valve stem or actuator stem. U.S. Pat. No. 5,469,805 discloses a valve position indicator fitted to the drive shaft of a valve actuator. The indicator has a sleeve interposed between an inner cylinder and an outer cylinder and arranged such that rotation of the actuator rotates the inner cylinder and causes the sleeve to slide between the inner and outer cylinders allowing a different color to be visible when the valve is open or closed.
[0006] Another known mechanism of operation for valve position indicators is by attachment of the indicator to the valve bonnet. U.S. Pat. No. 2,485,942 discloses an indicator comprised of contrasting color vanes, one affixed to the valve bonnet and the other responsive to valve stem movement. When the valve stem is moved, one vane slides over the other to indicate whether the valve is open or closed.
[0007] Each of the aforementioned inventions illustrates the disadvantages of known mechanisms for valve position indicators. These indicators operate by use of moving parts, which are additional to the valve mechanism itself. Additional moving parts not only increase costs of production, but could also potentially fail, leading possible error on the part of the operator and the need to replace the entire valve assembly.
SUMMARY OF THE INVENTION
[0008] The present invention is directed to a valve indicator wherein the open/closed position of the valve is indicated by the visible appearance of one or two bands below the hand wheel on a linear moving valve stem. Although the present invention will be described with particular reference to propane gas tank valves, it will be appreciated that the invention has broader applications and may be used with other types of valves having a valve stem that moves linearly from the open to closed position and/or in other environments. The valve indicator is for a multi-turn rotary valve, with linear moving stem. The invention is comprised of a hand wheel assembly with a hand grip having peripheral sidewalls and a downward depending annular sleeve wherein the hand wheel assembly is attached to a linear moving valve stem which operates to open and close the valve. A grommet is attached to and rests on the valve bonnet adjacent to the point where the valve stem enters the valve bonnet. As the valve is closed, the length of the valve stem shortens, drawing the annular sleeve of the hand wheel assembly down over the grommet to obscure one or more layers of the grommet's bands from vision, indicating that the valve is in the closed position. As the valve is opened, the length of the valve stem becomes longer, moving the annular sleeve of the hand wheel away from the grommet, thus exposing one or more layers of the grommet's band, indicating that the valve is in the open position. The grommet has a breakaway portion defined by a groove adjacent the periphery of the grommet, and disposed at least partially within the vertical plane of travel of the sidewalls. A connector portion in the bottom of the groove for connecting the grommet to the breakaway portion serves as a shear point. Also, an opening in the grommet has a gripping means on an inner surface adjacent the valve bonnet.
[0009] In a preferred embodiment, the indicating means of the present invention is utilized in a propane gas tank valve.
[0010] It is an object of the present invention to provide a safety feature that allows part of the visual indicating means to breakaway if blocked, so that it will not interfere with positive closure of the valve.
[0011] It is also an object of the present invention to provide a surface of the inner radius of the grommet that allows the grommet to be pressed vertically downward along the valve body, and resists being pulled vertically upward on the body.
[0012] It is an object of the present invention to provide a visual signal on a valve to indicate that a valve is open or closed.
[0013] It is a further object of the present invention to provide an indicator that is advantageously suited for use in consumer goods containing valves.
[0014] It is an additional object of the present invention to provide an inexpensive means to provide a visual valve position indication.
[0015] It is another object of the present invention to provide visual position indicating means on a valve without the addition of moving parts to facilitate manufacturing.
[0016] It is yet another object of the present invention to enhance the safety of a manual valve by providing visual indication of the valve open position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The presently preferred embodiment of the invention is disclosed in the accompanying drawings wherein:
[0018] [0018]FIG. 1 is a cross-sectional elevational view of an upper portion of a valve assembly having the features of the present invention incorporated therein;
[0019] [0019]FIG. 2 is bottom plan view depicting the features of the present invention;
[0020] [0020]FIG. 3 is a perspective view of the valve position indicator in a valve closed position;
[0021] [0021]FIG. 4 is a perspective view of the valve position indicator in a valve open position.
[0022] [0022]FIG. 5 is an elevational view of the grommet; and
[0023] [0023]FIG. 6 is a cross-sectional view of the grommet through the center.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] Referring now to the cross-sectional view in FIG. 1, there is illustrated hand wheel assembly 10 comprised of an exterior hand grip 12 with peripheral sidewalls 14 forming a recessed cavity 16 on the underside of grip 12 . Sidewalls 14 are preferably provided with a surface and shape suitable for secure manual gripping. Disposed within cavity 16 is an integral downward depending annular sleeve 18 .
[0025] Hand wheel assembly 10 is attached to a valve stem 20 by a fastener 22 . A grommet 24 is attached to the upper portion of a valve bonnet 26 . Grommet 24 may be affixed by any number of means, although preferably by an interference fit. Grommet 24 may be of a brightly contrasting color for enhanced visibility, or of a neutral or metallic color, so long as it is visible to the operator. A groove 28 may be precisely machined or otherwise formed in valve bonnet 26 corresponding to the limit of travel of stem 20 .
[0026] In the preferred embodiment, stem 20 is threadedly engaged with a valve actuator 30 . Valve 32 is actuated by rotation of hand wheel assembly 10 attached to stem 20 , causing stem 20 to move linearly in and out of valve bonnet 26 . There may be alternate means of actuating the valve other than by a threaded stem, and the present invention will accommodate any linear moving valve stem having a fixed closed position.
[0027] An annular sleeve distal end 34 projects at least as far as sidewalls 14 , and preferably slightly beyond sidewalls 14 , in order to enhance the visual contrast between sleeve 18 and the grommet 24 . Distal end 34 may be tapered outwardly to complement a beveled surface 36 of grommet 24 . Furthermore, sleeve 18 must encompass grommet 24 with a close tolerance in both the vertical and horizontal planes in order to achieve accurate indications of position. Grommet 24 must become exposed upon the slightest opening of valve 32 so as to properly indicate position. In a pressurized gas tank, fluid communication occurs upon the slightest opening of the valve seat, and a greater degree of displacement of the valve does not appreciably affect the rate of flow.
[0028] A bottom plan view of the valve indicator in valve closed position is depicted in FIG. 2. In the preferred embodiment, exterior handgrip 12 has fluted peripheral sidewalls 14 to provide a suitable gripping surface. Inside the periphery of handgrip 12 , annular sleeve 18 is projects downward to cover grommet 24 surrounding valve stem 20 .
[0029] [0029]FIG. 3 depicts the appearance of the valve position indicator when valve 32 , with an inlet 38 and an outlet 40 , is in the closed position. As valve 32 is closed, valve stem 20 , as depicted in FIG. 1, is rotated downward into a valve body 42 to its maximum point of travel. Sleeve 18 is thereby drawn toward valve bonnet 26 . When the valve seat (not shown) closes, grommet 24 is completely concealed within sleeve 18 . The disappearance of grommet 24 indicates that valve 32 is in the closed position. Grommet 24 may be colored to provide visual contrast with the metallic valve material, or of the same or similar material as the valve, so long as the grommet is visible when the valve is open.
[0030] [0030]FIG. 4 depicts the appearance of the valve position indicator when valve 32 is in the open position. As valve 32 is opened, valve stem 20 , as depicted in FIG. 1, extends as it is rotated away from valve bonnet 26 thereby moving sleeve 18 of hand wheel assembly 10 away from valve bonnet 26 to expose grommet 24 . The visual appearance of grommet 24 indicates that valve 32 is in the open position.
[0031] Referring next to FIGS. 5 and 6, a preferred embodiment of the invention shows the grommet 24 having a groove 46 scored in the grommet 24 to form a breakaway portion 44 . Groove 46 is scored in a concentric circle between the outer perimeter 52 of grommet 24 , and the hollow inner core 50 . The groove 46 preferably is scored just inside of the inner radius of annular sleeve 18 . When the valve 32 is in the closed position, the breakaway portion 44 will be in contact with, or very closely proximate to, annular sleeve 18 , such that the grommet 24 will be concealed from view by the beveled surface 36 of distal end 34 .
[0032] After repeated uses, the metal stem 20 will begin to wear, causing the position that corresponds to the valve closed position to shift slightly downward from the original closed position. The interference fit between the valve body 26 and grommet 24 will allow the grommet, in normal operation, to adjust itself in response to downward pressure applied by sidewall 18 , by sliding downward on the valve body to the new “Off” position of the valve stem. However, in the event that the grommet is frozen and fails to move with the valve operator, the breakaway portion 44 will shear away from the grommet 24 , to allow the valve to close without interference. The shear point 48 on the grommet 24 is formed at the bottom of groove 46 , at a point along the radius less than the inner radius of sleeve 18 , such that the remaining portion of grommet 24 will not interfere with the vertical travel of the sleeve. The breakaway portion provides an additional safety feature by preventing the grommet 24 from obstructing the valve 10 from completely closing. The breakage of the breakaway portion 44 serves as an indicator to the operator that the valve has worn, signaling that the valve is in need of repair or replacement, or that the visual indicating grommet 24 may need to be manually adjusted.
[0033] Referring to FIG. 6, a sawtooth surface 56 may be provided as a gripping means on the inner radius of grommet 24 to supply additional gripping strength between the grommet 24 and the valve body 26 . The sawtooth surface 56 prevents unforced slippage of grommet 24 on the valve body. The sawtooth surface 56 also ensures that the grommet 24 will not be “pulled” upward if the grommet catches on, or sticks to, the sleeve 18 .
[0034] Preferrably, the teeth in the sawtooth surface 54 have substantially horizontal top edges, and angled bottom edges, to bias movement in the downward (or valve closed) direction and resist movement in the upward (or valve open) direction. In that way, movement of the grommet will only occur one direction, downwardly, as the valve wears, and will not move upwardly under normal operation. Other surfaces may be employed as gripping means, such as a knurled surface, or other irregular finish that effectively engages the valve body. Also, the sawtooth surface may be continuous about the grommet's inner radius, or may be segmented into sawtooth sections.
[0035] As demonstrated by the detailed description of the preferred embodiment, the improved arrangement of the present invention allows the user of the valve to readily determine whether the valve is in the open or closed position. The simplistic construction achieves long-term performance of the indicator at a nominal cost of production.
[0036] According to the provisions of the patent statutes, we have explained the principle, preferred construction, and mode of operation of the invention, and have illustrated and described what we now consider to represent its best embodiments. However, it should be understood that within the scope of the appended claims and the foregoing description, the invention may be practiced, otherwise than specifically illustrated and described. | The present invention relates to a visual valve indicator comprised of a handle assembly with peripheral sidewalls attached to a linear moving valve stem for opening and closing of the valve and a grommet stratified into one or more color bands attached to and surrounding the base of the valve stem. A breakaway portion of the grommet allows the handle assembly to close if the grommet is frozen, by breaking away from the grommet. A sawtooth-edged inner radius of the grommet allows the grommet to slide one direction when pushed down by the handle assembly, if the valve is worn. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from U.S. Provisional Patent Application Ser. No. 60/753,169, filed on Dec. 22, 2005, and entitled “Syringe Pump” the contents of which are hereby fully incorporated by reference.
FIELD OF THE INVENTION
[0002] The present invention relates generally to syringe pumps, which are useful for administration of liquids to a patient by a medical pump from any size and type of syringe to a patient through a flexible tube.
BACKGROUND OF THE INVENTION
[0003] Syringe pumps are used to supply medication to a patient from a pre-filled syringe via a flexible tube or infusion line. Typically, a syringe pump applies a force to the plunger of the syringe to drive medication into the tube or infusion line at a controlled rate. The head of the plunger is generally engaged by a plunger head actuator that is movable along the axis of the syringe. The head actuator generally is movable from an extreme position at one end of the pump, where it allows a syringe to be loaded into the pump with its plunger fully extended, to an extreme position at the opposite end of the pump, where it fully depresses the plunger of the syringe. There are, however, a variety of different pumps available for propelling a drug to a patient. These pumps may differ—among other differences—in the manner and principle on which they operate. A need has been recognized in connection with providing arrangements and methods for reducing the size of syringe pumps without impacting the ability of the pump to administer liquids with high precision.
SUMMARY OF THE INVENTION
[0004] The present invention, in accordance with at least one presently preferred embodiment, overcomes the disadvantages and shortcomings of previous efforts for administering a liquid to a patient in two aspects. In the first aspect, the invention is concerned with a miniature mechanism for a syringe driver, which enables the system to be portable. In the second aspect, the invention is concerned with control sensors for the use with a high precision liquid administration pump.
[0005] For a better understanding of the present invention, together with other and further features and advantages thereof, reference is made to the following description, taken in conjunction with the accompanying drawings, and the scope of the invention will be pointed out in the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] FIG. 1 schematically illustrates the mechanics of a syringe driver in accordance with at least one embodiment of the present invention.
[0007] FIG. 2 schematically illustrates a pump in accordance with at least one embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0008] It will be readily understood that the components of the present invention, as generally described and illustrated in the Figures herein, may be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of the embodiments of the present invention, as represented in FIGS. 1 and 2 , is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention.
[0009] Reference throughout this specification to “one embodiment” or “an embodiment” (or the like) means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment.
[0010] Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.
[0011] The illustrated embodiments of the invention will be best understood by reference to the drawings. The following description is intended only by way of example, and simply illustrates certain selected embodiments of apparatus and systems that are consistent with the invention as claimed herein.
[0012] In accordance with the present invention, the syringe pump mechanics preferably comprise a screw bar and two (2) guiding bars. The guiding bars preferably reduce the friction of the actuator to minimum and assure smooth operation of the mechanics. The guiding bars, however, are preferably used in parallel for data transmission wires to the pump controller (micro controller) of the data from a micro switch mounted on the actuator, if the syringe is located on the actuator slot as preferred.
[0013] Referring to FIG. 1 , a preferred embodiment of the mechanics of a syringe driver in accordance with the present invention is shown. In this embodiment, a motor 8 turns the screw axis 9 that initiates, in both directions, the movement of actuator 10 . The motor steps which initiate the actuator movement 10 are preferably controlled by a magnet 1 and a hall effect sensor. Two independent sensors 6 are checking as well the motor movements. The guiding bars 3 and 3 A preferably act to stabilize actuator 10 , during movements, under pressure, but also preferably conduct signals of sensor 2 , indicating syringe location.
[0014] Referring now to FIG. 2 , a pump in accordance with at least one embodiment of the present invention is shown. The pump is denoted by reference numeral 19 , which is capable of being connected to a docking station (not shown). The docking station preferably has, among other features, a LED display, and the most significant data is preferably displayed on the LED display. FIG. 2 shows three sensors that are preferably used in controlling the syringe position: number 15 controls the syringe location in the syringe slot; number 13 senses the syringe diameter; and number 2 senses the syringe plunger position. An operation LED 18 preferably indicates the program status using a dual color led and number 12 depicts a key board which enables a user to set/change the programming of the pump.
[0015] In another embodiment of the present invention, the syringe pump has three sensors to detect the presence of the syringe and it's correct and safe located: a) sensor located on the actuator 2 , where the signals of the sensor are transmitted through the guiding bars 3 and 3 A shown on FIG. 1 ; b) a sensor located on the syringe location slot 15 shown on FIG. 2 ; and c) a third sensor located on the syringe holder 13 connected to a linear potentiometer activated by a spring (not shown) to sense the diameter of the syringe.
[0016] In another embodiment of the present invention, the pump is further provided with a covering (not shown), such as a door, which may be locked to protect any unauthorized access to the syringe. Any conventional locking mechanism may be used to secure the covering.
[0017] In another preferred embodiment, the present invention includes a motor 8 ( FIG. 1 ) and an encoder 6 , for rotating the screw axis and control the location of the actuator 10 .
[0018] In a further embodiment of the present invention, there is provided a motor connected to a bearing (front bearing) 7 which is connected to a screw axis 9 and two guiding bars 3 and 3 A that are connected to a second bearing (Rear Bearing) 5 . The front bearing 7 has a magnet 1 on the motor axis that counts the number of motor revolutions which are compared with the results of two independent channels counted on the encoder mounted 6 .
[0019] In another preferred embodiment of the present invention there is provided a motor 8 and a micro-controller, not shown, to control the motor revolution in order to get an improved linear delivery of the liquid and preventing pulsation effect. The micro-controller controls the motor revolutions by using the following algorithm:
a. the motor revolution is divided into a number of steps; b. The micro-controller rotates the motor, sequentially from first step to the last step of each revolution, wherein each step or a group of steps are indicating the location of syringe actuator; c. The pump output is controlled by three independent sensors which are comparing among them, results continuously; and d. The pump can detect the syringe size used using a linear potentiometer connected to the syringe holder 13 . The syringe size can be sequentially detected during the pump work or can be used for calibration to obtain the syringe size and brand.
[0024] According to another embodiment of the present invention, there is provided a dedicated flexible tube, with a pressure valve integrated, which will prevent free flow of the syringe content if pressure is not generated by the syringe actuator.
[0025] In another embodiment, the pump of the present invention may be connected to a multi-purpose docking station. Once the pump is connected to the docking station, the pump is converted into a stationary pump. The docking station preferably has a male connector—which corresponds to a female connector on the pump—and through the connector the syringe pump preferably: a) transmits the operation data to the docking station which is preferably displayed on a large and readable display; b) charges the pump's rechargeable batteries and will supply DC to the pump, while connected to electrical mains; c) transmits data to a central computer memory to create a file that can be tracked down; and d) enables connectivity to a central computer for data setting and control parameters.
[0026] Although illustrative embodiments of the present invention have been described herein with reference to the 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 affected therein by one skilled in the art without departing from the scope or spirit of the invention. | Methods and arrangements for administration of liquids to a patient by a medical pump from any size and type of syringe to a patient through a flexible tube are disclosed. Contemplated herein are methods and arrangements which permit a reduction in size of devices commonly encountered heretofore while administering liquids with high precision. While the arrangements of the present invention are of a size conducive to portability, the arrangements may also be mated with a docking station in a stationary configuration. Such a stationary configuration is preferably mounted on an IV pole. | 0 |
FIELD OF THE INVENTION
[0001] The inventions described below apply generally to wastewater treatment processes and systems that employ activated sludge. More specifically, the inventions are directed to the enhanced removal of suspended solids from a fluid stream occasioned by the application of a form of activated sludge during the treatment process.
BACKGROUND OF THE INVENTION
[0002] Typical municipal and industrial wastewater streams contain solid particles in a range of sizes and densities. During conventional treatment processes, solids of larger sizes and densities are removed from the waste stream rather easily. Often, as a primary treatment step, the wastewater is detained in a basin where the heavier particles (those having a density greater than the fluid medium carrying them) settle out of the waste stream through the effects of gravity. Smaller and lighter solids, however, remain suspended in the waste stream requiring additional physical and chemical processing for removal.
[0003] Following primary treatment, many treatment processes introduce activated sludge into the waste stream for secondary treatment including additional solids removal. As it is well known in the art, activated sludge is a natural beneficial biomass that interacts with the remaining solids in a manner that creates heavier settleable solids that are then more amenable to physical removal. Some suspended solids remain after the secondary treatment phase leaving a wastewater that it often still unsuitable for discharge or reuse.
[0004] Subsequent tertiary treatment processes such as filtration will remove additional solids, but removal is limited by the size of the openings in the filter media. To remove particles that would otherwise pass through the filtration process, conventional wastewater treatment methods call for the introduction of chemical coagulants (such as alum, ferric chloride or organic polymers) prior to filtration. Chemical coagulants interact with suspended solids binding individual particles into larger and heavier solids which can then be removed during secondary treatment.
[0005] Wastewater treatment plant operators pay a price for this chemical conditioning. The complex polymer chemicals add significantly to the cost of treatment. Additionally, the chemical sludge that is then collected on the filter can quickly clog or “blind” the filter media, requiring frequent, possibly continuous backwashing. This can occur because the combination of the coagulants with the wastewater constituents can create a viscous mat on the filter media. Excessive backwashing reduces the quantity of wastewater that can be treated resulting in either the purchase and installation of more treatment equipment or a reduction in the processes that produce the wastewater. Additionally, the solids removed from the system following chemical addition create a chemical sludge that is more expensive and more difficult to dispose of.
[0006] Therefore a method and apparatus for removing suspended solids from a waste stream that reduces or eliminates the need for chemical conditioning is desirable, as well a method and apparatus that is effective at small particle removal that reduces the effect of blinding filter systems and produces a solid waste that is easier to dispose than existing chemical sludges.
[0007] The inventions described below reduce or eliminate the need for chemical conditioning of wastewater by reintroducing readily available activated sludge to the treatment process after secondary treatment. An advantage of this method is that activated sludge provides a natural coagulant without the expense of chemical addition as suspended solids are adsorbed onto the activated sludge. The natural waste solids avoid the problems of heavy chemical concentrations and are thus more readily disposable.
[0008] Definition of Terms
[0009] The following terms are used in the claims of the patent and are intended to have their broadest meaning consistent with the requirements of law:
[0010] coagulation—the agglomeration of small, dispersed solids into larger particles more amenable to settling or filtration.
[0011] Where alternative meanings are possible, the broadest meaning is intended. All words in the claims are intended to be used in the normal, customary usage of grammar and the English language.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] [0012]FIG. 1 is a process diagram of a conventional wastewater treatment facility that employs primary, secondary and tertiary treatment techniques.
[0013] [0013]FIG. 2 is a modified process diagram according to the invention where activated sludge is introduced prior to filtration.
[0014] [0014]FIG. 3 is a profile view of a filtration basin using rotating disk filters.
[0015] [0015]FIG. 4 is a partial process diagram of secondary and tertiary treatment stages with an aerated return activated sludge basin.
[0016] [0016]FIG. 5 is a process diagram of a pretreatment process for an equalization basin directed to the removal of algal solids.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] Set forth below is a description of what is currently believed to be the preferred embodiment or best example of the invention claimed. Future and present alternatives and modifications to this preferred embodiment are contemplated. Any alternatives or modifications which make insubstantial changes in function, in purpose, in structure or in result are intended to be covered by the claims of this patent.
[0018] In a conventional wastewater treatment process that is known in the art (see FIG. 1), a wastewater influent 1 is introduced to a primary clarification basin 2 . In the primary clarification basin 2 , some of the solids that are entrained in the influent 1 settle by gravity to the bottom of the basin 2 . This solids separation process produces a primary effluent 3 that is introduced into a secondary treatment basin 4 , and a mass of settled solids 15 that are removed from the bottom of the primary basin 2 and disposed. In one method of secondary treatment known in the art, the secondary basin contains an activated sludge biomass that is aerated and suspended in the secondary basin. The primary effluent 3 mixes with the activated sludge of the secondary basin 4 creating additional settleable solids entrained in a secondary effluent 5 .
[0019] The secondary effluent 5 flows into a secondary clarifier 6 where additional solids are separated from the remaining effluent. In either the secondary treatment basin 4 or the secondary clarifier 6 , chemical coagulants 14 such as alum, ferric chloride or organic polymers are added to aid in settling entrained solids from the secondary effluent 5 . Solids separation in the secondary clarifier 6 results in a secondary effluent stream 7 and a waste activated sludge stream 8 . A portion of the waste activated sludge 8 flows into a return activated sludge line 9 which is diverted to the upstream side of the secondary treatment basin 4 or reintroduced into the primary effluent 3 . The remaining solids 10 from the waste activated sludge stream 8 are collected and disposed.
[0020] For further solids removal, particularly for small particle size and low density solids, the secondary effluent stream 7 flows into a tertiary treatment process such as a filtration basin 11 . In the example of FIG. 1, the filtration basin contains rotating cloth filters 12 that retain solids above a given particle size on the exterior of the filter 12 while allowing liquid and smaller entrained solids to pass through. The tertiary effluent 13 is discharged to a receiving water. Solids are removed from the filters 12 and collected as a filtered solids waste stream 10 which is disposed in a similar manner as other waste solids.
[0021] In a preferred embodiment of the invention (see FIG. 2), no chemical coagulants 14 are introduced during the treatment process. In lieu of chemical coagulants 14 , a return activated sludge feeder 24 is introduced into the secondary effluent stream 7 or, alternatively, into the tertiary treatment basin 11 . It is preferred that this return activated sludge feeder 24 runs continuously through a closed conduit in fluid communication with the secondary effluent stream 7 . However, it is also recognized as within the scope of the invention to apply the return activated sludge feeder 24 in batches. The preferred final concentration of return activated sludge in the tertiary treatment basin 11 is 2-5 milligrams per liter.
[0022] The return activated sludge feeder in the tertiary treatment basin 11 acts as a natural flocculent and adsorbs small solids on the biomass. The wastewater in the tertiary treatment basin 11 , thickened by the addition of return activated sludge, forms a beneficial cake 17 on the exterior of the filters 12 (see FIG. 3). Since the cake 17 does not have the deleterious characteristics of sludges bearing chemical coagulants, it also acts as a supplemental filter improving solids removal in the tertiary treatment basin 11 . To the extent that the return activated sludge feeder 24 replaces the addition of chemical coagulants 14 , the net amount of solids generated during tertiary treatment does not increase.
[0023] In an alternative embodiment (see FIG. 4), the return activated sludge needed for tertiary treatment is stored in an aerated tank 16 adjacent to the tertiary treatment basin 11 . It is recognized that whether the return activated sludge is fed continuously or in batches, electronically controlled valves and other instrumentation as known in the art may be installed to automate the process.
[0024] The inventions apply to treatment basins of any size or shape. It is also recognized that the invention is equally effective for activated sludge treatment systems where two or more of the treatment stages are combined, where one or more stages is omitted, or in sequencing batch reactors. The preferred return activated sludge concentration of 2-5 milligrams per liter does not disclaim higher or lower concentrations. The preferred concentration has been selected for typical domestic wastes. It is recognized that a typical domestic wastes, commercial wastes and industrial wastes will require limited experimentation to determine the optimal concentration for each application. While in many cases no chemical coagulants 14 are needed, it is also within the scope of the invention to introduce chemical coagulants 14 in quantities lower than conventional treatment practices in combination with the return activated sludge feeder 24 addition to obtain the claimed benefits.
[0025] In an alternative application of the invention (see FIG. 5), the addition of activated sludge can be used for the preconditioning of algal solids prior to filtration. In a typical system, a non-potable water held in a lagoon 26 or retention pond may develop blooms of algae from the quiescent hydraulic condition and available nutrients. As a substitute for a chemical algaecide, an activated sludge feeder 25 is added to the lagoon effluent 21 . The effluent 21 flows into a mixing basin 18 where the return activated sludge interacts with the solids and nutrients to produce a mixed effluent 22 which passes through a clarifying tank 27 to regulate the solids concentration. Excess solids are directed through a return line 28 to the lagoon 26 for additional processing. It is preferred that the activated sludge concentration in the mixed effluent 22 be maintained in the range of 5-10 milligrams per liter. Although this concentration is preferred for typical municipal waste streams, it is recognized that both higher and lower concentrations are contemplated by the invention. The most effective activated sludge concentration for any specific application must be tailored to the specific characteristics of the waste stream being treated.
[0026] The mixed effluent 22 flows into a pre-filtration basin 19 containing filter media such as rotating disk filters 12 . The return activated sludge in the mixed effluent 22 acts as a natural flocculent and adsorbs small algal solids on the biomass. The wastewater in the pre-filtration basin 19 , thickened by the addition of return activated sludge, forms a beneficial cake 17 on the exterior of the filters 12 . The pre-filtration process produces a pre-treated effluent 20 that can be directed to the plant's headworks for additional treatment or to a receiving water. Waste solids 10 are disposed in a conventional manner as is known in the art.
[0027] The above description is not intended to limit the meaning of the words used in the following claims that define the invention. Rather, it is contemplated that future modifications in structure, function or result will exist that are not substantial changes and that all such insubstantial changes in what is claimed are intended to be covered by the claims. | In a wastewater treatment process involving activated sludge, the invention provides a method for improving suspended solids removal without the need for chemical coagulants. Improved solids removal is obtained through the reintroduction of return activated sludge as a natural flocculent prior to tertiary filtration. In some applications algal solids can be pre-filtered from equalization or detention ponds and lagoons by return activated sludge addition followed by mixing and high solids filtration. The inventions result in improved solids removal and longer run times for the treatment processes with reduced need for chemical coagulants. | 2 |
The present application is a continuation application of Ser. No. 282,854 filed Dec. 9, 1988, now abandoned, which was a continuation of S.N. 047,388 filed May 8, 1987, now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to a novel and useful knit or woven fabric. More particularly, the present invention relates to a braid of raw silk, as well as a knit or woven fabric that employs such a braid and which is improved in such characteristics as warmth, moisture absorption, comfort, air permeability, wear resistance and luster.
The use of raw silk as a textile fiber predates written history. The continuous filaments unwound from cocoons are degummed and twisted together to form multifilament yarns which are then woven into a fabric form. Because of the nature of raw silk, the twisted silk yarns will project outwardly in a loop when slackened. This phenomenon is not deleterious to the purpose of making a woven fabric but in knitting operations, needles will get stuck by the loop and may break. In order to avoid the occurrence of frequent troubles on a knitting machine due to the looping of silk yarns, the machine has to be operated at a speed at least ten times slower than when it is used to knit cotton or nylon yarns. Another problem associated with the knitting silk yarns is that holes sometimes occur in the fabric to reduce the yield of acceptable products. For these principal reasons, no commercial production of knit fabrics is currently undertaken on the basis of raw silk. Further, textile fabric made from the knitting have been disadvantageous in that a surface of the fabric may have an undesirable striped pattern.
SUMMARY OF THE INVENTION
The present inventors made concerted efforts to develop a knit or woven fabric that can be produced from raw silk on a commercial scale and found that this object can be attained by a knit or woven fabric that employs a tubular braid made from raw silk which is optionally blended with other fibers. The present invention has been accomplished on the basis of this finding.
DETAILED DESCRIPTION OF THE INVENTION
The raw silk used in the present invention may be any of the known types of silk such as silk, Tussah silk, Moga silk, Eria silk and Yamamai silk. In addition to silk, Tussah silk and Moga silk which are currently produced in large quantities are preferably used as raw silk in the present invention. Such a raw silk may be blended with other fibers except raw silk such as synthetic fibers (e.g. nylon, polyester, polyamide, polyurethane, acrylic and acetate) and natural fibers (e.g. cotton and hemp). The braid which is employed in the fabric of the present invention is made by intertwining at least three, preferably 3-50, more particularly 6-32, in number of filaments of raw silk into a tubular form. The term "tubular form" means a hollow structure whose peripheral wall is formed of intertwined filaments of raw silk and which has a round (e.g. circular or elliptical) cross section in its radial direction. The braid is composed of a set of fibers that cross each other by running at oblique angles with respect to its longitudinal direction, the fibers preferably crossing each other as they run as if they were threads of left- and right-hand screws.
If raw silk is used as the sole component of the braid, its deguming may be effected either before or after the braid is made. If raw silk is blended with other kind of fibers, it is preferably deguming and processed into a silk yarn before braiding. Braids solely made of war silk may be knitted or woven to make an all silk-fabric. From an economic viewpoint and in order to incorporate the features of various fibers, braids which are a blend of raw silk and other fibres may be employed to make a knit or woven fabric. The blending ratio of raw silk to other fibers ranges from 10:90 to 100:0 (wt%), preferably from 50:50 to 99.1:0.1.
Braiding may be achieved with any of the knitting machines that are conventionally used to make braids from cotton or synthetic fiber yarns, and an example is a circular knitting machine intended to make 4-,8- or 16-th stitch braids. The tubular braid used in the present invention has no elongation in its longitudinal direction (parallel to its axis) and is pliable to a force that acts in its transversal (radial) direction Because of these mechanical properties, the braid when used as a textile yarn will neither slack on a knitting machine nor project laterally in a loop form. Instead, the braid will have smooth engagement with needles and permits the machine to be operated with needles and permits the machine to be operated at a faster speed without breaking the needles.
The braid used in the present invention has a fineness that ranges from 56 to 1,000 den (deniers), preferably from 120 to 600 den. Therefore, the finest braid will be formed from four filaments of 14 den each (4×14 den=56 den) and other combinations will produce larger braids having varying thicknesses. Most preferably, 6-32 filaments of 21-70 den are intertwined to make a single braid. A plurality of the resulting braids are processed into knit or woven fabrics by means of conventional knitting or weaving machines.
The knit or woven fabric of the present invention is chiefly used as a garment. The term "knit fabric" as used herein includes within its definition hosiery, sweaters, cardigans, boleros, jackets, pullovers, suits, vests, coats, foundations, underwear (e.g. under-shirt and under-shorts), blouses, leggings, skirts, tights, wedding dresses, shirts, trunks, pants, trousers, clothes in general, overcoats, mufflers, scarfs, gloves, caps, hats, neckties, sanitary materials, bathing suits, etc. The term "woven fabric" as used herein includes in its category Kimono (Japanese cloths), Haori (Japanese half-coat), coats, neckties, etc.
Using tubular braids, the knit or woven fabric of the present invention presents a particularly good luster and provides efficient air permeation. In addition, this fabric is far superior in moisture absorption, warmth, wear resistance and comfort as compared with the conventional product made from twisted silk yarns. These advantages of the fabric of the present invention become particularly noticeable when it is a knit fabric.
The following example and comparative example are provided for the purpose of further illustrating the present invention but are in no sense to be taken as limiting.
EXAMPLE 1
A plurality of all silk cylindrical braids (400 den) were processed on a knitting machine (14 gage) to form a fabric for sweater at a speed of 7cm/min. The yield of acceptable products was 90%. The sweater produced form the resulting fabric was highly lusterous, had good air permeability, moisture absorption, heat insulation and wear resistance, was light and warm, and comfortable to wear. This fabric did not have a striped pattern on the surface thereof.
COMPARATIVE EXAMPLE 1
Twisted silk yarns (400 den) were processed into a fabric for sweater on a knitting machine which was of the same type as used in Example 1 but which was operated at a speed twelve times as slow as the usual speed. The yield of acceptable products was only 40 %. This fabric did have a striped pattern. | A knit or woven fabric that can be produced from raw silk on a commercial scale and found that this object can be attained by a knit or woven fabric that employs a tubular braid made from raw silk which is optionally blended with other fibers. The present invention has been accomplished on the basis of this finding. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. application Ser. No. 12/899,155 filed Oct. 6, 2010, now U.S. Pat. No. 8,418,907, which claims benefit of Provisional application No. 61/258,246 filed Nov. 5, 2009, and the disclosures of each of the above-identified applications are hereby incorporated by reference in their entirety.
BACKGROUND
1. Technical Field
The present disclosure relates to a surgical stapling device and more particularly to a surgical stapling device having an adjustable staple firing mechanism.
2. Background of the Related Art
There are several known types of surgical stapling instruments specifically adapted for use in various procedures. In many such surgical devices, tissue is first grasped or clamped between opposing jaw structures and then joined by surgical fasteners. The fasteners are typically in the form of surgical staples. These staples generally include a pair of legs adapted to penetrate tissue and connected by a backspan from which they extend. In use, the staples are formed to a “B” configuration. Two-part fasteners are also known and include legs that are barbed and connected by a backspan which are engaged and locked into a separate retainer piece that is usually located in the anvil. In some devices, a knife is provided to cut the tissue which has been joined by the fasteners.
In these devices, one of the jaw structures carries a staple cartridge having one or more laterally spaced rows of staples, which are aligned with corresponding rows of anvil depressions on an opposing jaw structure. The tissue is initially gripped or clamped such that individual staples can be ejected from the cartridge, through the slots, and forced through the clamped tissue. The staples are ejected by longitudinal movement of a driver and forced through the clamped tissue, forming against the staple forming depressions of the anvil. The staples can be arranged in a linear or non-linear row.
A common issue in transecting tissue and/or in anastomosis procedures employing the surgical stapling instruments is the balance between anastomotic strength and the degree of hemostasis achievable. It is known to include different size staples in a surgical stapling instrument having a constant gap (uniform distance) between an anvil and a staple cartridge.
A common concern in these surgical procedures is hemostasis, or the rate at which bleeding of the target tissue is stopped. It is commonly known that by increasing the amount of pressure applied to a wound, the flow of blood can be limited, thereby decreasing the time necessary to achieve hemostasis. To this end, conventional surgical fastening apparatus generally apply two or more rows of fasteners about the cut-line to compress the surrounding tissue in an effort to stop any bleeding and to join the cut tissue together. Each of the fasteners will generally apply a compressive force to the tissue sufficient to effectuate hemostasis, however, if too much pressure is applied, this can result in a needless reduction in blood flow to the tissue surrounding the cut-line. Accordingly, the joining of tissue together in this manner may result in an elevated level of necrosis, a slower rate of healing, and/or a greater convalescence. On the other hand, if not enough pressure is applied, proper hemostasis may not be achieved.
Consequently, it would be advantageous to provide a surgical fastening apparatus capable of adjusting the application of staples to accommodate different tissue thicknesses.
SUMMARY
The present disclosure relates to camming members adjustable to different levels depending on tissue thickness. In one aspect, the present disclosure provides a surgical fastener applying apparatus comprising a cartridge section having a cartridge containing a plurality of fasteners and an anvil section having an anvil for receiving the fasteners when advanced from the cartridge. The cartridge and anvil sections clamp tissue therebetween. A cam member is slidable within the cartridge section to fire the fasteners, and has a first position defining a first distance from the anvil section and movable to a second position defining a second different distance from the anvil section. A cam adjusting member operably associated with the cam member moves the cam member from the first position to the second position in response to a thickness of tissue clamped between the anvil and cartridge sections.
In another aspect, a surgical fastener applying apparatus is provided comprising a cartridge section having a cartridge containing a plurality of fasteners and having a tissue contacting surface and an anvil section having an anvil for receiving the fasteners when advanced from the cartridge. The cartridge and anvil sections clamp tissue therebetween. A cam member is movable between a first position defining a first distance from the tissue contacting surface of the cartridge and a second position defining a second position defining a second different distance from the tissue contacting surface. The cam member is automatically movable from the first position to the second position in response to the thickness of tissue clamped between the anvil and cartridge sections.
BRIEF DESCRIPTION OF THE DRAWINGS
Various embodiments of the present disclosure are described hereinbelow with references to the drawings, wherein:
FIG. 1 is a perspective view of one embodiment of the surgical stapler having a fastener firing mechanism of the present disclosure;
FIG. 2 is an exploded view of a cartridge assembly of the present disclosure including a portion of the firing mechanism;
FIG. 3 is a close up view of the cam members and cam adjustment assembly of FIG. 2 ;
FIG. 4 is a transverse cross-sectional view of a portion of the cartridge assembly showing the cam members at a first position for application of staples to thinner tissue;
FIG. 5 is a transverse cross-sectional view of the cartridge and anvil assemblies showing the cam members at the position of FIG. 4 and the cartridge and anvil clamping the tissue, prior to firing of the staples;
FIG. 6 is a view of a portion of the cartridge and anvil assemblies in partial cross section illustrating the cam member in the position of FIG. 4 and in the pre-fired position before contact with a staple pusher;
FIG. 7 is a cross-sectional view similar to FIG. 5 showing advancement of the staples through body tissue and into contact with anvil pockets of the anvil assembly;
FIG. 8 is a view similar to FIG. 6 showing advancement of the cam member into contact with the staple pusher to advance the staple for deformation against the anvil;
FIG. 9 illustrates the staple formed around a thinner tissue section corresponding to the position of the cam members in FIGS. 4-8 ;
FIG. 10 is a transverse cross-sectional view of the cartridge and anvil assemblies similar to FIG. 7 showing the cam members in a second position for application of staples to thicker tissue;
FIG. 11 is a view of a portion the cartridge and anvil assemblies in partial cross section illustrating the cam member in the position of FIG. 10 and showing advancement of the cam member into contact with the staple pusher to advance the staple for deformation against the anvil;
FIG. 12 illustrates the staple formed around a thicker tissue section corresponding to the position of the cam members in FIGS. 10 and 11 ;
FIG. 13 is a transverse cross-sectional view of the cartridge and anvil assemblies similar to FIG. 10 showing the cam members in a third position for application of staples to even thicker tissue;
FIG. 14 is a view of a portion of the cartridge and anvil assemblies in partial cross section illustrating the cam member in the position of FIG. 13 and showing advancement of the cam member into contact with the stapler pusher to advance the staple for deformation against the anvil;
FIG. 15 illustrates the staple formed around a thicker tissue section corresponding to the position of the cam members in FIGS. 13 and 14 ;
FIG. 16 is an exploded view of the cam members and cam adjustment assembly of an alternate embodiment of the present disclosure;
FIG. 17 is a transverse cross-sectional view of a portion of the cartridge assembly of the embodiment of FIG. 16 showing the cam member at a first position for application of staples to thinner tissue;
FIG. 18 is a view similar to FIG. 17 showing the cam member at another position for application of staples to thicker tissue;
FIG. 19 is a perspective view of another surgical stapler having a fastener firing mechanism of the present disclosure.
DETAILED DESCRIPTION OF EMBODIMENTS
Embodiments of the presently disclosed stapler will now be described in detail with reference to the drawings wherein like numerals designate identical or corresponding elements in each of the several views. As is common, the term “proximal” refers to that part or component closer to the user or operator, i.e. surgeon or physician, while the term “distal” refers to that part or component further away from the user.
FIG. 1 illustrates one type of surgical stapler that can incorporate the cam bar/pusher arrangement of the present disclosure. The surgical stapler 10 has a cartridge half section 12 , an anvil half section 14 , and handles 15 and 16 for facilitating clamping of the sections 12 and 14 . Cartridge half section 12 has a channel 47 ( FIG. 2 ) to receive cartridge 32 which includes a plurality of staples 60 and a plurality of staple pushers 36 to advance the staples 60 from the cartridge 32 through slots 52 .
The staple firing mechanism includes a cam bar assembly which is advanced by distal advancement of manual firing lever 28 ( FIG. 1 ). The cam bar assembly is slidable for longitudinal advancement in the cartridge 32 to advance the pushers 36 in a direction substantially transverse to the longitudinal axis of the stapler and substantially transverse to the direction of movement of the camming members. Engagement of the pushers 36 by the cam members advances the staples 60 through the tissue and into contact with the anvil depressions (pockets) 22 ( FIG. 5 ) of the anvil half section 14 . In the illustrated embodiment of FIG. 2 , there are two staggered linear rows of staple slots 52 formed on either side of a knife slot 58 which guides a knife bar 50 with knife blade 51 between the rows of staples 60 . A different number of rows can be provided and a knife can optionally not be provided. A single staple 60 is positioned in each of the slots 52 . Staple pushers 36 are aligned with each slot 52 so that preferably a single staple pusher 36 is positioned under the staple 60 retained in the slot 52 . The pushers 36 can optionally be attached to each other in groups of two offset oriented pusher pairs. More details of the stapler are disclosed in U.S. Pat. No. 7,140,527, issued Nov. 28, 2006, and U.S. Pat. No. 7,055,730, issued Jan. 6, 2006, the entire contents of each of these applications are incorporated herein by reference.
With reference to FIGS. 2 and 3 , the cam member arrangement of the present disclosure will now be described. Cam member support or sled 38 includes a pair of outer camming elements 39 a and a pair of inner camming elements 39 b . An upper pair of projecting ribs or teeth 56 a (only one of which is shown in the view of FIG. 3 ) are positioned on opposing sides of the support 38 . A lower pair of ribs or teeth 56 b (only one of which is shown in the view of FIG. 3 ) are positioned on opposing sides of the support 38 . The outer camming elements 39 a and inner camming elements 39 b are preferably axially staggered as shown, i.e. the inner camming elements 39 b are positioned slightly distally of outer camming elements 39 a.
Cam adjusting members 34 and 35 extend through slots 54 a 54 b , respectively in cartridge 32 and are biased upwardly (toward tissue contacting surface 33 of cartridge 32 ) by springs 36 a , 36 b and 37 a , 37 b , respectively. Cam adjusting member 35 has a projecting tab 35 a at a proximal end engageable with pivot arm 48 . Cam adjusting member 34 has a projecting tab 34 a at a proximal end for engagement with pivot arm 42 . The opposite surface (upper surface as viewed in the orientation of FIG. 2 ) of cam adjusting member 35 has a tissue contacting surface 35 b with an extended planar surface forming a T-shape. Similarly, the opposite surface of cam adjusting member 34 has a tissue contacting surface 34 b forming a T-shape. The surfaces 34 b , 35 b come into contact with and compress the tissue when the anvil and cartridge sections 14 , 12 are approximated to clamp tissue therebetween.
The cam adjusting members 34 , 35 adjust in the distance they protrude from the slots 54 a , 54 b , depending on tissue thickness. This can be seen for example by comparing FIGS. 5, 10 and 13 . When the tissue is relatively thin as shown in FIG. 5 , the cam adjusting members 34 , 35 will protrude a distance X beyond the tissue contacting surface 33 of cartridge 32 . When encountering thicker tissue clamped between the cartridge and anvil sections 12 , 14 as in FIG. 10 , the cam adjusting members 34 , 35 will protrude a shorter distance Y from the tissue contacting surface 33 of the cartridge 32 . In FIG. 13 , even thicker tissue is encountered such that the cam adjusting members 34 , 35 barely protrude from the slots 54 a , 54 b as the T-surfaces 34 b , 35 b are positioned on the tissue contacting surface 33 . As can be appreciated, as thicker tissue is encountered and clamped between the anvil 20 and cartridge 32 , the clamped tissue applies an inward force toward the cartridge 32 (or downward as viewed in the orientation of FIGS. 5, 10 and 13 ) on the T surface 34 b , 35 b of cam adjusting members 34 , 35 . Such downward force causes pivot arms 42 , 41 and 48 , 40 to pivot to change the pusher contact position of the cam elements 39 a , 39 b as described in detail below. As can be appreciated, the terms upward and downward refer to the orientation of the stapler/components shown in the Figures, it being understood that if the orientation of the stapler/components changes, the upward and downward references would likewise change.
With reference to FIGS. 3, 4 and 5 , pivot arm 42 has an outer region 42 a which is in contact with a lower surface of tab 34 a of camming element 34 . In the normal position, the cam adjustment element 34 is in its upward position with surface 34 furthest from the tissue contacting surface 33 of cartridge 32 due to the biasing force of springs 36 a , 36 b . First pivot arm 42 engages second pivot arm 41 which is attached to, or alternatively in abutment with, the sled 38 at inner region 41 b . When surface 42 a of tab 34 forces inner region 42 a of pivot arm 42 downwardly, pivot arm 42 pivots about pin 42 c (counterclockwise as viewed in FIG. 5 ). Such pivotal movement causes inner region 42 d to engage outer region 41 d of second pivot arm 41 , causing arm 41 to pivot about pin 41 c (clockwise as viewed in FIG. 5 ) so that inner region 41 b is forced in a direction toward the sled 38 (downwardly as viewed in the orientation of FIG. 5 ). Such movement of inner region 41 b forces sled 38 in a direction away from the tissue contacting surface 33 (downwardly as viewed in FIGS. 4 and 5 ). This changes the plane in which the sled 38 travels to contact the staple pushers 36 . Ribs 56 a , 56 b of sled 48 are forced out of the upper retaining or locking recesses 49 a , 49 b formed in the inner wall of cartridge 32 and are moved to engage different (lower) retaining recesses at a different “level” of the sled 38 .
Similarly, with reference to FIGS. 3 and 5 , first pivot arm 48 has an outer region 48 a which is in contact with a surface of tab 35 a of cam adjustment member 35 . In the normal position, cam adjustment member 35 is in its upward position with tissue engagement surface 35 b furthest from tissue contacting surface 33 of cartridge 32 due to the biasing force of springs 37 a , 37 b . First pivot arm 48 engages second pivot arm 40 which is attached to, or alternatively in abutment with, the sled 38 at inner region 40 b . When outer region 48 a is forced downwardly by tab 34 a , first pivot arm 48 is pivoted about pin 48 c (clockwise as viewed in FIG. 5 ) such that inner region 48 c engages outer region 40 d of second pivot arm 40 . This forces arm 40 to pivot about pin 40 c (counterclockwise as viewed in FIG. 5 ), causing inner region 40 b to apply a downward force to sled 38 , thereby forcing sled 38 in a direction away from the tissue contacting surface 33 (downwardly as viewed in FIG. 5 ). This, in conjunction with pivot arms 41 , 42 changes the plane in which the sled 38 travels to contact the staple pushers 36 . Ribs 56 a , 56 b are forced out of the retaining or locking recesses 46 a , 46 b and 49 a , 49 b formed in the inner wall of cartridge 32 and moved to engage different (lower) locking recesses e.g. recesses 46 c , 46 d and 49 c , 49 d . This different position is shown in FIG. 10 .
In FIG. 13 , the first pivot arms 48 , 41 have pivoted even further, due to the force of the thicker tissue on cam adjusting members 34 , 35 , causing respective second pivot arms 41 , 40 to pivot further, applying an additional force on the sled 38 , thereby forcing it further from tissue contacting surface 33 than in FIG. 10 , with the ribs 56 a , 56 b engaging lower recesses 46 e , 46 f and 49 e , 49 f of the cartridge 32 . As can be appreciated, when the sled 38 is closer to the tissue contacting surface 33 , (for thinner tissue) the camming elements 39 a , 39 b are closer to the staple pushers 36 so that their advancement will force the staples further out from the respective slots 52 into engagement with the anvil. This is shown in FIGS. 6, 8 and 9 where the staple 60 forms a smaller tissue enclosure area, e.g. a tighter B shape. When the sled 38 is further from the staple pushers 36 due to thicker tissue, the camming elements 39 a , 39 b are further from the staple pushers 36 , due to the changed position (level) of the sled 38 , and thus the angled camming surfaces contact the pushers 36 at a different (lower) region. Thus, the staples 60 will form with a larger tissue enclosure space as shown in FIGS. 11 and 12 . When even thicker tissue is encountered, the camming elements 39 a , 39 b will be located even a further distance from staple pushers 36 , contacting the pushers at a still lower region, so that the staples 60 will form an even larger tissue enclosure area to accommodate the thicker tissue. This is illustrated in FIGS. 14 and 15 . Stated another way, the angled camming surfaces 55 a , 55 b of the camming elements 39 a , 39 b will contact a different curved contacting region of the staple pushers 36 , depending on the position (level) of sled 38 with respect to the pushers 36 of cartridge 32 .
FIG. 16-18 illustrate an alternate embodiment of the present disclosure for adjusting the plane of the sled and camming elements. In this embodiment, a linkage mechanism is provided to adjust the “level” of the sled in response to tissue thickness. More specifically, a sled 138 has a pair of outer camming elements 139 a and a pair of inner camming elements 139 b , having respective angled camming surfaces 155 a , 155 b , configured for engagement with staple pushers to advance staples out of the cartridge in the same manner as described above with the embodiment of FIGS. 1-15 . The linkage mechanism includes a rocker arm 162 , a pivot arm 160 with an arcuate region 161 and a connector 165 . Rocker 162 has a transverse aperture 162 a to receive locking pin 164 which also extends through opening 165 a in connector 165 . The curved outer surface 165 b of connector 165 is seated within arcuate region 161 of pivot arm 160 . Curved end 162 b of rocker 162 is received within opening 134 c of tab 134 a of cam adjusting element 134 .
Similarly, pivot arm 170 has an arcuate region 171 . Rocker 172 has a transverse aperture 172 a to receive locking pin 174 which also extends through opening 175 a in connector 175 . The curved outer surface 175 b of connector 175 is seated within arcuate region 171 of pivot arm 170 . Curved end 172 b of rocker 172 is received within an opening of a tab of a second cam adjusting member (not shown) identical to cam adjusting member 134 .
Sled 138 has ribs or teeth 156 a , 156 b on opposing sides which are identical in structure and function to the ribs 56 a , 56 b of sled 38 of FIG. 2 and engages locking recesses in the cartridge to retain the sled in its radial position in the same manner as described above with sled 38 . In use, sled 138 is automatically adjustable based on the tissue thickness. This occurs as the cam adjusting members are forced away from the tissue contacting surface of the cartridge when encountering thicker tissue (in the same manner as described above for cam adjusting members 34 , 35 ). When forced away from the tissue contacting surface of the cartridge, they apply an inward force (downwardly in the orientation of FIGS. 16-18 ) on rockers 162 (and rocker 172 ), causing it to pivot as seen in FIG. 18 . Note FIGS. 17 and 18 show movement of one of the linkage mechanisms (rocker 162 , pivot arm 160 , etc.), it being understood that rocker 172 , pivot arm 170 and connector 175 of the other linkage mechanism operates in a similar manner. This pivoting of the rocker 162 forces connector 165 upwardly, forcing the end 167 of pivot arm 160 upwardly so that it rotates clockwise about the support pin 174 so the inner end 169 (attached to or abutting sled 138 ) applies a downward force on the sled 138 . For brevity, only the two extreme positions of the sled 138 are shown, with FIG. 17 showing the sled 138 in its uppermost position, closest to the tissue contacting surface of the cartridge for thinner tissue, and FIG. 18 showing the sled 138 in its lowermost position, furthest from the tissue contacting surface of the cartridge to adjust for thicker tissue. Note spring 170 , connector 175 , and rocker 172 act in a similar manner to adjust the position of the sled 18 , applying a force on a second region of the sled by end 179 ( FIG. 16 ) of pivot arm 170 which is attached to or in abutment with sled 138 .
As can be appreciated with reference to the Figures, the difference in location or “level” of the sled 38 , 138 , i.e. position on different planes, enables the instrument to automatically adjust to tissue of different thickness. That is, the tissue thickness itself dictates the position of the cam adjustment members which in turn controls the position of the sled 38 , 138 . The position of the sled 38 , 138 in turn affects the extent of deployment of the staples 60 due to the varied position of the angled camming surfaces of the camming members 39 a , 39 b , 139 a , 139 b which contact the staple pushers. Accordingly, the extent of staple deployment is automatically determined by the tissue thickness.
It should be appreciated that although three discrete positions of the sled are illustrated, a different number of positions are contemplated, including an infinite number of variations of the planes of the sled.
It should be appreciated that the adjustable planes for the camming elements of the present disclosure can also be used with other staplers, including, but not limited to other linear staples and endoscopic linear staplers. This cam arrangement can be used for example with the endoscopic surgical stapler 200 of FIG. 19 , which has an elongated tubular portion 212 , an anvil assembly 214 pivotally mounted at a distal end portion of the elongated tubular portion 212 and a cartridge assembly 220 . The anvil and cartridge assemblies 214 , 220 are moved into approximation to clamp tissue therebetween. A handle 230 is squeezed to clamp the anvil and fire the staples in the manner disclosed in U.S. Pat. Nos. 5,762,256 and 5,865,361, the entire contents of which are incorporated by reference.
Although described for fastener applying apparatus for firing staples formed by an anvil, the camming elements of this disclosure could also be used in fastener applying apparatus for firing two part fasteners.
While the above description contains many specifics, these specifics should not be construed as limitations on the scope of the present disclosure, but merely as illustrations of various embodiments thereof. Therefore, the above description should not be construed as limiting, but merely as exemplifications of various embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the disclosure. | A surgical fastener applying apparatus comprising a cartridge section having a cartridge containing a plurality of fasteners and an anvil section having an anvil for receiving the fasteners when advanced from the cartridge. The cartridge and anvil sections clamp tissue therebetween. A cam member is slidable within the cartridge section to fire the fasteners, and is movable from a first position defining a first distance from the anvil to a second position defining a second different distance from the anvil. A cam adjusting member is operably associated with the cam member and moves the cam member from the first position to the second position in response to a thickness of tissue clamped between the anvil and cartridge sections. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation-in-part of prior U.S. patent application Ser. No. 09/635,511, filed on Aug. 9, 2000, which claims priority from U.S. Provisional Patent Application No. 60/147,894 filed on Aug. 9,1999, and are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] Embodiments of this invention relate to a method and device for improving cardiac function.
[0004] 2. Discussion of Related Art
[0005] Congestive heart failure annually leads to millions of hospital visits internationally. Congestive heart failure is the description given to a myriad of symptoms that can be the result of the heart's inability to meet the body's demand for blood flow. In certain pathological conditions, the ventricles of the heart become ineffective in pumping the blood, causing a back-up of pressure in the vascular system behind the ventricle.
[0006] The reduced effectiveness of the heart is usually due an enlargement of the heart. A myocardial ischemia may, for example, cause a portion of a myocardium of the heart to lose its ability to contract. Prolonged ischaemia can lead to infarction of a portion of the myocardium (heart muscle) wherein the heart muscle dies and becomes scar tissue. Once this tissue dies it no longer functions as a muscle and cannot contribute to the pumping action of the heart. When the heart tissue is no longer pumping effectively, that portion of the myocardium is said to be hypokinetic, meaning that it is less contractile than the uncompromised myocardial tissue. As this situation worsens, the local area of compromised myocardium may in fact bulge out as the heart contracts, further decreasing the heart's ability to move blood forward. When local wall motion moves in this way, it is said to be dyskinetic, or akinetic. The dyskinetic portion of the myocardium may stretch and eventually form an aneurysmic bulge. Certain diseases may cause a global dilated myopathy, i.e., a general enlargement of the heart when this situation continues for an extended period of time.
[0007] As the heart begins to fail, distilling pressures increase, which stretches the ventricular chamber prior to contraction and greatly increases the pressure in the heart. In response, the heart tissue reforms to accommodate the chronically increased filling pressures, further increasing the work that the now comprised myocardium must perform.
[0008] This vicious cycle of cardiac failure results in the symptoms of congestive heart failure, such as shortness of breath on exertion, edema in the periphery, nocturnal dypsnia (a characteristic shortness of breath that occurs at night after going to bed), waking, and fatigue, to name a few. The enlargements increase stress on the myocardium. The stress increase requires a larger amount of oxygen supply, which can result in exhaustion of the myocardium leading to reduced cardiac output of the heart.
SUMMARY OF THE INVENTION
[0009] The invention provides an apparatus for improving cardiac function comprising at least one external actuator, an elongate manipulator connected to the external actuator, a manipulator-side engagement component on a distal end of the elongate manipulator, a collapsible and expandable frame, a frame-side engagement component releasably engageable with the manipulator side-engagement component so that the external actuator can steer the frame when collapsed into a ventricle of a heart whereafter the frame is expanded, and at least one anchor connected to the frame, movement of the external actuator allowing for (i) insertion of the anchor and (ii) a myocardium ventricle, (iii) subsequent withdrawal of the anchor of the myocardium, (iv) subsequent reinsertion of the anchor into the myocardium, said insertion securing the frame to the myocardium in a selected position, and (v) subsequent disengagement of the manipulator-side engagement component from the frame-side engagement component, said disengagement for releasing the frame from the elongate manipulator.
[0010] The frame may have a small cross-dimension when collapsed suitable for being inserted into the ventricle of the heart through a tubular passage in a large cross-dimension when expanded in the ventricle.
[0011] The frame may comprise plurality of segments extending from a central portion of the frame.
[0012] The frame may be made of nickel titanium or stainless steel.
[0013] The apparatus may further comprise a membrane stretched between the segments, the membrane dividing the ventricle into at least two volumes. The membrane may be made of ePTFE. The membrane may be a mesh.
[0014] The segments may further comprise first and second portions connected at ends thereof such that the second portions are at an angle to the first portions.
[0015] The frame may have proximal and distal sections. The frame may have a diameter of between 10 mm and 100 mm when expanded.
[0016] The apparatus may further comprise at least one active anchor and at least one passive anchor. Said insertion of the passive anchor may be in a first direction and said withdrawal of the passive anchor may be in a second direction, the second direction being substantially 180 degrees from the first direction.
[0017] The apparatus may further comprise a first passive anchor extending in the first direction and a second passive anchor extending in a third direction. The active and passive anchors may have sharp ends that penetrate the myocardium.
[0018] The apparatus may further comprise a tubular passage with a distal end suitable to be inserted into the ventricle.
[0019] The elongate manipulator may further comprise a frame member with proximal and distal ends and an anchor member with proximal and distal ends, the frame and anchor members being moveable through the tubular passage.
[0020] The manipulator side-engagement component may further comprise a frame formation on the distal end of the frame member and an anchoring formation on the distal end of the anchor member.
[0021] The apparatus may further comprise an external frame actuator connected to the proximal end of the frame member and an external anchor actuator connected to the proximal end of the anchor member.
[0022] When the distal end of the elongate manipulator is in the selected position, a first movement of the external anchor actuator may cause the active anchor to be inserted into the myocardium to secure the frame to the myocardium and a second movement of the external anchor actuator may cause the active anchor to withdraw from the myocardium, said withdrawal releasing the frame from the myocardium.
[0023] A first movement of the external frame actuator may cause the frame formation to engage the frame-side engagement component, said engagement securing the frame to the distal end of the elongate manipulator and a second movement of the external frame actuator may cause the frame formation to disengage the frame-side engagement component, said disengagement releasing the frame from the elongate manipulator.
[0024] The frame may be shaped such that entry of the proximal section of the frame into the tubular passage causes the frame to partially collapse such that the passive anchor withdraws from the myocardium in the second direction and entry of the distal section of the frame into the tubular passage causes the frame to collapse to the small cross-section so that the distal end of the elongate manipulator and the frame can be removed from the heart.
[0025] The elongate manipulator and the frame may be insertable into the heart simultaneously and the frame may be shaped such that exposure of the distal section of the frame from the distal end of the tubular passage allows the frame to partially expand and exposure of the proximal section of the frame from the distal end of the tubular passage allows the frame to expand to a large cross-section, said expansion causing the passive anchors to penetrate the myocardium to secure the frame to the myocardium.
[0026] The invention also provides an apparatus for improving cardiac function comprising a frame which includes a plurality of central segments surrounding a central axis, the central segments having first and second ends, the first ends being pivotally connected to one another, and a plurality of outer segments having first and second ends, the first ends being pivotally secured to the second ends of the central segments, a membrane secured to the frame such that movement of the second ends of the central segments away from the central axis causes the membrane to unfold, the unfolding of the membrane causing the outer segments to pivot relative to the respective central segments away from the central axis and movement of the second ends of the central segments toward the central axis causes the membrane to fold, the folding of the membrane causing the outer segments to pivot relative to their respective central segments toward the central axis, and an anchor connected to the frame, the anchor being insertable into a myocardium of a heart to secure the cardiac device to the myocardium in a ventricle of the heart.
[0027] The frame may include at least three central segments and at least three outer segments.
[0028] The membrane may be stretched between the central and the outer segments.
[0029] The anchor may be secured directly to the frame.
[0030] The invention further provides an apparatus for improving cardiac function comprising a frame, a membrane, having an inner surface, secured to the frame, the membrane and the frame jointly forming a cardiac device being moveable between a collapsed and an expanded state, in a collapsed state at least a portion of the inner surface of the membrane facing a vertical axis of the cardiac device and the cardiac device being insertable into a ventricle of a heart, in the expanded state the portion of the inner surface of the membrane facing away from the vertical axis and being in contact with a myocardium and the cardiac device being in a selected position in the ventricle, and an anchor connected to the cardiac device, the anchor being insertable into the myocardium of the heart to secure the cardiac device to the myocardium in the selected position in the ventricle.
[0031] The cardiac device may collapse toward the vertical axis and expand away from the vertical axis.
[0032] The membrane may fold towards the vertical axis when the cardiac device collapses and may unfold away from the vertical axis when the cardiac device expands.
[0033] The frame may be at least one of nickel titanium and stainless steel.
[0034] The membrane may be made of ePTFE.
[0035] The anchor may have a sharp end.
[0036] The invention further provides an apparatus for improving cardiac function comprising a frame being expandable in a selected position to a pre-set shape in a ventricle of a heart, a formation on the frame, and an anchoring device having an anchor, the anchoring device being engaged with and rotatable relative the formation to rotate the anchor relative to the frame, said rotation causing the anchor to be inserted into a myocardium of the heart, said insertion securing the frame in the selected position in the ventricle.
[0037] The anchoring device may engage the formation such that a first rotation of the anchoring device causes the anchor to move away from the frame and a second rotation of the anchoring device causes the anchor to move toward the frame.
[0038] The formation may be a pin, and the anchor may be a screw.
[0039] The invention further provides an apparatus for improving cardiac function comprising at least a primary expandable frame being in a selected position in a ventricle of a heart when expanded, an anchor connected to the frame, the anchor being insertable into a myocardium of the heart to secure the primary frame within the ventricle, a frame-side engagement component connected to the primary frame, a membrane, and a membrane-side engagement component being engageable with the frame-side engagement component, said engagement securing the membrane to the frame.
[0040] The apparatus may further comprise a secondary expandable frame being in a selected position in the ventricle of the heart when expanded, the secondary frame being secured to the membrane and connected to the membrane-side engagement component thereby interconnecting the membrane to the membrane-side engagement component.
[0041] The anchor may be connected to the at least one frame.
[0042] The frame-side engagement component may be connected to the primary frame at a central portion of the primary frame.
[0043] The membrane-side engagement component may be connected to the secondary frame at a central portion of the secondary frame.
[0044] The apparatus may further comprise an active anchor being connected to the frame-side engagement component such that a first movement of the frame-side engagement component causes the active anchor to enter the myocardium and a second movement of the frame-side engagement component causes the active anchor to withdraw from the myocardium.
[0045] The apparatus may further comprise a passive anchor being connected to at least one of the frames such that the passive anchor enters the myocardium when the frame expands.
[0046] The invention further provides an apparatus for improving cardiac function comprising a flexible liner, a membrane secured to the liner, the membrane and the liner jointly forming a cardiac device being moveable between a collapsed and an expanded state, in the collapsed state the cardiac device being insertable into a ventricle of a heart. In the expanded state the cardiac device being in a selected position in the ventricle, the liner covering a wall in the ventricle and the membrane separating the ventricle into two volumes, and an anchor connected to the cardiac device, the anchor being insertable into a myocardium of the heart to secure the cardiac device to the myocardium in the selected position in the ventricle.
[0047] The flexible liner may comprise a plurality of lengths of strands being connected at endpoints thereof.
[0048] The apparatus may further comprise a frame secured to the cardiac device and connected to the anchor thereby interconnecting the cardiac device and the anchor.
[0049] The apparatus may further comprise a frame-side engagement component being connected to the cardiac device and an active anchor being connected to the frame-side engagement component such that a first movement of the frame-side engagement component causes the active anchor to enter the myocardium and a second movement of the frame-side engagement component causes the active anchor to withdraw from the myocardium.
[0050] The apparatus may further comprise a passive anchor being connected to the cardiac device such that the passive anchor enters the myocardium when the cardiac device expands.
[0051] The invention further provides an apparatus for improving cardiac function comprising an expandable frame being in a selected position in a ventricle of the heart and having an outer edge when expanded, the outer edge defining a non-planar cross-section of an inner wall of a ventricle and an anchor connected to the frame, the anchor being insertable into the myocardium of the heart to secure the frame to the myocardium in the selected position in the ventricle.
[0052] The apparatus may further comprise a membrane being secured to a frame, the membrane separating the ventricle into two volumes.
[0053] The frame may have a vertical axis and the outer edge may have a diameter, the diameter intersecting the vertical axis at an angle other than 90 degrees.
[0054] The invention further provides an apparatus for improving cardiac function comprising an anchor being insertable into a myocardium of a heart to secure the anchor to the myocardium within a ventricle of the heart, an anchor-side engagement component being secured to the anchor, an expandable frame being in a selected position in the ventricle when expanded, and a frame-side engagement component being secured to the frame, the frame-side engagement component being engageable with the anchor-side engagement component, said engagement securing the frame to the anchor in the selected position in the ventricle.
[0055] The apparatus may further comprise a membrane being secured to the frame.
[0056] A first movement of the anchor-side engagement component may cause the anchor to enter a myocardium and a second movement of the anchor-side engagement component may cause the anchor to withdraw from the myocardium.
[0057] A first movement of the frame-side engagement component may cause the frame-side engagement component to engage the anchor-side engagement component and a second movement of the frame-side engagement component may cause the frame-side engagement component to disengage the anchor-side engagement component.
[0058] Said engagement may release the frame from the anchor.
[0059] The invention further provides an apparatus for improving cardiac function comprising a flexible body, a membrane connected to the flexible body, the membrane and flexible body jointly forming a cardiac device being movable between a collapsed and an expanded state, in the collapsed state the cardiac device being insertable into a ventricle of the heart, in the expanded state the cardiac device being in a selected position in the ventricle, and an anchor connected to the cardiac device, the anchor being insertable into the myocardium of the heart to secure the cardiac device to the myocardium in the selected position of the ventricle.
[0060] The apparatus may further comprise a frame having a distal end, the membrane may be secured to the frame, and the body may have proximal and distal ends, the proximal end of the body being secured to the distal end of the frame, and the distal end of the body being connected to the anchor.
[0061] The body may be cylindrical with a diameter of between 0.5 mm and 6 mm and a height of between 1 mm and 100 mm.
[0062] The cardiac device may have a vertical axis.
[0063] The body may have a proximal opening at the proximal end, a distal opening at the distal end, and a passageway therethrough connecting the proximal and distal openings.
[0064] The body may be able to bend between 0 and 120 degrees from the vertical axis.
[0065] The invention further provides a device for improving cardiac function comprising a collapsible and expandable frame having first and second portions, the frame being insertable into a ventricle of a heart when collapsed, when expanded the frame being in a selected position in the ventricle and the second portion of the frame covering a wall in the ventricle, a membrane secured to the frame such that the membrane divides the ventricle into at least two volumes when the frame is expanded, the frame and the membrane jointly forming a cardiac device, and an anchor connected to the cardiac device, the anchor being insertable into a myocardium of the heart to secure the cardiac device in the selected position in the ventricle.
[0066] The frame may further comprise a plurality of segments, each segment having an inner and outer portion being connected at ends thereof, the outer portions being at an angle to the inner portions.
[0067] The membrane may be secured to the inner and outer portions of the segments.
[0068] The device may further comprise a plurality of anchors being connected to at least one segment such that when the frame expands the anchors enter the myocardium in a first direction, and when the frame collapses the anchors withdraw from the myocardium in a second direction approximately 180 degrees from the first direction.
[0069] Some of the anchors may extend in a third direction.
[0070] The invention further provides a system for improving cardiac function comprising a collapsible and expandable frame, when collapsed the frame being insertable into a selected position in a ventricle of the heart through an opening in the heart having a small cross-dimension, when expanded in the selected position, the frame having a large cross-dimension, and an anchor connected to the frame, being insertable into a myocardium of the heart to secure the frame to the myocardium in the selected position.
[0071] The opening may be an incision in the myocardium.
[0072] The anchor may further comprise a plurality of strands woven through the myocardium such that the opening is closed.
[0073] The invention further provides a system for improving cardiac function comprising an external actuator, an elongate manipulator having a tube suitable to be inserted into a ventricle of a heart to a selected position and a deployment member positioned therein slidable between a first and second position, the deployment member having proximal and distal ends, the distal end being within the tube when the deployment member is in the first position and out of the tube when the deployment member is in the second position, the deployment member being connected to the external actuator at the proximal end thereof, a deployment-side engagement component on the distal end of the deployment member, a frame-side engagement component being engageable with the deployment-side engagement component, said engagement securing the deployment-side engagement component to the frame-side engagement component such that a movement of the external actuator causes the engagement components to disengage, said disengagement releasing the deployment-side engagement component from the frame-side engagement component, a frame being connected to the frame-side engagement component, the frame being moveable between a collapsed and an expanded state, the frame being connected to the deployment member in the collapsed state with a small cross-dimension when the deployment member is in the first position and the frame is within the tube, the frame being shaped such that when the deployment member is moved to the second position and the frame exits the tube, the frame expands to the expanded state with a large cross-dimension and when the deployment member is moved back to the first position, the frame collapses to the collapsed state as the frame enters the tube, and an anchor connected to the frame being insertable into a myocardium of the heart to secure the frame to the myocardium of the heart, such that the deployment mechanism can be removed from the heart, the anchor entering the myocardium in a first direction when the frame expands and withdrawing from the myocardium in a second direction when the frame collapses, said withdrawal releasing the frame from the myocardium.
[0074] The external manipulator may further comprise an anchor deployment knob and a detachment knob.
[0075] The deployment member may further comprise an anchor shaft having proximal and distal ends and a detachment shaft having proximal and distal ends, the proximal end of the anchor shaft being connected to the anchor deployment knob, the proximal end of the detachment shaft being connected to the detachment knob.
[0076] The deployment-side engagement component may further comprise a deployment-side anchor formation connected to the distal end of the anchor shaft and a deployment-side detachment formation connected to the distal end of the detachment shaft.
[0077] The frame-side engagement component may further comprise a frame-side anchor formation being connected to the anchor and a frame-side detachment formation on the frame, the frame-side anchor formation being engageable with the deployment-side anchor formation, the frame-side detachment formation being engageable with the deployment-side detachment formation, a first movement of the detachment knob causing the deployment-side detachment formation to engage the frame-side detachment formation, said engagement securing the frame to the deployment member, a first movement of the anchor deployment knob causing the anchor to enter the myocardium and a second movement of the anchor deployment knob causing the anchor to withdraw from the myocardium, a second movement of the detachment knob causing the deployment-side detachment formation to disengage the frame-side detachment formation, said disengagement releasing the frame from the deployment member.
[0078] The anchor shaft and the detachment shaft may be coaxial.
[0079] The anchor shaft may be an inner torque shaft and the detachment shaft may be an outer torque shaft.
BRIEF DESCRIPTION OF THE DRAWINGS
[0080] The invention is further described by way of examples with reference to the accompanying drawings, wherein:
[0081] FIG. 1 is an exploded side view of a system for improving cardiac function, according to one embodiment of the invention, including a cardiac device and a deployment system, the deployment system including a deployment mechanism and a catheter tube;
[0082] FIG. 2 is a cross-sectional side view of a handle of the deployment mechanism and a proximal end of a deployment member of the deployment mechanism;
[0083] FIG. 3A is cross-sectional side view of a distal end of the deployment member including a key and a detachment screw;
[0084] FIG. 3B is a cross-sectional end view on 3 B- 3 B in FIG. 3A of the deployment member;
[0085] FIG. 3C is a cross-sectional end view on 3 C- 3 C in FIG. 3A of the key;
[0086] FIG. 4 is a perspective view of the cardiac device including a hub, a frame, and a stem thereof;
[0087] FIG. 5A is a side view of the cardiac device;
[0088] FIG. 5B is a perspective view of the hub;
[0089] FIG. 5C is a top plan view of the hub;
[0090] FIG. 6 is a cross-sectional side view of the stem;
[0091] FIG. 7A is a side view of the distal end of the deployment member connected to the cardiac device;
[0092] FIG. 7B is a cross-sectional view on 7 B- 7 B in FIG. 7A of the cardiac device;
[0093] FIG. 8 is a cross-sectional side view of the cardiac device with the key connected thereto;
[0094] FIG. 9 is a side view of the system of FIG. 1 with the components integrated with and connected to one another;
[0095] FIG. 10A is a view similar to FIG. 9 with the cardiac device partially retracted into the catheter;
[0096] FIG. 10B is a cross-sectional side view of a portion of FIG. 10A ;
[0097] FIG. 11A is a side view of the system with the cardiac device further retracted;
[0098] FIG. 11B is a cross-sectional side view of a portion of FIG. 11A ;
[0099] FIG. 12A is a side view of the system with the cardiac device fully retracted;
[0100] FIG. 12B is a cross-sectional side view of a portion of FIG. 12A ;
[0101] FIG. 13A is a cross-sectional side view of a human heart with the catheter inserted therein;
[0102] FIGS. 13B-13K are cross-sectional side views of the human heart illustrating installation ( FIGS. 13B-13E ), removal ( FIGS. 13E-13H ), and subsequent final installation ( FIGS. 13I-13K ) of the cardiac device;
[0103] FIG. 14A is a perspective view of a cardiac device according to another embodiment of the invention;
[0104] FIG. 14B is a cross-sectional side view of the human heart with the cardiac device of FIG. 14A installed;
[0105] FIG. 15A is a perspective view of a cardiac device according to a further embodiment on the invention;
[0106] FIG. 15B is a cross-sectional top plan view of the cardiac device on 15 B- 15 B in FIG. 15A ;
[0107] FIG. 15C is a cross-sectional side view of the human heart with the cardiac device of FIG. 15A installed;
[0108] FIG. 16A is a perspective view of a cardiac device according to a further embodiment of the invention;
[0109] FIG. 16B is a cross-sectional side view of the cardiac device of FIG. 16A ;
[0110] FIG. 16C is a cross-sectional side view of the human heart with the cardiac device of FIG. 16A installed;
[0111] FIG. 17A is a perspective view of a cardiac device according to a further embodiment of the invention;
[0112] FIG. 17B is a cross-sectional side view of the human heart with the cardiac device of FIG. 17A installed;
[0113] FIG. 18A is a perspective view of a cardiac device according to a further embodiment of the invention;
[0114] FIG. 18B is a cross-sectional side view of the human heart with the cardiac device of FIG. 18A installed;
[0115] FIG. 19A is a perspective view of a cardiac device according to a further embodiment of the invention;
[0116] FIG. 19B is a cross-sectional side view of the human heart while the cardiac device of FIG. 19A is being installed;
[0117] FIG. 19C is a cross-sectional side view of the human heart while the cardiac device of FIG. 19A is being installed;
[0118] FIG. 19D is a cross-sectional side view of a human heart with the cardiac device of FIG. 19A installed;
[0119] FIG. 20A is a perspective view of a frame of a cardiac device according to another embodiment of the invention;
[0120] FIG. 20B is a perspective view of a stem of the cardiac device of FIG. 20A ;
[0121] FIG. 20C is a cross-sectional side view of the cardiac device of FIG. 20A and FIG. 20B with the stem attached to the frame;
[0122] FIG. 20D is a cross-sectional side view of a distal end of a deployment member of a deployment mechanism according to another embodiment of the invention;
[0123] FIG. 20E is a cross-sectional side view of the distal end of the deployment member of a deployment mechanism of FIG. 20D ; and
[0124] FIGS. 20F-20I are cross sectional side views of a human heart illustrating installation of the cardiac device of FIG. 20A and FIG. 20B .
DETAILED DESCRIPTION OF THE INVENTION
[0125] FIG. 1 illustrates a system 30 for improving cardiac function according to one embodiment of the invention. The system 30 includes a deployment system 32 and a cardiac device 34 . The deployment system 32 includes a deployment mechanism 36 and a catheter tube 38 .
[0126] The catheter tube 38 is cylindrical with a length 40 of 110 cm and a diameter 42 of 5 mm. The catheter tube 38 has a circular cross-section and is made of a soft, flexible material.
[0127] The deployment mechanism 36 includes a handle 44 and a deployment member 46 . The handle 44 has a proximal end 48 and a distal end 50 . The deployment member 46 has a proximal end 52 and a distal end 54 . The proximal end 52 of the deployment member 46 is secured to the distal end 50 of the handle 44 .
[0128] FIGS. 2, 3A , 3 B, and 3 C illustrate the deployment mechanism 36 in more detail. FIG. 2 illustrates the handle 44 while FIGS. 3A, 3B , and 3 C illustrate components at the distal end 54 of the deployment member 46 . The components of the deployment mechanism 36 are primarily circular with center lines on a common axis.
[0129] The handle 44 is made of molded plastic and includes a main body 56 , an anchor knob 58 , an end piece 60 , a proximal rotating hemostatic valve 62 , a fluid line 64 , a distal rotating hemostatic valve 66 , and a detachment knob 68 . The main body 56 is cylindrical with a length 70 of 80 mm and a diameter 72 of 25 mm. The main body 56 has a proximal 74 and a distal 76 opening at the respective ends thereof and a passageway 78 therethrough connecting the openings with an inner diameter 80 of 4 mm.
[0130] The proximal rotating hemostatic valve 62 is a cylindrical body with a passageway 82 therethrough having an inner diameter 84 of 4 mm, a locking hypo tube 86 within the passageway, a tapered outer end 88 , and a raised formation 90 at a central portion thereof. The proximal rotating hemostatic valve 62 is rotationally secured to the proximal opening 74 of the handle 44 . The locking hypo tube 86 is a cylindrical body secured within the passageway 82 of the proximal rotating hemostatic valve 62 .
[0131] The end piece 60 is a cylindrical body with a passageway 92 therethrough connecting a proximal 94 and distal 96 opening at respective ends and having an inner diameter 98 of 5 mm. Raised formations 100 stand proud from respective central and outer portions of the end piece. A cylindrical end piece pin 102 is connected to an inner surface and extends across the inner diameter 98 of the passageway 92 . The end piece pin 102 is made of stainless steel and has a length of 5 mm and a diameter of 2 mm. The distal opening 96 of the end piece 60 mates with the tapered outer end 88 of the proximal rotating hemostatic valve 62 .
[0132] The anchor knob 58 is a cap-shaped body with a length 104 of 20 mm and an outer diameter 106 of 10 mm. The anchor knob 58 has a small opening 108 at a proximal end 110 with a diameter 112 of 4 mm and a large opening 114 at a distal end 116 with a diameter 118 of 6 mm. The anchor knob 58 fits over and is secured to both the end piece 60 and the proximal rotating hemostatic valve 62 .
[0133] The fluid line 64 enters the handle 44 through the small opening 108 of the anchor knob 58 and is secured to the proximal opening 94 of the end piece 60 . The fluid line 64 has an outer diameter 120 of 5 mm.
[0134] The distal rotating hemostatic valve 66 is a cylindrical body with a passageway 122 therethrough having a proximal inner diameter 124 of 4 mm at a proximal end 126 thereof and a distal inner diameter 128 of 5 mm at a distal end 130 thereof. The distal end 130 is tapered, and a raised formation 132 lies at a central portion thereof. The distal rotating hemostatic valve 66 is rotationally secured to the distal opening 76 of the main body 56 .
[0135] The detachment knob 68 is a cap-shaped body with a length 134 of 20 mm and an outer diameter 136 of 20 mm. The detachment knob 68 has a large opening 138 at a proximal end 140 with a diameter 142 of 8 mm and a small opening 144 at a distal end 146 with a diameter 148 of 5 mm. The detachment knob 68 fits over and is secured to the distal rotating hemostatic valve 66 .
[0136] Referring to FIGS. 3A-3C , the deployment member 46 includes an inner torque shaft 150 and an outer torque shaft 152 . The inner torque shaft has a diameter 154 of 2 mm and is made of surgical stainless steel. The outer torque shaft is a hollow, cylindrical body with an inner diameter 156 of 3 mm and an outer diameter 158 of 5 mm. The outer torque shaft 152 is a polymer.
[0137] Referring again to FIG. 2 , the inner torque shaft 150 passes through the detachment knob 68 , through the distal rotating hemostatic valve 66 , into and out of the passageway 78 of the main body 56 , through the proximal rotating hemostatic valve 62 , and into the end piece 60 . The proximal end of the inner torque shaft 150 is wrapped around the end piece pin 102 , reenters the proximal rotating hemostatic valve 62 , and is attached to the locking hypo tube 86 within the proximal rotating hemostatic valve 62 .
[0138] The outer torque shaft 152 is coaxial with and surrounds the inner torque shaft 150 . A proximal end 160 of the outer torque shaft 152 passes into the distal hemostatic valve 66 and is secured thereto.
[0139] The distal end 54 of the deployment member 46 includes a key 162 , a detachment screw 164 , and a securing mechanism 166 . A distal end 168 of the inner torque shaft 150 extends out of a distal end 170 of the outer torque shaft 152 , and the key 162 is attached thereto. The key 162 is rectangular with a length 171 of 7 mm and a height 172 of 3 mm. The key 162 has a semi-circular cross section with a radius 174 of 1.5 mm. The detachment screw 164 is attached to the distal end 170 of the outer torque shaft 152 , extends to a length 176 of 7 mm, and has a diameter 178 of 5 mm.
[0140] The securing mechanism 166 includes an inner component 180 and an outer component 182 . The inner component 180 is a raised cylindrical portion coaxial with and on the inner torque shaft 150 . The inner component 180 stands proud of the inner toque shaft 150 by 0.5 mm. The outer component 182 is a hollow, cylindrical body secured to an inner surface of the outer torque shaft 152 and has proximal and distal openings with diameters of 2.25 mm so that the inner toque shaft 150 cannot move axially relative to the outer torque shaft 152 .
[0141] FIGS. 4 , 5 A- 5 C, and 6 illustrate the cardiac device 34 in more detail. The cardiac device 34 includes a frame 184 and a stem 186 , or flexible body, and has a vertical axis 188 .
[0142] The frame 184 includes a frame hub 190 , a plurality of main segments 192 , and a membrane 194 . The hub 190 is a ring-shaped body with an outer surface 196 with a diameter 198 of 5 mm, an inner surface 200 with a diameter 202 of 4 mm, a thickness 204 of 3 mm, and a pin 206 extending off-center across the inner surface 200 creating a smaller and a larger gap. The pin 206 has a length of 3.5 mm and a diameter of 1 mm and is located in a plane 208 . The frame 184 has a diameter 209 of approximately 25 mm, however, other embodiments may have diameters of between 10 mm and 100 mm. The entire hub 190 is made of nickel titanium.
[0143] The main segments 192 include first portions, or central segments, 210 , second portions, or outer segments, 212 , and passive anchors 214 . The first portions 210 are connected to the hub 190 at a central portion of the outer surface 196 and extend radially from the hub 190 at an angle away from the plane 208 of the pin 206 to a length 216 of 8 mm. The second portions 212 of the segments 192 are connected to ends of the first portions 210 and further extend radially from the hub 190 but at an angle towards the plane 208 . The second portions 212 each have a length 218 of 5 mm. The passive anchors 214 are formed at an end of each of the second portions 212 . The passive anchors 214 have sharp ends that point slightly radially from the hub 190 . The segments 192 are made from nickel titanium, which after a prescribed thermal process, allows for the segments 192 to hold their shape as illustrated, for example, in FIG. 4 . The entire frame 184 , or just portions of the frame 184 , may also be made of stainless steel.
[0144] The membrane 194 is stretched over the first 210 and second 212 portions of the segments 192 to give the frame 184 a disk like shape. The membrane 194 is made of expanded Poly Tetra Fuoro Ethylene (ePTFE) and has a thickness of 0.08 mm. Other embodiments may use a mesh membrane.
[0145] FIG. 6 illustrates the stem 186 unattached to the frame 184 . The stem 186 is a hollow, cylindrical body with a passageway 220 therethough connecting a proximal 222 and a distal 224 opening. The stem 186 has a height 226 of 9 mm, an outer diameter 228 of 5 mm, and an inner diameter 230 of 4 mm. The stem 186 includes a first hub 232 and a second hub 234 , both similar to the hub 190 on the frame 184 . The second hub 234 is secured within the passageway 220 near the distal opening 224 of the stem 186 . The first hub 232 is loose within the stem 186 so that it may move, and has an active anchor 236 , in the shape of a screw, attached. The active anchor 236 spirals from the first hub 232 to engage with the pin on the second hub 234 . The active anchor 236 has a diameter 238 of 3.5 mm and a length 240 of 7 mm.
[0146] The stem 186 is made of Poly Tetra Fuoro Ethylene (PTFE) and is thus expandable and flexible. Referring again to FIG. 4 , the stem 186 can be compressed or stretched by 30% of its length and can be bent from the vertical axis 188 of the device 34 by 120 degrees in any direction. The first hub 232 , second hub 234 , and active anchor 236 are made of nickel titanium. In other embodiments, the hubs may be made of stainless steel.
[0147] FIGS. 7A, 7B , 8 , and 9 illustrate the system 30 with the stem 186 connected to the cardiac device 34 and the cardiac device 34 connected to the deployment mechanism 36 . The stem 186 is fused to the frame hub 190 thus securing the stem 186 to the device 34 .
[0148] In use, the deployment member 46 is inserted through the catheter tube 38 so that the distal end 54 of the deployment member 46 exits the distal end of the tube 38 . As shown is FIGS. 7A and 7B , the deployment member 46 connects to the cardiac device 34 such that the key 162 engages the hub 190 of the frame 184 by passing through the larger gap in the hub 190 . As shown in FIG. 8 , the key 162 passes through the hub 190 of the frame 184 to engage with the first hub 232 of the stem 186 , but does not reach the second hub 234 . Once the key 162 is fully inserted into the stem 186 , the detachment knob 68 is turned which rotates the outer torque shaft 152 and thus the detachment screw 164 because the detachment screw 164 is attached to the outer torque shaft 152 . The rotation thereof causes the detachment screw 164 to engage with the pin 206 of the frame hub 190 , securing the cardiac device 34 to the deployment mechanism 36 .
[0149] Rotation of the anchor knob 58 in a first direction causes the active anchor 236 to be deployed from the distal opening 224 of the stem 186 because the anchor knob 58 is connected to the inner torque shaft 150 which, in turn, is connected to the key 162 . Rotation of the key 162 causes the first hub 232 to rotate and because the active anchor 236 is connected to the first hub 232 and engaged with the pin of the second hub 234 , the active anchor 236 “twists” out of the distal opening 224 of the stem while the first hub 232 is pulled toward the distal opening 224 . Rotation of the anchor knob 58 in a second direction causes the active anchor 236 to reenter the distal opening 224 of the stem 186 .
[0150] As illustrated in FIGS. 10A and 10B , the distal end 54 of the deployment member 46 is then pulled into the distal end of the catheter tube 38 . As a proximal section of the frame 184 enters the catheter tube 38 , the first portions 210 of the segments 192 begin to collapse towards the stem 186 . The segments 192 collapse, or fold, against a spring force that is created by the resilient nature of the nickel titanium material from which they are made. At the same time, the second portions 212 fan out radially away from the hub 190 .
[0151] As illustrated in FIGS. 11A and 11B , by the time a distal section of the frame 184 and the second portions 212 of the segments 192 begin to enter the tube 38 , the second portions 212 have been bent back to collapse towards the stem 186 similarly to the first portions 210 .
[0152] FIGS. 12A and 12B illustrate the system 30 with the cardiac device 34 completely contained within the catheter tube 38 .
[0153] FIGS. 13A-13J illustrate a human heart 242 while the cardiac device 34 is being deployed. The heart 242 contains a right ventricle 244 and a left ventricle 246 with papillary muscles 248 and an akinetic portion 250 with an apex 252 . The distal end of the catheter 38 has been inserted through the aorta and aortic valve into the left ventricle 246 to a selected position where the cardiac device 34 can be deployed. The catheter tube 38 is then partially pulled off of the cardiac device 34 exposing the stem 186 .
[0154] The active anchor 236 is then deployed by rotating the anchor knob 58 in a first direction. The active anchor 236 penetrates the myocardium of the heart 242 to secure the cardiac device 34 in the selected position at the apex 252 of the akinetic portion 250 of the left ventricle 246 .
[0155] The catheter 38 is then completely removed from the distal end 54 of the deployment member 46 , exposing the cardiac device 34 . As the cardiac device 34 expands, due to the resilient nature of the segments 192 and the pre-set shape of the frame 184 , the passive anchors 214 on the segments 192 penetrate the myocardium in a first direction. The membrane 194 seals a portion of the ventricle 246 and separates the ventricle 246 into two volumes.
[0156] If the cardiac device 34 has not been properly positioned, or if it is of the wrong size or shape for the particular heart, the device 34 may be repositioned or completely removed from the heart 242 .
[0157] Rotation of the anchor knob 58 in a second direction will cause the active anchor 236 to be removed from the apex 252 of the akinetic portion 250 of the left ventricle 246 thus releasing the cardiac device 34 from the heart 242 . The distal end 54 of the deployment member 46 may be retracted into the catheter 38 to once again fold the cardiac device 34 into the position shown in FIG. 12B , from where it can again be deployed. The passive anchors 214 are removed from the myocardium in a second direction which is approximately 180 degrees from the first direction so that minimal damage is done to the myocardium.
[0158] However, if the cardiac device 34 has been properly positioned and is of the proper size and shape, rotation of the detachment knob 68 in a second direction will cause the detachment screw 164 at the distal end 170 of the outer torque shaft 152 to disengage the pin 206 in the frame hub 190 , thus releasing the deployment member 46 from the cardiac device 34 to allow removal of the deployment member 46 from the heart 242 . FIG. 13K illustrates the heart 242 with the cardiac device 34 installed and the deployment mechanism 36 removed from the heart 242 .
[0159] One advantage of this system is that the shape of the frame 184 allows the device 34 to be retrieved as long as the deployment member 46 is still connected to the device 34 . When the device 34 is retrieved, the passive anchors 214 withdraw from the myocardium in a direction that is approximately 180 degrees from, or opposite, the first direction to minimize the amount of damage done to the myocardium. The device 34 also provides support for the akinetic region 250 , minimizes the bulging of the akinetic region 250 , and reduces stress on the working parts of the myocardium. A further advantage is that the ePTFE membrane 194 is biocompatible, has a non-thrombogenic surface, promotes healing, and accelerates endothelization.
[0160] FIG. 14A illustrates a cardiac device 254 according to another embodiment of the invention. The cardiac device includes a hub 256 , a frame 258 , and a membrane 260 . The hub 256 lies at a central portion of the frame 258 and an active anchor 262 is connected to the hub 256 and extends downwards therefrom. The frame 258 includes a plurality of segments 264 which extend radially and upwardly from the hub 256 . A sharp passive anchor 266 lies at the end of each of the segments 264 . The membrane 260 is stretched between the segments 264 to form a cone-shaped body.
[0161] FIG. 14B illustrates a human heart with the cardiac device 254 of FIG. 14A having been secured to an akinetic portion thereof.
[0162] FIG. 15A and FIG. 15B illustrate a cardiac device 268 according to a further embodiment of the invention. The cardiac device includes a hub 270 , a frame 272 , and membrane 274 . The hub 270 lies at a central portion of the frame 272 and an active anchor 276 extends downwardly from the hub 270 . The frame 272 includes a plurality of segments 278 which extend radially and upwardly from the hub 270 . The segments 278 are of different lengths such that an outer edge 280 of the cardiac device 268 is not planar. The device 268 has a vertical axis 282 which intersects a diameter 284 across the outer edge 280 of the device 268 at an angle other than 90 degrees. A sharp passive anchor 286 lies at the end of each of the segments 278 . The membrane 274 is stretched between the segments 278 to form a cone-shaped body. Referring specifically to FIG. 15B , a cross-section perpendicular to the vertical axis 282 of the device 268 is circular.
[0163] FIG. 15C illustrates a human heart with the cardiac device 268 of FIG. 15A having been secured to an akinetic portion thereof. The outer edge 280 of the cardiac device 268 defines a non-planar cross-section of an inner surface of the left ventricle.
[0164] A further advantage of this embodiment is that the device 268 can be sized and shaped for use on a wider variety of akinetic portions in left ventricles.
[0165] FIG. 16A and FIG. 16B illustrate a cardiac device 288 according to a further embodiment of the invention. The cardiac device 288 includes a first hub 290 , a first frame 292 , a second hub 294 , a second frame 296 , a first membrane 298 , and a second membrane 300 . The first hub 290 is attached to a central portion of the first frame 292 . A plurality of segments 302 extend radially from and upwards from the first hub 290 . The first membrane 298 is occlusive and made of a thrombogenic material and stretched between the segments 302 to form a first cone-shaped body. A plurality of fibers 304 extend radially from an outer edge 306 of the first cone-shaped body. An active anchor 308 extends down from the first hub 290 .
[0166] The second frame 296 includes a plurality of segments 310 extending radially and upwardly from the second hub 294 and end in sharp passive anchors 312 . An attachment screw 314 , similar to the detachment screw 164 , extends downwards from the second hub 294 . Referring specifically to FIG. 16B , the attachment screw 314 is rotated so that it engages a pin 316 within the first hub 290 , similarly to the frame hub 190 already described, to secure the second frame 296 to the first frame 292 . The second membrane 300 is made of ePTFE and stretched between the segments 310 to form a second cone-shaped body.
[0167] FIG. 16C illustrates a human heart with the cardiac device 288 of FIG. 16A secured to an akinetic portion thereof. The fibers 304 on the outer edge 306 of the first frame 292 are interacting with an inner surface of the left ventricle to seal off the volume below the outer edge 306 of the first frame 292 . The passive anchors 312 on the ends of the segments 310 of the second frame 296 have penetrated the myocardium to hold the device 288 in place.
[0168] A further advantage of this embodiment is that the fibers 304 of the first membrane 298 interface with trabeculae and further block the flow of blood into the apex of the akinetic portion.
[0169] FIG. 17A illustrates a cardiac device 318 according to a further embodiment of the invention. The cardiac device 318 includes proximal 320 and distal 322 hubs, a frame 324 , a stem 326 , a braided structure 328 , and a membrane 330 . The frame 324 includes a plurality of segments 332 extending radially and upwards from the distal hub 322 , and the membrane 330 is stretched between the segments 332 to form a cone-like body having an outer edge 334 . Two extra segments 336 extend across the outer edge 334 of the cone-like body and are connected to and support the proximal hub 320 above the distal hub 322 . The stem 326 , including an active anchor 338 , extends downwards from the distal hub 322 . The braided structure 328 is made of nickel titanium and is connected to a distal end of the stem 326 into the ends of the segments 332 . The segments 332 end in sharp passive anchors 340 . The braided structure 328 may also be made of a biodegradable material or a polymer.
[0170] FIG. 17B illustrates a human heart with the cardiac device 318 of FIG. 17A having been secured to an akinetic portion thereof. The braided structure 328 presses against an inner surface of the left ventricle.
[0171] A further advantage of this embodiment is that the braided structure 328 allows the device to “nestle” into position before the active anchor 338 is deployed to secure the device 318 in place. Further advantages are that the braided structure 328 adds structural stability to the device 318 and the nickel titanium of the braided structure 328 provides a mechanism for containing thrombi in the static chamber.
[0172] FIG. 18A illustrates a cardiac device 342 according to a further embodiment of the invention. The cardiac device 342 includes proximal 344 and distal 346 hubs, a frame 348 , and a membrane 350 . A plurality segments 352 , having first 354 and second 356 portions, extend upwardly and radially from the distal hub 346 in a curved fashion and are bent and extend inwards to meet at the proximal hub 344 . The membrane 350 is stretched across the segments 352 to form a semi-circular or basket-shaped body. Sharp passive anchors 358 extend from the segments 352 between the first 354 and second 356 portions.
[0173] Some of the passive anchors 358 extend in a primarily axial direction with a small radial component, and some of the passive anchors 358 extend in a primarily radial direction with a small axial component. Other embodiments may have both types of passive anchors on a single segment.
[0174] FIG. 18B illustrates a human heart with the cardiac device 342 of FIG. 18A having been installed into an akinetic portion thereof. The segments 352 are pressed against the myocardium because the device is slightly oversized.
[0175] A further advantage of this embodiment is that because of the size of the device 342 and shape of the segments 352 , the passive anchors 358 are assisted in penetrating the myocardium. A further advantage is that because of the shape of the frame 348 , the device 342 can be retrieved from the left ventricle as long as the device 34 is still attached to the deployment member 46 . A further advantage is that because the entire frame 348 is covered with the membrane 350 , the flow of blood to the apex of the akinetic portion is even further blocked.
[0176] FIG. 19A illustrates a cardiac device 360 according to a further embodiment of the invention. The cardiac device 360 includes a frame 362 and a stem 364 . The frame 362 includes a plurality of segments 366 which extend upwardly and radially from the stem 364 and end in a plurality of sharp passive anchors 368 . The stem 364 extends downwards from the frame 362 and includes two suture strands 370 at a distal end thereof.
[0177] FIGS. 19B, 19C , and 19 D illustrate the installation of the cardiac device 360 of FIG. 16 . While a high pressure is maintained in the left ventricle the catheter tube 38 is inserted through the outer wall into the left ventricle with the cardiac device 360 inserted in the distal end thereof. The catheter 38 is removed from the cardiac device 360 , and the cardiac device 360 expands such that the passive anchors 368 are inserted into the inner surface of the left ventricle. The catheter 38 is then completely removed and the sutures 370 are used to close the insertion made by the catheter 38 and to secure the cardiac device 360 to the akinetic portion.
[0178] FIGS. 20A, 20B , and 20 C illustrate a cardiac device 372 according to a further embodiment of the invention. The cardiac device 372 includes a frame hub 374 , a frame 376 , a membrane 378 , and a stem 380 . The frame hub 374 lies at a central portion of the frame 376 . The frame 376 includes a plurality of segments 382 which extend radially and upwardly from the frame hub 374 . A sharp passive anchor 384 lies at the end of each of the segments 382 . The membrane 378 is stretched between the segments 382 to form a cone-shaped body. Before installation, the stem 380 is unattached to the frame hub 374 and includes a proximal hub 386 , an anchor hub 388 , and a distal hub 390 , each having a pin 392 extending across an inner surface thereof, similar to that of the frame hub 190 . The proximal 386 and distal 390 hubs are frictionally held near their respective ends in the stem 380 , and the anchor hub 388 is loose within the stem 380 so that it may move. An active anchor 394 extends downwards from the anchor hub 388 .
[0179] FIGS. 20D and 20E illustrate another embodiment of a distal end 396 of a deployment member 398 . The distal end 396 includes a detachment piece 400 and an attachment hub 402 . The detachment piece 400 has been added to the distal end of the outer torque shaft 152 . The detachment piece 400 is a ring shaped body made of stainless steel with a length of 3 mm and an inner diameter suitable to frictionally hold the attachment hub 402 , which is similar to the frame hub 190 . An attachment screw 404 , similar to the detachment screw 164 , extends downwards from the attachment hub 402 . Referring specifically to FIG. 20E , forces along the length of the deployment member 398 will, by design, cause the attachment hub 402 to become dislodged from the detachment piece 400 .
[0180] FIGS. 20F-20H illustrate installation of the cardiac device 372 of FIGS. 20A and 20B into a human heart. In this embodiment, the deployment member used does not include the securing mechanism 166 so that the inner and outer torque shafts may move axially relative to one another.
[0181] Before the device 372 and stem 380 are inserted into a heart, the inner torque shaft is passed through the frame hub 374 , the proximal hub 386 , and the anchor hub 388 , and the outer torque shaft is positioned and rotated so that the attachment screw 404 engages both the pins 392 of the frame 374 and proximal 386 hubs, securing the cardiac device 372 to the stem 380 . The device 372 and the stem 380 are then retracted into the catheter 38 and steered into a left ventricle. The stem 380 is secured to an apex of an akinetic portion of a left ventricle of the heart by rotating the inner torque shaft, causing the active anchor 394 to penetrate the myocardium. Rotation of the outer torque shaft then causes the attachment screw 404 to disengage the pin 392 of the proximal hub 386 , and the device 372 is released from the stem 380 . However, the inner torque shaft remains engaged with the hubs in the stem 380 .
[0182] If it is determined that the stem 380 has been properly positioned, the cardiac device 372 , secured to the outer torque shaft, is pushed over the inner torque shaft to meet the stem 380 . The outer torque shaft is again rotated so that the attachment screw 404 reengages the pin 392 on the proximal hub 386 of the stem, thus re-securing the stem 380 to the frame 376 . The deployment member 398 is then forcibly pulled away from the device 372 and the detachment piece 400 releases the attachment screw 404 . FIG. 201 illustrates the human heart with the cardiac device 372 of FIGS. 20A and 20B installed.
[0183] While certain exemplary embodiments have been described and shown in the accompanying drawings, it is to be understood that such embodiments are merely illustrative and not restrictive of the current invention, and that this invention is not restricted to the specific constructions and arrangements shown and described since modifications may occur to those ordinarily skilled in the art. | A system for improving cardiac function is provided. A foldable and expandable frame having at least one anchoring formation is attached to an elongate manipulator and placed in a catheter tube while folded. The tube is inserted into a left ventricle of a heart where the frame is ejected from the tube and expands in the left ventricle. Movements of the elongate manipulator cause the anchor to penetrate the heart muscle and the elongate manipulator to release the frame. The installed frame minimizes the effects of an akinetic portion of the heart forming an aneurysmic bulge. | 0 |
This is a divisional of U.S. patent application Ser. No. 08/923,116 filed on Sep. 4, 1997 U.S. Pat. No. 6,018,379, which is a divisional of U.S. patent application Ser. No. 08/661,898 filed on Jun. 12, 1996 U.S. Pat. No. 5,724,111. The subject matter of both applications is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a reflective liquid crystal display.
2. Description of Related Art
A reflective liquid crystal display does not require a backlight as a light source, since it is so configured that an external incident light is reflected by a reflector plate provided in an inside of the liquid crystal display, and the reflected light is utilized as a light source for display. This has been considered to be an effective means capable of reducing a consumed electric power, of thinning the display and of lightening the display, as compared with a transparent type liquid crystal display. A reflective liquid crystal commercially available at present is of a direct matrix drive STN (super twisted nematic) type.
However, the STN type reflective liquid crystal display does not have a satisfactory display characteristics in connection with a brightness and a resolution. Therefore, there has been considered an active matrix type configured to drive, by means of switching means such as thin film transistors or diodes, a liquid crystal of a TN (twisted nematic) type, a GH (guest-host) type, or a PDLC (polymer dispersed liquid crystal) type. In all these conventional reflective liquid crystal displays, a reflector is provided on an insulative plate located at a side opposite to an eye viewing side, and a transparent electrode is provided on an insulative plate at the eye viewing side. In addition, a convex-concave is formed at a reflecting surface of the reflector. With formation of the convex-concave reflecting surface, a light injecting onto the reflector is scattered, so that it is possible to prevent a face of a user and a background of the user from being reflected in a screen surface of the liquid crystal display.
Furthermore, the display performance greatly varies dependently upon the position of the reflector. In the STN type and the TN type which require a polarizer, since a polarizer has to be adhered on an outside surface of each of two insulative plates, the reflector is provided on an outside of the polarizer. As a result, a separation on the order of 0.2 mm to 1.1 mm corresponding to the thickness of the insulative plate, inevitably occurs between the reflector and an image displayed by the liquid crystal, so that a double image occurs, and therefore, when characters are displayed, a fuzziness of the displayed characters occurs. On the other hand, in the GH type and the PDLC type which require no polarize, since the reflector is provided in an inside of the two insulative plates, it is possible to prevent the double image.
Referring to FIG. 1, there is shown a diagrammatic sectional view of a conventional GH type reflective liquid crystal display having the above mentioned structure.
As shown in FIG. 1, on a lower insulative plate 1 , a switching device for an active matrix drive is formed, which is for example a thin film transistor (TFT) composed of a pair of source/drain electrodes 3 formed on the insulative plate 1 , a doped layer 4 formed on an inner side of each of the source/drain electrodes 3 , a semiconductor layer 5 formed on the insulative plate 1 between the pair of source/drain electrodes 3 and on each of doped layer 4 , a gate insulator film 6 formed on the semiconductor layer 5 , and a gate electrode 7 formed on the gate insulator film 6 .
Furthermore, a polyimide insulator film 15 is formed to cover the switching device as mentioned above and to cover the remaining portion of the lower insulative plate 1 . This insulator film 15 has an convex-concave surface, in a region other than the switching device, and a pixel electrode 8 is formed on the convex-concave surface of the insulator film 15 , and therefore, the pixel electrode 8 has a convex-concave surface corresponding to the convex-concave surface of the insulator film 15 . The pixel electrode 8 is connected to one source/drain electrode 3 of the switching device through a contact hole 6 formed in the insulator film 15 .
With the above mentioned structure, the pixel electrode 8 functions as a reflector having a convex-concave reflecting surface.
On an upper insulative plate 2 , a common electrode 9 which is a transparent electrode, is formed, and a liquid crystal material layer 10 is sandwiched between the lower insulative plate 1 and the upper insulative plate 2 . An image is viewed from a side of the upper insulative plate 2 .
The convex-concave of the insulative film 15 is formed by a conventional photolithography or an exposure-and-etching process using a photosensitive insulative material. This technology is disclosed by for example, (1) Japanese Patent Publication No. JP-B-61-6390, (2) Tohru KOIZUMI and Tatsuo UCHIDA, “Reflective Multicolor LCD (II): Improvement in the Brightness”, Proceedings of the SID, Vol. 29/2, pp.157-160, 1988, (3) S. Mitsui et al, “23.6: Late-News Paper: Bright Reflective Multicolor LCDs Addressed by a-Si TFTs”, SID 92 DIGEST, pp.437-440, 1992, and (4) Naofumi KIMURA et al, “Development of Reflective Multicolor LCD”, Sharp Technical Report, No. 56, pp.27-30. June 1993. The disclosure of these publications is incorporated by reference in their entirety into this application.
As mentioned above, the conventional reflective liquid crystal display has been configured to form a convex-concave at the reflecting surface of the reflector, in order to scatter the incident light, thereby to prevent a user's face and its background from being reflected in the display screen of the liquid crystal display. However, in the case of forming a convex-concave on a plate on which an active device such as a TFT device or an MIM device is formed, it is necessary to deposit an insulating film covering the active device and to pattern the deposited insulating film so as to form a convex-concave surface. But, in the patterning process for forming the convex-concave surface, a fine control of a shape such as an inclined angle of the convex-concave is difficult, with the result that a sufficient light scattering cannot be obtained.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a reflective liquid crystal display which has overcome the above mentioned defect of the conventional one.
Another object of the present invention is to provide a reflective liquid crystal display having a desired light scattering characteristics, and therefore, a high image quality and a high brightness, with neither a fuzziness of displayed characters nor a double image.
The above and other objects of the present invention are achieved in accordance with the present invention by a reflective liquid crystal display comprising a first insulative plate having a reflector and a second insulative plate having a transparent electrode, the first and second insulative plates being assembled in such a manner that the reflector opposes to the transparent electrode, separately from each other, and a liquid crystal layer sandwiched between the reflector and the transparent electrode, wherein the reflector has a planar reflecting surface, and a transparent electrode side surface of the second insulative plate has a convex-concave or a coating formed thereon having a light scattering property.
Alternatively, the second insulative plate has a thickness of not greater than 0.7 mm, and a surface of the second insulative plate opposite to the transparent electrode side surface of the second insulative plate, has has a convex-concave or a sheet adhered thereon having a light scattering property.
In a modification, the reflecting surface of the reflector may have a convex-concave.
The convex-concave surface of the second insulative plate giving the light scattering property, can be formed, for example, by abrading or grinding the surface of the second insulative plate with abrasive powder, and further etching it with a hydrofluoric acid if necessary. On the other hand, the light scattering coating can be formed by a spin-coating. The light scattering sheet can be adhered to the insulative plate after the two insulative plates are assembled and a liquid crystal material is injected into a space formed between the two insulative plates. If the insulative plate mixed with particles having a refractive index different from that of the plate material, is used, the display can be completed only by assembling the two insulative plates and injecting the liquid crystal between the two insulative plates, without adhering the light scattering sheet.
As seen from the above, by scattering the light at the side of the insulative plate having the transparent electrode, the scattering property can be given with only a very simple process which needs no patterning, and further, the scattering property itself can be easily controlled. Accordingly, an easily visible paper-white image can be obtained.
In the reflective liquid crystal display formed as mentioned above, the surface of the reflector is a mirror surface, but the opposing plate having the transparent electrode, has the convex-concave surface, or the coating or the sheet having the light scattering property, or is formed of a plate mixed with particles having a different refeactive index so as to scattering the light by action of a difference in the refractive index. In addition, since a light scattering causing portion is in contact with the transparent electrode for the liquid crystal material layer which produces an display image, or since the light scattering causing portion is formed on the transparent electrode through the intermediate of an extremely thin plate having a thickness of not greater than 0.7 mm, no fuzziness of the display image occurs. If the light scattering causing portion were formed on the transparent electrode through the intermediary of a plate having a thickness of not less than 1 mm, fuzziness of the displayed image becomes remarkable, and a recognition speed of legibility of a display character drops. Namely, the image quality is deteriorated.
Referring to FIG. 2, there is shown a graph illustrating a relation between a character reading time and a thickness of the opposing plate (between the light scattering causing portion and the transparent electrode). Since the reading time is different from one tester person to another, the reading time is standardized to “1” when the thickness of the opposing plate was 0.3 mm. In the reading test, Japanese “Kanji” characters “” and “”, which are similar to each other in appearance, were displayed, and a time was measured until each tester person answered what is the displayed character.
It could be noted from FIG. 2 that, if the thickness of the opposing plate exceeds 0.7 mm, the reading time, namely, the recognition time abruptly increases. In the case of scattering the light at the surface of the liquid crystal display, accordingly, it is important that the thickness of the opposing plate is maintained to be not greater than 0.7 mm.
Here, if the light scattering is made large at a side of the insulative plate having the transparent electrode, a backscattering becomes correspondingly large, and therefore, a brightness of a black display elevates, so that a contrast drops. However, this drop of contrast can be effectively suppressed by giving the light scattering property at a side of the insulative plate having the reflector, so that a reflective liquid crystal display having a sufficient light scattering property without dropping the contrast, can be obtained. In this case, even if the reflector were formed to have a convex-concave reflecting surface, a fine control of the shape of the convex-concave is not required, because the required light scattering property is given at the side of the insulating plate having the transparent electrode.
The above and other objects, features and advantages of the present invention will be apparent from the following description of preferred embodiments of the invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic sectional view of a conventional GH type reflective liquid crystal display;
FIG. 2 is a graph illustrating a relation between a thickness of the opposing plate and a character reading time; and
FIGS. 3 to 14 are diagrammatic sectional views of first to twelfth embodiments of the reflective liquid crystal display in accordance with the present invention, respectively.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 3 to 14 illustrate first to twelfth embodiments of the reflective liquid crystal display in accordance with the present invention, respectively.
Elements common to the first to twelfth embodiments of the reflective liquid crystal display are given the same Reference Numerals, and will be first described in the following.
As shown in FIGS. 3 to 14 , on a lower insulative plate 1 , there are formed a switching device for an active matrix drive and a pixel electrode 8 connected to the switching device. The shown switching device is a thin fill transistor (TFT) composed of a pair of source/drain electrodes 3 formed separately from each other on the insulative plate 1 , a doped layer 4 formed on an inner side of each of the source/drain electrodes 3 , a semiconductor layer 5 formed to cover the insulative plate 1 between the pair of source/drain electrodes 3 and each of the doped layer 4 , a gate insulator film 6 formed on the semiconductor layer 5 , and a gate electrode 7 formed on the gate insulator film 6 .
On the other hand, the pixel electrode 8 is formed to cover the insulative plate 1 and a portion of one source/drain electrode 3 of the switching device so that the pixel electrode 8 is electrically connected to the one source/drain electrode 3 . The pixel electrode 8 functions as a reflector.
On an upper insulative plate 2 , a common electrode 9 which is a transparent electrode, is formed. The lower insulative plate 1 and the upper insulative plate 2 are assembled separated from each other in such a manner that the pixel electrode 8 opposes to the common electrode 9 , and a liquid crystal material layer 10 is sandwiched between the lower insulative plate 1 and the upper insulative plate 2 . An image is viewed from a side of the upper insulative plate 2 .
EMBODIMENT 1
Referring FIG. 3, there is shown a diagrammatic sectional view of a first embodiment of the reflective liquid crystal display in accordance with the present invention.
The lower insulative plate 1 having the pixel electrode 8 functioning as the reflector, is formed of a glass plate having a thickness of 1.1 mm, and the upper insulative plate 2 having the transparent common electrode 9 is also formed of a glass plate having a thickness of 1.1 mm, which, however, has an inner surface abraded with abrasive powder of 1000# so as to have a roughened surface, namely, a convex-concave surface.
On the lower insulative plate 1 , a non-reverse staggered structure of thin film transistor is formed in the following process. First, a chromium metal film having a thickness of 100 nm is deposited on the lower insulative plate 1 by a sputtering, and then patterned by a conventional photolithography so as to form source/drain electrodes 3 and signal interconnections.
Thereafter, the doped layer 4 , the semiconductor layer 5 and the gate oxide film 6 are succeedingly deposited by a plasma CVD (chemical vapor deposition). In this process, the doped layer 4 is formed of an n-type amorphous silicon (n + a-Si) layer doped with phosphorus, having a thickness of 100 nm. The semiconductor layer 5 is formed of an amorphous silicon having a thickness of 100 nm. The gate oxide film 6 is formed by depositing a silicon oxide film having a thickness of 300 nm and a silicon nitride film having a thickness of 100 nm.
Furthermore, a chromium metal film having a thickness of 100 nm is deposited by a sputtering, as a gate electrode layer. Then, the chromium metal film is patterned to form the gate electrode 7 and a gate interconnection, and the doped layer 4 , the semiconductor layer 5 and the gate oxide film 6 are succeedingly etched in the same pattern so as to form an island of a thin film transistor. Finally, an aluminum metal film having a thickness of 300 nm is deposited by a sputtering, and then, patterned to form the pixel electrode 8 .
On the other hand, on a roughened surface of the upper insulative plate 2 , an ITO (indium-tin-oxide) film having a thickness of 60 nm is deposited by a sputtering, and the, patterned to form the common electrode 9 .
Thereafter, the lower insulative plate 1 and the upper insulative plate 2 are adhered to each other in such a manner that the pixel electrode 8 opposes to the common electrode 9 . Here, an aligning treatment is previously carried out on each of the lower insulative plate 1 and the upper insulative plate 2 . The lower insulative plate 1 and the upper insulative plate 2 are adhered to each other by inserting a spacer such as plastic particles therebetween, and by applying an epoxy type bonding agent at a periphery of a panel. Then, a GH type liquid crystal is injected into a space between the lower insulative plate 1 and the upper insulative plate 2 , so as to form the liquid crystal layer 10 . Thus, the reflective liquid crystal display panel is completed. Incidentally, the refractive index of the glass plate is 1.5, and on the other hand, the refractive index of the ITO film is 2.0 and the refractive index of the liquid crystal material is 1.7.
As a result, a monochrome reflective liquid crystal display panel was realized, which has a sufficient brightness in practice and which enables a white display comparable to a newspaper. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
EMBODIMENT 2
Referring FIG. 4, there is shown a diagrammatic sectional view of a second embodiment of the reflective liquid crystal display in accordance with the present invention.
The second embodiment was formed similarly to the first embodiment, excluding the following: A polyimide film having a thickness of 1 μm is deposited on the roughened surface of the upper insulative panel 2 by a spin coating, and then, is annealed at a temperature of 250° C. for one hour so as to form a planarized polyimide film 11 . The ITO film is deposited on the planarized surface of the polyimide film 11 by a sputtering.
By depositing and planarizing the polyimide having the refractive index on the order of 2, it is possible to enhance the light scattering at the roughened surface of the glass plate.
EMBODIMENT 3
Referring FIG. 5, there is shown a diagrammatic sectional view of a third embodiment of the reflective liquid crystal display in accordance with the present invention.
On a lower insulative plate 1 , a switching device similar to that of the first embodiment is formed, and then, a polyimide insulating film 15 having a convex-concave surface is formed to cover the switching device and the lower insulative plate 1 . A pixel electrode 8 functioning as the reflector is formed on the polyimide insulating film 15 so that a surface of the pixel electrode 8 has a corresponding convex-concave.
The lower insulative plate 1 having the reflector, is formed of a glass plate having a thickness of 1.1 mm, and the upper insulative plate 2 having the transparent common electrode is also formed of a glass plate having a thickness of 1.1 mm, which, however, has an inner surface abraded with abrasive powder of 1000# so as to have a roughened surface, namely, a convex-concave surface.
On the lower insulative plate 1 , a non-reverse staggered structure of thin film transistor is formed in a process similar to that of the first embodiment. On the other hand, a polyimide film is deposited to have a thickness of about 2 μm on the thin film transistor by a spin coating, and preliminarily baked at a temperature of 180° C. for one hour. Furthermore, a photoresist process is carried out to cover only the polyimide film on the thin film transistor, and an etching is performed to form a convex-concave on the polyimide film covering the lower insulative plate 1 . Then, a contact hole 16 is formed through the polyimide film by a conventional photoresist process, in order to interconnect a possible pixel electrode and the thin film transistor. Further, a finishing baking is carried out at a temperature of 250° C. for one hour. An aluminum metal film having a thickness of 300 nm is deposited by a sputtering, and then, patterned to form the pixel electrode 8 . Finally, peripheral terminals are formed by a conventional patterning process.
On the other hand, on a roughened surface of the upper insulative plate 2 , an ITO film having a thickness of 60 nm is deposited by a sputtering, and then, patterned to form the common electrode 9 .
Thereafter, the lower insulative plate 1 and the upper insulative plate 2 are adhered to each other in such a manner that the pixel electrode 8 opposes to the common electrode 9 . Here, an aligning treatment is previously carried out on each of the lower insulative plate 1 and the upper insulative plate 2 . The lower insulative plate 1 and the upper insulative plate 2 are adhered to each other by inserting a spacer such as plastic particles therebetween, and by applying an epoxy type bonding agent at a periphery of a panel. Then, a GH type liquid crystal is injected into the space between the lower insulative plate 1 and the upper insulative plate 2 , so as to form the liquid crystal layer 10 . Thus, the reflective liquid crystal display panel is completed. Incidentally, the refractive index of the glass plate is 1.5, and on the other hand, the refractive index of the ITO film is 2.0 and the refractive index of the liquid crystal material is 1.7.
As a result, a monochrome reflective liquid crystal display panel was realized, which has a sufficient brightness in practice and which enables a white display comparable to a newspaper. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate. Furthermore, a contrast was improved as compared with the first embodiment.
EMBODIMENT 4
Referring FIG. 6, there is shown a diagrammatic sectional view of a fourth embodiment of the reflective liquid crystal display in accordance with the present invention.
The fourth embodiment was formed similarly to the third embodiment, excluding the following: A polyimide film having a thickness of 1 μm is deposited on th roughened surface of the upper insulative panel 2 by a spin coating, and then, is annealed at a temperature of 250° C. for one hour so as to form a planarized polyimide film 11 . The ITO film is deposited on the planarized surface of the polyimide film 11 by a sputtering.
By depositing and planarizing the polyimide having the refractive index on the order of 2, it is possible to enhance the light scattering at the roughened surface of the glass plate.
EMBODIMENT 5
Referring FIG. 7, there is shown a diagrammatic sectional view of a fifth embodiment of the reflective liquid crystal display in accordance with the present invention.
The fifth embodiment is characterized in that light scattering film 12 is provided between the upper insulative plate 2 and the common electrode 9 .
Each of the lower insulative plate 1 having the reflector and the upper insulative plate 2 having the transparent common electrode is formed of a glass plate having a thickness of 1.1 mm.
On the lower insulative plate 1 , the thin film transistor and the pixel electrode 8 are formed, completely similarly to the first embodiment.
On the upper insulative plate 2 , the light scattering film 12 is formed by depositing a paint vehicle containing a titanium oxide with a thickness of 1 μm to 2 μm, and then by baking it within an oven at a temperature of 90° C. Thereafter, an ITO film having a thickness of 60 nm is deposited on the light scattering film 12 by a sputtering, and then, patterned to form a common electrode 9 .
Similarly to the first embodiment, the insulative plate 1 and 2 are adhered and a liquid crystal material is injected into a space formed between the insulative plates 1 and 2 . Thereafter, an injection port is closed. Thus, the reflective liquid crystal display panel was completed.
As a result, a monochrome reflective liquid crystal display panel having a sufficient brightness in practice and a white display comparable to a newspaper, was realized with a low cost. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
EMBODIMENT 6
Referring FIG. 8, there is shown a diagrammatic sectional view of a sixth embodiment of the reflective liquid crystal display in accordance with the present invention.
Each of the lower insulative plate 1 having the reflector and the upper insulative plate 2 having the transparent common electrode is formed of a glass plate having a thickness of 1.1 mm.
On the lower insulative plate 1 , the thin film transistor, the pixel electrode 8 and the polyimide insulating film 15 having a convex-concave surface are formed, similarly to the third embodiment.
On the upper insulative plate 2 , a light scattering film 12 is formed by depositing a pain vehicle containing a titanium oxide with a thickness of 1 μm to 2 μm, and then by baking it within an oven at a temperature of 90° C. Thereafter, an ITO film having a thickness of 60 nm is deposited on the light scattering film 12 by a sputtering, and then, patterned to form a common electrode 9 .
Similarly to the third embodiment, the insulative plates 1 and 2 are adhered and a liquid crystal material is injected into a space formed between the insulative plates 1 and 2 . Thereafter, an injection port is closed. Thus, the reflective liquid crystal display panel was completed.
As a result, a monochrome reflective liquid crystal display panel having a sufficient brightness in practice and a white display comparable to a newspaper, was realized with a low cost. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
EMBODIMENT 7
Referring FIG. 9, there is shown a diagrammatic sectional view of a seventh embodiment of the reflective liquid crystal display in accordance with the present invention.
The lower insulative plate 1 having the reflector, is formed of a glass plate having a thickness of 1.1 mm, and the upper insulative plate 2 having the transparent common electrode is formed of a glass plate having a thickness of 0.7 mm, which has an outer surface abraded with abrasive powder of 1000# so as to have a roughened outer surface, namely, a convex-concave outer surface.
On the lower insulative plate 1 , the thin film transistor and the pixel electrode 8 are formed, completely similarly to the first embodiment.
On an inner surface of the upper insulative plate 2 , an ITO film having a thickness of 60 nm is deposited by a sputtering, and then, patterned to form a common electrode 9 .
Similarly to the first embodiment, the insulative plates 1 and 2 are adhered and a liquid crystal material is injected into a space formed between the insulative plates 1 and 2 . Thereafter, an injection port is closed. Thus, the reflective liquid crystal display panel was completed.
As a result, a monochrome reflective liquid crystal display panel having a sufficient brightness in practice and a white display comparable to a newspaper, was realized with a low cost. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
EMBODIMENT 8
Referring FIG. 10, there is shown a diagrammatic sectional view of an eighth embodiment of the reflective liquid crystal display in accordance with the present invention.
The lower insulative plate 1 having the reflector, is formed of a glass plate having a thickness of 1.1 mm, and the upper insulative plate 2 having the transparent common electrode is formed of a glass plate having a thickness of 0.7 mm, which has an outer surface abraded with abrasive powder of 1000# so as to have a roughened outer surface, namely, a convex-concave outer surface.
On the lower insulative plate 1 , the thin film transistor, the pixel electrode 8 and the polyimide insulating film 15 having a convex-concave surface are formed, similarly to the third embodiment.
On an inner surface of the upper insulative plate 2 , an ITO film having a thickness of 60 nm is deposited by a sputtering, and then, patterned to form a common electrode 9 .
Similarly to the third embodiment, the insulative plates 1 and 2 are adhered and a liquid crystal material is injected into a space formed between the insulative plates 1 and 2 . Thereafter, an injection port is closed. Thus, the reflective liquid crystal display panel was completed.
As a result, a monochrome reflective liquid crystal display panel having a sufficient brightness in practice and a white display comparable to a newspaper, was realized with a low cost. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
EMBODIMENT 9
Referring FIG. 11, there is shown a diagrammatic sectional view of a ninth embodiment of the reflective liquid crystal display in accordance with the present invention.
The ninth embodiment is characterized in that a light scattering sheet 13 is adhered on an other surface of the upper insulative plate 2 .
The lower insulative plate 1 having the reflector, is formed of a glass plate having a thickness of 1.1 mm, and the upper insulative plate 2 having the transparent common electrode is formed of a glass plate having a thickness of 0.7 mm.
On the lower insulative plate 1 , the thin film transistor and the pixel electrode 8 are formed, similarly to the first embodiment. On the upper insulative plate 2 , an ITO film having a thickness of 60 nm is deposited by a sputtering, and then, patterned to form a common electrode 9 . In addition, similarly to the first embodiment, the insulative plates 1 and 2 are adhered and a liquid crystal material is injected into a space formed between the insulative plates 1 and 2 . Thereafter, an injection port is closed. Thus, the reflective liquid crystal display panel was completed.
Furthermore, the light scattering sheet 13 , which is conventionally used in a backlight of a transparent type liquid crystal display, is adhered on an outer surface of the upper insulative plate 2 of the reflective liquid crystal display panel thus formed.
As a result, a monochrome reflective liquid crystal display panel having a sufficient brightness in practice and a white display comparable to a newspaper, was realized with a low cost. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
EMBODIMENT 10
Referring FIG. 12, there is shown a diagrammatic sectional view of a tenth embodiment of the reflective liquid crystal display in accordance with the present invention.
The lower insulative plate 1 having the reflector, is formed of a glass plate having a thickness of 1.1 mm, and the upper insulative plate 2 having the transparent common electrode is formed of a glass plate having a thickness of 0.7 mm.
On the lower insulative plate 1 , the thin film transistor, the pixel electrode 8 and the polyimide insulating film 15 having a convex-concave surface are formed, similarly to the third embodiment. On the upper insulative plate 2 , an ITO film having a thickness of 60 nm is deposited by a sputtering, and then, patterned to form a common electrode 9 . In addition, similarly to the third embodiment, the insulative plates 1 and 2 are adhered and a liquid crystal material is injected into a space formed between the insulative plates 1 and 2 . Thereafter, an injection port is closed. Thus, the reflective liquid crystal display panel was completed.
Furthermore, the light scattering sheet 13 , which is conventionally used in a backlight of a transparent type liquid crystal display, is adhered on an outer surface of the upper insulative plate 2 of the reflective liquid crystal display panel thus formed.
As a result, a monochrome reflective liquid crystal display panel having a sufficient brightness in practice and a white display comparable to a newspaper, was realized with a low cost. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
EMBODIMENT 11
Referring FIG. 13, there is shown a diagrammatic sectional view of an eleventh embodiment of the reflective liquid crystal display in accordance with the present invention.
The eleventh embodiment is characterized in that the upper insulative plate is formed of a light scattering glass plate 14 .
The lower insulative plate 1 having the reflector, is formed of a glass plate having a thickness of 1.1 mm, and the upper insulative plate having a transparent common electrode is formed of a light scattering glass plate having thickness of 0.7 mm, which is mixed with 4 weight % of a polymer having a refractive index of 2.0. For example, this light scattering glass plate 14 can be formed by impregnating a porous glass plate with a polymer.
On the lower insulative plate 1 , the thin film transistor and the pixel electrode 8 are formed, completely similarly to the first embodiment. On the upper insulative plate 2 , an ITO film having a thickness of 60 nm is deposited by a sputtering, and then, patterned to form a common electrode 9 .
In addition, similarly to the first embodiment, the insulative plates are adhered and a liquid crystal material is injected into a space formed between the insulative plates. Thereafter, an injection port is closed. Thus, the reflective liquid crystal display panel was completed.
As a result, a monochrome reflective liquid crystal display panel having a sufficient brightness in practice and a white display comparable to a newspaper, was realized with a low cost. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
EMBODIMENT 12
Referring FIG. 14, there is shown a diagrammatic sectional view of a twelfth embodiment of the reflective liquid crystal display in accordance with the present invention.
The lower insulative plate 1 having the reflector, is formed of a glass plate having a thickness of 1.1 mm, and the upper insulative plate having a transparent common electrode is formed of a light scattering glass plate having thickness of 0.7 mm, which is mixed with 4 weight % of a polymer having a refractive index of 2.0.
On the lower insulative plate 1 , the thin film transistor, the pixel electrode 8 and the polyimide insulating film 15 having a convex-concave surface are formed, similarly to the third embodiment. On the upper insulative plate 2 , an ITO film having a thickness of 60 nm is deposited by a sputtering, and then, patterned to form a common electrode 9 .
In addition, similarly to the third embodiment, the insulative plates are adhered and a liquid crystal material is injected into a space formed between the insulative plates. Thereafter, an injection port is closed. Thus, the reflective liquid crystal display panel was completed.
As a result, a monochrome reflective liquid crystal display panel having a sufficient brightness in practice and a white display comparable to a newspaper, was realized with a low cost. A color reflective liquid crystal display panel having a sufficient brightness can be realized by providing a RGB color filter on the upper insulative plate.
As seen from the above, according to the present invention, there is provided a reflective liquid crystal display which has a sufficient light scattering characteristics enabling a while display of a paper white and which can be manufactured in a process simpler than that for the conventional one.
The invention has thus been shown and described with reference to the specific embodiments. However, it should be noted that the present invention is in no way limited to the details of the illustrated structures but changes and modifications may be made within the scope of the appended claims. | In a reflective liquid crystal display comprising a first insulative plate having a reflector, a second insulative plate having a transparent electrode, and a liquid crystal layer sandwiched between the reflector and the transparent electrode, a convex-concave surface is provided at the side of the second insulative plate. With this arrangement, a desired light scattering characteristics is realized with a high image quality and a high brightness, with neither a fuzziness of displayed characters nor a double image. On the other hand, since no thin film transistor is formed at the side of the second insulative plate, the convex-concave surface can be simply formed with no necessity of depositing an insulative film covering the thin film transistor and patterning the deposit insulating film. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to an automatic engine stop-restart system for automatically stopping an engine under some predetermined conditions, and thereafter, automatically restarting the engine under other predetermined conditions.
In general, during running on a road, when a vehicle has to be stopped for a long period of time because of a traffic jam due to a signal waiting, an accident caused by another vehicle or the like, an engine may be temporarily stopped, and thereafter, restarted after the traffic jam has gone. This is done so as to avoid useless fuel consumption due to an idle operation for a long period of time.
Referring to the running through an urban district, the periods of time for vehicle stopping in the urban district comprises a fairly large percentage of the whole operating time of the vehicle, and the amount of exhaust gases and the quantity of fuel consumed therefor are not neglectable. Therefore, it is conceivable that, upon stopping of the vehicle for the signal waiting and the like during running in the urban district, the engine of the vehicle is stopped by manual operation. However, the stopping of the engine by manual operation each time of the signal waitings leads to the manually engine restarting operation, thereby resulting in a troublesome operation and a delayed starting operation of the vehicle.
There has heretofore been developed an automatic engine stop-restart system wherein, when a motor car is stopped at an intersection or the like during running through an urban district, if it is desirable to temporarily stop the engine for the purpose of improving the fuel consumption rate, the engine is automatically stopped, and thereafter, automatically restarted by a normal starting operation, which is effected at the time of starting the vehicle, such as a depression of a clutch pedal.
In the system of the type described, heretofore, rotation of the engine has been judged only by the level of an output voltage from an alternator, and an automatic stop and restart have been effected based on the result of the judgement. In consequence, there has been a possibility that, if the output voltage from the alternator in level is dropped to substantially zero despite of rotation of the engine, judgement is made that the engine does not rotate, whereby a starter is driven.
On the other hand, in the automatic engine stop-restart system of the type described, a rotational speed of the engine is detected by means of an engine rotation sensor separately of the output voltage of the alternator, and various controls are effected based on the result of the detection. Therefore, when no output is emitted from the rotation sensor due to a trouble therein despite of rotation of the engine, control means judges that the engine is stopped, and the result of the judgement causes a control output corresponding to the engine stopped condition to be fed to various actuators, thus not securing the safety of a vehicle using the system of the type described.
SUMMARY OF THE INVENTION
The present invention has been developed to obviate the above-described disadvantages of the prior art and has as its object the provision of an automatic engine stop-restart system for improvements in the safety of a motor vehicle and the reliability of the system.
To achieve the above-described object, the present invention contemplates that a function of allowing the engine to automatically stop under some predetermined conditions and to automatically restart under other predetermined conditions can be set under further predetermined conditions as deemed necessary, and judgement as to whether or not these three conditions are fulfilled is made by "and" (logical product) of a plurality of signals including two or more signals out of a signal indicating an engine rotational speed, a signal indicating a generating condition of an alternator and a signal indicating readiness or unreadiness for the start of the vehicle mounted thereon with the engine.
In an embodiment of the present invention, readiness or unreadiness for setting the aforesaid function is judged by "and" of a plurality of signals including at least a signal indicating rotation of an engine of a vehicle and a signal indicating generating condition of the alternator, readiness or unreadiness for the automatic stop of the engine is judged by "and" of a plurality of signals including at least a signal indicating that a clutch pedal is not depressed to a predetermined value, i.e., one of the signals indicating readiness or unreadiness for the start of the vehicle, and readiness or unreadiness for the automatic restart of the engine is judged by "and" of a plurality of signals including at least a signal indicating that an engine rotational speed is less than a predetermined value (i.e., the engine is stopped) and a signal indicating that the alternator is not in generating operation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing the general arrangement of the automatic engine stop-restart system according to the present invention; and
FIGS. 2 through 4 are explanatory views respectively showing operation modes in the control circuit 1, in which FIG. 2 shows an operation mode when a function of automatically stopping an engine and thereafter automatically restarting (hereinafter referred to as `ERS`) is set, FIG. 3 shows an operation mode when the engine is automatically stopped and FIG. 4 shows an operation mode when the engine is automatically restarted.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Detailed description will hereunder be given of an embodiment according to the present invention with reference to the drawings. FIG. 1 shows the general arrangement of the automatic engine stop-restart system according to the present invention, in which reference numeral 1 indicates a control circuit, to which are fed detection outputs from various sensors. Designated at 10 is a main switch by which the aforesaid ERS is set or released. After the engine is started by normal operation, if the main switch 10 is pressed under predetermined conditions, then ERS is set. Furthermore, after ERS is set, ERS can be released by manual operation by pressing the main switch 10 again. Otherwise, ERS is automatically releasable under predetermined conditions, which will be described hereinafter.
Further, designated at 12 is a vehicle speed sensor for detecting whether the vehicle is running or stopped. A detecting output from this sensor 12 is used for judgement as to whether the engine is automatically stopped. Denoted at 14 is an ignition circuit, from which ignition pulse signals are fed to the control circuit 1, where the pulse signals are processed as being an engine rotation signal. As will be described hereinafter, this engine rotation signal is used for judgement of various conditions including the setting of ERS, automatic stop and restart of the engine, and release of ERS. Designated at 16 is a clutch pedal, 18A and 18B a clutch upper switch and clutch lower switch which are operationally associated with the clutch pedal 16 for ON-OFF operation. Both of these switches are used for detecting the amount of the depression of the clutch pedal 16. The clutch upper switch 18A is turned ON when the clutch pedal 16 is depressed to a predetermined percentage to the full stroke, e.g., 30% or more, whereby a signal indicating that the clutch pedal 16 has been depressed to 30% or more is fed to the control circuit 1, so that the control circuit 1 can control the various components not to stop the engine. The clutch lower switch 18B is turned ON when the clutch pedal 16 is depressed to the full stroke, whereby a signal permitting an automatic engine start is fed to the control circuit 1.
The engine 20 is provided thereon with a water temperature sensor 22 adapted to be energized when the temperature of engine cooling water reaches a predetermined value and a hydraulic pressure switch 24 adapted to be energized by a predetermined engine oil pressure, and detection outputs therefrom are fed to the control circuit 1. Designated at 26 is a change-over switch for indicating the generation of the alternator, which is turned OFF when the alternator is in the generating operation. Denoted at 28 is a battery voltage input for detecting the conditions of a battery, and 30 a magnet switch for controlling the operation of the air conditioner, which switch is turned on while the air conditioner is in operation.
Further, denoted at 32 is a head lamp switch for turning head lamps ON or OFF, and 34 a wiper switch for detecting the operating conditions of a wiper. Use of electrical equipments such as head lamps are detected through these switches 30, 32 and 34, i.e., if these electrical equipments have high electrical load. Indicated at 36 is a turn signal switch for detecting whether the vehicle is to turn rightward or not, and 38 a door switch for detecting the opened or closed state of a door on the side of a driver's seat. Out of these detection outputs, the former is utilized as an input for judging an automatic engine stop condition, and the latter is used as an input for judging an ERS setting condition and an ERS release condition. Further, designated at 50 is a slope sensor which detects if a slope of the road surface is more than a predetermined value (2 degrees for example) or not, and, when the slope is more than the predetermined value, the slope sensor is turned ON. Denoted at 52 is an idle switch for detecting if the engine is in idling or not, and when the engine is in idling, the idle switch is turned ON. Denoted at 54 is a defogger switch for detecting if a defogger is in use or not.
After ERS is set by the main switch 10 under the predetermined conditions fulfilled, the automatic stop and restart of the engine 20 are performed as will be described hereunder. More specifically, when the conditions of stopping the engine 20 are fulfilled, the control circuit 1 feeds an engine stop signal 44 to a fuel cut relay 40, whereby the fuel cut relay 40 feeds a fuel cut signal 51 to a fuel cut solenoid, not shown, in a fuel supply system of the engine 20, and feeds an ignition cut signal 60 to the ignition circuit 14, so that the engine can be stopped. To automatically stop the engine, such an arrangement may be adopted that only the ignition cut is effected without performing the fuel cut. In this case, there is presented the disadvantage that the drive feeling is deteriorated because the engine tends to be subjected run-on.
On the other hand, under a situation where ERS is set, when the clutch pedal 16 is fully depressed during engine stopping to turn, the clutch lower switch 18B ON and the other conditions of the automatic engine start to be described hereunder are fulfilled, the control circuit 1 feeds an engine start signal 46 to a starter relay 41, whereby the starter 42 is energized, so that the engine 20 can be started.
Description will hereunder be given of the respective operation modes of the automatic engine stop-restart system as shown in FIG. 1 including the ERS setting mode, the engine stop mode and engine start mode after ERS is set with reference to FIGS. 2 through 4. FIG. 2 shows the operation mode of ERS setting, and, when "and" of the following five conditions is fulfilled as shown in FIG. 2, ERS setting can be done.
(1) ERS setting has been released.
(2) The main switch for ERS setting is on.
(3) The engine is rotating, the engine rotational speed is 400±50 rpm or more, for example.
(4) The alternator is in the generating operation.
(5) The door on the side of the driver's seat is in the closed state (detected by the door switch 38).
There are two cases of releasing ERS setting in (1), including one case of manually releasing through pressing on the main switch 10 and the other case of automatically releasing. These two cases will be described hereinafter. Judgement as to whether the engine is rotating or not is made through the engine rotational speed in (3) and the generating condition of the alternator in (4). This is done for reliably detecting if the engine is rotating or not.
FIG. 3 shows the operation mode of the automatic engine stop. As shown in FIG. 3, when "and" of the following conditions (1) through (13) is fulfilled, the engine is automatically stopped.
(1) ERS has been set.
(2) The engine rotational speed is a predetermined value, e.g., 850 rpm or less.
(3) Both the clutch upper switch 18A and the clutch lower switch 18B are OFF, i.e., the clutch pedal 16 has not been depressed to a predetermined value or more.
(4) The turn signal switch 36 is OFF, i.e., a right turn signal is not emitted.
(5) The head lamp switch 32 is OFF.
(6) The wiper switch is OFF.
(7) The water temperature sensor 22 is OFF, i.e., the temperature of engine cooling water remains within a specific temperature range, e.g., 75° C.˜105° C.
(8) The air conditioner magnet switch 30 is OFF.
(9) A predetermined period of time, 4 SEC for example, has elapsed after the engine is started by ERS.
(10) The vehicle is in a stopped state.
(11) The slope sensor 50 is OFF.
(12) The idle switch 52 is OFF.
(13) The defogger switch 54 is OFF.
Out of above-described conditions, "(2) The engine rotational speed is 850 rpm or less" is adopted in consideration of that during racing the automatic engine stop is not to be performed, and "(3)" is provided for the reason that the clutch pedal can be depressed only when the engine is started or the gear shift is effected, and in this system the engine can be restarted by the depression of the clutch pedal.
(4) is adopted as a condition of judging because, at the time of right turn of the vehicle, the driver is required to pay attention to ascertaining the presence of a car running in the opposite direction and the like, and, it is not desirable to stop the engine under the aforesaid conditions. The reason why (5), (6), (8) and (13) are utilized for judging the engine stop is that it is avoided to overdischarge the battery due to the engine stop at a high electrical load. Condition (7) is adopted for not stopping the engine in the low and high temperature ranges of the engine cooling water because it is difficult for the engine to start in those temperature ranges. Condition (9) is adopted for preventing the automatic engine stop and restart from being repeated within a short period of time. Condition (10) "The vehicle is in a stopped state" is judged by the presence of the change in level of a detection output (pulse train signal) of the vehicle speed sensor 12.
As has been described hereinabove, in the automatic engine stop-restart system according to the present invention, the engine rotation signal and the clutch signal operationally associated with the clutch pedal are used as the conditions of judging whether the automatic engine should be stopped or not.
FIG. 4 shows the operation mode of the automatic engine start by ERS. As shown in FIG. 4, when "and" of the following conditions (1) through (4) is fulfilled, the engine is automatically restarted.
(1) ERS has been established.
(2) The engine rotational speed is less than a set rotational speed, e.g., 50 rpm or less.
(3) The alternator is not in the generating condition.
(4) The clutch lower switch 18B is ON, i.e., the clutch pedal is fully depressed.
Out of the above-described conditions, (2) and (3) are adopted for judging the engine stopped state. Both the engine rotation signal and the alternator's generating condition signal are adopted because, even when either one of the engine rotation signal and the alternator's generating condition signal is not fed to the control circuit 1 due to some reason or other despite of rotation of the engine, reliable judgement on the rotation of the engine can be performed.
Release of ERS after ERS has been set is performed as follows:
(A) To release by manual operation
After the main switch 10 has been pressed, if the main switch 10 is pressed again, then ERS setting is released.
(B) To automatically release
(1) When the engine is restarted by manual operation of the ignition switch
(2) When the door on the side of the driver's seat is opened
(3) When the battery is lowered in voltage
(4) When a predetermined period of time, e.g., 2 SEC, has elapsed until the engine rotational speed reaches a certain value, 550 rpm for example, at the time of restart by ERS
In all of the above-described cases, ERS setting is automatically released. Out of the above-mentioned conditions, (1) is adopted for that, when the engine is restarted by manual operation of the key switch in spite of that the engine has been automatically stopped by ERS, ERS must be released to prevent ERS to drive the starter again. (2) is adopted for that, in consideration of a replacement of the driver by a new one, when the door switch 38 is actuated, ERS is released, so that a driver unfamiliar with ERS may not be confused. (3) is adopted because, when the ERS is kept on under lowered battery capacity, the restart cannot easily be effected. Similarly, (4) is adopted for that, in consideration of the lowered capacity of the battery, when the engine is restarted under the condition (4), ERS is released, and thereafter the engine is started and stopped by means of an ordinary ignition switch.
In addition, in the description of FIG. 3, there have been included signals of use of the air conditioner and use of the defogger. However, needless to say, in the vehicle without those components, there is no necessity for providing those two types of signals. | In automatically stopping or restarting an engine on a basis of detecting an operational state of each component of a vehicle with the engine mounted thereon, judgement as to whether first condition of setting the function of allowing the engine to automatically stop and restart, second condition of automatically stopping the engine after the function is set and third condition of automatically restarting the engine after the function is set are fulfilled or not, respectively, is made by "and" of a plurality of signals including at least two or more signals out of a signal indicating an engine rotational speed, a signal indicating the generating condition of an alternator and a third signal indicating readiness or unreadiness for starting of the vehicle. | 5 |
The present invention relates to a liquid flow meter, and more particularly to a liquid flow meter capable of sensing extremely low flow rates.
BACKGROUND
Liquid flow meters are well known, and one such type of flow meter is described in U.S. Pat. No. 3,867,840, BAATZ, in which the liquid to be measured is supplied to a chamber in tangential direction. A rotor is retained within the chamber, the liquid being removed from the chamber in axial direction. The rotor carries vanes. As the fluid is introduced into the chamber, termed a swirl chamber, it impinges on the rotor vanes to rotate the rotor. Rotation is sensed by an optical-electrical evaluation device, the speed of the rotor, and the number of revolutions per unit time, determining the flow speed of the liquid, and hence the quantity of liquid being supplied.
The rotor has some inertia. Liquid which is in the chamber, and even after new liquid has been supplied, will continue to swirl therein, thus continuing further rotation of the rotor although no further liquid is being supplied. The structure necessarily requires some clearance between the vanes on the rotor and the walls of the swirl chamber, which permits some liquid to leak past the rotor. The accuracy of measurement at extremely low fluid flow, thus, is impaired by the possibility of such leakage from the inlet to the outlet duct in the swirl chamber.
It has also been proposed to locate a rotor directly within a fluid duct--see German Patent Disclosure Document DE-OS No. 29 11 826, WERKAMM. The rotor is essentially drum-shaped and is formed with helical ribs at its circumference. Axial ribs are located within the duct upstream from the rotor in order to direct the fluid flow in axial direction with respect to the rotor and to render it uniform. Fluid passing the rotor will meet the helical ribs, thus rotating the rotor.
The rotor, of course, must have some clearance within the duct in which it is retained and some of the fluid will flow along the duct without contacting the ribs of the rotor. For extremely low flow quantities, the measuring results, therefore, will not be accurate, and the fluid meter will not only be non-linear but may give random outputs not in accordance with actual flow. Further, if flow is stopped, the rotor will continue to run on for some time, so that the run-out of the rotor also will cause measurement errors.
THE INVENTION
It is an object to provide a liquid flow meter which has a wide operating range, so that even extremely small flow quantities can be measured accurately, and in which interruption of liquid flow will cause a zero or null signal, without run-on of a rotating element. The flow quantity may, for example, be flow of fuel to an internal combustion engine which, as well known, is extremely small when the engine operates under idling conditions. The flow meter should be capable of measuring the flow and variations thereof under engine idling.
Briefly, a rotor is located within a flow circuit which is so arranged that the inlet duct supplies liquid to the rotor in the region of the axis of the rotor, the outlet duct receiving liquid from exit openings at the circumference of the rotor, and forming an outlet duct chamber surrounding the rotor, preferably so constructed that two diametrically oppositely positioned outlet ducts emanate from the openings, leaving in approximately tangential direction.
In accordance with a feature of the invention, two rotors may be located on a single shaft, with one rotor receiving liquid from a supply source, and the second rotor, associated with a second exit chamber, receiving liquid which is returned from a utilization source, the difference between fluid flow being a measure of utilization of the liquid. The directions of rotation of the two rotors are in opposite sense, and the exit openings, preferably, of the second rotor are directed oppositely to those of the first.
For calibration, a bypass can be provided in accordance with a feature of the invention, which has a variable cross section, for example by arranging a slit or diaphragm with a suitable opening, so that operation of the rotor can be calibrated with respect to total flow to be sensed.
The flow meter has the advantage that, by directing flow from centrally of the rotor outwardly, the rotor is rotated only by the reaction force of the liquid leaving the rotor. Since even very small flow quantities must emanate or exit from the rotor openings, even the smallest flow will cause reactive forces to act on the rotor, so that extremely low liquid flow per unit time can be measured with high accuracy. Rotation of the rotor itself can be sensed by any suitable and well known opto-electric or electromagnetic evaluation device. Thus, instantaneous fuel consumption in an automotive engine, particularly when directly installed in an automotive vehicle, as well as determination of total fuel consumption, can be indicated.
The exit chamber which receives the liquid from the rotor can be so arranged that the liquid which exits from the rotor, at least in part, will flow in opposite direction to rotor rotation. Thus, run-on of the rotor after liquid flow has stopped is effectively braked by the fluid still present within the chamber and circulating in a direction opposite that of rotor rotation.
In accordance with a particularly suitable embodiment of the invention, the rotor is essentially disk-shaped, having two exit openings thereon and vanes or blades extending from the rotor axis to the respective openings, preferably in form of a spiral. This arrangement effectively prevents formation of turbulence of the liquid in the rotor, as well as gassing of the liquid, and the formation of gas bubbles. To obtain essentially uniform, linear flow in the liquid being supplied to the rotor, the rotor is preferably secured to a shaft which is located within the flow duct or channel leading fluid thereto. Guide ribs can be located on the inner wall of the supply channel. This arrangement is particularly suitable to effect braking of the rotor and prevent run-on, and especially so if the inner edges of the vanes or ribs are inclined with respect to the liquid duct.
Combining two flow meters together, for example two rotors in a common housing, provides a measure of fluid utilization, for example fuel utilized by a combustion engine, in which a portion of the fuel which is supplied and not utilized is returned to the supply source. In this system, a second line provides for the return flow. Placing two rotors in a coaxial arrangement permits locating the two rotors in a compact system in which the rotation of the rotors is opposite each other.
An adjustable bypass--if used--permits control of the rotor speed, and hence the number of pulses being emitted, for example by an opto-electronic scanner or the like, to limit the speed of the rotor to a predetermined maximum value. The inlet is then connected to the outlet by a bypass or calibration duct, bypassing passage of the fluid through the rotor. The cross section of the bypass can be changed, for example under servo control, which is also capable of providing output signals relating flow to rotor speed, if a given speed is known to result in a given flow under then adjusted and controlled bypass conditions.
DRAWINGS
FIG. 1 is a longitudinal sectional view through the flow meter having a disk-shaped rotor;
FIG. 2 is a cross section taken along line II--II which, it should be noted, is a broken section;
FIG. 3 is a fragmentary view through the central portion of the rotor, to an enlarged scale;
FIG. 4 is a longitudinal section illustrating another embodiment of the invention and using a tubular rotor;
FIG. 5 is a perspective view of the rotor of FIG. 4; and
FIG. 6 is a vertical cross-sectional view through a tandem flow meter utilizing the embodiment of FIGS. 4 and 5, in which the rotors are located on a common shaft, and rotate in respectively opposite directions.
DETAILED DESCRIPTION
The flow meter of FIGS. 1-3 is specifically designed to sense fuel consumption in an internal combustion (IC) engine. The flow meter 10 can thus be included in the fuel supply line from a fuel tank to, for example, a carburetor or a fuel injection control apparatus of an IC engine. The fuel is supplied by a fuel pump, not shown, and flows through the flow meter 10. The flow direction of fuel is shown by arrows.
Fuel is first conducted to an inlet chamber 11, then via an inlet opening 12 into a flow duct 13. From flow duct 13, the fluid passes through a rotor 14 into a chamber 15. From chamber 15 it passes through an outlet opening 16 to the outlet duct or outlet connection 17.
The inlet chamber 11 is connected to a supply duct--not shown. The outlet duct 17 is connected to a removal line, likewise not shown. Any suitable connection, such as compression fittings or flanges, may be used. The rotor 14 is secured to a rotor shaft 18 which is rotatably fitted in a bearing 20 which closes off the lower end of the flow duct 13. The bearing 20 is fitted into the lower portion 19 of the housing retaining the flow meter 10.
The upper housing portion 21 of the flow meter 10 closes off the top of the chamber 15 towards the upper side of the flow meter. A second bearing 22 for the upper end of the rotor shaft 18 is secured in the upper portion 21 of the housing. The channel or duct 13 is shaped to provide uniformly directed, preferably essentially non-turbulent, flow in an axial direction with respect to the shaft. To obtain this uniform flow, three guide ribs 23 are formed in the inner portion of the duct 13, uniformly distributed throughout the circumference of the duct 13.
The rotor 14 is concentrically surrounded by the outflow chamber 15, as best seen in FIG. 2, which is a cross section of the flow meter along line II--II which, as seen in FIG. 1, is an offset section. Fluid flowing upwardly through the duct 13 is received within the rotor in the region of the rotor shaft. The fluid flows through the rotor and leaves by two exit openings 24 formed at the outer circumference of the rotor 14. Rotor 14 is essentially a circular disk. Upon leaving the rotor 14, the fluid will reach the outflow chamber 15. The openings 24 of the rotor are arranged to guide the fluid in essentially tangential direction, and they are, therefore, approximately tangentially placed. They are positioned at the outer circumference of the rotor 14 in diametrically opposite relation to each other, and extend in the same circumferential direction.
The rotor has two guide vanes 25 extending from the region of the rotor axis towards the outlet openings 24. The guide vanes 25 are located within the interior of the rotor--see FIG. 2--and are formed as a logarithmic spiral, defining a wider inner chamber and terminating at the narrow outlets 24. The shape of the vanes 25 is so arranged that the flow resistance is reduced and turbulence of the fluid passing through the rotor should be prevented.
Rotor 14 has a hub 26--see FIG. 3--with which it is secured to the rotor shaft 18. The hub 26 extends from the top into the flow duct 13. The guide ribs 23 are located in this region about the hub 26. The inner ends of the guide vanes 25 of the rotor 14 are located immediately thereabove. The inner edges 25a--see FIGS. 2 and 3--are chamfered or inclined in the direction towards the flow duct 13 in order to brake the rotor 14 at free running or idling. The rotor 14 is closed off at its bottom by a plate 27 which has uniformly distributed projections 28 in the form of lamellae or vanes which cooperate with an optoelectrical transducer 29 fitted into the bottom of the flow chamber 15, and transducing movement of the rotor 14 into electric pulses.
The inlet chamber 11 has a bypass calibration duct 9 communicating therewith which leads directly to the outflow chamber 15. The inlet chamber 11 is formed with an enlarged entry region 11a in order to compensate for pressure variations. The calibration duct 9 is located in communication with the pressure variation compensation region 11a. The duct 9 is formed with a slit 8 at the end facing the outlet flow chamber 15. The slit 8 may, for example, be about 2 mm and 0.2 mm wide. The slit can be, selectively, covered by a cover or diaphragm 7 extending from a wall of the chamber 15, and secured to the upper housing portion 21.
Operation: Liquid, the flow of which is to be metered, for example fuel supplied to an IC engine, upon being supplied, flows in the direction of the arrow to the inlet opening 12 into the flow duct 13. The liquid flow is straightened by the ribs 23, so that the liquid will rise upwardly in the axial direction of the rotor within the duct 13. The liquid is admitted to the rotor centrally, through an opening in the center, surrounding the rotor shaft in the region of the axis of rotation thereof, and hence the fluid will flow into the rotor, will flow along the guide vanes 25 and will exit at the outside of rotor 14 through the exit openings 24. The fuel flow will thus exert a force on the guide vanes 25, causing the rotor to rotate. The fluid coming from the exit openings 24 of the rotor then flows in a circumferential direction within the outflow chamber 15. The rotor 14 rotates in the opposite direction of fluid flow. The fluid then flows through the outlet opening 16 to leave the outflow chamber 15 through the outlet duct 17, and from then on to the fuel line.
Depending on the supply quantity, rotor 14 is rotated at, respectively, higher or lower speed. The opto-electronic transducer 29 provides an electrical pulse each time one of the ribs or lamellae 28 of the rotor plate passes the transducer 29. The pulse frequency, then, can be used as a measure of instantaneous fuel consumption of the IC engine, and displayed; summing the pulses will provide a measure of total fuel consumption and, if desired, remaining fuel within a tank can be indicated by subtracting the fuel used from tank capacity.
The pulse frequency, that is, the number of ribs or lamellae 28, is so fixed that flow meters which are even at the limit of manufacturing tolerances provide outputs even if the calibration bypass duct 9 is completely covered. Upon rotating the upper portion 21 of the flow meter 10, the diaphragm cover 7 is moved such that a portion of the slit 8 will be freed, that is, only a lesser portion of the slit 8 will be covered. A lesser quantity of fuel can thus be passed from the inlet entry region 11a to the outflow chamber 15 while bypassing the rotor 14 in a parallel fluid flow path. Upon constant through-flow, the rotor speed, thus, is decreased.
The output from the flow meter can thus be easily calibrated, since a predetermined flow rate can be matched to a predetermined pulse rate and, if the flow meter should not operate in accordance with the given criteria, rotation of the upper portion 21 can be used to more or less cover the slit 8, and thus calibrate the flow meter and positively relate the output frequency from transducer 29 to a given flow.
Gas bubbles, vapor bubbles, and other disturbances within the fuel may lead to erroneous measuring results if they reach the rotor 14. By installing the flow meter in a vertical position as shown in FIG. 1, with the chamber entry region 11a at the inlet, and placing the calibration duct 9 in the upper region of the chamber 11 or, rather, in the space of entry region 11a which forms a quieting chamber, and leaving the slit 8 open for at least a portion of the width thereof by suitable positioning of the covering strip of diaphragm 7, gas and other disturbances within the liquid can be bypassed and will not interfere with proper measuring results upon rotation of the rotor.
The flow meter can readily be made to measure such extremely small flow rates as, for example, 1/2 liter per hour, which is, for example, a fuel consumption of an IC engine upon idling; yet, the measuring range is extremely large, since the same meter can also accurately provide outputs of fuel consumption to 100 liters per hour, which may correspond to full load operation. The measuring results obtained are accurate both at the low as well as at the high end of through-put, with a range of 1:200.
It is particularly important that the rotor stop immediately when fuel flow stops, even though the rotor may have been running fast, and flow is suddenly interrupted. This is obtained, in accordance with the embodiment shown, by the external, and particularly outer circumferential shape of the rotor 14 and the shape of the outflow chamber 15. The fuel is ejected from the rotor 14 in a direction which is counter the direction of rotation of the rotor so that, if no additional flow should emanate from the rotor openings 24, the still present fluid circulating within the circumference of the rotor chamber will have a braking effect on the rotor as the still present fluid remains also in the outlet opening 16 which is located above the rotor in chamber 15. Additionally, the rotor 14 is braked by the projections 28 at the bottom side thereof, which are operating within the chamber 15, filled with fluid. An additional braking effect is obtained by the shape of the inclined edges 25a at the inner side of the vanes 25. Upon rotation of the rotor, with no fluid being supplied, the free-running rotor will cause turbulence within the fluid still present in the region about the rotor axis. This turbulence continues upstream within the duct 13 and is braked by the guide ribs 23. Thus, energy which would cause movement of the rotor is removed therefrom. The rotor, thus, is rapidly braked if the through-put or flow of fluid therethrough should stop. The still existing fluid within the flow meter then causes rapid braking.
Embodiment of FIG. 4: A flow meter 30 has a rotor 31 formed by a generally T-shaped tubular section, the opposite ends of which are closed. The rotor 31 is best seen in FIG. 5, and secured on a rotor shaft 32 which is retained in bearings positioned in the inlet chamber or duct 33 and in the outflow chamber 34. A flow duct 35 is formed by a tubular extension 35a surrounding the rotor shaft 32--see FIG. 4--to permit fluid to rise upwardly in axial direction as it flows through the flow meter. The fluid then divides, part moving in diametrical direction in the two sections 31a, which have outflow openings 36 tangentially arranged with respect to the outflow chamber 34 which, in plan view, is circular. The remaining portion of fluid passes through the other tubular section 31a, leaving by the other outlet 36, the two outlets 36 in the two sections 31a being located at respectively opposite directions.
The fluid, thus, leaves from the two outlet openings 36, and the rotor 31 is rotated within the outflow chamber 34 in the direction of the arrow as illustrated in FIG. 5 due to reactive forces acting on the rotor 31. An opto-electrical transducer 37 transmits rotation of the rotor into electrical signals to provide output indication for flow rate as well as flow quantity.
The inlet chamber 33 of the flow meter 30 is connected to a supply line 38 and the outflow chamber 34 to a removal line 39.
The rotor 30 is simple to construct; braking upon sudden disconnection of flow of fluid may not, however, be as effective as in the embodiment of FIGS. 1-3. Yet, such a flow meter can be used particularly desirably if the fluid is supplied from a fluid supply line to a consuming station, and the fluid which is not consumed therein is returned by a return line to a supply tank, for example.
FIG. 6 illustrates an embodiment in which the construction of FIGS. 4 and 5 is particularly suitable. A second rotor 40 is located on the same rotor shaft 32a as the rotor 31. Fluid which is conducted through the inlet 38 and removed through outlet 39 is then conducted to a utilization or consumption station, with that quantity of fuel which is not consumed being conducted to the inlet chamber 43, and then through the flow duct 44 to the rotor 40. The fluid which has not been consumed is then conducted through the exit openings 45 of rotor 40 into the outflow chamber 41 and from there to the return line 46.
The outlet openings 45 on the tubular ends of the second rotor 40 are directed in opposite direction to the outlet openings of the first rotor 31. Thus, rotor 40--if it were independent--would operate in a direction of rotation counter that of rotor 31 upon flow of fluid thereto. Since both rotors 31 and 40 are secured to the same rotor shaft 32a, however, torques in opposite directions are effective on the shaft so that the entire system will measure the difference between the fluid passing through the rotor 31 and the fluid passing through the rotor 40. Assuming that the fluid in rotor 40 is less than that in rotor 31, the system will move in the direction of rotation of the rotor 31, as given by the position of its outlet openings 36. If no fluid, for example fuel to an IC engine is utilized, the supply and return flow quantity will be equal. The respectively reverse torques acting on the rotors 31 and 40 will cancel each other, and the overall system will stop immediately.
It is not necessary to recognize the direction of rotation of the rotors in any one of the embodiments; thus, the transducers 29, 37 need not specifically sense the direction of rotation of the rotor since the rotor, upon reversal of the flow direction, would merely stop.
Various changes and modifications may be made, and features described in connection with any one of the embodiments may be used with any of the others, within the scope of the inventive concept. | To measure a wide range of flow rates, and particularly such low flow rates as 0.5 liters per hour, while being able to accurately also measure rates of about 100 liters per hour, fluid is introduced axially into a rotor (14, 36, 40) which has outlet openings (24, 36, 45) positioned at their circumference, the rotor being rotated by reaction on the rotor upon fluid flow from the outlet openings. The rotor operates within a fluid flow chamber (15) from which is conducted outwardly through a duct positioned thereabove. Inflow of fluid may be guided for linear flow by guide ribs (13). The rotor may be a hollow disk-like structure (FIGS. 1-3) with spiral guide vanes therebetween, or a T-shaped tubular structure (FIGS. 4-6). If fuel consumption of an internal combustion engine is to be measured in which pressurized fluid is supplied to the engine and excess returned, two such flow meters can be combined on a common shaft, with respectively oppositely facing outlet openings (36, 45), so that differential flow only is being measured, hence accurately measuring fuel consumption by the engine. Rotation of the rotor is sensed by an electro-optical sensor (29, 37). | 6 |
This invention relates to a woven diaper with panel-shaped zones which vary in their moisture-absorbing capacities. More particularly it relates to such diapers wherein the absorbency differences are due to varying arrangements of spun yarns composed of absorbent fibers and spun yarns composed of blends of absorbent and non-absorbent fibers.
BACKGROUND OF THE INVENTION
It is known to weave diapers in the form of rectangular blanks, adapted to be folded to smaller rectangles for application to babies. It is also common practice to weave such diapers in a multilayered gauze-like construction, and to prefold such diapers and sew the folded blank to secure the folds in fixed position. These are termed prefolded diapers or simply prefolds.
It is also realized that wet diapers next to a baby's skin promote discomfort and even diaper rash, and attempts have been made to create diapers in which the face of the diaper to be applied next to the skin is of a hydrophobic or non-absorbent nature. Such attempts are illustrated by U.S. Pat. Nos. 3,113,570 and 3,216,421. All such previous attempts, however, have been unsuccessful due to the fact that they utilized hydrophobic yarns, such as yarns of polyamide, polyester, polyolefin and the like. Such yarns, while of lower absorbency than cotton or rayon yarns, also have a much lower shrinkage in the normal processes of purification of the woven fabric, and the subsequent multiple launderings to which the diaper is subjected. Normally, purification of a cotton diaper fabric, woven in the grey state, involves a shrinkage of between 10% and 11% in the warp direction. Since hydrophobic yarns, composed of synthetic polymers, show little or no shrinkage in such a purification process or subsequent laundering, the result is buckling and distortion of the plane of the fabric, with the development of corrugations and uneven hems, when such yarns are used in prior art diapers.
Furthermore, the elongation characteristics of hydrophobic yarns differ from the characteristics of cotton or rayon hydrophilic yarns, making them difficult to handle in the slashing and weaving process, which involves the use of a warp beam of yarns under considerable tension. Such a warp beam, composed of many hundreds of warp yarns, is conventionally fed to the loom with the yarns protected by a water-soluble size or coating removed in subsequent processing. Hydrophobic yarns are not readily wet by such coatings, necessitating special processing to assimilate them into the warp beam.
BRIEF DESCRIPTION OF THE INVENTION
It has now been found that the disadvantages of diapers comprising hydrophobic yarns and hydrophilic yarns, as set forth above, can be eliminated by the use of warp yarns which are an intimate blend of hydrophobic fibers and hydrophilic fibers, preferably in a range of 50% to 65% hydrophobic fibers and 50% to 35% hydrophilic fibers. Such yarns may be considered as semi-absorbent, and are so designated in this application, in contrast to absorbent yarns such as bleached cotton or rayon.
The present invention, therefore, relates to diapers comprising multiple layers of different absorbency characteristics. At least one layer, intended to be applied next to the infant's skin, is less moisture absorbent than other layers of the diaper due to a warp structure therein consisting substantially of semi-absorbent yarns, whereby moisture is transmitted to and retained by other layers of the diaper which have a higher absorbent capacity.
Such diaper fabrics, comprising a multiplicity of generally rectangular panels or zones, varying in absorbency characteristics and intended to be folded to form a diaper, are termed herein multipaneled diapers of zoned construction.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood by reference to the following description and drawings, in which;
FIG. 1 is a plan view of a diaper according to one embodiment of the invention.
FIG. 2 is a cross-sectional view of the diaper of FIG. 1 along the line C--C.
FIG. 3 is a view of the diaper of FIG. 2 folded for sewing at 30 and 32.
FIG. 4 is a perspective view of a finished diaper according to this invention.
FIG. 5 is a cross-sectional view of another embodiment of a diaper according to this invention.
FIG. 6 is a view of the diaper of FIG. 5 folded for sewing at 64 and 66.
FIG. 7 is a cross-sectional view of the diaper of FIGS. 1 and 2 with an inserted absorbent layer 68.
FIG. 8 is an enlarged plan view of a twill weave used in certain panels in some of the diapers of this invention.
DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a diaper blank is shown as consisting of a multiplicity of rectangular panels 12, 14, 20, 22, and 24, bounded on its outer edges by selvages 26 and 28, and connected internally by the wear-strips 16 and 18 which become the outer edges of the diaper after folding for use.
The central panel 24, preferably of single ply construction, consists substantially of semi-absorbent warp yarns which are a blend of hydrophobic fibers such as polyester, polyamide, polyacrylic fibers, and the like, and hydrophilic fibers such as cotton or rayon. In the finished diaper this panel is applied next to the infant's skin, where, due to its semi-absorbent nature, it tends to wick away substantial amounts of urine from the skin and transfer it to the more absorbent panels of the diaper.
As shown in FIG. 2, a cross-section of FIG. 1 along the line C--C, panels 12, 14, 20, and 22 are preferably of two-ply construction, for softness and ease of laundering. These four panels may be of 100% absorbent warp yarns, or may be a mixture of absorbent warp yarns and semi-absorbent warp yarns in which mixture at least 50% of the warp yarns are absorbent. It will be apparent to those skilled in the art that in order to provide diapers in which the panels possess substantially equal shrinkage tendencies in laundering, the warp yarns in panels 12, 14, 20 and 22 should not deviate in shrinkage tendency too far from the semi-absorbent warp yarns constituting the central panel 24. In ggeneral, depending on the size and twist of the yarns employed as well as the design and the tightness of the weave, satisfactory results are obtained when a central panel 24, composed of 100% semi-absorbent warp yarns, is bounded by absorbent panels 12, 14, 20, and 22 in which the warp yarns vary from 50% absorbent yarns-50% semi-absorbent yarns to 100% absorbent yarns.
For simplicity in weaving, it is preferable that the two-ply panels 12, 14, 20, and 22 be of square wave, although twill weave, basket weave, birdseye weave, and other weaves common in the diaper industry may be employed. The filling yarns in the diapers of this invention are preferably absorbent, throughout the body of the diaper. In the single-ply zones of the diaper, including central panel 24, wear strips 16 and 18, and selvage edges 26 and 28, a twill weave, such as FIG. 8, is preferred since such a weave adds flexibility and softness to the single-ply zones and helps to equalize warp tensions as the weave changes from single-ply to two-ply.
In forming the diaper blank of FIGS. 1 and 2 to form a prefolded, ready-to-use diaper, a folding operation is performed as shown in FIG. 3. Selvage edge 28 is brought over to point B of FIG. 2 and selvage edge 26 to point A, after which these edges are stitched along the length of the diaper fabric, as at 30 and 32 in FIGS. 3 and 21. Individual diapers of desired length are cut from the continuous fabric and secured at the cut edges by overstitching as at 34 and 36 FIG. 4, which represents a finished pefolded diaper.
SPECIFIC EMBODIMENT OF THE INVENTION
A diaper blank of zoned construction, according to FIGS. 1 and 2, was produced in a 39 inch width, using 27's cotton yarns in the filling of the fabric. At the sides of the blank, panels 12 and 14 were woven in tubular form in a square weave, with a total count of 92 warp ends and 54 picks per inch, or 46 by 27 yarns in each layer. Panels 12 and 14 were approximately 11 inches each in width, with warp yarns consisting of an equal number of randomly distributed 31's cotton yarns and 32's spun yarns of blended 50% polyester fibers and 50% cotton fibers, interwoven in a twill weave at selvages 26 and 28.
Inwardly adjacent to panels 12 and 14 the wear strips 16 and 18 were formed, each approximately 11/4 inches in width, in single layer twill weave, with 92 warp ends and 54 picks per inch, the warp yarns being a 50--50 mixture of cotton yarns and 50% polyester-50% cotton spun yarns as in panels 12 and 14.
Panels 20 and 22, adjacent to wear strips 16 and 18, were each approximately 4 inches wide and of yarn structure identical with panels 12 and 14.
Panel 24, lying between panels 20 and 22, is approximately 61/2 inches wide, woven in a single layer, twill weave, with a warp consisting of 46 ends per inch, each warp yarn being a blend of 50% polyester fibers and 50% cotton fibers. The filling picks were cotton, 54 per inch.
After full-width scouring and bleaching, the fabric was plied with an absorbent insert, 68 in FIG. 7, placed on the center panel 24. This insert may be of an absorbent open-cell foam, of woven or nonwoven fabric, or preferably, of a needle-punched fibrous batt, as of blended cotton-polyester fibers weighing 3 to 6 oz. per square yard. The assembly was folded as in FIG. 7 and stitched along the lines 30 and 32, as in FIGS. 4 and 7, thus securing the insert and the plied fabric together. After cutting the assembly to 20 inch lengths, the cut edges were secured by overedged stitching as shown at 34 and 36 in FIG. 4.
The resulting prefold diaper, as shown in FIG. 4, has a lower central panel, 24 in FIGS. 2 and 3, consisting of absorbent cotton filling yarns and semi-absorbent warp yarns, consisting of a blend of cotton fibers and polyester fibers, as described above. This panel, therefore, is less absorbent than the panels constituting the rest of the diaper, and is intended to be placed next to the infant's skin. To insure proper application, the upper face of the diaper may be marked with a suitable laundry-proof index mark, or the selvage edges, 26 and 28 may incorporate a colored yarn or yarns.
When the above diaper is compared with a similar diaper composed of all absorbent cotton yarns in a moisture-distribution test, the panel 24 is noticably dryer to the touch than its all-cotton counterpart, and weight measurements show that it has retained only 40% of the moisture retained by an all-cotton panel.
OTHER EMBODIMENTS OF THE INVENTION
If it is desired to produce a diaper which has a center panel of lower absorbency on both the upper and lower surface, such a diaper is provided by constructing the diaper blank 40 in accordance with FIG. 5. The selvage edges 60 and 62 correspond in count and weave to the selvage edges 26 and 28 of the specific embodiment, above. Similarly, the two panels 56 and 58 correspond in all details to the panel 24 of FIG. 3 and the specific embodiment. The tubular panels 42, 44, 50 and 52 are of the same construction as panels 20 and 22 of the specific embodiment, and the wear strips 46 and 48 duplicate the wear strips 16 and 18 of the specific embodiment.
The tubular center panel may be of a construction identical with the absorbent panels 12 and 14 of the specific embodiment, or they may comprise heavier cotton yarns, such as 20's or heavier, for added absorbency. Such heavier yarns may require a lower twist multiple than the 31's used throughout the warp in the rest of the diaper, in order to match the shrinkage characteristics of the other panels. However, a lower twist multiple will not decrease the abrasion characteristic of the diaper since this panel 54 is protected by the layers 56 and 58 in the end product.
The diaper blank of FIG. 5, after purification is folded as shown in FIG. 6 and stitched at 64 and 66 to form a prefold diaper with central semi-absorbent panels on each face and a more absorbent panel between those faces. | Diapers are woven with a central panel comprising warp yarns which are a blend of hydrophobic fibers and hydrophilic fibers. Unlike yarns which are composed entirely of hydrophobic fibers, blended yarns of this type may be readily processed by conventional means through the slashing, weaving, and scouring processes. The central panel thus produced will, in use, remain dryer than panels composed entirely of hydrophilic yarns. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION(S)
[0001] Applicant claims the priority date of U.S. Provisional Application 60/420,367, filed Oct. 22, 2002.
FIELD OF THE INVENTION
[0002] The present invention includes a method for making process cheese-type products, and products made by the process, by utilizing high shear in relation to the moisture content. In particular, the present invention relates to a method of making selected process cheese-type products through the utilization of high shear so that additional moisture can be added while retaining the organoleptic and physical properties of the process cheese-type products as if the additional moisture had not been added.
BACKGROUND OF THE INVENTION
[0003] As used herein, the term “process cheese-type products,” are defined to include those products known and referred to as “pasteurized process cheese,” “pasteurized process cheese food,” “pasteurized process cheese spread,” and “pasteurized process cheese product.” “Process cheese-type products” also includes products resembling process cheese, process cheese food, process cheese spread, and process cheese product regardless of whether or not they meet the U.S. Federal Standards of Identity for any of the above products in that they may contain ingredients not specified by such Standards, such as vegetable oil, anhydrous milk fat, or milk protein concentrate, or may/may not meet the compositional requirements of such Standards of Identity. Process cheese-type products also include products having flavor and texture similar to those of a process cheese-type product irrespective of the ingredients or manufacturing steps employed, and irrespective of whether the Standards of Identity have been met. In addition, this invention is applicable to fat-free, reduced-fat or low-fat process cheese-type products.
[0004] U.S. Pat. No. 5,350,595 succinctly describes “pasteurized process cheese” as a product comprising a blend of cheeses to which an emulsifying agent, usually an emulsifying salt, and possibly acids, are added. The mixture is then worked and heated into a homogeneous plastic mass. On cooling, this mass displays the functional and organoleptic properties typical of pasteurized process cheese falling within the U.S. Federal Standards of Identity.
[0005] The term “pasteurized process cheese food” refers to a product which is prepared from the same materials and the same processes used for manufacture of process cheese. However, cheese food generally has dairy ingredients added thereto, such as cream, milk, skimmed milk, whey or any of these from which part of the water has been removed (e.g., concentrated skimmed milk). The moisture level in process cheese food is generally higher than that of process cheese and may be up to about 44%. Fat is present at a level of not less than 23%.
[0006] The term “pasteurized process cheese spread” refers to a product which is similar to cheese food, in the sense that it can contain the indicated dairy ingredients. Process cheese spread, however, may have a moisture level as high as 60%. The minimum fat level for pasteurized process cheese spread is 20%.
[0007] The phrase “high shear” is used often in cheese processing. But, in most cases, the high shear disclosed is much less than the shear rate that is being imposed on the blend of ingredients in the present invention. Although high shear is discussed is prior patents and literature, in most cases, this shear rate is significantly below the shear rate used in this invention. In other cases, high shear rate has been utilized to create a stable emulsion. However, the use of high shear levels as high as disclosed in this invention have not been applied to the manufacture of process cheese-type products; in addition, prior art neither discloses nor contemplates tha application of high shear in combination with increased moisture levels in the manufacture of process cheese-type products.
[0008] Bixby et al., in U.S. Pat. No. 4,444,800, teach the use of high shear agitation to generate a non-cultured, simulated cheese product although the use of high shear was not used to incorporate higher levels of moisture into the product while maintaining the texture, body and eating quality of the resulting cheese.
[0009] U.S. Pat. No. 6,183,804-B1 defines high shear to mean a sufficiently high shear to produce a stable, monodispersed fresh cheese. Again, the application of high shear was not intended to increase the moisture content of the product.
[0010] Renda et al. (1997. Journal of Dairy Science. 80:1901-1907) defines high screw speed, used in the production of low moisture part-skim Mozzarella cheese, as a mixer screw speed of 19 rpm, but there was no attempt to raise the moisture content of the product because of the application of high shear.
[0011] Bell et al. (U.S. Pat. No. 3,922,374) also refers to high shear mixing to create food resembling pasta filata, cheddar, or pasteurized process cheese by using high shear mixing to mix and react calcium hydroxide and fat. The most satisfactory apparatus known to the applicants was the Littleford-Lodige high shear mixing vessels sold by Littelford Brothers, Inc., Cincinnati, Ohio, USA, although no specific shear rate was defined for this process. Moisture increase is not described in the patent.
[0012] In U.S. Pat. No. 5,350,595, Hockenberry et al. define the shear history for a method for continuous manufacture of process cheese-type products. Here, the mechanical shear required to facilitate heat transfer into uncooked cheese particles was required to be at least about 5 reciprocal seconds for a major portion of the process cheese-type formulation, preferably greater than about 70% by weight. If the shear is excessive, it is noted, damage will be done to shear-sensitive components in the finished product. The maximum shear that a minor portion of the process cheese-type formulation, preferably less than about 10% ofthe product, should be subjected to is about 1000 reciprocal seconds; preferably, this portion of the product should be subjected to shear less than about 500 reciprocal seconds. The use of shear coupled with added moisture was not evaluated.
[0013] Wirchansky and De Vito (Canadian Patent 542,392; U.S. Pat. No. 4,749,584) define “high shear blending” to mean conditions sufficient to impart the energy needed to disrupt the cheese curd such that intimate contact is obtained between the disrupted curd and the other ingredients. It was found that a conventional blender, such as a Hobart blender, was sufficient to accomplish this purpose. The resulting product is a low-fat cheese spread. High shear was not used to increase the moisture content of this product, however.
[0014] Laye et al. (U.S. Pat. No. 6,303,160 B1) discuss the application of high shear (via homogenization) of a coarse emulsion to form a fine emulsion with a typical mean particle size of about 1.5 to 5 microns. The result is a high moisture cream cheese with increased firmness. No attempt was made to increase the moisture content of the finished product.
[0015] In addition, the art teaches about the deleterious effects of excessive shear on process cheese-type products. In the book entitled “Process Cheese” by Zehren and Nusbaum, both employees of Schreiber Foods, Inc. of Greenbay, Wis., it is stated that overly vigorous agitation (such as that imparted by the high shear of the inventive process) results in over-emulsification causing an undesirable firm body and often times reduced melt.
[0016] U.S. Pat. No. 5,350,595 cautions that too much agitation during heating results in over-emulsification and a process cheese-type product having undesirable body characteristics. In order for process cheese-type products to have the correct texture, flavor and meltability attributes, they must undergo a specific temperature and shear history. If the shear from agitation is excessive, the fat becomes over-emulsified causing defective texture, i.e., the process cheese-type product becomes too firm and rubbery and it will have restricted melting ability in applications such as hot sandwiches. Hence, the amount of time the process cheese-type product experiences at any given condition of shear and temperature are critical to the finished product attributes.
[0017] In the final report to the Wisconsin Milk Marketing Board (Jaskulka 1994 Development of Pasteurized Blended American Cheese Possessing the Characteristics of Pasteurized Process American Cheese) the effect of high shear on Pasteurized Process Blended American cheese was reported. The use of increased shear rate, via the Stephan cooker, created a product that lacked essential features of acceptable process cheese-type products in that the material produced was difficult to slice and was no longer melt-able.
[0018] Thus, if high shear alone is applied in the production of process cheese-type products, the product becomes too firm, and it does not have sufficient melting characteristics. In order to produce process cheese-type products which are lower in fat and caloric content and more economical to manufacture, it is desirable to increase the content of water in process cheese-type products; however, this has not been made possible by the prior art. If moisture is added to process cheese-type products in a conventional process, the end result is unacceptable in that it fails to retain the organoleptic and performance characteristics of the products being imitated. The resulting product can be hard to slice, is significantly firmer, it melts too much or too quickly, and has an unsuitably soft and gummy consistency. We have found, surprisingly, that the coupling of the two, the addition of moisture and the processing under high shear, provides a unique product.
BRIEF SUMMARY OF THE INVENTION
[0019] The present invention includes a method of increasing moisture level in a cheese or cheese product having a specified moisture level and without substantially changing the organoleptic or physical properties of the cheese or cheese product. The method may include comminuting a selected amount of cheese or cheese product and then adding an incremental amount of additional moisture thereby increasing the overall moisture level above the specified moisture level and subjecting the cheese or cheese product with the additional moisture to a shear rate of at least 500 reciprocal seconds. The resulting increased-moisture process cheese-type product may be used as such or blended with other foods such as conventional moisture process cheese-type products.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The drawing is a flow diagram of the process of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0021] The enclosed flow diagram labeled as FIG. 1 depicts a preferred embodiment of the process of the present invention. As illustrated in FIG. 1, the beginning of the preferred embodiment includes a typical process cheese-type product process. The present invention can be applied to any of the standardized products such as process cheese, process cheese food, process cheese spread, but also to other types of products to which the standards of identity do not apply including imitation cheese products, substitute cheese products, and simulated cheese products. Collectively, all of these will be called process cheese-type products for purposes of this application. One primary difference between each of the above-mentioned products is moisture level. The moisture level increases when comparing process cheese to process cheese food to process cheese spread. As the moisture level is increased, the cheese product takes on different organoleptic and physical characteristics. This invention permits an increase in moisture level while retaining the organoleptic and performance properties of the process cheese-type product as if the additional moisture had not been added. At the same time, increases in moisture content, through the use of high shear, can also be applied to any process cheese-type product whether or not it meets the Standards of Identity and/or is nutritionally equivalent to the product it replaces.
[0022] For the purposes of this application, the products processed under high shear with additional moisture are also referred to as “added moisture cheese products” and include products which meet, or do not meet, the Standards of Identity.
[0023] Referring to FIG. 1, regular natural cheese 10 may be ground up as is typically done in a process cheese process. Depending on the type of product being manufactured, various ingredients are combined together in a blender including preservatives along with concentrated milk proteins, milk fat or oil, water, and sodium chloride (salt). A sample from the blender is analyzed to determine if the mixing goals have been achieved with respect to product composition and uniformity.
[0024] The natural cheese may be ground to a fine particulate size before blending. In actuality, it can be ground to ribbon-like pieces about an inch or so long. This process is referred to as “comminuting” which means to reduce the size of the cheese particles, to reduce in size and minimize the presence of hard rind, and to disrupt the surface membrane of fresh stirred curd to increase the surface area to allow intimate mixing with emulsifiers and other ingredients and to permit uniform heat penetration during the cooking process. Depending on the type of product being manufactured, part or all of the cheese can be replaced by various components including concentrated or unconcentrated milk proteins, milk fat (concentrated or anhydrous), oil, and moisture. The additional moisture of the inventive process can be supplied in the reconstitution of dried dairy ingredients. Although the preferred embodiment illustrated in FIG. 1 uses cheese as the starting material, it will be evident to those skilled in the art that the process is not limited to conventional cheese, but is suitable for imparting desirable characteristics, and increased moisture, to any cheese-like combination of ingredients, and integration into dairy processes. For example, an acid curd or coagulum or concentrated matrix formed by removal of water from milk or a combination of dairy and other food ingredients, such as by diafiltration, ultrafiltration, or reverse osmosis, or finished process cheese-type products can be subjected to the inventive process, to impart desired properties and increased moisture content.
[0025] The mixture after blending is conveyed into a suitable apparatus for heating the mixture. Acid and emulsifying salts may be added and heat and steam are applied to the mix. Preferably, the heating is effected in a conventional processed cheese laydown cooker wherein heating is effected by steam injection. Heating can also be performed in a jacketed mixer, such as a Groen kettle. The temperature and residence time in the cheese cooker are such that microorganisms that could lead to spoilage or food poisoning are killed. In addition, the temperature and residence time are sufficient to inactivate the enzymes found in the natural cheese so that the product does not continue to age. One example of a suitable time and temperature combination is 160° F. for 30 seconds.
[0026] After the cheese cooker, the heated blend is in a flowable condition.
[0027] In one embodiment of the improved process, the heated blend is conveyed to a shearing device as described below. The application of high-shear can be employed as batch, semi-continuous, or continuous processes. Moisture can be added to the heated blend as it is transferred to the shear device.
[0028] One suitable high shear device is a Stephan cooker made by A. Stephan U. Sohne GmbA & Company of Hameln, Germany. The Stephan cooker is used commonly in the process cheese industry although it is not used commonly in the United States. Another suitable high shear device that has been used is a CR Mixer made by Waukesha Cherry-Burrell Products of Delavan, Wis. which has more flexibility than the Stephan cooker with respect to the shear rate applied to the molten cheese product. A third suitable high shear device is the Boston Shear Pump made by Admix, Inc. of Manchester, N.H.
[0029] The Stephan cooker includes a large stainless steel mixing bowl and is a batch-type mixer in which a batch of the mix is placed therein and processed using a selected shear rate, and then taken out. The Stephan cooker used in this invention holds approximately 50 lbs. of mixture and is opened from the top and at its very bottom contains a very sharp two piece agitator with cutting blades. The drive motor to rotate the Cutting blades is mounted below the mixing bowl. The blades pick up the cheese and other ingredients at 1,500 rpm or 3,000 rpm and comminute the material. Steam is injected directly into the mixture of comminuted cheese and ingredients through three stainless steel jets located in the bottom of the bowl. This steam can be used to provide the added moisture of the invention. A mixing baffle, which is operated manually or mechanically, helps rotate the material towards the cutting blades.
[0030] The Stephan cooker can be used for grinding cheese from a big block of cheese, cutting the block into small ribbon-like pieces. The Stephan cooker machine is unique in that it can eliminate the need for a separate grinder to comminute the cheese.
[0031] The CR Mixer, made by Waukesha Cherry Burrell, Delevan, Wis., USA, is of a tube construction and is fed by a positive displacement pump that feeds the mix through a stainless steel liner having a series of pins. As the mix is forced through the pins, shear is generated. The CR Mixer has two sets of pins, one set that is static, and the other set that is moving. The mix exits the stainless steel liner or tube having been processed at a high shear rate.
[0032] The primary feature of the CR Mixer is the ability to make the materials in process pass through a recycle or multi-pass mixing zone of intermeshing pins not once, but many times during their “residence” within the mixer. The number of times the material is returned or recycled to and through the multi-pass zone is controlled by the rotor speed and product consistency. At higher rotor speeds, the material in process is made to circulate and recirculate more times through the multi-pass zone, regardless of the net flow of product. Mixing efficiency can be further enhanced by imposing pressure by a valve in the mixer discharge line.
[0033] The Boston shear pump, manufactured by Admix, Manchester, N.H., USA, is in principal built like a centrifugal pump except instead of an impeller a rotor and stator are used to comminute and transport the material. Shear pumps are also known as wet mills, high shear mixers, and rotor stator homogenizers. In shear pumps, the construction of the rotor and stator may differ which would affect shear rate.
[0034] The additional moisture of the invention can be incorporated into the process cheese-type product after the shear has been applied. After shearing, the molten process cheese-type product is withdrawn from the shearing device and packaged. Packaging may take any one of a number of forms, for example, loaves or jars. Alternatively, the molten process cheese-type product may be formed into slices by distributing the product upon the surface of a cooled rotating chill roll in the form of a thin layer which solidifies into a sheet which is removed from the chilled surface of the roll, cut into strips and subsequently into slices followed by packaging of the sliced process cheese-type product.
[0035] In using these pieces of equipment, it has been discovered that the high shear used in this invention is not necessarily associated with just one instrument, but any one of a number of shear devices could provide the high shear rate needed. As another example, homogenization of process cheese-type products would result in the application of high shear to the product. Therefore, the invention is not dependent on the physical construction of the device but is dependent on particular shear rates experienced by the material. The high shear rate can be calculated from the particular instrument being used.
[0036] The present invention uses shear rate to create a product that was thought not possible to make. It is surprising that utilizing high shear with additional moisture produces a process cheese product (added moisture cheese product or process cheese-type product) that retains its original physical and organoleptic properties.
[0037] To date, high shear has not been used to increase the moisture content of a process cheese-type product while retaining the organoleptic and performance properties of the process cheese-type product as if the additional moisture had not been added. While not wishing to be bound by theory, it is believed that the use of a high shear rate changes the emulsion of the blend of fat and water phases so that the final product holds more moisture while retaining the product characteristics typical of the product that is being imitated (the product before the additional moisture).
[0038] As far as an upper limit of shear rate, the amount of shear applied will depend somewhat on the amount of additional water being placed into the product. If incrementally smaller amounts of moisture are added, then, in general, smaller amounts of shear are needed, and likewise, if a greater amount of moisture is added, then, in general more shear will be required. However, it has also been discovered that the coupling of moisture and high shear to make an acceptable product is a robust process. That is, a relatively wide range of added shear can produce process cheese-type products that retain their original physical and organoleptic properties. The amount of moisture incorporation is directionally a function of shear rate. The minimum amount of shear required for successful product development with this invention is at least approximately 500 reciprocal seconds. Preferably, the shear rate that is necessary for successful product development ranges upward from approximately 1400 reciprocal seconds. A typical amount of additional moisture addition is at least 0.10% on a weight basis. Preferably, 1 to 4% additional moisture is added on a weight basis. However, greater amounts of moisture could also be added.
[0039] Stated otherwise, this invention creates a process cheese-type product which imitates pasteurized process cheese, pasteurized process cheese food, pasteurized process cheese spread, or pasteurized process cheese product since it has the same organoleptic and physical characteristics as the mentioned process cheese-type products but with additional moisture.
[0040] Viscosity agents may be dispersed within the process cheese-type product. Such viscosity agents include gums or starches. However, it is not presently understood whether additional moisture would be bound by the addition of a gum or starch in combination with high shear.
[0041] Some of the organoleptic and physical characteristics of the imitation process cheese produced in accordance with this invention are as follows:
Total Moisture
[0042] The total moisture (water) in the added moisture process cheese-type product produced with this invention ranges from 39.8% to 50.0%. The total moisture is measured according to the Official Methods of Analysis of the Association of Analytical Chemists (AOAC) International, 13th edition, 1980; Section 16.233: “Method I (52)-Official Final Action,” under the heading “Moisture”.
Total Fat
[0043] The added moisture process cheese products made according to this invention have a total fat ranging from 21.00% to 33.00%. The fat is measured by Official Methods of Analysis of the Association of Official Analytical Chemists (AOAC) International, 13th edition, 1980; Section 16.255: “Fat (60)—Official Final Action”.
Melt
[0044] The added moisture process cheese products of this invention have a finished product melt that ranges from a melt test score ‘1’ to ‘6’ according to either one of two melt tests. The first is a Schreiber melt test which includes the use of a circular, 39.5 mm diameter cookie cutter to cut a {fraction (3/16)} inch thick disc of cheese. This disc is placed in a covered 15×100 mm thin wall Pyrex petri dish and heated in a forced draft oven that was preheated to 232° C. (450° F.). The sample was removed after 5 minutes and cooled for 30 minutes at room temperature. The spread of the sample is then measured on a melt test score sheet of 11 concentric rings at an evenly spaced distance of 3.25 mm between each ring from the edge of the cheese product sample. The numerical value given in the melt test score indicates how many rings enclose the melted spread of the sample.
[0045] The other melt test utilized is adopted by the United States Department of Agriculture and is a variation of the Schreiber melt test. The added moisture cheese product is tempered to 45-55° F. A circular disc ¼ inch thick and 1.5 inch in diameter is cutout with a cheese slicer or a cooker cutter and placed in a covered glass petri dish. An oven is preheated to 400° F. and the sample is heated for exactly 10 minutes and removed from the oven. After the sample has cooled, the spread out of the melted cheese is measured on a cheese melting scale, which has 6 concentric rings spread out starting from the edge of the original 1.5 inch diameter cheese disc. The concentric rings are spaced {fraction (3/16)} inch between rings.
Penetrometer
[0046] The added moisture process cheese products have penetration depths of greater than 80 mm using a penetrometer AACC Method 58-14; American Association of Cereal Chemists, consistency-penetration method (10th edition).
Slice/Separation
[0047] The added moisture process cheese product produced in accordance with this invention is sliced freely. The added moisture cheese product did not adhere to the knife and fell away from the knife and was not sticky nor did it show tearing or mealiness. The procedure used is described on pages 302-304 of “Process Cheese” by Zehren and Nusbaum, 1992. Ideally, a slicer blade as in a commercial reciprocating carriage having a spinning disc is used.
[0048] Although the present invention has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention. | A method increases moisture level to produce a process cheese-type product with additional moisture without substantially changing organoleptic or physical properties of the cheese of cheese product. The method includes comminuting the cheese or cheese product and then adding an incremental amount of additional moisture thereby increasing the overall moisture level above the original moisture level of the cheese or cheese product while subjecting the cheese or cheese product to a shear rate of at least 500 reciprocal seconds. | 0 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The subject invention generally pertains to refrigerant systems and more specifically to a refrigerant circuit that offers a reheat mode of operation.
[0003] 2. Description of Related Art
[0004] Conventional refrigeration systems comprising a compressor, a condenser, an expansion valve and an evaporator can be used to meet the sensible and latent cooling demands of a room or area in a building when the room temperature is appreciably above a target temperature. In some circumstances, however, high humidity can leave a room feeling uncomfortable even though the room temperature might be at or even below the target temperature. Although further cooling of the room can reduce the humidity, the additional cooling can make the air in the room feel cold and dank.
[0005] To avoid this problem, many refrigerant systems include a reheat mode where a heater downstream of the evaporator raises the temperature of the supply air after the evaporator cools the air to reduce the humidity. Such systems can effectively address the latent cooling or dehumidifying demand without subcooling the room. Although the reheat mode can be provided by electric heat or combustion, the system can be less expensive to operate if the reheat is provided by the refrigerant circuit itself. In some cases, for instance, the compressor discharges relatively hot refrigerant gas into an additional heat exchanger that reheats the air that was previously cooled by the evaporator.
[0006] Using an additional heat exchanger in such a manner, however, can create a problem regarding the system's refrigerant charge. Air conditioning systems typically require less refrigerant during a reheat mode than during a cooling-only mode. Unless the system has some means for adjusting its refrigerant charge, the system might have an excessive amount of refrigerant during the reheat mode or an insufficient supply during the cooling mode. Thus, the system's efficiency might suffer in the cooling and/or reheat mode.
[0007] Previous systems addressing reheat and charge control include those shown in U.S. Pat. No. 6,122,923 to Sullivan; U.S. Pat. No. 6,170,271 to Sullivan; U.S. Pat. No. 6,381,970 to Eber et al.; and, U.S. Pat. No. 6,612,119 to Eber et al.; all of which are commonly assigned to the assignee of the present invention and all of which are hereby incorporated by reference. Although some systems include a liquid receiver for storing excess refrigerant during the reheat mode, such systems can be expensive due to the cost of the added receiver and associated control valves. Consequently, a need exists for a simpler, more cost effective refrigerant reheat system.
SUMMARY OF THE INVENTION
[0008] It is an object of the present invention to provide a simpler, more cost effective refrigerant system with a reheat mode.
[0009] Another object of some embodiments is to adjust a refrigerant system's effective charge without using a liquid receiver dedicated for that purpose.
[0010] Another object of some embodiments is to monitor and control the amount of subcooling occurring in a reheat coil.
[0011] Another object of some embodiments is to adjust a refrigerant system's effective charge by using the auxiliary side connector of an expansion valve, wherein the auxiliary side connector is downstream of the valve's flow restriction and upstream of the valve's multi-line flow distributor.
[0012] Another object of some embodiments is to control the amount of subcooling in a reheat coil by adjusting a system's effective refrigerant charge.
[0013] Another object of some embodiments is to determine the level of subcooling in a reheat coil by sensing the temperature of the refrigerant leaving the coil and sensing the temperature of the refrigerant at a strategic intermediate point within the coil.
[0014] Another object of some embodiments is to switch the operation of a refrigerant system between a cooling-only mode and a reheat mode by selectively deactivating a main condenser or a reheat coil.
[0015] Another object of some embodiments is to store liquid refrigerant in an inactive condenser during a reheat mode.
[0016] Another object of some embodiments is to use a plurality of simple check valves to minimize the use of solenoid valves and other externally actuated control valves in switching a refrigerant system between a cooling-only mode and a reheat mode.
[0017] Another object of some embodiments is to use a combination evaporator and reheat coil that share a common set of heat exchanger fins rather than using two individual heat exchangers for cooling and reheat functions.
[0018] Another object of some embodiments is to reverse a refrigerant's direction of flow through a reheat portion of a heat exchanger while leaving the refrigerant's direction of flow through an evaporator the unchanged.
[0019] Another object of some embodiments is to deactivate a condenser during a reheat mode of operation.
[0020] Another object of some embodiments is to use a reheat coil in both a reheat mode and a cooling-only mode, wherein the reheat coil provides heat in the reheat mode and provides cooling in the cooling-only mode.
[0021] One or more of these and/or other objects of the invention are provided by a refrigerant system that is selectively operable in cooling mode and a reheat mode, wherein a main condenser is deactivated in the reheat mode and in some cases excess liquid refrigerant is stored therein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a schematic view of a refrigerant system selectively operating in a cooling mode.
[0023] FIG. 2 is a schematic view of the refrigerant system of FIG. 1 but shown operating in a reheat mode.
[0024] FIG. 3 is a schematic view of another refrigerant system selectively operating in a normal cooling mode.
[0025] FIG. 4 is a schematic view of the refrigerant system of FIG. 3 but shown operating in a reheat mode.
[0026] FIG. 5 is a schematic view of another refrigerant system selectively operating in a normal cooling mode.
[0027] FIG. 6 is a schematic view of the refrigerant system of FIG. 5 but shown operating in a reheat mode.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0028] A refrigerant system 10 includes a directional valve 12 that can configure system 10 in a cooling mode as shown in FIG. 1 or a reheat mode as shown in FIG. 2 . System 10 generally operates in the cooling mode to meet sensible and latent cooling demands of a room or area in a building when the room temperature is appreciably above a target temperature. The reheat mode is typically used to address the latent cooling or dehumidifying demand when the room temperature is near or below the target temperature.
[0029] For the embodiment of FIGS. 1 and 2 , system 10 comprises a compressor 14 , a condenser 16 , an evaporator 18 , a reheat coil 20 , an expansion device 22 (e.g., thermal expansion valve, electronic expansion valve, orifice, capillary, etc.), and various valves that may include one or more of the following: a check valve 24 , a check valve 26 , a solenoid valve 28 and a solenoid valve 30 .
[0030] In the cooling mode, directional valve 12 directs relatively high-pressure, high-temperature refrigerant discharged from compressor 14 to condenser 16 , and reheat coil 20 is generally inactive. An outdoor fan 32 can be energized to force outside air 34 across condenser 16 so that air 34 cools and condenses the refrigerant in condenser 16 . From condenser 16 , the refrigerant flows sequentially through check valve 24 and expansion device 22 . Upon passing through expansion device 22 , the refrigerant cools by expansion before entering evaporator 18 . The refrigerant flowing through evaporator 18 can cool a stream of air 36 that an indoor fan 38 forces across evaporator 18 and the currently inactive reheat coil 20 . After passing through evaporator 18 , the refrigerant returns to compressor 14 to perpetuate the cooling cycle.
[0031] In the cooling mode, check valve 26 inhibits liquid refrigerant from bypassing expansion device 22 thereby preventing the flooding of the inactive reheat coil 20 . Solenoid valve 28 is closed to inhibit refrigerant from bypassing check valve 24 and expansion device 22 . Solenoid valve 30 is normally kept open continuously. When open, solenoid valve 30 can convey refrigerant from reheat coil 20 to a point 40 between expansion valve 22 and evaporator 18 .
[0032] In a currently preferred embodiment, point 40 is an auxiliary side port of expansion device 22 , wherein expansion device 22 in this case comprises a Sporlan expansion valve p/n OZE-25-ZGA, a Sporlan multi-line distributor p/n 1117-13-¼″-C17, and a Sporlan auxiliary side port connector p/n ASC-11-7. Sporlan is based in Washington, Missouri and is a division of Parker Hannifin Corporation. Point 40 is downstream of Sporlan expansion valve p/n OZE-25-ZGA and upstream of Sporlan multi-line distributor p/n 1117-13-¼″-C17. Although the Sporlan assembly is currently preferred, other examples of expansion device 22 are well within the scope of the invention.
[0033] In the reheat mode, as shown in FIG. 2 , condenser 16 is generally inactive, and directional valve 12 directs relatively high-pressure, high-temperature refrigerant from compressor 14 to reheat coil 20 , thereby heating coil 20 . From reheat coil 20 , the refrigerant flows sequentially through check valve 26 and expansion device 22 . Upon passing through expansion device 22 , the refrigerant cools by expansion before entering evaporator 18 , thereby cooling evaporator 18 . To remove latent heat from air stream 36 , air stream 36 is cooled by evaporator 18 and heated by reheat coil 20 . After passing through evaporator 18 , the refrigerant returns to compressor 14 to perpetuate the reheat cycle.
[0034] During the reheat mode, check valve 24 inhibits liquid refrigerant from backflowing into inactive condenser 16 . Directional valve 12 and solenoid valves 28 and 30 are controlled to maintain a desired level of subcooling in reheat coil 20 . To do this, a system controller 42 determines and monitors the level of subcooling in reheat coil 20 and compares the level to an established subcooling target. The subcooling target can be a predetermined range of acceptable values, wherein the range lies between certain upper and lower limits.
[0035] In some embodiments, controller 42 (e.g., computer, programmable logic controller, or suitable electrical circuit) determines the level of subcooling in reheat coil 20 based on the difference between a first refrigerant temperature and a second refrigerant temperature, wherein a first sensor 44 monitors the first temperature at a first point that is between an inlet 46 and an outlet 48 of reheat coil 20 , and a second sensor 50 monitors the second temperature at a second point that is downstream of the first point. The location of the first point can be about twice as far from inlet 46 than from outlet 48 so that the first temperature reflects the refrigerant's saturated temperature within reheat coil 20 . The second point is preferably near outlet 48 so that the difference between the first and second temperatures, as determined by controller 42 , reflects the level of subcooling in reheat coil 20 .
[0036] If the level of subcooling is substantially at the subcooling target (e.g., within the predetermined acceptable range), controller 42 leaves solenoid valves 28 and 30 closed. Valve 28 being closed generally traps a substantially fixed amount of liquid refrigerant within condenser 16 , and valve 30 being closed prevents subcooled liquid refrigerant within reheat coil 20 from bypassing expansion device 22 and rushing into evaporator 18 .
[0037] If the level of subcooling is below the subcooling target, controller 42 opens solenoid valve 28 while leaving solenoid valve 30 closed. This allows solenoid valve 28 to convey liquid refrigerant from condenser 16 to evaporator 18 and ultimately to reheat coil 20 as compressor 14 forces gaseous refrigerant from evaporator 18 to reheat coil 20 . Once the subcooling level increases to the subcooling target, controller 42 closes valve 28 while valve 30 is already closed.
[0038] If the level of subcooling is above the subcooling target, controller 42 temporarily shifts directional valve 12 to its position of FIG. 1 and opens solenoid valve 30 . Valve 30 being open conveys liquid refrigerant from reheat coil 20 to the inlet of evaporator 18 , and directional valve 12 allows compressor 14 to force refrigerant from evaporator 18 to condenser 16 , thus effectively transferring refrigerant from reheat coil 20 to condenser 16 . After the subcooling level decreases to the subcooling target, controller 42 shifts directional valve 12 to its position of FIG. 2 and closes valve 30 while valve 28 is already closed.
[0039] To carry out the operations just described with respect to the cooling and reheat modes, controller 42 can provide one or more various output signals 52 in response to one or more various input signals 54 . Examples of inputs 54 might include, but are not limited to, an input 54 a from temperature sensor 44 and an input 54 b from temperature sensor 50 . Examples of outputs 52 might include, but are not limited to, an output 52 a to control fan 32 , an output 52 b to control fan 38 , an output 52 c to control compressor 14 , an output 52 d to control directional valve 12 , an output 52 e to control solenoid valve 28 , and an output 52 f to control solenoid valve 30 . In cases where expansion device 22 is an electronic expansion valve, controller 42 controls device 22 via an output signal 52 g in response to a leaving refrigerant evaporator temperature input 54 c from a temperature sensor 56 . In cases where expansion device 22 is a thermal expansion valve, signal 54 c might control expansion device 22 directly. If expansion device 22 has a fixed flow restriction as opposed to having an adjustable one, signal 52 g might be eliminated.
[0040] In an alternate embodiment, shown in FIGS. 3 and 4 , a refrigerant system 58 comprises compressor 14 , condenser 16 , evaporator 18 , reheat coil 20 , expansion device 22 , a directional valve 60 , and three check valves 62 , 64 and 66 . For illustration, expansion device 22 is shown as a thermal expansion valve being controlled by a conventional temperature bulb 56 ′ on the suction line leading to compressor 14 ; however, other types of expansion devices (e.g., electronic expansion valve, fixed orifice, capillary, etc.) are well within the scope of the invention. Evaporator 18 and reheat coil 20 are connected in parallel flow relationship with respect to the flow of refrigerant and are disposed in series flow relationship with respect to air stream 36 . Although evaporator 18 and reheat coil 20 are schematically illustrated as two separate heat exchangers, they can actually be a single unit with multiple rows of refrigerant conduit sharing common heat transfer fins. Directional valve 60 determines whether system 58 is operating in a cooling mode, as shown in FIG. 3 , or operating in a reheat mode, as shown in FIG. 4 .
[0041] In the cooling mode, directional valve 60 directs refrigerant from compressor 14 to condenser 16 where air 34 cools and condenses the refrigerant therein. From condenser 16 , the refrigerant flows sequentially through check valve 62 (first check valve) and expansion device 22 . Upon passing through expansion device 22 , the refrigerant cools by expansion. After passing through expansion device 22 , a first portion of the cooled refrigerant enters evaporator 18 while a second portion passes through check valve 64 (second check valve) to enter reheat coil 20 now functioning as a supplemental evaporator. Check valve 66 (third check valve) prevents liquid refrigerant leaving condenser 16 from bypassing expansion device 22 . The refrigerant in evaporator 18 and reheat coil 20 cool air stream 36 . After passing through their respective heat exchangers, both portions of the refrigerant return to the suction side of compressor 14 to perpetuate the cooling cycle.
[0042] In the reheat mode, shown in FIG. 4 , condenser 16 is generally inactive, and directional valve 60 directs refrigerant from compressor 14 to reheat coil 20 , thereby heating coil 20 . From reheat coil 20 , the refrigerant flows sequentially through check valve 66 and expansion device 22 . Check valve 62 prevents liquid refrigerant from backflowing into condenser 16 , and check valve 64 prevents liquid refrigerant leaving reheat coil 20 from bypassing expansion device 22 and flowing directly into evaporator 18 . Upon passing through expansion device 22 , the refrigerant cools by expansion before entering evaporator 18 , thereby cooling evaporator 18 . To remove latent heat from air stream 36 , air stream 36 is cooled by evaporator 18 and heated by reheat coil 20 . After passing through evaporator 18 , the refrigerant returns to compressor 14 to perpetuate the reheat cycle.
[0043] In the cooling mode, the refrigerant flows in a forward direction through reheat coil 20 , but in the reheat mode, the refrigerant flows in a reverse direction through reheat coil 20 . The refrigerant passing through evaporator 18 , however, flows in the same predetermined direction regardless of whether system 58 is operating in the cooling or reheat mode.
[0044] In another embodiment, shown in FIGS. 5 and 6 , a refrigerant system 68 comprises compressor 14 , condenser 16 , evaporator 18 , reheat coil 20 , expansion device 22 , directional valve 60 , a solenoid valve 70 , and three check valves 62 , 64 and 66 . Evaporator 18 and reheat coil 20 are connected in series flow relationship with respect to the flow of refrigerant and air stream 36 . Directional valve 60 determines whether system 68 is operating in a cooling mode, as shown in FIG. 5 , or operating in a reheat mode, as shown in FIG. 6 .
[0045] In the cooling mode, directional valve 60 directs refrigerant from compressor 14 to condenser 16 where air 34 cools and condenses the refrigerant therein. From condenser 16 , the refrigerant flows sequentially through check valve 62 and expansion device 22 . Upon passing through expansion device 22 , the refrigerant cools by expansion. After passing through expansion device 22 , the cooled refrigerant passes through evaporator 18 . From evaporator 18 , check valve 64 conveys the refrigerant through reheat coil 20 (functioning as a supplemental evaporator). Solenoid valve 70 is closed to prevent refrigerant leaving evaporator 18 from bypassing reheat coil 20 , and check valve 66 prevents liquid refrigerant leaving condenser 16 from bypassing expansion device 22 . The refrigerant in evaporator 18 and reheat coil 20 cool air stream 36 . After passing sequentially through evaporator 18 and reheat coil 20 , the refrigerant returns to the suction side of compressor 14 to perpetuate the cooling cycle.
[0046] In the reheat mode, shown in FIG. 6 , condenser 16 is generally inactive, solenoid valve 70 is open, and directional valve 60 directs refrigerant from compressor 14 to reheat coil 20 , thereby heating coil 20 . From reheat coil 20 , the refrigerant flows sequentially through check valve 66 and expansion device 22 . Check valve 62 prevents liquid refrigerant from backflowing into condenser 16 , and check valve 64 prevents liquid refrigerant leaving reheat coil 20 from bypassing expansion device 22 and evaporator 18 . Upon passing through expansion device 22 , the refrigerant cools by expansion before entering evaporator 18 , thereby cooling evaporator 18 . To remove latent heat from air stream 36 , air stream 36 is cooled by evaporator 18 and heated by reheat coil 20 . After passing through evaporator 18 , open solenoid valve 70 conveys the refrigerant back to compressor 14 to perpetuate the reheat cycle.
[0047] In the cooling mode, the refrigerant flows in a forward direction through reheat coil 20 , but in the reheat mode, the refrigerant flows in a reverse direction through reheat coil 20 . The refrigerant passing through evaporator 18 , however, flows in the same predetermined direction regardless of whether system 68 is operating in the cooling or reheat mode.
[0048] Although the invention is described with respect to a preferred embodiment, modifications thereto will be apparent to those of ordinary skill in the art. The scope of the invention, therefore, is to be determined by reference to the following claims. | A refrigerant system for cooling a comfort zone is selectively operable in a cooling-only mode and a reheat mode. The system operates in the cooling mode to meet sensible and latent cooling demands of a room or area in a building when the room temperature is appreciably above a target temperature. The reheat mode is for addressing the latent cooling or dehumidifying demand when the room temperature is near or below the target temperature. In some embodiments, a generally inactive condenser stores excess refrigerant during the reheat mode, thereby avoiding the need for a separate liquid refrigerant receiver. To maintain a desired level of subcooling in the reheat coil, refrigerant can be transferred accordingly between the inactive condenser and the reheat coil. In some embodiments, the system's evaporator and reheat coil can be connected in a series or parallel flow relationship. | 5 |
BACKGROUND
A gas turbine engine typically includes a fan section, a compressor section, a combustor section, a turbine section, and in some configurations an augmenter section. A liner extending aft of the turbine section typically referred to as an exhaust or augmenter liner includes an inner liner exposed to hot exhaust gases. The inner liner is typically spaced from an outer structure with a plurality of hanger assemblies. The hanger assemblies are required to accommodate misalignment, complex shapes, large thermal growth differentials, significant pressure loads and high temperatures. Moreover, the hangers are positioned within a confined physical envelope that is difficult to access while accommodating relative movement within several planes simultaneously.
Accordingly, it is desirable to design and develop a reduced cost hanger that performs as desired in the harsh environment of the exhaust duct while also simplifying assembly and reducing cost.
SUMMARY
According to an embodiment disclosed herein, a hanger assembly for use between a first duct and a second duct includes a flexible leaf spring having a body and a leg, a locking member for attaching the leg to the first duct, and a mounting member for attaching the body to the second duct.
According to any prior embodiment disclosed herein, the body includes a circular portion extending therefrom.
According to any prior embodiment disclosed herein, the body has an opening therein cooperating with a stud extending from the second duct.
According to any prior embodiment disclosed herein, a first portion of the leg extends from the body at an inner obtuse angle.
According to any prior embodiment disclosed herein, a second portion of the leg extends from the first portion of the leg at an inner acute angle.
According to any prior embodiment disclosed herein, a third portion of the leg extends from the second portion of the leg at an outer acute angle.
According to any prior embodiment disclosed herein, the locking member includes a cover, a first flange formed upon the cover and extending from cover towards the body and a second flange extending from the first flange at an outer obtuse angle, wherein the first flange and the second flange capture the leg.
According to any prior embodiment disclosed herein, the leg has a portion disposed at an acute angle, such portion captured by the first flange and the second flange wherein the acute angle and the obtuse angle are complementary to each other.
According to any prior embodiment disclosed herein, the second flange is wider than the portion.
According to a further embodiment disclosed herein, a gas turbine engine includes a fan section including a plurality of fan blades rotatable about an axis; a compressor section in communication with the fan section; a combustor in fluid communication with the compressor section; a turbine section in fluid communication with the combustor and driving the fan section and the compressor section; and an exhaust liner aft of the turbine section, the exhaust liner including a liner defining an inner surface exposed to exhaust gases, a duct spaced radially outward of the liner; and a hanger assembly supporting the liner relative to the duct, the hanger assembly including a flexible leaf spring having a body and a leg, a locking member attaching the leg to the duct; and a mounting member attaching the body to the liner.
According to any prior embodiment disclosed herein, a first portion of the leg extends from the body at an inner obtuse angle, wherein a second portion of the leg extends from the first portion of the leg at an inner acute angle and wherein a third portion of the leg extends from the second portion of the leg at an outer acute angle.
According to any prior embodiment disclosed herein, the locking member includes a cover disposed outside of the casing, a first flange formed upon the cover and extending from cover towards the body and a second flange extending from the first flange at an outer obtuse angle, wherein the first flange and the second flange capture the leg.
According to any prior embodiment disclosed herein, the leg has a portion disposed at an acute angle, such portion captured by the first flange and the second flange wherein the acute angle and the obtuse angle are complementary to each other.
According to a still further embodiment disclosed herein, a method of supporting a liner of a gas turbine engine includes the steps of providing a flexible leaf spring having a body and a leg, a locking member for attaching the leg to the first duct and a mounting member for attaching the body to the second duct, providing an opening in the first duct, and inserting the leaf spring through the opening.
According to any prior embodiment disclosed herein, the method includes the further step of arranging the leaf spring so that a thickness of the leaf spring is parallel to flow passing between the first and second ducts.
According to any prior embodiment disclosed herein, the method includes the further step of attaching the body of the leaf spring to a stud extending from the second duct.
According to any prior embodiment disclosed herein, the method includes the further step of inserting the lock member through the opening, and rotating the lock member to capture the leg between the lock member and the first duct.
According to any prior embodiment disclosed herein, the method includes the further step of providing a cover for covering the opening over the opening, the cover having the lock member attaching thereto, and putting the cover on the first duct such that the lock member extends through the opening without engaging the leg.
According to any prior embodiment disclosed herein, the method includes the further step of rotating the cover and the lock member to lock the leg between the lock member and the first duct.
These and other features disclosed herein can be best understood from the following specification and drawings, the following of which is a brief description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a sectional view of a gas turbine engine incorporating an embodiment of a leaf spring hanger shown herein.
FIG. 2 shows a side view leaf spring hanger embodiment for use in then engine of FIG. 1 .
FIG. 3 shows a perspective view of a cover for use as a part of the hanger assembly as shown in FIG. 2 .
FIG. 4 shows a perspective view of the leaf spring assembly as used in FIG. 2 .
FIG. 5 shows a sectional, perspective view of the leaf spring hanger assembly of FIG. 4 .
DETAILED DESCRIPTION
Referring to FIG. 1 , a gas turbine engine 10 includes a fan section 12 , a compressor section 14 , a combustor section 16 , and a turbine section 18 . Air entering into the fan section 12 is initially compressed and fed to the compressor section 14 . In the compressor section 14 , the incoming air from the fan section 12 is further compressed and communicated to the combustor section 16 . In the combustor section 16 , the compressed air is mixed with gas and ignited to generate a hot exhaust stream 28 . The hot exhaust stream 28 is expanded through the turbine section 18 to drive the fan section 12 and the compressor section 14 . In this example, the gas turbine engine 10 includes an augmenter section 20 where additional fuel can be mixed with the exhaust gasses 28 and ignited to generate additional thrust. The exhaust gasses 28 flow from the turbine section 18 and the augmenter section 20 through an exhaust liner assembly 22 .
The example exhaust liner assembly 22 includes a liner 24 that defines an inner surface exposed to the hot exhaust gasses 28 . The liner 24 (e.g., a first duct) is supported by a duct 26 (e.g., a second duct) disposed radially outward of the liner 24 . An annular space 30 is disposed between the liner 24 and the duct 26 for a cooling airflow. The example exhaust liner assembly 22 includes a first section 32 , a second section 34 , and third section 36 . Each of the first, second and third sections 32 , 34 , 36 are movable relative to each other to provide a thrust vectoring function. As appreciated, although the gas turbine engine 10 is disclosed and described by way of example and other configurations and architectures of gas turbine engines are within the contemplation of this disclosure and would benefit from the disclosures within this application.
Referring to FIG. 2 a leaf spring hanger assembly 95 is shown. A casing/outer duct 26 / 100 has a major opening 105 (see also FIGS. 4 and 5 ) and a plurality of bolt holes 110 as will be discussed herein (See FIG. 4 ).
Liner/inner duct 24 / 115 is disposed within the casing/outer duct 26 / 100 . A plurality of studs 120 are fixedly attached to the liner 115 as are known in the art (see FIGS. 2 and 5 ). A leaf spring 125 has a flat body 130 that touches the liner 115 along a length D of the flat body 130 . The flat body 130 has an orifice 135 extending therethrough (see also FIG. 5 ) for extending around the stud 120 protruding from the liner 115 . The flat body 130 has a portion 140 ( FIG. 5 ), which may be circular, that extends around the central opening orifice 135 to provide load support of the flat body along a greater surface area of the liner 115 . The flat body 130 has a pair of integrally formed legs 145 . The legs 145 have a first bend portion 150 that forms an inner side obtuse angle α relative to the flat body portion 130 . The legs extend away from the first bend portion 150 to the second bend portion 155 that forms an inner side acute angle β, and extend to a third bend portion 160 that forms an outer side acute angle γ. The end portion 165 of each leg 145 is parallel to the casing 100 and roughly parallel to the flat body portion 130 .
The legs 145 have a first portion 147 between the first bend portion 150 and the second bend portion 155 , a second portion 153 between the second bend portion 155 and the third bend portion 160 and end portion 165 . The wear areas 201 that extend from second portion 153 around the third bend 160 to the third leg may be coated with a coating 207 to minimize wear on the rubbing surfaces. Alternatively portions of the first flange 190 , the second flange 195 and the casing 100 or combinations thereof may also be coated with a coating 207 .
Referring now to FIG. 3 , cover 170 has a roughly elliptical body 175 having a pair of apertures 180 that align with holes 110 in the casing 100 for attachment thereto. Each of a pair of locking tabs 185 have a first flange 190 perpendicular to the body 175 and a second flange 195 extending at an outer obtuse angle Δ from the first flange 190 . The second flanges 195 extend away from each other and the first flanges 190 are in parallel to each other. The second flanges have an outer end 205 that fit within major opening 105 (see FIG. 4 ). The outer ends 205 may be slightly smaller than a diameter of the major opening 105 to allow insertion of the cover by tilting one side of the cover 170 , inserting one of the first flanges 190 on the tilted side into the major opening 105 until the casing 100 engages the first flange 190 and then tilting another side of the cover 170 and its other flange 190 through the major opening 105 .
In order to construct the hanger assembly as seen in FIGS. 4 and 5 , leaf spring 125 , which is flexible, is manipulated and compressed so its body 130 and its legs 145 fits through the major opening 105 . The orifice 135 of the leaf spring 125 is inserted over the stud 120 and then secured thereto by a nut 210 . The width of the leaf spring is arranged parallel to the flow 116 so that the narrow width of the leaf spring 125 minimizes obstructions to flow 116 passing between the casing 100 and the liner 115 . The width W 1 of the first and second flanges 190 , 195 is greater than the width W 2 of the leaf spring 125 to accommodate any axial movement of the casing 100 relative to the liner 115 that would tend to move the leaf spring axially relative to the casing 100 so the leaf spring remains locked relative to the casing 100 .
After the leaf spring 125 is secured to the liner 115 , cover 170 is inserted into the major opening 105 so that the locking tabs 185 do not interfere with the leaf spring 125 (see FIG. 4 ). Cover 170 is then rotated so that the apertures 180 align with the holes 110 and the locking tabs 185 are in parallel with the leaf spring 125 such that the third bend 160 of each leg is disposed between each locking tab 185 and the casing 100 . There may be a gap G between the legs 145 and the locking tabs 185 to allow for relative motion between the parts. The angle γ and the angle Δ are complementary (see FIG. 2 ) so that the third bend portion 160 fits behind the locking tabs at an angle Δ such that the angle Δ and the angle γ sum up to approximately 180°. Because the major opening 105 is completely covered by the cover 170 there is minimal leakage between the cover and the casing 100 . There are very few parts involved with this assembly.
Thermal movement between the liner and the case is provided in all directions. The leaf spring 125 acts in tension and compression. The leaf spring 125 hardness and flexibility can be tailored for required loads and because of the tolerances built into the system no shimming or rigging is required.
Although an embodiment of this invention has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention. | A hanger assembly for use between a first duct and a second duct has a flexible leaf spring having a body and a leg, a locking member for attaching the leg to the first duct, and a mounting member for attaching the body to the second duct. | 5 |
BACKGROUND OF THE INVENTION
The present invention deals with the improvements introduced in a pneumatic propulsion system for freight and/or passenger vehicles, which aim to enhance its constructive and functional features, ensuring this system a highly favorable performance in the transportation of freight and/or passengers.
The state-of-the-art, taken as reference for the insertion of the improvements described in this report, is represented by the pneumatic propulsion system for freight and/or passenger vehicles according to the Brazil Patent of Invention nbr. 7703372 deposited on the 25 th of May of 1977 characterized by comprising a tube having a longitudinal slit with a sealing system, a pylon, attaching a propelling fin assembly that travels in the tube to the frame of a vehicle that is supported by the tube, said pylon sliding through the longitudinal slit, propulsion being effected by means of a high-speed airflow acting on the blocking surface of the propelling fin moving it and consequently setting the vehicle into motion on devices adequate to support such motion, said airflow being generated by stationary air sources positioned outside the vehicle. Said system vehicle is provided with brakes that act directly on the motion-support devices and its tube is outfitted with conduits for telephone lines. The pneumatic system so described is characterized by pneumatic propulsion of vehicles from stationary units, and the system objectives are as follows: to provide an urban transportation system dimensioned to cater for today's and future needs; to make compatible under one unique concept optimum features for vehicles, trackway and terminals, to achieve significant advances in economics, speed, regularity, comfort and safety at low cost.
Also known as state-of-the-art are first improvements introduced in the pneumatic transportation system for freight or passenger vehicles in accordance with the Brazil Patent of Invention nbr. 7906255 deposited on the 28th of Sept. of 1979, characterized by having a propulsion duct which besides channelling air for vehicle propulsion additionally provides the structure required to install an elevated trackway, that is, the structure of the propulsion duct itself embodies an elevated trackway with integrally attached rails, thereby doing away with any other rail support structures, except for structures spaced at intervals wide enough so not as to interface with surface traffic that support or hold the entire structure above ground. A part of said system provisions are made to seal the longitudinal slit in the duct, when suction is applied to the duct, said differential pressure acting on a flexible seal and pressing it against a stop, allowing at same time passage of the propulsion pylon by mechanical displacement of the elastic flap, said elastic flap also allowing for sealing in overpressure, a pressure relief system also being provided. Said system incorporates a flow alternator close to each air blower unit which, in combination with a flow control valve provides control over any airflow condition in the duct, thus determining vehicle movements by remote control. Said system comprises a set of valves at each terminal arranged to ensure means of control for a safety system that guarantees positive separation of vehicles under any circumstances, overall system being under control of one operator and/or an automatic control system located at each station. The perfected automatic propulsion system for transportation of cargo and/or passengers as described above and which is characterized by pneumatic propulsion of vehicles from stationary airflow generating units, has the following basic objectives:
1. Provide an elevated trackway for transportation vehicle traffic, said way having least possible dimensions for a given transport capacity, aiming at low building and installation costs, and minimum environmental impact.
2. To achieve extremely light and simple transportation vehicles, free of any propulsion equipments, the low weight of which will require little energy for accelerating and braking and impose a low stress level to the trackway, aiming also at simple construction and maintenance, low operating costs and high reliability.
3. Provide a vehicle propulsion system that is stationary, aiming at low vehicle weight, low maintenance costs, high reliability, minimum environmental pollution.
4. Provide a pneumatic propulsion system that does not engage vehicular wheels, effecting vehicle traction by means of a device that is independent of the wheels, with the objective of overcoming the limitations imposed by wheel/rail systems on the performance of rail transport vehicles. And, lastly,
5. To effect the integration of all elements in a freight and/or passenger transportation system on an elevated way, silent, non-pollutant, adequate for installation over streets of urban centers, with low investment, low operating costs, high reliability and safety and high transport capacity.
SUMMARY OF THE INVENTION
The present invention refers to a series of improvements introduced in a pneumatic propulsion system for cargo and/or passenger vehicles, characterized basically by having a propulsion duct that, besides channelling air for vehicle propulsion provides the structure necessary to install an elevated trackway transportation system, that is, the structure of the propulsion duct itself embodies an elevated trackway with integrally attached rails, thereby doing away with any other rail support structures, except for structures spaced at intervals wide enough so as not to interfere with surface traffic, that support or hold the entire structure above ground. The invention, object of the present descriptive report deals, firstly, with a specific constructive form for the propulsion duct structure, characterized basically by pre-formed concrete or steel structural elements which, once assembled form end-supported beams of great strength and lightness to support the system trackway said beams functioning at the same time as air propulsion ducts and embodying structural provisions for installation of air flow control valves and/or secondary air ducts. Upon system installation the trackway is installed by first erecting support pillars at regular spacing, on which the ends of the modular beams are then laid and aligned, that constitute the support base for the rails. Sealing at beam butt ends forms the air duct for system propulsion. Modular construction of beams and pillars ensures pre-fabrication of all elements of the trackway of this transportation system in a plant and/or a remote building site, with quick erection on-site, incurring in minimal traffic disruption.
Another important feature of this invention is the improved device to seal the longitudinal slit in the propulsion air duct, the objective of said seal being to contain the air differential pressure between the duct interior and the atmosphere as generated by airflow generator units, while providing passage to the propulsion plate attaching mast with minimum losses. Said device consists basically of two flexible flaps attached to opposite faces of the duct slit, which are superimposed, allowing for passage of the attaching mast or pylon by mechanical displacement of the flexible flaps, while at the same time a pressure differential, either positive or negative, between air duct and the atmosphere will press the seal flaps tightly against each other, providing for efficient duct sealing. In the pneumatic propulsion system dealt with in the present invention, the vehicle is controlled by regulating the airflow in the propulsion air duct by use of butterfly control valves associated with our airflow generator unit, which, by their position, determine the direction, speed and differential pressure of airflow in the duct within the full performance range of pressure and flow of that air generator unit. A set of four valves located at each air unit and interconnecting its suction and discharge ports to the propulsion air duct and the atmosphere provided, by means of a combined operation, the desired airflow control with high reliability and safety.
The airflow regulation system by means of control valves presented in this invention has its actuation effected by pneumatic cylinders, which may take up several positions and are electrically controlled. By use of electronic logic circuits their command is effected throughout the position combinations required for vehicle operation in its full performance range in both directions, command being exerted by the operator from a remote position close or away from a passenger terminal, by means of a single electric selector switch, or, in case of automatic system operation, said logic circuits instead of being controlled manually will be controlled electrically by an interface module with a control microprocessor.
This invention also presents a design for duct shutoff valves that are installed to the propulsion duct with the function of interrupting airflow at that point, whenever required in order to, in combination with similar valves, delimit a specific propulsion air circuit, said shutoff valve being of simple design while providing reliable and safe operation.
The present invention also provides a means to determine position and speed of the vehicle, while the same travels over the trackway, giving the operator at his operation stand continuous information about these parameters and, if required, feeding information to a control microprocessor. For this purpose, the trackway is outfitted at regular intervals with "reed" electromagnetic sensors or other electromagnetic detection devices, all connected to a control unit located at the operator's station, which control unit has the function of intergrating the electric impulses received from these devices. The front and rear axle of the vehicle are equipped with permanent magnets or devices with similar magnetic effect, that are aligned in the longitudinal plane with the above-mentioned electromagnetic sensors. At passage of the first magnet over a specific magnetic switch said switch closes instantly sending an electric impulse to the central unit that will signal vehicle position. Time elapsed between passage of first and second magnets is computed by the central unit to provide vehicle speed at the moment of its passage over that sensor.
In a conventional application the airflow generator unit for pneumatic propulsion of the vehicle consists in a stationary centrifugal air blower driven by an electric motor. In the present invention a simple method is described to provide a two-speed drive for this blower. It consists in coupling together the propulsion shafts of two electric motors having different rotations, for instance four- and six-pole motors, the two motors becoming linked in series. The assembly is coupled to the air blower. Thus, by energizing one or the other of the electric motors different rotations are selected for operation of the air blower. Since the performance curves of the blower are a function of the rotation, it is possible by this way to select the pressure/flow curve that is more adequate for a specific vehicle performance. For instance, applying higher rotation in the acceleration phase a greater pressure differential is achieved, providing a larger thrust for acceleration of the vehicle. For the constant speed and deceleration phases, a lower-rotation motor may be applied, as a way of reducing the specific energy consumption of these phases. The described arrangement also holds the advantage of motor redundancy, since, in case of failure of one motor, the other will take over, driving the air blower.
Concerning the vehicle, the present invention presents an important improvement for operational safety which is applicable to any vehicle on elevated trackways. Such vehicles must be protected against derailments, caused, for instance, by operating at excessive speed, by effect of high winds or by debris on the rails. The traditional solution for this problem consists adding weight to the vehicle, at the same time lowering its center of gravity as much as possible. In the present invention, the beam that supports the trackway is hollow and is fitted with a longitudinal slit on its upper plane, thus allowing for the installation of retainer wheels that, travelling close to the inner face of the upper beam plane, are connected to the vehicle by a support mast or pylon that passes through the slit. The retainer wheels limit excess vertical movement of the vehicle's wheels to less than wheel retention height on the rail, thus ensuring total safety against derailings. This improvement is applicable to any transportation vehicle on rails, over an elevated trackway, and in the specific case of pneumatically driven vehicles according to the present invention, the mentioned retainer wheels may be associated with the propulsion plate structure. By this way, the assembly propulsion plate-support mast besides performing as the vehicle's traction element also function as the anti-derailing device.
Concerning the vehicle's propulsion plate, this invention presents an improvement of the attachment of the plate to the vehicle, in which the support mast is attached to a main crossbeam of the vehicle's structure by means of a pin, torsion being taken up directly by the vehicle structure by means of a traction bar and swivel joint.
The support mast is positioned behind the propulsion plate, to reduce pressure losses and the mechanical loads at passage through the flexible propulsion duct seal.
Another improvement of the propulsion plate that is presented by this invention, consists in the presence of decompression panels in the propulsion plate structure. The panels have adjustable opening pressure and their purpose is to protect the system's structure against differential pressure peaks in the air duct in excess of a safety level. If, for any reason, the pressure differential between the inside of the duct and the atmosphere reaches the limit, either positive or negative, the decompression panels will move, relieving pressure by equalization of pressure on both sides of the plate, thus protecting the structure of the air duct and/or the propulsion plate itself against excessive pressure differentials.
This invention presents an improvement in the design of the vehicle's wheels. The tread of the wheel is a steel rim, adequately profiled to roll on rails. This rim is tied to the wheel hub exclusively by a layer of rubber of high hardness. In this way, rolling vibrations are dampened, avoiding their transmission to the wheel hub and the vehicle's structure, ensuring a silent and vibration-free ride. Another improvement of the vehicle of the pneumatic propulsion system dealt with in this invention consists in dual independent bogeys. Each bogey is composed of two wheels assembled in one longitudinal plane on axles located at the two ends of a beam which at its center connects with a main crossbeam of the vehicle through a thrust bearing. In conjunction with the symmetrical unit on the other rail, it makes up a wheel system characterized by having four free-spinning wheels independent from each other. On the other hand, the vehicle body is supported on the crossbeams by pneumatic cushions, to dampen vibrations.
An important improvement is introduced in the vehicle's brake system by this invention, consisting in a differential pressure sensor that actuates the brakes whenever the air pressure differential acting on the propulsion plate drops to values close to zero. The sensor is made up by a bellows-type chamber divided in two compartments by a diaphragm. Each compartment is connected to a pressure probe on one side of the propulsion plate. The diaphragm displaces itself from its central position under the effect of the pressure differential between the two sides of the propulsion plate and actuates microswitches that close the electric circuits that will release the brakes. In its central position, signifying lack of differential, the open microswitches will actuate the pneumatic brake actuation system. Considering the zero-pressure differential state means that there is no traction generated by the propulsion plate for the vehicle, it becomes apparent that the brakes will be actuated anytime there is energy loss for the system. Alternatively the pneumatic brake actuation system may be activated manually by an electric switch inside the vehicle.
As concerns vehicle doors, the improvements put forward by this invention consist in lateral double doors that slide along the vehicle's external surface, both sides of each door being actuated by a pneumatic cylinder lodged under the vehicle's floor and interconnected by flex cables on pulleys, to syncronize their movement. Air pressure for the pneumatic cylinders is obtained from a dual electro pneumatic air system fed by on-board batteries.
The system's electro pneumatic valves are controlled by the door control electronic module which adjusts opening time, provides audio warning of door closure and closes the doors, also having door system interlocks, and other functions. On the other hand, frontal windows at both ends of the vehicle allow full opening to provide emergency exit to passengers.
Concerning the vehicle's electric system, the invention presents a method to furnish electrical power to the vehicle from a stationary power supply by rail electrification in with low-tension, alternating current, around 50 volts. Rails are laid on non-conducting mats and can, therefore, be used for this purpose.
A graphite collector brush system on the vehicle's wheel assemblies collects and transmits electrical current into the vehicle, where a transformer-rectifier system conserts to continuous current compatible with the on-board batteries. All electrical demands of the vehicle, such as lighting, sound, energy for the control circuits, and air compressors are met by the batteries, which, in turn, are charged by the supply system above described. For added safety, all described systems are duplicated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a transverse cross-section through a trackway supporting and air channeling beam of a transportation system constructed in accordance with teachings of the instant invention.
FIG. 1A is a lateral side elevation for the trackway of the transportation system.
FIG. 2 is an enlarged fragmentary portion of FIG. 1 in the region of the pneumatic slit.
FIG. 3 is a side elevation of the elements that generate and control pneumatic propulsion in the transportation system.
FIG. 3A is a table showing the combination of control valve positions for various operating modes.
FIG. 4 is a schematic of the control system for pneumatic propulsion.
FIG. 5 is a fragmentary longitudinal cross-section illustrating an air duct shut down valve mounted to a beam of the transportation system.
FIG. 6 is a front elevation of the elements illustrated in FIG. 5.
FIGS. 7 and 8 are front and plan views, respectively, of the suspension for a vehicle of the transportation system.
FIG. 9 is a side elevation of the system that provides air for pneumatic propulsion in the transportation system.
FIGS. 10 and 11 are front and side elevations, respectively, of the vehicle undercarriage and trackway.
FIG. 12 is a front elevation of the elements that protect the transportation system against excessive surges of differential pressure.
FIG. 13 is a side elevation of a decompression channel illustrated in FIG. 12.
FIG. 14 is a cross-section of a wheel taken through a diameter thereof.
FIGS. 15, 16 and 17 are end, plan and side views, respectively, of the independent dual-wheel system for a vehicle of the transportation system.
FIG. 18 is a schematic of the hydraulic brake system for a vehicle of the transportation system.
FIG. 19 is a side elevation of a vehicle for the transportation system.
FIG. 20 is a block diagram of the electrical supply system for a vehicle of the transportation system.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference is made to the enclosed Drawings, that are a part of this descriptive report. FIG. 1 shows a cross-section of a beam having the dual function of providing support for the transportation system trackway and channeling air for pneumatic propulsion of the vehicles. Modules (1) and (2) are precast concrete or steel elements which, when symmetrically laid on pillar (3) together with bottom module (4), also precast in concrete or pre-fabricated in steel make up the mentioned beam. As an assembly, modules (1) (2) and (4) provide the function of a structural beam for support of the transportation system trackway, while its inner volume functions as an air duct for pneumatic propulsion of vehicles. For this purpose the interior of the beam has a constant cross section and is wholly sealed off except on the top surface where a longitudinal slit (6) provides passage to the structural member that connects the propulsion plate that travels inside the beam with the vehicle that travels on rails assembled to the upper surface of the beam.
Modules (1) (2) and (4) may be pre-cast or fabricated in one piece if convenient. In either case, the structure of the lateral modules (1) and (2) is designed to withstand the stresses acting on the assembly, allowing openings to be made in the bottom module (4) for installation of valves or secondary air ducts. The importance of hoops (5) lies in maintaining the rigidity of the top horizontal member (8) of modules (1) and (2) when the assembly is subjected to differential air pressures, avoiding dimensional changes in the width of longitudinal slit (6) which provides passage to the support mast of the vehicle's propulsion plate. Pillar (3) also is a pre-cast or fabricated element that is set on foundation block (7).
The figure shown characterizes a beam that is assembled from modular elements (1) (2) and (4) and is supported on pillars (3) that are erected on foundation blocks (7). The beam has provisions for openings in bottom module (4) for installation of valves or secondary ducts, a longitudinal slit (6) that provides passage to the support mast of the propulsion plate, and reinforcing hoops (5) at both ends. The assembly provides the function of a structural beam for support of the vehicle trackway together with the function of air duct for pneumatic propulsion of vehicles.
In FIG. 1A there is represented a lateral view of a typical stretch (EF) of the trackway of the pneumatic propulsion system object of this invention, having two terminals (E) and (F) for access of passengers and/or freight that are linked by a succession of beams (G) similar to those described in FIG. 1, supported on pillars (3) disposed at regular intervals, it being apparent that a single pillar may support the adjacent ends of two beams (G) and that the beam ends are sealed one against the other by elastic sealants (H).
In FIG. 2 a detail of the beam in FIG. 1 is shown in cross-section, this being the central portion of the upper member (8) of modules (1) and (2), in order to show clearly the seal assembly of the longitudinal slit (6). On this Figure we have two flaps made of flexible material (9) and (10) that are assembled symmetrically to the edges of top member (8) of beam modules (1) and (2). Flaps (9) and (10) are superimposed and, when an air pressure differential, either positive or negative, exists between the interior of the beam and the atmosphere the two flaps will press together providing efficient sealing for the air duct made up by the interior of the beam. On the other hand, the propulsion plate support mast will slide between flaps (9) and (10) pushing them aside momentarily on its passage.
So, FIG. 2 characterizes a sealing system for slit (6) constituted by the flaps of flexible material (9) and (10) mounted symmetrically on the edges of top member (8) of beam modules (1) and (2) in a way that, whenever a pressure differential either positive or negative is established between the interior of the propulsion air duct and the atmosphere, said flaps will press together providing efficient sealing to the propulsion air duct while at the same time giving free passage to the propulsion plate support mast.
FIG. 3 shows the configuration of the equipments for generation and control of pneumatic propulsion, showing the beam whose hollow inner volume functions as the propulsion air duct, a stationary centrifugal air blower (11) or any other airflow generator providing air to the system, connection ducts (12) and a set of four butterfly airflow control valves (13). Said control valves have moving plates that can assume "all open" or "all shut" positions plus several intermediate positions. Specific combinations of these positions allow the airflow from the air generator unit to be channelled to the propulsion air duct in operating modes of "pressure" or suction (overpressure in duct with relation to the atmosphere in duct). The Table of FIG. 3A establishes what combination of positions A, B, C and D of control valves (13) is required in order to obtain operation in "Suction" or "Pressure" modes. For the "Open" position each control valve allows several angular positions of its throttle plate, which may be selected by the system operator providing for modulation of vehicle propulsion in both modes within the performance limits of the airflow generator unit (11). Attention is called to the redundancy present in the two-by-two control valve combination, which ensures total operational safety of this system. In this case of jamming of one valve's throttle plate in an "open" position, its partner provides shutdown of the air circuit, so that in any situation control over propulsion is maintained through the valve in the more closed position. So, this figure characterizes pneumatic propulsion generation and control equipment comprising an air-flow generator unit (11) connected to the main air duct by connection ducts (12) and outfitted with a set of four butterfly control valves (13) whose control from positions "open" to "closed" is effected by a control system in the way described.
In FIG. 4 we have a detail view of the control system for the airflow control valves (13), showing a pneumatic cylinder (14) linked to the command lever (15) that rotates the valve's throttle plate (16). Air pressure for cylinder (14) is supplied by an air compressor (17) and controlled by an electropneumatic valve (18). An electronic miodule of logic circuits (20) selects the proper position of each of the four control valves in accordance with the desred operating mode. The operator has control of the system through lever (19). He may select "pressure" or "suction" modes to establish direction of vehicle motion. At the same time he may graduate the amount of propulsive traction that is applied.
In case of automatic operation of the system, the logic circuits (19) will be controlled by the output module (21) of a control microprocessor. So, this figure shown characterizes the control system of the airflow control valves (13) comprising a pneumatic cylinder (14) linked to a lever (15) that moves the valve's throttle plate (16) this cylinder being controlled by an electropneumatic valve (18) tied to an air compressor (17) said valve being actuated by an electric selector switch (20) in conjunction with an electronic module of logic circuits (19) which, in case of automatic operation of the system is controlled by the output module (21) of a control microprocessor. Refering to the logic circuit electronic module (19) it is pointed out that it sets valves (13) in positions two-by-two to establish the desired airflow and pressure, providing operation of the transportation system in the full range of speeds and vehicle accelerations in both directions of motion through one single control lever (20), the layout of the control valves being such that in case of failure of any one valve, another will ensure control over the propulsion airflow, guaranteeing total operating safety.
In FIG. 5 we have shown the installation of an air duct shutdown valve, showing the beam described in FIG. 1 in longitudinal section.
In FIG. 6 we have a frontal view of FIG. 5, showing the same elements. We see an opening (22) on the bottom of the beam which purpose it is to receive air connecting ducts (12) or the body (23) of the shutdown valve, which comprises a throttle plate (24) actuated by a pneumatic cylinder (25), said plate taking up a fully closed or a fully open position with respect to the air duct. By its design, this valve has minimum actuation efforts, since it is balanced with relation to the air pressure acting on it. So, the two last Figures characterize a shutoff valve that is installed in openings (22) of bottom module (4) having a throttle plate (24) that rotates in body (23) by action of cylinder (25) to block or leave open the air duct, said throttle plate being pressure-balanced.
In FIGS. 7 and 8 we have a frontal and plan view of the structure and wheels of the vehicle, to illustrate how position and speed of the vehicle are determined as it travels along the trackway, providing the operator and/or a control mircroprocessor with continuous information on these parameters. Thus, permanent magnets (26) are attached to the vehicle at two points aligned in the longitudinal direction, while "reed" type magnetic sensors (27) or other electromagnetic detection devices are spaced regularly along the trackway in the same plane as devices (26) on vehicle. Passage of the first device (26) over sensor (27) will trigger an electric pulse that is interpreted by a centrally located electronic unit (28) in terms of vehicle position. Time between passage of the first and second magnet (26) is used by unit (28) to compute speed of vehicle at passage over sensor (27). From this information, other parameters of performance may be computed.
FIG. 9 depicts an air blower with its motor, that provides air for pneumatic propulsion of the transportation system of this invention. A centrifugal blower (29) or any other airflow generator unit is moved by an electric motor (31) through shaft (32) and coupling (30). A second motor (34) is connected to the electric motor (31) through coupling (33), the airflow generator (29) may be actuated by either motor. When motor (34) is actuated, motor (31) will be de-energized behaving like a passive transmission element. In the opposite case, motor (34) will be passively dragged. This arrangement provides operation of the air blower at two speeds, and further provides redundancy, since in case of failure of one motor the other may take over.
FIGS. 10 and 11 depict the undercarriage of the vehicle on the trackway, showing the safety device against derailment adopted by this transportation system. In detail we see the vehicle's base structure (35) and the cross beams (36) on which it is supported. The propulsion plate (37) is connected to the cross beam (36) by the support mast (38) and directly to the vehicle structure by a traction arm (39) and swivel joint (40). It is pointed out that the propulsion plate (37) is located behind the mast (38). Consequently the mast (38) goes through the sealing flaps (9) and (10) in the depressurized area of the propulsion duct, where these seals are no longer subject to differential pressure. Therefore the passage of mast (38) requires less parting effort of the flaps and loss of pressure is minimized. A pair of retainer wheels (41) checks vertical movements of the vehicle, bearing against the top inner surface (8) of the beam thus avoiding loss of contact between wheels and rails. This safety service is applicable to any vehicle travelling on rails over an elevated trackway, as shown in these Figures, where a set of wheels not outfitted with a propulsion plate is shows having a mast (42) on which retainer wheels (41) are mounted connecting to the vehicle crossbeam (36), the assembly having the safety function against derailment described above.
FIGS. 12 and 13 depict the decompression panels (43) installed on the propulsion plate (37) to protect the system against differential pressure surges that might exceed a safety thereshold. Panels (43) are tightly shut by adjustable springs (44). When the differential pressure acting on the propulsion plate (37) exceeds a present value, the resultant thrust overcomes springs (44) pushing panels (43) open permitting air to flow through the openings in the plate, thus equalizing the air pressure differential on same. The air duct structure and the propulsion plate itself are effectively protected against the effect of overpressures.
FIG. 14 depicts a cross section of a vehicle wheel. Structure of wheel (45) has a configuration similar to that of road vehicles, having holes (46) for assembly to a wheel hub, an external flange (47) and retainer ring (48). An outer rim (49) cast in steel, has a profile compatible with the rolling on rails, said rim (49) being embedded in a layer of rubber (50) or other high-hardness elastomer that connects with the external flange (47) and retainer ring (48). In the manufacturing process, wheel structure (45) is assembled from structures elements (45) (47) and (48) and, with outer rim (49) positioned in a mold, the elastomer layer (50) is cast between these elements, said layer being cured in the mold, thus establishing a high-strength elastic connection that ensures good properties of vibration and noise absorption from the wheel/rail contact.
FIGS. 15, 16 and 17 depict the independent dual-wheel system fitted to the vehicle. Air bags (51) are assembled to the crossbeams (36) to support the vehicle's main structure, isolating it from shocks and vibrations coming from wheels (45). Crossbeam (36) also contains the structure (52) of attachment of the support mast (38). Longitudinal beams (53) are swivelled at their center through thrust bearings (56), having at both ends axles (54) onto which wheel assemblies (45) are mounted. A tie bar (55) may be used to adjust parallelism or convergence angle between beams (53). It may be seen that the wheels that roll on one rail have no connection with the wheels on the symmetrical rail. Also, all wheels spin freely without any constraint from traction drives, a unique feature of this system.
FIG. 18 is a schematic of the brake hydraulic system, consisting basically of a differential pressure sensor that commands the brakes whenever the pressure differential across the propulsion plate (37) drops close to zero. The system comprises brake drums (57) inside which brake pads (58) are hydraulically actuated by cylinders (59). Hydraulic pressure is metered by actuation of a lever system by means of a pneumatic cylinder controlled by an electro-pneumatic valve (62). Said valve is electrically actuated by microswitches (63) that are actuated by the displacement of diaphragm (64) that partitions bellows chambers (65) connected to pressure probes (66) and (67) installed respectively in front of and behind propulsion plate (37).
When a pressure differential is established over propulsion plate (37) a resultant force propels the vehicle. This differential is sensed in bellows (65) producing the displacement of diaphragm (64). By its displacement, the diaphragm actuates one of the microswitches (63) closing the electric circuit of valve (62) thereby actuating pneumatic cylinder (61) to release the brakes (57,58). In the absence of a pressure differential across plate (37) pressure in bellows chambers (65) will equalize, diaphragm (64) will centralize remaining out of contact with microswitches (63), thus closing an electric circuit that will actuate pneumatic cylinder (61) to set the brakes. It may be added that, if it is desired to apply brakes in conjunction with deceleration by air thrust, a sense-of-rotation sensor may deactivate microswitch (63) that in this case will be depressed.
FIG. 19 is a lateral view of the vehicle, showing its doors with the respective actuating mechanism, and the emergency doors. Lateral doors (68) are actuated by means of pneumatic cylinders (69), the two sides of each door being synchronized by a system of cables and pulleys (70). Compressed air for cylinders (69) is furnished by dual electropneumatic compressors (72). Control is effected by electropneumatic valves (73) that receive signals from an electronic door control unit or, alternatively, from a manual door selector switch. Frontal windows (74) and (75) may be manually opened staying in the open position by means of hydraulic cylinders (76) providing access of passengers to the trackway for the case of emergency evacuation.
FIG. 20 shows a block diagram of the electric supply system for the vehicle. Transformer (77) located adjacent to the trackway receives public network electricity which it feeds at 55 V to the rails. The purpose of this very low tension is to render the rails, although electrified, harmless to humans, considering the use of the trackway as an evacuation path of passengers. Block (78) represents the rails, which are useable as electric conductors due to their insulation with respect to the beam. Carbon brushes (79) on the vehicle collect electric power from the wheels feeding the vehicle's transformers (80) and rectifiers (81) that feed the on-board batteries (83) with AC current by way of a charging and regulating module (82). | A pneumatic propulsion system for passenger vehicles is constituted by a structural beam, composed of modular elements end-supported on pillars. The beam supports the trackway and provides an air duct for pneumatic propulsion of vehicles. A longitudinal slit in the top surface of the beam is sealed by flexible flaps and that press against each other to seal off the duct, while allowing for the passage of support mast. Airflow for propulsion of the vehicle is generated by a stationary airflow generator, which feeds the air propulsion duct by way of connecting ducts and which is outfitted with a set of four butterfly control valves that are controlled by a command and control system of flow and pressure condition in the duct which actuates the valves pneumatically, allowing automatic or manual selection of "suction" or "pressure" conditions in the duct. Shutoff valves are fitted to openings in the bottom surface of the beam to allow isolation of segments of the propulsion air duct or, alternatively, its venting to connecting ducts or to the atmosphere, allowing by means of a combination of several valves to delimit a specific propulsion air circuit. Traction of the vehicles results from the difference in pressure that is established on opposite sides of propulsion plate by the effect of the airflow generated by the generator unit. A support mast connects to a propulsion plate jointly with a traction arm which transfers the resultant tractive force to the vehicle. Adjustable decompression panels assembled on the propulsion plate assure that a maximum safe pressure differential limit is not exceeded, said limit being controlled by the action of a set of springs positioned on both sides of the propulsion plate. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of provisional patent application Ser. No. 61/023,396, filed Jan. 24, 2008 by the present inventor.
FEDERALLY SPONSORED RESEARCH
Not Applicable.
SEQUENCE LISTING OR PROGRAM
Not Applicable.
BACKGROUND
1. Field of the Disclosure
The present disclosure is related to protective packaging and methods. In particular, to a suspension packaging system and method that suspends an article within a container.
2. Description of the Related Art
Packaging an enclosed article is an art and a science including various requirements of protection, promotion, law, logistics, manufacturing, and materials handling all combined into one. While the functions of a package are various and may include the ability to contain, carry, dispense, identify, and communicate, very rarely can one packaging structure achieve all functions and therefore a combination of more than one packaging structures are combined into a packaging system in order to meet all requirements of an article. Three broad categories cover the scope of a packaging system, primary, secondary, and tertiary packaging. While a primary or first packaging structure such as a formed rigid or semi-rigid retail package such as a blister, skin, or clamshell can decorate and promote or encourage purchase of an enclosed article, a secondary or second packaging structure may be required such as wraps, inserts, liners, foam, pads, or other materials to limit movement within an outer container for transportation and warehousing. To further protect an article from the environment of shock, vibration, and compression, a tertiary or third packaging structure such as an outside container crate, or bulk pack may be required. A packaging system therefore, can quickly become bulky and costly, and forbid one or more desired functions in exchange for the necessary function or primary purpose of a package, to protect an article, especially where an article is fragile and can be best protected when suspended within a container.
There are several suspension packages such as Suspension Packaging U.S. Pat. Nos. 5,388,701 and 5,894,932 and 5,975,307 that suspend articles inside a container, however, they are limited in materials such as they use corrugated which is a material widely used for containment and not as a protective cushioning. A frame is used to sandwich the article between flexible films and suspend the articles in a container. This hammock like configuration leaves the articles susceptible to vibration and the potential to reach resonance, causing damage.
This limits the protection of the article from sinusoidal and random vibration in transportation, where the article bounces up and down with the elasticity of the film hammock configuration while in the container. Even though the suspension feature places the article within the container to protect it from impacts to the outside walls of the container, the article and/or components of an article will still receive g forces and may reach resonance while in transportation and become damaged. Therefore, where articles such as a wine glass would be protected in one of these suspension packages, an electronics article may not. In addition, these suspension packages are hard to assemble if received flat, and bulky if received already assembled causing a high price in warehousing, transportation, and assembly.
Although the need for some structural support has been recognized as found in Retention Packaging such as U.S. Pat. Nos. 5,678,695 and 7,150,356, there is now the limitation of protection from too much packaging contact with the article. In attempting to satisfy the need for structural support the opposite occurs from that of the suspension package that allows space between an impact and the article. If too much packaging material is in contact with an article, shock and vibration travel to the product through the package because there is no space between the impact and the article, and again, while certain articles may do well with a Retention Packaging System, many won't, limiting the number of articles the Retention Packaging can protect.
The present disclosure resolves these issues by suspending an article within a container, keeping it from receiving forces applied to the outside walls of the container, providing structural support by using an arch structure to minimize the contact area, securing it from movement within the packaging system, and providing enough spring in the packaging system to provide cushioning during an impact, drop, and vibration in transportation.
In addition to those primary functions of a packaging system, the present disclosure has unlimited benefits of ease of assembly and dispensing due to the generally planar materials used to form an arch for suspending an article. The planar materials offer low cost in shipping, warehousing, and handling. Thus, constructing a packaging system from planar material that can be left in a flat, compact configuration until it is needed, results in much more efficient storage space.
In addition to those functions of a packaging system, the present disclosure has the benefits of protecting articles from dust, dirt, and moisture.
In addition to those functions of a packaging system, the present disclosure has the benefits of unlimited decoration and communication for retail and gifting. This feature is simply not present in current Suspension and Retention Packaging Systems that focus on the primary functions of protecting the articles they contain.
In addition to those functions of a packaging system, the present disclosure has the benefits of unlimited materials. Several materials and combinations of materials can be used to achieve functions and features that any article would require. Thus, increasing the amount, kinds, and types of articles that can utilize the present disclosure. Because articles are different from another amount, kind, or type of article, so are the characteristics and fragileness, requiring different functions and properties from a packaging system. The present disclosure will be able to satisfy many more requirements than the current Suspension and Retention Packaging Systems as well as be able to receive new materials such as biodegradable materials as they are developed, thus providing a plurality of materials to properly protect and provide unlimited decoration for articles requiring advertising, marketing, and gifting, while being lower in overall costs at the same time.
SUMMARY OF THE DISCLOSURE
The scope of the present disclosure is defined by the appended claims, and nothing in this summary is intended limit those claims.
One aspect of at least one of the illustrative embodiments disclosed herein includes the realization that arch structure of material can be configured to provide positioning, cushioning, and a suspending function within the container. This particular aspect provides several advantages over the available art to provide the following objects:
To provide a package which suspends an article within a container.
To provide a package which protects an article from dust and dirt.
To provide a package which protects an article from shock and vibration.
To provide a package which comprises a plurality of materials.
To provide a package which comprises a plurality of decoration.
To provide a package which provides low cost of warehousing, transportation, and assembly.
To provide a package which displays and communicates well for retail and gifting.
To provide a package that provides a plurality of functions such as to protect, contain, carry, dispense, identify, and communicate an article.
Other objects, advantages, and features will become more readily apparent to those skilled in the art and upon consideration of the following detailed description of the illustrative embodiments and drawings, the disclosure not being limited to any particular preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the disclosure will become apparent from a consideration of the subsequent detailed description presented in connection with the accompanying drawings in which:
FIG. 1 is a perspective view of an illustrative embodiment of a package assembly;
FIG. 2 a is a perspective view of a packaging assembly in accordance with the present disclosure;
FIG. 2 b is a perspective view of a packaging assembly in accordance with the present disclosure;
FIG. 2 c is a perspective view of a packaging assembly in accordance with the present disclosure;
FIG. 3 is an embodiment illustrating a method for assembling a package assembly in accordance with the present Disclosure;
FIG. 4 is a perspective view of a primary packaging assembly in accordance with the present Disclosure;
FIG. 5 is perspective view of a secondary packaging assembly in accordance with the present Disclosure;
FIG. 6 is perspective view of a primary and tertiary package assembly in accordance with the present Disclosure;
FIG. 7 is a perspective view of a secondary and tertiary package assembly in accordance with the present Disclosure;
FIG. 8 is a perspective view of a primary and tertiary gift package assembly in accordance with the present Disclosure;
FIG. 9 is perspective view of a secondary and tertiary package assembly in accordance with the present Disclosure;
FIG. 10 is a perspective view of a display package assembly in accordance with the present Disclosure;
FIG. 11 is a cross-sectional view a packaging assembly in accordance with the present Disclosure;
FIG. 12 is a cross-sectional view a packaging assembly with an additional absorption member in accordance with the present Disclosure;
FIG. 13 a is a cross-sectional view a packaging assembly inverted with an additional absorption member in accordance with the present Disclosure;
FIG. 13 b is a cross-sectional view a packaging assembly inverted in accordance with the present Disclosure;
FIG. 14 is cutaway perspective view of a package assembly in accordance with the present Disclosure;
FIG. 15 is a cross-sectional view of a package assembly in accordance with the present Disclosure;
FIG. 16 is perspective view of a package assembly particularly adapted for large and/or heavy articles in accordance with the present Disclosure;
FIG. 17 is cross-sectional view of a package assembly particularly adapted for large and/or heavy articles in accordance with the present Disclosure;
FIG. 18 is a perspective view of a packaging assembly in accordance with the present Disclosure;
FIG. 19 is a perspective view of a packaging assembly having cutouts in accordance with the present Disclosure;
FIG. 20 is a perspective view of a packaging assembly having cutouts in accordance with the present Disclosure;
FIG. 21 is a perspective view of an alternative exemplary embodiment of a packaging assembly having adhesive features in accordance with the present Disclosure;
FIG. 22 is a perspective view of an alternative exemplary embodiment of a packaging assembly having locking features in accordance with the present Disclosure;
FIG. 23 is a perspective view of an alternative exemplary embodiment of a packaging assembly with extended portions in accordance with the present Disclosure;
FIG. 24 is a perspective view of an alternative exemplary embodiment of a packaging assembly having storage for hardware and accessories in accordance with the present Disclosure;
FIG. 25 is a perspective view of an alternative exemplary embodiment of a packaging assembly having angled portions in accordance with the present Disclosure;
FIG. 26 is a perspective view of an alternative exemplary embodiment of a packaging assembly having structural features in accordance with the present Disclosure;
FIG. 27 a is a top view of a packaging assembly showing assembly members side by side in accordance with the present Disclosure;
FIG. 27 b is a top view of a packaging assembly showing assembly members side by side having decorative features in accordance with the present Disclosure;
FIG. 27 c is a top view of a packaging assembly showing assembly members side by side having decorative features, decorative, structural, cushioning, and cutouts properties in accordance with the present Disclosure;
FIG. 28 a is a perspective view of a packaging assembly in accordance with the present Disclosure;
FIG. 28 b is a perspective view of a packaging assembly and container in accordance with the present Disclosure;
FIG. 28 c is perspective view of a packaging assembly which is positioned inside a container in accordance with the present Disclosure;
FIG. 29 is a perspective view of a variety of exemplary embodiments of single and bulk package assemblies with a single packaging assembly and a plurality of packaging assemblies respectively in accordance with the present Disclosure;
FIG. 30 a is a perspective view of a package assembly with an inverted packaging assembly and container in accordance with the present Disclosure;
FIG. 30 b is a perspective view of a package assembly with an inverted packaging assembly which is positioned inside a container in accordance with the present Disclosure; and
FIG. 31 is a perspective view of a variety of exemplary embodiments of a package assembly with an inverted packaging assembly in accordance with the present Disclosure.
DETAILED DESCRIPTION
For the purposes of promoting an understanding of the principles in accordance with the disclosure, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Any alterations and further modifications of the inventive features illustrated herein, and any additional applications of the principles of the disclosure as illustrated herein, which would normally occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the disclosure claimed.
It must be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise. In describing and claiming the present disclosure, the following terminology will be used in accordance with the definitions set out below. As used herein, the terms “comprising,” “including,” “containing,” “characterized by,” and grammatical equivalents thereof are inclusive or open-ended terms that do not exclude additional, unrecited elements or method processes.
Referring now to FIG. 1 , there is shown an illustrative embodiment of a package assembly 10 in accordance with the principles of this disclosure. The package assembly 10 may provide a container 12 and a packaging assembly 14 with at least one arched member 15 with an arched contour that is anomalous to the contour of article 16 , for suspending and positioning an article 16 within container 12 . The arched member 15 may comprise vertical portions 17 a and 17 b disposed on opposing ends of the arched member 15 . The arched member 15 also may suspend the article 16 away from the inside surfaces of the container 12 .
The packaging assembly 14 in the illustrated embodiment may be held in an arched state by the corresponding sides of the container 12 . Alternatively, the arched member 15 may be formed so as to remain in an arched form without external force. Alternatively, the packaging assembly 14 may be formed so as to remain in an arched form without external force [See, e.g. FIG. 2 c ]. Desirably, the arched member 15 may be resilient for optimally suspending an article 16 in a predetermined manner to respond to anticipated loading. Alternatively, the packaging assembly 14 may be resilient for optimally suspending an article 16 in a predetermined manner to respond to anticipate loading [See, e.g. FIG. 2 a ]. The vertical portions 17 a & 17 b may be sized to correspond to the corresponding dimension (e.g., vertical height) of container 12 . The vertical portions 17 a & 17 b may also be fixedly attached to container 12 , as can be determined by those skilled in the art, as well as the vertical portions 17 a & 17 b can be removably attached to container 12 .
Referring now to FIG. 2 a , there is shown a perspective view of an exemplary embodiment of an unassembled packaging assembly 20 . The packaging assembly 20 may comprise a resilient member 22 , a retention member 26 and a framing member 28 . The article 24 to be packaged is shown in the relative relationship it may typically be placed, such that as the assembly 20 is assembled by bringing resilient member 22 into contact with framing member 28 , article 24 forces retention member 26 to conform to its shape to the shape of the article 24 through opening 29 a of the framing member 28 . It will be appreciated that the resulting structure, as will be fully understood shortly, provides both a very secure packaging system as well as a very aesthetically pleasing presentation of the article to the person receiving the article.
Still referring to FIG. 2 a , the resilient member 22 may comprise fold lines 23 to direct folding along said line during assembly. The resilient member may be made from any suitable material or combination of materials. For example, the following materials may be selected by those skilled in the art in accordance with the present disclosure: paper, pulp, mesh, weave, metal, polymer, copolymer, laminate, composite or fiber (including materials not already available which, when not already rigid are flexible and/or semi-rigid will bend and which, when are rigid or formed to bend) as well as any polymer, copolymer, laminate, mesh or flexible film, including materials not already available with tear resistance, resilience, memory. The recited examples of materials are not intended to be limiting but rather exemplary of the myriad of possibilities. Very heavy articles to be contained may require a resilient member to be made of suitable materials such as a metal (e.g., structural steel) or a synthetic material (e.g., carbon fiber composite) to provide proper strength, and which may be formed to bend at fold lines 23 .
Still referring to FIG. 2 a , it should also be noted that the resilient member 22 may be made of several layers and/or a plurality of resilient members 22 in order to fine tune its functional properties. For example, the present disclosure makes clear that effective suspension and dampening may be achieved using several layers of varying materials to adjust and tune the characteristics of the resilient member 22 to an optimum value in accordance with the application to which the structure is to be placed.
Continuing to refer to FIG. 2 a , resilient member 22 may also comprise one or more opening 29 c therein. The opening 29 c may be sized such that it corresponds to portions of the article 24 . The opening 29 c may include complex shapes corresponding to the complex shapes any article to be contained. Desirably, the resilient member 22 may have decorative elements provided thereon for improving further the aesthetic impression made during presentation of the article 24 to an recipient of the article. The resilient member 22 may have instructions or article information printed thereon or decorative indicia placed thereon.
Still referring to FIG. 2 a , the retention member 26 may comprise fold lines 23 to direct folding along said line during assembly. The retention member 26 may be made from any suitable material or combination of materials. For example, the following materials may be selected by those skilled in the art in accordance with the present disclosure: paper, pulp, mesh, weave, metal, polymer, copolymer, laminate, composite or fiber (including materials not already available which, when not already rigid are flexible and/or semi-rigid will bend and which, when are rigid or formed to bend) as well as any polymer, copolymer, laminate, mesh or flexible film, including materials not already available with tear resistance, resilience, memory. The recited examples of materials are not intended to be limiting but rather exemplary of the myriad of possibilities. Very heavy articles to be contained may require a retention member to be made of suitable materials such as a thermoformed polymer to provide proper strength, and which may be formed to bend or scored to fold at fold lines 23 .
Still referring to FIG. 2 a , it should also be noted that the retention member 26 may be made of several layers and/or a plurality of retention members 26 in order to fine tune its functional properties. For example, the present disclosure makes clear that effective tear resistance, elasticity, and/or tensile strength may be achieved using several layers of varying materials to adjust and tune the characteristics of the retention member 26 to an optimum value in accordance with the application to which the structure is to be placed.
Continuing to refer to FIG. 2 a , retention member 26 may also comprise one or more opening 29 b therein. The opening 29 b may be sized such that it corresponds to portions of the article 24 . The opening 29 b may include complex shapes corresponding to the complex shapes any article to be contained. Desirably, the retention member 26 may have decorative elements provided thereon for improving further the aesthetic impression made during presentation of the article 24 to an recipient of the article. The retention member 26 may have instructions or article information printed thereon or decorative indicia placed thereon.
Still referring to FIG. 2 a , the framing member 28 may comprise fold lines 23 to direct folding along said line during assembly. The framing member 28 may also be made from any suitable material or combination of materials. For example the following materials may be selected by those skilled in the art in accordance with the present disclosure: paper, pulp, metal, polymer, copolymer, laminate, composite or fiber (including materials not already available which, when not already rigid are flexible and/or semi-rigid will bend and which, when are rigid or formed to bend), as well as any polymer, copolymer, laminate, mesh or flexible film (including materials not already available with tear resistance, resilience, memory). The recited examples of materials are not intended to be limiting but rather exemplary of possibilities of materials options.
As indicated above in connection with resilient member 22 and/or retention member 26 , heavy objects may suggest a framing member 28 be made of suitable materials such as a metal (e.g., structural steel) or a synthetic material (e.g., carbon fiber composite) to provide proper strength. It should also be noted that the framing member 28 may be made of several layers and/or a plurality of framing members 28 in order to aid in fine tuning the functional properties. For example, materials can be combined as separate components of the framing member 28 . The present disclosure makes clear that effective printing and advertising may be achieved using several layers of varying materials to adjust and tune the characteristics of the framing members 28 to an optimum value in accordance with the application to which the structure is to be placed.
Continuing to refer to FIG. 2 a , framing member 28 may also comprise one or more opening 29 a therein. The opening 29 a may be sized such that it corresponds to the article 24 . The opening 29 a may include complex shapes corresponding to the complex shapes any article to be contained, such as the article 24 . Desirably, the framing member 28 may have decorative elements provided thereon for improving further the aesthetic impression made during presentation of the article 24 to an recipient of the article. The framing member 28 may have instructions or article information printed thereon or decorative indicia placed thereon.
Referring now to FIG. 2 b , there is shown a perspective view of an exemplary embodiment of an unassembled packaging assembly 21 . As indicated above in connection with FIG. 2 a the packaging assembly 21 may comprise a retention member 21 a . The Retention member may comprise a portion 21 b formed. The retention member 21 may comprise fold lines 21 c to direct folding along said line during assembly.
Referring now to FIG. 2 c , there is shown a perspective view of an exemplary embodiment of an unassembled packaging assembly 25 . As indicated above in connection with FIG. 1 the packaging assembly 25 may comprise a formed arched member 25 a , a formed retention member 25 b , and a formed frame member 25 c.
Referring now to FIG. 3 , there is represented an illustrative method of assembling a package assembly 30 . The process represented by the structures indicated at 31 illustrates the components of a packaging assembly having resilient member 31 a , article 31 b , retention member 31 c and framing member 31 d being readied for use. The process represented at 31 comprises placing an article 31 b onto the resilient member 31 a . Next, the retention member 31 c is laid over the article 31 a and the framing member 31 d is then positioned over the retention member 31 c such that an opening in the framing member 31 d is positioned over the article 31 b.
The process represented by the structures indicated at 32 is illustrative of a process of compressing the components together. The process comprises with the opening in framing member 32 d directly over article 32 b , the framing member 32 d is pressed toward the resilient member 32 a until the members are substantially touching over a substantial part of there opposing faces. By pressing the members together article 32 b protrudes though the opening in framing member 32 d , thereby causing the deformation of the retention member 32 c . The deformation of the retention member 32 c is constrained by both to shape of the article 32 b and the opening in 32 d , thereby creating a pocket around the article 32 b , holding it in place for suspension and display. When the components are pressed in place the result is a packaging assembly 32 n . In the numbering in the figure, “n” is used to represent the combination of “a, b, c, and d.”
In a process for forming the structure illustrated at 33 the packaging assembly 32 n is folded along fold lines 33 e creating vertical portions in the packaging assembly 33 n disposed on either end of the center portion 33 g . The folds may be folded to 90 degrees, and it is also consistent with the disclosure to have angles greater or less than 90 degrees.
In a process for forming the structure illustrated at 34 an arching portion 34 f is formed in packaging assembly 34 n . The arch may be held in a arched state by the corresponding sides of the container. The arch may be formed so as to remain in an arched form without external force. The arch may be pre-tensioned for optimally suspending in a predetermined manner to respond to anticipated loading.
In a process for forming the structure illustrated at 35 the packaging assembly 35 n is placed into a container 35 e forming package assembly 30 . The container 35 e may provide compressive force as an aid in holding the packaging assembly in and arched configuration. Other methods that interchange or slightly modify one or more processes are within the scope of this application.
Referring now to FIG. 4 an illustrative embodiment of a packaging assembly 40 in accordance with the present disclosure is represented. The packaging assembly 40 may provide features to aid in display and presentation of article 44 such as a hang tab 42 for hanging in commonly used display structures. The packaging assembly 40 may desirably be the primary packaging of an article 44 . The primary packaging of an article would be a packaging assembly 40 that holds the article 44 for display absent or naked of any other packaging. For example, the packaging assembly 40 may be fabricated from clear materials such that the article 44 can be readily viewed within the package.
Referring now to FIG. 5 , an illustrative embodiment of a packaging assembly 50 is represented. The packaging assembly 50 may provide features to aid in display such as a hang tab 52 for hanging in commonly used displays. A packaging assembly 50 may be the secondary packaging of an article 54 . A secondarily packaged article would come in its own proprietary and/or primary packaging and would then be secondarily packaged within a packaging assembly 50 .
Referring now to FIG. 6 , an illustrative embodiment of a package assembly 60 in accordance with the present disclosure is represented. The package assembly 60 may provide features to aid in display and presentation and warehousing and shipping of an article 62 with a primary and secondary packaging assembly 61 within a tertiary container 63 . The package assembly 60 as seen in FIG. 6 would desirably provide a centered and upright article upon opening the package. Aside from aiding in the presentation aspect of the article 62 the package assembly 60 would suspend the article 62 in the container 63 for protection. It will be appreciated that the package assembly 60 can be structured in accordance with those structures represented in FIGS. 1-3 .
Referring now to FIG. 7 , an illustrative embodiment of a package assembly 70 is represented. The package assembly 70 may provide features to aid in display and presentation, warehousing and shipping of an article 72 with a secondary packaging assembly 71 within a tertiary container 73 . A package assembly 70 , as seen in FIG. 7 , would provide a centered and upright primary packaged article upon opening the package assembly 70 . In addition to aiding in the presentation of the article 72 , the package assembly 70 would suspend the article 72 in the container 73 for protection. It will be appreciated that the package assembly 70 can be structured in accordance with those structures represented in FIGS. 1-3 .
Referring now to FIG. 8 , an illustrative embodiment of a package assembly 80 is represented. The package assembly 80 may particularly be used in a gift box arrangement having a lid 82 , container 84 and a packaging assembly 86 . Package assembly 86 may provide features to aid in display and presentation of an article 88 as primary packaging within a gift box. The packaging assembly 86 as seen in FIG. 8 provides a centered and upright article 88 upon opening of the gift box. In addition to aiding in the presentation aspect of the article 88 the packaging assembly would suspend the packaged article within the container 84 for protection. It will be appreciated that the packaging assembly 86 can be structured in accordance with those structures represented in FIGS. 1-3 and that decorative and informative indicia can be added to the structures appropriate to the gift occasion.
Referring now to FIG. 9 , an illustrative embodiment of a package assembly 90 is represented. A package assembly 90 may be used in a gift box arrangement having a lid 92 , container 94 and a packaging assembly 96 . Packaging assembly 96 may provide features to aid in display and presentation of an article 98 as secondary packaging within a gift box. A packaging assembly 96 as seen in FIG. 9 provides a centered and upright packaged article upon opening the gift box. In addition to aiding in the presentation aspect of the article 98 the packaging assembly 96 would suspend the packaged article within the container 94 for protection. It will be appreciated that the packaging assembly 96 can be structured in accordance with those structures represented in FIGS. 1-3 and that decorative and informative indicia can be added to the structures appropriate to the gift occasion.
Referring now to FIG. 10 , an illustrative embodiment of a package assembly 110 in accordance with the present disclosure. The package assembly 110 may be used in a retail or trade show display arrangement having, a lid 118 , container 117 , display 116 , and a plurality of packaging assembly 112 . Packaging assembly 112 may provide feature to aid in display and presentation of article 114 as a primary packaging within a display 116 . In a retail environment, the packaging assembly 112 may be used to attractively display articles 114 . The package assembly 116 may contain structures and features that enable them to be stacked or combined in a way that promotes retail floor display. For example, package assembly 110 may include a feature of having a removable display 116 for displaying the contents thereof, or a removable lid 118 to aid in displaying or in shipping.
Referring now to FIG. 11 , a cross-sectional side view of an illustrative embodiment of a packaging assembly 119 in accordance with the present application is represented. The packaging assembly 119 has an arched member 119 a , which supports the article 118 . Where the arched member 119 a makes contact with the article 118 , there are contact points 118 a , 118 b . The arched member 119 a dampens and absorbs forces over the length of the arch, thereby protecting the article 118 . The retention member 119 b holds the article 118 in place by forming around the article 118 as a result of the arched member 119 a and framing member 119 c coming together.
Referring now to FIG. 12 , a cross-sectional side view of another illustrative embodiment of a packaging assembly 120 in accordance with the present application is represented. The packaging assembly 120 has an arched member 122 a , which supports the article 128 . The arched member 122 a dampens and absorbs forces over the length of the arch, thereby protecting the article 128 . Further dampening and protection may be achieved with the addition of an adsorption member 125 . The absorption member 125 makes contact with the article 128 at the contact points 120 a , 120 b , adding more protection to article 128 in addition to the support and protection provided by arched member 122 a . Those skilled in the art will be able to select a single layer of material, or multiple layers of the same or differing materials, from which to fabricate the absorption member 125 in accordance with the present disclosure. The retention member 122 b holds the article 128 in place by forming around the article 128 as a result of the arched member 122 a and framing member 122 c coming together.
Referring now to FIG. 13 a , a cross-sectional side view of an illustrative embodiment of a packaging assembly 130 in accordance with the present application is represented. The packaging assembly 130 has an arched member 130 a , which supports the article 133 . The arched member 130 a dampens and absorbs forces over the length of the arch, thereby protecting the article 133 . Further dampening of forces may be achieved with the addition of an absorption member 134 . The absorption member 134 makes contact with the article 133 at the contact point 131 , adding more protection to article 133 in addition to the support and protection provided by arched member 130 a . As described above in connection with absorption member 125 , those skilled in the art will be able to select a single layer of material, or multiple layers of the same or differing materials, from which to fabricate the absorption member 134 in accordance with the present disclosure. The retention member 130 b holds the article 133 in place by forming around the article 133 as a result of the arched member 130 a and framing member 130 c coming together.
Referring now to FIG. 13 b , a cross-sectional side view of an illustrative embodiment of a packaging assembly 135 in accordance with the present application is represented. The packaging assembly 135 has an arched member 137 a that is in contact with the article 138 . Where the arched member 137 a makes contact with the article 138 there is a contact point 136 . The arched member 137 a supports the article 138 and dampens and absorbs forces over the length of the arch, thereby protecting the article 138 . The retention member 137 b holds the article 138 in place by forming around the article 138 as a result of the arched member 137 a and framing member 137 c coming together.
Referring now to FIG. 14 , a cutaway view of an illustrative embodiment of a package assembly 140 in accordance with the present disclosure is represented. The package assembly 140 suspends the article 141 in the interior of the container 142 away from the walls of the container 142 which are susceptible to impact.
Referring now to FIG. 15 , a cross-sectional side view of an illustrative embodiment of a package assembly 150 in accordance with the present disclosure is represented. The package assembly 150 may comprise a container 151 having flaps 152 a , 152 b , 152 c , and 152 d , and a packaging assembly 153 disposed within the container 151 . The packaging assembly may contact the container at contact points 155 a , 155 b , 155 c , and 155 d . When it is desirable to reduce the degrees of freedom within any system to make the system more predictable and therefore more effective for a targeted task, container 151 may provide locking and affixing means. Flaps 152 a , 152 b , 152 c , and 152 d provide a locking or affixing means at points 155 a , 155 b , 155 c , and 155 d , by impeding movement of packaging assembly 153 while inside container 151 and thereby providing more effective suspension for article 154 . The packaging assembly may contact the container at contact points 155 a , 155 b , 155 c , and 155 d . By dimensioning the packaging assembly at certain points there is a reduction in the degrees of freedom for all remaining points within the packaging assembly. By reducing the degrees of freedom within any system makes the system more predictable and therefore more effective for a targeted task. Flaps 152 a , 152 b , 152 c , and 152 d provide a locking or affixing means at points 155 a , 155 b , 155 c , and 155 d , by impeding the kinematic path of the points 155 a , 155 b , 155 c , and 155 d and thereby providing more effective suspension for a given article 154 .
Referring now to FIG. 16 , there is shown an illustrative embodiment of a heavy duty package assembly 160 . The perspective view illustrates a structure capable of accepting hardware and mechanical and chemical fastening mechanisms and is particularly adapted for storing and shipping large and/or heavy articles.
Referring now to FIG. 17 , a cross-sectional side view of an illustrative embodiment of a package assembly 170 in accordance with the present disclosure is represented. The package assembly 170 may comprise a container 171 having a packaging assembly 173 disposed within the container 171 . By affixing the packaging assembly 173 to the container 171 there is a reduction in the degrees of freedom within the packaging assembly. Mechanical fixtures 174 and fasteners 175 may provide a locking or an affixing means of reduction in the degrees of freedom and thereby providing more effective suspension in a targeted application. By reducing the degrees of freedom within any system makes the system more predictable and therefore more effective for a targeted task. The container 171 can be fabricated from any suitable material with sturdy materials such as metal, wood, plastics and composites being usable.
Referring now to FIG. 18 , there is shown an illustrative embodiment of the separated components of a packaging assembly 180 with adhesives 181 & 182 applied to various surfaces of the members. The adhesives 181 & 182 may provide additional means of fine tuning the suspension of the packaging assembly by locking predetermined members together thereby forcing the members to act together for a composite effect. The adhesives 181 & 182 can be any number of materials having adhesive properties, which can be selected and applied by those skilled in the art using the present disclosure.
Referring now to FIGS. 19 and 20 , there are shown illustrative embodiment of unassembled packaging assemblies 190 and 200 having cutouts 191 , 192 , 201 & 202 . The cutouts 191 , 192 , 201 & 202 may aid in accessing the article, by providing finger holds by which to remove the members and thus the article, from a container. Cutouts may also be used to further secure an article in the packaging assembly and may be placed on each or any assembly member where those skilled in the art will be able to determine in accordance with the present disclosure. Additional means of accessing the articles may be tabs or loops provided on the members, and are contemplated within the scope of the present disclosure.
Referring now to FIG. 21 , there is shown an illustrative embodiment of a packaging assembly 210 having extended portions 211 . In the embodiment of FIG. 21 , adhesive 212 may be provided for locking together the extended portions 211 providing desirable packaging properties.
Referring now to FIG. 22 , there is shown an illustrative embodiment of a packaging assembly 220 having extended portions 221 . In the embodiment of FIG. 22 a latch 222 may be provided for locking together the extended portions 221 providing desirable packaging properties.
Referring now to FIG. 23 , there is shown an illustrative embodiment of a packaging assembly 230 having extended portions 231 . In the embodiment of FIG. 23 extended angled portions 232 connect extended portion 231 to a corresponding end of an arched member 233 providing desirable packaging properties.
Referring now to FIG. 24 , there is shown an illustrative embodiment of a packaging assembly 240 having a storage area 241 for accessories or non-suspended articles providing desirable packaging properties.
Referring now to FIG. 25 , there is shown an illustrative embodiment of a packaging assembly 250 having an angled portions 252 with locking tabs 251 thereby providing additional means for determining the characteristics of the suspension providing desirable packaging properties.
Referring now to FIG. 26 , there is shown an illustrative embodiment of a packaging assembly 260 having structural beams 262 for providing structural integrity to the container and preventing lateral bending within the packaging assembly 260 and providing desirable packaging properties.
Referring now to FIG. 27 a , there is shown a top view of an illustrative embodiment of a packaging assembly 270 . The top view of the packaging assembly members, 271 a , 271 b , 271 c are laid flat, and article 272 , and arranged side-by-side for allowing comparison between members. The packaging assembly members represented in FIG. 27 a can be readily stored in a flat and stacked relationship allowing for efficient use of the space used to store, assemble, and/or ship the members until they are needed for use, or reuse. As seen in FIG. 27 a , resilient member 271 a may comprise article information or decorative indicia placed thereon. Retention member 271 b and framing member 271 c may comprise clear materials to view the decorative indicia placed on resilient member 271 a.
Referring now to FIG. 27 a , there is shown a top view of an illustrative embodiment of a packaging assembly 270 . The top view of the packaging assembly members, 271 a , 271 b , 271 c are laid flat, and article 272 , and arranged side-by-side for allowing comparison between members. The packaging assembly members represented in FIG. 27 a can be readily stored in a flat and stacked relationship allowing for efficient use of the space used to store, assemble, and/or ship the members until they are needed for use, or reuse. As seen in FIG. 27 a , resilient member 271 a may comprise article information, or decorative indicia placed thereon. Retention member 271 b and framing member 271 c may comprise clear materials or decorative indicia placed on resilient member 271 a.
Referring now to FIG. 27 b , there is shown a top view of an illustrative embodiment of a packaging assembly 273 . The top view of packaging assembly members, 274 a and 274 b , are laid flat, and article 275 , and arranged side-by-side for allowing comparison between members. The packaging assembly members represented in FIG. 27 b can be readily stored in a flat and stacked relationship allowing for efficient use of the space used to store, assemble, and/or ship the members until they are needed for use, or reuse. As seen in FIG. 27 b , framing member 274 c may comprise article information or decorative indicia placed thereon.
Referring now to FIG. 27 c , there is shown a top view of an illustrative embodiment of a packaging assembly 276 . The top view of packaging assembly members, 277 a , 277 b , 277 c , 277 d , 277 e are laid flat, and article 278 , and arranged side-by-side for allowing comparison between members. As seen in FIG. 27 c , the packaging assembly 276 may comprise a printing member 277 d . Those skilled in the art will be able to choose different materials with different properties when desired in accordance with this disclosure. Absorption assembly member 277 b dampens and absorbs forces adding additional protection for fragile articles. Assembly members 277 a and 277 b may comprise cutouts 279 a and 279 b which aid in protecting fragile components of an article in accordance with this disclosure. The packaging assembly members represented in FIG. 27 c can be readily stored in a flat and stacked relationship allowing for efficient use of the space used to store, assemble, and/or ship the members until they are needed for use, or reuse. When not stored flat it will be appreciated that the structures represented in package assembly 276 can be structured in accordance with those structures represented in FIG. 3 .
Referring now to FIG. 27 c , there is shown a top view of an illustrative embodiment of a packaging assembly 276 . The top view of packaging assembly members, 277 a , 277 b , 277 c , 277 d , 277 e are laid flat, and article 278 , and arranged side-by-side for allowing comparison between members. As seen in FIG. 27 c , the packaging assembly 276 may comprise a printing assembly member 277 d . Those skilled in the art will be able to choose different materials with different properties when desired in accordance with this disclosure. Absorption assembly member 277 b dampens and absorbs forces adding additional protection for fragile articles. Assembly members 277 a and 277 b may comprise cutouts 279 a and 279 b which aid in protecting fragile components of an article in accordance with this disclosure. The packaging assembly members represented in FIG. 27 c can be readily stored in a flat and stacked relationship allowing for efficient use of the space used to store, assemble, and/or ship the members until they are needed for use, or reuse.
Referring now to FIG. 28 a , there is shown an illustrative embodiment of a packaging assembly 281 similar to those represented in FIG. 27 a shown arranged ready for receiving an article to be safely stored and/or shipped.
Referring now to FIG. 28 b , there is shown an illustrative embodiment of package assembly 280 with the packaging assembly 281 represented in FIG. 28 a in an exploded view showing a typical fitment of structures inside of a container 282 .
Referring now to FIG. 28 c , there is shown an illustrative embodiment of a package assembly 280 , which is ready to be sealed for storage or shipment, which includes packaging assembly 281 and container 282 structures from FIGS. 28 a - 28 c.
Referring now to FIG. 29 , there are shown illustrative embodiments of package assemblies 280 and 283 in correspondence to the present disclosure are represented. Package assembly 280 representing various decorative aspects of the packaging assembly 281 , and may include a single packaging assembly inside container 282 or as shown in package assembly 283 a plurality of packaging assemblies 281 inside container 284 . Decorative aspects may include color, texture, and prints, or arrangements of a single packaging assembly 281 inside a container 282 , or arranged in bulk inside container 284 , or arranged inside a container for display as indicated above in connection with FIG. 10 .
Referring now to FIG. 30 a , there is shown an illustrative embodiment of package assembly 280 with arched member 281 shown in expanded view ready to be inserted in an arched up configuration into a container 282 .
Referring now to FIG. 30 b , there is shown an illustrative embodiment of a package assembly 280 ready to be closed with the arched member 281 in an arched up configuration similar to the structures of FIG. 30 a inside container 282 .
Referring now to FIG. 31 , there are shown alternative illustrative embodiments of package assemblies 280 similar to the structures of FIGS. 30 a - 30 b in accordance with the present disclosure. Package assemblies 280 , with arched member 281 inverted inside container 282 , and illustrating various potential decorative aspects of the packaging assembly 281 . Decorative aspects of packaging assembly 281 may include color, texture, prints, and a singular arrangement within a container 282 , or a plurality arrangement within a bulk container or display container as indicated above in FIG. 29 and FIG. 10 respectively.
In view of the foregoing, those having ordinary skill in the relevant art will appreciate the advantages provided by the features of the present disclosure. Those advantages comprising; cost savings, economy of storage, and the ability to fine-tune the properties of the packaging.
In the foregoing Detailed Description, various features of the present disclosure are grouped together in single embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed disclosure requires more features than are expressly recited in each claim hereinafter presented. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the following claims are hereby incorporated into this Detailed Description by this reference, with each claim standing on its own as a separate embodiment of the present disclosure.
It is to be understood that the above-described arrangements are only illustrative of the application of the principles of the present disclosure. Numerous modifications and alternative arrangements may be devised by those skilled in the art without departing from the spirit and scope of the present disclosure and the appended claims are intended to cover such modifications and arrangements. Thus, while the present disclosure has been shown in the drawings and described above with particularity and detail, it will be apparent to those of ordinary skill in the art that numerous modifications, including, but not limited to, variations in size, materials, shape, form, function and manner of operation, assembly and use may be made without departing from the principles and concepts set forth herein. | A packaging assembly is disclosed. The packaging assembly is easily assembled and disassembled for convenient use and provides suspension of an enclosed article by way of an arched structure providing protection from impact, shock and vibration. This suspension package and method is called KLOS Pak. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/232,475 filed Sept. 13, 2000.
FIELD OF THE INVENTION
[0002] The present invention relates to a linear optical scanner for use in scanning two dimensional and three dimensional objects, and more particularly to a linear optical scanner having a three-mirror configuration causing the image from a lens to be shifted across a linear array of one-dimensional detectors of a linear array camera.
BACKGROUND OF THE INVENTION
[0003] Prior art methods of scanning two-dimensional scenes with a linear array camera are mostly dependent on either physically moving or translating the object to be scanned, physically moving or translating the entire camera and lens assembly; or optically redirecting the field of view of the camera and lens. by use of a single rotating scanning mirror; or an assembly of multiple mirrors in a rotating or translating configuration.
[0004] In the first two cases, translation of either the object or the camera and lens requires moving relatively large masses over relatively long distances. Mechanical realization of these systems results in expensive and slow mechanisms. For the third case, mirror rotation introduces at least two forms of scan error. One form of scan error is non-linearity due to converting rotational motion into linear motion. The second form of scan error is defocusing due to a change in optical path length either between the object and lens or the lens and the image plane.
[0005] In general, for any prior art scanning mirror or prism system, one of the two scan errors described occurs and must usually be corrected in some manner such as with the use of additional moving correcting mirrors or with limited utility f-theta lenses.
[0006] Several techniques are currently available for optically scanning an object or scene. However, all known methods suffer either from scan errors, or require movement of relatively large masses.
[0007] An object of the present invention is to produce a linear array camera having a linear optical scanning device that allows theoretically perfect linear translation of an image without defocus or other scan errors.
[0008] Another object of the present invention is to produce a linear array camera having a linear optical scanning device that may be constructed having a smaller size than equivalent performance devices of prior art, and allows theoretically perfect linear scanning of a large object field.
[0009] Another object of the present invention is to produce a linear array camera having a linear optical scanning device whereby adaptation for use with a large variety of lens types and focal lengths is simplified.
[0010] Still another object of the present invention is to produce a linear array camera having a linear optical scanning device whereby insertion of the linear optical scanning device into the image space between a lens and a camera or detector, when used with lenses with long back focal lengths, is simplified.
SUMMARY OF THE INVENTION
[0011] The above, as well as other objects of the invention, may be readily achieved by a linear optical scanner comprising: a mirror assembly including a plurality of mirrors, each of the mirrors having a reflective surface; and a drive means operatively connected to the mirror assembly for mechanical translation of the mirror assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The above, as well as other objects, features, and advantages of the present invention will be readily apparent to those skilled in the art from reading the detailed description of the preferred embodiments of the present invention when considered in light of the accompanying drawings, in which:
[0013] [0013]FIG. 1 is a schematic view illustrating a linear array camera requiring object or image motion relative to the linear array photo-detector;
[0014] [0014]FIG. 2 is a schematic view of a linear optical scanner, illustrating two forms of scan error: non-linearity due to converting rotational motion into linear motion, and defocusing due to a change in optical path length between the object and lens or the lens and the image plane;
[0015] [0015]FIG. 3 is a schematic view of a linear optical scanner incorporating the three-mirror configuration of the present invention;
[0016] [0016]FIG. 4 is a schematic view of a linear optical scanner incorporating the features of the present invention whereby the mirror assembly is fixed at a distance dl from the optical axis;
[0017] [0017]FIG. 5 is a schematic view of a linear optical scanner incorporating the features of the present invention whereby the mirror assembly is fixed at a second distance d2 from the optical axis;
[0018] [0018]FIG. 6 is a schematic view of a linear optical scanner incorporating the features of the present invention whereby the mirror assembly is fixed at a third distance d3 from the optical axis; and
[0019] [0019]FIG. 7 is a plan view of a linear array camera incorporating the features of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0020] Referring to the drawings, FIGS. 1 and 2 illustrate the prior art showing the basic concept of requiring object or image motion relative to the linear array photo-detector. There is also disclosed two types of errors, specifically showing the effects with a single scanning mirror rotating about an axis into the plane of the page. The mirror is shown at three equally spaced angular positions with 1 being equal to 2. For each angular position, the point of best focus in object space is shown as p0, p1 and p2. The vertical distances between each of these points are not equal and in general change non-linearly as a function of the mirror angle . Likewise, the horizontal distances df1 and df2 from the object plane are shown to be non-zero, increasing non-linearly as increases.
[0021] The present invention utilizes a simple three-mirror assembly in a configuration sometimes known as an Abbe k-mirror. FIG. 3 discloses such an assembly which is placed between a lens L, and the image plane IP of the lens. The three mirrors are arranged as follows: the reflecting plane of the first mirror M 1 is disposed to make an angle with the optical axis OA of the lens. The reflecting plane of the second mirror M 2 is parallel to the optical axis of the lens, and at a distance s from the upper edge of M 1 , as shown. The reflecting plane of the third mirror M 3 is also disposed to make an angle with the optical axis, wherein the angle is equal in magnitude, but opposite in sign to the angle formed between the mirror M 1 and the optical axis OA. Usually the upper edge of the mirror M 3 is coincident with the upper edge of the mirror M 1 . Such a k-mirror assembly has previously been used to provide a means of rotating images in a manner similar to that of a Dove Prism. This is achieved by rotating the assembly about the optical axis OA. For the present invention, the k-mirror is translated only, and in a direction that is parallel or anti-parallel to the normal N of the single plane mirror M 2 .
[0022] Also shown in FIG. 3 are: object points O 1 , O 2 , and O 3 that lie on the object plane OP; and conjugate image points I 1 , I 2 , and I 3 that lie on the image plane IP as it would exist if the mirror assembly were not in place.
[0023] In general, when such a mirror assembly is placed between a lens and an image plane and translated by a distance d in a direction that is parallel or anti-parallel to N, the image is shifted in the same direction, but by a distance that is exactly equal to twice d. FIGS. 4, 5, and 6 illustrate an example of the case for three different positions of the mirror assembly with the proper reflections from the mirrors being shown.
[0024] [0024]FIG. 4 shows the position of the mirror assembly where the distance in the N-direction from the mirror M 2 to the optical axis OA is dl. In this case, the reflected path of the image space light rays is shown such that I 1 still lies on the optical axis OA, but is translated a distance D from the original image plane IP onto a new image plane IP′. The new position is noted as I 1 ′ and is simply the result of the additional mechanical path length introduced by the k-mirror assembly. The image points I 2 and I 3 are likewise shown to be translated to the new image plane IP′ and have been designated as I 2 ′ and I 3 ′. In addition, the relative positions of all three new image points have been inverted.
[0025] It must be noted that in actual fact for the specific arrangement shown, the light rays contributing to I 3 ′ would not actually converge to the point shown. The I 3 ′ rays reflect from the mirrors M 1 and M 2 , and then strike the mirror M 1 again instead of the mirror M 3 , then the mirror M 2 again, eventually converging to the real image point P 3 ′. This is because the k-mirror assembly as represented is not large enough. The rays I 3 ′ are thus lost to the image plane IP′. Nevertheless, the gray lines are shown where these rays would have converged had they struck the mirror M 3 immediately after being reflected from the mirror M 2 .
[0026] Also shown in FIG. 4 is the location of a possible linear array LA of photodetectors that is chosen to be coincident with I 1 ′. The linear array LA is disposed such that the long axis of such a one-dimensional detector device is shown extending into the page. The type of detector has no receiving elements above or below the optical axis as shown. Thus, the loss of the rays I 3 ′ to the image plane IP′ is irrelevant, as these rays do not contribute to detectable light for the illustrated position of the k-mirror.
[0027] [0027]FIG. 5 shows the mirror assembly having been moved anti-parallel to N so that the mirror M 2 now lies a distance d2 from the optical axis OA. The distance moved, d1-d2, is chosen to be exactly half the distance between I 1 ′ and I 2 ′. The reflected path of the image space light rays now shows that all three image points I 1 ′, I 2 ′, and I 3 ′ have been shifted anti-parallel to N by a distance equal to twice d1-d2, and the image point I 2 ′ is exactly coincident with the linear array LA.
[0028] Finally, FIG. 6 shows the mirror assembly having been moved anti-parallel to N so that the mirror M 2 now lies a distance d3 from the optical axis OA. The distance moved d1-d3 is chosen to be exactly half the distance between the image points IP 1 ′ and IP 3 ′. The reflected path of the image space light rays shows that all three image points have been shifted anti-parallel to N by a distance that is twice d1-d3, and that the image point I 3 ′ is exactly coincident with the linear array LA.
[0029] Again, it must be noted that in actual fact some of the image point light rays are lost to the image plane IP′. As illustrated some of the rays contributing to I 1 ′ do not reach IP′. The gray line shown indicates where one I 1 ′ ray would have converged had it not missed striking M 1 initially instead of converging to point P 1 ′ shown. Again, however, these rays would not contribute to light detection at LA, and so the loss is irrelevant.
[0030] The description and the drawings include light rays tracing from the upper half of a full set of object points, assuming that the optical system is viewing the center of an object. Lack of inclusion of other object points is solely to maintain clarity and comprehensibility of disclosure. It has been found that movement of the k-mirror assembly in a direction parallel to N will result in exactly the same type of image shift in the N-direction.
[0031] The proof of the concept of the present linear optical scanning device may be found by simple geometric ray tracing of light rays reflected from the three mirrors of the k-mirror assembly. Modern computer automated design (CAD) software programs may be used to model the system with almost any degree of accuracy desired. The limitation is only dependent on the inherent accuracy of the software. Such modeling shows that given a perfect lens, perfect construction of the k-mirror, and perfect mechanical translation mechanism, the image shift is always exactly equal to twice the k-mirror shift, and there is no defocus whatsoever at the image plane.
[0032] The present invention obviates the need for correction because the scan errors do not occur. Furthermore, the scanning may be achieved with a relatively small, low mass mechanism. Such a feature provides significant advantage over the previously described method of mechanically translating the object or the camera and lens.
[0033] Furthermore, other prior art devices that produce “flat field” linear scanning require either complex cam and rack mechanisms designed for a specific application, such as, for example, U.S. Pat. No. 5,058,968 to Stark, or are limited to object space telecentric imaging that is not suited for large object scanning, U.S. Pat. No. 4,647,144, to Finkel. Also, in these cases, the corresponding mechanisms are not suited for simple, broad use with a wide variety of lenses.
[0034] In the preferred embodiment of the present invention, a three-mirror k-mirror configuration as has been shown, with the angles between M 1 and the optical axis being 150 degrees, the angle between M 3 and the optical axis being −150 degrees, and the angle between M 2 and the optical axis being zero degrees. Other angles and other configurations are possible, including those with an odd number of mirrors greater than 3. The described simple k-configuration, however, appears to require the least amount of optical path length, thus making it more suited for use with a broader range of lenses.
[0035] Further, the preferred embodiment of the present invention allows for use of the linear optical scanning device with lenses that have relatively long back focal lengths. Because of the optical path length that even simple multi-mirror arrangements require, longer back focal lengths are preferred.
[0036] The preferred embodiment of the present invention also utilizes a lens that provides flat-field imaging and low optical distortion. The linear optical scanning device itself is capable of perfect linear performance with no focus error. Therefore, a lens that does not produce a flat field and low distortion (neon-linear imaging) in the first place defeats some of the purposes of the linear optical scanning device. Two examples of good lenses for use with the linear optical scanning device are high quality photographic objectives, and photographic enlarger lenses.
[0037] Additionally, the preferred embodiment of the present invention utilizes lenses operated at relatively high F-number/small numeric aperture settings. As the working F-number of the lens decreases, the solid angle of cones of light coming from the exit pupil of the lens increases. As this occurs, the scanner mirror assembly must be made larger in order to collect all the useable light and prevent vignetting. Enlarging the scanner mirror assembly will tend to negate the advantage of having a compact linear optical scanning device design. Furthermore, additional mechanical path length is required for larger mirror assemblies.
[0038] The preferred embodiment of the present invention further utilizes a highly linear mechanical motion of the k-mirror assembly. Again, the image motion is exactly twice that of the mechanical motion. Any mechanical errors will be reflected in the image motion, and with twice the magnitude. It is understood, however, that there may be applications in which nonlinear image motion is desired.
[0039] In order to prevent stray or direct light from reaching the image plane, light blocking baffles should be used in conjunction with the k-mirror assembly.
[0040] For broadest utility, the linear optical scanning device should be housed in an enclosure that allows easy use with a variety of lens types and focal lengths, as well as a variety of camera types.
[0041] Referring now to FIG. 7, there is shown generally at 10 a linear array camera illustrating a preferred embodiment of the present invention. The linear array camera 10 includes a linear optical scanner 12 having a first mirror 14 , a second mirror 16 , and a third mirror 18 disposed on a mounting plate 20 . The mounting plate 20 is operatively disposed on a plurality of slide rails 22 . The plurality of slide rails 22 are disposed on a frame 24 and slidingly disposed on the mounting plate 20 . Additionally, a plurality of light baffles 26 are disposed on the mounting plate 20 . A drive screw 28 is centrally disposed in the frame 24 and rotatably connected to the mounting plate 20 . A drive means 30 is disposed on the drive screw 28 . A camera adapter means 32 is disposed adjacent to the frame 24 . A camera lens adapter 34 is disposed adjacent to the frame 24 opposite the camera adapter means 32 . A camera lens 36 is disposed within the camera lens adapter 34 . A linear array of one-dimensional photo-detectors 38 is disposed adjacent to the camera adapter means 32 and opposite the frame 24 . The linear array camera 10 is further disposed within the hollow interior of a housing 40 .
[0042] While specification has been made to a screw drive means, it will be understood that the other drive means may be satisfactorily employed. The drive means may consist of a stepper motor, servomotor or any other rotating motor coupled to a drive screw that moves the mirror assembly. A rotating motor may also drive a rack and pinion arrangement, or a direct contact cam whose shape is designed to convert rotary motion into linear motion. One such possible cam shape is the so-called “Spiral of Archimedes”. Direct linear drives may also be employed. Such drives may include linear motors in which the otherwise conventional stator and rotor are “unwrapped” into straight lines, direct linear piezoelectric actuators, voice coil actuators, or any other type of linear actuator such as solenoids or even pneumatic or hydraulic cylinders.
[0043] From the foregoing description, one ordinarily skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications to the invention to adapt it to various usages and conditions in accordance with the scope of the appended claims. | A linear optical scanner wherein the linear optical scanner is disposed between a lens and the image plane of the lens allowing the image from the lens to be optically shifted along one dimension, and permits the image from the lens to be shifted linearly without scan error. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of provisional application "Facsimile Form Generation," filed Nov. 28, 1995, bearing Ser. No. 60/007,645, the contents of which are relied upon and incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of Invention
The present invention relates to a document preparation and delivery system, and more particularly to a system and method for preparing and sending documents via facsimile to a plurality of customers, each customer document having a plurality of unique data values.
Although applicable for many applications, the present invention is particularly suitable for stock brokerage and security firms and will be described in that connection.
2. Description of the Related Art
Many businesses require sending information to clients on a regular basis and in a very timely manner. For example, in the stock brokerage and securities area, a brokerage firm is required by law to send confirmation of stock trades to their clients in less than one calendar day. Because the cost of overnight mail carriers is prohibitive, other options such as facsimile delivery are used.
However, it is extremely time consuming for a firm to prepare and send via facsimile a large number of documents to a plurality of different telephone numbers. In one system, a facsimile vendor stores a customer form. Then the securities firm sends in data which is typed at distinct locations to fit the form. That is, for example, the name to be placed in the "to" field is positioned on the client's screen in the exact position it will be on the form. If there are a plurality of blank lines then a plurality of blank lines will be sent. This requires a great deal of data to be sent from the client to the fax vendor, who then superimposes the data over the stored form and transmits the facsimile to a plurality of different customer sites. Accordingly, this prior system required that a securities firm send a large amount of data to a fax vendor and spend a great deal of time preparing and formatting the data.
In light of the foregoing, there is a need for a facsimile system where the firm may send a minimal amount of information in a simplified format to a fax vendor, saving both time and money for the securities firm.
SUMMARY OF THE INVENTION
Accordingly, the present invention is directed to a computer readable medium that includes data corresponding to a pre-formatted form having a group of fields arranged at designated locations on the form, and having instructions configured to extract information from received data that includes a key value section and a data section. The key value section defines the order of the field data that will follow in the data section. The fields in a form are populated with the received data in the corresponding fields defined by the key value section. The data section may include data for a plurality of separate forms. Common data information that is to be included in each form may be defined in the key value section and inserted in each form to be transmitted.
In another aspect, a system for facsimile transmission of documents includes a memory for storing a form with a plurality of fields, structure for receiving data identifying a pre-formatted form having fields, data defining a sequence that data will be sent for insertion into fields in the pre-formatted form, structure for populating the fields with received data and then transmitting the generated facsimiles.
In another aspect, a method for preparing documents for facsimile transmission includes the steps of receiving sets of data from an external device that each corresponds to a stored pre-formatted form. The data values in each data set are used to populate a form to generate a completed document. The completed documents are output via facsimile.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated and constitute part of the specification, illustrate a presently and preferred implementation of this invention and, together with the general description given above and the detailed description of the preferred implementation given below, serve to explain the principles of the invention.
In the Drawings:
FIG. 1 is a block diagram of a system for preparing documents for facsimile transmission according to the present invention;
FIG. 2A shows an example of a pre-formatted form that may be used by the system of FIG. 1;
FIG. 2B shows an example of a completed form generated by the system of FIG. 1;
FIG. 3 is a flow chart of the steps required to configure the system for the preparation of facsimile documents for transmission by the system of FIG. 1; and
FIG. 4 is a flow chart of the steps for processing received data to generate documents for facsimile transmission by the system of FIG. 1 configured according to FIG. 3.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to the construction and operation of a preferred implementation of the present invention which is illustrated in the accompanying drawings. The following description of the preferred implementation of the present invention is only exemplary of the invention. The present invention is not limited to this implementation, but may be realized by other implementations.
FIG. 1 illustrates one implementation of the present invention. The data input device 100 inputs data to a computer system 120 that includes processor 130, computer readable medium 140, input data storage 150, initial processing instructions 160, instructions for processing received data strings to generate completed forms 170, and instructions for outputting processed forms 180. The computer system may output information through a facsimile device 190. The computer readable medium may be a computer memory or any other computer readable device.
The input data storage 150 stores data corresponding to a pre-formatted form having a group of fields at designated locations in the pre-formatted form. The example pre-formatted form is shown in FIG. 2 and has a title, F&M Securities, a field 1 for insertion of a name, a field 2 for insertion of account information, a field 3 for insertion of stock information, and a field 4 for insertion of a message. The initial processing instructions 160 include instructions for receiving and storing information about preformatted forms in the input data storage 150.
Initially customer companies such as F&M Securities, supply a business form to the facsimile vendor such as that shown in FIG. 2A, and a sample of how the form should appear after being printed such as that shown in FIG. 2B. FIG. 3 shows the steps for creating the initial forms that are stored in the input data storage 150. The blank titled form is received (step 300), and a sample of the completed form such as that shown in FIG. 2B is received (step 310). A unique field identifier must be provided for each field in the form (step 320). The title of the form, or some other designated identifier is stored as a template identifier (step 330). An image of the form is stored as an overlay (step 340). The image of the form may be generated by drawing the document to scale using page layout software such as FrameMaker made by Adobe running on an operating system such as Solaris made by Sun Microsystems, Inc. The present invention utilizes a script, which is a program that describes how text and graphics are to be combined with one or more overlays to produce a document. The script includes instructions for where to place each field on an overlay and includes formatting information defining how data is to be placed and appear in each field. For example, the script will define the location of the name field on the document page and may describe a location of fields in relation to one another. An overlay is a one page pre-stored raster image used as a background on a fax with form data, and a template is a collection of a script and zero or more overlays.
A script may be created using a basic understanding of programming languages and using any programming language such as Xbase, dBase, Clipper, LISP, BASIC and Microsoft's Visual Basic.
The script is compiled (step 360) and, when the compilation is determined to be successful, the script and overlay are stored together as a template (step 370). Otherwise an error message is output to the user of computer system 210 (step 375). The compiling step is the most time consuming step. Therefore, it is desirable to precompile the script or to place the compiler on another computer system separate from computer system 210.
After templates have been stored in the input data storage 150, a customer may download data to the present invention in a variety of ways using communication programs such as ProComm communications software produced by Quarterdeck Inc. (step 400). The instructions for processing received data strings 170 parse through received data strings from data input device 100, and populate a group of fields in an identified pre-formatted form. The following is an example of a received data string having a keyword value section and a data section:
______________________________________Keyword Value Section______________________________________Template: F&M.sub.-- SecuritiesDDEFINITION: FAX, NAME, ACCT, STOCKCDEFINITION: MESSAGEData SectionThe latest stock trade information. (Common Data)202-123-4567; John Smith, 56789, Cable: $35879; (Data Set 1)202-124-5678; Jennifer Thomas, 54321, (Data Set 2)Enterprise: $40000;______________________________________
Computer system 120 receives the data and processor 130 extracts a keyword value section (step 410). Computer system 120 first determines whether the template identified exists (step 415). If not, an error message is output to the user (step 418). Otherwise, the identified template is retrieved (step 420). The script associated with the identified template is stored in a local work space in the computer system 120 (step 430). Form overlays associated with the identified template is loaded into the local work space of the computer system 120 as they are referenced by the script (step 440).
Data definitions (DDEFINITIONS) and common data definitions (CDEFINITIONS) that are included in the keyword value section are extracted (step 450). The DDEFINITIONS provides a list of comma separated field names that are in the form. In one embodiment, the first few field names in the DDEFINITION are reserved names for information such as a phone number destination for a facsimile. The CDEFINITION lists comma separated field names that will contain common data. For example, if a firm wishes to include the same message of the day in each facsimile, this message of the day will be inserted in the section referred to as common data. The data section includes data pieces separated by commas. Each data piece corresponds to a field on the identified corresponding form. The list of fields in the CDEFINITION and DDEFINITION defines the order of the data in the data section.
In the example above, the CDEFINITION indicates that the message field 4 of each form to be defined in the data section will contain the same message. The data section begins with data for insertion in the common data fields defined in the CDEFINITION. The DDEFINITION shown above indicates that each data set will list a fax number followed by a name for field 1, account number for field 2, and stock information for field 3.
The data section includes two data sets after the defined common data, each set corresponding to a different form. The sets are distinguished by being on different lines or by a character such as ";" or "/." In the example, there are two data sets, one data set corresponding to a form to be sent to John Smith and the other data set corresponding to a form to be sent to Jennifer Thomas. Each set includes a data piece corresponding to each field listed in the DDEFINITION. The data pieces are separated by a character such as a comma, but any predefined character may be used. If the data has an embedded comma, it must be framed with another character such as quote marks, such as "Arlington, Virginia." The DDEFINITION shown above indicates that the data pieces will first list a facsimile number followed by a name field, an account field, and a stock field. If a field is to be left black, then two separators, such as the separator comma shown, will be listed in a row.
Computer system 320 determines whether the number of data values provided in each data set correspond to the number of identifiers provided in the combined CDEFINITION and DDEFINITION areas (step 412). If not, an error message is output to the user (step 418). Otherwise, based on the DDEFINITION, the first data piece from the first line of data of the first set of data is inserted in the associated field of the form (step 460). The computer system 120 determines whether there are additional data pieces in the data set (step 465). If so, the next piece of data, which belongs in the next identified field, will be inserted (step 470). When it is determined that there are no additional data pieces in the data set (step 465), then data provided in the CDEFINITION is inserted in the appropriate field in the form. In the example, the message "The latest stock trade information." is inserted in the message field of every form generated. The completed form that includes all of the data given by the user will be stored as a completed form (step 480).
If it is determined that there is another set of data (step 485), then the first data piece in that set is inserted into an associated field of the next form (step 490), where each set of data corresponds to another distinct form document. When it is determined that there are no additional sets of data to be processed (step 485), then processing is complete and the set of completed documents are sent via facsimile to the facsimile number associated with each (step 495). If a facsimile number is busy or out of paper, the computer system 120 will repeatedly attempt to send the document until a successful connection is achieved.
In one implementation of the present invention, a customer may designate special processing at the time the script is developed in order to provide additional functions. For example, the customer may indicate that certain fields in the form will have a plurality of values. In the example shown in FIG. 2A, the customer may wish to provide a plurality of stock transactions and may wish to have the stock field repeated on the completed form. The script will include instructions for checking for a specific flag or character such as ";" which will be inserted in between values to indicate that each of the values belongs in the same field. If, at the time of initializing a script, a customer knows that a certain data field will have a plurality of data values, the script may be written with instructions to check for the plurality of data values and to either insert the many data values on one page or on additional pages as required.
Another type of special processing is to require that some customers receive a different overlay than others in which case the script will include instructions to check for a specific character that indicates to use an alternate overlay for this form.
A user may request that a certain field have text in bold, in which case the script will look for a character to indicate which fields are to be placed in bold for a specific customer, such as by placing a ";" in between values for the same field.
A user may wish to have a string of data printed on one line on the facsimile document but desire to enter the data on different lines in the data section of the download, in which case a special character may be placed at the end of the line before a return to indicate that the next line of data should continue with the current line of data. These are examples of the many types of special processing a user may desire that can be accomplished by altering the script of the present invention.
In one implementation of the present invention there are many distributed computer sites that include the software on computer system 120. The site closest to the destination of the facsimile should be used to compile the documents in order to save transmission costs.
While there has been illustrated and described what are at present considered to be a preferred embodiment and method of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made, and equivalents may be substituted for elements thereof without departing from the true scope of the invention. Modifications may be made to adapt a particular element, technique, or implementation to the teachings of the present invention without departing from the spirit of the invention. Therefore, it is intended that this invention not be limited to the particular embodiment and method disclosed herein, but that the invention include all embodiments falling within the scope of the appended claims. | Document generation and delivery system that allows a user to download a plurality of sets of data to a document preparation system. The document preparation system has a memory that stores pre-defined forms with a plurality of fields. The downloaded data begins with a definition of the order in which data will be sent for use in filling in the fields of a form. The data sets are then used to populate fields in the form thereby generating documents to be transmitted via facsimile to a plurality of destinations. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a link-member swinging apparatus which includes an actuator for swinging a link member.
2. Related Art Statement
There is known a reciprocating apparatus which is employed in each of various sorts of mechanical drive systems and which reciprocates a drive lever or a drive shaft belonging to the each drive system. For example, FIG. 12 shows a known reciprocating apparatus 110 which includes a stepper motor 112 as an electric actuator; a drive gear 114 fixed to an output shaft of the motor 112; a sector gear 118 meshed with the drive gear 114; and a drive shaft 116 which belongs to a mechanical drive system and which is fixed to the sector gear 118, or a drive lever 119 which belongs to a mechanical drive system and which is pivotally connected to one end portion of the sector gear 118. The stepper motor 112 is first rotated clockwise, subsequently is stopped for a very short time, then is rotated counterclockwise, and is stopped again for a very short time, and those actions are repeated. Thus, the stepper motor 112 reciprocates the drive lever 119 or the drive shaft 116 via the sector gear 118.
In the case where the mechanical drive system to which the drive lever 119 or the drive shaft 106 belongs has a great mass, i.e., a great inertia, when the sector gear 118 is stopped after being rotated, e.g., clockwise by the stepper motor 112, the stepper motor 112 is subjected to impact or vibration due to the great inertia of the drive system via the sector gear 118. In particular, in the case where the drive lever 119 of the reciprocating apparatus 110 laterally reciprocates, e.g., a needle bar of a zigzag sewing machine, at a high speed, the stepper motor 112 is subjected to a great impact or a large vibration due to the great inertia of the drive system including the needle bar. This leads to unstable stitch positions where a sewing needle attached to the needle bar penetrates a work-sheet such as a febric or a leather, or unstable sewing widths over which the needle is laterally reciprocated. Thus, irregular zigzag stitches are formed on the work-sheet. In addition, when the stepper motor 112 is rotated in the opposite direction a very short time after being stopped, the motor 112 may loose its synchronism.
The above problems may be solved by keeping the stepper motor 112 stopped for a long time sufficient for the vibration thereof resulting from the stopping thereof to dissipate substantially completely. In this case, however, the speed of lateral reciprocation of the needle bar cannot, be increased.
Meanwhile, it has been practiced to minimize the vibration of the stepper motor 112 at the time of being stopped, by applying permanently a certain frictional resistance to the mechanical drive system, or applying a certain additional load to reduce the vibration of the motor 112. In either case, however, the stepper motor 112 must be a larger-size one which can produce an additional torque to bear the frictional resistance or the additional load. This leads to increasing the production cost of the zigzag sewing machine.
SUMMARY OF THE INVENTION
It is therefore an object of the present invention to provide a link-member swinging apparatus which quickly absorbs vibration of a link member when the swinging of the link member is stopped, and which has a simple construction.
It is another object of the present invention to provide a sewing machine including the above link-member swinging apparatus.
It is another object of the present invention to provide a swing-link apparatus which quickly absorbs vibration of a swing link when the swinging of the swing link is stopped.
It is another object of the present invention to provide a reciprocal apparatus which quickly absorbs vibration of a reciprocative member when the reciprocation of the reciprocative member is stopped.
It is another object of the present invention to provide a zigzag sewing machine which quickly absorbs vibration of a needle bar when the reciprocation of the needle bar is stopped.
The present invention provides a link-member swinging apparatus, a sewing machine, a swing-link apparatus, a reciprocal apparatus, and a zigzag sewing machine which have one or more of the technical features that are described below in respective paragraphs given parenthesized sequential numbers (1) to (22). Any technical feature which includes another technical feature shall do so by referring, at the beginning, to the parenthesized sequential number given to that technical feature. Thus, two or more of the following technical features may be combined, if appropriate. Each technical feature may be accompanied by a supplemental explanation, as needed. However, the following technical features and the appropriate combinations thereof are just examples to which the scope of the present invention is by no means limited.
(1) According to a first feature of the present invention, there is provided a link-member swinging apparatus for reciprocatively swinging a link member while keeping a fulcrum portion of the link member at substantially a predetermined location, comprising an actuator which is operatively connected to an input portion of the link member, the input portion of the link member being distant from the fulcrum portion thereof in a lengthwise direction of the link member; and a supporting device which elastically supports the fulcrum portion of the link member, while permitting the fulcrum portion to be elastically moved from a reference position thereof in a direction intersecting the lengthwise direction of the link member. The supporting device may be one which elastically supports the fulcrum portion of the link member, while permitting the fulcrum portion to be elastically moved from the reference position thereof in the lengthwise direction of the link member. The actuator may be provided by a stepper motor that can be precisely controlled with respect to its rotation position. The fulcrum portion of the link member is supported by the supporting device such that the link member is reciprocatively swung. When the actuator operatively connected to the input portion of the link member is repetitively operated forward and backward, the link member is reciprocatively swung. In the case where a connection lever of a mechanical drive system, such as a needle-bar reciprocating device or a work-sheet feeding device, is connected to a portion of the link member, the connection lever is reciprocatively moved by the link member that is reciprocatively swung by the actuator. Thus, the needle-bar reciprocating device accurately reciprocates a needle bar over a predetermined stroke, or the work-sheet feeding device accurately reciprocates a feed member over a predetermined stroke. When the swinging of the link member is stopped by the actuator between each of the repetitive forward movements of the link member and a following one of the repetitive backward movements of the same and/or between each of the repetitive backward movements of the link member and a following one of the repetitive forward movements of the same, the link member is subjected to the inertia force of the link member itself and the mechanical drive system, in a certain direction. Consequently the link member is caused to vibrate, i.e., slightly swing, about the fulcrum portion thereof. The supporting device permits the fulcrum portion of the link member to be elastically moved from its reference position, such that the portion of the link member to which the mechanical drive system is connected is substantially prevented from being vibrated. Thus, the needle bar or the feed member is substantially prevented from being vibrated. That portion of the link member may be one of lengthwise opposite end portions of the link member. Since the vibration of the link member is effectively prevented, the speed of swinging of the link member can be increased. In addition, according to the present invention, no additional load such as a friction resistance is applied to the link member, a small-size actuator may be employed in the present swinging apparatus. In the case where a stepper motor is employed as the actuator, the stepper motor is effectively prevented from loosing its synchronism.
(2) According to a second feature of the present invention that includes the first feature (1), the fulcrum portion of the link member comprises a bifurcate end portion, and the supporting device comprises a frame; an eccentric member which includes an axial portion which is pivotally supported by the frame such that the axial portion extends in a direction perpendicular to a swing plane in which the link member is reciprocatively swung; and an eccentric portion which is eccentric with an axis line of the axial portion and which is engaged with the bifurcate end portion of the link member such that the eccentric portion is fitted in an inner space of the bifurcate end portion; and a leaf spring whose one end portion is fixed to the axial portion of the eccentric member such that the leaf spring extends in a direction perpendicular to the axis line of the axial portion, and whose other end portion is engaged with the frame. When the swinging of the link member is stopped by the actuator, the eccentric portion of the eccentric member is rotated with the axial portion thereof by the bifurcate end portion of the link member. Consequently the leaf spring is elastically deformed. This elastic deformation of the leaf spring effectively prevents the vibration of the link member.
(3) According to a third feature of the present invention that includes the first feature (1), the fulcrum portion of the link member comprises a bifurcate end portion, and the supporting device comprises a frame having a hole; an eccentric member which includes an axial portion which is pivotally supported by the frame such that the axial portion extends in a direction perpendicular to a swing plane in which the link member is reciprocatively swung; and an eccentric portion which is eccentric with an axis line of the axial portion and which is engaged with the bifurcate end portion of the link member such that the eccentric portion is fitted in an inner space of the bifurcate end portion; and an annular elastic member which is fixed to an outer circumferential surface of the axial portion of the eccentric member and which is fixed to an inner circumferential surface of the hole of the frame. When the swinging of the link member is stopped by the actuator, the eccentric portion of the eccentric member is rotated with the axial portion thereof by the bifurcate end portion of the link member. Consequently the annular elastic member is elastically deformed in a circumferential direction thereof. This elastic deformation of the annular elastic member effectively prevents the vibration of the link member.
(4) According to a fourth feature of the present invention that includes the first feature (1), the fulcrum portion of the link member comprises a bifurcate end portion, and the supporting device comprises a frame having a hole; an eccentric member which includes an axial portion which is pivotally supported by the frame such that the axial portion extends in a direction perpendicular to a swing plane in which the link member is reciprocatively swung; and an eccentric portion which is eccentric with an axis line of the axial portion and which is engaged with the bifurcate end portion of the link member such that the eccentric portion is fitted in an inner space of the bifurcate end portion; a plate member whose one end portion is fixed to the axial portion of the eccentric member such that the plate member extends in a direction perpendicular to the axis line of the axial portion; and a pair of elastic members which cooperate with each other to sandwich the other end portion of the plate member and which elastically connect the plate member to the frame. When the swinging of the link member is stopped by the actuator, the eccentric portion of the eccentric member is rotated with the axial portion thereof by the bifurcate end portion of the link member. Consequently the plate member is rotated and one of the two elastic members against which the plate member is rotated is elastically deformed or compressed. This elastic compression of the one elastic member effectively prevents the vibration of the link member.
(5) According to a fifth feature of the present invention that includes the first feature (1), the fulcrum portion of the link member comprises a bifurcate end portion, and the supporting device comprises a frame; an axis member which is supported by the frame such that the axis member extends in a direction perpendicular to a swing plane in which the link member is reciprocatively swung; an annular elastic member which is fitted on the axis member; and a sleeve member which is fitted on the annular elastic member and which is fitted in an inner space of the bifurcate end portion of the link member. When the swinging of the link member is stopped by the actuator, the bifurcate end portion of the link member is slightly vibrated. Consequently the annular elastic member is elastically deformed or compressed via the sleeve member. This elastic compression of the annular elastic member effectively prevents the vibration of the link member.
(6) According to a sixth feature of the present invention that includes the first feature (1), the supporting device comprises a frame; a first axis member which extends in a direction perpendicular to a swing plane in which the link member is reciprocatively swung, and which is pivotally connected to the fulcrum portion of the link member; a second axis member which is pivotally supported by the frame such that the second axis member extends parallel to the first axis member; and a connection link which includes an elastic member incorporated in an intermediate portion thereof and which elastically connects the first and second axis members to each other. When the swinging of the link member is stopped by the actuator, the first axis member pivotally connected to the fulcrum portion of the link member is slightly vibrated relative to the second axis member pivotally supported by the frame, via the elastic member of the connection link. Consequently the elastic member of the connection link is elastically deformed. This elastic deformation of the elastic member effectively prevents the vibration of the link member.
(7) According to a seventh feature of the present invention that includes the first feature (1), the supporting device comprises a frame; a first axis member which extends in a direction perpendicular to a swing plane in which the link member is reciprocatively swung, and which is pivotally connected to the fulcrum portion of the link member; a second axis member which is pivotally supported by the frame such that the second axis member extends parallel to the first axis member; a connection link which connects the first and second axis members to each other; and a leaf spring whose one end portion is fixed to the second axis member such that the leaf spring extends in a direction perpendicular to the second axis member, and whose other end portion is engaged with the frame. When the swinging of the link member is stopped by the actuator, the first axis member pivotally connected to the fulcrum portion of the link member is slightly vibrated relative to the second axis member pivotally supported by the frame, via the connection link. Consequently the leaf spring fixed to the connection link is elastically deformed. This elastic deformation of the leaf spring effectively prevents the vibration of the link member.
(8) According to an eighth feature of the present invention, there is provided a sewing machine comprising a needle bar to which a sewing needle is attached; and a needle-bar reciprocating device comprising a link member operatively connected to the needle bar, and a link-member swinging apparatus according to claim 1, and the link-member swinging apparatus laterally reciprocates the needle bar, by reciprocatively swinging the link member operatively connected to the needle bar. When the swinging of the link member is stopped by the actuator, the fulcrum portion of the link member that is elastically supported by the supporting device is permitted to be elastically moved from its reference position. Thus, the portion of the link member to which the needle bar is connected is effectively prevented from being vibrated. Thus, the sewing needle held by the needle holder can be stably stopped at respective stitch positions at opposite ends of a predetermined reciprocal stroke, and additionally the speed of lateral reciprocation of the needle can be increased.
(9) According to a ninth feature of the present invention, there is provided a swing-link apparatus, comprising a frame; a swing link which is engaged via an axis member with the frame such that the swing link is swingable relative to the frame; a drive device which is supported by the frame, which is connected to an input portion of the swing link that is distant from the axis member, and which is repetitively operated forward and backward such that the drive device is kept still for at least one of a first time duration between each of the repetitive forward operations thereof and a following one of the repetitive backward operations thereof and a second time duration between each of the repetitive backward operations thereof and a following one of the repetitive forward operations thereof, so that the repetitive forward and backward operations of the drive device reciprocatively swing the swing link about an axis line of the axis member; and a restoring device which is provided between the frame and a fulcrum portion of the swing link that is engaged with the axis member, which permits the fulcrum portion of the swing link to be moved from a reference position of the fulcrum portion, and which applies a restoring force to the fulcrum portion in a direction in which the fulcrum portion is moved back to the reference position thereof.
(10) According to a tenth feature of the present invention that includes the ninth feature (9), the restoring device has a vibration characteristic which reduces vibration of the swing link that is temporarily produced when the drive device is stopped and kept still for the at least one of the first and second time durations.
(11) According to an eleventh feature of the present invention that includes the ninth or tenth feature (9) or (10), the drive device is kept still for each of the first and second time durations.
(12) According to a twelfth feature of the present invention that includes any one of the ninth to eleventh features (9) to (11), the swing link comprises a drive link which includes an output portion which is distant from the axis member and which is adapted to reciprocate an object.
(13) According to a thirteenth feature of the present invention that includes any one of the ninth to twelfth features (9) to (12), the restoring device comprises a pivotable member which is supported by the frame such that the pivotable member is pivotable about an axis line thereof, the axis member being secured to the pivotable member such that the axis member is eccentric with the axis line of the pivotable member; and a torque applying device which includes an elastic member and which utilizes an elastic force of the elastic member for applying a torque to pivot the pivotable member toward a reference rotation position thereof corresponding to the reference position of the fulcrum portion of the swing link.
(14) According to a fourteenth feature of the present invention that includes the thirteenth feature (13), the elastic member comprises a spring member whose one end portion is fixed to the pivotable member such that the spring member extends radially outwardly from the pivotable member, and whose other end portion is engaged with the frame.
(15) According to a fifteenth feature of the present invention that includes any one of the ninth to fourteenth features (9) to (14), the axis member is fixed to the frame and the restoring device comprises an elastic member which is provided between the axis member and the fulcrum portion of the swing link.
(16) According to a sixteenth feature of the present invention, there is provided a reciprocal apparatus, comprising a frame; a reciprocative member which is supported by the frame such that the reciprocative member is reciprocatively moved relative to the frame; a drive device which is supported by the frame and which is repetitively operated forward and backward such that the drive device is kept still for at least one of a first time duration between each of the repetitive forward operations thereof and a following one of the repetitive backward operations thereof and a second time duration between each of the repetitive backward operations thereof and a following one of the repetitive forward operations thereof; a transmitting device which operatively connects the drive device and the reciprocative member to each other and which transmits a drive force of the drive device to the reciprocative member; and a vibration absorbing device which includes an elastic member which separates the transmitting device into a first portion on a side of the reciprocative member and a second portion on a side of the drive device, the elastic member absorbing vibration of a movable portion of the drive device and vibration of the second portion, so that vibration of the reciprocative member is smaller than the vibration of the movable portion that is temporarily produced when the drive device is stopped and kept still for the at least one of the first and second time durations.
(17) According to a seventeenth feature of the present invention, there is provided a zigzag sewing machine, comprising a machine frame; a needle bar which is supported by the machine frame such that the needle bar is reciprocatively moved in each of an axial direction thereof and a transverse direction thereof substantially perpendicular to the axial direction; an electric motor which is supported by the machine frame and which is repetitively operated forward and backward such that the electric motor is kept still for at least one of a first time duration between each of the repetitive forward operations thereof and a following one of the repetitive backward operations thereof and a second time duration between each of the repetitive backward operations thereof and a following one of the repetitive forward operations thereof; a transmitting device which operatively connects the electric motor and the needle bar to each other and which transmits a drive force of the electric motor to the needle bar so that the needle bar is reciprocatively moved in the transverse direction thereof; and a vibration absorbing device which includes an elastic member which separates the transmitting device into a first portion on a side of the needle bar and a second portion on a side of the electric motor, the elastic member absorbing vibration of the second portion and vibration of a movable portion of the electric motor, such that vibration of the needle bar in the transverse direction thereof is smaller than vibration of the movable portion that is temporarily produced in the transverse direction when the movable portion is stopped and kept still for the at least one of the first and second time durations.
(18) According to an eighteenth feature of the present invention that includes the seventeenth feature (17), the transmitting device comprises a rod which is supported by the machine frame such that the rod extends in a substantially horizontal direction and is movable in an axial direction thereof; a needle-bar support frame which is connected to one of opposite end portions of the rod and which supports the needle bar such that the needle bar is movable in the axial direction thereof; a swing link which is engaged via an axis member with the machine frame such that the swing link is swingable relative to the machine frame and which includes an output portion which is distant from the axis member and which is operatively connected to the other end portion of the rod; and a connecting device which connects an output portion of the movable portion of the electric motor, to an input portion of the swing link that is distant from the axis member, so as to transmit the driving force of the electric motor to the input portion of the swing link, and the vibration absorbing device comprises a restoring device which is provided between the machine frame and a fulcrum portion of the swing link that is engaged with the axis member, which permits the fulcrum portion of the swing link to be moved from a reference position of the fulcrum portion, and which applies a restoring force to the fulcrum portion in a direction in which the fulcrum portion is moved back to the reference position thereof.
(19) According to a nineteenth feature of the present invention that includes the eighteenth feature (18), the restoring device comprises a pivotable member which is supported by the machine frame such that the pivotable member is pivotable about an axis line thereof, the axis member being secured to the pivotable member such that the axis member is eccentric with the axis line of the pivotable member; and a torque applying device which utilizes an elastic force of the elastic member for applying a torque to pivot the pivotable member toward a reference rotation position thereof corresponding to the reference position of the fulcrum portion of the swing link.
(20) According to a twentieth feature of the present invention that includes the seventeenth feature (17), the transmitting device comprises a rod which is supported by the machine frame such that the rod extends in a substantially horizontal direction and is movable in an axial direction thereof; a needle-bar support frame which is connected to one of opposite end portions of the rod and which supports the needle bar such that the needle bar is movable in the axial direction thereof; a swing link which is engaged via an axis member with the machine frame such that the swing link is swingable relative to the machine frame and which includes an output portion which is distant from the axis member and which is operatively connected to the other end portion of the rod; and a connecting device which connects an output portion of the movable portion of the electric motor, to an input portion of the swing link that is distant from the axis member, so as to transmit the driving force of the electric motor to the input portion of the swing link, and the vibration absorbing device comprises a restoring device comprises the elastic member which is provided between the output portion of the swing link and the other end portion of the rod.
(21) According to a twenty-first feature of the present invention that includes any one of the eighteenth to twentieth features (18) to (20), the electric motor comprises, as the movable portion thereof, a rotor which is rotatable about an axis line thereof, and an output shaft which is rotatable with the rotor, and the connecting device comprises a crank arm whose one end portion is fixed to the output shaft as the output portion of the movable portion and whose other end portion is connected to the input portion of the swing link such that the crank arm is pivotable about an axis line parallel to an axis line of the output shaft.
(22) According to a twenty-second feature of the resent invention that includes the twenty-first feature (21), one of the swing link and the machine frame supports the axis member as a first axis member and the other of the swing link and the machine frame includes a first recessed portion which is engaged with the first axis member, one of the other end portion of the crank arm and the input portion of the swing link supports a second axis member parallel to the axis line of the output shaft, and the other of the other end portion of the crank arm and the input portion of the swing link includes a second recessed portion which is engaged with the second axis member, and one of the first and second recessed portions defines a circular hole having a circular cross section and the other of the first and second recessed portions defines an elongate recess which is elongate in a direction substantially parallel to a straight line perpendicular to each of the respective axis lines of the first and second axis members.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and optional objects, features, and advantages of the present invention will be better understood by reading the following detailed description of the preferred embodiments of the invention when considered in conjunction with the accompanying drawings, in which:
FIG. 1 is a front elevation view of a sewing machine including a link-member swinging apparatus to which the present invention is applied;
FIG. 2 is a rear elevation view of the link-pivoting apparatus of FIG. 1;
FIG. 3 is a longitudinal cross section of a link supporting device of the link-member swinging apparatus of FIG. 1, taken along Line 3--3 shown in FIG. 1;
FIG. 4 is a schematic perspective view of the link supporting device of FIG. 3;
FIG. 5A is a view for explaining vibration of a link member when a drive motor of the link-member swinging apparatus of FIG. 1 is stopped;
FIG. 5B is a rear elevation view of a portion of the link supporting device of FIG. 3, for explaining elastic deformation of a leaf spring of the link supporting device;
FIG. 6 is a rear elevation view of a link supporting device of another link-member swinging apparatus as a second embodiment of the present invention;
FIG. 7 is a rear elevation view of a link supporting device of another link-member swinging apparatus as a third embodiment of the present invention;
FIG. 8 is a front elevation view of a link supporting device of another link-member swinging apparatus as a fourth embodiment of the present invention;
FIG. 9 is a front elevation view of a link supporting device of another link-member swinging apparatus as a fifth embodiment of the present invention;
FIG. 10 is a front elevation view of a link supporting device of another link-member swinging apparatus as a sixth embodiment of the present invention;
FIG. 11 is a front elevation view of a link supporting device of another link-member swinging apparatus as a seventh embodiment of the present invention; and
FIG. 12 is a front elevation view of a conventional link-member swinging apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 to 4 and FIGS. 5A and 5B, there will be described a link-member swinging apparatus 10 for reciprocatively swinging a link member 14 and thereby reciprocating a needle-bar support device 4 employed in an electronic zigzag sewing machine 1. The link-member swinging apparatus 10 and the zigzag sewing machine 1 embody the present invention.
First, the needle-bar support device 4 will be described. However, the support device 4 is well known in the art, it will be described briefly.
The sewing machine 1 includes an arm portion 3 in a free end portion of which a needle-bar support-frame member 5 having a generally U-shaped configuration in its front elevation view is provided. A needle bar 7 which vertically extends is supported by the support-frame member such that the needle bar 7 can be reciprocated up and own. A sewing needle 8 is attached to a lower end of the needle bar 7.
The needle-bar support-frame member 5 is fixed to one of opposite end portions of a shaft 6 which horizontally extends in an intermediate portion of the arm portion 3. The shaft 6 is supported by a framework 2 of the sewing machine 1 via two bearings 50 such that the shaft 6 is horizontally slideable. A connection member 51 which is fixed to the other end portion of the shaft 6, is pivotally connected to one of opposite end portions of a connection lever 9 via a pin 52. The other end portion of the connection lever 9 is pivotally connected via a pin 53 to the link member 14 which is reciprocatively pivoted by the link-member swinging apparatus 10. When the link member 14 is reciprocatively pivoted, the needle-bar support-frame member 5 is simultaneously reciprocated via the link lever 9. Thus, the needle bar 7 is horizontally reciprocated as shown in two-dot chain lines in FIG. 1. While the needle bar 7 is horizontally reciprocated, it is also vertically reciprocated so that the sewing needle 8 cooperates with a thread-loop catcher (not shown) provided in a bed portion of the sewing machine 1, to form zigzag stitches on a work sheet such as a cloth or a leather. The manner in which the needle bar 7 is vertically reciprocated will not be described because it is well known in the art.
Next, there will be described the link-member winging apparatus 10 which is provided in a columnar portion of the sewing machine 1.
A base plate 11 is fixed to the frame 2 of the column portion of the sewing machine 1, and a stepper motor 12 as a drive source is fixed to a rear surface of the base plate 11. An output shaft 12a of the drive motor 12 extends through the thickness of the base plate 11, from the rear side of the plate 11 to the front side thereof. A base portion of a drive lever 13 is fixed to the output shaft 12a, and an end portion of the drive lever 13 is pivotally connected via a pin 13a to a near-end portion of the link member 14 that is near to the upper end of the same 14. The near-end portion of the link member 14 can be the as an intermediate portion of the same 14 as seen in a longitudinal direction thereof. The near-end portion will be referred to as the "input" portion 14b. The link member 14 is connected, at the upper end portion thereof, to one end portion of the connection lever 9.
As the drive motor 12 is reciprocatively driven or rotated clockwise and counterclockwise, the upper end portion of the drive lever 13 is reciprocatively pivoted clockwise and counterclockwise, so that the link member 14 is reciprocatively pivoted clockwise and counterclockwise about a lower end portion thereof.
Next, there will be described a link supporting device 20 which supports the lower end portion of the link member 14, i.e., fulcrum portion of the same 14.
The fulcrum portion of the link member 14 includes a bifurcate end portion 14a. The base plate 11 has a through-hole 11a at a position corresponding to the bifurcate portion 14a. A cylindrical sleeve member 21 is fitted in the through-hole 11a, and an eccentric axis member 22 is fitted in the sleeve member 21 such that the eccentric axis member 22 is pivotable about an axis line, S, which is perpendicular to a plane in which the link member 14 is swung.
As shown in FIGS. 3 and 4, the eccentric axis member 22 includes a pivotable axis portion 22a which is supported by the base plate 11 such that the pivotable axis portion 22a is pivotable about the axis line S; and an eccentric axis portion 22b which is integrally formed with the pivotable axis portion 22a.
The eccentric axis portion 22b is located on the front side of the base plate 11, and an axis line of the eccentric axis portion 22b is deviated from the axis line S of the pivotable axis portion 22a by a predetermined distance, δ, in a vertically upward direction. The bifurcate portion 14a of the link member 14 is externally engaged with the eccentric axis portion 22b of the eccentric axis member 22.
Meanwhile, an upper end portion of a rectangular leaf spring 23 which vertically extends is fixed to a rear end portion of the pivotable axis portion 22a.
A pair of adjustable blocks 25, 26 each of which has a generally L-shaped configuration in its plane view are fixed via bolts 27 to the base plate 11 at respective positions below the pivotable axis portion 22a. The two adjustable blocks 25, 26 have respective pairs of elongate holes 25a, 26a which are horizontally elongate and through which the bolts 27 are fastened to the base plate 11. Thus, the position of each of the blocks 25, 26 is adjustable in a horizontal direction. The two blocks 25, 26 have respective elongate projections 25b, 26b which project toward each other from respective lower end portions of the blocks 25, 26 and which cooperate with each other to pinch, with a certain pressure, a lower end portion of the leaf spring 23. The two projections 25b, 26b have respective substantially half-cylindrical engaging surfaces which engage opposite elongate surfaces of the lower end portion of the leaf spring 23, respectively. Thus, the two projections 25b, 26b contact the leaf spring 23 via respective peak "lines" (not "points") of the half-cylindrical engaging surfaces thereof. The leaf spring 23 has a predetermined thickness, and has an elastic characteristic that is so predetermined as to reduce vibration of the link member 14, as described later.
In a normal condition in which no external force is applied to the leaf spring 23, the spring 23 straightly and vertically extends without any strain, as shown in FIG. 4. Therefore, the eccentric axis member 22 takes a normal attitude, as shown in FIGS. 2 and 4, in which the center line of the eccentric axis portion 22b is positioned right above the center line S of the pivotable axis portion 22a. Thus, the bifurcate end portion 14a of the link member 14 that is externally engaged with the eccentric axis portion 22b is positioned at a predetermined reference position corresponding to the center line of the eccentric axis portion 22b in a substantially horizontal direction. Therefore, when the drive motor 12 is reciprocatively swung, the link member 14 is reciprocatively pivoted about the center line of the eccentric axis portion 22b via the bifurcate portion 14a thereof.
Next, there will be described the operation and advantages of the link-member swinging apparatus 10 constructed as described above.
When the electronic sewing machine 1 carries out the zigzag sewing operation, the drive motor 12 is reciprocatively rotated by an angle corresponding to the width of the zigzag pattern to be formed, i.e., the distance by which the needle bar 7 is reciprocatively moved laterally. Therefore, the drive lever 13 is reciprocatively pivoted and, as shown in FIG. 5A, the link member 14A indicated in solid line is reciprocatively swung about the eccentric axis portion 22b, symmetrically with respect to a vertical center line, m. Accordingly, the needle-bar support-frame member 5 is horizontally reciprocated via the connection lever 9 and the shaft 6, so that the needle bar 7 is reciprocated and the zigzag stitches are formed on the work sheet. Since the length of the drive lever 13 is smaller than that of the link member 14, the position of the link member 14 is slightly moved in a vertical direction, when the link member 14 is swung by the drive lever 13. This slight vertical movement of the link member 14 is allowed by sliding of the link member 14 on inner flat surfaces of the bifurcate end portion 14a within an inner space of the same 14a.
When the rotation of the drive motor 12 is stopped to allow the sewing needle 8 to penetrate the work sheet and form a stitch thereon, the swinging of the link member 14 is also stopped via the drive lever 13.
However, in the case where the needle-bar support device 4 and the link member 14 itself have a great mass, i.e., a great inertia, the link member 14 receives a shock due to the inertia, when it is stopped. Accordingly, the link member 14 is vibrated, i.e., slightly swung about the bifurcate end portion 14a thereof, i.e., the fulcrum portion thereof.
The bifurcate end portion 14a of the link member 14 is engaged with the eccentric axis portion 22b, and an angular position of the pivotal axis portion 22a or the eccentric axis portion 22b is defined by the leaf spring 23 only, as described above. Therefore, as shown in FIG. 5A, the link member 14B indicated in two-dot chain line is vibrated, i.e., swung about the input portion 14b thereof in the same plane as the plane in which the link member 14A indicated in solid line is swung about the bifurcate end portion 14a. FIG. 5A exaggerates the vibration of the link member 14B, for illustration purposes only, though, in fact, the vibration is very small.
Thus, the bifurcate end portion 14a is vibrated, and the eccentric axis portion 22b alternatively receives a leftward force and a rightward force each for a very short time duration. For example, when the eccentric axis portion 22b receives a leftward force, the eccentric axis member 22 is pivoted counterclockwise as seen in FIG. 1, and accordingly the pivotable axis portion 22a is pivoted clockwise as seen in FIG. 5B, so that the leaf spring 23 is elastically deformed. Since the leaf spring 23 is held by the respectively peak lines of the elongate projections 25b, 26b of the adjustable blocks 25, 26, the entire leaf spring 23 can function, when being elastically deformed, to absorb effectively the vibration of the link member 14. The blocks 25, 26 may have, in place of the respective half-cylindrical projections 25b, 26b, respective wedge-like projections at which the blocks 25, 26 hold the leaf spring 23.
On the other hand, when the eccentric axis portion 22b receives a rightward force because of the vibration of the bifurcate portion 14a, the eccentric axis member 22 is pivoted clockwise as seen in FIG. 1, and accordingly the pivotable axis portion 22a is pivoted counterclockwise as seen in FIG. 5B, so that the leaf spring 23 is elastically deformed. Thus, the vibration of the link member 14 can be quickly and effectively attenuated by the elastic deformation of the leaf spring 23. The link supporting device 20 enjoys a simple construction.
Since the vibration of the lower end portion (i.e., the bifurcate end portion 14a) of the link member 14 is minimized when the swinging of the link member 14 is stopped, the vibration of the connection lever 9, the shaft 6, and the needle-bar support-frame member 5 that are connected to the upper end portion of the link member 14 is also minimized when the horizontal motion of those members 9, 6, 5 is stopped.
Therefore, in the state in which the sewing needle 8 is sticking the work sheet, the needle 8 is prevented from being horizontally vibrated. Thus, the sewing needle 8 can form neat zigzag stitches. In addition, since the vibration of the sewing needle 8 is minimized, the needle 8 can be reciprocated at a high speed. Accordingly, the speed of sewing of the sewing machine 1 can be increased. Moreover, no additional load such as a friction resistance is applied to the link member 14 while the link member 14 is reciprocatively swung by the drive motor 12. Thus, the drive motor 12 enjoys a small size or capacity. The drive motor 12 that is provided by a stepper motor, is prevented from losing synchronism when the rotation thereof is resumed.
FIG. 6 shows a second embodiment of the present invention, in which the link supporting device 20 shown in FIG. 1 is partly modified to a link supporting device 20A.
A bifurcate end portion 14a provided by a lower end portion of a link member 14 is externally engaged with an eccentric axis portion 22b of an eccentric axis member 22A, and a pivotable axis portion 22c of the eccentric axis member 22A is pivotally supported by a base plate 11 via an annular elastic member 30 formed of a hard rubber. The annular elastic member 30 is fixed to an outer surface of the pivotable axis portion 22c by adhesion with an adhesive, and is fixed to a through-hole 11a formed through a thickness of the base plate 11, by adhesion with an adhesive.
When rotation of a drive motor 12 is stopped, the link member 14 vibrates, and the bifurcate end portion 14a thereof rotates the eccentric axis portion 22b of the eccentric axis member 22A. Therefore, the pivotable axis portion 22c is rotated. Consequently the annular elastic member 30 is elastically deformed in a circumferential direction thereof. Thus, the vibration of the link member 14 is effectively attenuated by the elastic deformation of the annular member 30. The link supporting device 20A enjoys a simple construction.
FIG. 7 shows a third embodiment of the present invention, in which the link supporting device 20 shown in FIG. 1 is partly modified to a link supporting device 20B.
A bifurcate end portion 14a provided by a lower end portion of a link member 14 is externally engaged with an eccentric axis portion 22b of an eccentric axis member 22B, and a pivotable axis portion 22d of the eccentric axis member 22B is pivotally supported by a base plate 11. An upper end portion of a plate member 32 formed of a hard material such as a metal or a resin is fixed to the pivotable axis portion 22d. A lower end portion of the plate member 32 is elastically pinched and supported by a pair of elastic members 33 each of which is formed of a hard rubber and which are adhered to respective inner surfaces of a pair of blocks 25B, 26B each of which has a generally L-shaped configuration in its plan view and is fixed to a back surface of the base plate 11 via bolts.
When rotation of a drive motor 12 is stopped, the link member 14 vibrates, and the bifurcate end portion 14a thereof rotates the eccentric axis portion 22b of the eccentric axis member 22B. Therefore, the pivotable axis portion 22d is rotated. Consequently the plate member 32 is moved, and one of the two elastic members 33 is elastically deformed by being compressed by the plate member 32 being moved. Thus, the vibration of the link member 14 is effectively attenuated by the elastic deformation of the one elastic member 33. The link supporting device 20B enjoys a simple construction.
FIG. 8 shows a fourth embodiment of the present invention, in which the link supporting device 20 shown in FIG. 1 is partly modified to a link supporting device 20C.
A bifurcate end portion 14a provided by a lower end portion of a link member 14 is externally engaged with a cylindrical sleeve member 35 formed of a metal. An annular elastic member 36 formed of a hard rubber is fitted in an inner cylindrical space of the sleeve member 35, and is fitted on an axis member 37 which is fixed to a base plate 11 such that the axis member 37 extends horizontally frontward.
When rotation of a drive motor 12 is stopped, the link member 14 vibrates, and the bifurcate end portion 14a thereof also vibrates. Consequently the sleeve member 35 is moved relative to the axis member 37, and a portion of the annular elastic member 36 is elastically deformed by being compressed. Thus, the vibration of the link member 14 is effectively attenuated by the elastic deformation of the annular member 36. The link supporting device 20C enjoys a simple construction.
FIG. 9 shows a fifth embodiment of the present invention, in which the link supporting device 20 shown in FIG. 1 is partly modified to a link supporting device 20D.
A lower end of a link member 14D is pivotally connected to a link-support axis member 38 which extends in a direction perpendicular to a base plate 11. A base axis member 39 is pivotally supported by the base plate 11 such that the base axis member 39 extends horizontally frontward parallel to the link-support axis member 38. A connection link 40 which includes, in an intermediate portion thereof, a U-shaped leaf spring 41 as an elastic member elastically connects between the two axis members 38, 39.
When rotation of a drive motor 12 is stopped, the link member 14D vibrates, and the link-support axis member 38 pivotally connected to the link member 14D also vibrates with elastic deformation of the leaf spring 41 of the connection link 40 elastically connected to the base axis member 39. Thus, the vibration of the link member 14D is effectively attenuated by the elastic deformation of the leaf spring 41. The link supporting device 20D enjoys a simple construction. The connection link 40 may include, in an intermediate portion thereof, an elastic member different from the leaf spring 41, such as a plate-like rubber member.
FIG. 10 shows a sixth embodiment of the present invention, in which the link supporting device 20 shown in FIG. 1 is partly modified to a link supporting device 20E.
A lower end of a link member 14E is pivotally connected to a link-support axis member 43 which extends in a direction perpendicular to a base plate 11. A base axis member 44 is pivotally supported by the base plate 11 such that the base axis member 44 extends horizontally through a thickness of the base plate 11, parallel to the link-support axis member 43. A connection link 45 connects between the two axis members 43, 44. An upper end of a leaf spring 46 which vertically extends is fixed to a rear end portion of the base axis member 44, and a lower end portion of the leaf spring 46 is pinched by a pair of blocks 25E, 26E each of which has a generally L-shaped configuration in its plan view and is fixed to a back surface of the base plate 11 via bolts.
When rotation of a drive motor 12 is stopped, the link member 14E vibrates, and the link-support axis member 43 pivotally connected to the link member 14E also vibrates with the connection link 45 connected to the base axis member 44. Thus, the vibration of the link member 14E is effectively attenuated by the elastic deformation of the leaf spring 46. The link supporting device 20E enjoys a simple construction.
FIG. 11 shows a seventh embodiment of the present invention, in which the fourth link supporting device 20C shown in FIG. 8 is partly modified to a link supporting device 20F.
An annular portion 14c provided by a lower end portion of a link member 14F is externally engaged with a cylindrical sleeve member 35F formed of a metal. An annular elastic member 36F formed of a hard rubber is fitted in an inner cylindrical space of the sleeve member 35F, and is fitted on an axis member 37F which is fixed to a base plate 11 such that the axis member 37F extends horizontally frontward. The link member 14F has a rectangular hole 14d which is formed through a thickness of a portion thereof near an upper end portion thereof. A square movable member 34 which is fixed to an upper end portion of a drive lever 13 fixed to an output shaft 12a of a stepper motor 12, is slideably fitted in the rectangular hole 14d.
When rotation of the stepper motor 12 is stopped, the link member 14F vibrates, and the annular portion 14c thereof also vibrates. Consequently the sleeve member 35F is moved relative to the axis member 37F, and a portion of the annular elastic member 36F is elastically deformed by being compressed. Thus, the vibration of the link member 14F is effectively attenuated by the elastic deformation of the annular member 36F. The link supporting device 20F enjoys a simple construction.
In the embodiment shown in FIG. 11, an upper end portion of the link member 14F may be connected to the connection lever 9 via the connection link 40 employed in the embodiment shown in FIG. 9. The connection link 40 includes the U-shaped leaf spring 41. In this case, the annular elastic member 36F may be omitted.
The link member 14, 14D, 14E, 14F which is swung by the link-member swinging apparatus 10 may be used to reciprocate horizontally a feed plate or member (not shown) which is employed in a work-sheet feeding device (not shown) of the electronic sewing machine 1. The principle of the present invention may be applied to a looper drive device which drives a looper for catching the needle thread conveyed by the sewing needle 8; or various sorts of link-member swinging apparatuses which swing respective link members employed in various sorts of mechanical drive systems other than those of sewing machines.
It is to be understood that the present invention may be embodied with various changes, improvements, and modifications that may occur to those skilled in the art without departing from the scope and spirit of the invention defined in the appended claims. | A link-member swinging apparatus for reciprocatively swinging a link member while keeping a fulcrum portion of the link member at substantially a predetermined location, including an actuator which is operatively connected to an input portion of the link member, the input portion of the link member being distant from the fulcrum portion thereof in a lengthwise direction of the link member, and a supporting device which elastically supports the fulcrum portion of the link member, while permitting the fulcrum portion to be elastically moved from a reference position thereof in a direction intersecting the lengthwise direction of the link member. | 3 |
PRIORITY
[0001] This application claims priority under 35 U.S.C. § 119 to an application entitled “System And Method For Performing Handover In A Wireless Mobile Communication System” filed in the Korean Intellectual Property Office on Aug. 25, 2005 and assigned Ser. No. 2005-78354,the contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to a wireless mobile communication system, and in particular, to a system and method for performing a handover for a Mobile Station (MS).
[0004] 2. Description of the Related Art
[0005] Provisioning of services with a variety of Quality of Service (QoS) levels at about 100 Mbps to users will be necessary in a future-generation communication system called a 4 th Generation (4G) mobile communication system. The 4G communication system is envisioned as a new communication system that supports user mobility and QoS to Wireless Local Area Network (WLAN) providing relatively high data rates and a Wireless Metropolitan Area Network (WMAN). A major 4G communication system is known as the Institute of Electrical and Electronics Engineers (IEEE) 802.16 communication system.
[0006] With reference to FIG. 1 , the configuration of a multi-cell IEEE 802.16e communication system will be described as one of the IEEE 802.16 communication systems.
[0007] FIG. 1 illustrates the configuration of the typical IEEE 802.16e communication system.
[0008] Referring to FIG. 1 , the IEEE 802.16e communication system has a plurality of cells 100 and 150 , Base Stations (BSs) 110 and 140 having the cells 100 and 150 under their control, respectively, and a plurality of MSs 111 , 113 , 130 , 151 , and 153 .
[0009] The MS 130 is located at the boundary between the cells 100 and 150 , i.e., in a handover region. Thus, support of handover for the MS 130 is equivalent to support of mobility for the MS 130 .
[0010] Since the IEEE 802.16e communication system supports mobility to an MS, it can move from a current BS (i.e. a serving BS) to a neighbor BS.
[0011] The process from selection of the serving BS by the MS until before handover will be described below.
[0012] Upon power-on, the MS monitors a total frequency band and detects a pilot channel signal having the highest pilot Carrier-to-Interference and Noise Ratio (CINR). The MS determines that the BS which sent the pilot channel signal is its serving BS. Then the MS receives pilot signals from the serving BS and neighbor BSs and measures the CINRs of the pilot signals. If the CINR of a neighbor BS is higher than that of the serving BS, the MS operates for a handover to the neighbor BS. This step of measuring the channel status of the serving BS and the neighbor BSs is called scanning. With reference to FIG. 2 , an MS-initiated scanning in the typical IEEE 802.16e communication system will be described.
[0013] FIG. 2 is a diagram illustrating a signal flow for the MS-initiated scanning in the typical IEEE 802.16e communication system.
[0014] A scanning request can be initiated by a BS or an MS. In the former case, the BS may request the MS to scan neighbor BSs in order to distribute its load, while in the latter case, the MS may request scanning to the BS when the CINR of a current channel is lower than a predetermined threshold.
[0015] Referring to FIG. 2 , a first BS 220 (BS # 1 ) is a serving BS which periodically sends a Mobile_Neighbor-Advertisement (MOB_NBR-ADV) message to an MS 200 in step 202 . BS # 1 broadcasts information about a second BS 240 (BS # 2 ) and a third BS 260 (BS # 3 ) by the MOB_NBR-ADV message. The MOB_NBR-ADV message is formatted as defined in the IEEE 802.16e/Document 8 , the contents of which are incorporated herein by reference.
[0016] When the MS 200 desires to scan the neighbor BSs after receiving the MOB_NBR-ADV message, it sends a Mobile_Scanning Interval Allocation-Request (MOB_SCN-REQ) message to BS # 1 in step 204 . The MOB_SCN-REQ has a configuration as defined in the IEEE 802.16e/Document 8 .
[0017] Upon receipt of the MOB_SCN-REQ message, BS # 1 replies with a Mobile_Scanning Interval Allocation-Response (MOB_SCAN-RSP) message containing scanning information (such as scan iteration information, etc.) to the MS 200 in step 206 . The configuration of the MOB_SCN-RSP is also defined in the IEEE 802.16e/Document 8 .
[0018] The MS 200 scans the pilot CINRs of the neighbor BSs for N frames M frames after receiving the MOB_SCN-RSP message in steps 208 and 210 . The parameters M and N are assumed, for convenience sake. How many times the MS 200 is to scan is determined by scan iteration information included in the scanning information.
[0019] The MS 200 reports pilot CINR measurements acquired during the scanning to BS # 1 by a Mobile_Scanning-Report (MOB_SCN-REP) message in step 211 . In step 212 , the MS receives data traffic from BS # 1 during a frame period indicated by interleaving interval information.
[0020] In step 214 through step 218 , the MS 200 repeats the pilot CINR measurement and the data traffic reception a predetermined number of times, i.e., as many times as indicated by the scan iteration information.
[0021] As described above, to support handover in the IEEE 802.16e system, the MS 200 measures the pilot CINRS of the serving BS 220 and the neighbor BSs. If the pilot CINR of the serving BS 220 is lower than that of a neighbor BS 240 or 260 , the MS 200 request a handover (to one of the target BSs 240 or 260 ) to the serving BS 220 .
[0022] Owing to the development of communication technology, MSs demand large-capacity and diverse services. In this context, BSs must satisfy the demand by operating in both a Narrow frequency Band (NB) and a Wide frequency Band (WB). Also, the BSs may use various frequency modes, for example, a combination of Frequency Division Duplex (FDD) and Time Division Duplex (TDD). When a BS uses at least two different frequency bands and/or at least two different frequency modes (i.e., operates in a dual mode), an MS communicating with the corresponding BS must operate the frequency bands and/frequency modes in a similar fashion.
[0023] Accordingly, MSs operating in a dual mode or other similar environment (e.g., the NB and/or WB environments) scan the NB and the WB individually, and/or scan in the individual frequency modes. This results in the increase of scanning time and hardware/software complexity. In addition, the MS cannot receive data traffic during the scanning period. Accordingly, there is a need for a technique for enabling fast, successful handover through efficient scanning of an MS in a communication system using different frequency bands and/or different frequency modes.
SUMMARY OF THE INVENTION
[0024] An object of the present invention is to substantially solve at least the above problems and/or disadvantages and to provide at least the advantages below. Accordingly, the present invention provides a system and method for enabling an MS to efficiently scan in a Broadband Wireless Access (BWA) communication system using different frequency bands and/or different frequency modes.
[0025] The present invention provides a system and method for enabling an MS to perform handover successfully in a BWA communication system using different frequency bands and different frequency modes.
[0026] According to one aspect of the present invention, in a method of performing an MS-initiated scanning in an MS in a wireless mobile communication system having at least two frequency bands with different central frequencies, the MS receives from a serving BS a mobile neighbor advertisement message including information about available radio resources of neighbor BS, transmits a new scanning request message to the serving BS, if the MS determines to measure the CINRs of pilot signals from the serving BS and the neighbor BS, receives from the serving BS a response message for the scanning request message, including information about a BS which has reserved radio resources for a predetermined one of the at least two frequency bands, and measures the CINRs of the pilot signals in the predetermined frequency band.
[0027] According to another aspect of the present invention, in a scanning method in a serving BS in a wireless mobile communication system having at least two frequency bands with different central frequencies, the serving BS transmits a mobile neighbor advertisement message including information about available radio resources of the neighbor BSs, and determines whether radio resources are available for a current frequency band of an MS in the serving BS and the neighbor BS, if determining that scanning is required for the MS. In the absence of the available radio resources, the serving BS requests the neighbor BS to reserve radio resources for the current frequency band of the MS, and receives a response message for the resource reservation request from the neighbor BS. If the response message indicates a successful resource reservation, the serving BS transmits a scanning response message including information about the neighbor BS to the MS.
[0028] According to a further aspect of the present invention, in a scanning method in a BS neighboring a serving BS in a wireless mobile communication system having at least two frequency bands with different central frequencies, the neighbor BS receives a resource reservation request for a first MS from the serving BS and determines whether available radio resources exist for a first frequency band in which the first MS operates currently. In the absence of the available radio resources, the neighbor BS searches for a second MS operating in the first frequency band of the first MS and capable of transitioning to a second frequency band among MSs managed by the neighbor BS. If the second MS is detected, the neighbor BS releases radio resources used in the first frequency band for the second BS by transitioning the second MS to the second frequency band, reserves the released radio resources for the first MS, and transmits information indicating the radio resource reservation to the serving BS.
[0029] According to still another aspect of the present invention, in a method of performing an MS-initiated scanning in an MS in a wireless mobile communication system having at least two different frequency modes, the MS receives from a serving BS a mobile neighbor advertisement message including information about available radio resources of the neighbor BSs, transmits a new scanning request message to the serving BS, if the MS determines to measure the CINRs of pilot signals from the serving BS and the neighbor BS, receives from the serving BS a response message for the scanning request message, including information about a BS which has reserved radio resources for a predetermined one of the at least two frequency modes, and measures the CINRs of the pilot signals in the predetermined frequency mode.
[0030] According to still further of the present invention, in a scanning method in a serving BS in a wireless mobile communication system having two different frequency modes, the serving BS transmits a mobile neighbor advertisement message including information about available radio resources of the neighbor BSs, and determines whether radio resources are available for a current frequency mode of an MS in the neighbor BSs, if determining that scanning is required for the MS. And the serving BS requests the neighbor BS to reserve radio resources for the current frequency mode of the MS, and receives a response message for the resource reservation request from the neighbor BS. If the response message indicates successful resource reservation, the serving BS transmits a scanning response message including information about the neighbor BS to the MS.
[0031] According to yet another aspect of the present invention, in a scanning method in a BS neighboring a serving BS in a wireless mobile communication system having at least two different frequency modes, the neighbor BS receives a radio resource reservation request for a first MS from the serving BS and determines whether available radio resources exist for a first frequency mode in which the first MS currently operates. In the absence of the available radio resources, the neighbor BS searches for a second MS operating in the first frequency mode of the first MS and capable of transitioning to a second frequency mode among MSs managed by the neighbor BS. If the second MS is detected, the neighbor BS releases radio resources used in the first frequency mode for the second BS by transitioning the second MS to the second frequency mode, reserves the released radio resources for the first MS, and transmits information indicating the radio resources reserved for the first MS to the serving BS.
[0032] According to yet further aspect of the present invention, in a wireless mobile communication system having at least two frequency bands each having different central frequencies, a scanning system includes an MS, a serving BS, and a neighbor BS. The MS receives from the serving BS a mobile neighbor advertisement including information about available radio resources of the neighbor BSs, determines whether to measure CINRs of pilot signals received from the serving BS and the neighbor BS, transmits a new scanning request message to the serving BS, if the MS determines to measure the CINRs of the pilot signals, receives a scanning response message for the scanning request message from the serving BS, the response message including information about a BS which has reserved radio resources for a predetermined one of the at least two frequency bands, and measures the CINRs of the pilot signals from the serving BS and the neighbor BS in the predetermined frequency band. The serving BS transmits the mobile neighbor advertisement message, determines whether radio resources are available for a first frequency band in which the MS currently operates in the serving BS and the neighbor BS, upon receipt of a scanning request from the MS or if determining that scanning is required for the MS, requests the neighbor BS to reserve radio resources for the first frequency band, in the absence of the available radio resources, receives a response message for the resource reservation request from the neighbor BS, and transmits the scanning response message to the MS, if the response message indicates successful resource reservation. The neighbor BS receives the resource reservation request from the serving BS, determines whether available radio resources exist for the first frequency band, searching for a second MS operating in the first frequency band of the first MS and capable of transitioning to a second frequency band among MSs managed by the neighbor BS, in the absence of the available radio resources, releases radio resources used in the first frequency band for the second BS by transitioning the second MS to the second frequency band, if the second MS is detected; reserves the released radio resources for the MS, and sends the response message indicating successful radio resource reservation to the serving BS.
[0033] According to yet further another aspect of the present invention, in a wireless mobile communication system having at least two different frequency modes, a scanning system includes an MS, a serving BS, and a neighbor BS. The MS receives from the serving BS a mobile neighbor advertisement including information about available radio resources of the neighbor BSs, determines whether to measure CINRs of pilot signals received from the serving BS and the neighbor BS, transmits a new scanning request message to the serving BS, if the MS determines to measure the CINRs of the pilot signals, receives a scanning response message for the scanning request message from the serving BS, the response message including information about a BS which has reserved radio resources for a predetermined one of the at least two frequency modes, and measures the CINRs of the pilot signals from the serving BS and the neighbor BS in the predetermined frequency mode. The serving BS transmits the mobile neighbor advertisement message, determines whether radio resources are available for a first frequency mode in which the MS currently operates in the serving BS and the neighbor BS, upon receipt of a scanning request from the MS or if determining that scanning is required for the MS, requests the neighbor BS to reserve radio resources for the first frequency mode, in the absence of the available radio resources, receives a response message for the resource reservation request from the neighbor BS, and transmits the scanning response message to the MS, if the response message indicates successful resource reservation. The neighbor BS receives the resource reservation request from the serving BS, determines whether available radio resources exist for the first frequency mode, searches for a second MS operating in the first frequency mode of the first MS and capable of transitioning to a second frequency mode among MSs managed by the neighbor BS, in the absence of the available radio resources, releases radio resources used in the first frequency mode for the second BS by transitioning the second MS to the second frequency mode, if the second MS is detected; reserves the released radio resources for the MS, and transmits the response message indicating successful radio resource reservation to the serving BS.
BRIEF DESCRIPTION OF THE DRAWINGS
[0034] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which:
[0035] FIG. 1 is a block diagram configuration of a typical IEEE 802.1 6e communication system;
[0036] FIG. 2 is a flow diagram illustrating a signal flow for an MS-initiated scanning operation in the typical IEEE 802.1 6e communication system;
[0037] FIG. 3 is a flow diagram illustrating a signal flow for a scanning operation for an MS-initiated handover in a BWA communication system according to the present invention;
[0038] FIG. 4 is a flow chart illustrating a signal flow for a scanning operation for a BS-initiated handover in the BWA communication system according to the present invention;
[0039] FIG. 5 is a flowchart illustrating a scanning operation in an MS in the BWA communication system according to the present invention;
[0040] FIG. 6 is a flowchart illustrating a scanning operation in a serving BS in the BWA communication system according to the present invention; and
[0041] FIG. 7 is a flowchart illustrating a scanning operation in a neighbor BS in the BWA communication system according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0042] Preferred embodiments of the present invention will be described herein below with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.
[0043] The present invention provides a system and method for enabling an MS to efficiently scan in a BWA communication system using at least two different frequency bands and at least two different frequency modes. The MS performs a successful handover with a minimized handover time delay through the efficient scanning. Furthermore, radio resource utilization is maximized across the entire system.
[0044] In accordance with the present invention, the MS scans in a predetermined frequency band and/or a predetermined frequency mode rather than scanning in all frequency bands and/or all frequency modes. A BS secures radio resources for use in the MS beforehand so as to ensure the success of the handover and minimize the handover time delay for the MS. A WB and an NB are taken as the different frequency bands and FDD mode and TDD mode are taken as the different frequency modes, by way of example. Also, the present invention will be described in the context of a BWA communication system as one of wireless mobile communication systems.
[0045] FIG. 3 is a flow diagram illustrating a signal flow for a scanning operation for an MS-initiated handover in a BWA communication system according to the present invention.
[0046] Referring to FIG. 3 , BSs 330 , 350 and 370 (BS # 1 , BS # 2 , and BS # 3 respectively) operate in at least two different frequency bands and/or at least two frequency modes. For example, they may use an NB and a WB, and FDD mode and TDD mode. Accordingly, an MS 300 must be able to use the NB and the WB, and/or operate in the FDD mode and/or the TDD mode.
[0047] BS # 1 , which is a serving BS for the MS 300 , transmits (i.e., sends) a MOB_NBR-ADV message to the MS 300 periodically in step 302 . To configure the MOB_NBR-ADV message, a partial modification is made to the conventional MOB_NBR-ADV message, specifically to Available Radio Resource. Table 1 illustrates a comparison between the Available Radio Resource fields of the MOB_NBR-ADV message of the present invention and the conventional MOB_NBR-ADV message.
TABLE 1 Code Conventional (%) Present invention (%) 0b0000 0 TDD (or WB) 0 0b0001 20 TDD (or WB) 20 0b0010 40 TDD (or WB) 40 0b0011 60 TDD (or WB) 60 0b0100 80 TDD (or WB) 80 0b0101 100 TDD (or WB) 100 0b0110 Reserved FDD (or NB) 0 0b0111 Reserved FDD (or NB) 20 0b1000 Reserved FDD (or NB) 40 0b1001 Reserved FDD (or NB) 60 0b1010 Reserved FDD (or NB) 80 0b1011 Reserved FDD (or NB) 100 0b1100-0b1110 Reserved Reserved 0b1111 No info No info
[0048] Available Radio Resource is activated when the fourth bit of Skip-Optional-Fields bitmap, associated with QoS related fields is set to 0 in MOB_NBR-ADV. Hence, the serving BS 330 periodically sends the MOB_NBR-ADV message with the fourth bit of Skip-Optional-Fields bitmap set to 0 always to the MS 300 . Thus the MS 300 can determine the average number of subchannels per frame and the average amount of symbol resources per frame for TDD and FDD, and the NB and WB.
[0049] After receiving the MOB_NBR-ADV message, if the signal strength of the serving BS 330 is lower than a predetermined threshold, the MS 300 decides on scanning for a handover in step 304 . Thus, the MS 300 sends a MOB_SCN-REQ message to the serving BS 330 in step 306 .
[0050] Upon receipt of the MOB_SCN-REQ message, the serving BS 330 sends a new RESOURCE-RESERVE-REQ message defined by the present invention to neighbor BSs, i.e., BS # 2 and BS # 3 in steps 308 and 310 . Steps 308 and 310 may be skipped if available radio resources exist for the current operation mode (frequency band) of the MS 300 in the serving BS 330 or a neighbor BS.
[0051] If BS # 2 and BS # 3 have radio resources available for a particular frequency band (frequency mode) requested by the MS 300 , they send RESOURCE-RESERVE-RSP messages to the serving BS 330 , indicating that they have reserved the resources in steps 314 and 316 . In the absence of the resources for the requested frequency band (frequency mode), BS # 2 and BS # 3 transition MSs using the frequency band (frequency mode) under their management to another frequency band (frequency mode), if the MSs can be transitioned. BS # 2 and BS # 3 reserve radio resources saved from these MSs for allocation to the MS 300 in step 312 and notify the serving BS 330 of the radio resource reservation in steps 314 and 316 .
[0052] The serving BS 330 then sends a MOB_SCN-RSP message to the MS 300 in step 318 .
[0053] The MS 300 scans the serving BS 330 and the neighbor BSs 350 and 370 in the frequency band (frequency mode) based on information set in the MOB_SCN-RSP message in step 320 . In step 322 , the MS 300 reports the scanning results to the serving BS 330 by a MOB_SCN-REP message.
[0054] FIG. 4 is a flow diagram illustrating a signal flow for a scanning operation for a BS-initiated handover in the BWA communication system according to the present invention.
[0055] Referring to FIG. 4 , BSs 430 , 450 and 470 (BS # 1 , BS # 2 , and BS # 3 , respectively) can use both the NB and WB and operate in both the FDD mode and the TDD mode, as in the illustrated case of FIG. 3 . Accordingly, an MS 400 must be able to use the NB and/or the WB, and/or to operate in the FDD mode and/or the TDD mode.
[0056] BS # 1 , which is a serving BS for the MS 400 , sends a MOB_NBR-ADV message to the MS 400 periodically in step 402 . The MOB_NBR-ADV message has the fields listed in Table 1.
[0057] When BS # 1 determines that handover is required for the MS 400 , it decides on scanning for the handover in step 404 . Thus, BS # 1 determines whether the neighbor BSs 450 and 470 have resources available for the current frequency mode (frequency band) of the MS 400 based on preliminarily acquired information in step 406 . If the resources are available, BS # 1 sends a MOB_SCN-RSP message to the MS 400 in step 420 . On the contrary, in the absence of the resources in the neighbor BSs 450 and 470 , BS # 1 determines whether the MS 400 must be kept in the current frequency mode (frequency band) in step 408 . If mode transition (frequency band transition) is possible, BS # 1 determines mode transition for the MS 400 in step 418 and sends a MOB_SCN-RSP message requesting mode transition (frequency band transition) to the MS 400 in step 420 .
[0058] On the other hand, if the MS 400 must be kept in the current frequency mode (frequency band), BS # 1 sends a RESOURCE-RESERVE-REQ message to the neighbor BSs, i.e. BS # 2 and BS # 3 in steps 410 .
[0059] If BS # 2 and BS # 3 each have radio resources available for the MS 400 , or if there is any other MSs which operates in the same frequency mode (frequency band) as that of the MS 400 and which can transition to the other frequency mode (frequency band) under the management of BS # 2 and BS # 3 , they transition the other MSs to the other frequency mode (frequency band) and reserve radio resources saved from the other MSs for allocation to the MS 400 in step 412 and notify BS # 1 of the radio resource reservation in steps 414 and 416 .
[0060] BS # 1 then sends a MOB_SCN-RSP message to the MS 400 in step 420 . Upon receipt of the MOB_SCN-RSP message, the MS 400 scans BS # 1 , BS #2, and BS # 3 in the frequency mode (frequency band) in step 422 and reports the scanning results to BS # 1 by a MOB_SCN-REP message in step 424 . In this way, the MS 400 can hand over to one of the neighbor BSs 450 and 470 which has reserved the resources for the MS 400 .
[0061] FIG. 5 is a flowchart illustrating a scanning operation in the MS in the BWA communication system according to the present invention.
[0062] Referring to FIG. 5 , the MS receives a MOB_NBR-ADV message broadcast periodically from the serving BS in step 502 . The MOB_NBR-ADV message has the fourth bit of Skip-Optional-Fields bitmap set to 0 and Available Radio Resource configured as illustrated in Table 1. In step 504 , the MS decides on scanning for handover, if the signal strength of the serving BS is equal to or less than a predetermined threshold. The MS sends a MOB_SCN-REQ message for the handover to the serving BS in step 506 .
[0063] Upon receipt of a MOB_SCN-RSP message from the serving BS in step 508 , the MS scans the neighbor BSs in the current frequency band (frequency mode) irrespective of whether frequency mode transition (frequency band transition) has been performed for the MS in step 510 . The neighbor BSs to be scanned are indicated by the last received MOB_NBR-ADV message. In step 512 , the MS sends a MOB_SCN-REP message containing the scanning results to the serving BS.
[0064] FIG. 6 is a flowchart illustrating a scanning operation in the serving BS in the BWA communication system according to the present invention.
[0065] Referring to FIG. 6 , the serving BS decides on scanning for handover of the MS for the reason of load distribution, for example, in step 602 and determines whether radio resources are available for the current frequency mode (frequency band) of the MS in any neighbor BS in step 604 . In the presence of the radio resources in the neighbor BS, the serving BS sends a MOB_SCN-RSP message to the MS in step 614 .
[0066] In the absence of the radio resources in the neighbor BS, the serving BS determines whether the MS must be kept in the current frequency mode (frequency band) in step 606 . If frequency mode (frequency band) transition is possible for the MS, the serving BS decides on the frequency mode transition (frequency band) transition for the MS in step 612 and sends a MOB_SCN-RSP message requesting scanning in a transitioned frequency mode (frequency band) to the MS in step 614 .
[0067] However, if the MS can operate in the current frequency mode (frequency band) only, the serving BS requests the neighbor BS to save resources from an MS that can transition to the other frequency mode (frequency band) under its management and reserve the saved resources for the handover MS by a RESOURCE-RESERVE-REQ message in step 608 . That is, the neighbor BS performs frequency mode transition (frequency band transition) for an MS which can transition from the frequency mode (frequency band) of the handover MS to the other frequency mode (frequency band) among MSs operating in the same frequency mode (frequency band) as that of the handover MS under management of the neighbor BS, and reserves resources saved from the MS for the handover MS.
[0068] In step 610 , the serving BS receives a RESOURCE-RESERVE-RSP message from the neighbor BS. If the RESOURCE-RESERVE-RSP message indicates failed resource reservation due to the absence of any MS that can transition to the other frequency mode (frequency band), the serving BS can send a RESOURCE-RESERVE-REQ message to neighbor BSs other than the neighbor BS. If all neighbor BSs fail to reserve radio resources for the handover MS, the serving BS drops the call for the handover MS or requests a general scanning other than the handover scanning to the handover MS.
[0069] FIG. 7 is a flowchart illustrating a scanning operation in the neighbor BS in the BWA communication system according to the present invention.
[0070] Referring to FIG. 7 , the neighbor BS receives a RESOURCE-RESERVE-REQUEST message from the serving BS in step 702 and determines the presence (or absence of) radio resources available for the handover MS in step 704 . In the presence of the radio resources, the neighbor BS proceeds to step 710 and in the absence of the radio resources, the neighbor BS proceeds to step 706 .
[0071] In step 706 , the neighbor BS determines whether there is any MS for which frequency mode transition (frequency band transition) is possible. In the presence of an MS that can mode-transition (frequency band transition), the neighbor BS goes to step 708 and in the absence of any MS to be mode-transitioned (frequency band-transitioned), the neighbor BS goes to step 712 . The neighbor BS performs frequency mode transition (frequency band transition) for the MS in step 708 , reserves radio resources saved from the mode (band)-transitions MS for the handover MS in step 710 , and proceeds to step 714 . Meanwhile, the neighbor BS determines that radio resources cannot be reserved for the handover MS due to the absence of any MS for which mode transition (frequency band transition) is possible in step 712 , and goes to step 714 .
[0072] In step 714 , the neighbor BS sends to the serving BS a RESOURCE-RESERVE-RSP message indicating successful resource reservation or failed resource reservation for the handover MS.
[0073] In accordance with the present invention as described above, in a communication system where a BS operates in at least two frequency bands having different central frequencies and/or at least two different frequency modes, an MS scans only in one frequency band and/or frequency mode, thereby preventing a data reception delay and data reception errors involved in the scanning. In addition, since a neighbor BS reserves radio resources beforehand for the frequency band (frequency mode) of the MS, handover is implemented successfully.
[0074] While the invention has been shown and described with reference to certain 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 spirit and scope of the invention as defined by the appended claims. | A system and method for performing handover in a wireless mobile communication system are provided. In a Mobile Station (MS)-initiated scanning method of an (MS) in a wireless mobile communication system having at least two frequency bands with different central frequencies, the MS receives from a serving Base Station (BS) a mobile neighbor advertisement message including information about available radio resources of the neighbor BSs, transmits a new scanning request message to the serving BS, if the MS determines to measure Carrier-to-Interference and Noise Ratios (CINRs) of pilot signals from the serving BS and the neighbor BS, receives from the serving BS a response message for the scanning request message, including information about a BS which has reserved radio resources for a predetermined one of the at least two frequency bands, and measures the CINRs of the pilot signals in the predetermined frequency band. | 7 |
RELATED APPLICATION DATA
This application is a continuation of application Ser. No. 10/954,632, filed Sep. 29, 2004, which claims priority benefit to the following two provisional applications: 60/507,568, filed Sep. 30, 2003, and 60/514,958, filed Oct. 27, 2003. Each of these patent documents is herein incorporated by reference.
FIELD OF THE INVENTION
The present invention relates to printer recalibration, and more particularly relates to methods and apparatuses for such recalibration that do not rely on calorimetric measuring equipment.
BACKGROUND AND SUMMARY OF THE INVENTION
Printers typically employ stored calibration data that maps input image signals into the device's output color space, e.g., to reduce non-linearities in the device's color response. This calibration profile is usually set at the factory, and not thereafter altered.
For many applications, such arrangements are satisfactory. However, in more demanding print environments—such as high end graphic arts work—a printer may be recalibrated periodically. Such recalibration can correct for changes in printer operation due to factors such as changes in ambient temperature, non-uniformities of consumables (e.g., inks), and differences in printing substrates.
U.S. Pat. No. 6,075,888 describes one technique for recalibrating the stored color profile of a printer. Data corresponding to a series of input test colors are provided to the printer, and are mapped to the device's output color space using the stored color profile data. Resulting color patches are printed. Colorimetric values of these patches are then measured, and the results are compared with the input test colors. Differences identified in this comparison are used to adjust the printer's stored color profile, so as to bring the calorimetric measurements of the printed output and the input test colors into better agreement.
While such a recalibration procedure may be practical in some settings, it is impractical in others. Among its disadvantages, the foregoing technique requires expensive colorimetric measuring equipment, and considerable technical expertise. Moreover, it is a prolonged procedure, ill-suited for environments in which regular recalibration may be desirable.
One setting in which the above-detailed procedure is unsuitable is in connection with printers used to produce digitally watermarked photo ID cards, such as driver's licenses. For optimal results, it is desirable to recalibrate such printers periodically (e.g., when the printer ribbon is changed), so that the print quality of the resulting ID card is uniformly excellent, and the watermark information is well concealed yet reliably readable. However, the operator of such a photo ID printing system is typically a person who is relatively unskilled in printer technology and colorimetry, and who lacks the time or equipment to engage in a prolonged procedure.
Accordingly, there is a need for a printer re-calibration procedure that can be performed quickly, without expensive equipment, and without a high level of operator expertise.
In accordance with one embodiment, an operator performs field recalibration of a printer by printing a test graphic on a sample of the target substrate, viewing the printed graphic to discern the visibility of one or more contrasting features, and indicating (e.g., using a computer user interface) whether or not such features are visible. Based on the operator's reports of visibility, it can be determined whether the correct stored calibration data has been used, and whether it has been tweaked correctly. If not, appropriate adjustments can be made.
In some embodiments, the operator prints and assesses three test graphics, respectively evidencing the printer's ability to accurately reproduce image highlights, mid-tones, and shadows. The operator's feedback is used to adjust the stored calibration data so as to better linearize the printer's response across the three ranges.
In other embodiments, the observations can be made by a sensor disposed within the printer housing.
In accordance with a more general embodiment, a printer is instructed to print a test graphic comprised of elements that differ slightly in tone value. By reference to a difference (or absence thereof) between two or more of the elements as actually printed, a corresponding change can be made to the stored printer calibration data.
In one embodiment, the difference is the presence or absence of visible contrast between two features in the printed test graphic. In another embodiment, there are two visible contrast changes in the test graphic, and the distance therebetween is used in determining a change to the stored printer data.
Another aspect of the invention is a printing system with stored profile data, and an internal sensor system by which the foregoing difference(s) in actual printed output can be assessed. Still another embodiment is a printing system that includes a user interface through which operator assessments of printer performance can be received and used in adjusting the stored profile data.
One particular embodiment employs a two-step calibration procedure:
(a) normalize the printer and bring it back to a known condition; and
(b) apply dynamic range adjustment, and check if correct table is applied.
In this embodiment, the software imaging application used with the printer, or the printer driver, is caused to print a gray balance test target that includes several differently-composed (e.g., by different R, G, B values) grey patches. An operator (or a built-in electronic color sensor) makes a visual comparison to identify the patch that most closely matches the color gray on a reference guide shipped with the printer. The selected patch is identified to a software program. This program causes the printer to return to a known condition, tweaking the dynamic range adjustment table and thereafter producing correctly color calibrated images. To confirm correct calibration, a further test pattern can be printed and again visually inspected.
The foregoing and other features and advantages of the present invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of part of a printer, showing the use of a lookup table to map input signal values into output signals that drive the print hardware, to effect desired printer calibration.
FIG. 2 is a plot showing a transfer function of an ideal printer, where each increase in input signal value results in a corresponding increase in printed output tone.
FIG. 3 is a plot showing a transfer function of a printer that is out of calibration.
FIG. 4 shows a facial portrait produced by a properly calibrated printer, such as that whose transfer function is depicted by FIG. 2 .
FIG. 5 shows a facial portrait produced by a mis-calibrated printer, such as that whose transfer function is depicted by FIG. 3 .
FIG. 6 is a plot like FIG. 3 , but showing different features.
FIG. 7 is a plot showing a transfer function of an ideal printer that outputs uniform print tones over a range of input signal values.
FIG. 8 is a plot like that of FIG. 7 , but showing a printer exhibiting a non-linearity like that depicted in FIGS. 3 and 6 .
FIG. 9 shows a test card printed on a properly calibrated printer, like that shown in FIG. 7 .
FIG. 10 shows a test card printed on a printer having a transfer characteristic like that shown in FIG. 8 .
FIG. 11 shows a different test card printed on a properly calibrated printer, like that shown in FIG. 7 .
FIG. 12 shows a test card like that of FIG. 11 , but printed on a printer having a transfer characteristic like that shown in FIG. 8 .
FIG. 13 is a block diagram of a printer according to one embodiment of the present invention.
FIGS. 14-17 show how different printer transfer response curves can be inferred from different printed test card patterns.
FIG. 18 shows how adjustments in the calibration table vary with input signal value.
FIG. 19 shows the transfer function of a different printer that can neither print full black nor full white.
FIG. 20 shows how the transfer function of FIG. 19 may be corrected to yield improved performance.
FIGS. 21 and 22 show still other cards according to aspects of the present invention, which can be used for printer calibration.
DETAILED DESCRIPTION
For expository convenience, the following description focuses on an exemplary application of the technology, namely calibrating a dye sublimation printer of the sort commonly used to produce photo ID documents, such as driver's licenses. Dye sublimation printers are well suited for this application due to the high quality of the printed images, and the stability of the printed substrates.
Dye sublimation—and its close relative, dye diffusion—are thermal imaging technologies that allow for the production of photographic quality images. Dye sublimation typically employs a set of panels (or ribbons) that are coated with a dye (e.g., cyan, magenta, yellow, black, clear-but-UV-responsive, etc.) that can be transferred to a receiver sheet or ID document by the application of heat (and sometimes pressure) from a stylus or thermal printhead at discrete points. The dye sublimates and migrates into the document substrate, where it is chemically bound to the substrate or, if provided, to a receptor coating. Typically, printing with successive color panels across the document creates an image in or on the document's surface.
An image can also be imparted via a so-called “mass transfer” (or thermal mass transfer) panel. Standard dye diffusion printers, such as the model TCP manufactured by Atlantek Inc., and the model Eltron P720 manufactured by Zebra Technologies, often incorporate both dye diffusion and mass transfer panels. A mass transfer panel typically includes a resin (e.g., black resin, or a resin having UV properties) that can be thermally transferred to the ID document.
Further details on such printers are provided in U.S. Pat. Nos. 5,793,403 and 6,532,032.
To simplify the following discussion, a black and white example is particularly considered. However, the same principles can likewise be employed in color embodiments, e.g., by performing such procedures for each of the component color channels.
Referring to FIG. 1 , when image data is provided to a printer 10 , the input pixel values (or other driving signals) are commonly applied to a lookup table 12 that maps the input values to output values needed to cause the print hardware 14 to output the desired shade (color). Thus, for example, if a middle gray of value “128” is desired, the idiosyncrasies of a particular printer design may require a driving signal of value “126” be applied in order to achieve the desired middle gray output. The lookup table 12 serves to map the input value of 128 into an output value of 126.
FIG. 2 shows the result when the lookup table of FIG. 1 is serving its intended purpose. This chart shows the output printed tone (along the vertical axis) as a function of the input data values applied to the printer. As indicated by the straight line, the response is linear. And the response is such that a driving value of 0 yields black, a driving value of 128 yields a middle gray, and a driving value of 255 yields white.
(The shaded blocks along both axes serve simply to identify gross ranges of the data values, i.e., shadows, mid-tones, and highlights. In actual practice, the input data values are not grouped into three sets; nor are the output tones.)
The values in the lookup table 12 are set at the factory and, usually, not thereafter changed. However, factors such as different consumables (inks, print substrates), environmental variables, etc., can cause a printer's response to deviate from the response shown in FIG. 2 .
FIG. 3 shows an illustrative response of a printer that, for some reason, is out of calibration. As can be seen, the response curve is not linear, but instead is bowed. An input value of 0 still results in printed black, and an input value of 255 still results in printed white. However, an input value of 128 no longer results in middle gray. Instead, as shown by dotted line “A,” an input value of 128 results in a lighter tone (up in the “highlights” range).
The results of this mis-calibration are various. In one respect, it has the effect of expanding the shadows in the output image. As shown by range “B” at the bottom of FIG. 3 , the input data values that result in printed tones spanning the “shadow” range are concentrated down at the lowest values of input data. Slightly higher input data values that normally would produce shadow printed tones are now expanded in rendering, producing printed mid-tones.
Likewise, this mis-calibration has the effect of compressing the highlights in the output image. As shown by range “C” in FIG. 3 , some of the input data values that normally would produce printed mid-tones are here rendered as highlights instead. The input data values that normally would span the full range of highlights now result in output tones compressed at the top end of the highlight range.
FIGS. 4 and 5 show the result of this mis-calibration. FIG. 4 shows a facial photo as rendered on a properly calibrated printer. FIG. 5 shows the same photo as rendered on a printer having the response curve shown in FIG. 3 .
As can be seen, the mis-calibrated FIG. 5 photo still has full-black and full-white portions. However, many of the mid-tones are transformed into highlights; and the intended highlights are largely washed out.
In addition to inferior aesthetics, the mis-calibrated FIG. 5 photo also suffers significantly as a carrier of steganographic (e.g., digital watermark) information. For best reliability of watermark communications, the tonal variations intended by the input image data should be faithfully reproduced in the output print.
Referring again to FIG. 3 , it can be seen that a wide range of input signal values (e.g., 128-255) are rendered in a narrow range of output print tones (e.g., mid-highlights and above). This is important in watermarking because the watermark signal itself is typically of low amplitude. That is, a watermarked pixel may vary by just a few digital values from the same pixel prior to watermark encoding. If a small variation in input signal values is rendered as a further-reduced variation in output tone values, then the variation may become too small to detect, and reliability of communication suffers.
Related, in the shadow tones, a small change in input signal value is rendered as an exaggerated change in output tone. This can have the undesirable effect of magnifying the small signal introduced by the watermarking process, rendering it more visible in the printed output.
Thus, at one end of the visible range, the watermark signal may be too weak to serve its intended purpose, and at the other end of the visible range the watermark signal may be so strong as to become visibly objectionable.
The problem is conceptualized in a slightly different way in FIG. 6 . In this figure, the dashed line indicates the desired, linear, response between input signal values and output print tones. This line has a constant slope of 45°, indicating that every increment in input signal yields the same increment in output tone darkness. The solid line of FIG. 6 , in contrast, indicates the actual, mis-calibrated printer transfer function.
As can be seen, the slope of the solid line varies over its range. For input signal values corresponding to most shadow output tones, the slope theta A of a line tangent to the transfer function curve is greater than 45°. For an input signal value somewhere between light shadows and darker mid-tones, the slope theta B is 45°. From the middle mid-tones and above, the slope theta C is less than 45°.
The slope of the curve may be regarded as contrast—the change in printed tone for a given change in input data value. At small input data values (corresponding to intended shadows), the slope is high, and the change in output tone is relatively great for a given change in input data. At middle and larger input data values (corresponding to upper mid-tones and highlights), the slope is low, and the change in output tone is relatively small for a given change in input data.
Again, watermark encoding is usually premised on a straight-line contrast function across all values of input data.
(If the transfer function distortion were known in advance, and known to be unchanging, the watermark encoding could be tailored to conform to this distortion, e.g., by reducing watermark signal added to small input signal values, and increasing the watermark signal added to large input signal values. However, such a known, unchanging transfer function is generally not the case.)
FIG. 7 shows another complication. Many printers cannot print 256 discrete output tones. Dye sublimation printers of the sort used in printing drivers licenses, for example, can print only about 32 discrete tones. Further gradation is not generally practical due to the physics of the printing mode. (Inkjets are even worse—typically only being able to produce 4 discrete output tones, due to limited control of droplet volume.)
Most inkjet printers, and some other printers, use dithering techniques to redress this shortcoming, e.g., by alternating between two discrete output tones to simulate intermediate tones. Other printers, including many dye sublimation printers, do not.
Thus, a dye sublimation printer has a stepped transfer function, as shown in FIG. 7 . For input signal values of 0-7, the printer responds with a full-black output tone. For input signal values of 8-15, the printer responds with its next-to-black output tone. In like fashion, there are eight different input signal values for each stepped printed output tone. The input signal must cross one of these occasional threshold values before the output printed tone changes.
Printed output from such a printer thus bands close input signal values together into a uniformly-toned output, as shown by FIG. 9 .
FIG. 9 is a test card printed with two stripes. The upper stripe is printed by uniformly varying the input signal value from 64 to 95. Instead of 32 printed output tones, the stripe consists of just 4 banded tones: one output for input signal values of 64-71; another for input signal values of 72-79; another for 80-87; and the last for 88-95.
The lower strip in FIG. 9 is printed by uniformly varying the input signal value from 224 to 255. Again, the same effect is manifested.
(It will be recognized that the tones actually printed in FIG. 9 are not accurate, but are selected from a limited palette of shading patterns available in the drafting tool used. The printed tones for the upper stripe should be much darker (shadows) than the tones for the lower stripe (highlights). And the printed tone for the range 248-255 is white; the dashed border around the area in the lower right of FIG. 9 would not actually appear.)
The transfer function of FIG. 7 (and the card of FIG. 9 ) correspond to the ideal case, in which the printer's transfer function between input driving signal, and output printed tone is linear (albeit stepped). The transfer function of FIG. 8 shows the case in which the non-linearity earlier discussed is present.
In FIG. 8 , the dashed curve is the transfer function of FIGS. 3 and 6 . The solid line is the stepped transfer function of the actual printer. Unlike the ideal case of FIG. 7 , the number of input signal values for each discrete output printed tone is not constant. At low signal values, the number of input signal values per step is small, e.g., 2-4. At large signal values, the number of input signal values per step is large, e.g., 8-14.
Thus, in the printer whose transfer function is illustrated, input values of 0 and 1 result in an output printed tone of full black (as opposed to input signal values of 0-7 in FIG. 7 ); input values of 2 and 3 result in an output printed tone of next-to-full black (as opposed to input signal values of 8-15 in FIG. 7 ). At the other end of the spectrum, input signal values of 242-255 may result in an output printed tone of full white (as opposed to input signal values of 248-255 in FIG. 7 ).
FIG. 10 shows the same test pattern as printed on the card of FIG. 9 , but using a printer having the FIG. 8 transfer function. As can be seen, the upper stripe of FIG. 10 here spans five discrete output tones, instead of the four of FIG. 9 . That is, instead of eight adjoining input signal values producing the same printed output tone, about six adjoining input signal values produce the same printed output tone. The widths of the printed bands are correspondingly reduced.
The lower stripe in FIG. 10 shows the complementary effect for high input signal values. The lower stripe spans three discrete output tones, instead of the four of FIG. 9 . Instead of eight adjoining input signal values producing the same printed output tone, about 12-14 adjoining input signal values produce the same output tone. The widths of the printed bands are correspondingly increased.
(It will be recognized that the edges of the upper stripe in FIG. 10 , and the left edge of the lower stripe, may not be at tonal transition points. That is, the same printed tone may continue for input signal values beyond the range printed in these stripes, i.e. “off-the-card.”)
According to one aspect of the invention, information about the distortion of a printer's transfer function can be inferred by the width of one or more printed bands on a card like that of FIG. 10 .
The width assessment can be absolute or relative. In an absolute example, the width of a band in FIG. 10 can be measured (e.g., by a ruler). The middle band in the upper stripe, for example, may be measured to have a width of about 16 mm. The middle band in the lower stripe may be measured to have a width of about 24 mm. (In a correctly calibrated printer, i.e., which produced the card of FIG. 9 , all bands may have a width of 20 mm.)
In a relative width assessment, a check can be made whether the bands in the top stripe are wider, or narrower, than the bands in the lower stripe.
These assessments (which can be made manually by an operator, or by an automated arrangement), can be used to infer the shape of the transfer function curve.
One exemplary automated arrangement is shown in FIG. 13 , and includes an illumination source and a photosensor to detect changes in contrast in printed cards (e.g., the contrast change between adjoining bands on the test cards of FIGS. 9 and 10 ). A stepper motor moves the card past the print station in controlled steps. This position data is known to the CPU, which uses the known positions at sensed contrast changes to determine the width of each printed bands. FIG. 13 also shows a user interface by which operator assessments of the printed test card(s) can be entered. (It will be recognized that an arrangement like that depicted in FIG. 13 can be included in any prior art printer—equipping it to practice methods according to the present invention.)
Referring to FIG. 14 , if the bands in the top stripe are narrower than expected, and the bands in the lower stripe are broader than expected, then the transfer function can be inferred to have the general shape shown on the right side of that figure.
Referring to FIG. 15 , if the bands in the both stripes have equal widths, then the transfer function can be inferred to be linear, as shown on the right side of that figure.
Referring to FIG. 16 , if the bands in the top stripe are broader than those in the lower strip, then the transfer function can be inferred to have the general shape shown on the right side of that figure.
Generally speaking, narrow bands indicate too much contrast, i.e., too much slope in the corresponding part of the transfer function curve (and a corresponding excess in the angle theta). Conversely, broad bands indicate too little contrast, i.e., too little slope in the corresponding part of the transfer function (and a corresponding shortage in the angle theta).
Usually, too-narrow bands at one end of the input signal range are accompanied by excessively broad bands at the other end of the range. However, this need not always be the case. FIG. 17 shows an example, in which the bands are too broad at both ends of the spectrum. In this case, the transfer function in the middle range of input signal values is steep, with a large angle θ.
It will be recognized that the test cards shown in FIGS. 14-17 are somewhat incomplete, in that they don't provide printed output except in the range of input signal values 64-94 and 224-255. However, in other embodiments, broader ranges of input signal values can be tested, e.g., by using more printed test stripes. Or one or more stripes can be printed spanning a larger range of input signal values (e.g., in the limiting case, spanning 0-255). Multiple cards may be used, or all the stripes can be printed on a single card.
One alternative test card includes three stripes—one centered around the mid-point of the shadow range (e.g., centered around an input signal value of about 42), one centered around the mid-point of the mid-tone range (e.g., centered at about 128), and one centered around the mid-point of the highlights range (e.g., centered at about 214). Each range could extend to meet the adjoining range (e.g., each spanning about 85 digital numbers). Or the range could be shorter or longer.
Desirably, the range is not so short that an edge of a band of interest (i.e., the border at which the contrast changes with steps in the output tone) is “off-the-card.” For example, if broad bands—each corresponding to up to 14 different input signal values—are anticipated, then a range of 25 input signal values may be too small. One band may be partially off the left edge of the card, and have 12 values “on the card.” The adjoining band may start with 13 values “on the card” and terminate with another value off the right edge of the card. Neither band is measurable, since each ends off the card.
In preferred embodiments, each stripe spans a number of input signal values at least equal to 2N+1, where N is the broadest band anticipated (measured in range of corresponding input signal values).
Once the shape of the transfer function has been inferred (which may be by the foregoing procedure, or otherwise), then the calibration data stored in the printer can be changed accordingly.
In one embodiment, the printer has an interface through which data characterizing the shape of the transfer function is received. If the assessments are made by a human operator, this interface can be a graphical user interface, such as a display on a screen with which the user interacts by means such as typing, touching, or mouse clicking, etc. If the assessments are made by one or more sensors within the printer, the interface can be an electrical or data interface.
The adjustments to the stored calibration data can be effected in various ways. One is by adding (or subtracting) small values (e.g., 1 to 10) to the calibration data already stored (e.g., in lookup table 12 of FIG. 1 ). Another is by multiplying the existing calibration data values by corresponding scale values (i.e., values close to 1, such as 0.85 to 1.15). Still another is by maintaining the original calibration data, and effecting the changes in another lookup table that is serially interposed before or after the table in which the original calibration data is stored. The input data can thus be pre-compensated before application to the table 12 of FIG. 1 , or the output data from table 12 can be post-compensated through such a table. (In all these cases, iterative adjustment and re-testing can be employed.)
The adjustments can be tailored to precisely correspond to the assessed print characteristics, or rote adjustments can be employed.
In the latter case, the shape of the actual transfer function may be first identified as either of the form shown in FIG. 14 (i.e., the bands in the upper stripe are narrower than those in the lower stripe), or of the form shown in FIG. 16 (i.e., the bands in the upper stripe are broader than those in the lower strip). If the test card indicates a situation like that shown in FIG. 14 , the lookup table values should generally be decreased—with the largest decrease at the middle of the range, tapering to nil change at either end. This is shown in the following tables, with the original values in parentheses and replaced with adjusted values:
TABLE I Input Value Output Value 32 (32) 30 64 (64) 61 96 (96) 92 128 (128) 123 160 (160) 156 192 (192) 189 224 (224) 222
Conversely, if the actual curve is found to be of the general shape shown in FIG. 16 (i.e., the bands in the upper stripe are broader than the bands in the lower stripe), the lookup table values should generally be increased—with the largest increase at the middle of the range, tapering to nil change at either end. This is shown in the following pair of lookup tables, with Table III being the lookup table prior to adjustment, and Table IV being the table after adjustment.
TABLE II
Input Value
Output Value
32
(32) 34
64
(64) 67
96
(96) 100
128
(128) 133
160
(160) 164
192
(192) 195
224
(224) 226
These changes may more readily be understood by reference to FIG. 18 (which corresponds to the FIG. 14 form of distortion). It will be noted that the largest discrepancy between the idealized straight-line transfer function and the actual transfer function is in the range of middle input signal values, with the difference tapering to zero at the ends. If the desired output tone is indicated by the arrow A, this output would ideally be produced by an input signal value B. However, due to the non-linearity of the printer, it is actually an input signal value C that produces this desired output tone A. To linearize the curve, the lookup table output value formerly found for input value C should be substituted at input value B, i.e., a reduction in the amount shown by the arrow D.
The rote adjustment noted above, based on inferred transfer function curve shape, can be applied and another test card then run using the adjusted printer. If the second test card still has the appearance of FIG. 14 (i.e., with the upper bands being narrower than the lower bands) then the same adjustment can be applied again. This procedure can be repeated until the band widths in the upper and lower test stripes are approximately equal.
In another arrangement, a compensation particularly tailored to the observed test results can be applied. For example, referring to FIG. 14 , it will be recognized that the absolute width of the band for an input signal value of 72 is related to the slope of the printer's transfer function at this value. By measuring the widths of the bands around different input signal values, a relatively precise inference of the required adjustments to the lookup table data can be made. (To accurately adjust the lookup table, it is best to print test strips encompassing the full range of input signal values so that the printer operation is characterized over its full range of operation.)
If the printer interface is provided with data indicating the measured width of each of the bands for input signal values ranging from 0 to 255, the lookup table data can be precisely corrected. Thus, if the first band (i.e., input signal values of 0-7) has a width of 10 mm., and is expected to ideally have a width of 20 mm., then it can be seen that the slope of the transfer function is twice the correct value (i.e., the width of the band is directly related to slope of the transfer function). To compensate for this, adjustments per the following table may be applied (again, these adjustments can be made by subtracting from the values earlier in the table, or by multiplying the original table values by scaling factors, or by pre- or post-compensation tables, etc.):
TABLE III
Input Value
Output Value
0
0
1
(1) 0
2
(2) 1
3
(3) 2
4
(4) 2
5
(5) 3
6
(6) 3
7
(7) 4
. . .
. . .
The same assessment, and correction, can be performed for each successive band of input signal values.
Another type of adjustment is somewhat more than rote, but somewhat less than fully precise. This type of adjustment is based on the number of bands appearing in the top and bottom test stripes. In FIG. 14 , the numbers are 5/3. In FIG. 15 it is 4/4. In FIG. 16 it is 3/5. In FIG. 17 it is 3/3. Each of these pairs of numbers can invoke an associated adjustment in the compensation table. The more bands in each stripe, the steeper the actual transfer function curve in the corresponding portion of the input signal range. Conversely, the fewer bands in each stripe, the more gradual the actual transfer function curve. Knowing the relative steepness of the curve in different regions, correspondingly different adjustments can be applied to the printer calibration data.
A different test card is shown in FIGS. 11 and 12 . The FIG. 11 card was printed on a correctly calibrated printer; the FIG. 12 card was printed on a printer whose transfer function is like that shown in FIG. 8 .
In both cards, the background appearing in the top three tiles is printed using an input signal value of 82. The letters A, B and C are printed using input signal values of 80, 78 and 70, respectively. (These particular numbers are somewhat arbitrary, but serve to illustrate some of the operative principles.)
Consider first the tile in the upper left of FIG. 11 . Recall that in a correctly calibrated printer, input values of 80-87 all produce the same printed output tone. (Likewise, input values of 72-79 all produce the same, slightly darker, tone, and input values 64-71 all produce the same, still darker, tone.) Thus, the letter A (printed with input value 80) should not visibly contrast with the surrounding background area (input value 82), since both should fall within the same output tone band. But letter B (printed with input value 78) should be visible, as it should fall in a different output tone band than the background (82). Even more apparent should be letter C, since it is printed with value 70 that is in a different, and not even adjoining, output tone band
Likewise in the lower tiles of FIG. 11 . The background is printed using an input signal value of 242. The letters D, E and F are printed with input signal values of 240, 238 and 230, respectively.
Again, in a properly calibrated printer, the letter D should not be visible. That is, the input signals that form the letter D (value 240) should produce the same output tone as that produced by the input signals corresponding to the surrounding background (value 242). However, the letter E should be visible, as the input signal that produced it (238) should produce a different output tone than the background signal (242). And letter F should be even more visible, since it is printed with a value (230) that yields a tone falling in a different, and not even adjoining, band than the background (242).
Thus, if a test card of the type just detailed is printed on an ideally calibrated printer, then it should have the appearance of FIG. 11 , with the letters A and D not visible, and the other letters in each row having progressively more visibility.
FIG. 12 shows the same card printed on a printer having the transfer function detailed in FIG. 8 . Recall that in this mis-calibrated printer, input signal values corresponding to shadow tones are printed with too much contrast. That is, the output shadow tone bands do not correspond to 8 input signal values each (as in the ideal case), but instead correspond to only 2 to 4 input signal values. So in this case, instead of the letter A input signal (value 80) falling within the same output tone range as the surrounding background (input signal value 82), it falls within a different output tone range. Accordingly, the A contrasts with the background and becomes visible. As before, letters B and C are visible. (In this case, letters B and C are even more apparent than before, since they fall in tone bands further spaced from the background tone, due to the high contrast of the mis-calibrated printer in these shadow tones.)
The mis-calibration yields a different result in the lower 3 tiles of the FIG. 12 test card. Here, as before, the letter D (input signal value 240) produces an output tone identical to the surrounding background (input signal value 242), and is thus not apparent. However, in this case the letter E is also not apparent. This is because the printer's mis-calibration causes its input signal value (238) to be rendered as the same output tone as the surrounding background area (242)—contrary to the printer's ideal operation. Letter F is visible in FIG. 12 , but only barely. While the printer has rendered its input signal value (230) in a different output tone than the surrounding background (242), it is not as visibly distinct as in the FIG. 11 test card, because the letter and the background are rendered in adjoining output tones.
Thus, by examining a test card like that detailed above, certain mis-calibrations of the printer can be inferred. If the letter A is visible, then this generally means that the printer provides too much contrast in the shadows (i.e., the transfer function curve is too steep in this area). Likewise, if the letter E is not visible, then this generally means that the printer provides too little contrast in the highlights (i.e., the transfer function curve is too gradual in this area).
Moreover, although not particularly illustrated, it will be recognized that if the letter B is not visible, then this generally means that the slope of the transfer function is too gradual for input signal values that are intended to produce shadows (i.e., too little contrast in the lower values of input signals). Conversely, if the letter D is visible, then this generally means that the slope of the transfer function is too steep for input signal values that are intended to produce highlights (i.e., too much contrast in the higher values of input signals).
(The reference to “generally” in the foregoing paragraphs is an acknowledgement that the visibility of a letter on the FIG. 12 test card—or lack thereof—may not be due to too much or too little localized slope in the transfer function. Instead, this effect could be present in a printer with a generally linear response characteristic, e.g., if the transition between pure black and next-to-black occurs between input signal values of 6 and 7, instead of between 7 and 8. A single such misplaced transition boundary could cause some apparently atypical behavior through parts of the input signal range that are highly linear. This is another example of uncertainty that can be addressed—if desired—by a more thorough evaluation of the printer performance, e.g., by using test cards that involve many more input signal values than the few shown in FIG. 12 .)
Again, it will be recognized that test cards of the sort just-discussed can be assessed by a human operator, and the observed results entered into a user interface (e.g., “Type in the letters that are visible on the card”). The printer CPU can respond to these assessments to adjust the lookup table data as earlier described. Alternatively, the sensing of the characters can be done with one or more electronic sensors (as indicated in FIG. 13 ), and this data again used to drive corresponding changes in the lookup table values.
While the foregoing examples depict a printer whose distorted transfer function encompasses the full range from black to white, the same principles can be applied to any printer. Consider a printer whose actual transfer function is shown by FIG. 19 . This printer cannot output a true black (perhaps due to the substrate's resistance to accepting dye) and cannot output a true white (perhaps due to a tinting of the substrate color). Nonetheless, its printing can be improved—especially for watermarking purposes—by linearizing the range of responses that the environmental factors (e.g., substrate characteristics) permit. Thus, the transfer function of FIG. 19 might be corrected to that shown in FIG. 20 . Likewise, it is not a requirement that the printer have a relatively simple transfer function of the sort depicted in FIGS. 13 , 15 and 16 . These were chosen to facilitate explanation. The same principles are applicable to printers having any form of transfer function curve.
FIGS. 21 and 22 show yet other forms of printer calibration cards. These cards can be used by printer operators to re-calibrate printed hues, e.g., whenever printer consumables (e.g., inks, transfer ribbons, or substrates) are changed. (Changing any of these consumables may trigger the printer to present a prompt to the user requesting or requiring recalibration.)
The card 90 of FIG. 21 is comprised of plural rectangular patches 92 . Each is printed with a color tone defined by different R-G-B values. The triplet of numbers (e.g., 42/56/50 in the upper left patch) represents the percentage of red, green, and blue. In the printer earlier detailed (with each color ranging in value from 0 to 255), the 42% corresponds to a green value of 0.42*255, or 107; 56% corresponds to a red value of 143, and 50% corresponds to a blue value of 128.
In actual practice, the triplet of values is not printed on the card; they are shown in FIG. 21 for illustrative purposes only. Instead, each patch 92 is of a uniform color (optionally, with an identification indicia printed therein).
The card of FIG. 21 thus presents a spectrum of 60 colors. The patch near the center, with the bold outline, is intended to be printed in mid-gray, i.e., 50% values of red, green and blue. Those to the left of this patch have decreasing amounts of red (2% less in each successive column, in the illustrated card). Those to the right of this patch have similarly increasing amounts of red. Those below this patch have decreasing amounts of green (3% less in each successive row, in the illustrated card). Those above this patch have similarly increasing amounts of green.
It will be recognized that the color blue is said to be constant at 50% in the patches of the FIG. 21 card. Desirably, however, since the values of colors red and green change, the proportion of blue to these colors should also change. That is, in a more preferred arrangement, blue is relatively more dominant in patches to the upper left, and is relatively less dominant in patches to the lower right.
FIG. 22 shows a companion card 94 comprising a reference patch of true gray 96 (i.e., 50/50/50). Typically, this card is provided by the printer vendor and is not printed by the operator at the time of recalibration. Formed through card 94 is a hole 98 .
In use, companion card 94 is slid by the operator over test card 90 until the color of the patch 92 showing through the hole 98 most closely matches the reference gray color 96 on the companion card. The reference indicia of the patch 92 containing the best-match color is then typed (or otherwise) entered into a user interface.
Imagine that the operator types “10” into the user interface, signaling to the printer that the patch in the upper left of the card has a color most closely matching the reference gray of the companion card 94 . The printer CPU responds by making appropriate changes to lookup table data in the printer (e.g., changes of the sort discussed earlier).
In this case, the R-G-B values associated with patch 92 are 42/56/50. As to the 42% red, the printer actually rendered this patch with about 50% red (since patch 92 is closest to true mid-gray). Accordingly, the printer as originally calibrated was printing red too strongly (i.e., the printer's red transfer function may appear like the curve to the right of FIG. 14 ). To redress this, a lookup table adjustment is made to reduce the amount of red printed at the middle of the transfer function curve. (As before, the maximum adjustment may be made towards the middle of the curve, with tapering amounts of adjustment made towards either end.)
The green value of patch 92 is 56%. The printer as originally calibrated printed this patch with a green component more like 50% (since this patch was found to be closest to true gray). Accordingly, it appears the printer did not apply as much green to the printed output as the driving signals intended (i.e., the green transfer curve may have a shape like that shown at the right side of FIG. 16 ). Again, a corresponding change can be made to appropriate lookup table values, e.g., to increase the amount of green applied at middle values, with tapering changes applied at greater and lesser green values.
As noted, all patches in the FIG. 21 card are desirably arranged to have approximately the same luminance, so when red and green are both increased, blue is decreased to keep the luminance constant. Similarly when red and green are both decreased, blue is increased to keep the luminance constant.
More than one card may need to be printed with different levels of luminance, if the change in consumables causes a luminance shift. If a scanner is being used, several different luminance levels (say 4) could be printed on the same card and the luminance and color shift determined together.
The foregoing procedure improves accuracy of printer response in the middle of the color transfer functions. If desired, similar test cards can be made and used to calibrate color contributions in the shadows (e.g., patches centered about 20%, 20%, 20%, compared against a true dark gray patch with these values) and in the highlights (e.g., patches centered about 80%, 80%, 80%, compared against a true light gray patch with these values).
Recall that the printer earlier detailed does not render 256 tones of any color. Instead, only 32 gradations of each color are possible. In printing the test patches on card 21 , dithering may be used to obtain intermediate color values. Although the printer may not nominally provide dithering capability, dithering techniques can be employed in establishing the pixel values that make up each of the patches 92 .
In an illustrative embodiment, the known Floyd-Steinberg successive error-dispersion dithering technique is used. Thus, if a red value of 242 is desired, and the nearest values the printer can render are 240 and 248, then patch 92 can comprise an array of pixels in which 75% have a red value of 240, and 25% have a red value of 248—interspersed in regular fashion. Thus, the print file provided to the printer comprises just these 240 and 248 values.
The foregoing examples are naturally subject to myriad variations. In the test card of FIG. 21 , for example, it will be recognized that the increments by which the colors change in successive rows/columns can be tailored to particular applications; the 2% and 3% numbers are not critical. Nor is it essential that all patches in a row or column share one or more common value.
Although calibration was described with reference to tests based on red, green and blue, tests using other color spaces can of course be used (CMYK being among the alternatives).
The techniques just described can be used in combination, or in hybrid form, with those earlier described—providing increased calibration accuracy.
It should be recognized that the principles discussed above are applicable in contexts other than those particularly detailed. Thus, it is not essential that the invention be employed with dye sublimation printers; any printer can employ these principles. For example, excellent quality photo ID cards can also be produced by using ink jet printing to print on a substrate sheet, e.g., a Teslin® sheet. The ink jet printed substrate is then preferably over laminated with, e.g., polyester laminates and then cut into a typical ID card size (e.g., conforming to an ISO standard). Other printing technologies, including color xerography, offset press, laser engraving, etc., can likewise benefit by application of the present technology.
Moreover, the example of an input signal that ranges in value from 0 to 255 is exemplary only, not limiting. Similarly, there is nothing essential about the print mode being able to produce only 32 distinct output tones. Although the illustrative printer does not employ dithering or other known image enhancement techniques, embodiments of the invention can use such techniques if desired. (In some such embodiments it may be desirable to temporarily disable dithering when printing certain test patterns, so the transfer response transitions can be more readily discerned.)
Of course, it will be recognized that the techniques detailed herein find application in myriad printing applications, not just in the production of digitally watermarked photo ID cards.
Not much has yet been said about the details of digital watermarking. Such technology is well known in the printing art. The assignee's U.S. Pat. No. 6,614,914 is exemplary. Some of my earlier work in this field is detailed in U.S. Pat. No. 6,700,995 (“Applying Digital Watermarks Using Dot Gain Correction”) and published application US 2002-0164052 (“Enhancing Embedding of Out-Of-Phase Signals”). Other applications that particularly discuss watermark technology as it relates to identification cards (e.g., drivers' licenses) include 60/495,373, filed Aug. 14, 2003 (“Identification Document and Related Methods,” which served as a priority application for published document US 2004-0181671) and US 2003-0183695 (“Multiple Image Security Features for Identification Documents and Methods of Making Same”). The teachings of each of these documents can be employed in embodiments according to the present invention. These patent documents, as well as those earlier cited, are incorporated herein by reference.
Having described and illustrated the principles of my inventive work with reference to illustrative embodiments thereof, it will be recognized that these embodiments are illustrative only and should not be taken as limiting the scope of the invention. Rather, I claim as my invention all such modifications as may fall within the scope and spirit of the following claims, and equivalents thereto. | A test pattern printed by a printer is assessed—without colorimetric equipment—to provide data used in recalibrating the printer. The assessment may be made by an unskilled operator, and can include discerning whether a particular pattern is visible in the printed test pattern, or whether a feature in the test pattern is relatively wider or narrower. From such assessment, needed changes to the printer's calibration data are inferred and implemented. A variety of other printer calibration techniques are disclosed. The technology is illustrated in the context of dye sublimation printers, and is particularly useful in optimizing printing of digitally-watermarked graphics. | 7 |
FIELD
The invention relates to dry type transformers and, more particularly, to a dome area of the transformer that has features to increase the track path between taps.
BACKGROUND
A dry type transformer uses a complex system of air and solid insulation to prevent energized parts from contacting each other or ground. Many dry type cast coil transformers, such as disclosed in U.S. Pat. No. 6,445,269, are filled with epoxy in a horizontal orientation which makes a flat top surface called a ‘dome’. The dome area of a transformer houses the start and finish taps as well as voltage adjustment taps that have a large voltage gradient. This voltage gradient can cause solid insulations to electrically track due to material properties and distance. This dome area is where the customer makes connections to the transformer and where the voltage input/output of the transformer is adjusted to account for the incoming utility voltage. One of the main considerations is the track path from an energized part to another conductive part at a different potential. The flat top surface of the conventional dome area can lead to medium voltage tracking between energized parts when exposed to harsh environments such as off shore platforms, refineries, wind turbines, pulp and paper mills, etc.
Conventionally, increasing the track path requires the transformer coil to be cast with the voltage adjustment taps oriented downwardly or vertically to create bushings. Such a transformer coil has two common disadvantages. First, more epoxy is used than actually needed to fulfill the requirements of the coil. Secondly, the regions of the unnecessary epoxy are prone to the risk of cracks because of the large thickness of epoxy.
Thus, there is a need to provide a dome structure for a dry type cast coil transformer with undulation structure that allows a greater track path between taps, allows a casting process where the voltage taps face upwardly, and uses less epoxy than conventional dome areas.
SUMMARY
An object of the invention is to fulfill the need referred to above. In accordance with the principles of the present invention, this objective is obtained by a dry type cast coil transformer that includes a hollow body, a dome structure extending from the body, and undulation structure, defining at least a portion of an outer surface of the dome structure, constructed and arranged to increase an electrical track path in the dome structure.
In accordance with another aspect of the disclosed embodiment, a method of molding a dry type cast coil transformer having a dome structure is provided. The method provides a mold having a dome mold structure. The dome mold structure includes features for molding at least two tap connection bases from which a respective tap connection extends, and undulation forming structure adjacent to the bases for molding undulation structure. Windings are placed in the mold. The windings are coupled to the tap connections. The mold is oriented so that the tap connections are arranged upwardly. Epoxy is poured into the mold and permitted to cure. The mold is removed to obtain the cast coil transformer having the undulation structure adjacent to the tap connection bases.
Other objects, features and characteristics of the present invention, as well as the methods of operation and the functions of the related elements of the structure, the combination of parts and economics of manufacture will become more apparent upon consideration of the following detailed description and appended claims with reference to the accompanying drawings, all of which form a part of this specification.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be better understood from the following detailed description of the preferred embodiments thereof, taken in conjunction with the accompanying drawings, wherein like reference numerals refer to like parts, in which:
FIG. 1 is a top view of a mold for forming an outer surface of a dome structure of a dry type cast coil transformer, providing in accordance with an embodiment.
FIG. 2 is a view of the underside of the mold of FIG. 1 showing undulation forming structure therein.
FIG. 3 shows the top surface of a dome structure of a dry type case coil transformer having undulation structure resulting from the mold of FIG. 2 .
FIG. 4A shows undulation structure having half-moon shape in accordance with another embodiment.
FIG. 4B shows undulation structure having inverse half-moon shape in accordance with another embodiment.
FIG. 4C shows undulation structure having saw-tooth shape in accordance with yet another embodiment.
FIG. 4D is shows undulation structure having sine wave shape in accordance with another embodiment.
FIG. 4E is shows undulation structure having cosine shape in accordance with still another embodiment.
FIG. 5 is a perspective view of a conventional mold for a dry type cast coil transformer, with the mold having an open top forming the dome structure.
FIG. 6 is a perspective view of mold for a dry type cast coil transformer in accordance with an embodiment, with the mold having additional structure on the top side for forming the dome structure.
FIG. 7A is a schematic end view of a three-sided dome shape in accordance with an embodiment.
FIG. 7B is a schematic end view of a five-sided dome shape in accordance with an embodiment.
FIG. 7C is a schematic end view of a circle dome shape with an offset in accordance with an embodiment.
FIG. 7D is a schematic end view of a three-sided dome shape with rounded edges in accordance with an embodiment.
FIG. 8A is a schematic side view showing two end-tap molds and a spacer for an embodiment of a dry type cast coil transformer.
FIG. 8B is a schematic side view showing two end-tap molds and three spacers for an embodiment of a dry type cast coil transformer.
FIG. 8C is a schematic side view showing two-end tap molds, one center-tap mold and two spacers for an embodiment of a dry type cast coil transformer.
FIG. 8D is a schematic side view showing two-end tap molds, one center tap mold and four spacers for an embodiment of a dry type cast coil transformer.
FIG. 9 is a top perspective view of a dome structure of a dry type cast coil transformer with tap connection bases resulting from the mold of FIG. 6 .
FIG. 10 is a top perspective view of a dome structure of a dry type cast coil transformer with undulation structure adjacent to raised tap connection bases in accordance with and embodiment.
FIG. 11 is a perspective view of a mold for another shape of the dome structure of a dry type cast coil transformer.
FIG. 12 is a perspective view of a dry type cast coil transformer with a dome structure formed by the mold of FIG. 11 .
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
With reference to FIGS. 1 and 2 , a mold portion 10 is shown, for molding a dome structure of a dry type cast coil transformer 28 ( FIG. 3 ), in accordance with and embodiment. The mold portion 10 includes a base 12 , a pair of opposing side walls 14 and a pair of opposing end walls 16 . As shown in FIG. 2 undulation forming structure, generally indicated at 18 , extends from the underside of the base 12 . The undulation forming structure 18 includes a plurality of alternating, continuously joined, peaks 20 and valleys 22 . In the embodiment, the peaks 20 define rounded fins and the valleys 22 are also rounded.
To form a cast coil transformer, a winding (not shown) with suitable is insulating material is placed in a mold (see, e.g., mold 68 ′ of FIG. 6 ) that includes the mold portion 10 . Liquid epoxy is then poured into the mold and cured. With reference to FIG. 3 an outer surface 24 , of a dome structure 26 of a dry type cast coil transformer 28 , is shown that results from using the mold portion 10 of FIG. 2 . The body 29 of the coil transformer 28 is of conventional, hollow, generally cylindrically shaped configuration, with the dome structure extending from the body 29 . The winding is cast inside the body 29 . The outer surface 24 includes undulation structure, generally indicted at 30 , that includes a plurality of alternating, continuously joined, peaks 32 and valleys 34 . As shown in FIG. 3 , each peak 32 is spaced from an adjacent peak 32 in a direction parallel to a longitudinal axis X of the body 29 . In the embodiment, the peaks 32 define rounded fins and the valleys 34 are also rounded. The undulation structure 30 can be separated by tap connection bases 36 that are directly adjacent thereto. The undulation structure 30 increases the effective track path and reduces the chances of dielectric failure.
Alternate contoured geometries for the undulation structure 30 can be used. For example, FIG. 4A shows the undulation structure 38 having half-moon shaped peaks 40 with alternating valleys 42 . FIG. 4B shows undulation structure 44 having half-moon shaped valleys with alternating peaks 48 . FIG. 4C shows undulation structure 50 of saw-tooth shape having alternating peaks 52 and valleys 54 . FIG. 4D is shows undulation structure 56 of sine wave shape having alternating peaks 58 and valleys 60 . FIG. 4E is shows undulation structure 62 of cosine wave shape having alternating peaks 64 and valleys 66 . Other shapes can be used with any amplitude and period.
The process of adding the undulation structure to the dome structure of the dry type cast coil transformer allows a greater track path to be established while using a horizontal casting method with the voltage taps facing upwardly. Currently, increasing the track path requires the transformer coil to be cast with the voltage adjustment taps down or horizontal to create bushings. The undulation structure also provides an improved cooling surface when transformer is in operation.
To minimize the volume of epoxy and thus reduce the risk of cracks in a cast coil transformer, the epoxy can be removed between the electrically connected sections and then, if desired, any of the undulation structures mentioned above can be applied to the dome structure 26 .
FIG. 5 shows a conventional mold 68 for molding a conventional cast coil transformer 70 having a dome structure 72 that includes the conductor leads (taps) 74 . The shape of the dome structure 72 results from the mold shape that is opened to the top side 76 (related to the casting and curing position) where the epoxy mixture is introduced into the mold 68 .
With reference to FIG. 6 , instead of the mold structure which has an open top, in accordance with an embodiment, the mold 68 ′ includes additional dome mold structure, generally indicated at 78 , that limits the entire shape of the dome structure 26 on the top side 76 . The dome mold structure 78 ensures that the epoxy 80 can only fill out the necessary volume located around the tap connection bases 86 ( FIG. 9 ) for the taps 74 . More particularly, the dome mold structure 78 includes mold features 79 adjacent to the bases 86 that prevent epoxy from accumulating thereby reducing the amount of epoxy adjacent to the bases 86 . A special requirement is the possibility of adaption for the whole measurements spectrum of the coil outer diameter, the coils maximum height and the position of the taps but without the creation of a large variety of different dome mold parts.
To fulfill the requirement of the independence on the outer diameter of the coil, the dome mold structure 78 possesses a basic shape along the entire coil height (as in the conventional construction) but decreased to a minimum. Generally, the shape of the dome structure 26 (without considering the taps 74 ) should be part of a circle, similar to imitate the shape of the coil, and should minimize the epoxy volume. Some possible shapes of the dome structure 26 are shown in FIGS. 7A-7D . For example, FIG. 7A shows the dome structure 26 ′ having a three-sided shape, FIG. 7B shows the dome structure 26 ″ having a five-sided shape, FIG. 7C shows the dome structure 26 ″′ having circle shape with an offset, and FIG. 7D shows the dome structure 26 ″′ having a three-sided shape with rounded edges. Other shapes are possible that reduce the volume of the dome structure.
The choice of the best shape of the dome structure 26 depends on the spectrum of the outer diameters and also the fabrication method may be a consideration. Furthermore, to fulfill the requirement of different heights, tap positions and their amount, the dome mold structure 78 needs to be parted in several sectors along the height. The amount of sectors depends on the amount of taps 74 and/or tap regions (if several taps are located very close it makes sense to combine their bases to one) and their positions (if the end taps are not very close to the face side of the coil a spacer between the end tap mold and the face sides is necessary). The general transformer configuration consists of two end taps and an area of several taps in the center of the coil. Several transformer configurations are shown in FIGS. 8A-8D . For example, FIG. 8A shows two end-tap molds 82 and a spacer 84 , FIG. 8B shows two end-tap molds 82 and three spacers 84 , FIG. 8C shows two-end tap molds 82 , one center-tap mold 82 ′, and two spacers 84 , and FIG. 8D shows two-end tap molds 82 , one center tap mold 82 ′, and four spacers 84 .
The tap molds 82 , 82 ′ are meant to be the same for every coil and shall be used many times. The spacers 84 just carry the shape of the dome structure 26 and may include the undulation forming structure 18 of FIG. 2 . The spacers 84 can have different lengths depending on the position and amount of taps and the total length of the coil. The spacers 84 could be extruded aluminum profiles with shape of the dome structure 26 that allows a very easy and fast fabrication of the spacers. All fabricated parts can be stored and used again in later cases. To minimize a high variety of spacers 84 , standardized coil length and tap position could be defined.
FIG. 9 shows a cast coil transformer 28 ′ having a dome structure 26 (without undulation structure) that results from the mold 68 ′ of FIG. 6 . In the embodiment, the dome structure 26 has a minimized volume along the whole coil height and has three tap connection bases 86 for the taps 74 which also have a minimum of volume. The tap connection bases 86 are raised with respect to an adjacent upper surface 88 of the dome structure, thus reducing the volume of the dome structure 26 due to the material omitted adjacent to the bases 86 .
In the embodiment of FIG. 10 , the dome structure 26 ′ includes the undulation structure 30 ′ that is on a plane A that is below a plane B of the tap connection bases 86 ′, 86 ″ so that the tap connection bases are raised with respect to the undulation structure. As disclosed above, the undulation structure 30 ′ increases the effective track path and reduces the chances of dielectric failure. The volume of epoxy cast is also reduced due to the recessed undulation structure 30 ′.
The tap connection bases 86 can have different shapes as well. The configuration of the bases 86 basically depends on the best way to fabricate the bases. Some configuration of the bases can include a cone shape (especially for the end taps), a pyramid shape, rectangular, square, oval conic shape or other shapes. FIG. 11 shows a transformer mold 68 ′ having a dome mold structure 78 ″ in accordance with another embodiment to produce end located, generally oval-shaped bases 86 ′ and a central, generally rectangular shaped base 86 of the dome structure 26 ″ of a cast coil transformer 28 ″ of FIG. 12 .
The change of shape of the dome structure 26 down to a minimum volume and the addition epoxy tap connection bases 86 just surrounding the taps 74 reduces the volume and thus the cost of the coil transformer. Furthermore, the minimized thickness of the dome structure 26 reduces the risk of cracks which may occur after curing.
The foregoing preferred embodiments have been shown and described for the purposes of illustrating the structural and functional principles of the present invention, as well as illustrating the methods of employing the preferred embodiments and are subject to change without departing from such principles. Therefore, this invention includes all modifications encompassed within the spirit of the following claims. | A dry type cast coil transformer ( 28 ) includes a hollow body ( 29 ), a dome structure ( 26 ) extending from the body, and undulation structure ( 30 ), defining at least a portion of an outer surface of the dome structure, constructed and arranged to increase an electrical track path in the dome structure. | 7 |
FIELD OF THE INVENTION
The present invention is directed to hosiery, and, more particularly, to crinkle or slouch hosiery.
BACKGROUND OF THE INVENTION
Ladies and childrens socks having tops with a finished appearance to them have become increasingly popular in recent years. In particular, socks which may be pushed down about the ankles are considered fashionable. Socks of this type are generally referred to as "slouch" socks or sport socks. The top portion of the sock generally has a finished look such that it may be worn with shorts, gauchos, and the like.
Such socks are generally not available in sheerer hosiery. First, they are only constructed with heavy yarns resulting in a thick and bulky sock. Hosiery, such as pantyhose, knee-highs, thigh-highs, etc., formed of lighter or sheerer yarns have generally not been available or provided with a crinkle look. This is because of the tendency for the sheerer yarns to slide down the leg rather than hold their position. Once the upper portion of the sock has been pushed down to achieve the slouched effect, there is nothing to keep the ankle portion from working its way down into the shoe, causing discomfort and reducing the slouched appearance. This problem would even be exacerbated in sheerer or lighter weight socks.
Thus, there exists a need for an article of hosiery of the type described above which achieves a unique appearance and which does not allow the lower portion to slide down on the leg or ankle. There exists a need for a hosiery article having unique and visually appealing ribs in a portion thereof. Further, there exists a need for such an article which is cost effective to manufacture.
SUMMARY OF THE INVENTION
The present invention is directed to a decorative and functional article of hosiery, such as anklets, thigh-highs, knee-highs, or pantyhose. The hosiery includes a tubular upper portion adapted to be worn about the leg or ankle. The upper portion has an upper elastic band or web and a lower band or anchor with a relatively wide ribbed portion therebetween. The lower band is provided at the lower end of the ribbed portion and protrudes exteriorly of the lower portion. So formed, the lower band serves as an anchor to prevent the ribbed portion of the hosiery from sliding downwardly after the "slouch" appearance is achieved. The upper portion is pushed down toward the lower end of the upper portion, to form the slouch or crinkle band. The lower band anchors the crinkled portion in place and prevents sliding down the leg or into the shoe. Preferably, the lower band is ribbed and/or elasticized.
The upper band is formed at the upper end of the ribbed portion. The upper band is preferably elasticized and ribbed, and serves to frictionally engage the leg, and thereby hold the upper end of the upper portion in a selected position on the leg spaced from the lower band to form the crinkle section.
The ribbed portion includes a plurality of spaced-apart, relatively wide ribs formed along its length to provide a desirable visual effect. The wide ribs provide an attractive crinkled or twisted appearance when the upper band is slid down closer to the lower band.
An object of the present invention is to provide a decorative and functional article of hosiery.
An object of the present invention is to provide a hosiery article, as described above, which may be worn in a slouch or crinkled position and which will maintain the selected position on the leg or ankle.
Yet another object of the present invention is to provide a hosiery article, as mentioned above, having crinkled ribs along a selected portion, providing a unique and desirable visual effect.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front elevational view of a substantially flattened sock according to the present invention.
FIG. 2 is a side cross-sectional elevational view of the sock of the present invention taken along the line 2--2 of FIG. 1.
FIG. 3 is a side elevational view of the sock of the present invention shown in a crinkled position and in conjunction with a shoe.
FIG. 4 is a diagram of the stitch construction of the upper leg portion of the sock showing a portion of the construction of the ribs.
FIG. 5 is a diagram of the stitch construction of the upper and lower bands.
FIG. 6 is a fragmentary view of the upper portion of the sock showing a rib formed thereon.
FIG. 7 is a side elevational view of a pantyhose including a sock according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIGS. 1-3, a crinkled hosiery article according to the present invention is shown therein and generally denoted by the numeral 10. Hosiery article 10 includes upper leg portion 20 and lower foot portion 40. Upper band 50 is integrally formed with the upper end of upper portion 20. Lower band 52 is integrally formed between upper portion 20 and lower portion 40.
Lower portion 44 is formed from tubular body portion 44 which is closed at its lower end by stitching 46. In the design of FIGS. 1-3, lower portion 40 is preferably sized and shaped to receive the portion of a foot extending from the mouth 62 of a shoe 60 to the end of the wearer's toes. Lower portion 40 may be formed longer than shown in the figures in order to accommodate a shoe having a higher mouth, such as a boot, or to form other types of hosiery as discussed below.
Upper portion 20 includes tubular body 24 having outwardly projecting, twisted, decorative ribs 26 formed thereon (as best seen in FIG. 6). Upper portion 20 has a length of at least about 6 inches long stretched or about 4 inches long relaxed, in order to achieve the desired crinkle effect. Preferably, the upper portion is between 6 inches and 18 inches in length stretched or between 4 inches and 10 inches long relaxed and not finished, depending on the application.
Upper band 50 is preferably double-ply, ribbed, and elasticized so as to provide sufficient frictional engagement with the wearer's leg to hold the upper end of the upper portion in place while remaining comfortable to the wearer.
Lower band 52 is preferably double-ply, ribbed, and elasticized. Lower band 52 surrounds the upper end of lower portion 40. Preferably, lower band 52 extends downwardly from stitching 48, thereby forming a protruding, downwardly extending cuff. Lower band 52 is preferably elasticized so as to provide a sufficient frictional engagement with the wearer's leg to hold the upper end of the lower portion in place while remaining comfortable to the wearer.
With particular reference to FIG. 3, hosiery article 10 may be used as follows. In typical fashion, the hosiery article is placed on the wearer's foot and a shoe is placed over the hosiery article. The lower portion is preferably sized such that the upper end thereof extends just to or above the mouth 62 of shoe 60 when the shoe is placed on the foot. Lower band 52 remains outside of the shoe. Lower band 52 flares or protrudes outwardly and surrounds mouth 62. Upper band 50 may be pushed down the wearer's leg, causing upper portion 20 to crinkle as shown in FIG. 3. It will be appreciated that, because lower band 52 is braced against the mouth of the shoe, the lower end of upper portion 20 is anchored and will not be displaced downwardly by the aforementioned crinkling step. Furthermore, because of this bracing, upper portion 20 will resist the common tendency to migrate down into the shoe due to the mechanics of walking. Because lower band 52 is elasticized, it will generally be unnecessary to put on the shoe prior to crinkling upper portion 20, as the elasticity will serve to at least temporarily anchor the lower end thereof. However, it should be noted that because lower band 52 flares outwardly, in the design shown in FIGS. 1-3 the elasticity therein may be reduced or eliminated as desired and the lower band will still serve to anchor the hosiery article while the shoe is on.
While the hosiery article of the present invention has been shown for use with a shoe having a mouth proximate the wearer's ankle, the hosiery article may be adapted for use in other applications. For example, lower portion 44 may be extended to accommodate a shoe having a higher mouth, such as a boot, in which case lower band 52 will anchor the hosiery article against the mouth of the boot. Lower portion 44 may be further extended so that lower band 52 and upper portion 20 may be pulled over the wearer's knee and even as high as the wearer's thigh, forming a decorative thigh-high. The elasticity of the lower band in these applications serves to hold the lower end of the upper leg portion in place.
In a further embodiment, shown in FIG. 7, a hosiery article 110 according to the present invention is integrally formed with leggings 112, thereby forming tights or pantyhose 111. Hosiery article 110 includes upper band 150, lower band 152, upper portion 120, lower portion 140, and ribs 126, corresponding to elements 50, 52, 20, 40 and 26 of the first embodiment.
With the aforementioned overall construction and purposes in mind, the following knitting procedures and yarn construction are preferred for forming hosiery article 10 according to the present invention. Preferably, the upper and lower ribbed bands are formed using a 2×3 (i.e., the first two needles up or engaging the yarn and the next three needles down, and so forth) double ply. Upper portion 20 is formed using a 20×20 positive float (i.e., the first 20 needles up or active and the next 20 needles down, and so forth) which provides a wide, crinkled, rib pattern. The lower portion is formed using all needles up, except on a textured or patterned fabric as discussed below.
Preferably, a cylinder and dial machine is used, with four feeds being used. An example of a suitable machine is the Lonati L404 with four feeds electronic selection. This machine is a 400-needle, 75-gauge machine (75 gauge meaning the thickness of all flat parts, including needles, sinkers, cylinder jacks and dial jacks), often referred to as a fine gauge knitting machine.
The knitting procedure begins with a standard make-up procedure using dial jacks and a 1×3 needle selection (one needle up and three needles down) to form the loops on the dial. By using a 1×3 needle selection in conjunction with the dial jack, a loop is formed over every two dial jacks. This procedure serves to hold the fabric for the plying or doubling of the upper band. The needles of the 1×3 selection go up between every two jacks. The yarn is laid over the dial jacks and the needles pull the yarn down. As the needles go below the dial jacks, the needles hold the yarn to form a loop around the two dial jacks.
Next, a 2×3 needle selection is chosen. With reference to FIG. 5, for the 2×3 needle selections of the upper and lower bands, one end of about 70 to 100 denier textured nylon, preferably 100 denier, is provided at each feed, elements 1, 2, 3, and 4 being provided at feeds #1, #2, #3, and #4, respectively. One end of double covered lycra 1A is additionally provided at feed #1 so that the courses formed at feed #1 are plated. The lycra yarn 1A floats behind the three needles that are down and forms float loops at those needles rather than knitted loops. The two needles that are up form knitted loops, thereby knitting the lycra yarn 1A into the loops. By using this selection, the lycra yarn that is not knitted into loops tends to draw together because less yarn is required to pass behind the needles than to form a knitted loop. In this way, a ribbed effect is achieved, the two needles that are up forming the actual rib. The foregoing procedure is executed on feed #1 only, as a clear float selection. The clear float selection may be achieved by leaving the tuck cam and the clear cam in the "in" position. All of the needles in the remaining feeds are up.
Next, the dial bits and needles are used to form the second ply of the double-ply 2×3 upper band. Using a 1×1 positive float needle selection (i.e, one needle up and one needle down at sinker level) in conjunction with the dial jacks, the loops are shed from the dial. A needle is brought up between each dial jack. As the needles go back down and the dial jacks go back inside the dial, a loop is formed. The needles tie the fabric together (stitching 28), thereby forming a double or plied upper band.
For the 20×20 positive float selection of the upper portion, one end of double covered lycra 1B is provided at feed #1, one end of single covered lycra 3B is provided at feed #3, and one end of about 70 to 100 denier textured nylon, preferably 100 denier, is provided at each of feeds #2 and #4 (denoted as elements 2B and 4B, respectively). The two ends of nylon 2B, 4B are preferably textured yarns of the same twist direction, causing the ribs of the upper portion to have a torque effect resulting in a desirable crinkled or twisted appearance.
With reference to FIG. 4, following the formation of the upper band, a 20×20 positive float selection is selected on feeds #1 and #3 only. That is, twenty consecutive needles are up, followed by 20 consecutive needles down and so forth at feeds #1 and #3, while all of the needles at feeds #2 and #4 are up. This selection is achieved at feeds #1 and #3 by leaving the tuck cams in and bringing the clear cams out. By doing this, the needles that are down are taken out of action (i.e., there is no fabric on these needles at all). The lycra yarns 1B, 3B that are floated in on this selection are not knitted into a loop because the needles are out of action. The lycra yarns lay unknitted or behind the needles and tend to draw together.
The foregoing selection produces a wide ribbed effect. Moreover, the ribs thus formed are crinkled or twisted. It has been found that the desired effect may be achieved using as many as 20 successive float loops or as few as 10 successive float loops. The resulting stitch construction is shown in FIG. 4. Note that, for clarity, FIG. 4 only shows the middle twenty stitches, there being ten float loops to the right of the construction shown and ten knit loops to the left of the construction shown. Every other course consists of twenty knit loops, followed by twenty float loops, followed by twenty knit loops, and so forth. The remaining courses consist of continuous knit loops with no float loops. It is not necessary that there be an equal number of knit loops and float loops. For example, a 15×15 needle selection could be used.
After the 20×20 positive float upper portion has been knitted, the dial jacks are brought back out to form the loops for the lower 2×3 band. By using the dial again as discussed in the formation of the upper band, the second 2×3 band is flared outward and formed in a double ply, the ends of the ribbed fabric joined by stitching 48. The lower band is formed using the procedure described above for forming the upper band, the stitch construction being as shown in FIG. 5.
Suitable nylon yarns include 70/34 textured nylon. Suitable lycra yarns include 3650 double covered lycra and 4034 single covered lycra.
Lower portion 44 is formed using all needles in the machine in conjunction with yarns from all feeds knitted on every loop, except on a textured or patterned lower portion. On a textured or patterned fabric, selective knitted loops are used to form the pattern.
The present invention may, of course, be carried out in other specific ways than those herein set forth without departing from the spirit and the essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein. | A hosiery article having a tubular upper leg portion, a lower foot portion, and a lower band interposed between the upper and lower portions. The lower band is operative to maintain the position of the upper portion relative to the mouth of a shoe. In this way, the band allows the upper portion of the hosiery article to be compressed without allowing the upper portion to enter the shoe. Preferably, the lower band protrudes outwardly. Additionally, an upper band is provided at the upper end of the upper portion to maintain the upper portion in a compressed position.
The upper leg portion is formed with a plurality of wide, crinkled ribs therein, providing a unique and desirable appearance. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is a divisional application of and claims the benefit of and priority to U.S. patent application Ser. No. 12/486,819, filed on Jun. 18, 2009, the entire contents of which are incorporated herein by reference.
[0002] BACKGROUND
[0003] 1. Technical Field
[0004] The present disclosure relates to a surgical staple for use in surgical procedures. More particularly, the present disclosure relates to a surgical staple and a staple assembly configured to accommodate various thicknesses of tissue by assuming a box configuration upon formation through tissue. The present disclosure also relates to a method of stapling tissues of various thicknesses with a single, uniform size staple.
[0005] 2. Background Of Related Art
[0006] During various surgical procedures it is often necessary to secure one or more tissue sections together or to secure auxiliary structures such as, for example, mesh, buttress material, etc. to tissue. This is typically accomplished by driving a conventional staple, having a backspan and a pair of legs extending from the backspan, through the tissue and/or through the auxiliary structure. Once the conventional staple has been driven through the tissue, the ends of the legs are engaged with an anvil of the type typically having a pair of arcuate anvil pockets. This engagement causes the ends of the legs to be bent or recurved back towards the tissue to secure the tissue sections together and/or to secure the auxiliary material to the tissue. These bent or recurved portions of the staple legs are the tissue clenching portions of the legs.
[0007] When attempting to secure relatively thick sections of tissue together or auxiliary material to a relatively thick tissue section, the sizing of the conventional staple is critical to ensure sufficient leg lengths to traverse the tissue. Insufficient leg lengths will result in incomplete stapling of the tissue.
[0008] Further, when attempting to secure relatively thin sections of tissue together, or auxiliary material to the relatively thin tissue section, the sizing of the conventional staple is selected to ensure that there is not an excess of leg length. Excess leg length may result in the clenching portions of the legs projecting substantially away from the tissue as well as causing the ends of the leg to recurve back into and penetrate the tissue.
[0009] Therefore, it is desirable to provide a staple having a leg length sufficient for various tissue thicknesses expected to be encountered. It is further desirable to provide a box shaped staple capable of being formed such that the clenching portions of the legs lie parallel to and flush against the tissue to be secured. It is still further desirable to provide a box staple assembly incorporating a staple plate to increase the bearing area of the staple against the tissue and shield the tissue from the ends of the staple legs.
SUMMARY
[0010] There is disclosed a box staple including a backspan and a first leg extending from the backspan. The first leg is divided into a first traversing leg portion and a first linear clenching leg portion by a first bend. A second leg also extends from the backspan and is divided into a second traversing leg portion and a second linear clenching leg portion by a second bend. At least one of the first and second linear clenching leg portions is oriented parallel to the backspan. In one embodiment, both the first and second linear clenching leg portions are oriented parallel to the backspan.
[0011] At least one of the first and second traversing leg portions is oriented perpendicular to the backspan. In a specific embodiment, both the first and second traversing leg portions are oriented perpendicular to the backspan.
[0012] In one embodiment, a combined length of the first and second clenching leg portions is less than an overall length of the backspan. In an alternative embodiment, the combined length of the first and second clenching leg portions is equal to an overall length of the backspan. In a specific embodiment, the combined length of the first and second clenching leg portions is greater than an overall length of the backspan.
[0013] There is also disclosed a box staple assembly for use in tissue which generally includes a backspan and first and second legs extending from the backspan. The first leg is divided into a first traversing leg portion and a first linear clenching leg portion by a first bend. The second leg is also divided into a second traversing leg portion and a second linear clenching leg portion by a second bend. A staple plate is positioned on the first and second legs between the backspan and the first and second linear clenching leg portions. At least one of the first and second linear clenching leg portions is oriented parallel to the staple plate.
[0014] The staple plate has first and second holes to receive the first and second traversing leg portions respectively. An overall length of the staple plate is greater than an overall length of the backspan and the distance between the first and second holes is substantially equal to the overall length of the backspan.
[0015] There is also disclosed a method of forming a box staple through tissue including the step of providing a box staple of having a backspan, a first leg extending from the backspan and including a first bend zone located between the backspan and a first end of the first leg, and a second the leg extending from the backspan and including a second bend zone located between the backspan and a second end of the second leg. The first and second ends of the first and second legs are driven through a tissue section. The first leg is impacted in the first bend zone with a first angled portion of a first anvil to form a first bend within the first bend zone and dividing in the first bend zone into a first traversing leg portion and a first linear clenching leg portion.
[0016] The method further includes the step of impacting the first linear clenching leg portion with a first finishing surface of the first anvil to orient the first linear clenching leg portion parallel to the backspan.
[0017] The method further includes the step of impacting the second leg in the second bend zone with a second angled portion of a second anvil to form a second bend within the second bend zone and dividing the second bend zone into a second traversing leg portion and a second linear clenching leg portion.
[0018] The second linear clenching leg portion is impacted with a second finishing surface of the second anvil to orient the second linear clenching leg portion parallel to the backspan.
[0019] In one embodiment of the disclosed method, the first and second ends are driven through tissue such that the backspan engages an upper surface of the tissue.
[0020] In a further embodiment of the disclosed method, a staple plate is positioned over the first and second legs and engages an underside of the tissue prior to the step of impacting the first leg in the first bend zone.
[0021] In a particular embodiment, the first linear clenching leg portion is oriented parallel to the staple plate.
DESCRIPTION OF THE DRAWINGS
[0022] Embodiments of the presently disclosed box staple and box staple assembly are disclosed herein with reference to the drawings, wherein:
[0023] FIG. 1 is a side view, partially shown in section, of one embodiment of a disclosed box staple formed through a pair of tissue sections;
[0024] FIG. 2 is an end view taken along line 2 - 2 of FIG. 1 ;
[0025] FIG. 3 is a top view taken along line 3 - 3 of FIG. 1 ;
[0026] FIG. 4 is a bottom view taken along line 4 - 4 of FIG. 1 ;
[0027] FIG. 5 is a side view, partially shown in section, of the box staple of FIG. 1 , inserted through the pair of relatively thick tissue sections, immediately prior to formation;
[0028] FIG. 6 is a side view similar to FIG. 5 during formation of the box staple through the pair of relatively thick tissue sections;
[0029] FIG. 7 is a side view similar to FIG. 6 after formation of the box staple through the pair of relatively thick tissue sections;
[0030] FIG. 8 is perspective view of the fully formed box staple;
[0031] FIG. 9 is a side view, partially shown in section, of the box staple formed through a pair of relatively thin tissue sections;
[0032] FIG. 10 is a top view taken along line 10 - 10 of FIG. 9 ;
[0033] FIG. 11 is an end view taken along line 11 - 11 of FIG. 9 ;
[0034] FIG. 12 is a bottom view taken along line 12 - 12 of FIG. 9 ;
[0035] FIG. 13 is a side view, partially shown in section, of the box staple immediately prior to formation through the pair of relatively thin tissue sections;
[0036] FIG. 14 is a side view similar to FIG. 13 during formation of the box staple through the pair of relatively thin tissue sections;
[0037] FIG. 15 is similar to FIG. 14 after formation of the box staple through the pair of relatively thin tissue sections;
[0038] FIG. 16 is a perspective view of a box staple assembly including a box staple and a staple plate;
[0039] FIG. 17 is a side view, partially shown in section, of the box staple assembly formed through a pair of relatively thick tissue sections;
[0040] FIG. 18 is an end view taken along line 18 - 18 of FIG. 17 ;
[0041] FIG. 19 is a top view taken along line 19 - 19 of FIG. 17 ;
[0042] FIG. 20 is a bottom view taken along line 20 - 20 of FIG. 17 ;
[0043] FIG. 21 is a side view, partially shown in section, of the box staple assembly immediately prior to formation through the pair of relatively thick tissue sections;
[0044] FIG. 22 is a side view, similar to FIG. 21 , during formation of the box staple assembly through the pair of relatively thick tissue sections;
[0045] FIG. 23 is a side view, similar to FIG. 22 , after formation of the box staple assembly through the pair of relatively thick tissue sections;
[0046] FIG. 24 is side view, partially shown in section, of the box staple assembly formed through a pair of relatively thin tissue sections;
[0047] FIG. 25 is a top view taken along line 25 - 25 of FIG. 24 ;
[0048] FIG. 26 is a bottom view taken along line 26 - 26 of FIG. 24 ;
[0049] FIG. 27 is an end view taken along line 27 - 27 of FIG. 24 ;
[0050] FIG. 28 is a side view, partially shown in section, of an alternate embodiment of a staple assembly including a staple and an arcuate staple plate formed through a pair of relatively thick tissue sections; and
[0051] FIG. 29 is a side view, partially shown in section, of the staple assembly of FIG. 28 formed through a pair of relatively thin tissue sections.
DETAILED DESCRIPTION OF EMBODIMENTS
[0052] Embodiments of the presently disclosed box staple and box staple assembly will now be described in detail with reference to the drawings wherein like numerals designate identical or corresponding elements in each of the several views. As is common in the art, the term “proximal” refers to that part or component closer to the user or operator, i.e. surgeon or physician, while the term “distal” refers to that part or component further away from the user.
[0053] Referring to FIG. 1-4 , and initially to FIG. 1 , there is disclosed an embodiment of a universal or box staple 10 for use in various thickness of tissues. Box staple 10 has the further advantage of providing uniform pressure against the underside of the tissues stapled as described in more detail hereinbelow. Box staple 10 generally includes a backspan 12 and first and second legs 14 and 16 , respectively, extending distally from backspan 12 . Specifically, a proximal end 18 of first leg 14 extends distally from a first end 20 of backspan 12 and a proximal end 22 of second leg 16 extends distally from a second end 24 of backspan 12 . First leg 14 terminates in a tissue penetrating distal tip 26 and second leg 16 terminates in a tissue penetrating distal tip 28 .
[0054] Box staple 10 is formed from a length of material having a generally rectangular cross-section. Box staple 10 can be formed from any number of biocompatible materials such as, for example, stainless steel, titanium, various malleable plastic materials, various bio-absorbable materials etc. When formed from metallic materials such as stainless steel or titanium, box staple 10 can be formed by drawing and cutting a length of metallic wire, stamping box staple 10 from a sheet of metallic material, etc. Likewise, when box staple 10 is formed from a plastic or bio-absorbable material, box staple 10 can be formed by injection molding, carving box staple 10 from a block of plastic material, etc.
[0055] As noted above, box staple 10 is designed for use in tissues of various thicknesses, such as, for example, relatively thick tissues A and B. In order to accommodate the various thickness tissues without excessive or insufficient compression of tissues A and B, first leg 14 has a first bend zone 30 which extends substantially between proximal end 18 and tissue penetrating distal tip 26 of first leg 14 . Depending upon the thickness of the tissues encountered, first leg 14 can be bent at any location within bend zone 30 to accommodate those tissues. This is facilitated by the use of a pair of driven anvils as described in more detail herein below. Second leg 16 also includes a second bend zone 32 which extends substantially between proximal end 22 and tissue penetrating distal tip 28 of second leg 16 .
[0056] When box staple 10 is fully formed through relatively thick tissues A and B, backspan 12 provides uniform compression on an upper surface C of relatively thick tissue section A ( FIGS. 1 and 3 ). First leg 14 is formed with a first bend 34 in first transition zone 30 such that first leg 14 is divided into a first, substantially linear traversing leg portion 36 extending through relatively thick tissues A and B ( FIG. 1 ) and a first substantially linear clenching leg portion 38 lying flush with an underside D of relatively thick tissue section B ( FIGS. 1 and 4 ). It should be noted that, first bend 34 formed between first traversing leg portion 36 and first clenching leg portion 38 is a substantially sharp or abrupt 90° bend in contrast to the relatively gradually curving bends typically associated with prior art staples. Likewise, second leg 16 is formed with a second bend 40 in second bend zone 32 which divides second leg 16 into a second substantially linear traversing leg portion 42 extending through relatively thick tissue sections A and B ( FIGS. 1 and 2 ) and a second substantially linear clenching leg portion 44 lying flush with underside D of relatively thick tissue section B. ( FIGS. 1 and 4 ). Second bend 40 also forms a relatively sharp or abrupt 90° transition between second traversing leg portion 42 and second clenching like portion 44 . By maintaining first and second clenching leg portions 38 and 44 in a relatively linear or straight configuration against underside D of relatively thick tissue section B, first clenching leg portion 38 and second clenching leg portion 44 maintain a uniform compression against underside D without the associated pinching or tip penetration of underside D as is common with the use of conventional staples whose leg distal ends are typically formed into a recurved shape penetrating back into the tissue.
[0057] As best shown in FIG. 1 , when box staple 10 is formed through of relatively thick tissue sections A and B, the length L 1 of backspan 12 is greater than or equal to the combined lengths L 2 and L 3 of first and second linear clenching leg portions 38 and 44 , respectively.
[0058] Referring now to FIGS. 5-7 , and initially with respect to FIG. 5 , the use and formation of box staple 10 with relatively thick tissue sections A and B will now be described. Initially, the dimensions of box staple 10 are chosen such that legs 14 and 16 have overall lengths L 4 and L 5 which are substantially greater than the anticipated combine thicknesses of any tissues to be encountered. Furthermore, each of the overall lengths L 4 and L 5 of first and second legs 14 and 16 , respectively, is greater than half the overall length L 1 of backspan 12 . This ensures sufficient leg length to traverse and secure both relatively thick and thin tissue sections. Box staple 10 is initially driven through relatively thick tissue sections A and B by engaging backspan 12 with a staple driver (not shown) thereby driving first and second tissue penetrating distal tips 26 and 28 , respectively, through tissue sections A and B.
[0059] Referring to FIG. 6 , thereafter, a pair of anvils, such as, for example, first and second driven anvils 50 and 52 , are driven laterally against first and second staple legs 14 and 16 to form box staple 10 through relatively thick tissue sections A and B. First and second driven anvils 50 and 52 generally include respective first and second angled surfaces 54 and 56 and respective first and second finishing surfaces 58 and 60 . First and second angled surfaces 54 and 56 are provided to initially impact or impinge against first and second legs 14 and 16 within the respective first and second bend zones 30 and 32 to initially create first and second bends 34 and 40 . This divides first bend zone 30 of first leg 14 into first traversing leg portion 36 and first linear clenching leg portion 38 . Similarly, this divides second bend zone 32 into second traversing leg portion 42 and second linear clenching leg portion 44 .
[0060] Referring to FIG. 7 , as first and second anvils 50 and 52 are driven to the final position, first and second linear clenching leg portions 38 and 44 engaged by relatively linear finishing surfaces 58 and 60 of driven anvils 50 and 52 , respectively such that first and second linear clenching leg portions 38 and 44 are brought flush into engagement with underside D of relatively thick tissue section B. As noted here in above, when box staple 10 is used in relatively thin tissue sections, the combined lengths L 2 and L 3 of first and second clenching leg portions 38 and 44 , respectively, are substantially less than or equal to the overall length L 1 of backspan 12 .
[0061] Referring now to FIGS. 8-12 , and initially with regard to FIG. 8 , box staple 10 is illustrated in the configuration it assumes when used through a pair of relatively thin tissue sections. Specifically, when box staple 10 is formed through relatively thin tissue sections, each of the lengths L 2 and L 3 of respective first and second linear clenching leg portions 38 and 44 are greater than the overall length L 1 of backspan 12 .
[0062] As shown in FIG. 9 , first and second traversing leg portions 36 and 42 pass through thin tissue sections E and F. First and second the linear clenching leg portions 38 and 44 lie parallel to tissue section F. As best shown in FIG. 10 , backspan 12 engages an upper surface G of tissue section E while first and second linear clenching leg portions 38 and 44 engaged an underside surface H of tissue G.
[0063] As best shown in FIGS. 8 , 11 and 12 , the excess lengths of first and second clenching leg portions 38 and 44 are accommodated by allowing them to lie in parallel relation to each other against underside F of tissue H. Thus, box staple 10 functions as a universal staple suitable for use with both thick and thin tissue sections without risk of penetrating the tissue sections with first and second tissue penetrating distal tips 26 and 28 of respective first and second legs 14 and 16 .
[0064] Referring now to FIGS. 13-15 , in order to form box staple 10 through pair of relatively thin tissue sections E and F, box staple 10 is initially driven through tissue sections E and F. Thereafter, driven anvils 50 and 52 impact staple legs 14 and 16 to initially begin to bend staple legs 14 and 16 . As shown in FIG. 14 , angled faces 54 and 56 of driven staples 50 and 52 initially form bends 34 and 40 to create respective first and second traversing leg portions 36 and 42 and first and second linear clenching leg portions 38 and 44 . Thereafter, with reference to FIG. 15 , finishing surfaces 58 and 60 of driven anvils 50 and 52 engage first and second linear clenching leg portions 38 and 44 to form first and second linear clenching leg portions 38 and 44 against underside H of tissue F and, more importantly, parallel to backspan 12 . Thus, box staple 10 is particularly suited to use with relatively thin tissue sections such that first and second linear clenching leg portions 38 and 44 a lie flush against the tissue to be stapled.
[0065] Referring now to FIGS. 16-20 , and initially with regard to FIG. 16 there is disclosed a box staple assembly 70 including box staple 10 and a pledget or staple plate 72 . Staple plate 72 increases the surface area engaging a tissue being stapled as well as protecting the tissue from engagement with staple legs 14 and 16 upon crimping of box staple 10 about tissue. Box staple 10 is as described herein above including backspan 12 and legs 14 and 16 extending from backspan 12 .
[0066] Staple plate 72 is substantially rectangular having first and second holes 74 and 76 adjacent first and second ends 78 and 80 , respectively, of staple plate 72 . First and second holes 74 and 76 are configured to receive first and second legs 14 and 16 , of box staple 10 , therethrough. Staple plate 72 has an overall length L 4 which is greater than the length L 1 of backspan 12 ( FIG. 1 ). Additionally, the spacing or length L 5 between holes 74 and 76 is substantially identical to the length L 1 of backspan 12 .
[0067] As best shown in FIGS. 17 and 18 , box staple assembly 70 is provided to secure a pair of tissue sections, such as, for example, tissue sections I and J. Backspan 12 engages an upper surface K of tissue section I ( FIG. 19 ) while an upper surface 82 of staple plate 72 engages a lower surface L of tissue section J ( FIG. 20 ).
[0068] Referring to FIG. 20 , as noted herein above, staple plate 72 protects tissue section J from engagement with first and second clenching leg portions 38 and 44 of first and second legs 14 and 16 , respectively. Specifically, upon formation of staple 10 through tissue sections I and J, staple plate 72 is interposed between tissue section J and first and second clenching leg portions 38 and 44 .
[0069] Referring to FIGS. 21-23 , the use of box staple assembly 70 to secure a pair of relatively thick tissue sections I and J together will now be described. With reference to FIG. 21 , initially, box staple 10 is driven by a staple driver (not shown) toward tissue sections I and J such that first and second legs 14 and 16 penetrate tissue sections I and J until backspan 12 engages upper surface K of tissue section I. Staple plate 72 is positioned against undersurface K of tissue section J and legs 14 and 16 are extended through holes 74 and 76 a staple plate 72 . This brings upper surface 82 of staple plate 72 into engagement with undersurface K of tissue section J.
[0070] With reference to FIGS. 21 and 22 , thereafter, first and second driven anvils 50 and 52 are moved inwardly toward first and second legs 14 and 16 . Upon engagement of first and second angled surfaces 54 and 56 with first and second legs 14 and 16 , first and second legs 14 and 16 are initially bent within respective bend zones 30 and 32 to form first and second bends 34 and 40 within first and second legs 14 and 16 . As noted here in above, first bend 34 divides first leg 14 into first traversing leg portion 36 and first linear clenching leg portion 36 while second bend 40 divides second legs 16 into second traversing leg portion 42 and second linear clenching leg portion 44 . Notably, the extension of first and second legs 14 and 16 through first and second holes 74 and 76 in staple plate 72 facilitate forming bends 74 and 76 at substantially right angles relative to first and second traversing leg portions 36 and 38 of first and second legs 14 and 16 , respectively.
[0071] Finally, with reference to FIG. 23 , engagement of first and second finishing surfaces 58 and 60 of the first and second driven anvils 50 and 52 with first and second linear clenching leg portions 38 and 44 serve to secure first and second linear clenching leg portions 38 and 44 against underside 84 of staple plate 72 thereby securing staple plate 84 against underside L of tissue section J.
[0072] Referring now to FIGS. 24-27 , the use of box staple assembly 70 to secure a pair of relatively thin tissue sections, such as, for example, tissue sections M and N will now be described. The method disclosed herein with respect to relatively thin tissue sections M and N is substantially identical to the method disclosed herein above with respect to relatively thick tissue sections I and J. Initially, with reference to FIG. 24 , staple 10 is driven by a staple driver (not shown) such that first and second legs 14 and 16 are driven through tissue sections M and N until backspan 12 engages an upper surface O of tissue section M ( FIG. 25 ). First and second legs 14 and 16 are then inserted through holes 74 and 76 of staple plate 72 . Thereafter, first and second driven anvils 50 and 52 ( FIGS. 21-23 ) are moved to form first and second linear clenching leg portions 38 and 44 against underside 84 of staple plate 72 ( FIG. 26 ).
[0073] As best shown in FIGS. 26 and 27 , similar to that disclosed herein above with respect to box staple 10 in FIGS. 11 and 12 , first and second linear clenching leg portions 38 and 44 are in a side-by-side and overlapping relation with respect to each other due to the excess lengths of legs 14 and 16 wine used through relatively thin tissue sections M and N. In this manner, the provision of box staple 10 having first and second legs 14 and 16 with overall lengths greater then at least the overall length of backspan 12 allows box staple 10 to function as a universal staple suitable for use with various thicknesses of tissue. As noted herein above, the provision of staple plate 72 provides additional surface bearing area against the tissue section while facilitating forming an abrupt 90 ° bend within first and second legs 14 and 16 .
[0074] Referring now to FIGS. 28 and 29 , while staple plate 72 has been disclosed for use with box staple 10 , staple plate 72 may be formed of a material which allows staple plate 72 to be used with a staple and 90 similar to box staple 10 in situations wherein staple 90 is formed with conventional anvils. As used herein, the term “conventional anvils” refers to those anvils having arcuate anvil pockets resulting in arcuate rather than linear clenching leg portions in the formed staple.
[0075] For example, with reference to FIG. 28 , staple 90 includes a backspan 92 having first and second legs 94 and 96 extending from backspan 92 . In use, staple 90 is driven through relatively thick tissue sections Q and R resulting in first and second traversing leg portions 98 and 100 extending through tissue sections Q and R while backspan 92 engages an upper surface S of tissue section Q. First and second legs 94 and 96 are extended through holes 74 and 76 in staple plate 72 and are clenched against staple plate 72 by arcuate anvil pockets formed in an anvil associated with a conventional stapler (not shown).
[0076] Similarly, with reference to FIG. 29 , when used in conjunction with relatively thin tissue sections U and V, backspan 92 engages an upper surface W of tissue section U while traversing leg portions 98 and 100 extending through tissue sections U and V. Staple plate 72 bears against an undersurface X of tissue section V. First and second linear clenching leg portions 102 and 104 of first and second legs 94 and 96 are formed into a roughly arcuate overlapping relation due to the excess length of legs 94 and 96 .
[0077] It will be understood that various modifications may be made to the embodiments disclosed herein. For example, the legs of the disclosed box staple maybe heat treated at specific points to facilitate the formation of the abrupt 90° bend between the traversing portion of the leg and the linear clenching portion of the leg. Further, alternative embodiments of anvils may be provided to form the substantially right angle within their respective legs. Additionally, the disclosed box staple may be formed from any shape memory alloy such that the right angle between the traversing leg portion and the linear clenching leg portion is formed at a predetermined location along the length of the leg. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto. | A staple is provided having a backspan and a first and second legs extending distally from the backspan. Each of the first and second legs includes a bend dividing each leg into a traversing leg portion and a substantially linear clenching leg portion. A staple plate is positionable over the first and second legs between the backspan and the first and second clenching leg portions. An anvil assembly has first and second movable members which move toward to one another to engage outer surfaces of the first and second clenching leg portions. There is further disclosed a method of forming the staple through tissue. | 0 |
TECHNICAL FIELD
The present invention relates to a transparent substrate bearing a solar-control multilayer stack and also to a multiple glazing unit incorporating at least one such transparent substrate bearing a solar-control multilayer stack.
Solar-control stacks, which are also called antisolar stacks, to which the present invention relates, comprise functional films, such as silver-based films, that reflect infrared radiation, associated with antireflection dielectric coatings that act to reduce reflected light and to control other properties of the multilayer such as its colour, but which also act as tie films and protect the functional films. Solar-control stacks commonly contain two functional films sandwiched between dielectric films. More recently, stacks comprising three functional films have been proposed in order to improve further the solar protection provided while retaining the highest possible light transmission. Each functional film is separated by at least one dielectric coating, such that each functional film is sandwiched between two dielectric coatings. The various films of the stack are, for example, deposited by magnetron sputtering. The present invention is not however limited to this particular film deposition process.
Solar-control stacks are used to produce solar-protection glazing units, or antisolar glazing units, in order to reduce the risk of excessive heating by sunshine, for example of a closed space with large glazed areas, and thus reduce the air-conditioning load in summertime. The transparent substrate then often consists of a glass sheet, but it may also, for example, be formed from a sheet of a plastic such as PET (polyethylene terephthalate), which is then either enclosed between two sheets of glass by means of a film of an adhesive polymer such as a PVB (polyvinyl butyral) or EVA (ethylene/vinyl acetate) in order to form a laminated glazing unit, or enclosed inside a multiple glazing unit.
Thus, the glazing unit must limit the amount of solar energy transmitted, i.e. it must have a relatively low solar factor (SF or g). It must however guarantee the highest possible light transmission (T L ) so as to ensure the inside of the building is satisfactorily illuminated. These requirements, which are somewhat contradictory, stipulate a glazing unit with a high selectivity (S), selectivity being defined as the ratio of the light transmission to the solar factor. These solar-control stacks also have a low emissivity, which allows heat loss by long-wavelength infrared radiation to be reduced. They thus increase the thermal insulation of large glazed areas and reduce energy loss and heating costs during cold periods.
Light transmission (T L ) is the percentage of the incident light flux, under illuminant D65, transmitted by the glazing in the visible range. The solar factor (SF or g) is the percentage of the incident radiant energy that is, on the one hand, directly transmitted by the glazing unit, and on the other hand, absorbed by the latter and then reemitted, relative to the glazing unit, in the opposite direction to the energy source.
These antisolar glazing units are in general multiple glazing units such as double or triple glazing units in which the glass sheet bearing the stack is associated with one or more other glass sheets that are also optionally coated, the solar-control multilayer stack making contact with the internal cavity between the glass sheets.
In certain cases, it is necessary to carry out an operation in order to mechanically strengthen the glazing unit, for instance thermal tempering of the one or more glass sheets, so as to increase the ability of the unit to withstand mechanical stresses. Optionally, it is also possible, for particular applications, to give the glass sheets a relatively complex curvature by way of a high-temperature bending operation. In the processes used to manufacture and shape glazing units, there are certain advantages to carrying out these heat-treatment operations after the substrate has been coated, instead of coating a previously treated substrate. These operations are carried out at a relatively high temperature, at which temperature the functional film, based on a material that reflects infrared, for example silver, tends to deteriorate and lose its optical properties and its properties with respect to infrared radiation. These heat treatments especially consist in heating the glass sheet to a temperature above 560° C., for example to a temperature between 560° C. and 700° C., and especially to between 640° C. and 670° C., in air, for about 6, 8, 10, 12 or even 15 minutes, depending on the type of treatment and the thickness of the sheet. In the case of a bending treatment, the glass sheet may then be bent to the desired shape. In contrast, the tempering treatment then consists in suddenly cooling the flat or curved surface of the glass sheet, using jets of air or a coolant, in order to mechanically strengthen the sheet.
In the case where it is necessary for the coated glass sheet to undergo a heat treatment, it is necessary to take very particular precautions when producing the stack structure, because it must be able to withstand a tempering and/or bending heat treatment, this property sometimes being referred to below by the term “temperable”, without losing its optical and/or energy properties, which are the reason it exists in the first place. In particular, it is necessary to use dielectric materials, in the form of dielectric coatings, which can withstand the high temperatures of the heat treatment without undergoing any undesirable structural changes. Examples of materials that are particularly suited to this role are mixed zinc tin oxide, and especially zinc stannate, silicon nitride and aluminium nitride. It is also necessary to take care that the functional films, which are for example silver-based, are not oxidized during the treatment, for example by ensuring that, when the stack is treated, sacrificial layers are in place, these layers oxidizing instead of the silver and thus gettering free oxygen.
It is also desirable for the glazing units to meet certain aesthetical criteria in terms of light reflection (R L )—i.e. the percentage of the incident light flux, under illuminant D65, reflected by the glazing unit in the visible range—and colour in reflection and transmission. Market demand is for glazing units that have a relatively low light reflection, but not too low in order to avoid the “black hole” effect when a building is viewed under certain dim lighting conditions. Furthermore, combining a high selectivity and a relatively low light reflection sometimes leads to purple tints in reflection, which are not very aesthetically pleasing.
Antisolar glazing units are also used in the automotive glazing field, for example as windscreens, but also in the other glazing units of a vehicle, such as side windows, rear windscreens, or in the roof of the vehicle. In this field, glazing units are often laminated, i.e. the substrate bearing the stack is associated with another transparent substrate, optionally also bearing a stack, by way of an adhesive plastic film generally made of PVB, the antisolar stack being placed inside the laminated unit in contact with the PVB. Vehicle windows must generally be curved to match the shape of the vehicle. When the substrate is a glass sheet, the bending operation is carried out at a high temperature and the substrate equipped with its stack is then subjected to a heat treatment similar to the tempering treatment described above, whether it is rapidly cooled or not, and is in addition subjected to a shaping operation while the substrate is still at a high temperature.
To reduce the amount of heat that penetrates, through the glazing unit, into the premises or vehicle, the amount of invisible heat-producing infrared radiation passing through the glazing unit is reduced by reflecting this radiation. This is the role of the functional films based on a material that reflects infrared radiation. They are an essential element of the solar-control stack.
PRIOR ART
A number of solutions have been proposed to improve solar protection while preserving maximal light transmission, but no solution has provided a completely satisfactory glazing unit that combines optimal optical and thermal properties with stability during manufacture.
Patent application WO 2009/029466 A1, in the name of PPG Industries, describes a laminated glazing unit, for an automotive vehicle, in which a glass sheet bears a stack comprising three functional silver-based films. Starting from the glass sheet bearing them, each silver film is thinner than the preceding one. This document describes a stack with a high light transmission, which can be used to form the windscreen of an automotive vehicle. However, the selectivity of this stack is relatively low.
Patent application EP 645 352 A1, filed by Saint-Gobtain Glass, describes an antisolar glazing unit the stack of which comprises three silver films of increasing thickness, starting from the glass. However, according to Examples 1 and 2 of this document, either the selectivity is relatively low, or the colour in reflection is relatively unstable and highly sensitive to fluctuations in thickness during manufacture, or to the lack of transverse uniformity. Specifically, to obtain an industrially acceptable stack, not only must the thicknesses of the functional films be fixed, but the thicknesses of the dielectric coatings must also be adjusted. There are a great many ways to do this and document EP 645 352 A1 does not teach how to obtain the best possible results.
Patent application WO 2010/037698 A1, filed by Saint-Gobain Glass, attempts to solve the problem of stability during manufacture. For this purpose it describes an antisolar glazing unit having a stack comprising at least three silver films the geometric thicknesses of which have central symmetry. This arrangement is intended to improve manufacturing stability uniquely with regard to parallel movements of the dielectric coatings (in this case, the thicknesses of all the dielectric coatings increase or decrease together by the same amount). However, thickness variations may have a cumulative or decumulative effect on any fluctuation in tint. In industrial practice, the deposition processes used to deposit the various dielectric coatings are independent of one another, it is therefore necessary to ensure a good tint stability individually for each thickness variation while also taking account of variations in the thicknesses of the functional films. Furthermore, this stack has a lower selectivity. Thus, the nub of the problem is how to keep a good stability while maximizing selectivity. In addition, the examples relate to stacks comprising four functional films.
SUMMARY OF THE INVENTION
One of the objectives of the invention is to provide a transparent substrate bearing a solar-control multilayer stack that provides effective solar protection with a high selectivity while completely overcoming the drawbacks of the prior art.
Another objective of the invention is to provide a coated substrate which has a pleasing appearance, both in transmission and in substrate-side reflection, and meets commercial requirements, for example especially having a relatively neutral tint.
Another objective of the invention is to make it easier to obtain a coated substrate that has a tint with a good angular stability in reflection, i.e. the amplitude of the tint variation is small or acceptable, without substantially modifying the hue of the tint.
Another objective of the invention is to provide a coated substrate the tint in reflection of which, observed on the substrate side, does not vary much when film thicknesses fluctuate during manufacture of a batch of coated substrates, or when there is a lack of transverse uniformity caused by a variable deposition rate along the cathodes.
Another objective of the invention is to provide a coated substrate that can be easily mass produced on an industrial scale at an advantageous cost price.
The invention relates to a transparent substrate bearing a solar-control multilayer stack comprising three functional films based on a material that reflects infrared radiation and four dielectric coatings, such that each functional film is sandwiched between dielectric coatings, characterized in that, the geometric thickness of the second, counting from the substrate, functional film is larger than the geometric thickness of the first functional film and the geometric thickness of the third functional films is larger than the geometric thickness of the first functional film, and in that the ratio of the optical thickness of the transparent dielectric coating placed between the second and third, counting from the substrate, functional films, to the optical thickness of the final transparent dielectric coating placed on the last functional film, is between 2.0 and 3.2, and in that the ratio of the optical thickness of the transparent dielectric coating placed between the second and third functional films, to the optical thickness of the transparent dielectric coating placed between the first and second functional films, is either between 0.6 and 0.9 or between 1.15 and 1.7.
Surprisingly, respecting the combination of features claimed in claim 1 makes it easier to achieve coated substrates having optical properties that remain very stable during industrial mass production. Interference effects are complex, and the fact that stacks according to the invention contain many films increases the complexity. Fluctuations in film thicknesses during production may lead to the optical properties of the coated substrate being substantially modified. The invention allows this adverse modification of the quality of these industrially mass produced products to be more easily minimized.
In the present description, when the range of given values is contained between two limits, the limits are implicitly included in the given range. Optical thickness is defined as the geometric (physical) thickness of the considered film multiplied by its refractive index. The variation in the refractive index of the various materials as a function of wavelength may differ substantially. In the context of the present invention, the optical thickness of the transparent dielectrics is calculated using the following formula:
optical thickness=d multiplied by n v,
where d is the geometric (physical) thickness of the considered film and n v is a virtual refractive index obtained using the following formula:
n v =(0.6902 ×n (550) 2 )−(0.165 ×n (550))−0.4643
where n(550) is the refractive index of the material at a wavelength of 550 nm.
If a transparent dielectric coating consists of a plurality of films, the total optical thickness of the transparent dielectric coating to be considered is the sum of the optical thicknesses of the various films, calculated as indicated above.
In the present description, unless otherwise indicated, for the sake of simplicity a refractive index of 2.03 has always been used, which refractive index corresponds to dielectric materials such as ZnO, SnO 2 or zinc stannate ZnSnO 4 . However, it will of course be understood that other dielectric materials may be used. By way of example, here are the refractive indices n(550), at a wavelength of 550 nm, of a few of the most commonly used dielectric materials: TiO 2 , n(550)=2.5; Si 3 N 4 , n(550)=2.04; Al 2 O 3 , n(550)=1.8; AlN, n(550)=1.9.
In the present description, unless otherwise indicated, all the optical and thermal property values and ranges of values are given for a double glazing unit formed by: an ordinary 6 mm-thick soda-lime glass pane bearing the film stack; a 15 mm-thick intermediate cavity filled with 90% Ar and 10% air; and another 4 mm-thick uncoated soda-lime glass pane. The coated face of the 6 mm-thick glass pane is located inside the double glazing unit. The reflection observed on the same side as the 6 mm-thick glass pane is denoted “R G ”, i.e. reflection from the “glass side” of the coated glass, whereas the reflection observed on the same side as the 4 mm-thick glass pane is denoted “R F ”, i.e. reflection from the “film side” of the coated glass. Tints are expressed as CIELAB L*a*b* coordinates under illuminant D65, for a 10° observer. The light transmission (T L ) of the stack-less ordinary soda-lime glass is 89% for the 6 mm-thick pane and 90% for the 4 mm-thick pane.
Transparent dielectric coatings are well known in the field of sputter-deposited films. There are many suitable materials and it is pointless to list all of them here. They are in general oxides, oxynitrides or metal nitrides. Among the most common, mention may be made, by way of example, of SiO 2 , TiO 2 , SnO 2 , ZnO, ZnAlO x , Si 3 N 4 , AlN, Al 2 O 3 , ZrO 2 , Nb 2 O 5 , YO x , TiZrYO x , TiNbO x , HfO x , MgO x , TaO x , CrO x and Bi 2 O 3 and mixtures thereof. Mention may also be made of the following materials: AZO, ZTO, GZO, NiCrO x , TXO, ZSO, TZO, TNO, TZSO, TZAO and TZAYO. The term “AZO” refers to aluminium-doped zinc oxide or mixed aluminium-zinc oxide, preferably obtained using a ceramic cathode made of the oxide to be deposited, either in an inert or slightly oxidizing atmosphere. Similarly, the terms “ZTO” or “GZO” refer to mixed zinc-titanium oxide and mixed gallium-zinc oxide, respectively, obtained using ceramic cathodes either in an inert or slightly oxidizing atmosphere. The term “TXO” refers to titanium oxide obtained using a ceramic cathode made of titanium oxide. The term “ZSO” refers to mixed zinc-tin oxide obtained either from a metallic cathode made of the alloy, deposited under an oxidizing atmosphere, or from a ceramic cathode made of the corresponding oxide, deposited either in an inert or slightly oxidizing atmosphere. The terms TZO, TNO, TZSO, TZAO or TZAYO refer to mixed titanium-zirconium oxide, mixed titanium-niobium oxide, mixed titanium-zirconium-tin oxide, mixed titanium-zirconium-aluminium oxide, and mixed titanium-zirconium-aluminium-yttrium oxide, respectively, obtained using ceramic cathodes, either in an inert or slightly oxidizing atmosphere. All the materials cited above may be used to form the transparent dielectric coatings employed in the present invention.
Preferably, the ratio of the optical thickness of the transparent dielectric coating placed between the second and third, counting from the substrate, functional films, to the optical thickness of the final transparent dielectric coating placed on the last functional film, is 2.1 or more, this ratio preferably lying between 2.1 and 3.0, advantageously between 2.1 and 2.7, for example between 2.15 and 2.7, and even more favourably between 2.15 and 2.55.
Preferably, the second, counting from the substrate, functional film is between 12 and 16 nm in thickness, and advantageously between 13 and 15 nm in thickness, and the optical thickness of the first dielectric deposited on the substrate lies between 44 and 86 nm, and advantageously between 46 and 80 nm. These features make it possible to obtain stacks having a tint in reflection, as seen on the substrate side, that is particularly pleasing, with, inter alia, a* values lying between −1.5 and −4 and b* values lying between −3 and −9.
Preferably, each of the three functional films, starting from the substrate, being thicker than the preceding one, that is to say that the thickness of the third functional film, starting from the substrate, is also larger than the thickness of the second functional film. Advantageously, each of the second and third functional films is at least 5% thicker than the preceding one.
Preferably, according to a first embodiment of the invention, the ratio of the optical thickness of the transparent dielectric coating placed between the second and third functional films, to the optical thickness of the transparent dielectric coating placed between the first and second functional films, is 0.9 or less, this ratio preferably lying between 0.65 and 0.9, and advantageously between 0.7 and 0.85.
Stacks obtained according to the first embodiment of the invention are more stable in terms of tint observed in reflection on the stack side. Thus, the stability of the tint during manufacture, expressed by the “Deltacol” value the formula of which is given below, observed on the stack side, is from 1.8 to 2.5, for a selectivity of 1.95 to 2.02. In addition these stacks combine an excellent appearance with good angular stability and also have the advantage that the tint, observed in reflection on the substrate side, is stable during manufacture, this stability, expressed by the Deltacol value, being for example lower than 2.1, even lower than 1.9 and indeed even lower than 1.8.
The stability of the tint in mass-production manufacturing is an important element if production of a consistently high-quality product is to be guaranteed. For the sake of comparison, the variation of the tint in reflection following a fluctuation in film thickness is quantified using a mathematical formula. The tint variation index during manufacture has been called “Deltacol” and is defined by the following relationship:
Deltacol = 0 , 5 x ( Δ a * 1 , 2 + Δ b * 2 , 4 )
in which Δa* and Δb* are the differences between the highest values and the lowest values of a* and b*, respectively, when the thickness of each functional film and each dielectric coating of the stack varies individually plus or minus 2.5%. The values a* and b* are CIELAB (1976) L*a*b* coordinates measured under Illuminant D65/10° observer.
Preferably, according to the first embodiment of the invention, the geometric thickness of the first, counting from the substrate, functional film lies between 9 and 14 nm, preferably between 10 and 13 nm, and advantageously between 11 and 13 nm.
Preferably, according to the first embodiment of the invention, the geometric thickness of the last, counting from the substrate, functional film lies between 11.5 and 17 nm, and preferably between 13 and 16 nm.
Preferably, according to the first embodiment of the invention, the optical thickness of the second transparent dielectric coating, placed between the first and second functional films, lies between 138 and 170 nm, preferably between 140 and 165 nm, and advantageously between 148 and 160 nm.
Preferably, according to the first embodiment of the invention, the optical thickness of the third transparent dielectric coating, placed between the second and third functional films, lies between 101 and 155 nm, preferably between 107 and 147 nm, and advantageously between 117 and 147 nm.
Preferably, according to the first embodiment of the invention, the optical thickness of the final transparent dielectric coating, placed on the last functional film, lies between 40 and 76 nm, preferably between 44 and 71 nm, and advantageously between 50 and 70 nm.
Preferably, according to the first embodiment of the invention, the ratio of the optical thickness of the first transparent dielectric coating, placed between the substrate and the first, counting from the substrate, functional film, to the optical thickness of the final transparent dielectric coating, placed on the last functional film, lies between 0.5 and 1.7, preferably between 0.6 and 1.6, and advantageously between 0.9 and 1.5.
Preferably, according to the first embodiment of the invention, the ratio of the geometric thickness of the third functional film, to the geometric thickness of the second functional film, counting from the substrate, lies between 0.9 and 1.35, preferably between 1.0 and 1.2, and advantageously between 1.1 and 1.2.
Preferably, according to the first embodiment of the invention, the ratio of the optical thickness of the second transparent dielectric coating, placed between the first and second functional films, to the optical thickness of the first transparent dielectric coating, placed between the substrate and the first functional film, counting from the substrate, lies between 1.6 and 3.8, preferably between 1.8 and 3.5, and advantageously between 2.0 and 3.0.
Advantageously, all these features according to the first embodiment are combined to obtain the best possible result.
Respecting these features according to the first embodiment of the invention makes it easy to obtain stacks that, furthermore, have particularly neutral tints in transmission, with b* values that are <3, preferably <2 and even <1.
Preferably, according to a second embodiment of the invention, the ratio of the optical thickness of the transparent dielectric coating placed between the second and third functional films, to the optical thickness of the transparent dielectric coating placed between the first and second functional films is 1.2 or more, this ratio preferably lying between 1.2 and 1.5, and advantageously between 1.2 and 1.4 and indeed favourably lying between 1.2 and 1.3.
Preferably, according to this second embodiment of the invention, the ratio of the optical thickness of the transparent dielectric coating placed between the second and third, counting from the substrate, functional films, to the optical thickness of the final transparent dielectric coating placed on the last functional film, is 2.2 or more, preferably 2.3 or more, and indeed favourably 2.4 or more. In the case of temperable films, it is advantageous for this ratio to be 2.4 or more and favourably it lies between 2.4 and 2.7, and it is moreover advantageous, in this case, in combination with the latter feature, for the ratio of the optical thickness of the transparent dielectric coating placed between the second and the third functional films, to the optical thickness of the transparent dielectric coating placed between the first and the second functional films, also to be 1.3 or more.
The stacks obtained according to the second embodiment of the invention have a better selectivity. The selectivity will possibly be higher than 2.02 or even 2.05. In addition these stacks combine an excellent appearance with good angular stability and also have the advantage that the tint, observed in reflection on the glass side, is stable during manufacture, this stability, expressed by the Deltacol value, being for example lower than 2.1, even lower than 1.9 and indeed even lower than 1.8.
Preferably, according to the second embodiment of the invention, the geometric thickness of the first, counting from the substrate, functional film lies between 8 and 12 nm, advantageously between 9 and 11 nm, and favourably between 10 and 11 nm.
Preferably, according to the second embodiment of the invention, the geometric thickness of the last, counting from the substrate, functional film lies between 16 and 20 nm, advantageously between 17 and 19 nm, and favourably between 18 and 19 nm.
Preferably, according to the second embodiment of the invention, the optical thickness of the second transparent dielectric coating, placed between the first and second functional films, lies between 105 and 150 nm, advantageously between 115 and 136 nm, and favourably between 119 and 132 nm.
Preferably, according to the second embodiment of the invention, the optical thickness of the third transparent dielectric coating, placed between the second and third functional films, lies between 152 and 175 nm, and advantageously between 156 and 175 nm.
Preferably, according to the second embodiment of the invention, the optical thickness of the final transparent dielectric coating, placed on the last functional film, lies between 58 and 82 nm, and advantageously between 67 and 80 nm.
Preferably, according to the second embodiment of the invention, the ratio of the optical thickness of the first transparent dielectric coating, placed between the substrate and the first, counting from the substrate, functional film, to the optical thickness of the final transparent dielectric coating, placed on the last functional film, lies between 0.5 and 1.2, and advantageously between 0.6 and 1.1.
Preferably, according to the second embodiment of the invention, the ratio of the geometric thickness of the third functional film, to the geometric thickness of the second functional film, counting from the substrate, lies between 1.1 and 1.8, and advantageously between 1.2 and 1.6.
Preferably, according to the second embodiment of the invention, the ratio of the optical thickness of the second transparent dielectric coating, placed between the first and second functional films, to the optical thickness of the first transparent dielectric coating, placed between the substrate and the first functional film, counting from the substrate, lies between 1.5 and 2.6, and advantageously between 1.7 and 2.4.
Preferably, the substrate is an ordinary clear or bulk-tinted soda-lime glass sheet. This is the most suitable substrate to base a solar-control glazing on and it may be subjected to a high-temperature heat treatment such as a tempering or bending heat treatment. Advantageously, the substrate is a sheet of extra-clear glass having a light transmission of higher than 90%, even higher than or equal to 91%, and indeed even higher than or equal to 92%. A particularly preferred substrate is the glass sold under the trade name Clearvision® by AGC Glass Europe.
One embodiment of the invention comprises a transparent substrate bearing a multilayer stack the solar factor of which is very low. A substantial amount of heat-producing radiation is also transmitted in the visible. To reduce transmission of this portion of heat-producing radiation and go beyond removing the energy supplied by infrared radiation, it is necessary to reduce the level of light transmission. In this case, the stack is deliberately made to absorb light in order to reduce light transmission. This absorption is obtained by inserting a film of absorbent material somewhere inside the stack, this material possibly being, for example, formed from an absorbing metal, metal oxide, or oxygen-substoichiometric metal oxide, or from an absorbing metal nitride, nitrogen-substoichiometric metal nitride or metal oxynitride. It is also possible simply to increase the thickness of a metal film protecting one or more of the functional films. The light transmission of a double glazing unit such as described above is then advantageously 57% or less.
It is however necessary to exclude, from this embodiment of the invention, the particular case where there are, in the stack, at least two metallic, in particular titanium-based, films that absorb in the visible, each of these films being placed on and making contact with a functional film, which metallic films result in the light transmission of the resulting double glazing unit, after any optional heat treatment, being less than 50%. In this case, the total thickness of the absorbing metal of these absorbent (in the visible) metallic films placed on the functional films is greater than 1.3 nm as measured in the final product, after any optional heat treatment. This particular case is the subject of the international patent application filed on the 25 May 2011 under the number PCT/EP2011/058540 in the name of the Applicant, and it is not included in the scope of the present invention. Stacks according to the present invention make it possible to obtain all the desired properties described above, without an absorbent metallic film being present in their finished, ready for use, state (i.e. after any optional heat treatment).
Preferably, the light transmission T L of the stack according to the invention, when it is fitted in a double glazing unit as indicated above, and after any optional heat treatment, is higher than 51%, advantageously higher than 54% and preferably higher than or equal to 57%. The light transmission of a double glazing unit incorporating a stack according to the invention is for example higher than 58%, 59% or 60%. For temperable/bendable stacks, light transmissions higher than 64% and even higher than 66% have been obtained after heat treatment.
The invention relates to a multiple glazing unit comprising at least one substrate bearing a solar-control multilayer stack such as described above.
Preferably, the light transmission T L of the double glazing unit, such as defined above, is higher than 51%, advantageously higher than 55%, and favourably higher than or equal to 60%.
Preferably, the solar factor of the double glazing unit is 34% or less, preferably 32% or less and advantageously 30.5% or less.
Preferably, the selectivity of the double glazing is higher than 1.95, advantageously higher than or equal to 2, and favourably higher than or equal to 2.05.
The invention also relates to a laminated glazing unit comprising at least one transparent substrate such as described above, assembled with a vitreous material according to the invention by way of an adhesive plastic. Such a glazing unit is advantageously used as a glazing unit in an automotive vehicle, for example as a windscreen.
The invention also relates to a tempered glazing unit bearing an antisolar stack such as described above and having undergone a tempering and/or bending heat treatment at a high temperature above 560° C.
The invention will now be described in greater detail below, but in a non-limiting way, using preferred embodiments.
DESCRIPTION OF EMBODIMENTS
Examples 1 to 13
Examples 1 to 13 were produced in the same way and the structures obtained were similar and even identical (Examples 1 to 10), only the thicknesses changing, as indicated in Table 1.
A 3.2 m by 1 m sheet of 6 mm-thick ordinary clear soda-lime float glass was placed in a low-pressure (about 0.3 Pa) magnetron sputtering coater. A solar-control multilayer stack was deposited on this glass sheet, the multilayer contained the following, in their order.
A first dielectric coating was deposited on the glass sheet. This first coating was formed by two metal-oxide films deposited in a reactive atmosphere consisting of a mixture of argon and oxygen, using metal cathodes. The first metal oxide was a mixed zinc-tin oxide formed using a cathode made of a zinc/tin alloy consisting of 52 wt % zinc and 48 wt % tin in order to form spinel zinc stannate Zn 2 SnO 4 . The second metal oxide was a layer of zinc oxide ZnO having a geometric thickness of about 9.2 nm, deposited using a zinc target. The thickness of the first mixed zinc-tin oxide film was the complement of the thickness of the second ZnO film, so as to achieve the geometric thickness for the first dielectric coating D1 indicated in Table 1 below.
An infrared-reflective functional film IR1 made of silver was then deposited, using a practically pure silver target in an inert atmosphere, for example in argon, on the first dielectric coating D1. The geometric thickness of this film IR1 is given in Table 1.
A 1.4 nm-thick protective film made of sacrificial Ti metal was deposited using a titanium target in an inert atmosphere, directly on the silver film, the sacrificial Ti film having a common interface with the silver film. The oxidizing atmosphere of the plasma used when depositing the following film, described below, oxidizes this sacrificial titanium film. In a stack intended to undergo a tempering, bending and/or toughening heat treatment (the latter being a tempering treatment in which the cooling is less rapid) 2.4 to 3.2 nm of titanium would be deposited under the same conditions. The thickness of the protective film after conversion into an oxide, which was larger than 2.5 nm (value, in oxide, corresponding to the 1.4 nm (geometric thickness) of titanium in the protective film deposited for a non-temperable stack), should be added to the thickness of the following dielectric coating when calculating the ratios according to the invention.
In the same way, the following films were then deposited on the protective film:
a second dielectric coating D2, a second functional film IR2, a 1.4 nm-thick sacrificial Ti film, a third dielectric coating D3, a third functional film IR3, and another 1.4 nm-thick sacrificial Ti film followed by a fourth and last dielectric coating D4.
The second and third infrared-reflective functional films, IR2 and IR3, were formed from silver using a practically pure silver target sputtered in an inert argon atmosphere, in the same way as the film IR1.
The second and third dielectric coatings, respectively D2 and D3, were each respectively formed by three metal-oxide films. The first metal oxide was a zinc oxide obtained using a ceramic cathode made of zinc oxide doped with 2 wt % aluminium and deposited in a slightly oxidizing atmosphere in order to obtain a 20 nm-thick layer of ZnAlO x . The second metal oxide was a mixed zinc-tin oxide formed using a cathode made of a zinc/tin alloy consisting of 52 wt % zinc and 48 wt % tin deposited in a reactive atmosphere consisting of a mixture of argon and oxygen so as to produce spinel zinc stannate Zn 2 SnO 4 . The third metal-oxide film of each of the two coatings D2 and D3 was a 20 nm-thick ZnO film obtained in the same way as the ZnO film of the first dielectric coating described above. The thickness of the mixed zinc-tin oxide film of each of these two coatings D2 and D3 was the complement of the thickness of the first and third metal-oxide films of each of these two coatings, so as to achieve the geometric thickness, for the second and third dielectric coatings D2 and D3, indicated in Table 1 below.
The fourth dielectric coating D4 was formed by two metal-oxide films. The first metal oxide was a zinc oxide obtained using a ceramic cathode made of zinc oxide doped with 2 wt % aluminium and deposited in a slightly oxidizing atmosphere in order to obtain a 13 nm-thick layer of ZnAlO x . The second metal oxide was a mixed zinc-tin oxide deposited in a reactive atmosphere, consisting of a mixture of argon and oxygen, using a cathode made of a zinc/tin alloy consisting of 52 wt % zinc and 48 wt % tin so as to produce spinel zinc stannate Zn 2 SnO 4 . The thickness of this second mixed zinc-tin oxide film was the complement of the thickness of the first ZnAlO x film so as to achieve the geometric thickness of the fourth dielectric coating D4 indicated in Table 1 below. Optionally, a 2 nm-thick final protective TiO 2 film may be deposited on this fourth dielectric coating, the final protective TiO 2 film being obtained using a titanium cathode in an oxidizing atmosphere consisting of a mixture of argon and oxygen. In this case, the optical thickness of this thin film must be taken into account when calculating the overall optical thickness of the fourth dielectric coating.
In Table 1, all the thicknesses indicated are geometric (physical) thicknesses. To obtain the optical thickness, all that is required is to multiply the indicated thickness by the refractive index of the material used. The values of the various thickness ratios for the dielectric coatings and functional films discussed above are also given. These ratios were calculated without taking the thickness of the sacrificial protective metal films into account, each of these films being 1.4 nm of Ti.
The coated glass sheet was then assembled, with another clear glass sheet, which was 4 mm thick, into a double glazing unit, the coating being placed on the same side as the internal cavity of the double glazing unit. The cavity separating the two sheets was 15 mm across and 90% of the air contained therein was replaced with argon. The optical and thermal properties indicated in Table 2 were obtained by observing the double glazing unit from the glass side of the coated substrate, the stack being placed in position 2, i.e. the glass side of glass sheet coated with the stack was closest to the observer, then the clear film-free glass sheet. In the present invention, the following conventions were used for the measured or calculated values. The light transmission (T L ) and the light reflection (R L ) were measured under illuminant D65/2° observer. As regards the tint in reflection, and the tint in transmission, CIELAB 1976 (L*a*b*) values were measured under illuminant D65/10° observer. The solar factor (SF or g) was calculated according to standard EN410.
In Table 2, selectivity (S) and Deltacol (DC) values have also been shown, and values for the variations in a* and b* in reflection, on the substrate side, when the viewing angle changes from 0 to 55°, called respectively “Shift a*” and “Shift b*”. “DC (R G )” indicates that the variation index (Deltacol) was obtained in reflection on the substrate side, whereas “DC (R F )” indicates that the variation index (Deltacol) was obtained on the stack side. For the tint values, “T L ” indicates that the value was measured in transmission, “R F ” indicates that the value was measured in reflection on the stack (film) side, and “R G ” indicates that the value was measured in reflection on the substrate (glass) side. The refractive index n(550), at a wavelength of 550 nm, for the dielectric materials zinc stannate, ZnO and ZnAlO x was 2.03.
It will be noted that the tints in reflection obtained are pleasant and correspond to market demand. The amount of reflection from the substrate side is not too low, thereby avoiding either a “black hole” or mirror effect. The angular variations in tint are small and completely acceptable, and the manufacturing stability is particularly good.
Examples 11-13 are temperable stacks. The thickness of the three films, made of sacrificial metal, protecting the silver films, has been increased to 2.6 nm. In this case, an optional 4 nm-thick final protective TiN film may be deposited, which protective film is converted into TiO 2 after heat treatment. If this optional film is used, the optical role of this final protective film is taken into account in the final product by incorporating its optical thickness, calculated as indicated above, into the total thickness of the last dielectric coating. The properties given in Table 2 are the properties of the resulting double glazing unit, the stack having been tempered (heated at 650° C. for 8 mins, followed by abrupt cooling with cold blow air).
As a variant, one of the following sequences of films may be used for D1, D2 and/or D3: TiO 2 /ZnO:Al or TZO/TiO 2 /ZnO or SnO 2 /ZnO/SnO 2 /ZnO or ZnO:Al/ZnSnO 4 /ZnO; for D1, one of the following sequences may be used: Si 3 N 4 /ZnO or AlN/ZnO; and for D4, one of the following sequences may be used: ZnO/SnO 2 or ZnO/TZO or ZnO:Al/ZnSnO 4 or ZnO/SnO 2 /Si 3 N 4 or ZnO/SnO 2 /AlN, optionally with an external protective film. In each case, the geometric thicknesses of the various constituents is suitably chosen, depending on their refractive index, to obtain the optical thickness of the dielectric coating corresponding to the geometric thickness indicated in Table 1 multiplied by the index 2.03. The refractive index n(550), at a wavelength of 550 nm, of the dielectric materials used are the following: for TiO 2 , n(550)=2.5; for Si 3 N 4 , n(550)=2.04; for Al 2 O 3 , n(550)=1.8; for AlN, n(550)=1.9; and for TZO, n(550)=2.26. The optical thickness must be calculated using the virtual refractive index calculated using the formula given above. The same properties were obtained.
As a variant, the protective films deposited directly on the silver films IR1, IR2 and/or IR3 may be thin (2 nm-thick), optionally aluminium-doped, TiO x or ZnO x films deposited, in an atmosphere containing an oxidizing gas or a gas that can generate oxygen such as CO 2 , using ceramic cathodes respectively made of, optionally doped, titanium or zinc oxide. When the three protective films are formed in this way from TiO x deposited using a ceramic cathode, the increase in light transmission T L may be as much as 6 to 8% for a monolithic sheet, relative to a protective film formed by sacrificial Ti metal oxidized by the process used to deposit the following dielectric coating, which process is carried out in an oxidizing atmosphere. When the three protective films are formed in this way from ZnO:Al (2 wt % aluminium) deposited using a ceramic cathode, the increase in light transmission T L is 3% for a monolithic sheet, relative to a protective film formed by sacrificial Ti metal oxidized by the process used to deposit the following dielectric coating, which process is carried out in an oxidizing atmosphere.
According to yet other variants, it is possible to replace, in the transparent dielectric coating D4, the sequence of metal oxides described above by the sequence ZnO:Al/TiO 2 or TZO, by the sequence ZnO:Al/SnO 2 /TiO 2 or TZO, or even by the sequence ZnO:Al/ZnSnO 4 /TZO.
Comparative Examples 1 and 2
Comparative Examples 1 (C1) and 2 (C2), shown in Tables 1 and 2, relate to stacks not covered by the invention because the combination of ratios of dielectric-coating thickness required by the invention has not been respected. As regards their structure, they were however produced in the same way as the examples according to the invention, Example C1 having the same structure as the non-temperable stacks and Example C2 having the same structure as the temperable stacks. The various thicknesses are given in Table 1, in the same way as for the examples according to the invention.
It will especially be noted that, for Example C1, the selectivity is clearly lower than for the examples according to the invention. The invention allows the selectivity to be optimized while preserving a pleasing appearance and a very good tint stability.
Comparative Example C2 is inspired by the teaching of document EP 645352, mentioned above. A high selectivity is obtained and a pleasing appearance, but at the expense of the stability of the tint during mass production: the value DC(R G ) is more than 20% greater than the values obtained according to the invention.
TABLE 1
D1
IR1
D2
IR2
D3
IR3
D4
D1/
D3/
D3/
IR3/
D2/
Ex
(Å)
(Å)
(Å)
(Å)
(Å)
(Å)
(Å)
D4
D2
D4
IR2
D1
1
403
118
791
120
504
125
223
1.81
0.64
2.26
1.04
1.96
2
262
114
762
125
556
136
246
1.07
0.73
2.26
1.09
2.91
3
298
122
803
128
539
132
252
1.18
0.67
2.14
1.03
2.69
4
359
120
773
124
553
139
250
1.44
0.72
2.21
1.12
2.15
5
258
112
751
133
637
153
299
0.86
0.85
2.13
1.15
2.91
6
339
123
768
136
665
156
310
1.09
0.87
2.15
1.15
2.27
7
253
86
599
127
782
191
356
0.71
1.31
2.20
1.50
2.37
8
297
91
609
126
794
193
353
0.84
1.30
2.25
1.53
2.05
9
365
110
686
139
794
186
374
0.98
1.16
2.12
1.34
1.88
10
245
93
580
136
805
177
368
0.67
1.39
2.19
1.30
2.37
11
309
106
608
140
799
189
315
0.98
1.31
2.54
1.35
1.97
12
295
128
794
137
583
146
235
1.26
0.73
2.48
1.07
2.69
13
425
131
782
140
656
162
280
1.52
0.84
2.34
1.16
1.84
C1
364
104
811
122
528
150
322
1.13
0.65
1.64
1.23
2.23
C2
300
115
726
142
693
151
296
1.01
0.95
2.34
1.06
2.42
TABLE 2
g
T L
a*
b*
L*
a*
b*
Shift
Shift
DC
DC
Ex
S
%
%
T L
T L
R G
R G
R G
a*
b*
(R G )
(R F )
1
1.98
29.7
58.8
−6.6
0.9
43.4
−0.9
−5.7
−0.5
3.4
1.8
2.3
2
1.97
29.6
58.3
−6.0
0.2
44.1
−3.7
−5.7
−0.2
4.1
1.9
2.7
3
1.98
29.0
57.4
−5.6
1.9
46.7
−4.7
−8.4
−1.6
4.3
1.8
2.5
4
2.00
29.3
58.7
−6.5
0.0
43.0
−2.4
−4.5
0.2
3.6
2.1
2.7
5
2.00
30.1
60.2
−6.1
−0.1
41.5
−3.4
−4.8
0.8
4.4
1.9
2.3
6
2.01
30.5
61.2
−5.9
0.0
40.2
−3.0
−3.9
−1.3
4.8
1.7
2.4
7
2.06
29.8
61.4
−6.2
2.9
40.5
−2.6
−6.8
−0.9
2.4
1.6
5.9
8
2.04
29.8
60.8
−5.4
3.4
41.9
−4.2
−7.4
−1.8
2.3
1.7
5.8
9
2.06
30.0
61.9
−5.4
1.5
40.0
−3.1
−4.0
−3.1
3.4
1.9
3.0
10
2.06
29.7
61.3
−5.8
3.2
41.7
−1.1
−5.6
−2.5
2.1
2.0
4.0
11
2.09
32.1
67.0
−4.3
4.1
45.3
−3.5
−6.7
−2.9
3.5
1.6
2.4
12
2.02
32.0
64.5
−4.5
3.9
48.0
−4.0
−6.8
−0.8
5.8
2.0
2.5
13
2.06
32.9
67.8
−4.5
2.5
43.2
−3.9
−3.5
−0.4
6.5
2.0
2.2
C1
1.94
29.2
56.6
−6.4
1.7
49.0
−2.7
−4.1
0.4
3.0
1.8
1.5
C2
2.03
34.9
70.9
−4.6
2.1
38.9
−1.6
−3.1
1.9
3.9
2.5
0.9 | The present invention relates to a substrate bearing a solar-control multilayer stack, and to a multiple glazing unit and to a laminated glazing unit incorporating at least one such substrate bearing a solar-control stack.
The multilayer stack comprises three functional films, each film, starting from the substrate, being thicker than the preceding one, and four transparent dielectric coatings. The ratio of the optical thickness of the third dielectric coating, to the optical thickness of the final dielectric coating, lies between 2 and 3.2, and the ratio of the optical thickness of the third dielectric coating, to the optical thickness of the second dielectric coating, is either between 0.6 and 0.91 or between 1.15 and 1.7.
The invention is applicable, in particular, to production of high-selectivity solar-control glazing units. | 2 |
FIELD OF THE INVENTION
The present invention relates to drip irrigation and more particularly to drip irrigation pipes which are biodegradable in situ.
BACKGROUND OF THE INVENTION
The following patent publications are believed to represent the current state of the art:
U.S. Pat. No. 4,474,330; U.S. Patent Publications 2008/0191464 and 2008/0072480.
SUMMARY OF THE INVENTION
The present invention seeks to provide drip irrigation pipes having desired biodegradable characteristics.
There is thus provided in accordance with a preferred embodiment of the present invention a delayed degradability drip irrigation pipe including a water conduit at a water conduit pressure and a plurality of drip irrigation outlets, each communicating with the water conduit and providing a water output at a pressure below the water conduit pressure, at least the water conduit being formed at least partially of a degradable material and also including a degradability delayer which provides a desired delay prior to failure of the water conduit but permits eventual degradation of the degradable material under predetermined conditions.
In accordance with a preferred embodiment of the present invention, the degradable material includes biodegradable material.
Preferably, the degradability delayer includes a bacterial growth delayer.
In accordance with a preferred embodiment of the present invention, the degradability delayer includes a generally non-biodegradable material which is mixed with the biodegradable material.
In accordance with a preferred embodiment of the present invention, the degradability delayer is mixed with the biodegradable material.
Preferably, the degradability delayer is formed as a co-extruded layer alongside the biodegradable material. Additionally, the degradability delayer is formed as a co-extruded inner layer of the drip irrigation pipe. Alternatively or additionally, the degradability delayer is formed as a co-extruded outer layer of the drip irrigation pipe.
In accordance with a preferred embodiment of the present invention the degradability delayer is formed as strips along the length of the drip irrigation pipe.
In accordance with a preferred embodiment of the present invention the water conduit includes at least one first layer formed of a biodegradable material, the biodegradable material being mixed with a biodegradability delayer and at least one second layer formed of a non-biodegradable, UV degradable material. Additionally, the at least one second layer also includes an oxo-biodegradable material.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:
FIG. 1 is a simplified illustration of part of a delayed degradability drip irrigation pipe constructed and operative in accordance with a preferred embodiment of the present invention;
FIG. 2 is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe, constructed and operative in accordance with a preferred embodiment of the present invention, illustrated in FIG. 1 ;
FIG. 3 is a simplified illustration of part of a delayed degradability drip irrigation pipe constructed and operative in accordance with another preferred embodiment of the present invention;
FIG. 4 is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe, constructed and operative in accordance with another preferred embodiment of the present invention, illustrated in FIG. 3 ;
FIG. 5 is a simplified illustration of part of a delayed degradability drip irrigation pipe constructed and operative in accordance with a further preferred embodiment of the present invention;
FIG. 6 is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe, constructed and operative in accordance with a further preferred embodiment of the present invention, illustrated in FIG. 5 ;
FIG. 7 is a simplified illustration of part of a delayed degradability drip irrigation pipe constructed and operative in accordance with yet another preferred embodiment of the present invention;
FIG. 8 is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe, constructed and operative in accordance with yet another preferred embodiment of the present invention, illustrated in FIG. 7 ;
FIG. 9 is a simplified illustration of part of a delayed degradability drip irrigation pipe constructed and operative in accordance with still another preferred embodiment of the present invention;
FIG. 10 is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe, constructed and operative in accordance with yet another preferred embodiment of the present invention, illustrated in FIG. 9 ;
FIG. 11 is a simplified illustration of part of a delayed degradability drip irrigation pipe constructed and operative in accordance with still a further another preferred embodiment of the present invention; and
FIG. 12 is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe, constructed and operative in accordance with yet another preferred embodiment of the present invention, illustrated in FIG. 11 .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Reference is now made to FIG. 1 , which is a simplified illustration of part of a delayed degradability drip irrigation pipe, constructed and operative in accordance with a preferred embodiment of the present invention, and to FIG. 2 , which is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe constructed and operative in accordance with the preferred embodiment of the present invention illustrated in FIG. 1 .
FIG. 1 illustrates part of a delayed degradability drip irrigation pipe 100 which includes discrete emitter units 102 distributed along the length thereof in communication with the interior thereof. It is appreciated that the present invention is not limited in its applicability to this type of drip irrigation pipe and also applies to other types of drip irrigation pipes wherein the emitters are fully or partially defined by the pipe. The present invention applies to drip irrigation pipes which are formed by extrusion and equally to drip irrigation pipes that are formed by welding of elongate sheets.
The term “biodegradable” is used throughout to refer to degradation as the result of biological activity. When applied to irrigation pipes, it is not limited to pipes which do not leave any residue whatsoever in the ground.
The irrigation pipe 100 is preferably formed of a biodegradable plastic material, such as PBAT (polybutylene adipate/teraphthalate), PTMAT (polymethylene adipate/teraphthalate), naturally produced polyester, such as PHA polyesters (polyhydroxyalkanoates), PHBH polyesters (poly-hydroxybutyrate-co-polyhydroxy hexanoates) and PLA polyesters (polylactic acid), which is biodegradable by bacterial and/or fungal action.
In accordance with a preferred embodiment of the present invention delayed degradability functionality is provided by the addition of an active anti-bacterial and anti-fungal agent which demonstrates activity against a wide range of bacteria, mold and yeast, such as CIBA® IRGAGUARD® B-1000, B-5000 or B-7000, HYGATE® 4000 or 9000 and ALPHASAN®.
Preferably, the active anti-bacterial and anti-fungal agent is mixed with the biodegradable plastic material prior to formation of the pipe, for example, prior to extrusion of the pipe or of a sheet from which the pipe is formed. Alternatively, the active anti-bacterial and anti-fungal agent is co-extruded onto one or more surface of the pipe or sheet or coated thereon.
As seen in FIG. 1 , the active anti-bacterial and anti-fungal agent may appear throughout the thickness of the pipe 100 .
Turning to FIG. 2 , degradable plastic drip irrigation pipes 100 , which include an active anti-bacterial and anti-fungal agent, are shown alongside biodegradable plastic drip irrigation pipes 110 , which do not include an active anti-bacterial and anti-fungal agent, at the same point in time.
It is seen that at a given point in time, typically six months following installation, biodegradable plastic drip irrigation pipes 110 , which do not include an active anti-bacterial and anti-fungal agent, are in the process of biodegradation, typically under bacterial and fungal action. In contrast, in accordance with a preferred embodiment of the present invention, delayed degradability drip irrigation pipes 100 , constructed and operative in accordance with a preferred embodiment of the present invention, include active anti-bacterial and anti-fungal agents, thereby delaying biodegradation under bacterial and fungal action, for a time duration, until such agents are no longer released or they become ineffective.
Reference is now made to FIG. 3 , which is a simplified illustration of part of a delayed degradability drip irrigation pipe, constructed and operative in accordance with another preferred embodiment of the present invention, and to FIG. 4 , which is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe constructed and operative in accordance with the preferred embodiment of the present invention illustrated in FIG. 3 .
FIG. 3 illustrates part of a delayed degradability drip irrigation pipe 200 which includes discrete emitter units (not shown) distributed along the length thereof in communication with the interior thereof. It is appreciated that the present invention is not limited in its applicability to this type of drip irrigation pipe and also applies to other types of drip irrigation pipes wherein the emitters are fully or partially defined by the pipe. The present invention applies to drip irrigation pipes which are formed by extrusion and equally to drip irrigation pipes that are formed by welding of elongate sheets.
The irrigation pipe 200 is preferably formed of a biodegradable plastic material, such as PBAT (polybutylene adipate/teraphthalate), PTMAT (polymethylene adipate/teraphthalate), naturally produced polyester, such as PHA polyesters (polyhydroxyalkanoates), PHBH polyesters (poly-hydroxybutyrate-co-polyhydroxy hexanoates) and PLA polyesters (polylactic acid), which is biodegradable by bacterial and/or fungal action.
In accordance with a preferred embodiment of the present invention, delayed degradability functionality is provided by provision of an active anti-bacterial and anti-fungal agent, which demonstrates activity against a wide range of bacteria, mold and yeast, such as CIBA® IRGAGUARD® B-1000, B-5000 or B-7000.
Preferably, the active anti-bacterial and anti-fungal agent is coextruded with the biodegradable plastic material during formation of the pipe or of a sheet from which the pipe is formed. Alternatively, the active anti-bacterial and anti-fungal agent is coated onto one or more surface of the pipe or sheet.
As seen in FIG. 3 , the active anti-bacterial and anti-fungal agent may appear as strips 204 along the length of the pipe 200 .
Turning to FIG. 4 , biodegradable plastic drip irrigation pipes 200 , which include an active anti-bacterial and anti-fungal agent, are shown alongside biodegradable plastic drip irrigation pipes 210 , which do not include an active anti-bacterial and anti-fungal agent, at the same point in time.
It is seen that at a given point in time, typically six months following installation, biodegradable plastic drip irrigation pipes 210 , which do not include an active anti-bacterial and anti-fungal agent, are in the process of biodegradation, typically under bacterial and fungal action. In contrast, in accordance with a preferred embodiment of the present invention, delayed degradability drip irrigation pipes 200 , constructed and operative in accordance with a preferred embodiment of the present invention, include active anti-bacterial and anti-fungal agents, thereby delaying biodegradation under bacterial and fungal action, for a time duration, until either such agents are no longer released or they become ineffective.
Reference is now made to FIG. 5 , which is a simplified illustration of part of a delayed degradability drip irrigation pipe, constructed and operative in accordance with yet another preferred embodiment of the present invention, and to FIG. 6 , which is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe constructed and operative in accordance with the embodiment of the present invention illustrated in FIG. 5 .
FIG. 5 illustrates part of a delayed degradability drip irrigation pipe 300 which includes discrete emitter units (not shown) distributed along the length thereof in communication with the interior thereof. It is appreciated that the present invention is not limited in its applicability to this type of drip irrigation pipe and also applies to other types of drip irrigation pipes wherein the emitters are fully or partially defined by the pipe. The present invention applies to drip irrigation pipes which are formed by extrusion and equally to drip irrigation pipes that are formed by welding of elongate sheets.
The irrigation pipe 300 is preferably formed of a biodegradable plastic material, such as PBAT (polybutylene adipate/teraphthalate), PTMAT (polymethylene adipate/teraphthalate), naturally produced polyester, such as PHA polyesters (polyhydroxyalkanoates), PHBH polyesters (poly-hydroxybutyrate-co-polyhydroxy hexanoates) and PLA polyesters (polylactic acid), which is biodegradable by bacterial and/or fungal action.
In accordance with a preferred embodiment of the present invention, delayed degradability functionality is provided by the addition of a generally non-biodegradable material, such as polyethylene, to the biodegradable plastic material.
Additionally, in accordance with a preferred embodiment of the present invention, delayed degradability functionality may be enhanced by the addition of an active anti-bacterial and anti-fungal agent which demonstrates activity against a wide range of bacteria, mold and yeast, such as CIBA® IRGAGUARD® B-1000, B-5000 or B-7000, HYGATE® 4000 or 9000 and ALPHASAN®. Preferably, the active anti-bacterial and anti-fungal agent is mixed with the biodegradable plastic material prior to formation of the pipe, for example, prior to extrusion of the pipe or of a sheet from which the pipe is formed.
Preferably, the generally non-biodegradable material is mixed with the biodegradable plastic material prior to formation of the pipe, for example, prior to extrusion of the pipe or of a sheet from which the pipe is formed. The resulting pipe or sheet includes relatively long linked plastic molecules which define a net or screen type structure 302 , which resists and delays degradation, such as failure due to bursting of the drip irrigation pipe 300 , notwithstanding early stage biodegradation of the biodegradable plastic material thereof.
As seen in FIG. 5 , the generally non-biodegradable material preferably is distributed generally throughout the thickness of the pipe 300 .
Turning to FIG. 6 , biodegradable plastic drip irrigation pipes 300 , which include an internal net or screen type structure 302 formed of a generally non-biodegradable material, are shown alongside biodegradable plastic drip irrigation pipes 310 , which do not include an internal net or screen type structure formed of a generally non-biodegradable material, at the same point in time.
It is seen that at a given point in time, typically six months following installation, biodegradable plastic drip irrigation pipes 310 , which do not include an internal net or screen type structure formed of a generally non-biodegradable material, are in the process of biodegradation, typically under bacterial and fungal action. In contrast, in accordance with a preferred embodiment of the present invention, delayed degradability drip irrigation pipes 300 , constructed and operative in accordance with a preferred embodiment of the present invention, are mechanically strengthened against bursting by net or screen type structure 302 , thereby delaying degradation under bacterial and fungal action for a desired time duration.
Reference is now made to FIG. 7 , which is a simplified illustration of part of a delayed degradability drip irrigation pipe, constructed and operative in accordance with still another preferred embodiment of the present invention, and to FIG. 8 , which is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe constructed and operative in accordance with the preferred embodiment of the present invention illustrated in FIG. 7 .
FIG. 7 illustrates part of a delayed degradability drip irrigation pipe 400 which includes discrete emitter units 402 distributed along the length thereof in communication with the interior thereof. It is appreciated that the present invention is not limited in its applicability to this type of drip irrigation pipe and also applies to other types of drip irrigation pipes wherein the emitters are fully or partially defined by the pipe. The present invention applies to drip irrigation pipes which are formed by extrusion and equally to drip irrigation pipes that are formed by welding of elongate sheets.
The irrigation pipe 400 is preferably formed of a biodegradable plastic material, such as PBAT (polybutylene adipate/teraphthalate), PTMAT (polymethylene adipate/teraphthalate), naturally produced polyester such as PHA polyesters (polyhydroxyalkanoates), PHBH polyesters (poly-hydroxybutyrate-co-polyhydroxy hexanoates) and PLA polyesters (polylactic acid), which is biodegradable by bacterial and/or fungal action.
In accordance with a preferred embodiment of the present invention, delayed degradability functionality is provided by the addition of an active anti-bacterial and anti-fungal agent, which demonstrates activity against a wide range of bacteria, mold and yeast, such as CIBA® IRGAGUARD® B-1000, B-5000 or B-7000, HYGATE® 4000 or 9000 and ALPHASAN®, to at least one of, and preferably all of, an outer coextruded biodegradable plastic layer 404 , an innermost coextruded biodegradable plastic layer 405 and a middle biodegradable plastic layer 406 of pipe 400 .
Preferably, the active anti-bacterial and anti-fungal agent is mixed with the biodegradable plastic material used to form layer 404 , layer 405 and/or layer 406 , prior to coextrusion of the pipe or of a sheet from which the pipe is formed.
As seen in FIG. 7 , the active anti-bacterial and anti-fungal agent may appear throughout the thickness of the outer layer 404 , innermost layer 405 and/or middle layer 406 of pipe 400 . It is appreciated that the active anti-bacterial and anti-fungal agents included in outer layer 404 , innermost layer 405 and middle layer 406 may be the same for each layer or may be different for each layer to provide different time delays for the delayed degradability functionality of delayed degradability drip irrigation pipe 400 .
Turning to FIG. 8 , biodegradable plastic drip irrigation pipes 400 , in which at least one of outer layer 404 , innermost layer 405 and/or middle layer 406 include an active anti-bacterial and anti-fungal agent, are shown alongside biodegradable plastic drip irrigation pipes 410 , which do not include an active anti-bacterial and anti-fungal agent, at the same point in time.
It is seen that at a given point in time, typically six months following installation, biodegradable plastic drip irrigation pipes 410 , which do not include at least one layer including an active anti-bacterial and anti-fungal agent, are in the process of biodegradation, typically under bacterial and fungal action. In contrast, in accordance with a preferred embodiment of the present invention, delayed degradability drip irrigation pipes 400 , constructed and operative in accordance with the preferred embodiment of the present invention of FIG. 7 include active anti-bacterial and anti-fungal agents, thereby delaying biodegradation under bacterial and fungal action for a time duration until either such agents are no longer released or they become ineffective.
It is appreciated that, although in the illustrated embodiment shown in FIG. 7 , pipes 400 include three layers 404 , 405 and 406 , in accordance with the present invention pipes 400 may include any number of layers, including two or more layers, of which at least one layer includes active anti-bacterial and anti-fungal agents. In a most preferred embodiment of the present invention, at least the outermost layer of pipes 400 includes active anti-bacterial and anti-fungal agents.
Reference is now made to FIG. 9 , which is a simplified illustration of part of a delayed degradability drip irrigation pipe, constructed and operative in accordance with still another preferred embodiment of the present invention, and to FIG. 10 , which is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe constructed and operative in accordance with the preferred embodiment of the present invention illustrated in FIG. 9 .
FIG. 9 illustrates part of a delayed degradability drip irrigation pipe 500 which includes discrete emitter units 502 distributed along the length thereof in communication with the interior thereof. It is appreciated that the present invention is not limited in its applicability to this type of drip irrigation pipe and also applies to other types of drip irrigation pipes wherein the emitters are fully or partially defined by the pipe. The present invention applies to drip irrigation pipes which are formed by extrusion and equally to drip irrigation pipes that are formed by welding of elongate sheets.
The irrigation pipe 500 is preferably formed of a biodegradable plastic material, such as PBAT (polybutylene adipate/teraphthalate), PTMAT (polymethylene adipate/teraphthalate), naturally produced polyester such as PHA polyesters (polyhydroxyalkanoates), PHBH polyesters (poly-hydroxybutyrate-co-polyhydroxy hexanoates) and PLA polyesters (polylactic acid), which is biodegradable by bacterial and/or fungal action.
In accordance with a preferred embodiment of the present invention, delayed degradability functionality is provided by the addition of at least one of an outer coextruded biodegradable plastic layer 504 and an innermost coextruded biodegradable plastic layer 505 , containing an active anti-bacterial and anti-fungal agent which demonstrates activity against a wide range of bacteria, mold and yeast, such as CIBA® IRGAGUARD® B-1000, B-5000 or B-7000, HYGATE® 4000 or 9000 and ALPHASAN®.
Preferably, the active anti-bacterial and anti-fungal agent is mixed with the biodegradable plastic material used to form layer 504 and/or layer 505 , prior to coextrusion of the pipe or of a sheet from which the pipe is formed.
It is appreciated that the active anti-bacterial and anti-fungal agent may appear throughout the thickness of the outer layer 504 and/or innermost layer 505 of pipe 500 .
Turning to FIG. 10 , biodegradable plastic drip irrigation pipes 500 , which include a coextruded outer layer 504 and/or inner layer 505 , including an active anti-bacterial and anti-fungal agent, are shown alongside biodegradable plastic drip irrigation pipes 510 , which do not include an active anti-bacterial and anti-fungal agent, at the same point in time.
It is seen that at a given point in time, typically six months following installation, biodegradable plastic drip irrigation pipes 510 , which do not include a coextruded outer layer including an active anti-bacterial and anti-fungal agent, are in the process of biodegradation, typically under bacterial and fungal action. In contrast, in accordance with a preferred embodiment of the present invention, delayed degradability drip irrigation pipes 500 , constructed and operative in accordance with the preferred embodiment of the present invention of FIG. 9 include active anti-bacterial and anti-fungal agents, thereby delaying biodegradation under bacterial and fungal action for a time duration until either such agents are no longer released or they become ineffective.
Reference is now made to FIG. 11 , which is a simplified illustration of part of a delayed degradability drip irrigation pipe, constructed and operative in accordance with still a further preferred embodiment of the present invention, and to FIG. 12 , which is a simplified comparative illustration of the relative degradability characteristics of a biodegradable drip irrigation pipe and of the delayed degradability drip irrigation pipe constructed and operative in accordance with the preferred embodiment of the present invention illustrated in FIG. 11 .
FIG. 11 illustrates part of a delayed degradability drip irrigation pipe 600 which includes discrete emitter units 602 distributed along the length thereof in communication with the interior thereof. It is appreciated that the present invention is not limited in its applicability to this type of drip irrigation pipe and also applies to other types of drip irrigation pipes wherein the emitters are fully or partially defined by the pipe. The present invention applies to drip irrigation pipes which are formed by extrusion and equally to drip irrigation pipes that are formed by welding of elongate sheets.
The irrigation pipe 600 is preferably formed with an outer layer 604 of a biodegradable plastic material, such as PBAT (polybutylene adipate/teraphthalate), PTMAT (polymethylene adipate/teraphthalate), naturally produced polyester such as PHA polyesters (polyhydroxyalkanoates), PHBH polyesters (poly-hydroxybutyrate-co-polyhydroxy hexanoates) and PLA polyesters (polylactic acid), which is biodegradable by bacterial and/or fungal action.
In accordance with a preferred embodiment of the present invention, delayed degradability functionality is provided by the addition to the outer layer 604 of an active anti-bacterial and anti-fungal agent which demonstrates activity against a wide range of bacteria, mold and yeast, such as CIBA® IRGAGUARD® B-1000, B-5000 or B-7000, HYGATE® 4000 or 9000 and ALPHASAN®.
In accordance with a preferred embodiment of the present invention, additional delayed degradability functionality is provided by the provision of an inner layer 606 formed of a plastic material which is not-biodegradable but is degradable in response to exposure to another degradability initiator, such as UV. A suitable UV degradable plastic material is polyethylene. Layers 604 and 606 are preferably co-extruded.
Additionally, inner layer 406 may also include an oxo-biodegradable material, such as EPIcor™ 2058, commercially available from EPI Environmental Products, Inc., of Vancouver, B.C., Canada, which enhances breakdown of inner layer 606 .
Preferably, the active anti-bacterial and anti-fungal agent is mixed with the biodegradable plastic material used to form layer 604 , prior to co-extrusion of the pipe or of a sheet from which the pipe is formed.
It is appreciated that the active anti-bacterial and anti-fungal agent may appear throughout the thickness of the outer layer 604 .
Turning to FIG. 12 , biodegradable plastic drip irrigation pipes 600 , which include a coextruded outer layer 604 and inner layer 606 as described hereinabove, are shown alongside biodegradable plastic drip irrigation pipes 610 , which do not include an active anti-bacterial and anti-fungal agent, at the same point in time.
It is seen that at a given point in time, typically six months following installation, biodegradable plastic drip irrigation pipes 610 , which do not include a coextruded outer layer including an active anti-bacterial and anti-fungal agent, are in the process of biodegradation, typically under bacterial and fungal action. In contrast, in accordance with a preferred embodiment of the present invention, delayed degradability drip irrigation pipes 600 , constructed and operative in accordance with the preferred embodiment of the present invention of FIG. 11 , remain intact and functional for a predetermined, desired duration.
It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described hereinabove. Rather, the scope of the present invention includes combinations and subcombinations of the features described above as well as modifications and variations which would occur to persons skilled in the art upon reading the foregoing description and which are not in the prior art. | A delayed degradability drip irrigation pipe including a water conduit at a water conduit pressure and a plurality of drip irrigation outlets, each communicating with the water conduit and providing a water output at a pressure below the water conduit pressure, at least the water conduit being formed at least partially of a degradable material and also including a degradability delayer which provides a desired delay prior to failure of the water conduit but permits eventual degradation of the degradable material under predetermined conditions. | 8 |
FIELD OF THE INVENTION
[0001] This invention relates to an adjustment device, hereinafter referred to as an actuator, suitable for adjusting the operating position of another device, such as a lumbar support, either directly or by means of a Bowden cable system.
BACKGROUND OF THE INVENTION
[0002] Bowden cable systems are used in a wide variety of applications. One application is in adjusting a lumbar support built into a seat, such as a seat of an automotive vehicle. The Bowden cable system has a wire cable extending through a sleeve. The sleeve usually is held stationary at each end, enabling relative longitudinal movement between it and the cable. An actuator coupled to one end of the cable is able to move the cable reversibly, longitudinally through the sleeve, to enable reversible application of a force to a device, such as a lumbar support, coupled to the other end of the cable. The Bowden cable system is relatively inexpensive. Also, of importance in automotive applications, it is able to operate quietly, while its flexibility enables its use in situations of limited available space.
[0003] A number of different forms of actuator have been proposed for use with a Bowden cable system. Examples are shown by U.S. Pat. No. 5,638,722 to Klingler; U.S. Pat. No. 6,053,064 to Gowing et al; and U.S. Pat. No. 6,520,580 to Hong. In each case, the actuator/Bowden cable system combination is disclosed in relation to a lumbar support for an automotive vehicle seat, a principal application for the actuator of the present invention.
[0004] The actuator disclosed in U.S. Pat. No. 5,638,722 to Klingler has a threaded spindle which is guided in axial movement in a tubular housing, but with torsional strength on a guide. One end portion of the spindle projects from the housing and comprises a threaded ring with which a nut of an adjustment handle is in threaded engagement. At their ends remote from the handle, each of the spindle and housing respectively has a radial opening, an axial bore and a radial slot connecting the opening and bore. With the spindle moved axially to bring the radial openings into alignment, a nipple on the end of a cable of a Bowden system can be inserted into the spindle. As the slots are in a common plane, the cable then can be secured by moving it through the slots, into the aligned bores to retain the nipple within the spindle. At the remote end, the housing has an extension in which an end of the sleeve of the cable system is received and locked. The cable is able to be reversibly moved longitudinally with the spindle, by rotating the handle and its nut.
[0005] In U.S. Pat. No. 6,053,064, Gowing et al discloses an actuator which, in terms of the disclosure of Klingler as detailed above, is essentially the same. However, Gowing et al proposes a separate barrel, fixedly coupled to the end of the housing remote from the handle, for fixing the Bowden system sleeve. This necessitates the cable being passed through a bore in the barrel before its nipple is fitted, while the barrel is simply abutted by the sleeve. The arrangement of Gowing et al differs further in proposing a thread stop coupled with its screw or spindle to prevent the screw from being moved completely out of the nut. Additionally, the nut has a tubular extension which projects away from the screw, with the tubular extension coupled to and rotatable with a handle by a spline coupling therebetween provided by inter-fitting key elements and slots.
[0006] As with the actuator of Klingler, the actuator of Gowing et al has a threaded spindle or screw guided for axial movement, but with torsional strength on a guide. That is, in each case, the screw or spindle is constrained against rotation. In Gowing et al, this is shown by diametrically opposite feet or lugs on the spindle or screw locating in axially extending grooves in the housing. This of course prevents twisting of the cable, as is highly desirable, particularly as twisting in one direction would act to untwist the strands of which the cable is made.
[0007] U.S. Pat. No. 6,520,580 to Hong discloses an actuator which essentially is the same as that of Klingler. As in Gowing et al, the express disclosure is of a nut and handle arrangement with a splined coupling therebetween. The arrangement of Hong proposes a coil spring within the housing and through which the cable of the Bowden system extends to the spindle or screw. As with the barrel of Gowing et al, this complicates coupling and uncoupling of the actuator and cable system.
[0008] The present invention seeks to provide an improved actuator which, while retaining some of the benefits of the prior art discussed above, also enables additional benefits to be obtained.
SUMMARY OF THE INVENTION
[0009] In accordance with the present invention, there is provided an actuator connectable to and for adjusting an adjustable device, wherein the actuator comprises: a housing having a longitudinal passage extending between a first end and a second end of the housing and defining an opening at or adjacent to the second end;
a spindle supported in the housing and movable longitudinally in the housing passage, the spindle having two oppositely handed, longitudinally spaced threaded portions of which a first threaded portion is nearer to the first end and a second threaded portion is nearer to the second end; a first threaded nut fixed relative to the housing and threadedly engaged with the first threaded portion of the spindle; a handle rotatably mounted at the first end of the housing, the handle being coupled to the spindle for rotating the spindle in the first nut and thereby moving the spindle longitudinally relative to the first nut and the housing; a second nut fixed against rotation relative to the housing and threadedly engaged with the second threaded portion of the spindle, whereby in response to rotation of the spindle by the handle the second nut is movable longitudinally in the housing passage relative to the spindle, in the same direction as movement of the spindle relative to the housing; and connecting means on or of the second nut and connectable, through the opening defined by the housing, to an adjustable device to be adjusted by the actuator, wherein the spindle is rotatable by the handle for adjusting the adjustable device by longitudinal movement in the same direction of the spindle relative to the housing and of the second nut relative to the spindle.
[0016] The connecting means on or of the second nut can take a variety of forms. In a first embodiment the actuator is connectable to an adjustable device by means of a Bowden cable system. That is, the actuator is indirectly connectable to the adjustable device, albeit in a manner which permits considerable freedom as to how the cable system is arranged and where the actuator is mounted relative to the adjustable device. In that first embodiment, the actuator further comprises:
an opening formed in the second nut and configured for receiving and securing an end of a cable of a Bowden cable system and thereby comprising the connecting means; and the housing at the second end having an engagement member for fixing a sleeve of the Bowden cable system;
wherein the spindle is operable for moving the cable longitudinally through the sleeve for adjusting the adjustable device to which the other end of the Bowden cable system is connected.
[0020] In a second embodiment, the actuator is connectable to an adjustable device by a direct coupling between the second nut and the adjustable device. Thus, the second nut may be coupled to the adjustable device by a projection which extends laterally of the second nut, through the opening defined by the housing, with that opening being in the form of an elongate slot extending longitudinally along the housing at the second end. Preferably there is a respective such projection and elongate slot at each of opposite sides of the second nut and housing.
[0021] In the second embodiment, the connecting means may be at least one such projection. The projection may be formed integrally with the second nut, or be connected to the nut such as by screw threaded engagement in a lateral, threaded bore defined by the second nut. Where there is a respective projection at each of opposite sides of the second nut, the projections may comprise opposite end portions of a single member such as a pin, shaft or rod which extends through a diametral lateral bore defined by the second nut. The single member may be glued or welded to the second nut, or in threaded engagement in the lateral bore. In each case, the at least one projection is adapted to be coupled to the adjustable device exteriorly of the housing, such as by a pivotal coupling between the projection and the device.
[0022] Alternatively, the at least one projection may be defined by the adjustable device, with the connecting means adapted to enable the projection to be connected to the second nut. In such alternatives, the connecting means may comprise a lateral bore defined by the second nut and in which an end of the projection is engageable, such as by screw threaded engagement or by being held captive in the bore against retraction therefrom.
[0023] The actuator of the present invention is able to use a thread pitch for each threaded portion and the respective nut which makes the actuator easier to operate, or to enable a greater range of movement for the adjustable device per revolution at a given thread pitch, or to provide a combination of these benefits. This is because the distance the adjustable device is moved is the aggregate of the longitudinal distance moved by the spindle relative to the housing, and the longitudinal distance moved by the second nut relative to the spindle. Thus, for the same given thread pitch for each threaded portion of the spindle, the distance through which the adjustable device is able to be moved is twice the distance moved by the spindle relative to the housing. Thus, there is greater scope for selection of the thread pitch for ease of operation, or to achieve a required movement of the adjustable device per revolution of the spindle, or a combination of these results. Also, while it generally is beneficial for the thread of each threaded portion of the spindle to have a common pitch, this is not necessary. That is, for each revolution of the spindle, the longitudinal distance moved by the second nut relative to the spindle may be greater or less than the longitudinal distance moved by the spindle.
[0024] The handle and spindle are rotatable in unison. The handle may be mounted to the housing and held against movement longitudinally with respect to the housing. In that case, a coupling between the handle and the spindle is to be such as to enable the spindle to adjust longitudinally relative to the handle as the spindle moves longitudinally with respect to the housing. To enable this, an end portion of the spindle at the first end of the housing preferably is movable longitudinally within a sleeve defined by the handle, with there preferably being a key and keyway or splined coupling between the handle sleeve and the spindle. However, the handle may be mounted to the spindle, rather than the housing, with the handle able to move longitudinally with the spindle, as the spindle moves longitudinally in the housing passage while being rotated by the handle.
[0025] The first nut may be a friction fit in the housing, or it may be a snap-fit so as to locate behind a slight protrusion defined in the housing. In each case, the first nut preferably is insertable into the passage of the housing from the first end of the housing. The housing may define at least one radially extending shoulder, such as of at least part-annular form, against which the first nut locates when in its required position longitudinally of the housing. The first nut may have an outer periphery which is non-circular in cross-section, such as square or hexagonal, and which is complementary to the form of the cross-section of the part of the passage along which the first nut is movable to its required position, such that the first nut is constrained against rotation. However, both the first nut and that part of the passage preferably are of circular cross-section, with the nut having at least one radial projection which is slidable in a longitudinal slot defined by the housing along that part of the passage. The first nut preferably has at least two angularly spaced radial projections, each slidable in a respective slot defined by the housing.
[0026] The second nut preferably has two longitudinally adjacent sections. The first of these sections is an internally threaded sleeve by which the second nut is engaged with the second threaded portion of the spindle. The second section of the second nut extends longitudinally beyond the spindle from the first section, towards the second end of the housing. In each embodiment, the connecting means preferably is provided in the second section of the second screw. Thus, for example, in the case of an indirect arrangement using a Bowden cable system, the opening in the second nut is formed in the second section and preferably opens laterally. Also, the second section preferably defines a radial slot extending from the lateral opening towards the second end of the housing whereby, with the nipple of the cable of the Bowden system received in the lateral opening, the cable can be adjusted so as to extend longitudinally from the second nut.
[0027] The second section of the second nut, apart from defining an opening configured for receiving and securing the end of the cable of the Bowden system, may be of solid form. However, this is not essential and, for example, a passage defined by the internally threaded sleeve of the first section of the second nut may continue through the second section. Where the configured opening opens laterally, it may extend through to the passage.
[0028] The second nut also may have an outer periphery which is non-circular in cross-section, such as square or hexagonal, and which is complementary to the form of the cross-section of the part of the passage along which the second nut is movable relative to the spindle, such that the second nut is constrained against rotation. However, both the second nut and that part of the passage preferably are of circular cross-section, with the second nut having at least one radial projection which is slidable along a longitudinal slot defined by the housing along that part of the passage. The second nut preferably has at least two angularly spaced radial projections, each slidable in a respective slot defined by the housing. The slot for a radial projection of the second nut preferably is the same radial plane as the slot for a radial projection for the first nut, although the respective slots preferably are not longitudinally in line with each other.
[0029] Adjacent to its second end, the housing of an actuator for use with a Bowden cable system also may define a side opening communicating with the passage, and a slot extending from the opening to the second end. Thus, as the cable is adjusted so as to extend longitudinally from the second nut, it also is able to be adjusted to extend through the second end of the housing. For this, it is necessary that the respective side openings and slots of the second nut and the housing be brought into longitudinal and radial alignment, as taught by the disclosure of U.S. Pat. No. 5,638,722 to Klingler. However, other arrangements are possible. For example, prior to affixing a nipple to the end of the cable of the Bowden system, the cable can be passed longitudinally through the housing, from the second end to the first end, and the nipple then affixed to the cable before the cable is secured to the second nut.
[0030] The housing may be of elongate form. It preferably is able to receive therein, from the first end, an assembly comprising the spindle with each of the first and second nuts screwed onto the respective first and second threaded portions of the spindle. Prior to installation of the assembly, the nuts may be at one or other of first and second extreme positions along the threaded portions. In the first, preferred one of those positions for installation, the assembly may be such that when installed in the housing the spindle is at its extreme position near to the first end of the housing with the first nut at the end of the first threaded section which is nearer to the second end of the housing, and with the second nut at the end of the second threaded section which is nearer to the first end of the housing. Thus, the second nut is at a minimum longitudinal spacing from the first nut. In the second position, the assembly is such that when installed in the housing, the spindle is at its extreme position nearer to the second end of the housing, with the first nut at the end of the first threaded section nearer to the first end of the housing and the second nut at the end of the second threaded section nearer to the second end of the housing, and the nuts at a maximum longitudinal spacing from each other. However, as will be appreciated, the assembly once installed, is reversibly adjustable between those extremes, with the second nut able to move relative to the spindle in the same direction as the spindle is moved relative to the housing.
[0031] The housing may be of a form such that its passage, apart from longitudinal grooves for preventing rotation of the first and second nuts, is of a substantially uniform, preferably circular, cross-section. However, as detailed later herein, a region of the spindle between the two threaded sections may have at least one lateral projection. To accommodate this, and to minimise material usage, the housing may have a form such that its passage has a larger cross-section over that part of its length from the inlet end to a furthest longitudinal position from the inlet end travelled by such projection as the spindle moves longitudinally, than its cross-section from that position to the second end.
[0032] The engagement member at the second end of the housing may be a small sub-housing adapted to receive therein a suitably shaped termination of the sleeve of the Bowden system. The sub-housing may have a part cylindrical peripheral wall which defines a lateral opening through which at least part of the termination is receivable, such as by a snap fit. Preferably such peripheral wall is provided with an inwardly extending flange or bead at its edge remote from the housing which serves to retain the termination from longitudinal disengagement from the actuator.
[0033] The spindle is of elongate form, and has three principal longitudinal sections. These include the first and second threaded sections while a third section is the part of the spindle with which the handle is coupled. The handle remains coupled to the third section as the spindle moves longitudinally. Thus if, as preferred, the spindle moves longitudinally with respect to the handle, the third section needs to be of at least comparable length to the length of the first threaded section. Assuming the same thread pitch for each of the threaded sections, each of the three sections can comprise about one third of the length of the spindle. However, the third part can be shorter if the handle is attached to the spindle for both rotational and longitudinal movement with the spindle.
[0034] The spindle is rotatable with the handle. However, in moving longitudinally relative to the first nut as it rotates, the spindle may either be movable longitudinally relative to the handle or the handle may be movable longitudinally with the spindle. Where the spindle is movable longitudinally relative to the handle, the handle preferably has a central hub in which the third section of the spindle is located and is longitudinally movable. The handle is coupled by the hub to the third section in a manner enabling relative longitudinal movement therebetween. Thus, the third section of the spindle may be of non-circular cross-section and be receivable in a passage defined by the hub which is of complementary cross-section, or the hub and third section may define longitudinally adjustable key elements and slots, or a splined coupling. Alternatively, one of the third section of the spindle and the hub may define an elongate longitudinal slot in which a pin or peg on the other of the third section and hub is located to enable the required extent of relative longitudinal movement. Where the handle and spindle are longitudinally movable together, they may be bonded together (after fitting the first nut), or permanently or releasably secured together by screw threaded engagement, lateral pins, or the like.
[0035] In addition to its coupling to the spindle, the handle may have a sleeve which fits over the first end of the housing. Where the spindle is longitudinally movable relative to the handle, the sleeve may be a snap fit onto the first end of the housing in a manner which releasably retains the handle against longitudinal movement relative to the housing. However, where the handle is longitudinally movable with the spindle, the sleeve may simply be telescopically received over the first end of the housing for relative movement therebetween.
[0036] In addition to the features detailed, the handle can take a variety of forms. It may include a transverse lever integral with the hub and sleeve. Alternatively it may be a wheel or disc co-axial with the hub and sleeve. Preferably the handle has a scalloped edge form to define a plurality of spokes extending radially outwardly around the hub and sleeve, with a respective arcuate web between each successive pair of spokes.
[0037] With the actuator adjusted so that the assembly comprising the spindle and the first and second nuts is in the first extreme position, hereinafter referred to as the “on” position, the spindle is retracted away from the second end of the housing to the first end, and the second nut is similarly retracted along the second threaded section of the spindle so as to be in its position closest to the first nut. Thus, the cable of a Bowden system secured to the second nut will have been tensioned and pulled into the housing, through the engagement member and the second end. The actuator is in the “on” position because the cable tension will have moved a device to which the other end of the cable is connected from a rest position, or from a position to which it is biased, to an active or on position. Thus, where for example the other end of the cable is connected to a lumbar support, the actuator in the “on” position holds the support in its most forwardly advanced supporting position. Conversely, with the actuator in the other extreme position, herein referred to as the “off” position, the spindle and the second nut will have moved towards the second end of the housing, releasing tension on the cable and enabling the device to return to rest or biased position.
[0038] The “on” position preferably is sharply defined, by an abutment surface at the end of the spindle near to the second end of the housing being contacted by an abutment surface defined within the sleeve section of the second nut. The abutment at the end of the spindle may be provided by an abrupt termination of the thread of the second threaded portion, rather than the usual threaded termination. The abrupt termination may extend substantially radially in a plane substantially parallel to the axis of rotation of the spindle, while the abutment surface of the second nut is similarly disposed and opposed to the thread termination when the “on” position is attained.
[0039] The spindle may have a short unthreaded part of its length between adjacent ends of the threads of the first and second threaded sections. it is at this unthreaded part that it is convenient to provide abutment means which provides a sharply defined stop with the actuator in its “off” position. For this, the spindle may have a lateral projection at the unthreaded part, with the projection having an abutment face which makes surface to surface contact with an abutment face defined by the housing when the spindle reaches the “off” position. The abutment face of the spindle is somewhat radial and leads in the direction of helical advance of the spindle as it rotates and moves longitudinally towards the second end of the housing to its longitudinal location for the “off” position. The abutment face defined by the housing is similarly disposed but oppositely facing for good surface to surface contact between the abutment faces. While the respective abutment surfaces are substantially radially disposed, it is preferred that they are inclined slightly to the radial such that the outer edge of the spindle abutment surface leads in the direction of spindle rotation to the “off” position. This inclination brings the abutment surfaces into more positive face to face engagement in the event of excessive torque being applied to the spindle, thereby minimising the risk of the spindle abutment being able to be forced radially within the housing abutment and jamming of the actuator. This risk preferably is further reduced by the spindle having a spacer which projects laterally from the unthreaded part of the spindle, at a location diametrically opposed to the abutment face of the spindle. The spacer has a lateral extent such that it bears against the housing to prevent lateral displacement of the spindle sufficient to enable the spindle abutment to pass radially within the housing abutment.
[0040] The foregoing explanation of operation of an actuator according to the first embodiment using a Bowden cable system, in terms of movement between “on” and “off” positions, is similarly applicable to an actuator of the second embodiment which is directly connectable to an adjustable device. Thus, with the connecting means connected to a location on the adjustable device, that location is caused to move with the second nut with adjustment of the actuator between the “on” and “off” positions. The nature of the adjustment of the adjustment device will vary with its form and its disposition relative to the longitudinal extent of the actuator.
BRIEF DESCRIPTION OF THE DRAWINGS
[0041] The accompanying drawings illustrate preferred embodiments of the actuator of the present invention. The detailed description of the drawings is to assist with an appreciation of the construction and function of the actuator. In the drawings:
[0042] FIG. 1 is a perspective view of a first embodiment of an actuator according to the present invention;
[0043] FIG. 2 is a partly cut-away perspective view of the actuator of FIG. 1 , but taken from the opposite side and showing the actuator in a first condition;
[0044] FIG. 3 is similar to FIG. 2 , but shows the actuator of the first embodiment in a second condition;
[0045] FIG. 4 is a full sectional view of the device of FIG. 1 , in the first condition shown in FIG. 2 ;
[0046] FIG. 5 is similar to FIG. 4 , but shows the actuator in the second condition of FIG. 3 ;
[0047] FIG. 6 is a transverse sectional view taken on line VI-VI of FIG. 5 ;
[0048] FIG. 7 is a transverse sectional view taken on line VII-VII of FIG. 5 ;
[0049] FIG. 8 is a transverse sectional view taken on line VIII-VIII of FIG. 5 ;
[0050] FIG. 9 is a transverse sectional view taken on line IX-IX of FIG. 5 ;
[0051] FIG. 10 is a transverse sectional view taken on line X-X of FIG. 5 ; and
[0052] FIG. 11 is a perspective view of a second embodiment of an actuator according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0053] With reference to FIGS. 1 to 5 , the actuator 10 shown therein has an elongate cylindrical housing 12 , of circular cross-section, which has a handle 14 at one end and receives one end of a Bowden cable system 16 at the other end. From its first end, at which handle 14 is provided, housing 12 defines a passage 13 which has a maximum diameter through to a first step 18 , an intermediate diameter from step 18 to a second step 19 , and a minimum diameter from step 19 through to the second end through which system 16 is received. Adjacent to handle 14 , housing 12 has two diametrically opposed lugs 20 by which actuator 10 is able to be mounted on a suitable support, such as a side frame of a vehicle seat. In the context of a vehicle seat, the end of system 16 remote from actuator 10 may be connected to an adjustable device to be adjusted or actuated through system 16 by actuator 10 . The device at the remote end may, for example, be a lumbar support mounted within the seat-back.
[0054] As seen most clearly in FIGS. 4 and 5 , actuator 10 includes an elongate spindle 22 within passage 13 of housing 12 . The spindle 22 has a handle engaging portion 24 at the first end of housing 12 , followed in turn by a first externally threaded portion 26 and a second externally threaded portion 28 . Of the threaded portions 26 , 28 , the first is nearer to the first end, while the second is nearer to the second end, of housing 12 . Also within housing 12 , there is a first nut 30 with which first portion 26 of spindle 22 is in threaded engagement, and a second nut 32 with which second portion 28 of spindle 22 is in threaded engagement. Preferably the thread of each of the portions 26 and 28 has substantially the same pitch.
[0055] The handle 14 has a transverse end wall 34 around the circumference of which there is a skirt 36 . The skirt 36 has angularly spaced protrusions 36 a which assist a user to grip and rotate handle 14 . Concentrically within skirt 36 , handle 14 has a sleeve 37 which is neatly received over the first end of housing 12 . Within sleeve 37 , handle 14 has a central sleeve 38 in which portion 24 of spindle 22 is received.
[0056] The handle 14 is releasably and rotatably retained on the first end of housing 12 . This is by a peripheral groove 39 defined around the internal surface of sleeve 37 engaging on a continuous or discontinuous bead 40 defined around the external surface of housing 12 . The handle 14 also is coupled to spindle 22 in a manner such that rotation of handle 14 causes rotation of spindle 22 , while allowing spindle 22 to move longitudinally in passage 13 relative to housing 12 and handle 14 . As shown most clearly in the sectional view of FIG. 6 , the portion 24 of spindle 22 has an angularly spaced array of longitudinal ribs 24 a which are slidable in a complementary angularly spaced array of longitudinal grooves 38 a defined by the inner surface of sleeve 38 . The inter-fitting ribs 24 a and grooves 38 a cause spindle 22 to rotate with handle 14 , while allowing the spindle to move longitudinally with respect to handle 14 to vary the extent to which portion 24 of spindle 22 projects into sleeve 38 .
[0057] The first nut 30 , over a first part of its axial extent as it is received into passage 13 from the first end, is a neat fit within the intermediate diameter section of passage 13 of housing 12 between steps 18 and 19 . A trailing part of its axial extent as it is so received defines a flange 30 a which is a neat sliding fit in the maximum diameter section of passage 13 up to step 18 . As seen most clearly in FIG. 7 , nut 30 has longitudinal grooves 30 b in its flange 30 a , in which longitudinal ribs 12 a of housing locate. Thus, nut 30 is secured against rotation. Also, as seen most clearly in FIG. 1 , housing 12 at each of diametrically opposite location, has a U-shape groove 12 b cut therethrough to define a resilient tab 41 . Each tab 41 is deformed inwardly into passage 13 so that, once nut 30 has been longitudinally moved into position within passage 13 , from the first end of housing 12 , the tabs 41 locate behind flange 30 a of nut 30 and hold unit 30 against a shoulder 42 defined in passage 13 at step 18 and also restrain nut 30 against unintended retraction. The situation is such that, in addition to being held against rotation, nut 30 is held against longitudinal movement. Thus, when rotated by handle 14 , spindle 22 is caused by its threaded engagement with nut 30 to move longitudinally along passage 13 in a direction determined by the direction of rotation.
[0058] The second nut 32 is threaded onto the second threaded portion 28 of spindle 22 and is a neat sliding fit in the minimum diameter section of passage 13 between step 19 and the second end. The nut 32 has two longitudinally adjacent sections, comprising an internally threaded sleeve 43 by which nut 32 is engaged on portion 28 of spindle 22 , and a section 44 located beyond the free end of portion 28 . As shown in FIG. 8 , nut 32 has a projection 32 a at each of opposed sides, with each projection located in a respective groove 12 c defined along the minimum diameter length of passage 13 . Thus, nut 32 is constrained against rotation relative to housing 12 , but is able to move longitudinally therein.
[0059] The thread of the respective portions 26 and 28 of spindle 22 are of opposite hand. That is, when spindle 22 is viewed from one end, the thread of one of portions can be seen to be clockwise, while the other is anti-clockwise. Thus, with rotation of spindle 22 by handle 14 , spindle 22 moves longitudinally along passage 13 with respect to housing 12 , while the second nut 32 moves longitudinally relative to spindle 22 and in the same direction as spindle 22 .
[0060] With rotation of handle 14 , the actuator 10 can be moved between two extreme positions. The first of those positions, shown in FIGS. 2 and 4 is herein designated as the “off” position, while the other of the positions is shown in FIGS. 3 and 5 and is designated as the “on” position. To attain the “off” position, spindle 22 is rotated so as to move longitudinally along passage 13 , relative to and towards the second end of housing 12 . Spindle 22 rotates relative to the fixed first nut 30 and, in being rotated by handle 14 , is caused by its threaded engagement with nut 30 to move longitudinally. As second nut 32 is constrained against rotation relative to housing 12 , spindle 22 rotates relative to nut 32 , while the threaded engagement between spindle 22 and nut 32 causes longitudinal movement of nut 32 relative to housing 12 and also relative to spindle 22 . As the threaded engagement between spindle 22 and nut 32 is of opposite hand to the threaded engagement between spindle 22 and nut 30 , nut 32 moves relative to housing 12 in the same longitudinal direction as spindle 22 . Thus, nut 32 also moves to the second end of housing 12 . The distance moved by nut 32 is the distance it moves relative to spindle 22 plus the distance spindle 22 moves relative to housing 12 .
[0061] The “on” position, shown in FIGS. 3 and 5 , is attained by reversal of the direction of rotation of handle 14 . This causes spindle 22 to move relative to housing 12 towards the first end, with nut 32 moving in the same longitudinal direction relative to spindle 22 .
[0062] Movement of spindle 22 towards its “on” position may be terminated on attaining that position by the leading end of portion 24 of spindle 22 contacting the inner surface of end wall 34 of handle 14 (as shown in FIG. 5 ). This, of course, is subject to spindle 22 not providing a force sufficient to displace handle 14 from housing 12 by disengaging groove 39 and bead 40 . Movement of spindle 22 towards its “off” position is terminated on attaining that position, shown in FIG. 4 , by an arrangement best understood by reference to FIGS. 9 and 10 . As can be seen from FIGS. 4, 5 , 9 and 10 , spindle 22 has a circumferential flange 45 located around the junction between its respective threaded portions 26 and 27 . At each of diametrically opposed locations, flange 45 has a respective outwardly extending tab 46 , 47 which serve respective purposes. The tab 46 has a side 46 a which leads in the direction of rotation as spindle 22 is rotated towards the “off” position. At the “off” position, side 46 a abuts against an end surface 48 a defined by a short arcuate bead 48 formed around and against a shoulder 19 a defined in passage 13 at step 19 . The side 46 a is inclined slightly with respect to a plane containing the rotational axis of spindle 22 , such that the radial outer edge leads slightly in rotation to the “off” position. This assists in ensuring that the spindle 22 is not able to move longitudinally beyond the “off” position, by preventing lateral deflection of spindle 22 to permit tab 46 to pass radially within bead 48 . The tab 47 also assists in this regard, in that it limits the freedom for spindle 22 to deflect laterally.
[0063] Rather than longitudinal movement of spindle 22 being terminated on attaining the “on” position by the end of portion 24 of spindle 22 contacting the inner surface of wall 34 of handle 14 , it is preferred that a gap be retained between that end of portion 24 and wall 34 . To enable this, longitudinal movement of spindle 22 on attaining the “on” position may be terminated by the threaded engagement between second nut 32 and second threaded portion 28 of spindle 22 . Thus, the end of the respective threads of nut 32 and portion 28 , at the end of each nearer to the second end of housing 12 , may define a respective end face similar in form and action to side 46 a of tab 46 and surface 48 a of bead 48 , with the end faces abutting to terminate longitudinal movement of spindle 22 at the “on” position.
[0064] The section 44 of nut 32 has a transverse opening 50 extending diametrically therethrough. Also, as best seen in FIG. 3 , and able to be appreciated from FIGS. 4 and 5 , there is a radial slot 52 cut in nut 32 which extends from the outer surface to the centreline of nut 32 and from opening 50 to the free end of nut 32 .
[0065] At the second end of housing 12 , there is a lateral opening 54 . The location of opening 54 is such that, with actuator 10 in its “off” position, opening 54 is laterally in-line with the end of opening 50 of nut 32 at which slot 52 is provided. Also, from opening 54 , housing 12 defines a slot 56 which extends to, and radially across, an end wall 58 of housing 12 . With actuator 10 in its “off” position, slot 56 is in line with slot 52 of nut 32 . Also, beyond end wall 58 , housing 10 has a part cylindrical extension 60 which has radial tabs 61 spaced around and extending inwardly from its free edge.
[0066] With actuator 10 in its “off” position of FIGS. 2 and 4 , Bowden cable system 16 is able to be connected to or disconnected from actuator 10 . For connection, a nipple 62 at the free end of cable 64 of the system 16 is able to be presented radially through opening 54 of housing 12 and into opening 50 of nut 32 . The cable 64 then is able to be moved through the slots 52 and 56 so as to extend longitudinally beyond the second end of housing 12 , with nipple 62 held captive in opening 50 . As the cable 16 is moved to this position, a termination 66 at the end of sleeve 68 of system is able to be located in and retained by an engagement member comprising wall 60 and its tabs 61 . As shown, the termination 66 has a peripheral flange 66 a which is a snap fit within wall 60 from which it is held against longitudinal extraction by tabs 61 . With the system 16 secured in relation to actuator 10 , operation of actuator 10 by rotation of handle 14 , to change from the “off” position to the “on” position results in the cable 64 being pulled through sleeve 68 and longitudinally within housing 12 , along passage 13 . As spindle 22 moves along passage 13 towards the first end of housing 12 , with its portion 24 received further into sleeve 38 of handle 14 , nut 32 is drawn onto portion 28 of spindle 22 . Thus, cable 64 is drawn along passage 13 by the combined action of spindle 22 moving relative to housing 12 and nut 32 moving relative to spindle 22 . Accordingly, the distance cable 64 is able to be drawn along passage 13 is the total distance moved by nut 32 due to those combined actions.
[0067] FIG. 11 shows a second embodiment of an actuator 110 according to the present invention. Parts of actuator 110 corresponding to those of actuator 10 of FIGS. 1 to 10 have the same reference numeral, plus 100 . Also, actuator 110 is substantially the same as actuator 10 , in both its form, operation and functioning, except as detailed herein. Thus, for actuator 110 , there is shown its housing 112 with lugs 120 and first nut retaining tab 141 defined by U-shaped slot 112 b , as well as its handle 114 .
[0068] While the actuator 10 of FIGS. 1 to 10 is intended for connection to an adjustable device, such as a vehicle seat lumbar support. via a Bowden cable system, the actuator 110 of FIG. 11 is adapted for direct connection to the adjustable device. As shown in FIG. 11 , the housing 112 of actuator 110 is able to be closed at the second end by its end wall 158 . However, adjacent to the second end, housing 112 defines two diametrically opposed elongate slots 102 . Additionally, part 144 of the second nut 132 does not necessitate a lateral opening and slot, corresponding to opening 50 and slot 52 of actuator 10 , for receiving the nipple and cable of a Bowden system. Rather, part 144 of nut 132 has a respective projection 104 extending laterally through each slot 102 .
[0069] The projections 104 provide means by which the actuator 110 is able to be operatively connected to an adjustable device. An end part D of such device is shown in broken outline in FIG. 11 . In the arrangement illustrated, the second end of actuator 110 extends into an aperture A of device D, between side portions S. Each projection 104 is journalled in a respective portion S of device D. The arrangement is such that, as actuator 110 is operated to move its spindle (not shown) and nut 132 between the “on” and “off” positions, projections 104 move along slots 102 with movement of nut 132 . This results in the end part D of the adjustable device being moved, such as to apply or release tension in, and thereby adjust, the adjustable device. Where the device is a lumbar support. having one end connected to one side of a vehicle seat-back frame, and its other end D connected to an actuator 110 mounted on the other side of the frame, the support can be adjusted to increase or decrease, respectively, the level of lumbar support provided to an occupant of the seat.
[0070] Operation with actuator 10 of FIGS. 1 to 10 can be similar. However, of course, adjustment of an adjustable device by actuator 10 is by movement transmitted via the Bowden cable system 16 .
[0071] The projections 104 may be formed integrally with part 144 of nut 132 . However, this would require that part D of the adjustable device is split, to enable projections 104 to be received therein, in the arrangement illustrated. Alternatively, the projections 104 may comprise a respective or common pin, bolt or the like separable from part 144 and securable in a lateral bore defined by part 144 after being inserted through part D. Such separable projection 104 may be securable in part 144 by screw threaded engagement in the lateral bore, or by any other suitable means.
[0072] In a variant on the embodiment of FIG. 11 , the part 144 of nut 132 may have a lateral bore, or oppositely opening lateral bores, and not include projections such as shown at 104 . With that variant, each side S of end part D of an adjustable device may have an integral projection locatable in a respective lateral bore of part 144 . Alternatively, each side S may define a bore through which a pin or bolt is able to be secured, with the pin or bolt journalled in the transverse bore of part 144 . In that alternative, there may be a respective pin or bolt for each side S, or part 144 may have a single through bore in which a common pin or bolt for each side S is journalled. That is, the through bore may be similar to opening 50 of actuator 10 of FIGS. 1 to 10 , but there need not be a slot similar to slot 52 of actuator 10 associated with the through bore.
[0073] Finally, it is to be understood that various alterations, modifications and/or additions may be introduced into the constructions and arrangements of parts previously described without departing from the spirit or ambit of the invention. | An actuator, connectable to and for adjusting a device, comprises a housing having a longitudinal passage extending between first and second ends and defining an opening at or adjacent to the second end, and a spindle supported in the housing and movable longitudinally in the housing passage. The spindle has two oppositely handed, longitudinally spaced threaded first and second portions respectively nearer to the first and second ends of the housing. A first threaded nut fixed relative to the housing is threadedly engaged with the first threaded portion. A handle rotatably mounted at the first end of the housing is coupled to the spindle for rotating the spindle in the first nut and thereby moving the spindle longitudinally relative to the first nut and the housing. A second nut fixed against rotation relative to the housing is threadedly engaged with the second threaded portion of the spindle and, in response to rotation of the spindle by the handle, is movable longitudinally in the housing passage relative to the spindle, in the same direction as movement of the spindle relative to the housing. Connecting means on or of the second nut is connectable, through the opening defined by the housing, to an adjustable device to be adjusted by the actuator. The spindle is rotatable by the handle for adjusting the adjustable device by longitudinal movement, in the same direction, of the spindle relative to the housing and of the second nut relative to the spindle. | 5 |
This application is a continuation of and claims priority from U.S. patent application Ser. No. 11/340,323 (now U.S. Pat. No. 7,201,554), filed Jan. 25, 2006; U.S. patent application Ser. No. 10/801,524 (now U.S. Pat. No. 6,991,423), filed Mar. 12, 2004; and U.S. Provisional Application Ser. No. 60/520,550, filed Nov. 14, 2003, the contents of each of which are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to methods and machines for stacking material, and more particularly, to methods and machines for stacking elongated planar members, such as sheets of lumber, plywood, or other material, into packages to facilitate subsequent shipping and/or handling.
2. Description of Related Art
The lumber industry, in particular, uses stacking machines (or stackers) to collect sheets (or pieces) of lumber, plywood, and other wood products into packages (or bundles) to facilitate bulk handling and shipping. Lumber is generally produced in lengths between 4′ to 28′, with thicknesses ranging from 1″ to 12″, and having widths that range between 2″ to 24″. After production, the lumber is generally gathered into layers (or courses) and then supplied to a stacker where it is formulated into packages that are typically approximately 16 to 30+ layers high and range from about 42″ to 96″ in width.
The stacking process requires robust machinery. It is also desirable to have a stacker that is capable of efficiently stacking the lumber at a very high speed. It is further desirable to have stacking machinery that is easy to maintain and that requires very little supervision or manual tuning during the stacking process. The longer the machines are kept up and running between down times and the less manual intervention that is required, the better the process efficiency. Greater efficiency results in increased production and enhanced profitability.
The industry is therefore in need of faster and more reliable methods and systems for stacking the materials that are to be bundled together. In particular, in sawmills and planer mills that manufacture lumber and other wood products, the speed of equipment that feeds conventional stackers has been increased, without a corresponding increase in the stacking speed. This results in bottlenecks and inefficiencies at the stackers.
Conventional stackers are generally unable to meet the high demands placed on them by current lumber feed systems. Typically, a package of lumber is formed in the stacker using a set of forks (or stacker arms) to raise a course of lumber from stacker chains. The arms are then extended to an area containing the accumulated courses. Once the course of lumber has been set on top of the stack, the stacker arms retreat to pick up the next course. This process is repeated until the desired number of courses have been set and a full package has been created. The package can then be bundled and shipped, or subjected to further processing.
U.S. Pat. Nos. 4,290,723 and 5,613,827, and Published U.S. Patent Application No. 20030031550, disclose various machinery and methods for stacking courses of lumber into packages. Unfortunately, none of these, or other known conventional stacker designs, are able to stack lumber at the high stacking rates required to keep up with the increased speed of present feed systems. Conventional systems, for example, are only capable of a maximum of about 15 cycles per minute for a single carriage stacker, and around 24 cycles per minute for a dual carriage stacker—not taking into account down time between loads being stacked and general inefficiencies of the infeed and outfeed systems of the stacker.
In addition, conventional stackers have not provided the ability to stack shorter courses of lumber at a faster rate. Typical infeed systems are often able to supply shorter courses of lumber at higher speeds, but, with no way to stack them faster, this higher feed capacity is wasted on conventional stackers. There are generally as many short lengths in a formulated layer of lumber as there would be longer lengths. This means that you have to stack 10′ long, 12″ wide pieces of lumber, produced at 120 pieces per minute, with 4 pieces per layer, at 30 layers per minute (120 pieces/4 pieces per layer) in order to keep up with the infeed system. This is in contrast to 20′ long, 12″ wide pieces that are produced at 60 pieces per minute, which would only need to be stacked at 15 layers per minute (60 pieces/4 pieces per layer). Mills therefore need to be able to stack about 30 courses per minute or more in order to keep up with the infeed of smaller lumber courses, and should also have very few timing and maintenance problems.
SUMMARY OF THE INVENTION
One objective of the present invention is to provide a stacker that is competitive in cost to build but that operates at higher speeds than conventional single or dual carriage stacker designs. According to one embodiment, the increased speed is preferably due to a simplified, positive actuating mechanism utilizing a higher degree of electronic controls. Simplified mechanical and electrical controls can result in a much faster stacking mechanism with little operation down time, lower maintenance, and less manual supervision and tuning requirements.
Dual stacking arms help stack faster, but without proper control, dual stacking arms cannot enable a fast, reliable, and efficient stacker. According to various principles of this invention, electronic control of the velocity and ramping of dual stacking arms is preferably provided to simultaneously and precisely control forward and rearward, as well as vertical, movement of the stacking arms. Precise electronic control enables the stacker to meet high production requirements with little supervision and maintenance. According to a preferred embodiment, a stacker can be made capable of cycling at approximately 35 to 40 layers per minute or more, depending on the size of the material pieces being handled.
In some traditional lumber stackers, the courses of lumber are picked up and stacked one course at a time. According to a preferred embodiment of this invention, however, the stacking machine picks up a subsequent course of lumber while the previous course is being set. To accomplish this, a high-speed stacking machine preferably includes two sets of forks (or arms) that operate complementary to one another. This significantly speeds up the rate at which the lumber is able to be stacked.
In addition to having two sets of arms working complementary to one another, the design of one preferred embodiment utilizes a rack and pinion system, driven by a linear positioning mechanism (such as a hydraulic cylinder, drive screw linear actuator, or other linear positioning device) to horizontally move and position the stacker arms. A vertical positioning device is also preferably included to raise and lower the stacker arms to the proper vertical position at the proper speed. An electronic control system can be used to precisely monitor and control the speed and ramping of the positioning systems. Precise control of the dual stacker arms, enabled through principles of this invention, allows the stacking machine to create packages of lumber at a faster rate than previous methods and machines with fewer timing and maintenance problems.
According to yet another aspect of this invention, in addition to providing the ability to stack lumber of all sizes and mixes at higher speeds, a high-speed stacker is also preferably configured to provide the ability to disengage unnecessary stacking arms. Disengaging extra stacking arms can reduce the mass that must be moved by the positioners, and thereby permit an increase in the speed of the remaining stacking arms. This is particularly advantageous in systems where sawmill and planer mill stacker infeed production equipment are able to produce a higher piece count of shorter courses. A clutching mechanism (or any other mechanical or electrical engagement/disengagement system) could be used to disengage unneeded stacking arms from the stacking process.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing and other objects, features, and advantages of the present invention will become more readily apparent from the following detailed description of various preferred embodiments, proceeding with reference to the accompanying drawings, in which:
FIG. 1 is a somewhat schematic top plan view of a stacking system having a stacker with plurality of stacker arm pairs configured according to a preferred embodiment of the present invention;
FIG. 2 is a somewhat schematic side elevation view of the stacking system of FIG. 1 ;
FIG. 3 is a somewhat schematic perspective view of a pair of stacking arms as used in the stacker shown in FIG. 1 ;
FIGS. 4A-4B are somewhat schematic top plan and side elevation views of a stacker, illustrating use of a linear positioning device to control horizontal movement of stacker arms according to another aspect of the present invention;
FIGS. 5A-5C are somewhat schematic side elevation views of a stacker, illustrating use of a linear positioning device to control vertical movement of stacker arms according to yet another aspect of the present invention;
FIGS. 6A-6H are somewhat schematic side elevation views illustrating the operation of a stacker configured according to the embodiment shown in FIG. 1 ;
FIG. 7 is schematic block diagram illustrating an electronic control system for controlling a stacking system, according to a still further aspect of the present invention; and
FIG. 8 is a schematic top plan view of a stacker illustrating a disengagement mechanism for disengaging one or more of the stacker arms from the system according to a still further aspect of the present invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Various aspects and embodiments of the present invention will now be described in greater detail with reference to the accompany drawings. Beginning with FIGS. 1-3 , a high-speed stacking system 100 according to a preferred embodiment includes a stacker infeed section 10 , a dual carriage stacker 20 , a package lift 40 , and an electronic control system 50 .
The stacker infeed section 10 preferably comprises a material conveyor 12 , an even ender (not shown), and a course make-up section 16 . The even ender aligns ends of the material pieces 60 with one another. The material conveyor 12 carries the material 60 (such as lumber, plywood, or other material) from a material supply to the course make-up section 16 (or pre-staging area). The material 60 can, for example, be formulated into courses 60 A, using the course dividing arms 24 and course stop arms 25 , in the course make-up section 16 of the stacker infeed section 10 . Alternatively, however, the courses 60 A can be formulated in a course accumulation area arranged above stacker chains 26 in the stacker 20 .
The dual-carriage stacker 20 preferably includes a structural steel frame 22 , course accumulator stops (or dividing arms) 24 , course stop arms (or front dropping stop) 25 , stacker chains 26 , stacker arms 27 , 28 , forward and rearward hard-coupled mechanics 30 (e.g., a rack and pinion system), and lift arms 33 , 34 . A horizontal, linear positioner 36 (see FIGS. 4A and 4B ) is preferably provided in communication with the stacker arms 27 , 28 to control their horizontal position. A separate vertical, linear positioner 38 (see FIGS. 5A-5C ) is preferably provided in communication with the lift arms 33 , 34 to control vertical movement of the stacker arms 27 , 28 . Course rake-off stops 39 are also preferably included to scrape the courses 60 A off the arms 27 , 28 onto the package lift 40 .
Referring now to FIGS. 1 through 4B , the stacker arms 27 , 28 are preferably arranged in opposing sets configured to operate complementary to each other. In this embodiment, for example, the stacker arms 27 , 28 can be mounted on a rack and pinion system 30 . The rack and pinion system 30 preferably includes racks 270 , 280 communicating with one or more pinion gears 32 . More specifically, a first set of stacker arms 27 are preferably arranged on racks 270 communicating with a top portion of the pinion gear 32 . A second set of stacker arms 28 are preferably arranged on racks 280 communicating with a bottom portion of a pinion gear 32 . The pinion gear 32 can include separate gear members 272 , 282 formed or mounted on a common shaft 275 extending transversely through the stacker 20 .
Because of their hard-coupled relationship through the rack and pinion system 30 , movement of a first set of stacker arms 27 preferably creates a complementary movement in an opposite set of stacker arms 28 . The horizontal positioner 36 preferably controls movement of the stacker arms 27 , 28 and can, for example, be coupled to one of the arms 27 or 28 or directly to the rack and pinion system 30 in the stacker 20 .
Accordingly, in this embodiment, by virtue of their mechanical relationship through the rack and pinion system 30 , as one of the arms 27 is driven to its unloading position, the other arm 28 is driven to a loading position. Therefore, only one horizontal positioner 36 is required to control movement of all of the stacker arm pairs 27 , 28 in the stacker 20 .
Of course, numerous other embodiments incorporating the principles of this invention are also possible. In one alternative embodiment, for instance, the forward arms could all be connected to each other, with the rearward arms separately connected to each other without a hard-coupled relationship between the forward and rearward sets of arms. Simultaneous movement of the forward arms could be provided using a first horizontal positioner with simultaneous movement of the rearward arms being provided by a separate, second horizontal positioner. Separate connection between the forward set of arms and the rearward set of arms could, for instance, be provided using separate rack and pinion systems for the forward and rearward sets of arms. Alternatively, all of the arms in a set could be mechanically connected together in another mechanical relationship (such as by a rigid or other mechanical connection).
In yet another embodiment, separate horizontal positioners could be used to control movement of each stacker arm pair independently. The relationship between the arms in each pair could be controlled via a separate hard-coupled mechanical relationship, such as a rack and pinion system or other mechanical system. In still another embodiment, each stacker arm could be controlled using its own horizontal positioner. Although significantly more expensive, this approach would offer flexibility in terms of the timing and control of the arms and would provide an electronic disengagement mechanism allowing unneeded stacker arms to be disengaged from the system by simply not operating the positioners for the extra stacker arms.
Referring now to FIGS. 5A-5C , the vertical position of all of the stacker arms 27 , 28 is preferably controlled using a single vertical positioner 38 . Lift arms 33 , 34 are preferably arranged in pairs to communicate with a pair of stacker arms 27 , 28 . In this embodiment, each of the pairs of lift arms 33 , 34 are preferably mounted on a common shaft 350 . A shaft arm 352 is preferably coupled to the shaft 350 to cause rotational movement of the shaft in response to operation of the vertical positioner 38 . For example, as shown in FIG. 5A , retraction of the vertical positioner 38 can be configured to raise a stacking arm (not shown) using one of the lift arms 33 . FIG. 5B shows that arrangement of the vertical positioner 38 in a middle position allows both arms 27 , 28 to be lowered, and FIG. 5C illustrates the vertical positioner 38 in an extended position, which raises a different stacking arm (not shown) using another one of the lift arms 34 . By arranging all of the lift arms 33 , 34 for the stacking arm pairs 27 , 28 on a common shaft 350 , a single vertical positioner 38 can be used to operate all of the lift arms 33 , 34 in the stacker.
Of course, numerous other embodiments are also possible. For instance, all of the lift arms for forward stacker arms could be controlled by one vertical positioner, with the lift arms for rearward stacker arms controlled by a separate vertical positioner. Alternatively, a separate vertical positioner for each stacker arm pair could be used. Another embodiment could use a separate vertical positioner for each lift arm. Other embodiments could use a single lift arm to raise both stacker arms in a stacker arm pair. It should also be noted that the lift arms can be configured in any mechanical relationship with an electrically-controlled positioner that would cause them to raise the stacker arms at the appropriate time in the stacking sequence. Accordingly, the invention is not limited to the specific embodiments disclosed herein.
In operation, the vertical and horizontal positioners 38 , 36 are preferably configured to operate in response to instructions from the electronic control system 50 (see FIGS. 1 and 7 ). Using electrically-controlled positioners 36 , 38 , the stacker arms 27 , 28 are able to be raised and lowered to load and unload courses in a precise sequence, timed with the forward and rearward movement of the arms 27 , 28 .
The vertical and horizontal positioners 36 , 38 are preferably electrically-controlled hydraulic cylinders, controlled through an electronic controller, such as a Temposonics feedback controller. The hydraulic cylinders also preferably include position monitoring devices that are able to precisely determine and report the position of the hydraulic shafts (or pistons) to the electronic control system 50 . The speed and ramping of the hydraulic cylinders are also preferably controllable through the electronic control system 50 .
Of course, other types and/or configurations of positioners are also contemplated within the scope of this invention. For instance, screw drive linear actuators, servo type positioning motor drives, electric motor drives with variable frequency internal or external positioning capability, or other positioning devices could be used in place of the hydraulic cylinders. Combinations of any or all of these types (or other types) of positioners could be used to supply the forward and rearward arm movement as well as the raising and lowering of the arms.
Regardless of the type of positioning device used, however, it is desirable to know the state of the positioner and to maintain precise electronic control over both positioning and ramping of the device. The horizontal positioner(s), in particular, are preferably configured to include an electronic positioning strip or other position detection device (arranged within or independently of the positioner) to enable determination of the horizontal positions of the stacker arms. The vertical positioners may also include position detection devices. Precise electronic control over positioning devices helps enable the stacker to operate at high-speeds without tossing material or otherwise jeopardizing the integrity of the stacking process.
FIGS. 6A-6H illustrate the operation of the embodiment of the stacking system 100 shown in FIG. 1 . It is desirable to have a stacking machine that is able to create packages of lumber or other material at a faster rate than previously available. Typically, a package of lumber is created by using a set of stacker arms to raise a course of lumber from the stacker chains and move it to a stacking area. The arms are extended out to the area containing the accumulated courses. Once the course of lumber has been set, the stacker arms retreat and pick up the next course. This process is repeated until the desired number of courses have been set and a full package has been created.
The dual-arm stacker 20 configuration according to the embodiment illustrated in FIGS. 1-3 contains two sets of forks 27 , 28 that operate complementary to one another. By picking up the next course of lumber while the previous course is being set, the rate at which the lumber is stacked can be significantly increased. To provide complementary-operating sets of arms, this specific embodiment preferably utilizes a hard-coupled mechanical drive system (such as a rack and pinion system) to arrange the stacker arms 27 , 28 in their back and forth horizontal positions. To achieve the necessary vertical motion of the stacking arms 27 , 28 , the system preferably utilizes vertical positioning arms 33 , 34 (lift arms) that raise and lower the stacking arms 27 , 28 to the proper vertical position.
A method of stacking material according to a preferred embodiment of the present invention will now be described in more detail with reference to FIGS. 6A-6H . Referring first to FIG. 6A , as the pieces of material 60 (such as lumber) are transferred down the infeed transfer 10 to the stacker 20 , a set of dividing arms 24 are preferably activated to start the formulation of, and the pre-staging of the courses 60 A of material. When the dividing arms 24 are lowered, the sheets of lumber (or other material) 60 travel to a course dividing section which may be located in a separate pre-staging area or at an infeed area of the stacker chains 26 . Course stop arms 25 , in conjunction with the dividing arms 24 , preferably limit the number of pieces of lumber 60 to the appropriate count for the course 60 A.
Referring now to FIG. 6B , once the course of lumber 60 A is created, a rearward set of stacker arms 27 is raised, thereby picking up the course of lumber 60 A. More particularly, lift arms 33 raise the fork arms 27 , which in turn raise the course of lumber 60 A from the chains 26 .
As illustrated in FIG. 6C , after the course 60 A has been lifted from the chains 26 , the rear forks 27 move forward with the course of lumber 60 A, while the front forks 28 are moved in the opposite direction. The front forks 28 ultimately end up in the position where the rearward forks 27 had been previously (see FIG. 6D ). This opposite, complementary motion can be created by the relationship of the stacker arms 27 , 28 to the location of the pinion gear 32 . As the pinion gear 32 rotates clockwise, the stacker arms 27 attached to the top of the pinion gear 32 move forward while the stacker arms 28 attached to the bottom portion of the pinion gear 32 move backwards. The opposite motion is created by rotating the pinion gear counterclockwise.
A hard-coupled mechanical drive system is preferably used to provide simultaneous complementary forward and rearward movement of the stacking arms. As discussed above, the mechanical drive system can comprise a gear rack and pinion gear activating mechanism for operating all of the arms simultaneously. The drive system could also comprise, however, dual sets of pinion gears on individual rack assemblies, for driving the forward and rearward arms independently. Other types of mechanical drive systems are also contemplated within the scope of this invention. However, those that provide simultaneous forward and rearward motion through a fixed mechanical relationship that does not change substantially with use or wear of the components are most preferred.
Referring now to FIGS. 6E and 6F , once the course of lumber 60 A has reached the location (e.g., the package lift 40 ) where the lumber package is being built, the lift arms 33 lower, thereby lowering the rear stacker arms 27 and setting the course of lumber 60 A in place on the package accumulation support 42 in the package lift 40 . When the lift arms 33 for the rearward stacker arms 27 are lowered, the lift arms 34 for the front stacker arms 28 are lifted, thereby raising the next course 60 B.
As shown in FIGS. 6G and 6H , the forward stacker arms 28 are then brought forward as the rearward stacker arms 27 are returned to their starting position. As the rearward arms 27 retreat from the package lift 40 , the course 60 A is scraped off the arms 27 by the course rake-off stop 39 . When the forward arms 28 reach the package lift 40 , the forward stacker arms 28 are then lowered using the lift arms 34 to deposit their course 60 B in the package lift 40 . The process is repeated until the desired package size has been achieved.
The package lift (or hoist) 40 preferably automatically adjusts the height of a package accumulation support 42 based on the number of layers accumulated thereon. In a preferred embodiment, for example, the package lift 40 can utilize positioners (not shown) to precisely place the accumulation support 42 in a proper receiving position with respect to the stacking arms 27 , 28 . The accumulation support 42 is thereby preferably configured to index the exact amount to accommodate successive layers. This system can reduce lost time and eliminate the need for other sensing devices that might otherwise be required.
Referring to FIG. 7 , an electronic control system 50 for the high-speed stacker 20 preferably includes a PLC or PC type of positioning and sequencing software 52 loaded into a PLC or PC type of controller hardware 54 , and an operators console 56 . The electronic control system 50 is preferably used to control the precise position and sequencing of the stacker components to permit operation of the stacker at high-speed.
Referring now to FIGS. 1 through 7 , in a preferred embodiment, a controller 54 for a dual-arm, high-speed stacking system 20 provides coordinated motion control of seven axes. These seven axes can include, for instance, a primary stacking arm (or reference) axis (which controls the horizontal positioner 36 to provide forward and backward movement of the stacking arms 27 , 28 ), a stacking arm lift axis (controlling the vertical positioner 38 to lift and lower the stacking arms 27 , 28 ), an infeed speed axis (providing analog speed control of the infeed chain 12 ), a course set-up axis (providing coordinated control of timing solenoids for the course dividing arms 24 and stop arms 25 ), a stacker chain speed axis (providing analog control of the speed of the stacker chains 26 ), a sticker or tie strip placement axis (providing control of a sticker placement positional timing solenoid (not shown)); and a hoist axis (controlling positioning of the package lift 40 ). Control of these seven axes preferably provides both velocity and positional coordination of each of the system components with the primary stacking arm axis (or reference axis).
As discussed earlier, the location and movement of the stacking arms 27 , 28 (e.g., the primary axis) are preferably controlled through a horizontal positioner 36 (such as a hydraulic cylinder). The horizontal positioner 36 is, in turn, controlled using a controller 54 A (such as a Temposonics feedback controller) in the electronic control system 50 . The primary axis is therefore used to transport a course of lumber 60 A from the stacker chains 26 to a package lift (or hoist) 40 that is used to accumulate multiple courses of lumber to form a complete package. Linear motion of this axis preferably includes a controlled acceleration/deceleration ramp at each end of the stroke, as well as constant velocity over a central portion of the stroke. From this primary motion, positions of the stacking arms 27 , 28 can be continuously monitored to provide timing and coordination to the other axes.
More particularly, as the stacking arms 27 , 28 stroke, for instance, the vertical positioner 38 (preferably a second hydraulic cylinder) can be controlled using a separate controller 54 B (e.g., a second Temposonics feedback controller) in the electronic control system 50 . The vertical positioner 38 positions the lift arms 33 , 34 to provide lift control of the stacking arms 27 , 28 based upon the position/motion of the arms 27 , 28 . The amount of lift can also be coordinated to maintain the arms at a fixed position above the package in the hoist 40 and, using the control system 50 , can be adjusted continuously over the stroke of the arms 27 , 28 . In a retracted position, each stacking arm 27 , 28 is preferably raised to lift a course 60 A from the stacker chains 26 . At full extension, each of the stacking arms 27 , 28 is preferably lowered onto the top of the package in the hoist 40 .
Concurrent with the cycling motion of the stacking arms 27 , 28 , lumber 60 is being separated into courses 60 A on the infeed chains 12 and the stacker chains 26 . Timed with the position of the stacking arms 27 , 28 , a complete course of lumber 60 A is sensed from the course separator arm 24 and the front dropping stop 25 . The stacker arms 27 , 28 are then raised to separate the lumber to build one course of the package. Both the incoming chains and the stacker chains 26 are preferably controlled using separate Variable Frequency Drives (VFDs) 54 C, 54 E to match their speed to the speed of the stacking arms 27 , 28 .
At the correct position in the stroke of the stacking arms 27 , 28 , the lumber 60 being held behind the course dividing arms 24 is released by lowering the arms 24 . The lumber 60 travels forward to the course stop arm (front dropping stop) 25 at the end of the stacker chains 26 . Again at the appropriate stroke, the course stop arm 25 is lowered to allow a course 60 A to enter the stacker chains 26 . Once the desired number of pieces have passed the stop arm 25 , the stop arm 25 is raised to accumulate another course. The timing for these actions is therefore preferably based upon the position and speed of the stacking arms 27 , 28 . Photocell detectors can be used to monitor when a complete course has been formulated behind the front dropping stop 25 . Actuation of the course separator arm 24 and stop 25 can be controlled using a positional timing solenoid controller 54 D. As the stacking arms 27 , 28 rise to pick up the course 60 A at the end of the stacker chains 26 , the stacker chains 26 may be stopped momentarily to insure proper transfer of the course 60 A onto the stacking arms 27 or 28 .
When the stacking arms 27 , 28 carrying a course of lumber (or other material) 60 A reach their full extension, it may be desirable to initiate placement of a set of stickers or tie strips on the top of, or within, the course for package drying or stability. The number of these stickers or tie strips in the package can be based upon package type and size and can be programmed within the controller. The point of initiation of this cycle can also be controlled relative to the cycle position of the stacking arms 27 , 28 using the control system 50 . A positional timing solenoid controller 54 F can be used to control sticker placement.
After the stacking arms 27 , 28 retract and the course is on top of the package in the hoist 40 , the hoist 40 is preferably lowered until a photocell detector (not shown) senses the top of the package. In a preferred embodiment, the next course is kept from being lowered until the package clears the photocell detector. A positional timing solenoid controller 54 G can be used to control the stacker hoist 40 .
These seven axes controllers 54 A- 54 G can provide an overall control package for monitoring and controlling the operation of a high-speed stacker system. Control and monitoring of the motors, hydraulic pumps, transfer chains, and roll cases helps to provide complete control over the timing and sequencing of the stacking system. Master control over each of the various system component controllers 54 A- 54 G can, for instance, be provided by a Programmable Logic Controller (PLC) 54 combined with a Delta Computer Systems, Inc. RMC100 Series Servo Motion Controller 58 for the Temposonic controllers 54 A. 54 B. A local Touchscreen MMI Terminal 59 can also be provided for monitoring and setup of the system.
FIG. 8 illustrates an embodiment of yet another aspect of the invention, in which a disengagement mechanism 80 can be provided to the stacking system 20 to allow disengagement of one or more of the stacker arms from the system when desired, such as when stacking shorter courses. Referring to FIG. 8 , a high speed stacker 20 can include a plurality of stacker arms 27 , 28 operated through a horizontal positioner (not shown). One or more of the stacker arms 27 , 28 can be removed from operation by disengaging them from the remaining stacking arms. In this particular embodiment, this is preferably accomplished by using a clutch 80 to disengage the extra stacker arms 27 A, 28 A and 27 B, 28 B from those that are needed to stack the course.
In this embodiment, for example, the clutching mechanism 80 can be arranged to disengage the stacker arms 27 A, 28 A for the fourteen foot and longer board lengths and the stacker arms 27 B, 28 B for the eighteen foot and longer board lengths. By disengaging stacker arms for board lengths greater than fourteen feet, shorter board lengths can be stacked more rapidly. Disengaging unnecessary stacker arms reduces the overall weight of the components required to be moved and therefore reduces the force required to be applied by the controlling cylinder(s) to overcome inertia and move the course. This also reduces wear and tear on the components.
Of course, other methods of engagement and disengagement are also within the contemplation of this invention. For example, mechanically mating shafts could be engaged and disengaged manually or using a solenoid or other electric device. Disengagement of extra stacking arms can also be accomplished in various other embodiments through other means. For example, when multiple electrically-controlled positioners are used to control separate stacking arms or stacking arm pairs, the positioners connected to the unneeded stacking arms could be caused to remain idle while only those needed for the stacking operation are used. As can be seen from the foregoing description, any mechanical or electrical method for disengaging extra stacking arms can be used to reduce system loads when stacking shorter materials. This, in turn, can provide increased efficiency and speed with respect to the remaining stacking arms.
Having described and illustrated the principles of the invention in a preferred embodiment thereof, it should be apparent that the invention can be modified in arrangement and detail without departing from such principles. Among other things, the terms “forward” and “rearward” have been used throughout the foregoing descriptions for reference purposes only and provide no limitation with respect to the structure of the various embodiments described herein. For example, the stacker arms 27 , 28 are each capable of being in either a forward or rearward position. We claim all modifications and variations coming within the spirit and scope of the following claims. | A high-speed stacker preferably includes dual stacking arms configured to operate complementary to one another. Most preferably, an electronic control system is provided to enable precise control over the speed and positioning of the stacker arms in both horizontal and vertical orientations. Linear motion devices (such as hydraulic cylinders, screw drive linear actuators, or other devices) can be used to position the arms horizontally and vertically in response to instructions from the electronic control system. In operation, the electronic control system preferably controls the speed and ramping of the stacker arms to repeatedly move courses of material from a feed system to a stacking area at a rapid rate with little maintenance. The high-speed stacker can also be configured to operate fewer than all of the stacker arms to facilitate faster stacking of smaller courses of material. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a Continuation-In-Part (CIP) of Ser. No. 09/343,098, filed Jun. 29, 1999, now abandoned.
FEDERAL SPONSORSHIP
[0002] Not Applicable
MICROFICHE
[0003] Not Applicable
BACKGROUND OF THE INVENTION
[0004] This invention relates generally to gaming apparatus and more specifically to golf practice apparatus wherein a simulated ball attached to a pivotal support structure is struck.
[0005] Golf requires an inordinate amount of practice to become and remain proficient. Outdoor ranges are climate dependent and inconvenient for many, indoor ranges are space limited, and captive ball apparatus currently available does not provide the serious golfer with sufficiently accurate ball trajectory feedback. When striking a captive ball apparatus, the serious golfer wants to know the landing range, trajectory height, and lateral offset of a free ball similarly struck to within about 5 meters/yards (m/yd). Achieving that accuracy requires a three-dimension (3D) initial velocity vector accurate to about 3 mps (10 fps) in magnitude, about 0.5 degrees in azimuth and elevation, and a spin rate around both vertical and horizontal axes to about 100 rpm. Spin about a ball's vertical axis causes horizontal lift and increased drag resulting in a laterally curved flight path and reduced range. Spin about a horizontal axis causes vertical lift, increases drag, and may increase or decrease trajectory height and range. According to U.S. Golf Association (USGA) data as reported in the February, 1999 Golf Digest, pgs 76-79, “Maxing Out Your Ball”, achieving an optimum horizontal axis spin rate of about 2200 rpm versus 3600 rpm typical of most golfers will add 20 to 30 yards (10 to 15 percent) for a ball well struck. Examples of the prior art having germane attributes, as underlined below, to this patent are found in U.S. Pat. Nos. 1,680,897; 3,743,296; 3.815.922; 4,940,236; 5,255,920; and 5,586,940.
[0006] U.S. Pat. No. 1,680,897 to Matteson in 1928 discloses a simulated ball mounted on an axle stem within a pivotal structure. Generators driven by the two axles produce current. Current from the pivotal axle is related to ball velocity and generally indicates distance. Current from the stem axle is related to spin rate about a vertical axis and generally indicates a laterally curved ball flight. Azimuth angle, elevation angle, and spin about the horizontal axis are not measured. U.S. Pat. No. 3,743,296 to Branz in 1973 discloses a simulated ball mounted on an axle stem within a pivotal structure attached to a pivotal yoke. Light cells measure pivotal structure rotation rate (tangential velocity) and generally indicates distance. Cams on the stem axle activate switches to determine spin rate about a vertical axis to generally indicate a hook or slice. Yoke rotation permits the simulated ball to strike one of an array of switches to indicate azimuth. Elevation angle and spin about the horizontal axis are not measured.
[0007] U.S. Pat. No. 3,815,922 to Brainard in 1974 discloses a golf ball tethered to a vertical post to which a strain gauge is mounted and about which the ball and tether rotate. The strain gauge measures centripetal force that is related to tangential velocity. Free ball distance is computed from the tangential velocity and some predetermined launch angle. Azimuth angle, elevation angle, and spin are not measured.
[0008] U.S. Pat. No. 4,940,236 to Allen in 1990 discloses a transducer (strain gauge) attached to the face of a golf club. The transducer measures the strike force magnitude in a direction generally perpendicular to the face of the club and the duration of the strike event. Means are provided to determine a distance a golf ball would travel when similarly struck by an unaltered golf club at some predetermined launch angle. Azimuth angle, elevation angle, and spin are not measured.
[0009] U.S. Pat. No. 5,255,920 to Mangeri in 1993 discloses a golf ball appended to a semi-rigid tether attached to a horizontal axle. A strain gauge equipped flexible disk, in close proximity to the tether, and a slotted disk turn with the axle. When struck, the tether turns the axle and distorts the flexible disk. Light modulated by a slotted disk determines tangential velocity and disk distortion determines azimuth. Distance is computed for a predetermined elevation angle. Elevation angle and spin are not measured.
[0010] U.S. Pat. No. 5,586,940 to Dosch, et. al. in 1996 discloses orthogonal load cells (strain gauges) to measure arresting forces of a tethered ball when struck. Means are provided to time integrate 3D arresting forces and determine momentum from which a 3D velocity vector of a free ball so struck is derived. Light sensors are disclosed to determine the face angle of the striking club with means to derive spin rate about a vertical axis of a free ball. These data are used to compute a trajectory of a free ball similarly struck. Spin about the horizontal axis is not measured. All prior art captive ball golf practice apparatus lack spin rate measurement about a horizontal axis and therefore can have errors exceeding 20 to 30 m/yd, far in excess of 5 m/yd needed by serious golfers. In general, the prior art focuses on measuring preliminary events such as club approach angle, on subsequent events such as the motion or arrest of a captive ball, and on external reactions such as club forces in an effort to reconstruct strike events within the captive ball that cause motion and spin. In doing so, sensor types and their numbers are increased, some components of the strike such as torque cannot be accurately reconstructed, and kinetic energy sinks such as spring compressions and tether extensions must be accommodated; all are error sources, detract from long-term calibration accuracy, and reduce the usefulness of a captive ball practice tee.
BRIEF SUMMARY OF THE INVENTION
[0011] Accordingly, the apparatus of this invention focuses on forces and torques within the captive ball that occur during a strike event. The apparatus comprises two separate segments of a simulated golf ball attached to opposing surfaces of a strain plate and a plurality of strain gauges mounted on the strain plate within the ball and on the plate's pivotal support structure. Strains are measured during a strike to the ball to determine a 3D strike force vector, torque components thereof, and strike event duration. Strains caused by centripetal force are also measured after the pivotal structure rotates clear of the striking club and are used to validate strike force measurements and calibration accuracy thereof. The strike force vector and strike duration are used to determine a 3D velocity vector of a free ball similarly struck. Torque content of the strike and strike duration yield both vertical and lateral spin rates. From these data, an accurate 3D trajectory of a free ball similarly struck is computed for display to the golfer.
[0012] It is an objective of this invention to:
[0013] 1. Provide accurate spin rates about both horizontal and vertical axes, as opposed only the vertical axis per the prior art, in addition to a 3D velocity vector so that a trajectory of a free ball similarly struck can be computed with the accuracy needed by the serious golfer.
[0014] 2. Characterize the actual strike event to minimize potential error sources, rather than attempt to reconstruct it by measuring preliminary events (club face angle, club approach angle, etc) or secondary events (arresting forces, rates of motion, switch activation, etc).
[0015] 3. Avoid measurement processes that employ kinetic energy sinks (e.g. tethers, springs, friction, etc) that detract from measurement accuracy and long-term calibration accuracy.
[0016] 4. Provide an apparatus that alerts the user when re-calibration is required.
[0017] 5. Provide an apparatus that, when struck, produces a familiar impact sensation.
[0018] 6. Minimize mechanical and electronic part count to make the apparatus affordable.
[0019] 7. Provide a robust apparatus that is safe and reliable.
[0020] How the invention addresses the shortcomings of the prior art and fulfills the requirements for a highly accurate and useful captive ball golf practice tee will become apparent from considering the ensuing description and drawings.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0021] [0021]FIG. 1 is a perspective view of captive ball apparatus employed by the present invention and the Cartesian coordinate system used to describe part locations, forces and velocities.
[0022] [0022]FIG. 2 is an exploded view of a preferred embodiment showing the interrelationship of simulated ball segments, supporting structures, and strain gauges used to measure strike forces.
[0023] [0023]FIG. 3 is a functional diagram depicting strain gauge voltage origins, and a means to encode the strain gauge voltages for digital processing.
[0024] [0024]FIG. 4 is a functional diagram of software providing the means to determine a strike force vector, strike time duration, strike force torque content and the initial velocity vector and spin rates required for accurate trajectory calculations.
[0025] [0025]FIG. 5 is a tabular listing of drawing call-outs used in FIGS. 1 - 4 and terms used in the specification.
DETAILED DESCRIPTION OF THE INVENTION
[0026] Essence of the Invention:
[0027] The essence of this invention is direct measurement of a strike force applied to a simulated golf ball in order to calculate an initial velocity vector, initial spin rates about both vertical and horizontal axes, and a trajectory of a free ball similarly struck with greater precision than heretofore possible. Forces of a striking golf club cause a pressure induced planar force within a golf ball that is approximately parallel to the face of the striking club. The planar force may be visualized as an infinite number of identical unit vectors that sum to the club's force vector in both magnitude and direction. The unit vectors act on ball material in their path causing the ball to move in the direction of the force vector in accordance with Newton's second law as it applies to momentum. The strike event lasts about 500 μs (microseconds) in which the strike force increases from zero magnitude to as much as 14,000 N (Newton) or 3,150 lb (pounds) in 250 μs and reduces to zero in an equal time. Spin results when the striking club's face is not perpendicular to the strike vector because the planar force unit vectors become unequally disposed about the ball center and thus cause torque. The apparatus described herein characterizes these golf strike phenomena by measuring relative strains produced in a plate inserted in the path of the planar force and by measuring strains produced in the plate's support member.
[0028] Coordinate System:
[0029] The apparatus for strike force characterization and determination of its effect on a free ball similarly struck is generally illustrated in FIG. 1. A Cartesian coordinate system is used to aid discussion of part locations, forces, velocities, spins, and free ball trajectories. The origin of the coordinate system is chosen to be the center of a simulated ball 1 when the apparatus is at a pre-strike, vertical position. The X-axis is parallel to an assembly axis 17 about which the ball 1 rotates when struck. The Y-axis is perpendicular to the X-axis and projects to the horizon. The Z-axis is perpendicular to both the X-axis and Y-axis and vertically bisects a column 21 supporting the ball 1 . For simplicity, strike force and initial velocity components directed along the X, Y, or Z-axis are hereafter referred to as X, Y, or Z forces or velocities with “strike”, “initial” and “component” being understood.
[0030] Key Elements:
[0031] Referring to FIG. 2, a ball segment 11 and a shell segment 12 comprise the simulated ball 1 of FIG. 1 and are attached to opposite sides of a support structure 2 . The support structure 2 comprises a column 21 , a strain plate 22 , a wedging plug 23 , a retaining collar 24 and axle extensions 25 . The key elements of the apparatus are the ball segment 11 that transfers the planar strike force, the strain plate 22 and support column 21 whose strains are proportional to the applied strike force, a set of strategically placed strain gauges 41 - 46 that output voltage in real time as a function of strain, and the wedging plug 23 that permits measurement of torque producing strains. Additional key elements needed for apparatus operation are an electronics unit 6 , shown in FIG. 1, that detects and encodes strain gauge voltages to a digital format, and a software means, installed in a personal computer 16 or the like, also shown in FIG. 1, that converts strain gauge voltages to a set of precision forces, velocities, and spin rates needed to accurately calculate a golf ball trajectory. Other elements of the apparatus, described later, are designed to increase apparatus durability, reduce inertia for a familiar impact sensation, and enhance appearance and/or utility.
[0032] The ball segment 11 of FIG. 2 is constructed of material selected from a group of elastomers having a compressibility needed for transferring planar forces and a resiliency needed to assure repeatability. The elastomers that form golf ball cores are typically doped with a high-density material or have a high-density center in order to achieve the maximum mass of 45.93 (1.62 oz.) within the minimum diameter of 42.67 mm (1.68″) allowed by the USGA. The covering material is made from elastomers formulated to have sufficient tensile strength to contain core expansion during a strike. A homogeneous, low compression, un-doped, solid core golf ball that may be machined to interface with the plate 22 and collar 24 is a good choice to obtain the desired mechanical properties and reduce the inertia of the apparatus. The means for attaching the ball segment 11 is a contact adhesive, such as a polyurethane mixture, applied to the plate 22 , a flat 35 of the ball segment 11 , and an unthreaded portion 32 of the retaining collar 24 . The ball segment 11 is laterally compressed, inserted into the collar 24 against the plate 22 , and allowed to expand against the unthreaded portion of the collar 32 whose slight curvature enhances retention. The material for the plate 22 , column 21 , collar 24 , and two axle extensions 25 is selected from a group having high tensile strength, low density, and resistance to impact and creep. Machining the column 21 , collar 24 , and axles 25 from a single piece of beta-type titanium is a good choice to achieve the desired combination of characteristics. Optimum dimensions to minimize inertia while maintaining structural integrity depend on the material, desired height of the ball segment 11 above the axles 25 , shape of the column 21 , and maximum strike forces anticipated. A generally rectangular column 21 having dimensions of about 65 mm (2.5″) in height, for example, tapering from a bottom width of about 32 mm (1¼″) to a minimum width of about 20 mm (¾″) and tapering from a top and bottom depth of about 13 mm (½″) to a minimum depth of about 6 mm (¼″) will sustain, with adequate margin, a 30 degree, maximum strike force whose X force component peaks at 7000 N (1575 lb). An axle 25 diameter of about 13 mm (½″) is sufficient for a maximum strike provided the distance from the column 21 to support within a journal ( 53 of FIG. 1) is no more than about 6 mm (¼″).
[0033] The collar 24 , wedging plug 23 , and strain plate 22 , as an assembled unit, must withstand a Y force peaking at about 14,000 N (3,150 lb) and an X force of 7,000 N (1,575 lb). Without the wedging plug 23 , a plate 22 thickness of about 3 mm (⅛″), machined as part of the collar 24 , would be required but would have undesirable strain characteristics and would add unacceptable weight to the assembly. Employing the wedging plug 23 stabilizes the center of the plate 22 , permitting useable responses from the strain gauges 41 - 44 , and permits weight reductions for both plate 22 and collar 24 . The wedging plug 23 , constructed as a multi-spoke wheel (further reducing weight), has a threaded rim 26 that mates with a collar threading 27 . A hub 28 and the rim 26 of the plug 23 support and stabilize the strain plate 22 . A radial thickness for the rim 26 of about 3 mm (⅛″) and a depth of about 5 mm ({fraction (3/16)}″) are good choices, in conjunction strength supplied by the collar 24 , to withstand the Y force. Four spokes 29 having a depth of about 9 mm (⅜″) and a width of about 3 mm (⅛″) are a good choice to stabilize the plate 22 . Heat-treated aluminum, such as 7075/T-651, is a good material choice for the wedging plug to provide the required strength while reducing assembly inertia.
[0034] A plate 22 thickness is selected whose strain under maximum load (10 N/mm 2 ) will not exceed the limits of the strain gauges 41 - 44 . As supported by the wedging plug 23 , a titanium plate 22 thickness, for example, of 1 to 2 mm ( {fraction (1/32)}″- {fraction (1/16)}″) has the necessary strength. At that thickness, radial areas 30 , having widths of about 3 mm (⅛″), are a reasonable choice for many strain gauge types. The plate 22 is attached to the plug 23 at its center and perimeter using machine screws 31 or the like. After mounting the strain gauges 41 - 44 , the resulting assembly is turned tightly into the threaded portion 27 of the collar 24 , the strain gauges 41 - 44 are aligned with the X and Z axes, and the ball segment 11 is then installed as described earlier.
[0035] The radial cross-section of the collar 24 is significantly reduced by employing the wedging plug 23 to increase the overall radial thickness of the combined structure as presented to an X force. Supported by the plug 23 , a collar 24 having a Y direction depth of about 13 mm (½″), for example, requires a minimum radial thickness where it joins the column 21 of about 9 mm (⅜″), but can be faired (excluding thread thickness) to about 1 mm ({fraction (1/32)}″) at 90 degrees and beyond to significantly reduce its inertia. A threading 27 width of about 6 mm (¼″) is a good choice to withstand the maximum anticipated Y force. A width of about 6 mm (¼″) for the unthreaded portion of the collar 32 is a good choice to restrain ball segment 11 lateral expansion for more efficient Y force transfer to the plate 22 , and for transferring the X and Z forces to the column. The shell segment 12 , which absorbs only modest arresting forces, is cast nylon or similar material having a minimum thickness of about 1 mm ({fraction (1/32)}″). Slots 33 or the like, cut into the spokes 29 , retain the shell 12 . A void 34 created by the shell 12 , the spoke-wheel construction of the wedging plug 23 , and the reduced thickness of the collar permitted by the wedging plug 23 are the primary means for achieving an apparatus inertia approaching that of a free ball and for giving the golfer a familiar impact sensation.
[0036] Strain Gauges:
[0037] Strain gauges locations are selected in conjunction with the selections of structure dimensions, structure materials and strain gauge type. Strain gauges for measurement of X and Z forces can be located on either the axle extensions 25 or on the column 21 . Strains that yield Y force appear at the plate 22 from strike forces and, as discussed later, at the column 21 from centripetal force. Strains that yield Z-axis torque appear at the plate 22 and at the column 21 . Strains yielding the X-axis torque appear only at the plate 22 . Accordingly, the preferred embodiment strain gauges 41 - 44 are mounted equidistant from the origin on the X-axis and Z-axis on four radial areas 30 of the plate 22 of FIG. 2 to characterize Y forces, including their X-axis and Z-axis torque content. The radial areas 30 are isolated from strains in other areas of the plate 22 and therefore react only to that portion of the planar strike force impinging directly on them. Isolation of the radial areas 30 is essential for torque measurements and is accomplished by attaching the center and perimeter of the plate 22 to the wedging screw 23 to eliminate transverse strain patterns typical of flat plates and by cutting radial slots 36 to truncate axial strain patterns also typical of flat plates. The X-axis strain gauges 41 - 42 produce positive voltages, +E −X and +E +X (subscripts denote location) whose difference is a measure of torque about the Z-axis. The Z-axis strain gauges 43 - 44 produce voltages, +E −Z and +E +Z , whose difference is a measure of torque about the X-axis. The voltage sum, E −X +E +X +E −Z +E +Z , is a measure of Y force.
[0038] The preferred embodiment employs strain gauges 45 - 46 mounted on the column 21 in the XZ plane and equidistant from the Z-axis to measure X and Z forces. The column mounted strain gauges 45 - 46 produce equal and same sign voltages, )E L and )E R , (subscripts denote left, right locations), from the Z force and equal but opposite sign voltages, )E L and *E R , from the X force. During the strike event, the sum of the column strain gauge 45 , 46 voltages is a measure of the Z force, and their difference is a measure of the X force. As the ball 11 rotates after the strike event has ended, but prior to arrest, the sum of the column strain gauge 45 - 46 voltages, +E LC and +E RC is a measure of centripetal force (subscript C denotes centripetal force). Centripetal force is used to correct Z force measurements and to validate measurement accuracy over prolonged use, as explained later. Strain gauges 41 - 46 are selected whose response characteristics will accommodate strains produced by the maximum and minimum anticipated forces at each mounting surface. For apparatus used in a range of temperatures, gauging both sides of a flexure beam is recommended to cancel gauge errors resulting from changes in gauge resistance.
[0039] Electronics Unit:
[0040] The electronics unit 6 , depicted as a functional diagram in FIG. 3, is selected from a group of signal conditioning units and designs available on the open market. Included are multi-function units, those with channel-dedicated analog to digital (A/D) devices, and those with a multiplexed A/D serving all channels. Many of the processes performed by the electronics unit 6 and the software, described later, may be performed by analog or digital means, as may be the preference of the designer. With today's technology, the preferred and least costly approach is to immediately convert the analog voltages to digital format using multiplexed A/D electronics as typified by the Cyber-Research INET 100 and controlled by the INET 230. The selected unit 6 has a minimum of six input channels 61 , a multiplexer 62 , A/D circuit 63 , a controller 64 , and power conditioning circuits 65 . Each input channel 61 is dedicated to sensing 110 , filtering 111 , and amplifying 112 one of the six strain gauge 41 - 46 voltages. While Nyquist theory requires only two samples, an A/D 63 dynamic range of at least ten bits and an encoding speed of about 120K samples per second (a minimum of ten samples per channel per event) is recommended to obtain the measurement increment and accuracy needed for precise trajectory calculations. The A/D circuit 63 continuously samples voltages from all channels 61 at programmed intervals. The controller 64 provides timing 66 for the A/D, controls multiplexer 67 switching, voltage thresholding 68 , and A/D calibration 69 . The thresholding 68 circuits compare every digital sample from a selected channel to a pre-determined value, typically two to three bits higher than noise, and permits data transfer from all channels to assigned segments of PC memory 70 when that value is exceeded. Data transfer is ended when the voltage of the threshold channel falls below the pre-selected value. While any of the plate 22 mounted strain gauge 41 - 44 voltages may be used to threshold the strike event, the voltage, E −Z , from the minus Z-axis strain gauge 43 , is recommended because it will tend to be the strongest signal. Following the strike event, as the apparatus rotates to arrest, the controller 64 is programmed to again transfer data from column-mounted strain gauges 45 - 46 , as voltages E LC and E RC (subscript indicates centripetal force). Voltage samples are time tagged by the controller 64 and sent serially to PC memory 70 . The controller 64 performs a calibration 69 of each input channel at start-up. A deviation from a normally quiescent zero state causes the controller 64 to adjust the A/D 63 encoding logic to account for the detected offset. The selected controller 64 is similar to the Cyber-Research INET 230 that contains a microprocessor to accommodate the real time functions described, and is constructed as a PCMCIA interface card for laptop computers or as a PCI card for internal PC environments (INET 200 ). The power conditioning circuits 65 supply regulated voltage to all electronics unit 6 circuits including the strain gauge 41 - 46 circuits.
[0041] Software:
[0042] The functions of a force/velocity software module shown in FIG. 4 provides the means to convert digitized strain gauge 41 - 46 voltage samples to forces, torques, angles, velocities, and spin rates as further explained in the operation section. The trajectory software is selected from a group that provides a time ordered trace of free ball flight as a function of initial 3D ball velocity, and spin about the ball's vertical and horizontal axes. One such trajectory computation software candidate that may be viewed at: http://www.telusplanet.net/public/maxs requires only minor modification to accommodate real time input and lateral spin. The PC 16 is one selected from a wide range of consumer PCs and requires only modest speed and memory capabilities.
[0043] Utility Items:
[0044] Referring to FIG. 1, the mounting base 5 comprises a teeing surface 51 , a base plate 52 for mounting axle journals 53 , a strain gauge cable assembly 54 , an arresting cushion 55 , a lever assembly 56 , and a small magnetic catch (not shown). The teeing surface 51 height is sufficient to permit the ball 1 to rotate clear from a striking club (not shown). A height of about 6 cm (2.5″) is a good choice. The teeing surface 51 is made of rigid plastic foam 57 or the like and a fibrous rubber mat 58 that will provide good traction and the resiliency needed to absorb club strikes. Multiple mats 58 are used to control ball height above the teeing surface 51 . For non-portable applications, the height of the surface may be reduced to that of the mat 58 with the journals 53 mounted in a prepared depression. Mats 57 such as those available from FiberBuilt Golf Mat Company are a good choice. The base plate 52 requires sufficient strength and weight to retain the journals 53 and provide the needed stability for accurate force measurements. Steel axle journals 53 with thermoplastic bearings and a large footprint are a good choice for stability. The material for the arresting cushion 55 is selected from a group having moderate resilience such that the energy of the struck ball 1 will be absorbed without rebound, yet return to its original shape in a few seconds. A gel contained by a strong silicone rubber sheathing material is a good choice. The cable assembly 54 houses a minimum of six bundles of four wires each, matching resistors to complete strain gauge voltage bridges (not shown), and a multi-pin connector 59 . The lever assembly 56 for returning the apparatus to vertical is a crank or other simple mechanism. The magnetic catch (not shown) comprises two small magnets similar in strength to those used in cabinet hardware and are attached to the column 21 and teeing surface 51 .
[0045] Apparatus Operation:
[0046] Referring to FIG. 1, a golfer stands on the teeing surface 51 and strikes the ball 1 which causes it to rotate clear from the strike into the arresting cushion 55 below the teeing surface 51 . He views a 3D trajectory and launch conditions of a free ball similarly struck on the PC 16 . The golfer actuates a lever 56 to return the ball 1 to vertical for the next strike with the ball 1 held vertical by a magnetic catch (not shown). The strike force, including the torque content thereof, and centripetal force cause non-zero voltages to appear at the six strain gauges 41 - 46 of FIG. 3. During the strike event, the support column 21 is deflected left or right by the X force and causes equal but opposite sign voltages, )E L and *E R , at the column mounted strain gauges 45 - 46 and whose instant values change as the force increases rapidly form zero to maximum and back to zero in about 500 us. The column 21 is simultaneously strained in tension or compression by the Z force and causes equal and same sign voltages, )E L and *E R . Centripetal force, gradually increasing during the strike, causes a positive delta in each of E L and E R . During the strike, the Y force and its torque content cause the strain plate 22 to deflect, positive voltages, +E −X , +E +X , +E −Z , and +E +Z , to be produced at strain gauges 41 - 44 , and the plate 22 to move about half a ball diameter (10 mm). Voltages at the plate 22 mounted strain gauges 41 - 44 go to zero after the strike event but the column 21 mounted strain gauges 45 - 46 voltages reduce to a steady state value reflecting centripetal force until motion is arrested. Voltages from the column 21 mounted strain gauges 45 - 46 are encoded during the strike as E L and E R and as E LC and E RC after the strike. All voltages are detected 110 , filtered 111 , amplified 112 , multiplexed 62 , and converted to digital samples 63 by the electronics unit 6 and routed to PC memory 70 as digitized, time tagged voltage samples.
[0047] Software Operation:
[0048] The means for converting strain gauge voltages to forces, velocities, and spin rates is the software residing in the PC 16 . Referring to FIG. 4, voltage samples are extracted from memory after completion of the encoding process. A mean value operation 71 sums magnitude-time increment products of the samples and divides by strike time duration: E i =Σe 1 Δt/ΔT. A strike time duration 72 calculation uses time tags to establish the strike duration, ΔT. The voltages are next converted to forces 73 by applying a separate calibration factor, S 41 for E −X , S 42 for E +X , S 43 for E −Z , S 44 for E +Z , S 45 for E L , and S 46 for E R (subscripts indicate strain gauge location), for each of the six strain gauge voltages. Force pairs are added and/or subtracted 74 - 79 as indicated if FIG. 5 to obtain measured values for X, Y and Z strike forces, F X , F Y , and F MZ ; torque about the X-axis and Z-axis, ω MX and ω MZ ; and centripetal force, F C . Forces F X , F Y , and F C require no correction, but F MZ contains a centripetal force component and torque values, ω MX and ω MZ , require corrections for strikes made at an angle to the Y axis (off-axis strikes) to compensate for the use of a sphere segment to measure spherical phenomena (the subscript M denotes measured).
[0049] Force F MZ is corrected 80 to eliminate the centripetal force from the measured value of the Z force: F Z =F MZ −QF C . By assuming the force impulse curve has a triangular shape (a constant rate of acceleration and deceleration), Q may be computed to be approximately 0.375. However, the value of Q is dependent on the materials selected for the ball segment 11 and on the inertia of the apparatus. Accordingly, calibration tests, described later, are performed to achieve the accuracy required for the Z force. After F Z is corrected, the force components in the XY and YZ planes and associated angles are computed 81 - 84 : F XY =(F X 2 +F Y 2 ) ½ ; F YZ =(F Y 2 +F Z 2 ) ½ ; ψ=sin −1 (F Z /F YZ ); and θ=sin =1 (F X /F XY ). The total strike force vector, consisting of magnitude F V , azimuth angle θ, and elevation angle, φ, is computed 84 - 86 : θ=sin =1 (F X /F XY ); F V =(F XY 2 +F Z 2 ) ½ ; and φ=sin −1 (F Z /F V ); Torque values, ω MX and ω MZ , are corrected 87 - 88 to remove apparent torque and further adjusted 89 - 90 in recognition that the torque measurements contain only the torque content of Y-axis directed force. Apparent torque is inherent when using a sphere segment to measure spherical forces. Strikes with no torque content made at non-zero azimuth/elevation angles can produce forces at the base of a sphere segment that are similar to the forces produced by strikes with torque content made at zero azimuth/elevation. Fortunately, the force vector is unaffected by torque content and may therefore be used to correct for apparent torque. Correction values, based on controlled tests made at varying azimuths and magnitudes while holding elevation at zero, are stored in a P Z table 91 . A table of P X values 92 is similarly established to correct torque about the X-axis. The pointers for accessing the P Z table 91 are θ and F XY . Accessing the P X table 92 is done with ψ and F ZY . Correction for apparent torque is performed 87 - 88 by subtraction: ω ZY =ω ZM −P Z and ω XY =ω XM −P X where ZY and XY subscripts indicate torque from the Y-axis directed force, only. Corrections 89 - 90 , to adjust for X-axis or Z-axis directed torque contributions, are performed by ratio: ω Z =ω ZY (F XY /F Y ) and ω X =ω XY (F ZY /F Y ). With the 3D force vector and true torque established, initial velocity magnitude, V V , and spin rates, ω Z and ω X , for a free ball are obtained 93 - 95 : V V =F V ΔT/M B ; ω Z =ω Z ΔT/I B ; and ω X =ω Z ΔT/I B ; where M B is free ball mass, I B is free ball moment of inertia, and ΔT is strike duration. Initial velocity, V V , spin rates, ω Z and ω X , plus initial azimuth and elevation angles, θ and φ, are sent to the trajectory software module where they are used to compute the trajectory of a free ball similarly struck.
[0050] Centripetal force, F C , used to correct the Z force 80 , is also used to validate strain gauge 41 - 46 measurements and indicate faults. The Y force, F Y , and tangential force, F T , are equivalent and may be determined, as is done at 76 F Y =F −X +F +X +F −Z +F +Z from voltages originating at strain gauges 4144 , or from data originating from strain gauges 45 - 46 using the relationship 96 between centripetal force and tangential force: F Y =F T =(1/ΔT)(F C RM A ) ½ where ΔT is strike duration, R is the radius of rotation of the ball 11 center, and M A is the effective mass of the apparatus. A difference in the two values suggests an error in one or more strain gauges, the calibration factors, in ΔT computation, or some combination thereof. The two values are therefore compared 97 to provide a means for validation/fault indication. If the difference 97 of the two values exceeds a predetermined limit, an alert message is displayed on the PC 16 indicating a system malfunction that requires repair and/or recalibration.
[0051] Apparatus Calibration:
[0052] Calibration tests are performed to obtain voltage-to-force factors S 41 -S 46 used for converting voltage to force 73 for each of the six strain gauges 41 - 46 used in the apparatus, to establish the Z force correction 80 value, Q, and to establish tables of values 91 - 92 used to correct for apparent torque. Prior to calibration testing, strains and associated voltages are calculated to assure strains, strain gauges and voltages are optimum for the selected configuration. Since the strain gauge 41 - 46 responses are linear and the installation is linear (no non-linear devices or energy drains), the tests will yield six voltage-to-force constants, one for each strain gauge reflecting both gauge factor and installation characteristics (S 41 -S 46 ), that are stored in PC memory 70 and applied to all future measurements. The voltage-to-force factors are obtained by applying known X, Y, and Z static forces to the apparatus. After the strain gauge 41 - 46 voltage-to-force constants have been established, values for apparent torque correction, P Z and P X , are collected, organized in tabular form, and placed in memory 91 - 92 . The Z-axis torque, ω X , correction values, P Z 91 , are established by holding elevation angle, ψ, at zero, applying a range of static forces, F XY , that vary in azimuth, θ, and magnitude, and by tabularizing 91 the apparent torque so obtained. The process is repeated with force magnitude, F ZY , and the angle from the YZ plane, ψ, being varied while holding azimuth, θ, at zero to establish a table 92 of X-axis apparent torque correction values, P X . The Z force correction 80 value, Q, is established from dynamic tests. An impulse force is applied whose vector coincides with the Y-axis. The Z and centripetal forces, F Z and F C , are recorded and their ratio yields the value for Q: Q=F Z /F C . Additional dynamic tests are recommended to verify apparatus accuracy and sensitivity over the range of strike force vectors and torque content anticipated during use.
[0053] Alternate Embodiments:
[0054] Additional embodiments, including those involving the selection of alternate strain gauge locations, analog versus digital designs, and hardware versus software techniques, are possible, too numerous to detail, and none of which change the basic functionality of the apparatus. Embodiments that reduce performance and eliminate functions, such as elimination of spin determination about the X-axis to reduce strain gauge count for example, are similarly within the scope of the present invention as defined by the claims. | Golf practice apparatus, comprising two sphere segments of a simulated golf ball mounted on opposing sides of a pivotal structure, strain gauges mounted on the structure to measure strains caused by a strike force to the simulated ball, means to digitally encode voltages resulting from the strains, and software for determining a three-dimension strike force, torque content thereof, and strike force duration. Strain gauges mounted on the structure between the ball segments determine one component of the strike force and torque about both horizontal and vertical axes. Strain gauges mounted on a support column of the pivotal structure determine the remaining strike force components. Additional software is disclosed for deriving an initial three-dimension velocity vector and spin rates about both horizontal and vertical axes of a free ball similarly struck whereby a three-dimension trajectory of a free golf ball may be computed. | 0 |
BACKGROUND OF THE INVENTION
U.S. Pat. No. 3,497,087 to one of the present inventors discloses an automatic vehicle parting system intended to provide a tiered parking structure the dense parking of parked vehicles. Such a construction contemplated significant economies in both site utilization and operation, providing parking for a plurality of vehicles upon a relatively limited land space area. In that inventor's subsequent U.S. Pat. No. 5,980,185, an improved automated parking garage structure is disclosed utilizing a rectilinear, rather than cylindrical structure.
The foregoing and other parking systems are of significant utility, as they each allow significant utilization of limited land space, allowing vehicles to be parked and stacked in a vertical-extending array. In general, such constructions are more efficient than conventional non-mechanized parking garage structures, where access is obtained through ramps sloping through the structure, the vehicles being driven, rather than carried, to a parking location.
Yet even these automated structures require a relatively large plot of land and are of a complex and expensive construction. While the number of vehicles which may be parked therein is large, the economies of scale require a large investment. Often there is a need for a parking structure of more limited capabilities. The land available may be impractical or insufficient for the construction of a parking structure having a large number of parking spaces on a given level, requiring expensive and complicated shuttle means to both raise the vehicle to the level and to direct the vehicle horizontally into a chosen one of a relatively large plurality of stalls. Alternatively, sufficient funds may be unavailable for a large structure, or the parking requirements for the location may be more modest.
It is accordingly a purpose of the present invention to provide an automated vehicle parking/storage facility capable of being constructed and operated on relatively small land areas.
Yet a further purpose of the present invention is to provide such a storage structure which is of economical construction and efficient operation.
Another purpose of the present invention is to provide a parking structure of the aforementioned general format which does not require driver assistance for vehicle parking or retrieval.
SUMMARY OF THE INVENTION
In accordance with the foregoing and other objects and purposes, a vehicle parking structure in accordance with the present invention comprises a structure having a central vertical elevator shaft having elevator means for raising an unoccupied vehicle to be parked or stored from an entrance level location to a chosen parking stage level or story and depositing the vehicle in an empty stall at the level, as well as for retrieving a parked vehicle from a stall and returning it to the entrance level location for departure from the structure. Each parking story comprises parking space for two vehicles, one space on each of opposite sides of the elevator shaft.
A vehicle to be parked is driven onto a tray on the elevator at the entrance level. The tray sits upon a shifter means that includes an extension mechanism which allows the tray to be extended and held outwardly of the elevator shaft in one of two opposite directions when the elevator is raised to the level of the intended vacant stall, to position the tray within the intended stall and lower the tray and vehicle onto supports in the stall. The extension mechanism then retracts and returns to a central, neutral position within the elevator shaft. The elevator can then be directed either to the entrance level to accommodate a new vehicle to be stored or to a parking level to retrieve a parked vehicle.
A parked vehicle is retrieved by positioning the elevator such that shifter is slightly below the level of the tray on which the vehicle is located, extending the extension mechanism to align with the vehicle, raising the elevator to lift the tray and vehicle from the supports and retracting the extension mechanism to the neutral position within the shaft The parked vehicle is then lowered to the entrance level stage for drive off.
An interlock system is provided to maintain a tray on the supports of a parking stall. The interlock is disengaged when the shifter deposits or removes a tray from the supports. Such as interlock is of significant value, particularly in high wind areas, since unoccupied trays are stored in the stalls and can be subject to large wind-induced forces. The shifting apparatus is of unique and simplified construction, allowing for efficient operation. A garage utilizing the elevator and shifter may be adapted to varying heights and parking levels, in accordance with the numbers of vehicles to be stored.
BRIEF DESCRIPTION OF THE DRAWINGS
A fuller understanding of the present invention will become apparent upon consideration of the following detailed description of a preferred, but nonetheless illustrative embodiment thereof, when reviewed in connection with the annexed drawings, wherein:
FIG. 1 is a front elevation view of an illustrative embodiment of the parking structure of the present invention;
FIG. 2 is a section view taken along line 2 — 2 of FIG. 1 depicting the elevator pit portion of the structure;
FIG. 3 is a section view taken along line 3 — 3 of FIG. 1 depicting the invention at ground level;
FIG. 4 is a section view taken along line 4 — 4 of FIG. 1 depicting the construction of the parking structure at a parking level and illustrating shift operation at a parking level;
FIG. 5 is a perspective view of a portion of the elevator at a parking level showing the shifter in an extended position;
FIG. 6 is a detail partial plan view depicting the drive for the shifter;
FIG. 7 is a partial section view taken along line 7 — 7 of FIG. 6;
FIG. 8 is a partial section view taken along line 8 — 8 of FIG. 7;
FIG. 9A is a top plan view of a portion of a stall showing a tray with a vehicle thereon being supported in the stall, the shifter being in alignment with the stall and the tray lock in the unlocked position;
FIG. 9B is a top plan view of the portion of the stall showing the a tray with a vehicle in the stall and the tray lock in the locked position;
FIG. 10 is a top plan view of the portion of the stall showing a tray and vehicle on the shifter having been lifted from the stall, the shifter being returned to the central position and the lock in the locked position;
FIG. 11 is a section view taken along line 11 — 11 of FIG. 9A;
FIG. 12 is a section view taken along line 12 — 12 of FIG. 11; and
FIG. 13 is a section view taken along line 13 — 13 of FIG. 11 .
DETAILED DESCRIPTION OF THE INVENTION
Referring initially to FIG. 1, parking structure 10 comprises a plurality of floors or levels 12 , each adapted to store two vehicles 14 in a pair of parking stalls 16 , each of which is on an opposite side of central elevator shaft 18 . The parking structure 10 may be economically constructed in a lattice-type construction, and may be of variable height, subject to zoning height restrictions, based upon the number of vehicles sought to be accommodated thereby. It is contemplated that upwards of ten parking floors or levels 12 can be accommodated in a structure of reasonable cost, thus allowing a maximum of 20 vehicles to be stored.
A series of vertically extending I-beams 20 extend vertically for the height of the structure, and are interconnected by horizontal beams 22 to establish the entrance and parking levels of the structure. As further seen in FIG. 2, four interiorly-located I-beams 20 define corners of the elevator shaft 18 , in which elevator 24 is installed for vertical travel between the entrance and parking levels 12 . The elevator 24 is dimensioned to support tray 26 , depicted in FIG. 3, the tray having a length and width sufficient to receive a vehicle 14 thereon, the vehicle being driven onto the tray from an end thereof when the elevator is positioned at the ground or entrance level. To allow the tray to be in general vertical alignment with the ground level of the structure, the elevator shaft may include a below-ground pit area, the floor of which serves as a portion of the base for the structure. As may be seen in FIG. 3, the tray 26 may include a pair of spaced guides 28 for the vehicle's tires to assist the driver in properly aligning and maintaining a vehicle on the tray as it is driven on and off the tray at the entrance level. A pair of stub beams 30 are mounted to each end of the tray at its the bottom surface to serve as supports for the tray when the tray is transferred to a parking stall, as will be discussed infra. The beams 30 may preferably be ID formed of box-beam segments welded to the aluminum tray, extending approximately 91 beyond the ends of the tray.
As also depicted in FIG. 3, the ground or entry level for the structure may include a peripheral wall 32 about the elevator shaft to protect users and operating personnel from inadvertently approaching the elevator shaft. Doors 34 allow controlled access to the elevator and the vehicle thereon.
With reference to FIG. 2, the elevator frame may be formed of a pair of spaced longitudinal beams 48 between which is located a support structure 50 for a drive motor 36 . A tray shifter assembly 52 is mounted transversely to the frame at the front and rear end of the elevator. The shifters support the vehicle tray 26 , allowing the tray to be directed to either side of the elevator as required. The construction details of the shifters are illustrated in FIGS. 7 and 8. Each shifter is preferably independently powered by its own electric motor, the motors operating in synchronism, such that both shifters work in unison.
Raising and lowering of the elevator is performed by the electric motor 36 mounted to the elevator frame. As further seen in FIG. 5, a pair of opposed transmission shafts 38 couple the motor shaft to gear boxes 40 at the front and rear ends of the elevator. Drive shafts 42 are provided with gears 44 at the ends thereof which mesh with vertical gear racks 46 mounted to the l-beams which form the perimeter of the elevator shaft way. An appropriate cable (not shown) provides electric power to the motor from a control box, preferably located at ground level. Appropriate sensors may be mounted to the elevator and positioned along the length of the elevator shaft to provide position information to allow the elevator to be positioned as appropriate with respect to the parking levels.
Referring further to the view of FIG. 5 in conjunction with FIGS. 6 and 7, each of the shifters 52 comprises a pair of right-angle members 54 which are bolted or otherwise affixed transversely to the main longitudinal elevator beams 48 . A series of opposed rollers 56 are mounted along the length of the right-angle members and support lower rolling beam assembly 58 . The lower rolling beam assembly 58 comprises a pair of upper and lower plates 60 separated and supported by box beams 62 . The height of the box beams 62 is chosen such that the plates 60 can straddle and capture the rollers 56 , the upper plate 60 riding on the rollers. The flanged construction of the rollers, along with the positioning of the box beams just inward of the rollers, maintains the positioning of the lower rolling beam assembly thereon.
Mounted to the upper plate 60 is a pair of upper rolling beam right angle supports 64 . The upper supports 64 are mounted to the lower rolling beam assembly 58 by bolts 66 , which also secure the upper and lower plates 60 and the box beams 62 of the lower rolling beam assembly together. The upper rolling beam supports 64 in turn have upper rollers 68 mounted thereto upon which upper rolling beam assembly 70 travels. The upper rolling beam assembly 70 is constructed in a manner analogous to that of the lower rolling beam assembly, and comprises a pair of spaced plates 72 separated by and mounted to box beams 74 . The upper and lower rolling beam assemblies 70 , 58 are thus arranged to extend in a cantilever fashion from the elevator and elevator beams 48 . Each of the rolling beams may be about 7 feet long, consistent with the width of the tray to be supported thereon which is of a similar width. The cantilever construction allows a tray to be extended outwardly to either side of the elevator so that it is fully beyond the width of the elevator shaft, as shown in FIG. 4, whereby the shifter-supported tray can be aligned with a parking stall and placed therein. The shifter can then be retracted and the elevator repositioned as needed for another vehicle.
The extension/retraction drive for both the lower and upper rolling beam assemblies 58 , 70 is provided by motor assembly 76 , which may include electric motor/gear box 78 . Motor bracket 82 , which supports the motor/gear box, is mounted to one of the upper rolling beam assembly supports 64 by a set of posts 84 . Thus, the motor drive unit travels with lower rolling beam assembly 58 .
The output shaft of the motor/gear box 78 bears pinion gear 86 which engages a pair of opposed gear racks 88 and 90 . The first gear rack 88 is mounted to right angle gear rack support 92 , which in turn is bolted one of the L members 54 . As the L member 54 is affixed to the elevator frame, motor operation drives the motor and thus rolling beam assembly 58 in extension to (or retraction from) one side or the other of the elevator with respect to the elevator frame. Second gear rack 90 is mounted to upper rack support 94 , which in turn is bolted to the upper rolling beam assembly 70 . Bolts 96 may affix the gear rack support 94 thereto, and at the same time, join the upper and lower plates 72 with the box beams 74 . It may be appreciated that, with the motor energized, at the same time as the lower rolling beam assembly extends out along the first fixed rollers 56 , the upper rolling beam assembly 70 extends relative to the lower rolling beam assembly. Upon reversal of the motor corresponding simultaneous retraction of both the upper and lower rolling beam assemblies is performed. The desired cantilever effect is thus produced.
The vehicle-receiving tray 26 is supported upon the shifters by the upper rack supports 94 , which may be in the form of right angle beams. The substantial mass of the tray in general is sufficient to maintain the tray in position on the shifters, both as it is raised and lowered by the elevator, as it is shifted laterally at a parking level, and when it is deposited at or lifted from a desired parking stall. To further insure stability when the tray is in a stall, however, an interlock system may be provided. When a tray is in the received position in a stall of the structure, the stub beams 30 of the tray are supported by and rest upon pairs of corresponding forward and rear tray support brackets 98 , mounted to the vertical I beam columns 20 that form the stall corners. To lock the stub beams and tray to the support brackets, the locking system depicted in FIGS. 9A-13 may be employed.
A pair of the stall support brackets 98 , either at the front or rear of the stall, is provided with a locking assembly 100 that is engaged by the shifter as the shifter is directed laterally into alignment with the stall. The locking assembly 100 comprises a pair of rotating finger or key lock elements 102 that rotate between two opposed perpendicular orientations, as depicted in FIGS. 9A and 9B. The keys are journaled in the horizontal portion of the support bracket 98 and project upwardly therefrom. The keys are dimensioned to engage with corresponding elongated apertures 106 located at the bottom surfaces of the box beam stubs 30 of the tray 26 when in a first orientation, and be perpendicular to the apertures in a second orientation. With the keys aligned with the apertures the tray can be placed on or raised from the support brackets. With the tray in position on the support brackets 98 and the keys perpendicular to the major length of the apertures, the stubs 30 , and thus the tray, is locked to and retained on the brackets.
Rotation of the keys in coordination with motion of the shifter is provided for as follows. Each of keys 102 is mounted on a shaft 104 . An elongated spacer bushing 108 surrounds the shaft below the bracket 98 , and a push arm 110 is affixed to the shaft below the spacer. The push arms 110 are in turn pivotally connected to main tie rod 112 . Reciprocating motion of the tie rod 112 thus pivots the keys. The inward facing end of the tie rod 112 is provided with a contact plate 114 . The contact plate 114 is aligned with actuator 116 mounted to the shifter. A bias spring 118 is connected between the main be rod 112 and a tray bracket 98 , whereby the locking assembly 100 is normally biased to the right as shown in FIG. 10, the keys 102 being perpendicular to the slots 106 in the box beam stubs 30 . With a tray in position on the support brackets, the lock is thus engaged.
FIG. 9B depicts a tray 26 and a vehicle 14 positioned on the tray brackets 98 and locked in a stall. When it is desired to retrieve the tray and vehicle, the vacant elevator is raised to the stall level and the shifter energized to move transversely into the stall slightly below the tray. As the shifter becomes generally aligned with the tray, the actuator 116 engages the plate 114 , driving the tie rod 112 to the left until the position depicted in FIG. 9A is reached. The shifter is now fully aligned with the tray, and the keys 102 have been pivoted 90 degrees counterclockwise such that they are in alignment with the apertures 106 in the box beam stubs. The tray is thus unlocked, and upward travel of the shifter allows the tray to be engaged thereby and lifted from the support brackets 98 . The shifter can then be retracted, bringing the tray into the elevator shaft, the pushrod assembly being returned to its rest (locked) position by bias spring 118 as the actuator 116 backs away from contact with the plate 114 .
Preferably the actuator 116 is centrally located on the shifter, and is appropriately dimensioned with a pair of opposed contact ends thereon to allow contact to be made with the pushrod assemblies associated with the parking stalls on both sides of the elevator as the shifter is moved thereto. When a vehicle is to be deposited in a stall, the elevator, with the vehicle-occupied tray on the shifters, is raised to a position whereby the tray on the shifter is slightly above the support brackets 98 of the intended receiving stall. The shifter is extended, and the actuator 116 contacts the plate 114 as the shifter and tray approaches final horizontal alignment within the stall. The contact and engagement with the plate rotates the keys 102 to their unlocked orientation as the tray is simultaneously brought into final horizontal alignment in the stall. The elevator is then incrementally lowered, lowering the tray onto the support brackets 98 , the elevator being further incrementally lowered to separate the shifter from the stall-supported tray with the shifter separated from the tray, retraction of the shifter into the elevator shaft disengages the pushrod assembly, allowing it to return to the rest position, locking the tray in position on the tray supports. It is to be noted that the contact plate 114 is of a sufficient surface area to allow continued contact with the actuator 116 during the incremental raising and lowering of the shifter during the deposit and removal of the tray from the support brackets. The actuator 116 may be provided with low friction tips, such as of Teflon or the like, to minimize frictional effects as the shifter is raised and lowered while the actuator is in contact with the plate.
Coordinated operation of the main elevator motor 36 and the shifter drive motors 78 is preferably performed by a microprocessor control system 120 , which may also monitor the location of occupied and unoccupied stalls and control the automated storage and retrieval of vehicles in the stalls. The control system may be located in operator's booth 122 and coupled to the motors, sensors and other operating elements by cabling as known in the art. The control system can provide for either attended or unattended operation. In typical operation each stall is provided with a tray which may be individually identified, such as by a bar coding which can be read by an appropriate sensor associated with the elevator/shifter. In an initial position, one of the trays is removed from its stall by the elevator/shifter and the elevator is positioned at the ground level to await receipt of a vehicle to be parked. The vehicle is driven onto the tray and the occupants exit. The occupants leave the elevator perimeter and the shaft way doors are closed. The control system is actuated, the tray and vehicle being raised to the level of the stall from which the tray was obtained, and the tray redeposited therein. As previously indicated, this is accomplished by the elevator initially being positioned by the control system such that the tray on the shifter is slightly above the level of the stall tray supports and the lock keys are cleared by the tray as the shifter is extended. As the shifter is extended the lock system is engaged, the lock keys being pivoted to the unlocked position. With the shifter emended such that the tray is properly aligned with the support brackets, the elevator is lowered to place the tray on the supports and separate the tray from the shifter. The shifter is then retracted, the lock keys returning to the neutral position, locking the tray on the supports.
With the shifter fully retracted the elevator can then be directed to a level to retrieve another tray for delivery to the ground level. The tray may either be occupied, if a command is entered to retrieve a parked vehicle, or may be unoccupied if there is a vehicle waiting to be parked. Once an occupied tray is retrieved and lowered to the ground level, the shaft way doors are opened, allowing the vehicle's occupants to enter the vehicle and drive the vehicle away. The elevator can then remain at the ground level, awaiting the entry of another vehicle which is placed in the empty stall from which the tray was retrieved, or can return the tray to its stall if another occupied tray is to be retrieved.
By incorporating a microprocessor control system, it is possible to develop and implement transfer routines that can improve the efficiency of system operation. If a stall is not provided with a tray, for example, it is possible to transfer occupied trays between stall locations. This can be of value in minimizing retrieval time, especially if the approximate return time for a vehicle is known. Vehicles having an earlier return time may be placed at the lower levels of the structure to minimize elevator travel time to expedite the retrieval process. Shifting of the vehicles between stalls can be performed during slack periods, and can be performed automatically by the control system according to appropriately designed algorithms. | A vehicle parking structure particularly well adapted for providing a parking capacity of up to about 20 vehicles has a structure framework with an entrance/exit level and a plurality of parking level floors, each of the floors having a pair of parking bays located on opposite sides of an elevator shaft. Vehicles to be parked are driven onto a vehicle tray, which is raised and lowered by means of an elevator in the elevator shaft. The elevator includes a shifter on which the tray is supported which allows the tray to be cantilevered outwardly from the elevator at a parking level. With the tray so cantilevered outwardly, the tray is incrementally lowered to rest on a pair of tray supports in the desired parking bay. The shifter is then retracted and the elevator can be raised or lowered to another level as required. To retrieve a vehicle, the elevator and shifter is positioned incrementally below the identified tray, and the shifter is extended into the bay. Raising the elevator incrementally lifts the tray from the parking bay such that it is supported by the shifter, which can then be retracted with the tray. The elevator is then raised or lowered as required. Operation of the elevator drive and the shifter may preferably be carried out under the control of a microprocessor control system. | 4 |
FIELD OF THE INVENTION
[0001] This invention relates to 2GT polyester-spandex circular-knit elastic fabrics which are dyed with disperse dyes. This invention also relates to a method of knitting, dyeing and finishing fabrics.
BACKGROUND OF THE INVENTION
[0002] Relatively small percentages of spandex fiber are frequently added to knit fabrics of ‘hard’ yarns, such as nylon, cotton, acrylic, wool and 2GT polyester, for example, in order to provide significant fabric stretch and recovery to the fabrics and the garments made therefrom. Hard yarns are relatively inelastic, which means that they can be stretched only very minor amounts without permanent deformation. As used herein, “spandex” means a manufactured fiber in which the fiber-forming substance is a long-chain synthetic polymer comprised of at least 85% of a segmented polyurethane. The polyurethane is prepared from a polyether glycol, a mixture of diisocyanates, and a chain extender and then melt-spun, dry-spun or wet-spun to form the spandex fiber.
[0003] For fabrics that are knit on circular, or weft, knitting machines the spandex is normally added as a bare yarn, without covering, and is fed in parallel with the hard yarn to the knitting needles. On its path from the feed package to the knit stitch, the spandex is under tension and is typically stretched, or drafted, 2.5× or more its original length; for example, drafting of 40 denier spandex yarn is typically 3.5×. Subsequent to knitting, the fabric is preset, scoured or cleaned, dyed, and then heatset to provide a colored fabric of desired dimensions and appearance. The method of dyeing and the types of dyes used depend mostly on the type of hard yarn used in the fabric, e.g., 2GT polyester, nylon, cotton, etc.
[0004] Fibers of polyethylene terephthalate (PET) polymer (hereinafter referred to as “2GT polyester” in this Specification) are hydrophobic and highly crystalline. Because the 2GT polyester contains no chemically active groups that interact with water-soluble dyes, the 2GT polyester can be dyed only with disperse dyes. The disperse dye class is so named because these dyes are almost insoluble in water and are used as finely divided aqueous dispersions (ref. ATI). Dyeing of 2GT polyester fibers is understood by many as a process wherein dye molecules penetrate into the 2GT polyester and into the available spaces among the 2GT polyester macromolecules. For the dye to penetrate the fiber to sufficient depths, in sufficient amounts and in a reasonable amount of time, the polymer structure must be ‘opened up’ to allow more efficient penetration of the dye molecules. If 2GT polyester is dyed in an aqueous solution at atmospheric pressure at 100 degrees C. or less, a ‘carrier’ is normally required to help open the 2GT polyester structure. A carrier is a chemical, such as chlorobenzene, orthophenyl phenol, aromatic esters, and chlorinated hydrocarbons, that adds cost to the process and also creates environmental problems when disposing of the dye bath liquids that contain the carriers. An alternative, which is most widely used, is to heat the aqueous solution to about 130 degrees C. in a pressure vessel for batch dyeing of the 2GT polyester-containing knit fabric. Such higher temperatures are sufficient to open the 2GT polyester fiber for efficient dyeing without the use of a carrier. High-pressure, high-temperature dyeing of 2GT polyester-containing knit fabric is almost always done now in equipment known as a jet dyer, wherein a loop of tubular knit fabric is moved in and out of the dye liquor by action of a venturi jet that uses the liquor (or alternately air) to forward the fabric.
[0005] Regardless of the particular 2GT polyester-dyeing method used, with or without carrier, it is well known that dyed 2GT polyester typically has a ‘washfastness’ problem wherein dye molecules can migrate to the 2GT polyester fiber surface and stain other fabrics and garments during clothes washing. The American Association of Textile Chemists and Colorists (AATCC) has developed standards to test the washfastness of dyed fabrics as measured by the staining of multifiber fabric test samples (e.g., acetate, cotton, polyamide, 2GT polyester, acrylic and wool) that are in the wash with the fabric whose washfastness is being tested. The individual fabric test samples are graded from 1 to 5, to indicate how much each has been stained by the dyed fabric being tested; a grade of 5 indicates no staining, wherein a grade of 1 indicates very significant staining. It is quite usual for 2GT polyester-dyed fabrics to stain companion polyamide fabrics, e.g., of nylon 6 and nylon 66 fibers, to a rating of 2 to 3.
[0006] Over time, the industry has learned various means and ways to reduce the 2GT polyester dye washfastness problem for specific cases. The choice of dye, in terms of color, shade and molecular structure, can result in more or less staining. Disperse dyes for dyeing PET are almost all made from chromophores of azo and anthraquinone, which have different structures and performance from one another. Dyes of other chromophores have been developed, which do give better washfastness performance, but these dyes are not in broad commercial use. Some dyes, azo and anthraquinone disperse dyes included, have more or less affinity for staining companion fabrics in a wash. Also, there are dyes with relatively large molecules and small molecules, and they are generally categorized as high energy to low energy dyes, respectively, as determined by the amount of energy to cause them to move into and out of the 2GT polyester or to sublimate. High energy dyes are also known as S-rated (or D) dyes by those in the trade. Middle energy dyes are also known as SE-rated (or C) dyes by those in the trade. Low energy dyes are also known as E-rated (or B) dyes by those in the trade.
[0007] Dyes of different shades stain more or less, with dyes of deep colors of red, black and blue being particularly susceptible to poor washfastness. Various methods for cleaning surface dye from fibers after dyeing have been developed, including reduction clearing. In reduction clearing, the fabric with dyed fibers is placed in a bath containing a reducing agent (e.g., hydrosulfite) and a base (e.g., sodium hydroxide); under the reduction-clearing process conditions, only the dye on the surface of the fibers is removed.
[0008] It is also known that heat treating 2GT polyester fibers, in order to reduce shrinkage or fix dimensions, also causes the phenomenon of thermomigration, wherein dye molecules migrate to the surface of the fiber and are then ready to stain other fabrics in the wash. Heat treating at high temperatures such as 175-200 degrees C. and higher is very detrimental to washfastness of dyed 2GT polyester fibers, so that heat treating of 2GT polyester fabrics is done before dyeing when possible. It is thus possible to use a combination of process step sequences, conditions and materials to mitigate dyed 2GT polyester washfastness for specific cases and types and colors of fabrics.
[0009] When spandex and 2GT polyester fibers are circular knit into elastic fabrics and subsequently dyed with an azo- or anthraquinone-based disperse dye, the problems of washfastness are worse, compared to washfastness of fabrics knit from 2GT polyester alone. Both the 2GT polyester and spandex are subject to thermomigration of dye molecules from the interior to the surface of the fibers. Further, in cut and sew fabrics, the last step in the circular-knit elastic fabric finishing process, after dyeing, is to heatset the fabric in open width at its desired length and width dimensions. This is necessary because the spandex, being elastic and having a retractive force after being drafted in knitting, will cause the final fabric to be too dense or have too much elastic elongation for the garment end-use desired. The final heatset step is necessary to achieve the final fabric desired properties, such as basis weight, stretch elongation, edge curl and appearance. To heatset the spandex at the desired open-width dimensions typically requires dry heat at temperatures of 175 to 185 degrees C. These temperatures result in significant thermomigration of the dye and poor fabric washfastness results as measured by staining of other fabrics in the wash. Because of the strong effect of heatsetting on 2GT polyester-spandex knit fabric washfastness, there are no means to improve washfastness to stain grading levels of 4 to 5, for such fabrics that are heatset as a final step and are dyed with middle energy, SE-rated or high energy, S-rated dye colors and dyeshades. As a result, the market opportunities are limited for 2GT polyester-spandex knit fabrics, and particularly for fabrics dyed into dark, rich colors. There is long-standing need for such fabrics that are adequately washfast, and for an economical method to make them.
[0010] U.S. Pat. No. 6,776,014 to Laycock, Leung and Singewald teaches a spandex-containing fabric and method for making the same. The method includes circular knitting with spandex at low draft and controlling the finishing and drying temperatures below the spandex heat set temperature.
SUMMARY OF THE INVENTION
[0011] The invention includes a dyed knit, elastic fabric comprising polyethylene terephthalate and spandex. The fabric has staining grade numbers of 4.0 or higher, as measured by staining of multifiber test fabrics in AATCC Test Method 61-1996-2A, and is dyed with disperse dyes comprising azo or anthraquinone molecular groups. The invention further includes a method for making the knit fabric.
[0012] An elastic knit fabric of the invention comprising 2GT polyester and spandex, can exhibit good azo- and anthraquinone-disperse dye washfastness and desirable physical properties. The invention further includes a method for making the knit fabric that avoids heat-setting the fabric under dry conditions at elevated temperature as further described below.
[0013] The invention may include a circular-knit single-jersey elastic fabric that may include bare spandex plated with yarns of 2GT polyester continuous filament, 2GT polyester staple or 2GT polyester staple blends. The fabric can be dyed with azo or anthraquinone disperse SE or S dyes, and the fabric may have an improved washfastness rating versus conventional fabrics when measured as staining nylon, cotton, 2GT polyester, wool, or acrylic in an accelerated laundering test per AATCC Test Method 61-1996-2A. The fabric can have a basis weight in the range of 160 to 330 g/m2, and an elongation of 80% or more, for example from 80% to 130% in the length (warp) direction. Further, said fabric can have a spandex content by weight of 4% to 15% and a shrinkage after washing and drying of about 3% or less, and for example less than 3% in both length and width direction.
[0014] The invention also may include a garment made from the fabric described above. Such garments may be top-weight garments.
[0015] The invention can include a method for knitting, dyeing and finishing a knit elastic fabric comprising 2GT polyester and spandex, without open-width dry heat setting after dyeing. For example, the method may produce a single jersey circular knit fabric. The spandex feed yarn can range from about 17 to about 44 dtex and the 2GT polyester yarn can range from about 55 to about 165 dtex, with the 2GT polyester dtex per filament ranging from about 0.05 to about 3.5. The stitch length and 2GT polyester dtex can be selected so that the knit cover factor ranges from about 1.1 to about 1.6, and for example from about 1.2 to about 1.4. During knitting, the spandex yarn and 2GT polyester yarn may be plated in every course and the draft of the spandex feed yarn may be controlled so that the spandex yarn may be drafted no more than about 2× or about 2.5× its original length, depending on the embodiment of the method. In a first embodiment, the knit fabric can be disperse dyed at atmospheric pressure at dye liquor temperatures of about 100 degrees C. or less, typically with a carrier, and the total spandex draft after knitting may be limited to about 2×. In a second embodiment the knit fabric is disperse dyed above atmospheric pressure at dye liquor temperatures ranging from about 110 to about 135 degrees C., and the total spandex draft after knitting is limited to about 2.5×. The dye liquor may contain azo or anthraquinone disperse dyes. Following dyeing, the fabric can be reduction-cleared and rinsed in order to remove excess dye from the surface of the fibers, and can then be air dried in open width in a tenter frame oven. The open width fabric may be held at its natural width and length and heated until dry. The air drying temperature can be a maximum of about 130 degrees C. or less, and can be for example from about 120 to about 125 degrees C. These drying temperatures are the maximum dry heat temperatures that the fabric will experience in finishing after the dyeing step.
[0016] The invention also may include the circular knit, elastic, single jersey fabrics made according to the inventive method, and garments constructed from such fabrics.
BRIEF DESCRIPTION OF THE FIGURES
[0017] FIG. 1 illustrates plated knit stitches comprising a hard yarn and spandex.
[0018] FIG. 2 is a schematic diagram of a portion of a circular knitting machine fed with a spandex feed and a hard yarn feed.
[0019] FIG. 3 illustrates a series of single jersey knit stitches and highlights one stitch of stitch length “L”.
[0020] FIG. 4 is a flow chart showing standard process steps for knitting, dyeing and finishing 2GT polyester-spandex circular-knit, elastic, single-knit jersey fabrics.
[0021] FIG. 5 is a flow chart showing the inventive process steps for knitting, dyeing and finishing 2GT polyester-spandex circular-knit, elastic, single-knit jersey fabrics.
[0022] While the invention will be described in connection with embodiments below, it is to be understood that the invention is in no way intended to be limited by such description. On the contrary, it is intended to cover all alternatives, modifications and equivalents as may be included within the true spirit and scope of the invention as defined by the claims appended hereto.
DETAILED DESCRIPTION OF THE INVENTION
[0023] Knit fabrics of the invention may include those fabrics of a single-jersey stitch, with bare spandex plated in every course. The term “Commercially-useful” as used herein refers to ranges of physical properties (including fabric basis weight, washfastness, elongation, stability and appearance) that can be associated with apparel fabrics.
[0024] FIG. 4 shows a flow diagram of a process 40 for making, dyeing and finishing circular knit fabrics of 2GT polyester-spandex. Depending on the knitting machine, the circular knit fabric will be knit into a tube, or cut into an open width (sheet) at the exit of the machine. The spandex is highly drafted, e.g., 3.5× for 44 dtex spandex, as it is plated into the knit stitches with the hard yarn. If the fabric is in tubular form at the exit of the knitting machine, the fabric is slit open 44 in a separate step before being relaxed and preset in a tenter oven 46 , at temperatures typically at 190 degrees C., but typically for a very short residence time of 45-60 seconds. The purpose of this process step is to relax the spandex tension. Subsequent to relaxation and preset, the open fabric is sewn back into a tubular form 48 for multiple sequential operations in a jet-dye machine 50 . While there are many variations of design of jet dye machines, they are all batch devices that circulate a tube of fabric, by means of a venturi jet that uses bath liquid, continuously into and out of a liquid bath of cleanser/bleach, or dye liquor, or caustic solution, as the case may be in the process step being performed. For cleaning, bleaching and reduction-clearing operations, the jet dye machine is operated at atmospheric pressure and liquid temperatures of 100 degrees C. or less. Some specific chemicals, processing conditions and process residence times are given in the Examples. For dyeing the 2GT polyester-spandex fabric, the jet-dye machine may be loaded both with fabric and dye liquor, pressurized and heated to about 130 degrees C., and then operated by circulating the fabric through the dye liquor at specified process conditions and residence time sequences. One variable of importance is the liquor ratio, or the ratio of fabric weight to the weight of the dye liquor in the jet-dye machine.
[0025] After the above cleaning, bleaching, dyeing, and reduction-clearing operations, the fabric is removed from the jet dyer and dewatered 52 in a centrifuge or in squeeze rollers, for example. The tubular fabric is then un-sewn (de-tacked) 54 and opened once again into an open-width (sheet) fabric.
[0026] The dewatered, open-width 2GT polyester-spandex knit fabric is then processed in a tenter frame oven, to heat set the fabric into desired and stable length and width dimensions. The tenter frame stretches the fabric to desired dimensions in both width and length, and heatsets the spandex and 2GT polyester fibers by heating them to about 180 degrees C. or more for a typical residence time of about 60 to about 120 seconds.
[0027] In the process of FIG. 4 , final fabric heatsetting 56 is the step that determines the final physical properties of the fabric, including basis weight, elongation, stability and appearance. For 2GT polyester-spandex single-jersey knit fabrics with spandex plated in every knit course, and for top weight garments, commercially-useful physical properties include the following:
basis weights from about 160 to about 330 g/m2, minimum elongation of about 80% in the length (warp) direction, spandex content from about 4% to about 15% of the total fabric weight, and shrinkage after washing and drying of about 3% or less in width and length.
Fabric physical properties in these ranges can be readily achieved by final tenter-frame heatsetting. As noted above, however, the heatsetting operation significantly reduces the dye washfastness of 2GT polyester-spandex knit fabrics, and it is generally not possible to achieve dye washfastness ratings of 4 to 5, particularly for SE and S-rated (including commercial high energy dyes) that are of deep color and/or shade.
[0032] FIG. 5 shows a process that eliminates the pre-heat setting and the final heat setting step, thereby improving the dye washfastness of the fabric. The selection of the knitting method used in the invention depends on the ‘wet-finishing’ conditions of the process steps after knitting. Wet-finishing refers to all process operations in which the fabric is wet, such as scouring, bleaching, dyeing and reduction-clearing operations.
[0033] In a first embodiment the total draft of the spandex yarn in knitting can be about 2.0× or less and the liquid temperatures in any of the wet-finishing steps, including dyeing, may range from about 80 to about 100 degrees C. In a second embodiment the total draft of the spandex yarn in knitting may be about 2.5× or less and the liquid temperature of the dyeing step may range from about 110 to about 135 degrees C.
[0034] FIG. 2 shows in schematic form one feed position 20 of a circular knitting machine having a series of knitting needles 22 that move reciprocally as indicated by the arrow 24 in response to a cam (not shown) below a rotating cylinder (not shown) that holds the needles. In a circular knitting machine, there are multiple numbers of these feed positions arranged in a circle, so as to feed individual knitting positions as the knitting needles, carried by the moving cylinder, are rotated past the positions.
[0035] For plating knit operations, a spandex yarn 12 and a 2GT polyester fully drawn, or hard, yarn 14 are delivered to the knitting needles 22 by a carrier plate 26 . The carrier plate 26 simultaneously directs both yarns to the knitting position. The spandex yarn 12 and 2GT polyester yarn 14 are introduced to the knitting needles 22 at the same or at a similar rate to form a single jersey knit stitch 10 like that shown in FIG. 1 .
[0036] The 2GT polyester yarn 14 is delivered from a wound yarn package 28 to an accumulator 30 that meters the yarn to the carrier plate 26 and knitting needles 22 . The 2GT polyester yarn 14 passes over a feed roll 32 and through a guide hole 34 in the carrier plate 26 . Optionally, more than one 2GT polyester yarn may be delivered to the knitting needles via different guide holes in the carrier plate 26 .
[0037] The spandex can be any commercially available elastane product for circular knitting, such as Lycra® spandex types 162 and 169, available from INVISTA S. á r. l. of Wichita, Kans. and Wilmington, Del.
[0038] The spandex 12 is delivered from a surface driven package 36 and past a broken end detector 39 and change of direction roll(s) 37 to a guide slot 38 within the carrier plate 26 . The feed tension of the spandex 12 is measured between the detector 39 and drive roll 37 , or alternatively between the surface driven package 36 and roll 37 if the broken end detector is not used. The guide hole 34 and guide slot 38 are separated from one another in the carrier plate 26 so as to present the hard yarn 14 and spandex 12 to the knitting needles 22 in side by side, generally parallel relation (plated).
[0039] The spandex stretches (drafts) when it is delivered from the supply package to the carrier plate and in turn to the knit stitch due to the difference between the stitch use rate and the feed rate from the spandex supply package. The ratio of the 2GT polyester yarn supply rate (meters/min) to the spandex supply rate is normally 2.5 to 4 times (2.5× to 4×) greater, and is known as the machine draft. This corresponds to spandex elongation of 150% to 300%, or more. The feed tension in the spandex yarn is directly related to the draft (elongation) of the spandex yarn. This feed tension is typically maintained at values consistent with high machine drafts for the spandex.
[0040] In two embodiments of the methods of the invention, the total spandex draft can be about 2.0× or less, or about 2.5× or less, respectively. These draft values are for the total draft of the spandex, which may include any drafting or drawing of the spandex that is included in the supply package of as-spun yarn. The value of residual draft from spinning is termed package relaxation, “PR”, and it typically ranges from 0.05 to 0.15 for the spandex used in circular knit, elastic, single jersey fabrics. The total draft of the spandex in the fabric is therefore MD*(1+PR), where “MD” is the knitting machine draft. The knitting machine draft is the ratio of hard yarn feed rate to spandex feed rate, both from their respective supply packages.
[0041] Because of its stress-strain properties, spandex yarn drafts (draws) more as the tension applied to the spandex increases; conversely, the more that the spandex is drafted, the higher the tension in the yarn. A typical spandex yarn path, in a circular knitting machine, is schematically shown in FIG. 2 . The spandex yarn 12 is metered from the supply package 36 , over or through a broken end detector 39 , over one or more change-of-direction rolls 37 , and then to the carrier plate 26 , which guides the spandex to the knitting needles 22 and into the stitch. There is a build-up of tension in the spandex yarn as it passes from the supply package and over each device or roller, due to frictional forces imparted by each device or roller that touches the spandex. The total draft of the spandex at the stitch is related therefore to the sum of the tensions throughout the spandex path.
[0042] The spandex feed tension is measured between the broken end detector 39 and the roll 37 shown in FIG. 2 . Alternatively, the spandex feed tension is measured between the surface driven package 36 and roll 37 if the broken end detector 39 is not used. The higher this tension is set and controlled, the greater the spandex draft will be in the fabric, and vice versa. Suitable ranges for this feed tension includes from about 2 to 4 cN for 22 dtex spandex, and from about 4 to 6 cN for 44 dtex spandex in commercial circular knitting machines. With these feed tension settings and the additional tensions imposed by subsequent yarn-path friction, the spandex in commercial knitting machines normally will be drafted significantly more than 2.5×.
[0043] Minimizing the spandex friction between the supply package and the knit stitch helps keep the spandex feed tensions sufficiently high for reliable spandex feeding when the spandex draft in about 2.5× or less.
[0044] The structural design of a circular knit fabric can be characterized in part by the “openness” of each knit stitch. This “openness” may be related to the percentage of the area that is open versus that which is covered by the yarn in each stitch (see, e.g., FIGS. 1 and 3 ), and is thus related to fabric basis weight and elongation potential. For rigid, non-elastic weft knit fabrics, the Cover Factor (“Cf”) is well known as a relative measure of openness. The Cover Factor is a ratio and is defined as:
Cf ={square root}( tex )÷ L
where tex is the grams weight of 1000 meters of the 2GT polyester yarn and is also equal to 10*dtex, and L is the stitch length in millimeters. FIG. 3 is a schematic of a single knit jersey stitch pattern. One of the stitches in the pattern has been highlighted to show how the stitch length, “L” is defined.
[0045] The knitting method can produce commercially useful circular knit, elastic, single jersey fabrics plated from bare spandex and 2GT polyester yarn without heat setting with spandex draft at about 2.0× or less in one embodiment, and at 2.5× or less in another embodiment for knit fabric is designed and manufactured within the following limits:
The Cover Factor, which characterizes the openness of the knit structure, can be between about 1.1 and about 1.6, for example between about 1.2 and about 1.4; The 2GT polyester yarn decitex may be from about 55 to about 165; The spandex decitex may range from about 17 to about 44: The content of spandex in the fabric, on a % weight basis, can be from about 4% to about 15%;
While not wishing to be bound by any one theory, it is believed that the hard yarn in the knit structure resists the spandex force that acts to compress the knit stitch. The effectiveness of this resistance is related to the knit structure, as defined by the Cover Factor. For a given 2GT polyester yarn decitex, the Cover Factor is inversely proportional to the stitch length, L. This length is adjustable on the knitting machine, and is therefore a key variable for control in this process.
[0050] After knitting a circular knit, elastic, single jersey fabric of plated spandex with 2GT polyester 62 , the tubular fabric can be scoured in a cleaning solution, typically in a jet dye machine 64 , FIG. 5 . Bleaching of the fabric is also an optional operation in this equipment. These operations are well known to those familiar with the art, and standard methods are satisfactory for the process.
[0051] The process may include dyeing at atmospheric conditions or at elevated temperatures and pressures 64 . Jet dyeing of 2GT polyester and 2GT polyester-spandex fabrics is well known to those who practice the art. Fabric and dye liquor are typically loaded into a jet-dye machine at weight ratios ranging from 1:10 to 1:15, which is the ratio of the weight of the fabric to the weight of the dye liquor. For the purpose of this invention, azo- or anthraquinone-disperse dyes are specified. The temperature of the dye liquor may be typically about 130 degrees C., but it can range from about 110 to about 135 degrees C., depending on the dye color and type. Dyeing conditions of temperature rise/decline rates and residence times at maximum temperatures are presumed to be best industry practice for the dyes used, and no special dyeing conditions or steps are needed for the process of this invention.
[0052] Standard industry practices are suitable for the dewatering 66 and slitting steps 68 .
[0053] The drying step 70 can be operated with controlled overfeed in the length (machine) direction so that the fabric stitches are free to move and rearrange without tension. A flat, non-wrinkled or non-buckled fabric may emerge after drying. These techniques are familiar to those skilled in the art. A tenter-frame can be used to provide fabric overfeed during drying. The objective of the drying step can be to dry the fabric without the high temperatures that can also heatset the fabric and cause thermomigration of dye molecules from the interior of the 2GT polyester and spandex fibers to the surface of said fibers. To enhanced dye washfastness ratings, the fabric may be heated, until dry, at a temperature of about 130 degrees C. or less, and typically at a temperature between about 120 and about 125 degrees C.
[0054] The knit 2GT polyester-spandex fabric can have good dye washfastness ratings, as well as physical properties that are commercially useful. For example, the product of this process has fabric stain ratings typically in the range of 3.5 to 5 with exception at about 3.0. The fabrics can have commercially-useful physical properties as follows:
Basis weight in the range of about 160 to about 330 g/m2 Elongation in the warp (length) direction of about 80% or more, and preferably from about 80% to about 130% Shrinkage after washing and drying of about 3% or less and typically less than 3% in both length and width.
The process provides this combination of product with the flexibility to use azo and anthraquinone dyes of deep color shades (including high energy dyes).
EXAMPLES
[0058] The following examples are to be regarded as illustrative in nature and not as restrictive.
[0059] Fabric Knitting and Finishing
[0060] Circular knit elastic single jersey fabrics with bare spandex plated with hard yarn for the examples were knit on a Pai Lung Circular Knitting Machine, Model PL-XS3B/C, with 26 inches cylinder diameter, 24 gauge, and 78 yarn feed positions. The machine was operated at 26 rpm.
[0061] The broken end detector in each spandex feed path (see FIG. 2 ) was either adjusted to reduce sensitivity to yarn tension, or removed from the machines for these examples. The broken end detector was a type that contacted the yarn, and therefore induced tension in the spandex.
[0062] The spandex feed tension was measured between the spandex supply package 36 and the roller guide 37 ( FIG. 2 ) with a Zivy digital tension meter, model number, EN-10. For examples of the invention, the spandex feed tensions were maintained at 1 gram or less for 20 and 30-denier spandex. These tensions were sufficiently high for reliable and continuous feeding of the spandex yarn to the knitting needles, and sufficiently low to draft the spandex only about 2.5× or less. We found that when the feed tensions were too low, the spandex yarn wrapped around the roller guides at the supply package and could not be reliably fed to the circular knitting machine.
[0063] All the knitted fabrics were scoured, dyed and dried per the process 60 in FIG. 5 .
[0064] Fabrics were scoured in a jet dye machine (Tong Geng Enterprise Co. Ltd. TGRU-HAF-1-30) at 90° C. for 20 minutes. The concentration of ingredients in the scouring solution, per liter of water, were as follows: 0.75 g/l Humectol Lys (Clariant), 2.0 g/l Na2CO3 (Sesoda), 0.5 g/l Imacol S (Clariant), 0.5 g/l Antimussol HT2S (Clariant), and 0.5g/l Glacial acetic acid.
[0065] The fabrics were dyed individually, and, the same machine was used for each example. For examples A1, B5, C9, and D13, Brilliant Red-SR GL (Clariant), a middle energy dye type SE (or C), was used at a 3.5% level based on the weight of fabric (OWF). For examples A2, B6, C10, and D14, Rubine SWF (Clariant) at 3.0% OWF and Black SWF (Clariant) at 1.5% OWF were used. Both these are middle energy dyes, type SE (or C). For examples A3, B7, C11, and D15, Dark Blue RD2RE 300% (Clariant), a high energy dye type S (or D), was used at 3.5% OWF. For examples, A4, B8, C12, and D16, Black RD-3GE 300% (Clariant), a high energy dye type S (or D), was used at 3.57% OWF. The liquor ratio was 1:12. The concentrations of ingredients in the dye liquor for each fabric, per liter of water, were as follows: dye as given above, 0.5 g/l Imacol S (Clariant), and 2.0 g/l Sandacid PB (Clariant). The dyebath pH was 4.12. The fabric cycle time was 51 seconds/cycle. The bath temperature was raised from room Temperature to 130° C. at the rate of 1° C. per minute. The process was operated at 130° C. for 30 minutes, followed by cool down to 70° C. at the cooldown rate of 1° C. per minute. The dyebath was then drained and the machine recharged with cool water, followed by rinsing of the fabric for 10 minutes. The water was subsequently drained to prepare the fabric for reduction clearing.
[0066] The fabric was subsequently reduction cleared in the jet dye machine in a clearing solution at 85° C. for 30 minutes. The ingredients in the solution, per liter of water, were as follows: 3.0 g/l Eriopon OS (Ciba), 2.0 g/l Na 2 Co 3 (Sesoda), 3.33 ml/l NaOH (45%), 0.5 g/l Antimussol HT2S (Clariant), and 6.0 g/l NaS 2 O 4 . The solution temperature was raised from room temperature to 85° C. at a rate of 1° C. per minute and held there for 30 minutes. The solution was subsequently cooled down to 60° C. at the rate of 1° C. per minute, and then drained. Following that, the fabric was neutralized with glacial acetic acid for 10 minutes, then rinsed with clean water for 5 minutes. The wet fabrics were then de-watered by centrifuge, for 8 minutes or until water is removed depending on fabric and diameter and speed of equipment, as per normal practice. For the final step, a lubricant (softener) was padded onto the fabrics in a 77-liter water solution with Sandoperm SEI (Clariant, 1155 g). The fabrics were then dried in a tenter oven at about 130° C. for about 30 seconds, at about 50% fabric overfeed.
[0067] The above procedure and additives will be familiar to those experienced in the art of textile manufacturing and circular knitting of single jersey knit fabrics.
[0000] Analytical Methods
[0068] Stain Ratings—Stain ratings ranging from 1.0 to 5.0 are determined by grading white multifiber fabric samples that are stained when included in an accelerated wash test. The wash test conditions and stain rating methodologies are those defined by the American Association of Textile Chemists and Colorists (AATCC) in AATCC Test Method 61-1996-2A. This method is herein incorporated in its entirety by reference.
[0069] Spandex Draft—The following procedure, conducted in an environment at 20° C. and 65% relative humidity, is used to measure the spandex drafts in the Examples.
De-knit (unravel) a yarn sample of 200 stitches (needles) from a single course, and separate the spandex and hard yarns of this sample. A longer sample is de-knit, but the 200 stitches are marked at beginning and end. Hang each sample (spandex or hard yarn) freely by attaching one end onto a meter stick with one marking at the top of the stick. Attach a weight to each sample (0.1 g/denier for hard yarn, 0.001 g/denier for spandex). Lower the weight slowly, allowing the weight to be applied to the end of the yarn sample without impact. Record the length measured between the marks. Repeat the measurements for 5 samples each of spandex and hard yarn. Calculate the average spandex draft according to the following formula:
Draft=(Length of hard yarn between marks)÷(Length of spandex yarn between marks).
[0074] If the fabric has been heat set, as in the prior art, it is usually not possible to measure the in-fabric spandex draft. This is because the high temperatures needed for spandex heat setting will soften the spandex yarn surface and the bare spandex will tack to itself at stitch crossover points 16 in the fabric ( FIG. 1 ). Because of such multiple tack points, one cannot de-knit fabric courses and extract yarn samples.
[0075] Fabric Weight—Knit Fabric samples are die-punched with a 10 cm diameter die. Each cut-out knit fabric sample is weighed in grams. The “fabric weight” is then calculated as grams/square meters.
[0076] Spandex Fiber Content—Knit fabrics are de-knit manually. The spandex is separated from the companion hard yarn and weighed with a precision laboratory balance or torsion balance. The spandex content is expressed as the percentage of spandex weight to fabric weight.
[0077] Fabric Elongation—The elongation is measured in the warp direction only. Three fabric specimens are used to ensure consistency of results. Fabric specimens of known length are mounted onto a static extension tester, and weights representing loads of 4 Newtons per centimeter of length are attached to the specimens. The specimens are exercised by hand for three cycles and then allowed to hang free. The extended lengths of the weighted specimens are then recorded, and the fabric elongation is calculated.
[0078] Shrinkage—Two specimens, each of 60×60 centimeters, are taken from the knit fabric. Three size marks are drawn near each edge of the fabric square, and the distances between the marks are noted. The specimens are then sequentially machine washed 3 times in a 12-minute washing machine cycle at 40° C. water temperature and air dried on a table in a laboratory environment. The distances between the size marks are then re-measured to calculate the amount of shrinkage.
[0079] Face Curl—A 4-inch×4-inch (10.16 cm×10.16 cm) square specimen is cut from the knit fabric. A dot is placed in the center of the square, and an ‘X’ is drawn with the dot as the center of the ‘X’. The legs of the ‘X’ are 2 (5.08 cm) inches long and in line with the outside corners of the square. The X is carefully cut with a knife, and then the fabric face curls of two of the internal points created by the cut are measured immediately and again in two minutes, and averaged. If the fabric points curl completely in a 360° circle, the curl is rated as 1.0; if it curls only 180°, the curl is rated ½; and so on.
EXAMPLES 1-16
[0080] Table 1 below sets forth the knitting conditions for the example knit fabrics. Lycra® types 169B and 162C were used for the spandex feeds (commercially available from Invista S. á. r. l. of Wichita, Kans. and Wilmington, Del.). Lycra® deniers were 40 and 30, or 44 dtex and 33 dtex, respectively. The stitch length, L, was a machine setting. Spandex feed tensions are listed in grams and 1.00 grams equal 0.98 centiNewtons(cN).
[0081] Table 2 summarizes the major finishing conditions of the fabrics. Include description of the specifics for each group of fabrics. Examples, A1, A2, B5, B6, C9, C10, D13, and D14 were dyed with middle energy dyes otherwise known in the industry as SE (or C) type dyes. Examples A3, A4, B7, B8, C11, C12, D15, and D16 were dyed with high energy dyes otherwise known in the industry as S (or D) type dyes.
TABLE 2 FINISHING CONDITIONS Liquor Heat Set, Jet Dyeing Energy Dye Bath Liquor Temp, ° C., Dry, ° C., Example Dye Type Rating Color Ratio ° C. 45 sec. 120 sec. A1 Disperse Middle, Blue 1:12 130 below SE 130 A2 Disperse Middle, Black 1:12 130 below SE 130 A3 Disperse High, S Red 1:12 130 below 130 A4 Disperse High, S Purple 1:12 130 below 130 B5 Disperse Middle, Blue 1:12 130 170 SE B6 Disperse Middle, Black 1:12 130 170 SE B7 Disperse High, S Red 1:12 130 170 B8 Disperse High, S Purple 1:12 130 170 C9 Disperse Middle, Blue 1:12 130 below SE 130 C10 Disperse Middle, Black 1:12 130 below SE 130 C11 Disperse High, S Red 1:12 130 below 130 C12 Disperse High, S Purple 1:12 130 below 130 D13 Disperse Middle, Blue 1:12 130 170 SE D14 Disperse Middle, Black 1:12 130 170 SE D15 Disperse High, S Red 1:12 130 170 D16 Disperse High, S Purple 1:12 130 170
[0082] Table 3 summarizes key results of the tests finished fabrics.
TABLE 3 FABRIC RESULTS Fabric Lycra ® Stain Lycra ® Basis Maximum spandex Shrinkage Face Curl, Rating Stain Stain Stain Stain Ex- spandex Weight, Length Content in %, Warp Fraction to Rating to Rating to Rating to Rating ample Draft g/m2 Elongation % Fabric, % by Weft of 360° cotton nylon polyester acrylic to wool A1 2.5 298 104 7.2 −1 × −1 0.0 4.5 3.0 4.5 4.5 4.0 A2 2.5 297 101 7.2 −2 × −1 0.0 4.5 3.5 4.5 4.5 4.0 A3 2.5 300 103 7.2 −1 × −1 0.0 4.5 3.5 4.5 4.5 4.5 A4 2.5 298 100 7.2 −2 × −1 0.0 4.5 4.5 4.5 4.5 4.5 B5 3.5 271 102 5.5 −1 × 0 0.0 4.5 2.0 3.0 4.5 3.5 B6 3.5 279 104 5.5 −1 × 0 0.0 4.5 2.5 3.5 4.5 4.0 B7 3.5 279 107 5.5 −1 × 0 0.0 4.0 2.0 4.0 4.5 3.5 B8 3.5 282 108 5.5 −1 × 0 0.0 4.5 2.5 3.5 4.5 4.0 C9 2.5 306 106 9.1 0 × 0 0.0 4.5 3.0 4.5 4.5 4.0 C10 2.5 305 104 9.1 0 × −1 0.0 4.5 3.0 4.5 4.5 4.0 C11 2.5 305 105 9.1 0 × −1 0.0 4.5 4.0 4.5 4.5 4.5 C12 2.5 309 104 9.1 0 × −1 0.0 4.5 4.0 4.5 4.5 4.5 D13 3.5 271 85 6.7 0 × 0 0.0 4.5 3.0 4.5 4.5 4.0 D14 3.5 263 79 6.7 0 × 0 0.0 4.5 2.5 4.0 4.5 4.0 D15 3.5 266 84 6.7 0 × 0 0.0 4.5 2.5 4.5 4.5 4.5 D16 3.5 251 73 6.7 0 × 0 0.0 4.5 3.0 4.0 4.5 4.0
EXAMPLE A1
[0083] The fabric was knit using 150D/288f microdenier 2GT polyester and 33 dtex Lycra® spandex. The draft of the spandex in the fabric was 2.5×. The fabric of Example A1 was dyed with a middle energy, SE-rated dye to a blue shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example A1 is 298 g/m 2 with acceptable shrinkage. Stain rating to nylon is 3.0.
EXAMPLE A2
[0084] The fabric of Example A1 was dyed with a middle energy, SE-rated dye to a black shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example A2 is 297 g/m 2 with acceptable shrinkage. Stain rating to nylon is 3.5.
EXAMPLE A3
[0085] The fabric of Example A1 was dyed with a high energy, S-rated dye to a red shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example A3 is 300 g/m 2 with acceptable shrinkage. Stain rating to nylon is 3.5.
EXAMPLE A4
[0086] The fabric of Example A1 was dyed with a high energy, S-rated dye to a purple shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example A4 is 298 g/m 2 with acceptable shrinkage. Stain rating to nylon is 4.5.
EXAMPLE B5
[0087] The fabric was knit using 150D/288f microdenier 2GT polyester and 33 dtex Lycra® spandex. The draft of the spandex in the fabric was 3.5×. The fabric of Example B5 was dyed with a middle energy, SE-rated dye to a blue shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example B5 is 271 g/m 2 with acceptable shrinkage. Stain rating to nylon is 2.
EXAMPLE B6
[0088] The fabric of example B5 was dyed with a middle energy, SE-rated dye to a black shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example B6 is 279 g/m 2 with acceptable shrinkage. Stain rating to nylon is 2.5.
EXAMPLE B7
[0089] The fabric of example B5 was dyed with a high energy, S-rated dye to a red shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example B7 is 279 g/m 2 with acceptable shrinkage. Stain rating to nylon is 2.
EXAMPLE B8
[0090] The fabric of example B5 was dyed with a high energy, S-rated dye to a purple shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for
EXAMPLE B8 is 282 g/m 2 with acceptable shrinkage. Stain rating to nylon is 2.5.
EXAMPLE C9
[0091] The fabric was knit using 150D/48f 2GT polyester and 44 dtex Lycra® spandex. The draft of the spandex in the fabric was 2.5×. The fabric of Example C9 was dyed with a middle energy, SE-rated dye to a blue shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example C9 is 306 g/m 2 with acceptable shrinkage. Stain rating to nylon is 3.0.
EXAMPLE C10
[0092] The fabric of Example C9 was dyed with a middle energy, SE-rated dye to a black shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example C10 is 305 g/m 2 with acceptable shrinkage. Stain rating to nylon is 3.0.
EXAMPLE C11
[0093] The fabric of Example C9 was dyed with a high energy, S-rated dye to a red shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example C11 is 305 g/m 2 with acceptable shrinkage. Stain rating to nylon is 4.0.
EXAMPLE C12
[0094] The fabric of Example C9 was dyed with a high energy, S-rated dye to a purple shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example C12 is 309 g/m 2 with acceptable shrinkage. Stain rating to nylon is 4.0.
EXAMPLE D13
[0095] The fabric was knit using 150D/48f 2GT polyester and 44 dtex Lycra® spandex. The draft of the spandex in the fabric was 3.3×. The fabric was dyed with a middle energy, SE-rated dye to a blue shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example D13 is 271 g/m 2 with acceptable shrinkage. Stain rating to nylon is 3.0.
EXAMPLE D14
[0096] The fabric of example D13 was dyed with a middle energy, SE-rated dye to a black shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example D14 is 263 g/m 2 with acceptable shrinkage. Stain rating to nylon is 2.5.
EXAMPLE D15
[0097] The fabric of example D13 was dyed with a high energy, S-rated dye to a red shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example D15 is 266 g/m 2 with acceptable shrinkage. Stain rating to nylon is 2.5.
EXAMPLE D16
[0098] The fabric of example D13 was dyed with a high energy, S-rated dye to a purple shade and finished according to the process schematically shown in FIG. 5 . The fabric basis weight for Example D16 is 251 g/m 2 with acceptable shrinkage. Stain rating to nylon is 3.0. | The invention includes a dyed knit, elastic fabric comprising polyethylene terephthalate and spandex. The fabric has staining grade numbers of 4.0 or higher, as measured by staining of multifiber test fabrics in AATCC Test Method 61-1996-2A, and is dyed with disperse dyes comprising azo or anthraquinone molecular groups. The invention further includes a method for making the knit fabric. | 3 |
FIELD OF THE INVENTION
This invention relates to novel beta-lactam compounds which demonstrate potent elastase inhibition activity.
BACKGROUND OF THE INVENTION
Human polymorphonuclear leukocyte elastase is the enzyme primarily responsible for the destruction of lung tissue observed in pulmonary emphysema. In addition to emphysema, human leukocyte elastase is a suspected contributor to the pathogensis of disease states such as adult respiratory distress syndrome and rheumatoid arthritis.
Proteases are an important group of enzymes in the class of peptide-bond cleaving enzymes. These enzymes are essential for a variety of normal biological activities, including digestion, formation and dissolution of blood clots, the formation of active forms of hormones, the immune reaction to foreign cells and organisms, and in the body's response to various pathological conditions, such as pulmonary emphysema and rheumatoid arthritis.
Elastase, one of the proteases, is an enzyme able to hydrolyze elastin, a component of connective tissue. This property is not shared by the bulk of the proteases present in the body. Elastase acts on a protein's nonterminal bonds which are adjacent to an aliphatic amino acid. Of particular interest is neutrophil elastase, which exhibits a broad spectrum of activity against natural connective tissue substrates. In particular, the elastase of the granulocyte is important because granulocytes are participants in acute inflammation and in acute exacerbation of chronic forms of inflammation which characterize many major inflammatory diseases.
Proteases from granulocytes and macrophages are reported to be responsible for the chronic tissue destruction mechanisms associated with such inflammatory diseases as pulmonary emphysema, rheumatoid arthritis, bronchial inflammation, osteo arthritis, spondylitis, lupus, psoriasis, and acute respiratory distress syndrome. Proteases can be inactivated by inhibitors which bind tightly to enzymes to block their active sites. Naturally occuring protease inhibitors are part of the body's defense mechanism which are vital to the maintence of a state of well being. Without such a natural defense mechanism, the proteases would destroy any protein with which they came in contact. Naturally occuring enzyme inhibitors have been shown to have appropriate configurations which allow them to bind tightly to the enzymes. Thus, specific and selective inhibitors of the proteases are excellent candidates for potent anti-inflammatory agents useful in the treatment of the above conditions.
Proteases from granulocytes, leukocytes and macrophages are participants in a three-stage chain of events which occur during the progression of an inflammatory condition. During the first stage a rapid production of prostaglandins (PG) and related compounds synthesized from arachidonic acid occurs. The evidence suggests that protease inhibitors prevent PG production. During the second stage of progression of an inflammatory condition, a change in vascular permeability occurs, which causes a leakage of fluid into the inflammed site, which results in edema. The extent of edema is generally used as a means for measuring the progression of the inflammation. The process can be inhibited by various synthetic proteases inhibitors. The third stage of progression of an inflammatory condition is characterized by an appearance and/or presence of lymphoid cells, especially macrophages and polymorphonuclear leukocytes (PMN). It has been shown that a variety of proteases and released from the macrophages and PMN, thus indicating that the proteases play an important role in inflammation.
Rheumatoid arthritis is a degenerative inflammatory condition characterized by a progressive destruction of articular cartilage both on the free surface bordering the joint space and at the erosion front built up by synovial tissue toward the cartilage. This destructive process has been attributed to the protein-cutting enzyme elastase which is a neutral protease present in human granulocytes. This conclusion si supported by observations that there is an accumulation of granulocytes at the cartilage/pannus junction in rheumatoid arthritis and by recent investigation of the mechanical behavior of cartilage in response to attack by purified elastase which has shown the direct participation of granulocyte enzymes, especially elastase, in rheumatoid cartilage destruction.
The elastase inhibitory properties of several beta-lactam compounds is known in the art. U.S. Pat. No. 4,465,687 discloses N-acyl-derivatives of thienamycin esters and their use as anti-inflamatory agents.
U.S. Pat. No. 4,493,839 discloses derivatives of 1-carbapenem-3-carboxylic esters and their use as anti-inflammatory agents.
U.S. Pat. No. 4,495,197 discloses derivatives of N-carboxyl-thienamycin esters and analogs thereof and their use as anti-inflammatory agents.
U.S. Pat. No. 4,547,371 discloses substituted cephalosporin sulfones and their use as anti-inflammatory and anti-degenerative agents.
European Patent 124,081 discloses 3-substituted-3-cephem-4-carboxylate 1,1-dioxides and their use as anti-inflammatory and anti-degenerative agents.
SUMMARY OF THE INVENTION
According to the invention, beta-lactam compounds of the general formulae I, II and III are provided: ##STR2## wherein X and Y are each --S-- or --CH 2 --, with at least one of X and Y being --S--; or alternatively, X is --SO-- or --SO 2 -- and Y is --CH 2 --; R 1 is selected from the group consisting of hydrogen, tri(lower alkyl)silyl, --COOR" and -CONHR"', wherein R" and R"' are each selected from the group consisting of lower alkyl and phenyl(lower alkyl), and may be the same or different: R 3 is selected from the group consisting of hydrogen, lower alkyl and (lower alkyl)oxy: one of B and D is selected from the group consisting of (lower alkyl)oxycarbonyl, (lower alkenyl)oxycarbonyl, allyloxycarbonyl and phenyl(lower alkyl)oxycarbonyl; and the other of B and D is one selected from the group consisting of hydrogen and lower alkyl.
The invention also provides pharmaceutical compositions comprising a compound of the general formula I, II, or III, together with a pharmaceutically acceptable diluent or carrier.
The invention further provides a compound of the general formula I, II, or III for use in treating pulmonary emphysema and rheumatoid arthritis in humans.
The invention still further provides a method of treatment of adult respiratory distress syndrome and related inflammatory conditions, especially pulmonary emphysema, and for treatment of rheumatoid arthritis comprising administering an effective amount of a compound of the general formula I, II, or III to a human being.
DETAILED DESCRIPTION OF THE INVENTION
As used herein, terms such as alkyl, alkenyl, etc., include both straight chain and branched groups, except where expressly indicated to the contrary. The term lower prefixed to any of the above terms is used to denote groups of the described type containing from 1 to 6 carbon atoms, i.e. C 1 -C 6 .
In the compounds of the general formulae I, II and III, R 1 is preferably hydrogen, (t-butyl)dimethylsilyl, t-butoxycarbonyl, benzyloxycarbonyl or benzylaminocarbonyl: R 2 is preferably methyl: B is preferably t-butoxycarbonyl: and D is preferably hydrogen.
Compounds demonstrating the greatest activity, and hence which are most preferred, are those wherein both X and Y are --S--, and wherein the other substituent groups are selected from among the preferred choices indicated above.
The compounds of general formulae I, II and III are prepared by several synthesis routes according to the invention.
For example, a compound (ID) of the general formulae I wherein both X and Y are --S--: R 1 is hydrogen; R 2 is methyl B is t-butyoxycarbonyl and D is hydrogen may be prepared as follows: ##STR3##
The intermediate of formula IA is prepared by reacting a strong base such as lithium bis(trimethylsilyl)amide, together with tertiary butyl acetate, carbon disulfide and tributyl tin chloride in a non-protic solvent such as tetrahydrofuran (THF) and under an inert atmosphere. This reaction is typically carried out at a low temperature, for example, about -75° C. to -80° C., for the next step.
The resulting intermediate of formula IA is reacted with 3R, 4R-4-acetoxy-3-[1R-(dimethyl-t-butyl-siloxy)ethyl]-2-azetidinone, a strong base such as sodium hydride and a non-protic solvent such as THF under an inert atmosphere to produce the intermediate of formula IB. This reaction is typically carried out at a temperature of around -10° C.
The intermediate of formula IB is allowed to react with n-chlorosuccinimide (NCS) and a base such as diisopropylethylamine in a non-protic solvent such as dichloromethane and under an inert atmosphere to produce the intermediate of formula IC. This reaction is typically carried out at a low temperature of around 0° C. to -20° C. A certain amount of the less preferred isomer in which B is hydrogen and D is t-butoxycarbonyl will also be formed. The selectivity for the preferred isomer IC is increased at lower reaction temperatures.
Finally, the intermediate of formula IC is converted in the presence of a non-protic solvent such as THF, acetic acid and tetrabutylammonium fluoride (TBAF) and under an inert atmosphere to the compound of formula ID.
Compounds identical to ID except for B being a different ester group may be prepared by preparing and utilizing the appropriate intermediate IA.
Other products of the general formula I and products of the general formula II are obtainable by the further reaction of the final product of the foregoing reaction synthesis with an appropriate electrophile in the presence of a strong base, such as dimethylaminopyridine, in accordance with the following: ##STR4## The resulting compounds of formulae I and II may be separated by silica gel chromatography.
The compound of formula I produced depends on the nature of the electrophile, as shown in the accompanying Table 1.
TABLE 1______________________________________Electrophile R.sup.1______________________________________ ##STR5## ##STR6## ##STR7## ##STR8## ##STR9## ##STR10##______________________________________
Compounds of the general formulae I and II wherein one of B and D is lower alkyl rather than hydrogen may be prepared by the synthesis routes described above with the use of an appropriate t-butyl ester other than t-butyl acetate.
A compound (IF) of general formula I, wherein X is --CH 2 -- and Y is --S--; R 1 is hydrogen R 2 is methyl B is t-butoxycarbonyl and D is hydrogen may be prepared as follows: ##STR11##
The conversion of intermediate IVA to intermediate IVB is carried out in the presence of a strong acid such a trifluoroacetic acid (TFA) and bubbling H 2 S at about 0° C., in a polar solvent such a dimethylformamide (DMF). Following silica gel chromatography, the compound IVB is allowed to react with n-chlorosuccinimide (NCS) and a base such as diisopropylethylamine in a non-protic solvent such as dichloromethane and under an inert atmosphere to produce a mixture of a major proportion of compound IVC and a minor proportion of compound IVD.
The two compounds of formulae IVC and IVD are stereoisomers which are reversibly convertible by photolysis.
The compounds of formulae IVC and IVD may be desilylated in the same manner as described earlier herein and, if desired, subsequently subjected to electrophillic substitution, also as described above.
Compounds (IG, IH) of general formula I, wherein X is --S-- and Y is --CH 2 --; R 1 is hydrogen; R 2 is methyl and, in the case of (IG), B is t-butoxycarbonyl and D is hydrogen and, in the case of (IH), B and D are vice versa, may be prepared according to the following reaction scheme: ##STR12##
The first step of this synthesis is the alkylation of VA by a haloallylacetate, followed by palladium-catalyzed deallylation to yield VB. Compound VB is converted to compound VC under standard detritylation conditions (e.g. using silver trifluoroacetate and pyridine, followed by H 2 S treatment). Conversion of VC to thiolactone VD is carried out using dicyclohexylcarbodiimide (DCC) in an aprotic solvent such as dichloromethane. Standard Wittig olefination is used to generate the stereoisomeric mixture of compounds VE and VF. This stereoisomeric mixture may then be disilylated under standard conditions and the resulting mixture of compounds IG and IH separated by silica gel chromatography. It is, however, preferred to first separate VG and VF by silica gel chromatograply and then desilylate each stereoisomer separately.
It is understood that compounds of general formula III may be prepared by conventional synthetic routes from the appropriate 3-substituted-4-acetoxy-azetidin-2-ones.
Still other compounds of interest are obtainable by treating those compounds of formulae I, II, and III of the invention in which X is --S-- and Y is --CH 2 -- to oxygenate the thia group X.
Thus, for example, ##STR13##
Representative compounds of the general formulae I, II and III, prepared in accordance with the invention, are listed in Table 2:
TABLE 2__________________________________________________________________________ ##STR14## ##STR15## ##STR16##FormulaR.sup.1 R.sup.2 R.sup.3 X Y B D__________________________________________________________________________I H CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub. HI H CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub.3 CH.sub.3I H CH.sub.3 -- S S H CO.sub.2 C(CH.sub.3).su b.3I H CH.sub.3 -- S S H ##STR17##I H CH.sub.3 -- S S CO.sub.2 (CH.sub.2)CHCH.sub.2 HI H CH.sub.3 -- S S ##STR18## HI H CH.sub.3 -- S S ##STR19## H ##STR20## CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub.3 HI ##STR21## CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub.3 HI ##STR22## CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub.3 HI ##STR23## CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub.3 HI (CH.sub.3).sub.3 COCO CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub.3 HI (CH.sub.3).sub.3 C(CH.sub.3).sub.2 Si CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub.3 HI H CH.sub.3 -- CH.sub.2 S CO.sub.2 C(CH.sub.3).sub.3 HI H CH.sub.3 -- CH.sub.2 S H CO.sub.2 C(CH.sub.3).su b.3I ##STR24## CH.sub.3 -- CH.sub.2 S CO.sub.2 C(CH.sub.3).sub.3 HI ##STR25## CH.sub.3 -- CH.sub.2 S CO.sub.2 C(CH.sub.3).sub.3 HI (CH.sub.3).sub.3 C(CH.sub.3).sub.2 Si CH.sub.3 -- CH.sub.2 S CO.sub.2 C(CH.sub.3).sub.3 HI (CH.sub.3).sub.3 C(CH.sub.3).sub.2 Si CH.sub.3 -- CH.sub.2 S H CO.sub.2 C(CH.sub.3).su b.3I H CH.sub.3 -- S CH.sub.2 CO.sub.2 C(CH.sub.3).sub.3 HI H CH.sub.3 -- S CH.sub.2 H CO.sub.2 C(CH.sub.3).su b.3I ##STR26## CH.sub.3 -- S CH.sub.2 CO.sub.2 C(CH.sub.3).sub.3 HI (CH.sub.3).sub.3 C(CH.sub.3).sub.2 Si CH.sub.3 -- S CH.sub.2 H CO.sub.2 C(CH.sub.3).su b.3I (CH.sub.3).sub.3 C(CH.sub.3).sub.2 Si CH.sub.3 -- S CH.sub.2 CO.sub.2 C(CH.sub.3).sub.3 HI ##STR27## CH.sub.3 -- SO CH.sub.2 CO.sub.2 C(CH.sub.3).sub.3 HI ##STR28## CH.sub.3 -- SO.sub.2 CH.sub.2 CO.sub.2 C(CH.sub.3).sub.3 HI H CH.sub.3 -- SO.sub.2 CH.sub.2 CO.sub.2 C(CH.sub.3).sub.3 HII -- CH.sub.3 -- S S CO.sub.2 C(CH.sub.3).sub.3 HII -- CH.sub.3 -- CH.sub.2 S CO.sub.2 C(CH.sub.3).sub.3 HIII -- -- H S S CO.sub.2 C(CH.sub.3).sub.3 H__________________________________________________________________________
EXAMPLES
EXAMPLE 1
Preparation of acetic acid, [6-ethylidene-7-oxo-2,4-dithia-1-azabicyclo[3.2.0]hept-3-ylidene]-, 1,1-dimethylethyl[R-(E,E)]
Under a nitrogen atmosphere, 20 mg of ##STR29## were dissolved in 1.5 ml methylene chloride. This solution was cooled to -5° C. using a wet ice/acetone bath and 16 mgs of 4-dimethylamino pyridine were added, followed by addition of 0.0188 ml of benzyl chloroformate. The resulting mixture was stirred at -5° C. for 1 hr., at which time an additional 16 mg of 4-dimethylamino pyridine and 0.188 ml of benzyl chloroformate were added. This sequence was repeated two more times resulting in dissappearance of the starting material as monitored by thin-layer chromatography. The reaction mixture was quenched in 75 mls ethylacetate and 35 ml H 2 O, the ethylacetate layer was separated, washed twice with H 2 O, dried over Na 2 SO 4 , filtered and concentrated to yield a mixture of desired products. Separation and purification were achieved by column chromatography (silica gel/9:1 hexane:ethylacetate(EtOAc)) to yield 2-3 mgs of a 1:1 mixture of ##STR30## and 9 mgs of ##STR31##
EXAMPLE 2
Preparation of acetic acid, [6-ethylidene-7-oxo-2-thia-1-azabicyclo[3.2.0]hept-3-ylidene],-1,1-dimethylethyl ester [R-(E,E)] and acetic acid, [7-oxo-6-[1-(((phenylmethoxy)carbonyl)oxy)ethyl]-2-thia-1-azabicyclo[3.2.0]hept-3-ylidene]-1,1-dimethylester [5R-[3R, 5α, 6α (R))
Using the procedure described in J. of Antibiotics 36, p. 1034-39 (1983), a sufficient amount of compound IVA was prepared. ##STR32##
Under an N 2 atmosphere, 2.53 g of IVA were dissolved and combined with 12 mls Aldrich dry DHF. The mixture was cooled to 0° C. in an ice bath, and 0.45 mls of TFA was added over a 1 min. period, with stirring for about 1 min. The ice bath was removed and H 2 S was bubbled in for 3 min. The mixture was stirred 5 min, quenched in 150 mls Et 2 O/75 mls H 2 O. The Et 2 O layer was separated and, the aqueous layer was extracted with 75 ml fresh Et 2 O. The Et 2 O extracts were combined, washed three times with H 2 O, concentrated, and chromotographed on silica gel using 2:1 hexane:EtOAc to yield 0.82 g of pale yellow oil (IVB), which was NMR consistent with the desired structure.
Under an N 2 atmosphere, 0.125 g of ##STR33## was dissolved in 20 ml CH 2 Cl 2 . The mixture was cooled to -20° C., 41 mg NCS were added, then 0.054 ml diisopropylethylamine in 5 cc CH 2 Cl 2 was added dropwise. At the end of the addition, the mixture was checked by thin layer chromatography for disappearance of starting material, then washed three times with H 2 O, once with brine, dried, concentrated, and chromotographed using (silica gel/9:1 hexane:EtOAc) to yield 5 mgs of lp isomer and 63 mg mp isomer. NMR data, H & C13 analysis were consistent with the desired structure. Based on NOE experiments, the major isomer was assigned the structure ##STR34##
60 ml CCl 4 were degassed by bubbling N 2 through for 10-15 min, then the material was illuminated with a sun lamp for 9 hrs in a flask equipped with a reflux condensor. Product was isolated by column chromotography using 6:1 hexane:EtOAc.
Under a nitrogen atmosphere, 28.5 mgs of ##STR35## were dissolved in 8 ml of dichloromethane. This solution was cooled down to -5° C. and 0.122 g of 4-dimethylamino pyridine was added, followed by addition of 0.144 ml benzylchloroformate. The rate of reaction, as monitored by thin layer chromatography (TLC), was very slow at -5° C. The reaction was allowed to warm to room temperature to increase the rate of reaction. An additional 0.122 g of 4-dimethylamino pyridine and 0.144 ml benzylchloroformate were added to the reation mixture. This sequence was repeated a total of four times at 1 hour intervals. Each time before addition, the reaction was cooled down to 5° C. then allowed to come to room temperature during the 1 hr. of stirring which preceeded the next addition. After the last addition TLC monitoring indicated only traces of starting material present. The reaction mixture was diluted with 75 ml ethylacetate, washed six times with H 2 O, twice with 10 ml lN HCL, four times with 25 ml H.sub. 2 O, once with brine, dried over Na 2 SO 4 , filtered, concentrated, and the products purified and separated by column chromatography (silica gel/9:1 hexane:EtOAc) to yield 1 mg of a mixture of olefins ##STR36## and 28.5 mgs of ##STR37##
EXAMPLE 3
Preparation of acetic acid, [6-[1-[[(phenylmethoxy)carbonyl]oxy]ethyl]-7-oxo-2,4-dithia-1-azabicyclo[3.2.0]hept-3-ylidene]-,1,1-dimethyl ethyl ester, [5R-[3E, 5α, 6α (R*)]]
Under an N 2 atmosphere, in a flask wrapped in aluminum foil to keep out light, 15 g of compound VB were dissolved with 50ml CH 2 Cl 2 , and stirred int. solution. To this was added 18 mls sodium ethyl hexanoic acid ethyl acetate (1 eq), then a mixture of 2 g of triphenylphosphine and 2 g of tetrakis(triphenylphosphine)palladium complex was added in one portion and allowed to stand as is. The mixture was TLC'd after 30 min, and showed some starting material remaining. To this was then added 0.4 g each of triphenylphosphine and tetrakis(triphenylphosphine)palladium complex. The mixture was allowed to stand 45 min more, then was quenched in 150 ml EtOAc and 50 ml 1N HCl, Ph 2.0. The organic layer was shaken and separated, washed once with H 2 O, dried and concentrated to yield solids which were triturated with 125 mls Et 2 O, filtered washed well with Et 2 O and dried to yield 9.2 g of solids having an NMR consistent the with desired structure.
Under an N 2 atmosphere, in equipment wrapped in aluminum foil for the purposes of keeping out light, 7.47 g of a starting trityl compound of the formula VC was dissolved in 75 mls of dichloromethane and 1.6 ml of methanol. To this mixture was added 4.3 ml pyridine. The resulting solution was cooled down to 0° C. and 5.85 g of ##STR38## in 25 ml dichloromethane with enough methanol added to solubolize ##STR39## was added dropwise. TLC performed 10 min. after completion of the addition indicated the dissappearance of starting material. The reaction was diluted to 125 mls with dichloromethane and washed once with 75 ml lN HCL. The resulting suspension was filtered through a sintered glass funnel to yield 7.3 g of gray solids, after washing well with dichloromethane followed by hexane and air drying.
Under an N 2 atmosphere, these solids were suspended in 175 ml fresh CH 2 Cl 2 amd cooled to 5° C. and with rapid stirring. H 2 S gas was bubbled through this suspension for 5 minutes, after which cooling was removed and the reaction mixture was stirred for 1 hr and 45 min. The reaction was then degassed by bubbling N 2 through, then filtered to remove the black gummy solids. The filtrates were dried over Na 2 SO 4 , filtered to remove Na 2 SO 4 , then cooled down to -30° C. and 2.74 g of dicyclohexylcarbodimide in 25 mls of CH 2 Cl 2 were added over a 5 min period. After the addition was complete, cooling was removed, the reaction was allowed to come to room temperature and was stirred for 1.5 hrs. Upon completion of stirring, the reaction was concentrated to 1/2 volume, the dicyclohexylurea was removed by filtration and the filtrates were chromatographed (silica gel/9:1 hexane:EtOAc) to yield 1.21 g of product of formula VD. ##STR40##
1.51 g of compound VD were combined with 1.88 g of (triphenyl)P=CHCO 2 C(CH 3 ) 3 and 15 ml of benzene and heated at gentle reflux for 6 hours. The reaction was then concentrated and chromatographed (silica ge[/4:1 hexane:EtOAc) to yield 0.34 g of compound VE and 0.3 g of compound VF. Then under an N 2 atmosphere, 0.28 g of compound VD were dissolved in 5 ml of tetrahydrofuran and, 0.44 ml acetic acid and 2.1 ml of 1 molar tetrabutyl ammonium fluoride in tetrahydrofuran were added and the reaction mixture stirred at ambient temperature for 18 hrs. The reaction was worked up by diluting to 75 ml with ethyl acetate, washing three times with H 2 O, once with brine, once with H 2 O, once with brine, drying over Na 2 SO 4 , filtering, concentrating and chromatographing (silica gel/1:1 hexane:EtOAc) to yield 0.181 g of product. ##STR41## Following the procedure of Example 2, 80 mgs of ##STR42## was converted to 0.11 g of the desired compound (I) wherein X and Y are both --S--, R 1 is phenylmethyloxycarbonyl, R 2 is methyl, B is t-butoxy and D is hydrogen: ##STR43##
Oxidation Procedure
Under an N 2 atmosphere, 21 mg of the above form of compound I were dissolved in 1 ml of dichloromethane. The solution was cooled to 5° C. and 10 mg of 85% 3-chloroperoxybenzoic acid were added and the reaction allowed to stir 70 min. at which time thin layer chromatography indicated the presence of the two sulfoxides and just traces of starting material. The reaction was diluted with 25 mls ethyl acetate, and 10 ml H 2 O, and enough Na bisulfite was added to give a negative test for peroxides using starch iodide test paper. The ethyl acetate layer was separated, washed three times with H 2 O, once with brine, dried over Na 2 SO 4 , filtered, concentrated and chromatographed (silica gel/1:1 hexane:EtOAc) to yield 5.6 mgs. of the less polar isomer and 6.8 mgs. of the more polar isomer.
EXAMPLE 4
Preparation of propanoic acid, [2-[6 (1-hydroxyethyl)-7-oxo-2,4-dithia-1-azabicyclo [3.2 0] hept-3-ylidene]-,1,1-dimethylethyl ester, [5S-[3Z, 5α, 6α (R*)]]
120 ml of lM LiN(Si(CH 3 ) 3 ) 2 was added to a round bottom flask under nitrogen atmosphere and cooled down to -78° C. 16.2 ml (0.12 mol) of t-butyl acetate was added at such a rate as to maintain a temperature of -70° C. The mixture was allowed to stand at -70° C. for 10 min., after which 24 ml CS 2 were added. The mixture turned red and its temperature increased to -30° C. The mixture was then cooled back down to -70° C. and stirred for 10 min., then allowed to warm up to 0° C. and was finally cooled back down to -70° C. The mixture thickened. 16.25 ml (0.06 mol) of tributyltin chloride were added at such a rate so that the temperature remained at less than or equal to -60° C. The mixture then became clear and most of the red color disappeared. The mixture was then allowed to stand for 20 min. after which it was quenched with excess acetic acid in tetrahydrofuran at -60° C. The reaction mixture was added to 1.2 1 hexane and 600 ml water were then added. The hexane layer was then separated and washed 5 times with 600 ml water, once with 600 ml brine, dried, and concentrated in vacuo to yield 29.5 g of a light orange oil of formula IA ##STR44##
The above product (ca 0.061 mol) was combined with 150 ml of dry tetrahydrofuran in a round bottom flask under nitrogen atmosphere and stirred into solution. The solution was cooled-down to -10° C. and 2.88 g of 50% sodium hydride (0.06 mol) was added. The mixture was then allowed to warm-up. After gas evolution ceased and a clear solution was obtained, 13.0 g (0.045 mol) of 3R, 4R-4-acetoxy-3-[1R-(dimethyl-t-butylsiloxy) ethyl]2-azetidinone was added and allowed to stir for 12 hours. The reaction was worked up by quenching in 200 ml lN HCl, and 500 ml ethyl acetate. The etryl acetate layer was then washed 4 times with 200 m water, once with 200 ml brine, dried, and concentrated to yield crude solid. The solid was then titrated with 175 ml hexane, filtered, washed 2 times with 15 al hexane and air dried to yield 8.89 g (47%) of product of formula IB as a pale yellow solid. ##STR45## (More product was obtained by chromatographing the mother liquor.)
9.35 g (0.022 mol) of the above product was dissolved in 225 ml methylene chloride in a round bottom flask under nitrogen atmosphere and stirred into solution. The solution was cooled to -20° C. and 2.96 g (0.022 mol) of N-chlorosuccinimide (NCS) was added. A methylene chloride solution (100 ml) containing 3.89 ml (0.022 mol) of diisopropyl ethylamine was then added to the solution over a 5 min. period. The solution was maintained at -20° C. under constant stirring. Thin layer chromatrography was performed 15 min. after addition of the base and indicated the reaction was complete. The solution was then diluted to 750 ml with methylene chloride, washed twice with 150 ml water, once with 100 ml brine, dried and concentrated and chromatographed on silica gel using 4:1 hexane:EtOAc to yield 8.8 grams (91%) of solids which was a 19:1 mixture of double bond isomers of [6-[1-[[(1,1-dimethylethyl)dimethylsilyl]oxy]ethyl]-7-oxo-2,4-dithia-1-azabicyclo[3.2.0]hept-3-ylidene]-, 1,1-dimethylethyl ester, [5R-[3E, 5α, 6α (R*)]]-acetic acid, according to formula IC ##STR46##
8.8 g (0.021 mol) of the above product was combined with 155 ml tetrahydrofuran in a round bottom flask under nitrogen atmosphere and stirred into solution. 25.5 ml acetic acid was added, followed by 61.4 ml TBAF (tetrabutylammonium fluoride) in lM THF and the reaction was stirred for 20 hrs. resulting in a pale yellow solution. The solution was worked-up in the usual manner, i.e., diluted with 750 ml ethylacetate, washed three times with 100 ml H 2 O, once with 100 1 brine, once with 100 1 H 2 O, once with 100 1 brine, dried over Na 2 SO 4 , filtered, concentrated and triturated with isopropyl ether to give product (4.64 g). An additional 0.53 g was obtained upon chromatography of the mother liquor (50:50 hexane: ethyl acetate), totalling 5.17 g (81%) of propanoic acid, [2-[6-(1-hydroxyethyl)-7-oxo-2,4-dithia-1-azabicyclo [3.2.0]hept-3-ylidene]-, 1,1-diemthyl ethyl ester, [5S-[3Z, 5α, 6α (R*)]] product of formula ID ##STR47##
EXAMPLE 5
Preparation of acetic acid, [7-oxo-6-[1-[[-(1,1-dimethyloxy)carbonyl]oxy]ethyl]-2-thia-1-azabicyclo[3.2.0]hept-3-ylidene]-, 1,1-dimethyl ethyl ester, [5R-[3E, 5α, 6α (R*)]]
15 mg of propanoic acid, [2-[6-(1-hydroxyethyl)-7-oxo-2,4-dithia-1-azabicyclo[3.2.0]hept-3-ylidene]-,1,1-dimethyl ethyl ester, [5X-[3Z,5α)6α(R*)]], prepared according to Example 4 was dissolved in 1.5 ml CDCl 3 in a flask under nitrogen atmosphere and cooled to -5° C. in a mixed ice/acetone bath. 6 mg Dimethylaminopyridine (DMAP) was added followed by 0.06 ml pivaloylchloride and stirred for 30 min. To this was added 12 mg DMAP and 0.12 ml pivaloylchloride, with stirring for a further 30 min. TLC indicated the continued presence of starting material. A further 12 mg DMAP and 0.12 ml pivaloylchloride were added with stirring for a further 30 min. TLC was repeated and indicated the continued presence of a small amount of starting material. A portion of the sample was checked by NMR and showed a ratio of product to starting material of approximately 4:1. The addition of 12 mg DMAP and 0.012 ml pivaloylchloride was repeated one more time. TLC indicated the remaining presence of traces of starting material. The mixture was then diluted to 50 cc with ethyl acetate, washed 3 times with 10 cc water and dried and concentrated in vacuo. Silica gel chromatography using 3:1 hexane: ethyl acetate afforded 16.2 mg product (84%) acetic acid, [7-oxo-6-[1-[[(1,1-dimethyloxy)carbonyl]oxy]ethyl]-2-thia-1-azabicyclo[3.2.0]hept-3-ylidene]-, 1,1-dimethyl ethyl ester, [5R-[3E, 5α, 6α (R*)]].
Protocol
In order to screen compounds prepared according to the present invention for their relative efficacy as elastase inhibitors, the protocol Enzyme Assays for the Inhibition of Human Polymorphonuclear Leukocyte Elastase Via Hydrolysis of N-t-Boc-alanyl-alanylprolylalanine-p-nitroanilide was followed.
This protocol utilizes these reagents:
0.05 M TES (N-tris[hydroxymethyl]methyl-2-aminoethanesulfonic acid) Buffer, pH 7.5;
0.2 mM N-t-Boc alanyl-alanyl-prolyl-alanine-p-nitroanilide (Boc-AAPAN).
The substrate was first prepared by dissolving the solid (m.w. 550) in 10.0 ml dimethylsulfoxide (DMSO). Buffer was then added to attain a final volume of 100 ml.
The protocol also utilizes:
A crude extract of human polymorphonuclear leckocytes (PMN) containing elastase activity; and
inhibitors (cephalosporin esters) to be tested, which were dissolved in DMSO just before use.
The assay procedure followed as part of the protocol was to add from 0.01 to 0.1 ml of DMSO, with or without inhibitor, to 1.0 ml of 0.2 mM Boc-AAPAN, in a cuvette. After mixing, a measurement was taken at 410 mμ to detect any spontaneous hydrolysis due to presence of the test compound. To this was then added 0.05 ml of PMN extract and the rate of change of optical density (ΔOD/min) was measured and recorded at 410 mμ using a Beckman Model 35 spectrophotometer. | Novel beta lactam compounds having potent elastrase inhibition activity are disclosed. These compounds are characterized by the general structural formulae I, II, and III: ##STR1## These compounds are further characterized such that X and Y are each --S-- or --CH 2 --, with at least one of X and Y being --S--, or alternatively, X is --SO-- or --SO 2 -- and Y is --CH 2 --; R 1 is hydrogen, tri(lower alkyl)silyl, --COOR" or --CONHR"', wherein R" and R"' are each lower alkyl or phenyl(lower alkyl), and may be the same or different; R 3 is hydrogen, lower alkyl or (lower alkyl)oxy; one of B and D is (lower alkyl)oxycarbonyl, (lower alkenyl)oxycarbonyl, allyloxycarbonyl or phenyl(lower alkyl)oxycarbonyl; and the other of B and D is hydrogen or lower alkyl.
The compounds are useful as anti-inflammatory agents, particularly in the treatment of adult respiratory distress syndrome and rheumatoid arthritis. | 2 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a guidance method of flood water for protecting, from flood water, specific zone where general residence and public facility such as school are built, as safety zone. The invention also relates to a guidance system of flood water used for carrying out the guidance method.
[0003] 2. Description of the Prior Art
[0004] One of the basic plans of Japanese river improvement administration is to flow rain water or flood to the sea swiftly since Meiji. Another basic plan is not to collect the rain water and not to flow the water at once. In accordance with these basic plans, many rivers were repaired in the shape of straight line, and the bank has been hardened with a stone wall and concrete. Moreover, many dams have been built at the upstream of a big river.
[0005] It is granted that drainage of the river which was modified into a straight shape and hardened by means of concrete has been enhanced. Further, it is also granted that a dam is built at upstream and flood of river has been prevented in tome degree. However, natural environment of mountain where the dam was built is destroyed, and the river where the bank was hardened by means of concrete, stone wall and the like is turned into the artificial waterway. And the fishes living in river decrease in number, and the animals living around the bank of river are extinct or seriously endangered. Even if river improvement which destroys environment is carried out, damage by a flood is caused like Tokai heavy rain on September, 1999. It must be granted that there is a limit in the river improvement method for collecting flood water or rain water into a dam, and in the river improvement method for pushing rain water into river. The above fact is recognized in the U.S. and Europe, and it is granted that there is a possibility that river overflows, and the river improvement method has been changed into a direction that does not oppose the nature. In reply to this change, Japanese River Council of the Ministry of Construction submitted a response at the end of 1999 to the effect that the river improvement should be proceeded en the entire drainage area on the assumption that a river floods.
SUMMARY OF THE INVENTION
[0006] The present invention has been accomplished in view of the above facts of flood and the reply, and it is an object of the present invention to provided a guidance method of flood water for protecting and a guidance system of flood water used for carrying out the guidance method which protects, from flood water, specific zone where general residence and public facility such as school are built, as safety zone even if river or sea water overflows. More specifically, it is an object of the invention to provided a guidance method of flood water for protecting and a guidance system of flood water used for carrying out the guidance method in which specific zone is protected as safety zone from the flood water without deteriorating landscapes of the specific zone. In addition to the above object, it is another object of the invention to provided an inexpensive guidance method of flood water for protecting and an inexpensive guidance system of flood water used for carrying out the guidance method in which specific zone is protected as safety zone from the flood water even at the time of power failure.
[0007] The above objects are achieved by a structure in which a guidance plate is buried in underground where it is expected to be upstream of water flow when a bank of river, reservoir or port is destroyed, and the guidance plate is raised to a surface of earth when the flood water flows, or flowed or is expected to flow, thereby guiding the flood water into a predetermined direction by means of the guidance plate. Further, relatively high-rise buildings such as school and building are equipped with water tanks such as water tank and tank for disaster prevention. Therefore, the water in such a water tank may be used. If the water in the water tank is used, the guidance plate can be driven upwards also in case of emergency when tap water can not be obtained. To achieve the above objects, according to a first aspect of the present invention, there is provided a guidance method of flood water wherein a guidance plate is laid under underground in the vicinity of upstream side of a specific zone where a general residence, a school, a public facility like a hospital or the like is built and where it is anticipated that the flood water flows, and when flood water is generated, or when there is a possibility that flood water may be generated, the guidance plate is raised to a predetermined height of surface of the earth, a specific zone is secured as a safety zone by diverting the flood water from the specific zone by means of the raised guidance plate, and by guiding the flood water to a retarding basin, a drainage canal, and the like. According to a second aspect of the invention, the guidance plate is raised by water pressure, such as tap water and impounded water. According to a third aspect of the invention, there is provided a guidance system of flood water comprising a guidance plate provided under underground in the vicinity of upstream side of a specific zone where a general residence, a school, a public facility like a hospital or the like is built and where it is anticipated that the flood water flows, the guidance plate diverting the flood water from the specific zone and guiding the flood water to a retarding basin, a drainage canal, and the like, and the guidance system further comprising a drive system for driving the guidance plate to a predetermined height position of surface of the earth, wherein the drive system comprises a piston cylinder unit which is operated by water pressure such as tap water and impounded water.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] [0008]FIG. 1 is a schematic perspective view of burying position of a guidance system of flood water according to an embodiment of the present invention and an operation state of the guidance system;
[0009] [0009]FIG. 2 show a first embodiment of the invention, wherein FIG. 2(A) is a schematic perspective view showing the entire guidance system, and FIG. 2(B) is a schematic sectional view showing a hydraulic piston cylinder unit; and
[0010] [0010]FIG. 3 is a partially sectional schematic front view of a second embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0011] Embodiments of the present invention will be explained with reference to the accompanying drawings below. FIG. 1 is a perspective view showing places where guidance systems 1 for flood water of the invention are disposed. In FIG. 1, a reference symbol Ri represents river, reference symbols S 1 and S 2 represent first and second safety zones or specific zones where public facilities such as general residence, school and library. Since the river Ri is bent at a point D, if a bank Ba is to be broken, it is expected that the bank Ba is broken at this point D. It is expected that a portion of the flowing water flows as flood water toward the first and second specific zones S 1 and S 2 located lower than the bank Ba. Thereupon, the guidance systems 1 according to the present embodiment are buried underground in the vicinity of upstream ends S′ 1 and S′ 2 of the first and second specific zones S 1 and S 2 , and in the vicinity of a portion S″ 1 where it is expected that the wafer bypasses and flows toward a side of the first specific zone S 1 . When the bank Ba is actually broken and flood water flows, or when there is an adverse possibility that the river overflows, guidance plates 5 , 5 are driven to a predetermined height position the road surface from an underground room, and the flood water is guided to a retarding basin, a tailrace or the like. With this, the first and second specific zone S 1 , S 2 are protected against the flood water as safety zones. The flood water which is guided by the guidance plates 5 , 5 and allowed to flow in this manner is shown with a large number of arrows in FIG. 1.
[0012] The guidance system 1 of flood water according to a first embodiment includes a guidance plate 5 . The guidance plate 5 has an upper end edge 2 , a lower end edge 3 and opposite side edges 4 , 4 , and is bent substantially at right angles. The upper end edge 2 of the guidance plate 5 is a portion of the road surface in a state where the upper end edge 2 is stored an underground room UR which will be described later. Therefore, the upper end edge 2 has the same color as that of the road surface therearound or is covered with lawn. First and second hydraulic piston cylinder units 20 , 20 are mounted to the lower end edge 3 as will be described later, and the opposite side edges 4 , 4 are guide portions. The guidance plate 5 having the above structure is stored or buried in the underground room UR located at a predetermined upstream position where it is expected that the flood water flows, and in case of an emergency, the guidance plate 5 is driven to the predetermined height position from the road surface. A pair of guidance columns 7 , 7 which guide the guidance plate 5 and receives water pressure of the flood water extend to a predetermined height of the road surface from a floor surface F of the underground room UR at a predetermined distance from each other. The guidance columns 7 , 7 are formed with recess grooves 8 , 8 which guide the opposite side edges 4 , 4 of the guidance plate 5 in the longitudinal direction. The guidance columns 7 , 7 stand on the floor surface F such that the recess grooves 8 , 8 are opposed to each other.
[0013] A driving apparatus which drives the guidance system 1 toward the road surface comprises first and second hydraulic piston cylinder units 20 , 20 in this embodiment and thus, only one of them, i.e., the first hydraulic piston cylinder unit 20 will be explained, and for the other piston cylinder unit 20 , only reference symbols are designated and explanation thereof will be omitted. The first hydraulic piston cylinder unit 20 is formed into a telescopic structure. That is, in accordance with the embodiment shown in FIG. 2(B), the driving apparatus comprises first and second hydraulic cylinders 21 , 22 . More specifically, the driving apparatus comprises, the first hydraulic cylinder 21 which is fixed to the underground room UR and which has relatively large diameter, the second hydraulic cylinder 22 which is provided in the first hydraulic cylinder 21 such that the second hydraulic cylinder 22 can reciprocate therein, a piston 25 provided in the second hydraulic cylinder 22 such that the piston 25 can reciprocate therein, and a piston rod 26 which is integrally formed on the piston 25 . A bottom of the second hydraulic cylinder 22 is formed with a through hole 24 , the bottom functions as a piston portion 23 , and this piston portion 23 comes into close contact with an inner peripheral surface of the first hydraulic cylinder 21 and reciprocates. An upper end of the piston rod 26 having the above structure is fixed to a lower edge 3 of the guidance plate 5 . Therefore, if tap water is supplied from a water feed pipe 35 , the tap water supplied to a piston head chamber of the first hydraulic cylinder 21 passes through the through hole 24 and is also supplied to a piston head chamber of the second hydraulic cylinder 22 . With this feature, although rising speed or lifting power and the like of the second water pressure cylinders 23 and the pistons 25 differ because of a difference in pressure-receiving surfaces of the piston 25 and the piston portion 23 of the second water pressure cylinder 22 , and because of a difference in volume of the piston head chambers of the piston 25 and the piston portion 23 , the piston rod 26 finally rises, and the guidance plate 5 is driven to the predetermined position.
[0014] As shown in FIG. 2(B), the feed water supply system 30 includes a feed pipe 31 . One end of the feed pipe 31 is connected to a water supply pipe through an open/close valve 32 . A cross valve 34 , a check valve and the like (not shown) are provided on the other end of the feed pipe 31 . The feed pipe 31 is branched into two branch pipes 35 and 35 . Orifices 36 and 36 are provided on the branch pipes 35 and 35 , and the branch pipes 35 and 35 are respectively connected to the piston head chambers of the first water pressure cylinders 21 and 21 of the first and second water pressure type piston cylinder units 20 and 20 . Since the orifices 36 and 36 are provided on the branch pipes 35 and 35 in this manner, if a difference in the rising position of the first and second water pressure type piston cylinder units 20 and 20 is generated, a difference in pressure of the piston head chambers of the first and second water pressure type piston cylinder units 20 and 20 is also generated due to a difference in driving force. If the difference is caused, a pressure difference between inlet side and outlet side of the orifices 36 and 36 is also changed. As a result, water amount flowing through the orifices 36 and 36 is changed. With this, the first and second water pressure type piston cylinder units 20 and 20 are driven with the same water amount and in the same manner.
[0015] According to this embodiment, an on/off valve 32 is disposed in the safety zone. Thus, it is possible to open the on/off valve 32 to supply the tap water to the first and second hydraulic piston cylinder units 20 , 20 , and to drive the guidance plate 5 to the upper predetermined position, from a safety place without being exposed to danger such at the time of overflowing of river. The cross valve 34 can be disposed in the safety zone. Further, since the check valve is provided, even if the supply of tap water is stopped by any reason, the guidance plate 5 is not lowered unintentionally. One pipe of the cross valve 34 is opened at a drain groove.
[0016] Next, operation will be explained. The guidance plates 5 , 5 are buried in the predetermined positions as described above. In a normal state, a function of the check valve is canceled, and a state of the cross valve 34 shown in FIG. 2(B) is switched to a state in which water can be discharged. With this operation, water in the first and second water pressure type piston cylinder units 20 and 20 is discharged into the ditch D through the check valve and the cross valve 34 . The guidance plate 5 is lowered until it abuts against the support member or the stopper by its own weight (this state is not shown in FIG. 2), and the upper end edges 2 of the guidance plates 5 , 5 come to substantially the same height as that of the road surface. With this, the upper end edges 2 of the guidance plates 5 , 5 become a portion of the road surface, and it is unnecessary to be aware that the guidance plates 5 , 5 are buried in the underground room UR. Landscapes therearound are not deteriorated. The guidance columns 7 , 7 are indexes of the guidance plates 5 , 5 .
[0017] When the bank Ba of the river Ri was broken and water overflowed, or when there is an adverse possibility of overflowing from judgement of an amount of rain water or the like, the cross valve 34 is switched to a position shown in FIG. 2(B), and the on/off valve 32 is opened. With this, tap water is equally supplied to the first and second hydraulic piston cylinder units 20 , 20 by the above-described reason. The second hydraulic cylinders 22 , 22 and the pistons 25 , 25 are driven to predetermined height positions of the road surface. With this, the flow of the flood water is forcibly changed by the guidance plates 5 , 5 , and the flood water is guided toward the retarding basin, tailrace or the like. The flood water which is guided by the guidance plates 5 , 5 and allowed to flow in this manner is shown with a large number of arrows in FIG. 1.
[0018] Stoppers (not shown in FIG. 2) are mounted to the first and second hydraulic piston cylinder units 20 , 20 or the guidance columns 7 , 7 for limiting the upward driving amount of the guidance plates 5 , 5 . Therefore, even if the supply of tap water is continued, the guidance plates 5 , 5 stop at the predetermined positions. At that time, since the pressure of the tap water is relatively low, the first and second hydraulic piston cylinder units 20 , 20 and the like are not broken. The water feed pipe may be provided with a relief valve for safety if necessary.
[0019] Next, a second embodiment of the present invention will be explained with reference to FIG. 3. The same constituent elements as those in the first embodiment are designated with the same reference numbers or characters, or dash “′” is added to the reference numbers or characters, and the same explanation is omitted. According to the second embodiment, a pair of guidance columns 40 , 40 are usually accommodated in the underground room UNDERGROUND ROOM. When a guidance plate 5 ′ is driven toward the road surface, the guidance columns 40 , 40 are also driven toward the road surface in a telescopic manner. That is, each of the guidance columns 40 , 40 comprises a cylindrical guide member 41 of predetermined length fixed to the floor surface F of the underground room UR, and a support column 42 which is telescopically inserted into the guide member 41 . A pair of guide rollers 43 , 44 are mounted to an inner side portion of an upper portion of the guide member 41 at a predetermined distance from each other in the vertical direction such that the support column 42 is guided by the guide rollers 43 , 44 . Side edges 4 ′, 4 ′ of the guidance plates 5 , 5 are fixed to upper portions of the support columns 42 , 42 which are guided in the vertical direction. According to this embodiment, the guidance plate 5 ′ is of flat plate shape.
[0020] It is obvious that the second embodiment also exhibits the same effect. That is, if tap water is supplied to the first and second hydraulic piston cylinder units 20 , 20 , it is obvious that the guidance plate 5 ′ is driven upward and the support columns 42 , 42 extend in association with this movement. At that time, since the support columns 42 , 42 are supported by the pair of guide rollers 43 , 44 disposed at a distance from each other in the vertical direction, it is obvious that the water pressure of the flood water can be received. When there is an adverse possibility that great water pressure of the flood water is received, a plurality of guidance columns may be provided on a back surface of the guidance plate. According to this embodiment, since the guidance columns 40 , 40 are also buried in the underground room UR, landscapes are not deteriorated by the guidance system of flood water. In order to maintain the landscapes more excellently, soil 2 ″ may be placed on the upper end edge 2 ′ of the guidance plate 5 ′, and lawn or the like may be planted to cover the guidance plate 5 ′.
[0021] The present invention can be variously carried out without being limited to the first and second embodiments. For example, when the water supply tank is disposed at a high position, if the water feed pipe is connected to the water supply tank, it is possible to drive the guidance plate even if the tap water is stopped. When a rain water tank, a disaster prevention tank or the like is provided, the water feed pipe may be connected to such a tank. Further, if a water pipe connected to the water supply tank, the rain water tank or the like is connected to a tap water pipe in parallel, there is a merit that the guidance plate can be driven by any of the tanks. The guidance plate can also be driven by an electric motor, an internal combustion engine or the like depending upon the burying position.
[0022] A pressure compensation type flow rate adjusting valve may be provided instead of the orifices so that equal amount of water can be supplied to the first and second water pressure type piston cylinder units. It is apparent that the number of water pressure type piston cylinder units is not limited to that shown in the embodiments. According to the embodiment, although the running water is supplied to the water pressure type piston cylinder units, water pressure of the running water is not high. Therefore, the water pressure type piston cylinder units can be made of reinforced plastic which is not subject to corrosion. In that case, maintenance of the unit is easy. The water feed pipe of the hydraulic piston cylinder unit may be provided with an automatic control valve which is operated by remote control, and a safety valve may be provided so that the guidance plate is not operated unintentionally. Although constituent material of the guidance plate is not especially mentioned in the above embodiments, the guidance plate may be made of stainless steel or synthetic resin which is not subject to corrosion. It is obvious that the shape of the guidance plate is not limited to that described in the embodiments.
[0023] As described above, according to the present invention, a guidance plate is buried in underground where it is expected to be upstream of water flow when a bank of river, reservoir or port is destroyed, and the guidance plate is raised to a surface of earth when the flood water flows, or flowed or is expected to flow, thereby guiding the flood water into a predetermined direction by means of the guidance plate. Further, relatively high-rise buildings such as school and building are equipped with water tanks such as water tank and tank for disaster prevention. Therefore, even if the flood water overflows, the specific zone can be secured as the safety zone which is the specific effect of the present invention. Thus, according to the present invention, the specific zone can be protected against flood water without destroying the natural environment by building many dams around the upstream of river, or solidifying the bank of the river with concrete. According to another invention, since the guidance plate is driven by water pressure of tap water or reserved water, the guidance system of floodwater is inexpensive, and the specific zone is protected as safety zone against flood water in case of emergency like a power failure. Further, since the guidance system of flood water is buried underground, landscapes near the specific zone is not deteriorated. | It is an object of the present invention to provide a guidance method for protecting a specific zone as a safety zone against flood water also in case of emergency like a power failure without deteriorating landscapes near the specific zone. In the guidance method of flood water, a guidance plate ( 5, 5, . . . ) is laid under underground in the vicinity (S′ 1 , S′ 2 , S″ 1 ) of upstream side of a specific zone (S 1 , S 2 ) where a general residence, a school, a public facility like a hospital or the like is built and where it is anticipated that the flood water flows, and when flood water is generated, or when there is a possibility that flood water may be generated, the guidance plate ( 5, 5, . . . ) is raised to a predetermined height of surface of the earth, a specific zone (S 1 , S 2 ) is secured as a safety zone by diverting the flood water from the specific zone (S 1 , S 2 ) by means of the raised guidance plate ( 5, 5, . . . ), and by guiding the flood water to a retarding basin, a drainage canal, and the like. | 4 |
BACKGROUND OF THE INVENTION
The present invention is based on a fuel metering device and method for an internal combustion engine with a lambda regulator and a warm-up enrichment, in which at the onset of regulation the warm-up enrichment is reduced or turned off. Such a fuel metering system is already known under the trademark "L-Jetronic". In this system the metering device changes from regulating mode to lambda regulating mode at a time when at least the exhaust sensor has reached its working temperature and therefore is ready. As a rule, warm-up enrichment processes are temperature-dependent in their starting values and are regulated as a function of time.
It has been shown that this known system is not always able to provide a clean exhaust gas under certain operational circumstances because of mixture compositions which are not ideal in these special operational circumstances. This is based on the following physical factors. If the lambda sensor has not been sufficiently heated, it cannot work correctly, except with long idle times. For this reason the result is a mixture not equal to lambda=1 (rich or lean) for relatively long periods of time, which deficiency leads to strong exhaust emissions. This problem becomes especially noticeable during the change from overrun to normal driving conditions.
During overrun the lambda regulator aims for a median lambda value onto which is superimposed the normally multiplicatively-acting warm-up enrichment during the warm-up phase. The lambda regulator goes again into action at the end of the overrun and, because of the relatively slow lambda sensor, it takes a comparatively long time until the lambda regulator with its several switching points goes into action.
OBJECT AND SUMMARY OF THE INVENTION
The fuel metering device and method in accordance with the present invention wherein a warm-up enrichment is reduced when lambda regulation begins assures that, at the beginning of a lambda regulating phase, the range to be regulated does not require too large differences and, therefore, unfavorable exhaust gas values occur only for short periods of time.
The switching off of the warm-up phase is important, for instance when using so-called warm-up performance graphs or additive enrichment in which several warm-up factors are used, depending on load or rpm conditions. This switching-off operation also avoids large incorrect adaptations in the dynamic operation during the idle time of the regulating system.
The invention will be better understood and further objects and advantages thereof will become more apparent from the ensuing detailed description of a preferred embodiment taken in conjunction with the drawing.
BRIEF DESCRIPTION OF THE DRAWING
The only FIGURE in the drawings shows in rough diagram form the electrical part of a fuel metering device.
DESCRIPTION OF THE PREFERRED EMBODIMENT
An injection system is used as the basis of the preferred embodiment. It should be noted that the present invention is not dependent on the type of fuel metering system and therefore can also be used with regulated carburetor devices.
Sensors for the rpm and the weight rate of the air flow are designated by 10 and 11. They pass on their output signal to the timing element 12 in which impulses of the duration tp are formed as base injection impulses. A correction stage 13 then follows which leads to at least one electromagnetic injection valve 14.
A lambda sensor is designated by 15. Assigned to it is a sensor-temperature probe 16 to the outlet side of which a threshold value stage 17 is coupled. Dependent on the output signal of the threshold value stage 17, the signal of the lambda sensor 15 is passed on by way of a switch 18 to the correction input 19 of the correction stage 13. In practice it is not really necessary, however, to assign a separate temperature probe 16 to the lambda sensor 15, because in many instances the readiness of the sensor is determined from the signal emitted by it; however, this split-up best shows the nature of the present invention. A sensor 20 for the engine temperature influences, also by way of the input 21, the processing of the signal in the correction stage 13. It is important to dispose between the temperature sensor 20 and the correction input 21 a switch 22 switchably dependent on the readiness of the sensor or the start of the lambda regulation.
The switching arrangement shown in the FIGURE is already known, with the exception of the switch 22. Once the lambda sensor 15 has reached its operating temperature, and with it its readiness, the lambda regulator switches on and the fuel metering system changes over from open-loop control operation to closed-loop control operation. This change-over is accomplished by means of the switched-on contact of the lambda-sensor output signal at the input 19 of the correction stage 13.
The position of the switches 18 and 22 is in relationship to the not-ready-for operation sensor, i.e. when the lambda regulation is switched off and the warm-up enrichment is operating. When changing to lambda regulation, however, the switch 22 is opened and turns off the warm-up enrichment with the consequence that the regulator needs to control a considerably smaller lambda value since the mixture previously prepared was too rich, as a rule, because of the warm-up enrichment.
The same holds true during a transition from the overrun operation with a cut-off of the fuel supply to normal operational mode. During the cut-off phase the integrator normally contained in the lambda regulator is set for a median value (switch 18 is turned off through the control input 23), so that during the transition to normal operation the control stroke does not take on too large values, because the warm-up enrichment does not take place.
Besides turning off the warm-up influence in accordance with the above examples, the warm-up enrichment can simply be reduced to a lower value and/or a normally time-dependent post-start boost 25 can be reduced. As a rule, however, the post-start boost would already be turned off at the time the lambda sensor is operational.
It is furthermore possible to reduce the warm-up enrichment post start boost 25 in accordance with a special time function following the operational readiness of the sensor, instead of turning it completely off. This is symbolically shown by a broken line and a separate box 24.
Which one of the possibilities shown above is used with a specific fuel metering system for an internal combustion engine is dependent on the circumstances and cannot be determined in general. It will be a compromise between sufficient driving comfort and exhaust gas of the greatest possible cleanliness, especially in the transition areas.
Depending on the use it is important that a renewed warm-up enrichment does not take place during the cooling off period of the lambda sensor, e.g. during the low-rpm idling operation and the transition into open-loop control operation caused by it and based on the non-operational status of the sensor. This delay could be realized by means of a simple holding circuit, for instance, for the switch 22.
The foregoing relates to a preferred exemplary embodiment of the invention, it being understood that other embodiments and variants thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims. | A fuel metering system and method for an internal combustion engine is proposed, having a lambda regulation device and a warm-up enrichment, in which at the onset of regulation the warm-up enrichment is reduced or turned off for the purpose of not having an abnormally high control stroke when transferring to a closed-loop operation and thereby rapidly attaining a stable lambda value. | 5 |
CLAIM OF PRIORITY
This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 from my application entitled AIR CONDITIONER HAVING PRESSURE CONTROLLING UNIT AND ITS CONTROL METHOD filed with the Korean Industrial Property Office on Dec. 18, 2000 and there duly assigned Ser. No. 2000-77926.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to air conditioner, and more particularly to an air conditioner with a pressure regulation device and method for controlling the same.
2. Description of the Prior Art
An air conditioner generates cool air using a refrigeration cycle, and supplies it into a room.
The refrigeration cycle employed in the air conditioner is comprised of a compressor, a condenser, a capillary tube and an evaporator. Gaseous refrigerant sucked into the compressor is compressed into high-temperature, high-pressure gaseous refrigerant by the operation of a motor within the compressor. The compressed gaseous refrigerant discharged from the compressor is condensed (liquefied) to high-pressure liquid refrigerant by heat exchange with outdoor air supplied by a condenser fan. The condensed refrigerant in the condenser is expanded while passing through the capillary tube. The expended refrigerant is evaporated by heat exchange with indoor air, by which process the refrigerant absorbs heat from the surroundings.
FIG. 1 is a schematic diagram showing the construction of the outdoor unit of a conventional air conditioner.
Referring to drawing, the conventional outdoor unit includes a first compressor 1 a and a second compressor 1 b that are operated at constant-speeds and connected in parallel. In order to separate oil from refrigerant discharged from the compressors 1 a and 1 b, a first oil separator 2 a is connected to the outlet side of the first compressor 1 a and a second oil separator 2 b is connected to the outlet side of the second compressor 1 b. The outlet sides of the first and second oil separators 2 a and 2 b are merged together and then connected to first and second condensers 6 a and 6 b through a four-way valve 5 . The first and second condensers 6 a and 6 b are connected to an indoor unit (not shown) through a liquid receiver 8 . A first condenser fan 7 a is situated in the vicinity of the first condenser 6 a and a second condenser fan 7 b is situated in the vicinity of the second condenser 6 b. The refrigerant-return side of the indoor unit is connected to the inlet sides of the first and second compressors 1 a and 1 b through an accumulator 9 .
A pressure-equalizing pipe 3 for equalizing the pressures of the refrigerant of the first and second compressors 1 a and 1 b and an oil-equalizing pipe 4 for equalizing the quantities of the oil of the first and second compressors 1 a and 1 b are each provided to connect the first and second compressors 1 a and 1 b.
A conventional method for controlling the conventional outdoor unit of the conventional air conditioner is described hereunder.
FIG. 2 is a flow chart showing the operation of the conventional outdoor unit of the conventional air conditioner.
In the operation of the conventional outdoor unit, when an increase of the total capacity of the outdoor unit is required according to a capacity-increase command while one compressor is being operated and the other compressor is being stopped(S 10 ), the compressor being currently operated is stopped and made to wait for a predetermined time period (S 20 ) to reduce a pressure difference between the compressor being operated and the other compressor being stopped. When it is determined that the predetermined time period has elapsed (S 30 ), the two compressors are started at the same time (S 40 ).
In the conventional outdoor unit operated as described above, when one compressor is intended to be started while the other compressor is being operated, there is a great concern that the compressor will not start due to the large pressure difference between its inlet and outlet sides.
Accordingly, in this case, it is necessary to reduce the pressure difference between the inlet and outlet sides of the compressor intended to start.
As described above, when the total capacity of the air conditioner should be increased while one of two compressors is being operated, the compressor being operated should be stopped before the other compressor is operated. Accordingly, the cooling or heating operation of the air conditioner is stopped for the predetermined time period, so that there occurs a problem that the comfort of a user is decreased by the stoppage of air conditioning.
SUMMARY OF THE INVENTION
Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide an air conditioner with a pressure regulation device and method for controlling the same, which is capable of starting one or more additional compressors without hindrance when it is necessary to start the additional compressors according to an increase capacity thereof.
In order to accomplish the above object, the present invention provides an air conditioner with pressure regulation device, the air conditioner controlling the number of operated compressors according to load, comprising: a bypass conduit for guiding gaseous refrigerant from the outlet side of compressor to the inlet side of the compressor; a bypass valve arranged on the bypass conduit for selectively opening and shutting the bypass conduit; and a control unit for controlling the opening and closing of the bypass valve so as to assist of the compressor in stop.
In addition, the present invention provides a method for controlling an air conditioner, the air conditioner being comprised of a bypass conduit for guiding gaseous refrigerant from the outlet side of compressor to the inlet side of the compressor; a bypass valve arranged on the bypass conduit for selectively opening and shutting the bypass conduit; and a control unit for controlling the opening and closing of the bypass valve so as to assist of the compressor in stop, a plurality of compressors operated according to load, a plurality of bypass conduits for guiding gaseous refrigerant from the outlet sides of the compressors to the inlet sides of the compressors, and a pressure regulation unit consisting of a first valve disposed between the inlet side of the compressor and a refrigerant conduit connected to the return side of the indoor unit of the air conditioner, a capillary tube connected in parallel with the first valve and a second valve connected in serial with the capillary tube to be selectively opened and closed, comprising the steps of: opening the bypass valves for one or more compressors to be started, and closing all the valves of the pressure regulation units for one or more compressors to be started; starting the compressors and reducing the pressure difference between the interior and exterior of each of the compressors stage by stage by controlling the opening of the pressure regulation units; and shutting the bypass conduits and normally driving the compressors.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein:
FIG. 1 is a schematic diagram showing the construction of the outdoor unit of a conventional air conditioner;
FIG. 2 is a flow chart showing the operation of the conventional outdoor unit of the conventional air conditioner;
FIG. 3 is a schematic diagram showing the construction of the outdoor unit of an air conditioner with a pressure regulation device in accordance with the present invention;
FIG. 4 is a block diagram showing the control of the air conditioner of the present invention; and
FIG. 5 is a flowchart showing the operation of the air conditioner of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 3 is a schematic diagram showing the construction of the outdoor unit of an air conditioner with a pressure regulation device in accordance with the present invention.
With reference to this drawing, the outdoor unit of the present invention includes a plurality of constant-speed compressors. In this embodiment, the constant-speed compressors are comprised of a first compressor 11 and a second compressor 12 that are connected in parallel. An pressure-equalizing pipe 13 for equalizing the pressures of the refrigerant of the first and second compressors 11 and 12 and an oil-equalizing pipe 14 for equalizing the quantities of the oil of the first and second compressors 11 and 12 are each provided to connect the first and second compressors 11 and 12 to each other.
In order to separate oil from refrigerant discharged from the compressors 11 and 12 , a first oil separator 21 is connected to the outlet side of the first compressor 11 and a second oil separator 22 is connected to the outlet side of the second compressor 12 .
A first bypass conduit 31 is arranged to guide refrigerant from the outlet side of the first oil separator 21 to the inlet side of the first compressor 11 , and a first bypass valve 32 is disposed on the first bypass conduit 31 to selectively open and shut the first bypass conduit 31 . A second bypass conduit 33 is arranged to guide refrigerant from the outlet side of the second oil separator 22 to the inlet side of the second compressor 12 , and a second bypass valve 34 is disposed on the second bypass conduit 33 to selectively open and shut the second bypass conduit 33 .
Meanwhile, the outlet sides of the first and second oil separators 21 and 22 are merged together and then connected to first and second condensers 51 and 61 through a four-way valve 40 . The condensers 51 and 61 are connected to an indoor unit (not shown) through a liquid receiver 70 . A first condenser fan 52 is situated in the vicinity of the first condenser 51 and a second condenser fan 62 is situated in the vicinity of the second condenser 61 . The refrigerant return side of the indoor unit is connected to an accumulator 80 , and the outlet side conduit 81 of the accumulator 80 is branched into a first refrigerant conduit 82 connected to the inlet side of the first compressor 11 and a second refrigerant conduit 83 connected to the inlet side of the second compressor 12 .
A first pressure regulation unit 90 is arranged on the first refrigerant conduit 82 , and a second pressure regulation unit 100 is arranged on the second refrigerant conduit 83 . The first and second pressure regulation units 90 and 100 serve to regulate the suction pressures of started compressors stage by stage, together with the first and second bypass valves 32 and 34 .
Each of the first and second pressure regulation units 90 and 100 includes a first valve 91 or 101 arranged on the first or second refrigerant conduit 82 or 83 connected to the inlet side of the first or second compressor 11 or 12 , a capillary tube 93 or 103 connected in parallel with the first valve 91 or 101 , and a second valve 92 or 102 connected in serial with the capillary tube 93 or 103 for adjusting the opening of the inlet side of the compressor 11 or 12 .
In this case, the capillary tube 93 or 103 and the second valve 92 or 102 directly connected to the capillary tube 93 or 103 can be displaced by a motorized valve the degree of opening of which can be adjusted. The entire pressure regulation unit 90 or 100 can be displaced by a motorized valve, too.
Also, the entire pressure regulation unit 90 or 100 can be displaced by a first valve arranged on the refrigerant conduit connected to the inlet side of the compressor, an additional refrigerant conduit 84 or 85 connected in parallel with the first valve 91 or 101 , the diameter of which is smaller than refrigerant conduit, and a second valve 92 or 102 arranged on the additional refrigerant conduit 84 or 85 .
FIG. 4 is a block diagram showing the control of the air conditioner of the present invention.
With reference to this drawing, the air conditioner of the present invention includes a plurality of indoor units 200 . Each of the indoor units 200 includes input means 210 for receiving commands from users, a temperature sensor 220 for sensing indoor temperatures, and an indoor unit controller 230 for transmitting information input through the input means 210 to an outdoor unit controller (will be described). In this case, the input means 210 may include a remote controller.
The air conditioner of the present invention further includes the outdoor unit controller 310 for determining the amount of load using information transmitted from the indoor units 200 , a valve drive 320 for regulating the opening of the first and second bypass valves 32 and 34 and the first and second pressure regulation units 90 and 100 , a fan drive 330 for driving the first and second condenser fans 52 and 62 , a four-way valve drive 340 for switching the fluid passages of the four-way valve 40 , and first and second compressor drives 350 and 360 for driving the first and second compressors 11 and 12 , respectively.
The air conditioner of the present invention is characterized in that there can be prevented the failure of the start of one or more additional compressors due to the pressure difference between the interior and exterior of the additional compressors while one or more compressors are operated. This will be described in detail with reference to FIG. 5 .
FIG. 5 is a flowchart showing the operation of the air conditioner with a pressure regulation device in accordance with the present invention.
With reference to FIG. 5, when a capacity-increase command is input to drive an additional compressor (S 110 ) so as to increase the capacity of the air conditioner, the outdoor controller 310 opens the second bypass valve 34 for the second compressor 12 being currently stopped, by controlling the valve drive 320 (S 120 ). The outdoor controller 310 shuts all the valves of the second pressure regulation unit 100 (S 130 ). As a result, the outlet and inlet sides of the second compressor 12 being stopped are connected to each other through the second bypass conduit 33 , so that high-pressure gaseous refrigerant flows from the first compressor 11 to the inlet side of the second compressor 12 , thereby first reducing the pressure difference between the interior and exterior of the second compressor 12 .
After the second compressor 12 is started, the outdoor unit controller 310 determines if a predetermined time period has elapsed (S 150 ). The predetermined time period, for example, may be three minutes, and is a time period during which the pressure difference between the interior and exterior of the second compressor 12 is decreased sufficiently in order not to hinder the compressor from starting.
If it is determined that the predetermined time period has elapsed in STEP S 150 , the outdoor unit controller 310 opens the second valve 102 of the second pressure regulation unit 100 (S 160 ). In this case, the pressure in the inlet side of the second compressor 12 is greater than the pressure in the inlet side of the capillary tube 103 , so the pressure in the inlet side of the second compressor 12 is transmitted to the inlet side of the capillary tube 103 through the capillary tube 103 . Accordingly, the pressure in the inlet side of the second compressor 12 is reduced, while the pressure in the inlet side of the capillary tube 103 is increased.
The outdoor unit controller 310 opens the first valve 101 of the second pressure regulation unit 100 (S 170 ), shuts the second valve 102 of the second pressure regulation unit 100 (S 180 ), and shuts the second bypass valve 34 (S 190 ). Accordingly, the pressure in the inlet side of the second compressor 12 is reduced by one stage and the pressure of gaseous refrigerant returned from the indoor unit is increased by one stage, so both pressures are equalized.
The starting of the second compressor 12 is completed by reducing the pressure difference between the inlet side and outlet side of the second compressor 12 stage by stage. When the starting of the second compressor 12 is completed, the outdoor controller 310 normally drives the second compressor 12 by controlling the second compressor drive 360 (S 200 ).
The above-described procedure can be applied to the case, in which the first compressor 11 is started while the second compressor 12 is operated and the first compressor 11 is stopped.
As described above, the air conditioner with a pressure regulation device and method for controlling the same of the present invention is capable of safely starting one or more additional compressors without stopping one or more compressors in operation when the former compressors are started during the operation of the latter compressors, thereby maintaining comfortable air conditioning without stoppage.
Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. | Disclosed herewith is an air conditioner with a pressure regulation device. The air conditioner controls the number of operated compressors according to load. The air conditioner includes a plurality of bypass conduits for guiding gaseous refrigerant from the outlet sides of compressors to the inlet sides of the compressors. A plurality of bypass valves are arranged on the bypass conduits for selectively opening and shutting the bypass conduits. A control unit controls the opening and closing of the bypass valves so as to control pressure in the inlet sides of one or more started compressors during the starting of the compressors. In addition, a method for controlling the air conditioner is disclosed. | 5 |
This is a continuation of Application Ser. No. 024,612, filed Mar. 11, 1987.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The subject invention relates to sports racquets and, more particularly, to a double faced racquet for providing different string tensions.
2. Description of Related Art
In the prior art, it is known that different string tensions and grip "feels" on tennis racquets affect playing performance. Generally speaking, the higher the tension, the greater the control and the lower the tension, the greater the power. Improper string tensioning can result in too much rebound off the center of the racquet, loss of control over off-center hits, excessive vibration or a very harsh or "dead" feel.
It is further possible to alter the pace of the game and prepare for different styles of play be varying the tension on the racquet. It has occurred to the inventors that it would be advantageous to provide a racquet which provides more than one available tension which can be selected during play by slight of hand. It has further occurred to the inventors that a variable pressure racquet grip would permit adaptation of the grip to various situations and styles of play. Provision of such a racquet must overcome several obstacles, including the need to maintain a lightweight design and provide a properly balanced design.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the invention to provide an improved sports racquet.
It is another object of the invention to provide a sports racquet providing different string tensions.
It is yet another object of the invention to provide a sports racquet having two tensions which may be readily selected during play by slight of hand without mechanized adjustments.
It is still another object of the invention to provide a sports racquet with an adjustable grip "feel".
These and other objects and advantages are achieved according to the invention by a racquet having two sets of strings, one on each side of a racquet face, each set being adjusted to provide a different tension. Additional features include a grip which indicates to the player which racquet face he is using by associating a different feel with each side of the racquet. Another novel feature is the provision of an inflatable grip which may be permanently adjusted to vary the feel of the grip. Finally, a cassette loadable feature is disclosed wherein cassettes of various string tensions may be loaded into a racquet receptacle.
BRIEF DESCRIPTION OF THE DRAWINGS
The just summarized invention will now be described in detail in conjunction with the drawings of which:
FIG. 1 is a perspective view of a racquet according to the preferred embodiment;
FIG. 2 is a side view of the racquet of the preferred embodiment;
FIG. 3 is a perspective cut away illustrating an inflatable grip according to the preferred embodiment;
FIG. 4 is a perspective of the opposite end of the inflatable grip of FIG. 3;
FIG. 5 is a perspective of a loadable cassette embodiment; and
FIG. 6 is a sectional perspective of a racquet according to the preferred embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 illustrates a racquet 11 according to the preferred embodiment. While the embodiment will be described with reference to a tennis racquet, it will be understood that the invention is not limited thereto but is applicable to other racquet designs for other racquet sports such as racquetball, squash, etc. The racquet includes a frame 12 of aluminum, graphite, ceramic, fiberglass or other suitable material. The front contour of the frame 12 is like that of a typical tennis racquet. The frame 12 includes a neck 15 and a racquet face 17. The neck 15 is fixed in a handle grip 13.
As shown in FIG. 2, the neck 15 widens at the face 17 to provide a wider side dimension 19. This wider side dimension 19 permits the creation of two recessed channels 33, 35 provided in the frame 12 around the periphery of the racquet face 17. Holes 21, 23 are drilled in each channel 33, 35, forming two lines of string holes about the periphery of the racquet face 17. As best seen in FIG. 6, two sets of strings are strung on the racquet 11, one set in each line of holes 23, 25. Each of the sets of strings 25 is wound at a different tension, as hereafter discussed in more detail.
The channels 33, 35 are lined with respective plastic inserts 37, 39. Each insert 37, 39 provides a plastic grommet 22 (FIG. 6) which protrudes through each string hole 21, 23 and protects the strings 25 from direct contact with the metal holes 21, 23, which might tend to damage the strings 25. The recess provided by the channel 33, 35 further protects the strings 25 from wear or damage.
A relatively hard plastic bridge member 26 is inserted into the gap between the two struts 29, 31 of the neck 15 to close the racquet face 17. The insert 26 also contains holes 21, 23 which receive the strings 25 as part of the two lines of string holes distributed around the periphery of the racquet face 17. Screws 45 are screwed through the plastic inserts 37, 39 and into the bridge member 26 on either side of the racquet face 17 to retain the bridge member 26 and plastic inserts 37, 39.
For a midsize tennis racquet, the preferred embodiment has a head dimension "A" of nine and three quarter inches and "B" of twelve and three quarter inches with a total racquet length of twenty seven inches. The number of horizontally running strings 25 is sixteen and the number of vertically running strings 25 is nineteen to give a total number of seventy strings, considering both sides of the racquet. The same number of strings are used in each set and the strings of each set are preferably uniformly spaced, i.e. respective strings run parallel to one another in both horizontal and vertical directions in order to meet the rules of the United States Tennis Association. The preferred width "C" between the two sets of strings ranges from 1/4 inches to 2 inches. Finally, the preferred tension is 40 lbs. for one racquet face and 60 lbs. for the other, although it will be understood that various other tensions can be provided. Various other dimensions can also be provided as desired to yield an oversized or undersized racquet.
As further shown in FIG. 2, the racquet handle grip 13 includes two different cover materials 13a, 13b. These materials 13a, 13b indicate to a player which side of the racquet he is using. The two cover materials 13a, 13b may comprise, for example, leather and Gamma Grip.
FIGS. 3 and 4 illustrate a still further improved racquet handle 50 for use in the preferred embodiment. This handle 50 includes an inflatable hard rubber inner bladder 51, with an inner opening 53 of generally square or rectangular cross-section. The outer contour of the bladder 51 conforms to the shape of a typical racquet handle, e.g. hexagonal as shown. The bladder 51 is inflatable by insertion of a pump needle into a valve 55. The bladder 51 is further surrounded by an outer grip material 52, which may comprise two grip surfaces, such as 13a, 13b.
In operation, the bladder 51 functions like a football or basketball bladder. Inflation and deflation of the bladder 51 varies the feel of the grip 13.
As further shown in FIG. 3, the struts 29, 31 of the racquet neck 15 are formed into a unitary rod 57 which fits snugly into the opening 53 of the bladder 51 in the deflated state. The rod 57 is shown broken off in FIG. 3. It preferably extends to within about one inch of the end of the handle 50 in which the valve 55 is mounted. Inflation of the bladder 51 then serves to fix the bladder 51 to the rod 57 by press-fit. Variation of the degree of inflation beyond the press-fit pressure then varies the grip "feel". Use of this improved inflatable handle structure allows variation in the degree of the absorption of racquet shock, a major factor in tennis elbow. It also permits switching to different grips, e.g. of different color or feel.
As an additional improvement, a face may be made removable, such that another string face with a different tension may be inserted, thus avoiding the necessity to restring the racquet to vary the tension provided. An embodiment achieving such a feature is illustrated in FIG. 5. According to FIG. 5, a "cassette" racquet face insert 61 is provided with a preset tension. This cassette 61 may be inserted and removed from a cooperating racquet frame 71. A number of cassettes 61 are preferably provided, each with a different tension, yielding selectable string tensions. Preferably, the cassette 61 is snap-loadable as by means of fixed retainer tabs 63, 65 and spring-loaded pins 67, 69, which fit into cooperating holes, e.g. 73, 75, 77 in the racquet frame 71. Alternatively, screws may be provided at, e.g. the tab and pin insertion points of FIG. 5 to facilitate removal and replacement of the cassettes 61.
A variety of snap-insertion techniques will of course be apparent to those skilled in the art. Additionally, one or both of the racquet faces of an embodiment such as that shown in FIG. 1 may be cassette loadable.
The invention provides numerous other advantages. Racquet tension may be easily varied as the player advances from beginner to intermediate to advanced player status. The advanced player can use the double sided feature to achieve tactical advantage by slight of hand. In other words, the racquet may be turned around during play to present the string face most suitable for each hit, a process which is assisted by the provision of two different grip materials such that a tactile indication of racquet position may be maintained. Older players or the physically handicapped can select high or low tension. From a teaching point of view, the racquet tension can be changed to a lower tension for instructional purposes.
From the foregoing, it will be appreciated that numerous modifications can be made in the disclosed preferred embodiment without departing from the scope and spirit of the invention. Therefore, it is to be understood that within the scope of the appended claims, the invention may be practiced other than as specifically disclosed herein. | A sports racquet having two string faces each with a different tension to provide variable playing characteristics. The racquet is further equipped with two different grip surfaces to assist the player in detecting which racquet face is in use and with a grip which is inflatable to vary the grip "feed". A cassette loadable racquet face insert is also provided to enable a player to readily change one of the string faces to any of a number of different tension settings. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Ser. No. 60/180,557 filed Feb. 4, 2000.
BACKGROUND OF THE INVENTION
[0002] A. Field of the Invention
[0003] The invention relates generally to surgical microscopes, and more particularly to an improved configurations for linking a microscope body to an external power supply, control device, and light source.
[0004] B. Description of the Prior Art
[0005] A “surgical microscope” for the purposes of the invention is understood to be a microscope that is movable with respect to an object and thus possesses a certain flexibility in terms of any connections to external devices. Such microscopes are very often used in surgical operations. Such microscopes are often also used for industrial or commercial applications.
[0006] Such microscopes often have an integrated illumination system in which the light source is built into the microscope. Often, however, the light source is remotely located so as to minimize heating, weight, and housing dimensions in the region of the microscope body. With such external accessories, the light is directed through a light guide from the external light source to the microscope body, and through the latter onto the surgical field.
[0007] In addition, such microscopes—and video cameras incorporated into them—are often equipped with control elements, for example remotely controllable displacement mechanisms or actuators which comprise on the one hand electrical drive systems but also, on the other hand, sensors or the like whose signals are analyzed in external control systems or circuits.
[0008] Such microscopes are often located on the extension arms of stands, while the external devices and control systems are housed in the column region of the stand.
[0009] The connection between the external devices and the microscope body or the terminals located thereon is accomplished via flexible lines such as light guides, electrical cables, electronic data lines, etc. As a rule there are numerous such lines, which in many applications are a hindrance. In some cases they interfere with visibility, are heavy, result in jamming and limitations of movement, and moreover look untidy. In addition, they are susceptible to malfunction or can cause failures by being damaged. In the field of surgical microscopy, they result in increased surface areas which thus make the overall structure more susceptible to soiling.
[0010] The assignee of the present application has already taken initial steps intended to remedy this unfavorable situation. Assignee's OH stand had provided, between stand arms, a flexible hose through which all the various cables were pulled. This hose was relatively bulky and inflexible, however, and did not make optimum use of space since it had to be made sufficiently large for subsequent installation of an undetermined number of cables, even if not all the cables were pulled through. The dead weight of the hose moreover increased the weight of the stand arms in question.
SUMMARY OF THE INVENTION
[0011] It is thus the object of the invention to implement the connection between the external devices and the microscope body in as lightweight, easily movable, and retrofittable a fashion as possible, and with as few cables as possible.
[0012] The present invention, as broadly defined, achieves this principal object on the basis of a physical size reduction and simultaneous weight reduction. Further improved or developed ways of achieving the object, with greater integration and greater advantages over the existing art, are evident from the various embodiments described herein.
[0013] A preferred configuration of a cable according to the present invention, which optionally can also be used independently of the invention, is coaxially multi-layered, one of the layers, but preferably the core of the cable, being configured as a mirror optical system or fiber optical system or as a liquid light guide, while at least two layers are configured as an at least two-pole power cable. Preferably connected to the light-guide portion of such a cable are electro-optical converters for the transfer of control, sensor, and video signals, while the power supply is connected to the power portion.
[0014] Further improvements and details of the invention are evident from the drawings, which depict exemplary embodiments according to the present invention.
BRIEF DESCRIPTION OF THE DRAWING
[0015] The nature and mode of operation of the present invention will now be more fully described in the following detailed description of the preferred embodiment taken with the accompanying drawing figure, in which:
[0016] [0016]FIG. 1 shows a schematic complete surgical microscope according to the present invention, on a stand, with corresponding external devices;
[0017] [0017]FIG. 2 shows a detail of a light guide modified in accordance with the invention, having electro-optical data converters and apparatuses for reflecting light in and out;
[0018] [0018]FIG. 3 shows another light guide with special armoring;
[0019] [0019]FIG. 4 shows a detail of the armoring as shown in FIG. 3;
[0020] [0020]FIG. 5 shows a variant of the light guide as shown in FIG. 3;
[0021] [0021]FIG. 6 shows a further variant of the light guide as shown in FIG. 3;
[0022] [0022]FIG. 7 shows a multi-strand cable as power and data carrier; and
[0023] [0023]FIG. 8 shows a two-pole cable that serves as both a power line and a data line.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] The figures will be described in overlapping fashion. Identical parts bear identical reference characters; different parts having functions that are identical in principle bear identical reference characters with differing indices. The figures do not limit the invention, but rather are intended as possible exemplary embodiments.
[0025] [0025]FIG. 1 shows a schematic configuration with a stand 11 that bears a microscope body 1 and various external devices 12 . These comprise, for example, a computer 13 for control and measurement tasks, a light source 10 for providing light flux that can be used as a power supply 5 and/or directed to microscope body 1 and onto a surgical field. A power connection 4 c in the form of a light guide transmits power in the form of light flux. A control device is connected to remotely controlled drive systems in the microscope, for example via a data connection 7 c integrated, in accordance with the invention, into power connection light guide 4 c . The microscope thus comprises a terminal 3 for power connection 4 c and a terminal 6 for the data connection.
[0026] In this example, the data connection is implemented via electro-optical converters 9 a and 9 b that convert electrical signals into optical signals and vice versa. These signals are reflected into and out of light guide 4 c via beam splitters or mirrors 14 a and 14 b , so that by way of these, both the light flux from the light source and the optical signals from converter 9 a are sent to the microscope, and optical signals from converter 9 b are sent in the other direction to computer 13 and to control device 2 .
[0027] An extremely wide variety of combinations lies within the context of the invention. For example, the power that is to be transferred can be optical and/or electrical power, while the data can be electrical and/or optical signals. This includes the case in which electrical signals are transferred over the light guide by light modulation.
[0028] Some of the possibilities are explained with references to the examples shown in FIGS. 3 through 8:
[0029] [0029]FIG. 7 shows a relatively simple configuration which does not provide any integrated light flux transfer, but does provide an electrical power transfer in power wires 4 a of a multi-strand cable 8 a , while data transfer occurs in data lines 7 a of the same cable 8 a.
[0030] [0030]FIG. 8 uses only a two-pole power cable 4 b that is of twisted configuration for better shielding effect. By way of this power cable, a high-frequency (relative to the power flow) data transfer is performed simultaneously; for this purpose, corresponding signal couplers 15 a and 15 b are provided, which are connected at the other end to terminal 6 and to computer 13 or control device 2 .
[0031] Signal couplers of this kind are optionally also provided in configurations according to FIGS. 3 through 5, if the electrical lines are also intended to be used for data purposes in the case of these configurations.
[0032] [0032]FIG. 6 shows a light guide 4 e that has as its core a two-pole electrical cable 4 g.
[0033] [0033]FIG. 3 shows another light guide in which a two-pole cable (in this example, a coaxial cable) 4 h is wound as armoring around light guide 4 d . For strengthening purposes, a tubular sheath 16 is also pulled on as an outer layer.
[0034] [0034]FIG. 4 shows a detailed depiction of the coaxial cable according to FIG. 3, which of course in addition to power transfer could also be used for data transfer (although with less bandwidth than in the case of light). In this example, what is intended is a data transfer via light guide 4 d.
[0035] [0035]FIG. 5 shows a combination of the examples shown in FIG. 3 and in FIG. 6, with a single-pole armoring 4 f 2 that, for example, can also be constituted from a conventional corrugated metal tube, and with a single-pole core 4 f 1 inside light guide 4 e. This configuration also results in a favorable shielding effect due to the coaxial configuration of electrical conductors 4 f 1 and 4 f 2 . Data can thus be transmitted through these easily and without interference, so that data transfer via light guide 4 e can optionally be dispensed with.
[0036] The signals mentioned above preferably comprise amplitude-modulated or frequency-modulated current, or light including nonvisible light wavelength regions, for example infrared.
[0037] The invention encompasses, on the one hand, corresponding modulation of the electrical or light fluxes that are flowing in the manner of power, and/or the fact that electrical or optical signals are sent, parallel to these flow power fluxes, over the same line in each case.
List of Reference Characters: 1 Microscope body 2 Control device 3 Power terminal 4 Power connection 5 Power supply unit 6 Data terminal 7 Data connection 8 Cable 9 Conversion device; electro-optical converter 10 Light source 11 Stand 12 External devices 13 Computer 14 Beam splitter 15 Signal coupler 16 Tubular sheath | The invention concerns a microscope having a power and data transfer system between a microscope body ( 1 ) and an external control device or peripheral device ( 2, 13 ). According to the present invention, the power line ( 4 ) and data line ( 7 ) are laid physically together and are of integrated configuration, thus implementing a lightweight connection comprising few individual cables. | 6 |
FIELD OF THE INVENTION
This invention relates to a pressure swing adsorption (PSA) system for purifying an impure supply gas stream containing a desirable pure gas, such as hydrogen, using a continuous feed of the supply gas stream.
BACKGROUND OF THE INVENTION
The need for high purity gases, such as hydrogen, is growing in the chemical process industries, e.g., in steel annealing, silicon manufacturing, hydrogenation of fats and oils, glass making, hydrocracking, methanol production, the production of oxo alcohols, and isomerization processes. This growing demand requires the development of highly efficient separation processes for H 2 production from various feed mixtures. In order to obtain highly efficient PSA separation processes, both the capital and operating costs of the PSA system must be reduced.
One way of reducing PSA system cost is to decrease the adsorbent inventory and number of beds in the PSA process. In addition, further improvements may be possible using advanced cycles and adsorbents in the PSA process. However, H 2 feed gas contains several contaminants, e.g. a feed stream may contain CO 2 (20% to 25%) and minor amounts of H 20 (<0.5%), CH 4 (<3%), CO (<1%) and N 2 (<1%). Such a combination of adsorbates at such widely varying compositions presents a significant challenge to efficient adsorbent selection, adsorbent configuration in the adsorber, and the choices of individual adsorbent layers and multiple adsorbent bed systems to obtain an efficient H 2 -PSA process.
U.S. Pat. No. 6,551,380 B1 relates to a gas separation apparatus and process that has a first PSA unit for receiving feed gas which comprises a first and a second component. First PSA unit produces first product gas predominantly containing the first component, and the first off gas containing at least some of the first component and second component. A compressor is coupled to a first PSA unit to compress first off gas to form compressed off gas, which is passed downstream to an absorber unit, which employs a solvent to remove at least part of the second component from compressed off gas, forming an enriched compressed off gas. Second PSA unit receives enriched compressed off gas and produces second product gas which predominantly contains the first component and a second off gas that is sent to waste or reformer burner.
U.S. Pat. No. 6,521,143 B1 relates to a process that provides for simultaneously producing a syngas product having a H 2 /CO ratio of less than 2.5 and a hydrogen gas product. The process includes increasing an amount of carbon dioxide being fed to a secondary reformer with carbon dioxide extracted from: (a) an effluent from a primary reformer and (b) an effluent from the secondary reformer. An apparatus for performing the process is also provided.
U.S. Pat. No. 6,503,299 B2 relates to a two bed PSA process for recovering a primary gaseous component at a purity of over 99% from a feed gas comprising the primary component and one or more impurities. One such process includes: (a) passing the feed gas through a first adsorption bed to remove one or more impurities; (b) conducting a PSA cycle in the first bed; (c) separately passing effluent gases from the first bed into at least two separate tanks for subsequent purging and pressurization of the beds; (d) storing a gas mixture in the first of the tanks containing the primary component in a concentration higher than the concentration of the primary component in the gas mixture in the second of the tanks; (e) refluxing the mixture of the primary component from the second tank in the first adsorption bed during the regeneration steps therein; (f) refluxing the mixture of the primary component from the first tank in the first adsorption bed during the regeneration steps therein; (g) simultaneously and non-concurrently performing steps (a) to (f) in a second bed; and (h) recovering the product gas stream.
U.S. Pat. No. 6,340,382 B1 relates to a PSA process for purifying a synthesis gas stream containing from 60 to 90 mole % hydrogen and impurities such as C 02, CH 4, N 2, and CO. The PSA process of this disclosure further provides a method of adsorbing substantially all of the nitrogen and other contaminants from the feed gas stream; wherein the feed stream is passed at superatmospheric pressure through a plurality of adsorbent beds and each adsorbent bed contains at least a CaX, LiA, LiX or calcium containing mixed cation zeolite having a SiO 2 /Al 2 , O 3 mole ratio of 2.0–2.5. Such process involves sequentially pressurizing, depressurizing, purging and repressurizing the adsorbent beds with product hydrogen, and recovering product hydrogen in purities of 99.9% or greater from the beds.
U.S. Pat. No. 6,402,813 B2 relates to a gas stream containing one or more gaseous impurities from the group formed by carbon dioxide, water vapor, H 25 , alcohols, SO 2 and C 1 –C 8 saturated or unsaturated, linear, branched or cyclic hydrocarbons which is brought into contact with several different porous carbon adsorbents, that is to say active carbons having different properties and characteristics. The gas is air, nitrogen, hydrogen produced by the reforming or cracking of ammonia or the combustion gas or fermentation gas.
U.S. Pat. No. 6,483,001 B2 relates to a PSA apparatus and process for the production of purified hydrogen from a feed gas stream containing heavy hydrocarbons (i.e., hydrocarbons having at least six carbons). The apparatus comprises at least one bed containing at least three layers. The layered adsorption zone contains a feed end with a low surface area adsorbent (20 to 400 m 2 /g) which comprises 2 to 20% of the total bed length followed by a layer of an intermediate surface area adsorbent (425 to 800 m 2 /g) which comprises 25 to 40% of the total bed length and a final layer of high surface area adsorbent (825 to 2000 m 2 /g) which comprises 40 to 78% of the total bed length.
U.S. Pat. No. 6,027,549 relates to a process for adsorbing carbon dioxide from a carbon dioxide containing gas mixture comprising contacting the gas mixture with an activated carbon adsorbent having a density in the range of approximately 0.56 to 0.61 g/cc (35 to 38 lbs./ft 3 ) and adsorbing the carbon dioxide on the activated carbon adsorbent.
U.S. Pat. No. 5,294,247 relates to a process for recovering hydrogen from dilute refinery off gases using a vacuum swing adsorption process having a simultaneous cocurrent depressurization to provide a purge gas for another bed under the influence of a vacuum and countercurrent depressurization to vent void space gas and/or adsorbed gas to ambient.
U.S. Pat. No. 6,454,838 B1 relates to a PSA process includes providing a PSA apparatus having six beds, and equalizing a pressure of each of the six beds in four steps, wherein at all times during the process, at least one of the six beds is providing off gas. The process is particularly suitable for purifying hydrogen from a feed gas mixture containing hydrogen and at least one of the methane, carbon dioxide, carbon monoxide, nitrogen and water vapor.
U.S. Pat. No. 6,379,431 B1 relates to a PSA process including an adsorption apparatus having a plurality of beds and countercurrently purging at least two of the beds simultaneously throughout the process. The number of beds and number of pressure equalization steps are not particularly limited, but a ten-bed, four pressure equalization step process is advantageous. In addition, other ten-bed, four pressure equalization step processes are disclosed which do not countercurrently purge at least two of the beds simultaneously, but which have an average of at least two of the ten beds being simultaneously regenerated by simultaneously providing off gas from a feed end of each of the beds to an off gas line.
U.S. Pat. No. 5,912,422 relates to a process for the separation of the hydrogen contained in a gas mixture contaminated by carbon monoxide and containing at least one other impurity chosen from the group consisting of carbon dioxide and saturated or unsaturated, linear, branched or cyclic C 1 –C 8 hydrocarbons, comprising bringing the gas mixture to be purified into contact, in an adsorption region, with at least:
one first adsorbent selective at least for carbon dioxide and for C 1 –C 8 hydrocarbons and
one second adsorbent which is a zeolite of faujasite type exchanged to at least 80% with lithium, the Si/Al ratio of which is less than 1.5, in order to remove at least carbon monoxide (CO).
U.S. Pat. No. 6,210,466 B1 relates to a process which overcomes historical limitations to the capacity of PSA units for a wide variety of gas separations. Capacities in excess of about 110 thousand normal cubic meters per hour (100 million standard cubic feet per day) can now be achieved in a single integrated process train. The corresponding significant equipment reduction results from a departure from the accepted principle in the PSA arts that the length of the purge step must be equal to or less than the length of the adsorption step. By increasing the purge time relative to the adsorption step combined with supplying the purge gas for any adsorption bed in the train from one or more other adsorption beds and during the provide-purge step, the other adsorption beds simultaneously provide the purge gas to essentially all adsorption beds undergoing the purge step, that the single train can provide for significant increases in capacity with a minimum loss in recovery or performance. The benefit of this discovery is that very large-scale PSA units can now be constructed as a single train of equipment for a cost significantly lower than the cost of two or more parallel trains of equipment.
U.S. Pat. No. 5,753,010 relates to a method for increasing product recovery or reducing the size of steam methane reformer and pressure swing adsorption systems utilized for hydrogen production. A significant portion of the hydrogen in the PSA depressurization and purge effluent gas, which is otherwise burned as fuel in the reformer, is recovered and recycled to the PSA system to provide additional high purity hydrogen product. This is accomplished by processing selected portions of the depressurization and purge effluent gas in adsorbent membrane separators to increase hydrogen content for recycle to the PSA system. Remaining portions of the depressurization and purge effluent gas which contain lower concentrations of hydrogen are utilized for fuel value in the reformer.
U.S. Pat. No. 3,430,418 relates to an adiabatic pressure swing process for selectively adsorbing components such as carbon dioxide, water and light aliphatic hydrocarbons from admixture with hydrogen gas is provided by at least four adsorbent beds joined in a particular flow sequence.
U.S. Pat. No. 3,564,816 relates to a PSA process for separation of gas mixtures in which at least four adsorbent beds are joined so that the adsorbate loaded bed is pressure equalized with two other beds in staged sequence.
U.S. Pat. No. 6,558,451 B2 relates to a compact multiple bed PSA apparatus to produce a high concentration of oxygen efficiently and at minimum noise levels by using inactive pressurized adsorber beds to purge adsorbed nitrogen.
U.S. Pat. No. 6,428,607 B1 relates to a PSA process for the separation of a pressurized feed gas containing at least one more strongly adsorbable component and at least one less strongly adsorbable component. The process comprises (a) introducing the pressurized feed gas into a feed end of an adsorber bed containing one or more solid adsorbents which preferentially adsorb the more strongly adsorbable component and withdrawing from a product end of the adsorber bed a first adsorber effluent gas enriched in the less strongly adsorbable component, wherein the first adsorber effluent gas is utilized as final product gas; (b) terminating the introduction of the pressurized feed gas into the adsorber bed while withdrawing from the product end of the adsorber bed a second adsorber effluent gas enriched in the less strongly adsorbable component, wherein the pressure in the adsorber bed decreases while the second adsorber effluent gas is utilized as additional final product gas; (c) depressurizing the adsorber bed to a minimum bed pressure by withdrawing additional gas therefrom; (d) repressurizing the adsorber bed by introducing repressurization gas into the bed, wherein at least a portion of the repressurization gas is provided by pressurized feed gas; and (e) repeating steps (a) through (d) in a cyclic manner. No final product gas is required for purge or repressurization in the process cycle steps.
U.S. Pat. No. 5,084,075 relates to a method for recovering nitrogen from air in a three bed vacuum swing adsorption technique in which the beds are not rinsed with nitrogen gas before recovering a nitrogen recycle stream and a nitrogen product.
An object of the present invention is to provide a multiple bed PSA system, preferably a three bed PSA system, that can process a continuous impurity gas stream to produce a high purity gas component without the use of storage tanks for collecting void gases during pressure changing steps in the PSA cycle.
Another object of the present invention is to provide a compact three bed PSA system that can operate with continuous supply gas at lower adsorption pressures, lower bed size factor (bsf) and lower capital cost relative to prior art PSA processes.
Another object of the invention is to provide a novel three bed PSA system for the production of hydrogen from a continuous impure gas stream containing hydrogen as a component.
Other objects and advantages of the invention will be apparent from the following description taken in connection with the accompanying drawings.
BRIEF SUMMARY OF THE INVENTION
The invention provides a pressure swing adsorption process for the separation of a pressurized supply feed gas containing at least one more strongly adsorbable component and at least one less strongly adsorbable product gas component in a multiple bed system which comprises the continuous feeding of a supply gas into a feed end of an adsorber bed containing at least one solid adsorbent which preferentially adsorbs the more strongly adsorbable component and withdrawing the least strongly adsorbable product component from an exit end of the adsorber bed, producing in cycles by steps in which the continuous feeding of the supply gas in sequentially co-current direction through each of the adsorber beds to produce gas product using continuous feed gas, pressurization step, pressure equalization step, constant product gas step and purge step in the PSA cycle.
The product gas of the process is preferably hydrogen although the process can also be extended to other separation processes such as helium purification, natural gas upgrading, CO 2 production from synthesis gas or other sources containing CO 2 in the supply feed or in other PSA processes for coproduction of H 2 and CO. One of the novel features of the invention is the use of a continuous feed supply gas in a multiple bed PSA system, preferably a three bed H 2 PSA system, that utilizes shorter beds having a lower adsorption pressure with an optimum ratio of product pressurization to adsorption pressure ranges from about 0.20 to about 0.35 for adsorption pressure from 20 psig to 900 psig from a 12-step cycle and 50 psig to 900 psig for other cycle steps. The above optimum amount of product pressurization is required to minimize bed size factor (bsf) in the production of high purity hydrogen at high recoveries. The amount of product pressurization is defined by dividing the change in bed pressure during the product pressurization step by the adsorption pressure.
DETAILED DESCRIPTION OF THE INVENTION
In a first and preferred embodiment of the invention, the novel PSA system employs a twelve-step three adsorbent bed PSA cycle having two pressure equalization steps in addition to purging and product pressurization steps. The PSA process also utilizes a continuous supply gas feed without the use of storage tanks and utilizes a product pressurization step before a high pressure equalization step. The three bed PSA cycle has lower bed size factor than prior art PSA processes.
Another embodiment of the invention utilizes a nine-step three bed PSA system having a high-pressure equalization step overlapped with feed pressurization step without a product pressurization step.
Another embodiment of the invention utilizes a nine-step three bed PSA system having a product pressurization step without a high pressure equalization step.
A primary benefit of the twelve-step three bed hydrogen PSA system in comparison to either embodiments of the nine-step three bed system, is reduction in the bed size factor.
Suitable adsorbents such as activated carbons with different bulk densities and other zeolitic materials such as Li—X zeolite, CaX (2.0), etc. can be used in the three bed PSA separation process without deviating from the scope of the invention. For example, instead of using VSA6 zeolite, the three bed PSA process could also use CaX (2.0) and naturally occurring crystalline zeolite molecular sieves such as chabazite, erionite and faujasite. Furthermore, zeolite containing lithium/alkaline earth metal A and X zeolites (Chao et al., U.S. Pat. Nos. 5,413,625; 5,174,979; 5,698,013; 5,454,857 and 4,859,217) may also be used in this invention.
Also, each of the layered adsorbent zones in each of the PSA beds could be replaced with layers of adsorbents of the same type. For example, the single layer of zeolite in each bed could be replaced with multiple layers of different adsorbents (e.g., VSA 6 could be replaced by a first layer of 13 X with VSA6 on top). In addition, the zeolite layer could be substituted by a composite adsorbent layer containing different adsorbent materials positioned in separate zones in which temperature conditions favor adsorption performance of the particular adsorbent material under applicable processing conditions in each zone. Further details on composite adsorbent layer design is given by Notaro et al., U.S. Pat. No. 5,674,311.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is described with reference to the appended figures.
FIG. 1 is a schematic flow diagram for a three bed PSA system in accordance with the invention.
FIG. 2 is a series of schematic illustrations of adsorption beds as they undergo each step of the first embodiment of a twelve-step three bed PSA system of the present invention.
FIG. 3 is process pressure profiles of a twelve-step three bed PSA system.
FIG. 4 is a plot of bed size factor versus bed pressure change during product pressurization/adsorption pressure for a three bed PSA system.
FIG. 5 is a series of schematic illustrations of adsorption beds as they undergo each step of the second embodiment of a nine-step three bed PSA system of the present invention.
FIG. 6 is a series of schematic illustrations of adsorption beds as they undergo each step of the third embodiment of a nine-step three bed PSA system of the present invention.
FIGS. 1 and 2 show a twelve-step three bed PSA system comprising three adsorber beds, 17 ON/OFF valves, 5 control valves (CV) and associated piping and fittings. The control valves are used to control the flow rate or pressure during certain steps in the process; CV- 1 controls the flow rate out of the bed during the first blowdown; CV- 2 controls the rate at which the beds provide purge; CV- 3 controls the rate at which the beds equalize; CV- 4 controls the rate at which the beds receive product pressurization gas; and CV- 5 maintains the bed at constant pressure during product production.
An example of a PSA process using the three bed PSA process of this invention is shown on FIGS. 1–3, having operation conditions shown in Table 1 and the valve switching logic of Table 2. The results shown below were obtained from a PSA pilot plant using a feed mixture on a dry basis: 77.4% H 2 , 19.24%, CO 2 , 0660.66% CO, 1.99% CH 4 and 0.70 N 2 . Also in the table, total bed size factor is the total quantity of adsorbents per ton per day of H 2 produced.
TABLE 1
PSA Process Performance and Operating Conditions.
Cycle time(s):
480
Adsorbent in first layer of Bed
Alumina
Amount of alumina (lb/TPD H 2 ):
1.053 × 10 3
Adsorbent in second layer of bed:
activated carbon
Amount of activated carbon (lb/TPD H 2 ):
2.804 × 10 3
Adsorbent in third layer of bed:
VSA6 zeolite
Amount of zeolite (lb/TPD H 2 ):
2.063 × 10 3
High Pressure:
9.324 × 10 2 kPa
Low Pressure:
1.360 × 10 2 kPa
Feed Flux (Kmol/s · m 2 )
1.5814 × 10 −2
Hydrogen Purity:
99.99%
Hydrogen Recovery:
75%
Total Bed Size Factor (lb/TPD H 2 )
5.920 × 10 3
Temperature
311.2 K
TPD = ton (2000 lb)
Pa = S.I. unit for
atm. = 1.01325 bars = 101.32
pressure (1.0)
TABLE 2
Valve Firing Sequence for twelve-step three bed hydrogen PSA Process
Step
1
2
3
4
5
6
7
8
9
10
11
12
Step
90
24
35
11
90
24
35
11
90
24
35
11
Times
(seconds)
Bed 1
AD1
AD2
AD3
ED1
PPG
ED2
BD1
BD2
PG
EUI
PP
EU2/FD
Bed 2
PG
EUI
PP
EU2/FD
AD1
AD2
AD3
ED1
PPG
ED2
BD1
BD2
Bed 3
PPG
ED2
BDI
BD2
PG
EUI
PP
EU2/FD
ADI
AD2
AD3
EDI
Valve No.
1
O
O
O
C
C
C
C
C
C
C
C
O
2
C
C
C
O
O
O
O
C
C
C
C
C
3
C
C
C
C
C
C
C
O
O
O
O
C
4
C
C
C
C
C
C
O
O
O
C
C
C
5
O
C
C
C
C
C
C
C
C
C
O
O
6
C
C
O
O
O
C
C
C
C
C
C
C
7a
C
C
C
C
0
0
C
C
C
C
C
0
7b
C
C
C
C
C
C
C
C
C
C
0
C
7c
C
C
C
0
C
C
C
C
0
0
C
C
8a
0
0
C
0
C
C
C
0
0
0
C
C
8b
C
C
0
C
C
C
C
C
C
C
C
C
9a
0
0
C
C
0
0
C
0
C
C
C
0
9b
C
C
C
C
C
C
0
C
C
C
C
C
10
0
0
0
C
C
C
C
C
C
C
C
C
11
C
C
C
C
0
0
0
C
C
C
C
C
12
C
C
C
C
C
C
C
C
0
0
0
C
13
0
C
C
0
0
C
C
0
0
C
C
0
AD: Adsorption/Product Production
PG: Receive Purge
ED1: First Equalization Down
EU1: First Equalization Up
PPG: Provide Purge Gas
EU2: Second Equalization Up
ED2: Second Equalization Down
PP: Product Pressurization Using R Gas (RG)
BD: Blowdown
FD: Feed Pressurization
Referring to FIGS. 1–3 and Table 2, the three bed twelve step PSA process is now described over one complete PSA cycle.
Step No. 1 : Feed gas is introduced to the bottom of Bed 1 while hydrogen product is taken from the top (AD 1 ). Bed 2 is receiving purge gas from Bed 3 . At start of step 1 , the pressure in Bed 1 is close to adsorption pressure. Valve 1 is open to allow feed into the bottom of Bed 1 and Valve 10 is open to allow product hydrogen out of the top of Bed 1 . However, product production does not occur until Bed 1 reaches the adsorption pressure. At this point CV- 5 opens and controls the pressure in the bed for constant pressure product production. Valves 8 a and 9 a are open to allow purge gas to flow from Bed 3 to Bed 2 through Control Valve CV- 2 . Valves 5 and 13 remain open to allow purge gas to flow out of the bottom of Bed 2 .
Step No. 2 : Bed 1 is in the second adsorption step (AD 2 ). Bed 3 undergoes a second equalization down while Bed 2 receives gas from Bed 3 and undergoes a first equalization up. At the start of step 2 , Valves 1 and 10 remain open to allow product production to continue from Bed 1 . Valves 8 a and 9 a also remain open to allow equalization to occur between Beds 2 and 3 . However, the equalization gas flows through Control Valve CV- 3 instead of CV- 2 . Valves 5 and 13 close.
Step No. 3 : Bed 1 is in the third adsorption step (AD 3 ). Bed 2 receives product pressurization gas from the product manifold. Bed 3 undergoes a first counter-current blowdown. At the start of step 3 , Valves 1 and 10 remain open to allow product production to continue from Bed 1 . Valves 8 a and 9 a close. Valve 8 b opens to allow product gas to pressurize Bed 2 . Valve 6 opens to allow Bed 3 to undergo counter-current blowdown. Valve CV- 1 controls the flow rate of the blowdown gas.
Step No. 4 : Bed 1 undergoes a first equalization down (ED 1 ) while Bed 2 receives gas from Bed 1 and undergoes a second equalization up overlapped with feed pressurization. Bed 3 undergoes a second counter-current blowdown. At the start of step 4 , Valves 1 , 8 b and 10 close. Valves 7 c and 8 a open to allow equalization to occur between Beds 1 and 2 through Control Valve CV- 3 . Valve 2 opens to allow feed pressurization in Bed 2 . Valve 13 opens and Valve CV- 1 closes.
Step No. 5 : Bed 1 provides purge gas to Bed 3 (PPG) while Bed 2 undergoes the first adsorption step. At the start of step 5 , Valves 7 c and 8 a close. Valve 2 remains open to allow feed gas into the bottom of Bed 2 and Valve 11 is open to allow product hydrogen out of the top of Bed 2 . However, product production does not occur until Bed 2 reaches the adsorption pressure. At this point CV- 5 opens and controls the pressure in the bed for constant pressure product production. Valves 7 a and 9 a are open to allow purge gas to flow from Bed 1 to Bed 3 through Control Valve CV- 2 . Valves 6 and 13 remain open to allow purge gas to flow out of the bottom of Bed 3 .
Step No. 6 : Bed 1 undergoes a second equalization down (ED 2 ) while Bed 3 receives gas from Bed 1 and undergoes a first equalization up. Bed 2 undergoes the second adsorption step. At the start of step 6 , Valves 2 and 11 remain open to allow product production to continue from Bed 2 . Valves 7 a and 9 a also remain open to allow equalization to occur between Beds 1 and 3 . However, the equalization gas flows through Control Valve CV- 3 instead of CV- 2 . Valves 6 and 13 close.
Step No. 7 : Bed 1 undergoes the first counter-current blowdown (BD 1 ). Bed 2 undergoes the third adsorption step while Bed 3 receives product pressurization gas from the product manifold. At the start of step 7 , Valves 2 and 11 remain open to allow product production to continue from Bed 2 . Valves 7 a and 9 a close. Valve 9 b opens to allow product gas to pressurize Bed 3 . Valve 4 opens to allow Bed 1 to undergo counter-current blowdown. Valve CV- 1 controls the flow rate of the blowdown gas.
Step No. 8 : Bed 1 undergoes the second counter-current blowdown (BD 2 ). Bed 2 undergoes a first equalization down while Bed 3 receives gas from Bed 2 and undergoes a second equalization up overlapped with feed pressurization. At the start of step 8 , Valves 2 , 9 b , and 12 close. Valves 8 a and 9 a open to allow equalization to occur between Beds 3 and 2 through Control Valve CV- 3 . Valve 3 opens to allow feed pressurization in Bed 3 . Valve 4 remains open and Bed 1 continues to undergo counter-current blowdown. Valve 13 opens and Valve CV- 1 closes.
Step No. 9 : Bed 1 receives purge gas from Bed 2 (PG) while Bed 3 undergoes the first adsorption step. At the start of step 9 , Valve 9 a closes. Valve 3 remains open to allow feed gas into the bottom of Bed 3 and Valve 12 is open to allow product hydrogen out of the top of Bed 3 . However, product production does not occur until Bed 3 reaches the adsorption pressure. At this point CV- 5 opens and controls the pressure in the bed for constant pressure product production. Valve 7 c opens and Valve 8 a remains open to allow purge gas to flow from Bed 2 to Bed 1 through Control Valve CV- 2 . Valves 4 and 13 remain open to allow purge gas to flow out of the bottom of Bed 1 .
Step No. 10 : Bed 1 undergoes a first equalization up (EU 1 ) while Bed 2 provides gas to Bed 1 and undergoes a second equalization down. Bed 3 undergoes the second adsorption step. At the start of step 10 , Valves 3 and 12 remain open to allow product production to continue from Bed 3 . Valves 7 c and 8 a also remain open to allow equalization to occur between Beds 2 and 1 . However, the equalization gas flows through Control Valve CV- 3 instead of CV- 2 . Valves 4 and 13 close.
Step No. 11 : Bed 1 receives product gas from the product manifold for product pressurization. Bed 2 undergoes the first counter-current blowdown. Bed 3 undergoes the third adsorption step. At the start of step 11 , Valves 3 and 12 remain open to allow product production to continue from Bed 3 . Valves 7 c and 8 a close. Valve 7 b opens to allow product gas to pressurize Bed 1 . Valve 5 opens to allow Bed 2 to undergo countercurrent blowdown. Valve CV- 1 controls the flow rate of the blowdown gas.
Step No. 12 : Bed 1 undergoes a second equalization up with overlapped feed pressurization (EU 2 /FD) while Bed 3 provides gas to Bed 1 and undergoes a first equalization down. Bed 2 undergoes the second counter-current blowdown. At the start of step 12 , Valves 3 , 7 b , and 12 close. Valves 7 a and 9 a open to allow equalization to occur between Beds 3 and 1 through Control Valve CV- 3 . Valve 1 opens to allow feed pressurization in Bed 3 . Valve 5 remains open and Bed 2 continues to undergo counter-current blowdown. Valve 13 opens and Valve CV- 1 closes.
Note from FIG. 2 and Table 2 that the three beds operate in parallel, and during ⅓ of the total cycle time one of the beds is in the adsorption step, while the other beds are either undergoing purging, equalization, countercurrent blowdown, and product pressurization.
Based on pilot plant and PSA simulation results, there is an optimum amount of product pressurization and high pressure equalization gas required to achieve high H 2 recovery in the three bed PSA process of this invention. Also, since the product pressurization step (see FIG. 2 ) is before the high pressure equalization step (ED 1 ), then using too much product pressurization gas will result in a much reduced quantity of gas recovered in the high pressure equalization step. Because the driving force (pressure gradient) is reduced with increasing amount of gas used for product pressurization, there is an optimum quantity of product pressurization gas and high pressure equalization gas to be used in the PSA process in order to achieve high H 2 recovery (low bed size factor). FIG. 4 shows a plot of the bed size factor (bsf) for various amounts of product pressurization gas used in the PSA process of FIGS. 1 and 2 .
Referring to FIG. 4 , Points B-E show data for the twelve step PSA process shown in FIGS. 1 and 2 when the amount of product pressurization gas used in the PSA process is varied. Point E shows the optimum amount of product pressurization to achieve the minimum bed size factor (bsf). In FIG. 4 , the amount of product pressurization is defined by dividing the change in bed pressure during the product pressurization step by the adsorption pressure.
Some novel features of the 12-step three bed PSA system are the use of two pressure equalization steps in addition to purging and product pressurization steps, use of the product pressurization step before the pressure equalization step, use of continuous supply feed gas and a constant pressure product gas step.
In the limiting cases where no product pressurization or high pressure equalization is used, the PSA process of FIG. 2 is reduced to two different 9-step processes. For example, if steps 3 , 7 and 11 are eliminated (i.e., no product pressurization case) from the twelve step PSA cycle in FIG. 2 , then the resulting PSA cycle is reduced to a 9-step cycle shown in FIG. 5 . This cycle ( FIG. 5 ) has a high pressure equalization step but has no product pressurization step. This is Point A on FIG. 4 . Alternatively, if steps 4 , 8 and 12 are eliminated (i.e., no high pressure equalization), then the resulting cycle is reduced to a 9-step PSA cycle shown in FIG. 6 . This cycle ( FIG. 6 ) has a product pressurization step but has no high pressure equalization step. This is Point F on FIG. 4 . In accordance to the teachings of this invention, the three bed PSA process depicted in FIGS. 1 and 2 has enhanced H 2 recovery (lower bed size factor) when the ratio of product pressurization to adsorption pressure ranges from 0.20 to 0.35. In addition, this optimum ratio of product pressurization to adsorption pressure holds for adsorption pressures from 20 psig to 900 psig for the twelve-step PSA system and 50 psig to 900 psig for the 9-step PSA system.
It will be understood that other changes may be made in the parameters of the PSA system hereof without departing from the invention. Accordingly, it is intended that the scope of this invention should be determined from the claims appended hereto. | A three-bed pressure swing adsorption system providing a constant continuous supply gas, preferably containing a hydrogen component, in a multi-step and preferably in a twelve-step, process cycle that can produce a purified gas product, preferably hydrogen, on a constant flow. | 1 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of Provisional Application No. 62/292,777, filed Feb. 8, 2016.
TECHNICAL FIELD
[0002] The current document is directed to the object-orientation methods and devices and, in particular, to devices and methods that employ the devices to facilitate manual orientation of various types of connectors, keys, and other such objects that are pushed or inserted into complementary connectors, slots, and other receptacles.
BACKGROUND
[0003] Many different types of connectors, keys, plugs, cards, and other objects are commonly used in the modern world. For example, many different types of power and data-transmission cables terminate in a connector or adapter that is complementary to a connector or port on a power supply, power source, and/or data source. When a computer user, for example, wishes to connect the computer to a power source, the computer user pushes the connector at the end of a power cable already connected to the power source into a complementary connector or port on the surface of the computer. Similarly, when the computer user wishes to connect the computer to a peripheral electronic device, the computer user plugs the connectors at each end of a data-transmission cable into complementary connectors or ports of the computer and peripheral device. There are many different types of electrical connectors, including the universal serial bus (“USB”), FireWire, i.Link, high-definition multimedia interface (“HDMI”), and a variety of different multi-pin connectors used to connect display terminals, keyboards, and other peripheral devices to desktop computers. In certain cases, a connector, such as a USB connector, can be used both for connecting a computer or cell phone to a power supply as well as for connecting the computer or cell phone to a data source. Various types of ATM cards and smartcards are inserted into card slots to authorize financial transactions by exchanging data with centralized computer systems within financial institutions. Keys are commonly used to unlock house doors, bicycle locks, and other types of locks as well as to operate the ignition system of automobiles and other vehicles. These are a few examples of the many different types of objects that are manipulated by human beings to engage with complementary connectors, ports, slots, or other receptacles for many different purposes.
[0004] In many cases, the objects that are manipulated by human beings to engage with complementary connectors and receptacles include engagement features with less symmetry than the object handle. For example, a USB connector has a bilaterally symmetric cross-section, but because the top surface is wider than the lower bottom surface, the USB connector lacks a proper rotation axis parallel to the direction of insertion and removal from a complementary port. As a result, the USB connector must be properly rotationally oriented with the top wider surface matching a wider opening of the port in order to successfully insert the USB connector into a complementary USB port. Similarly, a key blank often includes a shaft with two orthogonal mirror-plane symmetry parallel to the central, long central axis of the shaft. However, when the key blank is cut to create the irregular pattern of teeth along one edge of the shaft, at least one of the mirror-plane symmetry elements is lost, and the resulting key is less symmetrical than the key blank. Many ATM cards and smartcards of a magnetic stripe on only one of the two surfaces parallel to one set of edges. In many cases, the ATM card or smartcard must be correctly oriented for the magnetic stripe to align with a card reader into which the ATM card or smartcard is inserted in order to authorize a transaction. This is also the case for credit cards used in gas pumps and grocery-store credit-card readers. However, in all of the above-mentioned cases, the handle or surfaces of the object grasped by a human user commonly has greater symmetry than the engagement feature that needs to be inserted into a complementary device or receptacle. For example, a USB connector often emerges from a roughly rectangular plastic plug. In many cases, the rectangular plastic plug has a 2-fold or 4-fold symmetry axis parallel to the cable, on one side, and the long axis of the USB, on the other side. To a human user, the rectangular plastic plug has the same apparent shape and orientation when rotated about a 2-fold symmetry axis by 180°. However, the USB connector, or engagement feature, does not have a 2-fold or 4-fold symmetry axis parallel to that of the rectangular plastic plug, and therefore has a different shape and orientation when rotated about an axis parallel to the long symmetry axis of rectangular plastic plug by 180°. Often, particularly for older people, it is difficult to visually ascertain the orientation of the USB connector and, as a result, users often repeatedly attempt to insert a USB connector with an incorrect orientation into a USB port. This can result in time-consuming fumbling, annoyance, and even damage to the USB connector, USB port, or both. Similarly, when an ATM user is rushed or when the ATM machine is poorly lighted, the ATM user may inadvertently insert the ATM card into the ATM-card reader in one of several different incorrect orientations, again resulting in time-consuming fumbling and multiple attempts, annoyance, and possibly increased wear and damage to the ATM card, in particular to the magnetic stripe on the surface of the ATM card. There are probably few, if any, people who have never experienced the annoyance of incorrectly inserting keys into the key slots of house doors or vehicle-ignition subsystems. In both the case of the ATM card and keys, the object surface grasped by the user has greater apparent symmetry than that the engagement feature that needs to be properly oriented before insertion into the complementary receptacle. A user cannot tell, by feel alone, whether or not the engagement feature of the object is properly oriented, because there are one or more alternative positions in which the orientation of the handle or grasped surface feels the same, but in which the engagement feature is improperly oriented. In many cases, even when the object is in full view, a user may nonetheless fail to properly oriented the engagement feature of the object for insertion into the complementary receptacle do to the small size of the engagement feature or lack of clear orientation indications on the slot, connector, port, or other receptacle into which the engagement feature needs to be inserted.
[0005] While a seemingly relatively insignificant problem, the frequent inability of human users to properly orient connectors, keys, cards, and other such devices prior to insertion into a complementary connector, slot, or other receptacle, represents a significant inefficiency in human/machine interaction as well as a significant source of wear and damage to the mechanical, electromechanical, and electro-optical-mechanical systems accessed by connectors, keys, cards, and other such devices.
SUMMARY
[0006] The current document is directed to methods and devices that facilitate object orientation. In particular, the current document is directed to methods and devices that facilitate tactile orientation of objects, such as connectors, keys, cards, and other objects that are manipulated by human users for insertion into complementary connectors, slots, and other receptacles. In addition to facilitating tactile orientation of objects, the devices and additionally provide mechanical advantage for objects insertion and removal and may additionally provide visual orientation indications, and other indications, to human users. The currently disclosed devices are tangible, physical objects or features that, when held, felt, and/or manipulated by human users, provide a tactile indication of the orientation of an engagement feature of an object is inserted into a complementary connector, slot, port, or other receptacle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1 illustrates a first implementation of the currently disclosed tactile orientation devices.
[0008] FIGS. 1A-D illustrates symmetry elements of components of the USB cable, discussed above with reference to FIG. 1 , with and without the tactile orientation device.
[0009] FIG. 2 illustrates a second implementation of the tactile orientation devices disclosed in the current document.
[0010] FIG. 3 illustrates a third implementation of the tactile orientation devices disclosed in the current document.
[0011] FIG. 4 illustrates a fourth implementation of the tactile orientation devices disclosed in the current document.
[0012] FIG. 5 illustrates a fifth implementation of the tactile orientation devices disclosed in the current document.
[0013] FIG. 6 illustrates a sixth implementation of the tactile orientation devices disclosed in the current document.
[0014] FIG. 7 illustrates a seventh implementation of the tactile orientation devices disclosed in the current document.
DETAILED DESCRIPTION
[0015] FIG. 1 illustrates a first implementation of the currently disclosed tactile orientation devices. FIG. 1 shows a portion of a USB cable 100 that includes a USB connector 102 , a rectangular connector body 104 from which the USB connector extends, and an electric cable 106 that includes wires and/or other conductive elements at interconnect through the rectangular connector body to the USB connector. As shown in FIG. 1 , a tactile orientation device 108 has been included on the top surface of the rectangular connector body. The tactile orientation device is a cylindrical-section or conical-section shape with a planar or slightly curved top disk-shaped surface 110 and a side wall 112 . The tactile orientation device may be molded together with the rectangular connector body, separately manufactured and permanently affixed to the rectangular connector body, or, in certain implementations, may be semi-permanently affixed to the retailer connector body, allowing the tactile orientation device to be repositioned or removed. FIGS. 1A-D illustrates symmetry elements of components of the USB cable, discussed above with reference to FIG. 1 , with and without the tactile orientation device. As discussed above, in the background section, the rectangular connector body 104 of the USB cable, without the tactile orientation device, has greater symmetry than the USB connector 102 . The cable has even greater symmetry than both the rectangular connector body and the USB connector. The symmetry elements for these three components are shown in FIGS. 1A-C . The USBE connector 102 has 2m symmetry, as shown in FIG. 1A , with a vertical 2-fold symmetry axis 120 and two vertical mirror planes 122 and 124 . There is no proper symmetry rotation axis perpendicular to the 2-fold axis 120 and thus no proper rotation axis parallel to the direction in which the USB connector is inserted or removed from a complementary USB port. By contrast, the rectangular connector body 104 without the tactile orientation device 110 , as shown in FIG. 1B , has a 4-fold symmetry axis 126 parallel to the central axes of the cable 106 , rectangular connector body 104 , and USB connector 102 , which defines the direction in which the USB connector is inserted or removed from a complementary USB port. This, of course, assumes that the width and height of the rectangular connector body are identical. The rectangular connector body therefore would feel the same, and have the same visual appearance, when rotated by 900, 180°, and 270° about the 4-fold symmetry axis. Therefore, there are three orientations of the rectangular connector body without the tactile orientation device equivalent to the orientation shown in FIG. 1 in which the USB connector is improperly oriented with respect to a complementary port. The rectangular connector body without the tactile orientation device has 4 mm symmetry and has two additional 2-fold symmetry axes 128 - 129 and three mirror planes 130 - 132 . The electric cable 106 , as shown in FIG. 1C , has an infinite-fold symmetry axis 134 corresponding to the central, long axis of the cable when the cable is not bent or curved, as well as an infinite number of mirror planes parallel to, and coincident with, the n-fold axis, not shown in FIG. 1C , and a perpendicular mirror plane 136 . The cable has n/mm symmetry. A user holding the cable and rectangular connector body cannot tell, by feel, whether the USB connector is in the orientation shown in FIG. 1 or in an orientation obtained by a 900, 180°, or 270° rotation about the 4-fold symmetry axis 126 . This is a result of the rectangular connector body and cable having greater symmetry than the USB connector.
[0016] The presence of the tactile orientation device removes the 4-fold symmetry axis of the rectangular connector body, as shown in FIG. 1D . The rectangular connector body with the tactile orientation device has 2m symmetry—the same symmetry as the USB connector. By reducing the symmetry of the rectangular connector body, the tactile orientation device allows a human user to determine the orientation of both the rectangular connector body and the USB connector by feel. When the tactile orientation device is vertically oriented, the USB connector has the orientation shown in FIG. 1 . By feel alone, a human user can properly orient the USB connector for insertion into a complementary connector or port. In addition, the tactile orientation device 108 provides a rigid surface roughly perpendicular to the direction of USB-connector insertion to provide a mechanical advantage to a user when inserting or removing the USB connector from a complementary connector or port.
[0017] FIG. 2 illustrates a second implementation of the tactile orientation devices disclosed in the current document. The tactile orientation device 202 in this implementation has a spherical surface, different in shape and feel from the tactile orientation device 108 shown in FIG. 1 . Tactile orientation device 202 may include a light source to provide an additional, visual indication of the orientation of the rectangular connector body 204 and USB connector 206 . The light source may be included within the tactile orientation device or within the rectangular connector body. The light source may be a light-emitting diode (“LED”) that is powered from the same power source that powers the USB connector. Alternatively, the light may be emitted by fluorophores or phosphorescent materials incorporated within the tactile orientation device. In additional implementations, the tactile orientation device has a reflective surface or colored to provide additional visual cues to human users. In the case of an LED light source, the light may not only provide a visual indication of the orientation of the rectangular connector body and USB connector, but may also facilitate aligning the USB connector with the complementary USB port in low-illumination environments.
[0018] FIG. 3 illustrates a third implementation of the tactile orientation devices disclosed in the current document. In this implementation, the tactile orientation device 302 has a cylindrical surface 304 . The surface is transparent and magnifies a printed mark or label 306 below the cylindrical surface to produce and easily read image 308 of the label or marking coincident with the spherical surface. Thus, various implementations of the tactile orientation devices disclosed in the current document can include markings, labels, numbers, or other visual indicators to facilitate identification of the type of connector, matching the connector to a complementary port, also labeled with the indication, and/or indicating other characteristics and features of the connector and/or the device or system to which the connector is inserted.
[0019] FIG. 4 illustrates a fourth implementation of the tactile orientation devices disclosed in the current document. In this implementation, the tactile orientation device is a depression 402 in the top surface 404 of the rectangular connector body 406 . As with the protruding tactile orientation devices shown in FIGS. 1-3 , tactile orientation device 402 breaks the otherwise 2-fold or 4-fold symmetry of the rectangular connector body along the length wise, central axis so that a user can determine the orientations of the rectangular connector body and the USB connector 408 by feel, alone.
[0020] FIG. 5 illustrates a fifth implementation of the tactile orientation devices disclosed in the current document. The tactile orientation device 502 shown in FIG. 5 has an arrow-like shape that conveys directional information to a user. A raised triangular feature 504 on the top surface 506 of the tactile orientation device 502 can facilitate tactile determination of the directional orientation of the tactile orientation device 502 and may provide additional information to a user holding or touching the tactile orientation device and the object to which it is mounted or within which it is incorporated. In FIG. 5 , the surface of the raised triangular feature is stippled to indicate that the surface of the raised triangular feature may have additional texture, small-sized features, or other characteristics and properties that provide additional information to a user as well as facilitating determination of the orientation of the tactile orientation device. For example, different surface textures, small-grain features, and other characteristics may indicate different types of objects to which the tactile orientation feature is mounted or within which the tactile orientation device is incorporated. As with previously described tactile orientation features, the raised feature may provide mechanical advantage for manipulating the object to which the tactile orientation device is mounted or within which the tactile orientation device is incorporated. The tactile orientation feature may be mounted to an underlying object using adhesive, a pin or post interconnect, a ball-and-socket press fit, or by magnetic attraction, in which case one or more magnets are incorporated within either or both of the tactile orientation device and the object to which the tactile orientation device is mounted or within which the tactile orientation device is incorporated.
[0021] FIG. 6 illustrates a sixth implementation of the tactile orientation devices disclosed in the current document. In FIG. 6 , the tactile orientation device 602 is a star-shaped and is mounted to a power-cable plug 604 . The plug has a first, wider connector 606 and a second narrower connector 608 , and must be properly oriented for insertion into an outlet with two differently sized apertures for the connectors. When a user feels the star-shaped tactile orientation device 602 at the top of the plug, the user knows that the plug is properly oriented for insertion into an outlet.
[0022] FIG. 7 illustrates a seventh implementation of the tactile orientation devices disclosed in the current document. In FIG. 7 , a tactile orientation device 702 with a cylindrical surface is mounted to, or incorporated on, the surface of a key 704 . This is tactile orientation device allows a user to differentiate, by feel, the top side of the key 706 from the reverse bottom side 707 . When a user feels the tactile orientation device on the right-hand side of the key, when the key handle is vertically oriented, the user knows that the teeth of the key are pointed downward. This allows a user to correctly orient the key prior to insertion into a key slot.
[0023] In addition to facilitating orientation of an engagement future of an object, the currently disclosed tactile orientation devices may additionally provide mechanical stability and strain relief to a cable/plug/connector assembly. This mechanical stability and strain relief may decrease or eliminate various types of wear and damage otherwise suffered by the cable/plug/connector assembly. The above-discuss tactile orientation devices each includes a single piece or feature. In alternative implementations, the tactile orientation device may include multiple features arranged in a pattern on one or more surfaces of an object. As mentioned briefly, above, tactile orientation devices with different textures or other surface characteristics and/or with different easily distinguished shapes and sizes, can be used to allow users to differentiate, by feel, different types of devices, such as differentiating micro-USB B connectors from USB Mini-b connectors or between USB A type connectors and HDMI connectors. As also mentioned above, certain types of mechanical attachments allow tactile orientation devices to be reversibly attached to an object which, in turn, allows different types of tactile orientation devices to be mounted to various objects at different times. Tactile orientation devices may be rigid, semi-rigid, flexible, or pliable, depending on the type of object to which there are attached are within which they are incorporated as well as the types of use for the object and the types of manipulation commonly applied to the object. As discussed above, various types of visual cues, including lighting, labeling, numbering, coloring, and altering the surface reflectivity may be used to impart in this additional information to users.
[0024] Although the present invention has been described in terms of particular embodiments, it is not intended that the invention be limited to these embodiments. Modifications within the spirit of the invention will be apparent to those skilled in the art. For example, in one implementation, the tactile orientation devices on connector at each end of a cable may be complementary Velcro™ strips that have an additional use of joining the ends of the rolled-up cable together when the cable is not being used. A similar implementation may use magnets. Such dual-use tactile orientation devices may also be used to securely store the cable when not in use. Many additional implementations are possible by varying the shapes, sizes, locations, textures, colors, reflectivities, and other characteristics of the tactile orientation devices and the materials from which they are fabricated.
[0025] It is appreciated that the previous description of the embodiments is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. | The current document is directed to methods and devices that facilitate object orientation. In particular, the current document is directed to methods and devices that facilitate tactile orientation of objects, such as connectors, keys, cards, and other objects that are manipulated by human users for insertion into complementary connectors, slots, and other receptacles. In addition to facilitating tactile orientation of objects, the devices and additionally provide mechanical advantage for objects insertion and removal and may additionally provide visual orientation indications, and other indications, to human users. The currently disclosed devices are tangible, physical objects or features that, when held, felt, and/or manipulated by human users, provide a tactile indication of the orientation of an engagement feature of an object is inserted into a complementary connector, slot, port, or other receptacle. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a material or composition which is useful in the manufacture of prototype elements, and more particularly, to a ceramic feedstock composition which may be used in a ribbon or filament deposition apparatus for the manufacture or building of prototype elements.
In U.S. Pat. No. 5,340,433 and U.S. Pat. No. 5,121,329, there is depicted a device or apparatus which is useful for the manufacture of prototype elements. The device feeds a filament of filled or unfilled polymer or other material through a discharge nozzle for deposition upon a platen. Either the nozzle or platen or both move in accord with a pre-programed pathway to enable the filament of material discharged from the nozzle of the device to form a prototype element. For example, gear shapes may be formed in this manner, though the particular shape formed is not a limiting feature of the invention. The subject matter of U.S. Pat. No. 5,340,433 and U.S. Pat. No. 5,121,329 is incorporated herewith by reference.
Various compositions and materials have been used or are disclosed for use in a process of the type depicted in the aforesaid U.S. Patents. Further, applicants herein are co-inventors with respect to advanced type apparatus useful in the creation of prototype elements using a filament deposition technique.
One of the challenges with respect to such methods and procedures is to devise a ceramic or other feedstock composition which will be especially useful in the creation of prototype elements and low volume production parts. Such a feedstock material should have adequate hardenability and toughness when formed into a desired element. The feedstock material should also be capable of use in apparatus of the type described. Such materials should also be subject to binder removal and sintering so that the element created utilizing the process may acquire both high strength and sintered density (95% of theoretical) enabling it to be used in a test or low volume ceramic parts production environment. Thus there has remained a need to provide an improved feedstock composition useful for the manufacture of prototype elements using ribbon deposition type apparatus and techniques.
SUMMARY OF THE INVENTION
Briefly, the present invention comprises a ceramic or metal feedstock composition for the manufacture of prototype elements using a filament or ribbon deposition apparatus wherein the composition comprises the combination of the four primary materials including:
(a) a ceramic or metal powder or powder mix;
(b) an ethylenejacrylate based copolymer binder (i.e. polyethylene-co-ethyl acrylate, polyethylene-co-butyl acrylate);
(c) wax (i.e. microcrystalline polyethylene wax, paraffin wax, beeswax, carnauba wax, amide wax, or combinations thereof); and
(d) liquid plasticizer.
These materials are mixed together and upon appropriate compounding, may be used in a prototype machine having a discharge nozzle which discharges a molten filament or ribbon in a pattern to form prototype elements. A wide variety of Group II, III, and IV and transition metal carbide, nitride, and oxide ceramic powders are useable in the invention as well as ferrous and nonferrous alloy powders. The ceramic or metal powder is typically ball milled either dry or in a solvent vehicle to disperse, deagglomerate, and uniformly mix the ceramic powders. Hexane is a preferred liquid vehicle for ball milling, but other liquids may be used. The hexane is then stripped from the material, e.g., by distillation, so that the ceramic powder remains. The powder is then mixed in combination with the other materials cited above. The combined materials have preferred ranges or amounts. The ceramic or metal powder, for example, comprises in the range of 75 to 93 weight % of the composition. The binder comprises 4.5 to 14 weight percent of the composition. The wax comprises 1.5 to 6 weight percent of the composition and the plasticizer comprises 1 to 5 weight percent of the composition. Typically, the green feedstock composition is fed into a prototype machine wherein a nozzle discharges a filament or ribbon in a specific pattern as described above. The prototype element is then debindered and sintered. In this manner a prototype element is created. It should also be noted that the feedstock may be utilized to manufacture a molded prototype product which is formed, fired and/or sintered.
Thus it is an object of the invention to provide an improved feedstock composition useful for the manufacture of prototype elements.
It is a further object of the invention to provide a ceramic feedstock composition which has minimal shrinkage and cracking densification of the debindered prototype element.
Yet another object of the invention is to provide a green ceramic feedstock composition which may be utilized to manufacture prototype elements wherein the elements are uniform in appearance and structure even following sintering thereof.
Another object of the invention is to provide a green ceramic feedstock composition which may be used to manufacture prototype elements wherein the fired elements have a density greater than 95% and possess high strength.
These and other objects, advantages and features of the invention will be set forth in the detailed description which follows.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The ceramic feedstock of the invention may be utilized in prototype machines of the type described in U.S. Pat. No. 5,340,433 and U.S. Pat. No. 5,121,329 and pending U.S. application Ser. No. 08/825,893 filed Apr. 2, 1997, entitled, "Method and Apparatus for In-Situ Formation of Three-Dimensional Solid Objects By Extrusion of Polymeric Materials." Other element forming machines may also be utilized in the practice of the invention. That is, the ceramic feedstock material may be used for feeding into a machine of the general nature described to thereby create a three-dimensional object from such feedstock.
The feedstock is comprised of four basic components: (1) ceramic or metal powders; (2) polyethylene-co-acrylate copolymer binder; (3) wax; and (4) liquid plasticizer. These four materials may be utilized with certain additional additives. For example, additives such as coloring agents may be utilized.
Advantageously, the powders which may be used to provide a feedstock include ceramic oxides, ceramic carbides, ceramic nitrides, ceramic borides, suicides, and metals or mixtures thereof. Preferred powders for use in that composition include aluminum oxide, barium oxide, barium titanate, beryllium, oxide, calcium oxide, cobalt oxide, chromium, oxide, dysprosium oxide and other rare oxides, lanthanum oxide, magnesium oxide, manganese oxide, niobium oxide, nickel oxide, aluminum phosphate and other phosphates, lead oxide, lead titanate, lead zirconate, silicon oxide and silicates, thorium oxide, titanium oxide and titanates, uranium oxide, yttrium oxide, yttrium aluminate, zirconium oxide and its alloys, boron carbide, iron carbide, hafnium carbide, molybdenum carbide, silicon carbide, tantalum carbide, titanium carbide, uranium carbide, tungsten carbide, zirconium carbide, aluminum nitride, boron nitride, silicon nitride, titanium nitride, uranium nitride, yttrium nitride, zirconium nitride, aluminum boride, hafnium boride, molybdenum boride, titanium boride, zirconium boride, molybdenum disilicide, as well as nickel, iron, chromium, cobalt, or their alloys, aluminum, beryllium, boron, copper, gold, hafnium, iridium, magnesium, manganese, molybdenum, niobium, palladium, platinum, rhenium, silver, tantalum, titanium, tungsten, zinc and zirconium.
The binder used in the invention is a homopolymer or copolymer of ethylene and acrylic acid or its ester. Examples of useable copolymer binders include polyethylene-co-ethylacrylate, polyethylene-co-butylacrylate and polybutylacrylate where polyethylene-co-ethylacrylate is the preferred polymer binder in this invention.
A wide variety of natural and synthetic waxes may be used in this formulation which impart dimensional rigidity upon cooling to the dispensed molten feedstock filament or ribbon material. These waxes include, but are not limited to, microcrystalline polyethylene wax, beeswax, paraffin wax, carnauba wax, Montan wax, and amide wax where microcrystalline polyethylene is the preferred material in the invention formulation.
A liquid plasticizer is also an ingredient of the invention and serves as a processing aid that reduces the melt viscosity of the feedstock composition, as well as increases the flexibility and toughness of its polymer binder component. These liquid plasticizers may be esters of fatty acids (i.e. butyl oleate), esters of phthalic acid (i.e. dibutyl phthalate, dioctylphthalate), or hydrocarbon oils (i.e. Heavy White Mineral Oil).
In any event, the feedstock formulation can be processed as a rod or as a small diameter (e.g. 0.070" diameter) filament forms. The rod feedstock is readily processed using high pressure extrusion heads of the type described in Application Ser. No. 08/825,893. Filament feedstock can be utilized in apparatus of the type disclosed in U.S. Pat. No. 5,340,433 and U.S. Pat. No. 5,121,329.
The filament feedstock is very flexible and will not fracture after repeated flexure. This phenomenon is observed despite the fact that the filament is greater than 50% by volume ceramic material.
The material is fabricated or mixed and then processed in the apparatus of the type described, for example, to form a turbine blade, rotor blade or gear. The formed components are then heated in an oven to remove their organic phase. Test materials did not crack or warp after such treatment indicating that the binder is uniformly removed from the parts during the heating operation. The parts also have been sintered without any pressure to density the material and observations are that at least 80% of these sintered parts make distortion-free ceramic prototype elements. The density of such sintered materials is greater than 95% of its theoretical density. The sintered part also exhibits high strength.
Following is a specific example of the formulation of the feedstock composition and the protocol or procedure make such a feedstock:
EXAMPLE ONE
A silicon nitride powder is first ball milled in a hexane solvent to disperse, deagglomerate and uniformly mix with other ceramic powders, specifically yttrium oxide and aluminum oxide. Other solvents (e.g. ethanol, isopropanol) may be used. The composition of the mixture is as follows:
49.1 wt. % (H.C. Starck M11) Silicon Nitride
5.12 wt. % Yttrium Oxide (Molycorp Inc.)
1.68 wt. % Aluminum Oxide (Ceralox Corp.)
43.2 wt. % Hexane (A.C.S. Reagent or HPLC Grade)
0.9 wt. % Ethomeen C-12 Dispersant
(Akzo Nobel Chemicals, Inc. fatty aminoalcohol)
Subsequent to the mixing of the composition, the hexane is stripped from the mixture by a distillation process. The ceramic powders remain after the stripping operation. The ceramic powders are then batched with the other materials comprising the feedstock composition in a Brabender High Torque mixer to formulate the green ceramic feedstock composition. Following is a summary of the mix in the green feedstock composition:
82.5 wt. % ceramic powder
11.7 wt. % polyethylene-co-ethylacrylate binder
(Union Carbide Corp. DPDA 6182)
3.45 wt. % BASF AL3 Microcrystalline Polyethylene Wax
2.35 wt. % Butyl oleate Plasticizer (Witco Corp. Kemester 4000)
Following the mixing of the material and to create the green ceramic feedstock, the materials are fed as a filament into a machine of the type disclosed in U.S. Pat. No. 5,340,433 and U.S. Pat. No. 5,121,329 or U.S. application Ser. No. 08/825,893. The extruded materials thus define a complex shaped prototype element in accord with the teachings herein. The element is then debindered to eliminate the organic phase. Thereafter, the parts are sintered in an inert nitrogen atmosphere. The observed parts were described above.
EXAMPLE TWO
The same formulation procedure was followed as in Example 1 but with different components as set forth below:
80.8 wt. % Si 3 N 4 (milled in hexane with Al 2 O 3 and Y 2 O 3 sintering aids → same ratio as in Ex. 1.)
11.6 wt. % polyethylene-co-ethylacrylate copolymer
2.8 wt. % BASF AL3 Microcrystalline Polyethylene Wax
3.0 wt. % Beeswax (N.F. Refined)
1.8 wt. % Butyl oleate
EXAMPLE THREE
Again, the same formulation procedure as in Example One was followed:
80.7 wt. % Si 3 N 4 milled powder (w/Al 2 O 3 and Y 2 O 3 as in Ex. 1.)
11.6 wt. % polyethylene-co-ethylacrylate copolymer
5.9 wt. % Beeswax (N.F. Refined)
1.8 wt. % Butyl oleate
EXAMPLE FOUR
A pre-mixed stainless steel powder is batched with the other materials comprising the feedstock composition using a Brabender High Torque mixer to formulate the green ceramic feedstock composition. The following is a summary of the mix in the green feedstock composition:
92.69 wt. % ANVAL 17-4 PH Stainless Steel Powder
4.89 wt. % polyethylene-co-ethylacrylate copolymer
1.46 wt. % BASF AL3 Microcrystalline Polyethylene Wax
0.95 wt. % Butyl oleate Plasticizer (WitcoCorp.Kemester 4000)
The materials were, following binder removal and sintering, successfully formed as prototype elements using the described techniques.
Various other formulations and combinations of the particular elements set forth are possible. Thus the invention is to be limited only by the following claims and equivalent thereof | A ceramic or metal feedstock composition useful for manufacture of prototype elements using a filament or ribbon deposition apparatus, includes a ceramic or metal powder, a binder of ethylene/acrylate copolymer or homopolymer, a wax and liquid plasticizer mixed together in the form of a ribbon or rod which may then be used in a prototyping device. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to recombinant fusion proteins, to growth hormone (GH), to serum albumin and to production of proteins in yeast.
BACKGROUND AND PRIOR ART
[0002] Human serum albumin (HSA), a protein of 585 amino acids, is responsible for a significant proportion of the osmotic pressure of serum and also functions as a carrier of endogenous and exogenous ligands. At present, HSA for clinical use is produced by extraction from human blood. The production of recombinant HA (rHA) in microorganisms has been disclosed in EP 330 451 and EP 361 991.
[0003] The role of albumin as a carrier molecule and its inert nature are desirable properties for use as a stabiliser and transporter of polypeptides. The use of albumin as a component of a fusion protein for stabilising other proteins has been disclosed in WO 93/15199, WO 93/15200, and EP 413 622. The use of N-terminal fragments of HSA for fusions to polypeptides has also been disclosed (EP 399 666). Fusion to the said polypeptide is achieved by genetic manipulation, such that the DNA coding for HSA, or a fragment thereof, is joined to the DNA coding for the said polypeptide. A suitable host is then transformed or transfected with the fused nucleotide sequences, so arranged on a suitable plasmid as to express a fusion polypeptide. Nomura et al (1995) attempted to express human apolipoprotein E in S. cerevistae as a fusion protein with HSA or fragments of HSA, using the HSA pre-sequence to direct secretion. Whilst fusion to full length HSA resulted in the secretion of low levels of the protein into the medium (maximum yield of 6.3 mg per liter), fusion to HSA (1-198) or HSA (1-390) did not result in secretion into the medium.
[0004] Human growth hormone (reviewed by Strobl and Thomas, 1994) consists of a single polypeptide of 191 amino acids, internally cross-linked by two disulphide bonds. Two molecules of hGH receptor bind each molecule of hGH to facilitate signal transduction (Cunningham et al, 1991; de Vos et al, 1992). The C-terminus of the hGH molecule is involved in binding to the first receptor molecule, but the extent to which the N-terminus is involved in receptor binding is not known. The hormone is secreted from the anterior pituitary gland under hypothalamic control, and is responsible for a wide range of growth-promoting effects in the body. Clinically, hGH is used in the treatment of hypopituitary dwarfism, chronic renal insufficiency in childhood, bone fractures and burns. Current methods of production of hGH for therapeutic use are by extraction from human pituitary gland, recombinant expression in Escherichia coli as disclosed in EP 127 305 (Genentech) or recombinant expression in mammalian cell culture (Zeisel et al, 1992).
[0005] In addition, hGH has been expressed intracellularly in yeast (Tokunaga et at, 1985) and this organism may provide an alternative means of production as disclosed in EP 60 057 (Genentech). Tsiomenko et al (1994) reported the role of the yeast MFα-1 prepro leader sequence in the secretion of hGH from yeast. Attachment of the pre-portion of the leader sequence to the hGH gene resulted in hGH accumulation in the periplasm and vacuoles, whilst attachment of the pro-portion to hGH resulted in expression of a non-glycosylated precursor localised inside the cell. Only when both portions of the leader sequence were attached to the hGH gene was hGH secreted into the culture medium. Other secretion signals (pre-sequences) were also ineffective unless a yeast-derived pro sequence was used, suggesting that such a pro sequence was used is critical to the efficient secretion of hGH in yeast.
[0006] In humans, hGH is secreted into the blood in pulses, and in the circulation has a half-life of less than 20 minutes (Haffner et al, 1994). Elimination of the hormone is primarily via metabolism in the liver and kidneys and is more rapid in adults than in children (Kearns et al, 1991). Treatment for hGH deficiency generally lasts for 6 to 24 months, during which hGH is administered either three times a week intramuscularly or on a daily basis subcutaneously. Such a regimen of frequent administration is necessary because of the short half-life of the molecule.
[0007] Poznansky et al (1988) increased the half-life of porcine growth hormone by conjugation with either porcine or human serum albumin (HSA) to form relatively large conjugates of about 180 kD. Chemical reaction using the cross-linking reagent glutaraldehyde resulted in, on average, two molecules of albumin complexed with six molecules of growth hormone. The resulting 180 kD conjugate was found to have an extended half-life in the circulation of rats of 2 to 3 hours, compared to 5 minutes for unconjugated growth hormone. Activity assays showed that the conjugate retained full, and possibly increased activity in vitro, but was inactive in vivo.
SUMMARY OF THE INVENTION
[0008] The invention relates to proteins formed by the fusion of a molecule of albumin, or variants or fragments thereof, to a molecule of growth hormone or variants or fragments thereof, the fusion proteins having an increased circulatory half-life over unfused growth hormone. For convenience, we shall refer to human albumin (HA) and human growth hormone (hGH), but the albumin and growth hormones of other vertebrates are included also. Preferably, the fusion protein comprises HA, or a variant or fragment thereof, as the N-terminal portion, with hGH or a variant or fragment thereof as the C-terminal portion, so as to minimise any possible negative effects on receptor binding. Alternatively, a fusion protein comprising HA, or a variant or fragment thereof, as the C-terminal portion, with hGH or a variant or fragment thereof as the N-terminal portion, may also be capable of signal transduction. Generally, the polypeptide has only one HA-derived region and one GH-derived region.
[0009] Additionally, the fusion proteins of the invention may include a linker peptide between the two fused portions to provide a greater physical separation between the two moieties and thus maximise the availability of the hGH portion to bind the hGH receptor. The linker peptide may consist of amino acids such that it is flexible or more rigid.
[0010] The linker sequence may be cleavable by a protease or chemically to yield the growth hormone related moiety. Preferably, the protease is one which is produced naturally by the host, for example the S. cerevisiae protease kex2 or equivalent proteases. Hence, a further aspect of the invention provides a process for preparing growth hormone or a variant or fragment thereof by expressing a polynucleotide which encodes a polypeptide of the invention in a suitable host, cleaving the cleavable linker to yield the GH-type compound and recovering the GH-type compound from the host culture in a more pure form.
[0011] We have discovered that the polypeptides of the invention are significantly more stable in solution than hGH. The latter rapidly becomes inactive when stored in solution at 4° C. for over one month. Currently marketed hGH is sold as a freeze-dried powder.
[0012] Suitably, the fusion polypeptides are produced as recombinant molecules by secretion from yeast, a microorganism such as a bacterium, human cell line or a yeast. Preferably, the polypeptide is secreted from the host. We have found that, by fusing the hGH coding sequence to the HA coding sequence, either to the 5′ end or 3′ end, it is possible to secrete the fusion protein from yeast without the requirement for a yeast-derived pro sequence. This was surprising, as other workers have found that a yeast derived pro sequence was needed for efficient secretion of hGH in yeast. For example, Hiramitsu et al (1990, 1991) found that the N-terminal portion of the pro sequence in the Mucor pusillus rennin pre-pro leader was important. Other authors, using the MFα-1 signal, have always included the MFα-1 pro sequence when secreting hGH. The pro sequences were believed to assist in the folding of the hGH by acting as an intramolecular chaperone. The present invention shows that HA or fragments of HA can perform a similar function.
[0013] Hence, a particular embodiment of the invention comprises a DNA construct encoding a signal sequence effective for directing secretion in yeast, particularly a yeast-derived signal sequence (especially one which is homologous to the yeast host), and the fused molecule of the first aspect of the invention, there being no yeast-derived pro sequence between the signal and the mature polypeptide.
[0014] The Saccharomyces cerevisiae invertase signal is a preferred example of a yeast-derived signal.
[0015] Conjugates of the kind prepared by Poznansky et al (1988). in which separately-prepared polypeptides are joined by chemical cross-inking, are not contemplated
[0016] The albumin or hGH may be a variant of normal HSA/rHA (termed hereinafter “HA”) or hGH, respectively. By “variants” we include insertions, deletions and substitutions, either conservative or non-conservative, where such changes do not substantially alter one or more of the oncotic, useful ligand-binding and non-immunogenic properties of albumin or, in the case of hGH, its non-immunogenicity and ability to bind and activate the hGH receptor. In particular, we include naturally-occurring polymorphic variants of human albumin and fragments of human albumin, for example those fragments disclosed in EP 322 094 (namely HA (1-n), where n is 369 to 419). The albumin or growth hormone may be from any vertebrate, especially any mammal, for example human, cow, sheep, pig, hen or salmon. The albumin and GH parts of the fusion may be from differing animals.
[0017] By “conservative substitutions” is intended swaps within groups such as Gly, Ala; Val, Ile, Leu; Asp, Glu; Asn, Gln; Ser, Thr; Lys, Arg; and Phe, Tyr. The variant will usually have at least 75% (preferably at least 80%, 90%, 95% or 99%) sequence identity with a length of normal HA or hGH which is the same length as the variant and which is more identical thereto than any other length of normal HA or hGH, once the allowance is made for deletions and insertions as is customary in this art. Generally speaking, an HA variant will be at least 100 amino acids long, preferably at least 150 amino acids long. The HA variant may consist of or comprise at least one whole domain of HA, for example domains 1 (1-194), 2 (195-387), 3 (388-585), 1+2 (1-387), 2+3 (195-585) or 1+3 (1-194, +388-585). Each domain is itself made up of two homologous subdomains namely 1-105 120-194, 195-291, 316-387, 388-491 and 512-585, with flexible inter-subdomain linker regions comprising residues Lys106 to Glu199, Glu292 to Val315 and Glu492 to Ala511. Preferably, the HA part of the fusion comprises at least one subdomain or domain of HA or conservative modifications thereof. If the fusion is based on subdomains, some or all of the adjacent linker is preferably used to link to the hGH moiety. The hGH variant should have GH activity, and will generally have at least 10 amino acids, (although some authors have found activity with only 4 residues), preferably at least 20, preferably at least 50, 100, 150, 180 or 191, amino acids long, and preferably retains its cysteines for both internal disulphide bonds.
[0018] The fused molecules of the invention generally have a molecular weight of less than 100 kD, for example less than 90 kD or 70 kD. They are therefore much smaller than the 180 kD conjugates of Poznansky et al (referred to above), which were inactive in vivo. They will normally have a molecular weight of at least 20 kD, usually at least 30 kD or 50 kD. Most fall within the molecular weight range 60-90 kD.
[0019] A second main aspect of the invention provides a yeast transformed to express a fusion protein of the invention.
[0020] In addition to the transformed host cells themselves, the present invention also contemplates a culture of those cells, preferably a monoclonal (clonally homogeneous) culture, or a culture derived from a monoclonal culture, in a nutrient medium. Especially if the polypeptide is secreted, the medium will thus contain the polypeptide, with the cells, or without the cells if they have been filtered or centrifuged away
[0021] Many expression systems are known, including bacteria (for example E. coli and Bacillus subtilis ), yeasts (for example Saccharomyces cerevisiae, Kluyveronmyces lactis and Pichia pastoris , filamentous fungi (for example Aspergillus), plant cells, animal cells and insect cells.
[0022] The desired protein is produced in conventional ways, for example from a coding sequence inserted in the host chromosome or on a free plasmid.
[0023] The yeasts are transformed with a coding sequence for the desired protein in any of the usual ways, for example electroporation. Methods for transformation of yeast by electroporation are disclosed in Becker & Guarente (1990) Methods Enzymol. 194, 182.
[0024] Successfully transformed cells, ie cells that contain a DNA construct of the present invention, can be identified by well known techniques. For example, cells resulting from the introduction of an expression construct can be grown to produce the desired polypeptide. Cells can be harvested and lysed and their DNA content examined for the presence of the DNA using a method such as that described by Southern (1975) J. Mol. Biol. 98, 503 or Berent et al (1985) Biotech. 3, 208. Alternatively, the presence of the protein in the supernatant can be detected using antibodies.
[0025] Useful yeast plasmid vectors include pRS403-406 and pRS413-416 and are generally available from Stratagene Cloning Systems, La Jolla, Calif. 92037, USA. Plasmids pRS403, pRS404, pRS405 and pRS406 are Yeast Integrating plasmids (YIps) and incorporate the yeast selectable markers HIS3, TRP1, LEU2 and URA3. Plasmids pRS413-416 are Yeast Centromere plasmids (YCps).
[0026] A variety of methods have been developed to operably link DNA to vectors via complementary cohesive termini For instance, complementary homopolymer tracts can be added to the DNA segment to be inserted to the vector DNA. The vector and DNA segment are then joined by hydrogen bonding between the complementary homopolymeric tails to form recombinant DNA molecules.
[0027] Synthetic linkers containing one or more restriction sites provide an alternative method of joining the DNA segment to vectors. The DNA segment, generated by endonuclease restriction digestion, is treated with bacteriophage T4 DNA polymerase or E. coli DNA polymerase I, enzymes that remove protruding, 3′-single-stranded termini with their 3′-5′-exonucleolytic activities, and fill in recessed 3′-ends with their polymerizing activities.
[0028] The combination of these activities therefore generates blunt-ended DNA segments. The blunt-ended segments are then incubated with a large molar excess of linker molecules in the presence of an enzyme that is able to catalyze the ligation of blunt-ended DNA molecules, such as bacteriophage T4 DNA ligase. Thus, the products of the reaction are DNA segments carrying polymeric linker sequences at their ends. These DNA segments are then cleaved with the appropriate restriction enzyme and ligated to an expression vector that has been cleaved with an enzyme that produces termini compatible with those of the DNA segment.
[0029] Synthetic linkers containing a variety of restriction endonuclease sites are commercially available from a number of sources including International Biotechnologies Inc, New Haven, Conn., USA.
[0030] A desirable way to modify the DNA in accordance with the invention, if, for example, HA variants are to be prepared, is to use the polymerase chain reaction as disclosed by Saiki et al (1988) Science 239, 487-491. In this method the DNA to be enzymatically amplified is flanked by two specific oligonucleotide primers which themselves become incorporated into the amplified DNA. The said specific primers may contain restriction endonuclease recognition sites which can be used for cloning into expression vectors using methods known in the art.
[0031] Exemplary genera of yeast contemplated to be useful in the practice of the present invention as hosts for expressing the fusion proteins are Pichia (Hansenula), Saccharomyces, Kluyveromyces, Candida, Torulopsis, Torulaspora, Schizosaccharomyces, Citeromyces, Pachysolen, Debaromyces, Metschunikowia, Rhodosporidium, Leucosporidium, Botryoascus, Sporidiobolus, Endomycopsis, and the like. Preferred genera are those selected from the group consisting of Saccharomyces, Schizosaccharomyces, Kluyveromyces, Pichia and Torulaspora. Examples of Saccharomyces spp. are S. cerevisiae, S. italicus and S. rouxii . Examples of Kluyveromyces spp are K. fragilis, K. lactis and K. marxianus . A suitable Torulaspora species is T. delbrueckii . Examples of Pichia (Hansenula) spp. are P. angusta (formerly H. polymorpha ), P. anomala (formerly H. anomala ) and P. pastoris.
[0032] Methods for the transformation of S. cerevisiae are taught generally in EP 251 744, EP 258 067 and WO 90/01063, all of which are incorporated herein by reference.
[0033] Suitable promoters for S. cerevisiae include those associated with the PGK1 gene, GAL1 or GAL10 genes, CYC1, PHO5, TRP1, ADH1, ADH2, the genes for glyceraldehyde-3-phosphate dehydrogenase, hexokinase, pyruvate decarboxylase, phosphofructokinase, triose phosphate isomerase, phosphoglucose isomerase, glucokinase, α-mating factor pheromone, a-mating factor pheromone, the PRB1 promoter the GUT2 promoter, the GPD1 promoter and hybrid promoters involving hybrids of parts of 5′ regulatory regions with parts of 5′ regulatory regions of other promoters or with upstream activation sites (eg the promoter of EP-A-258 067).
[0034] Convenient regulatable promoters for use in Schizosaccharomyces pombe are the thiamine-repressible promoter from the nmt gene as described by Maundrell (1990) J. Biol. Chem. 265, 10857-10864 and the glucose-repressible fbp1 gene promoter as described by Hoffman & Winston (1990) Genetics 124, 807-816.
[0035] Methods of transforming Pichia for expression of foreign genes are taught in, for example, Cregg et al (1993), and various Phillips patents (eg U.S. Pat. No. 4,857,467, incorporated herein by reference), and Pichia expression kits are commercially available from Invitrogen BV, Leek, Netherlands, and Invitrogen Corp., San Diego, Calif. Suitable promoters include AOX1 and AOX2.
[0036] Gleeson et al (1986) J. Gen. Microbiol. 132, 3459-3465 include information on Hansenula vectors and transformation, suitable promoters being MOX1 and FMD1; whilst EP 361 991, Fleer et al (1991) and other publications from Rhône-Poulenc Rorer teach how to express foreign proteins in Kluyveromyces spp., a suitable promoter being PGK1.
[0037] The transcription termination signal is preferably the 3′ flanking sequence of a eukaryotic gene which contains proper signals for transcription termination and polyadenylation. Suitable 3′ flanking sequences may, for example, be those of the gene naturally linked to the expression control sequence used, ie may correspond to the promoter. Alternatively, they may be different in which case the termination signal of the S. cerevisiae ADH1 gene is preferred.
[0038] The desired fusion protein may be initially expressed with a secretion leader sequence, which may be any leader effective in the yeast chosen. Leaders useful in S. cerevisiae include that from the mating factor α polypeptide (MFα-1) and the hybrid leaders of EP-A-387 319. Such leaders (or signals) are cleaved by the yeast before the mature albumin is released into the surrounding medium. Further such leaders include those of S. cerevisiae invertase (SUC2) disclosed in JP 62-096086 (granted as 91/036516), acid phosphatase (PH05), the pre-sequence of MFα-1,β-glucanase (BGL2) and killer toxin; S. diastaticus glucoamylase II; S. carlsbergensis α-galactosidase (MEL1); K. lactis killer toxin; and Candida glucoamylase.
[0039] The fusion protein of the invention or a formulation thereof may be administered by any conventional method including parenteral (eg subcutaneous or intramuscular) injection or intravenous infusion. The treatment may consist of a single dose or a plurality of doses over a period of time.
[0040] Whilst it is possible for a fusion protein of the invention to be administered alone, it is preferable to present it as a pharmaceutical formulation, together with one or more acceptable carriers. The carrier(s) must be “acceptable” in the sense of being compatible with the fusion protein and not deleterious to the recipients thereof. Typically, the carriers will be water or saline which will be sterile and pyrogen free. The formulation should be non-immunogenic; vaccine-type formulations involving adjuvants are not contemplated.
[0041] The formulations may conveniently be presented in unit dosage form and may be prepared by any of the methods well known in the art of pharmacy. Such methods include the step of bringing into association the fusion protein with the carrier which constitutes one or more accessory ingredients. In general the formulations are prepared by uniformly and intimately bringing into association the active ingredient with liquid carriers or finely divided solid carriers or both, and then, if necessary, shaping the product
[0042] Formulations suitable for parenteral administration include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents. The formulations may be presented in unit-dose or multi-dose containers, for example seated ampoules and vials, and may be stored in a freeze-dried (lyophilised) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders.
[0043] Preferred unit dosage formulations are those containing a daily dose or unit, daily sub-dose or an appropriate fraction thereof, of an active ingredient.
[0044] The fusion proteins of the invention may be used in the treatment of any condition in which growth hormone is indicated, for example isolated growth hormone deficiency, panhypopituitarism, following cranial irradiation (eg in the treatment of leukaemia or brain tumours), Turner's syndrome, Down's syndrome, intrauterine growth retardation, idiopathic growth deficiency, chronic renal failure, achondroplasia, female infertility and various catabolic disorders. They may also be used in the stimulation of growth, and/or enhancement of lean meat proportion, in farm animals such as cows, sheep, goats and pigs.
[0045] The fusion protein may be administered together with insulin-like growth factor I (IGF-I).
[0046] The dosage can be calculated on the basis of the potency of the fusion protein relative to the potency of hGH, whilst taking into account the prolonged serum half-life of the fusion proteins compared to that of native hGH. Growth hormone is typically administered at 0.3 to 30.0 IU/kg/week, for example 0.9 to 12.0 IU/kg/week, given in three or seven divided doses for a year or more. In a fusion protein consisting of full length HA fused to full length GH, an equivalent dose in terms of units would represent a greater weight of agent but the dosage frequency can be reduced, for example to twice a week, once a week or less.
[0047] Preferred examples of the invention will now be described by way of example and with reference to the accompanying figures, in which:
[0048] [0048]FIG. 1 shows the human growth hormone cDNA sequence, encoding mature hGH;
[0049] [0049]FIG. 2 shows a restriction enzyme map of pHGH1;
[0050] [0050]FIG. 3 shows a restriction enzyme map of pBST(+) and the DNA sequence of the polylinker;
[0051] [0051]FIG. 4 shows the construction of pHGH12,
[0052] [0052]FIG. 5 shows the construction of pHGH16;
[0053] [0053]FIG. 6 shows the HSA cDNA sequence, more particularly the region encoding the mature protein;
[0054] [0054]FIG. 7 shows the construction of pHGH14;
[0055] [0055]FIG. 8 shows the construction of pHGH38;
[0056] [0056]FIG. 9 shows the construction of pHGH31;
[0057] [0057]FIG. 10 shows the construction of pHGH58 or pHGH59 (Example 7);
[0058] [0058]FIG. 11 is a scheme for constructing fusions having spacers (Example 7); and
[0059] [0059]FIG. 12 shows the results of a pharmacokinetic study showing the clearance of 125 I-labelled rHA-hGH compared to that of hGH following iv injection in rats. Data are from two rats in each group, and include total radioactivity and radioactivity which could be precipitated by TCA, ie that associated with protein rather than as free 125 I. The calculated clearance half-life for hGH was approximately 6 minutes, compared to approximately 60 minutes for the rHA-hGH fusion protein. See Example 3.
[0060] —hGH (total counts)
[0061] ▪—hGH (TCA precipitated counts)
[0062] ▾—rHA-hGH (total counts)
[0063] ▴—rHA-hGH (TCA precipitated counts).
DETAILED DESCRIPTION OF THE INVENTION
[0064] All standard recombinant DNA procedures are as described in Sambrook et al (1989) unless otherwise stated. The DNA sequences encoding HSA were derived from the cDNA disclosed in EP 201 239.
EXAMPLE 1
Cloning of the hGH cDNA
[0065] The hGH cDNA was obtained from a human pituitary gland cDNA library (catalogue number HL1097v, Clontech Laboratories, Inc) by PCR amplification. Two oligonucleotides suitable for PCR amplification of the hGH cDNA, HGH1 and HGH2, were synthesised using an Applied Biosystems 380B Oligonucleotide Synthesiser.
HGH1: 5′-CCCAAGAATTCCCTTATCCAGGC-3′ HGH2: 5′-GGGAAGCTTAGAAGCCACAGGATCCCTCCACAG-3′
[0066] HGH1 and HGH2 differed from the equivalent portion of the hGH cDNA sequence (FIG. 1, Martial et al, 1979) by two and three nucleotides, respectively, such that after PCR amplification an EcoRI site would be introduced to the 5′ end of the cDNA and a BamHI site would be introduced into the 3′ end of the cDNA. In addition, HGH2 contained a HindIII site immediately downstream of the hGH sequence.
[0067] PCR amplification using a Perkin-Elmer-Cetus Thermal Cycler 9600 and a Perkin-Elmer-Cetus PCR kit, was performed using single-stranded DNA template isolated from the phage particles of the cDNA library as follows: 10 μL phage particles were lysed by the addition of 10 μL phage lysis buffer (280 μg/mL proteinase K in TE buffer) and incubation at 55° C. for 15 min followed by 85° C. for 15 min After a 1 min incubation on ice, phage debris was pelleted by centriftigation at 14,000 rpm for 3 min. The PCR mixture contained 6 μL of this DNA template, 0.1 μM of each primer and 200 μM of each deoxyribonucleotide. PCR was carried out for 30 cycles, denaturing at 94° C. for 30 s, annealing at 65° C. for 30 s and extending at 72° C. for 30 s, increasing the extension time by 1 s per cycle. Analysis of the reaction by gel electrophoresis showed a single product of the expected size (589 base pairs).
[0068] The PCR product was purified using Wizard PCR Preps DNA Purification System (Promega Corp) and then digested with EcoRI and HindIII. After further purification of the EcoRI-HindIII fragment by gel electrophoresis, the product was cloned into pUC19 (GIBCO BRL) digested with EcoRI and HindIII, to give pHGH1 (FIG. 2). DNA sequencing of the EcoRI-HindIII region showed that the PCR product was identical in sequence to the hGH sequence (Martial et al, 1979), except at the 5′ and 3′ ends, where the EcoRI and BamHI sites had been introduced, respectively.
EXAMPLE 2
Expression of the hGH cDNA
[0069] The polylinker sequence of the phagemid pBluescribe (+) (Stratagene) was replaced by inserting an oligonucleotide linker, formed by annealing two 75-mer oligonucleotides, between the EcoRI and HindIII sites to form pBST(+) (FIG. 3). The new polylinker included a unique NotI site (the full sequence in the region of the polylinker is given in FIG. 3).
[0070] The NotI HSA expression cassette of pAYE309 (EP 431 880) comprising the PRB1 promoter. DNA encoding the HSA/MFα-1 hybrid leader sequence, DNA encoding HSA and the ADH1 terminator, was transferred to pBST(+) to form pHA1 (FIG. 4). The HSA coding sequence was removed from this plasmid by digestion with HindIII followed by religation to form pHA2 (FIG. 4).
[0071] Cloning of the hGH cDNA, as described in Example 1, provided the hGH coding region lacking the pro-hGH sequence and the first 8 base pairs (bp) of the mature hGH sequence. In order to construct an expression plasmid for secretion of hGH from yeast, a yeast promoter, signal peptide and the first 8 bp of the hGH sequence were attached to the 5′ end of the cloned hGH sequence as follows:
[0072] The HindIII-SfaNI fragment from pHA1 was attached to the 5′ end of the EcoRI-HindIII fragment from pHGH1 via two synthetic oligonucleotides, HGH3 and HGH4:
HGH3: 5′-GATAAAGATTCCCAAC-3′ HGH4: 5′-AATTGTTGGGAATCTTT-3′
[0073] The HindIII fragment so formed was cloned into HindIII-digested pHA2 to make pHGH2 (FIG. 4), such that the hGH cDNA was positioned downstream of the PRB1 promoter and HSA/MFα-1 fusion leader sequence (WO 90/01063). The NotI expression cassette contained in pHGH2, which included the ADH1 terminator downstream of the hGH cDNA, was cloned into NotI-digested pSAC35 (Sleep et al, 1990) to make pHGH12 (FIG. 4). This plasmid comprised the entire 2 μm plasmid to provide replication functions and the LEU2 gene for selection of transformants.
[0074] pHGH12 was introduced into S. cerevisiae DB1 (Sleep et al, 1990) by transformation and individual transformants were grown for 3 days at 30° C. in 10 mL YEPD (1% w/v yeast extract, 2% w/v peptone, 2% w/v dextrose). After centrifugation of the cells, the supernatants were examined by SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and were found to contain protein which was of the expected size and which was recognised by anti-hGH antiserum (Sigma, Poole, UK) on Western blots.
EXAMPLE 3
Cloning and Expression of an HSA-hGH Fusion Protein
[0075] In order to fuse the HSA cDNA to the 5′ end of the hGH cDNA, the pHA1 HindIII-Bsu36I fragment (containing most of the HSA cDNA) was joined to the pHGH1 EcoRI-HindIII fragment (containing most of the hGH cDNA) via two oligonucleotides, HGH7 and HGH8:
HGH7: 5′-TTAGGCTTATTCCCAAC-3′ HGH8: 5′-AATTGTTGGGAATAAGCC-3′
[0076] The HindIII fragment so formed was cloned into pHA2 digested with HindIII to make pHGH10 (FIG. 5), and the NotI expression cassette of this plasmid was cloned into NotI-digested pSAC35 to make pHGH16 (FIG. 5).
[0077] pHGH16 was used to transform S. cerevisiae DB1 and supernatants of cultures were analysed as in Example 2. A predominant band was observed that had a molecular weight of approximately 88 kD, corresponding to the combined masses of HA and hGH. Western blotting using anti-HSA and anti-hGH antisera (Sigma) confirmed the presence of the two constituent parts of the fusion protein.
[0078] The fusion protein was purified from culture supernatant by cation exchange chromatography, followed by anion exchange and gel permeation chromatography. Analysis of the N-terminus of the protein by amino acid sequencing confirmed the presence of the expected albumin sequence.
[0079] An in vitro growth hormone activity assay (Ealey et al, 1995) indicated that the fusion protein possessed full hGH activity, but that the potency was reduced compared to the hGH standard. In a hypophysectomised rat weight gain model, performed essentially as descried in the European Pharmacopoeia (1987, monograph 556), the fusion molecule was more potent than hGH when the same number of units of activity (based on the above in vitro assay) were administered daily. Further experiments in which the fusion protein was administered once every four days showed a similar overall growth response to a daily administration of hGH. Pharmacokinetic experiments in which 125 I-labelled protein was administered to rats indicated an approximately ten-fold increase in circulatory half life for the fusion protein compared to hGH (FIG. 12).
[0080] A similar plasmid was constructed in which DNA encoding the S. cerevisiae invertase (SUC2) leader sequence replaced the sequence for the hybrid leader, such that the encoded leader and the junction with the HSA sequence were as follows:
MLLQAFLFLLAGFAAKISA↓DARKS. . . Invertase leader HSA
[0081] On introduction into S. cerevisiae DB1, this plasmid directed the expression and secretion of the fusion protein at a level similar to that obtained with pHGH16. Analysis of the N-terminus of the fusion protein indicated precise and efficient cleavage of the leader sequence from the mature protein.
EXAMPLE 4
Cloning and Expression of an hGH-HSA Fusion Protein
[0082] In order to fuse the hGH cDNA to the 5′ end of the HSA cDNA (FIG. 6), the HSA cDNA was first altered by site-directed mutagenesis to introduce an EcoNI site near the 5′ end of the coding region. This was done by the method of Kunkel et al (1987) using single-stranded DNA template prepared from pHA1 and a synthetic oligonucleotide, LEU4:
[0083] LEU4: 5′-GAGATGCACACCTGAGTGAGG-3′
[0084] Site-directed mutagenesis using this oligonucleotide changed the coding sequence of the HSA cDNA from Lys4 to Leu4 (K4L). However, this change was repaired when the hGH cDNA was subsequently joined at the 5′ end by linking the pHGH2 NotI-BamHI fragment to the EcoNI-NotI fragment of the mutated pHA1, via the two oligonucleotides HGH5 and HGH6:
HGH5: 5′-GATCCTGTGGCTTCGATGCACACAAGA-3′ HGH6: 5′-CTCTTGTGTGCATCGAAGCCACAG-3′
[0085] The NotI fragment so formed was cloned into NotI-digested pSAC35 to make pHGH14 (FIG. 7). pHGH14 was used to transform S. cerevisiae DB1 and supernatants of cultures were analysed as in Example 2. A predominant band was observed that had a molecular weight of approximately 88 kD, corresponding to the combined masses of hGH and HA. Western blotting using anti-HSA and anti-hGH antisera confirmed the presence of the two constituent parts of the fusion protein.
[0086] The fusion protein was purified from culture supernatant by cation exchange chromatography, followed by anion exchange and gel permeation chromatography. Analysis of the N-terminus of the protein by amino acid sequencing confirmed the presence of the expected hGH sequence.
[0087] In vitro studies showed that the fusion protein retained hGH activity, but was significantly less potent than a fusion protein comprising full-length HA (1-585) as the N-terminal portion and hGH as the C-terminal portion, as described in Example 3.
EXAMPLE 5
Construction of Plasmids for the Expression of hGH Fusions to Domains of HSA
[0088] Fusion polypeptides were made in which the hGH molecule was fused to the first two domains of HA (residues 1 to 387). Fusion to the N-terminus of hGH was achieved by joining the pHA1 HindIII-SapI fragment, which contained most of the coding sequence for domains 1 and 2 of HA, to the pHGH1 EcoRI-HindIII fragment, via the oligonucleotides HGH11 and HGH12:
HGH11: 5′-TGTGGAAGAGCCTCAGAATTTATTCCCAAC-3′ HGH12: 5′-AATTGTTGGGAATAAATTCTGAGGCTCTTCC-3′
[0089] The HindIII fragment so formed was cloned into HindIII-digested pHA2 to make pHGH37 (FIG. 8) and the NotI expression cassette of this plasmid was cloned into NotI-digested pSAC35. The resulting plasmid, pHGH38 (FIG. 8), contained an expression cassette that was found to direct secretion of the fusion polypeptide into the supernatant when transformed into S. cerevisiae DB1. Western blotting using anti-HSA and anti-hGH antisera confirmed the presence of the two constituent parts of the fusion protein.
[0090] The fusion protein was purified from culture supernatant by cation exchange chromatography followed by gel permeation chromatography. In vivo studies with purified protein indicated that the circulatory half-life was longer than that of hGH, and similar to that of a fusion protein comprising full-length HA (1-585) as the N-terminal portion and hGH as the C-terminal portion, as described in Example 3. In vitro studies showed that the fusion protein retained hGH activity.
[0091] Using a similar strategy as detailed above, a fusion protein comprising the first domain of HA (residues 1-194) as the N-terminal portion and hGH as the C-terminal portion, was cloned and expressed in S. cerevisiae DB1. Western blotting of culture supernatant using anti-HSA and anti-hGH antisera confirmed'the presence of the two constituent parts of the fusion protein.
EXAMPLE 6
Expression of hGH by Introducing a Cleavage Site Between HSA and hGH
[0092] Introduction of a peptide sequence that is recognised by the Kex2 protease, between the HA-hGH fusion protein, allows secretion of hGH. A sequence encoding Ser Leu Asp Lys Arg was introduced using two oligonucleotides, HGH14 and HGH15:
HGH14: 5′-TT A GGCTTAAGC TT GG ATAAAAGAT TCCCAAC-3′ HGH15: 5′- AATTGTT GGG AATCTTTTAT C CAA GCTTAAGCC-3′
[0093] These were used to join the pHA1 HindIII-Bsu36I fragment to the pHGH1 EcoRI-HindIII fragment, which were then cloned into HindIII-digested pHA2 to make pHGH25 (FIG. 9) The NotI expression cassette of this plasmid was cloned into NotI-digested pSAC35 to make pHGH31 (FIG. 9)
[0094] [0094] S. cerevisiae DBI transformed with pHGH31 was found to secrete two major species, as determined by SDS-PAGE analysis of culture supernatants. The two species had molecular weights of approximately 66 kD, corresponding to (full length) HA, and 22 kD, corresponding to (full length) hGH, indicating in vivo cleavage of the fusion protein by the Kex2 protease, or an equivalent activity. Western blotting using anti-HSA and anti-hGH antisera confirmed the presence of the two separate species. N-terminal sequence analysis of the hGH moiety confirmed the precise and efficient cleavage from the HA moiety.
[0095] The hGH moiety was purified from culture supernatant by anion exchange chromatography followed by gel permeation chromatography. In vitro studies with the purified hGH showed that the protein was active and fully potent.
[0096] Using a similar strategy, fusion proteins comprising either the first domain of HA (residues 1-194) or the first two domains of HA (residues 1-387), followed by a sequence recognised by the Kex2p protease, followed by the hGH cDNA, were cloned and expressed in S. cerevisiae DB1. Western blotting of culture supernatant using anti-HSA and anti-hGH antisera confirmed the presence of the two separate species.
EXAMPLE 7
Fusion of HSA to hGH Using a Flexible Linker Sequence
[0097] Flexible linkers, comprising repeating units of [Gly-Gly-Gly-Gly-Ser] n , where n was either 2 or 3, were introduced between the HSA and hGH fusion protein by cloning of the oligonucleotides HGH16, HGH17, HGH18 and HGH19:
HGH16: 5′-TT A GGC TTAGGTGG CGGTGGATCCGGCGGTGG TGGAT CTTT CCCAAC-3′ HGH17: 5′- AA TTGTTGGG AAAGAT CCACCACCGCCG GAT CCACCGCCAC CTAAGCC-3′ HGH18: 5′-TTAGGCTTAGGCGGTGGTGGATCTGGTGGCGGCGGATCTGG TGGCGGTGGATCCTTCCCAAC-3′ HGH19: 5′- AATT G TTGGGAA GGATCCACCGCC ACCAGAT CCGCCGCCAC CA GATCCACCACCGCCT AAGCC -3′
[0098] Annealing of HGH16 with HGH17 resulted in n=2, while HGH18 annealed to HGH19 resulted in n=3. After annealing, the double-stranded oligonucleotides were cloned with the EcoRI-Bsu36I fragment isolated from pHGH1 into Bsu36I-digested pHGH10 to make pHGH56 (where n=2) and pHGH57 (where n=3) (FIG. 10). The NotI expression cassettes from these plasmids were cloned into NotI-digested pSAC35 to make pHGH58 and pHGH59, respectively.
[0099] Cloning of the oligonucleotides to make pHGH56 and pHGH57 introduced a BamHI site in the linker sequences, as shown in FIG. 11. It was therefore possible to construct linker sequences in which n=1 and n=4, by joining either the HindIII-BamHI fragment from pHGH56 to the BamHI-HindIII fragment from pHGH57 (making n=1), or the HindIII-BamHI fragment from pHGH57 to the BamHI-HindIII fragment from pHGH56 (making n=2). Cloning of these fragments into the HindIII site of pHA2 (described in Example 2), resulted in pHGH60 (n=1) and pHGH61 (n4) (see FIG. 11). The NotI expression cassettes from pHGH60 and pHGH61 were cloned into NotI-digested pSAC35 to make pHGH62 and pHGH63, respectively.
[0100] Transformation of S. cerevisiae with pHGH58. pHGH59, pHGH62 and pHGH63 resulted in transformants that secreted the fusion polypeptides into the supernatant.
[0101] Western blotting using anti-HSA and anti-hGH antisera confirmed the presence of the two constituent parts of the fusion proteins.
[0102] The fusion proteins were purified from culture supernatant by cation exchange chromatography, followed by anion exchange and gel permeation chromatography. Analysis of the N-termini of the proteins by amino acid sequencing confirmed the presence of the expected albumin sequence. Analysis of the purified proteins by electrospray mass spectrometry confirmed an increase in mass of 315 D (n=1), 630 D (n=2), 945 D (n=3) and 1260 D (n=4) compared to the HSA-hGH fusion protein described in Example 3, as expected. The purified protein was found to be active in vitro.
REFERENCES
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[0118] Sambrook, J. et at (1989) Molecular Cloning: a Laboratory Manual, 2nd edition Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY.
[0119] Sleep, D. et at (1990) Bio/Technology 8, 42-46.
[0120] Strobl, J. S. and Thomas, M. J. (1994) Pharmacol. Rev. 46, 1-34.
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[0123] Zeisel, H. J. et at (1992) Horm. Res. 37 (Suppl. 2), 5-13. | Fusion proteins of albumin and growth hormone, or fusions of variants of either, are secreted well in yeast and have increased serum and storage stability. | 2 |
This application claims benefit of Provisional application Ser. No. 60/038,995, Feb. 14, 1997.
BACKGROUND
Over the last thirty years the number of people playing lacrosse has increased dramatically. Today, in some locations, little league lacrosse is as popular as little league baseball, college teams are drawing over 30,000 people to a single game, and a professional league has been formed with teams in many of the largest cities around the United States.
As the sport has grown, the quality of play has also improved. Players are faster, stronger, and more skilled than ever before. Today, it is not uncommon for players to shoot a lacrosse ball in excess of 100 mph or pass behind their back with pin-point accuracy. As a result, the players are demanding more of their equipment. The old hand carved wooden sticks are no longer sufficient.
To satisfy this demand, companies have improved the design of lacrosse sticks. The old wooden sticks have been replaced by the combination of an aluminum or titanium handle and a plastic head. The new handles and heads are designed to decrease the stick's weight, increase its durability, and improve its overall performance. However, no one has designed an apparatus or method for stringing a traditional pocket for a lacrosse stick; let alone stringing a high quality traditional pocket consistently.
People have tried to improve the quality of the pockets by stringing the pockets with different materials or in different patterns, but none of these ideas have succeeded. For example, mesh pockets were created as an alternative to traditional pockets. Although mesh pockets are easier to string, these pockets do not provide the ball control, accurate passing, and fast shooting demanded by today's players. As a result, traditional pockets are still used in over 75% of all lacrosse sticks.
To obtain a quality lacrosse pocket, lacrosse players must buy the materials for a pocket separately from the stick and pay an expert to install the pocket because the pockets sold at retail stores are strung inconsistently (i.e., the nylon placement, tension, depth, and shape of the pocket are random). If a lacrosse player does not know an expert, they must suffer the consequences of using a pocket which provides inadequate ball control, passing accuracy, and shooting speed. In addition, even an expert cannot string the same pocket twice in the same way. Thus, every time a player uses a new pocket, it takes several weeks to become familiar with how that particular pocket passes and shoots. These inconsistent pockets are a significant problem because lacrosse sticks frequently break during the middle of a game.
What is needed is an apparatus and method for stringing a traditional lacrosse pocket consistently.
What is needed is an apparatus and method for stringing a traditional lacrosse pocket without requiring an expert.
What is needed is an apparatus and method for stringing a traditional lacrosse pocket that can be mass produced to satisfy the growing demand.
SUMMARY OF THE INVENTION
The present invention is a new apparatus and method for stringing traditional pockets for a lacrosse stick. The present invention uses a plurality of guides to hold the four thongs typically used in a traditional pocket at any depth desired by the user and guides the user in the nylon placement during stringing. The guides of the present invention can also be customized to produce a variety of different pockets. Thus, the present invention greatly decreases the skill required to install a high quality traditional pocket in a lacrosse stick.
The present invention also increases the consistency in the shape of the pocket. For example, if someone strings a traditional pocket with the present invention, the present invention enables the user to replicate the same pocket because the depth of the thongs and the nylon placement are controlled. In other words, the present invention removes the most influential variables associated with the installation of a traditional lacrosse product.
Consequently, lacrosse players will no longer be forced to become familiar with a different pocket shape every time their stick breaks. With the present invention, lacrosse players can prepare backup sticks with essentially identical pockets, allowing the players to pass and shoot as confidentially with their backup stick as they did with their primary stick.
In addition, the present invention also decreases the amount of time required to string a traditional pocket. By holding the thongs and dictating the nylon placement, the present invention frees the user's hands to weave the nylon.
As a result, lacrosse players will no longer have to buy a stick from a store, tear out the pocket, and pay an expert to string it properly. Using the present invention, any lacrosse player can consistently string high quality pockets. Or, if the present invention is adopted by lacrosse stick manufacturers, lacrosse players will be able to buy a stick strung by a manufacturer and use the stick immediately. The present invention works with any type of lacrosse head.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a head of a lacrosse stick strung with a traditional pocket.
FIG. 2 is a side view of a guide.
FIG. 3 is a bottom view of a guide.
FIG. 4 shows the top view of a guide.
FIG. 5 shows a front view of a guide.
FIG. 6 shows a rear view of a guide.
FIG. 7 is a side view of a pocket loom.
FIG. 8 is a side view of a pocket loom with a depth adjuster.
FIG. 9 is a side view of an alternative embodiment of the pocket loom.
FIG. 10 is a top view of the preferred embodiment of the pocket loom.
FIG. 11 shows a front view of a pocket loom.
FIG. 12 shows a front view of an alternative embodiment of a pocket loom.
FIG. 13 a shows a side view of an alternative embodiment with guides perpendicular to the thongs.
FIG. 13 b shows a front view of an alternative embodiment with guides perpendicular to the thongs.
FIG. 14 shows an alternative embodiment for a guide using thong supports.
FIG. 15 is a top view of the present invention with an unstrung lacrosse stick head placed around it.
FIG. 16 is a top view of the present invention with a strung lacrosse stick head placed around it. The side walls and shooting strings are not shown.
FIG. 17 shows a flow diagram of the preferred steps for using the present invention.
FIG. 18 shows a thong with two holes.
FIG. 19 is a front view of a guide with ridges.
FIG. 20 is a top view of a guide with ridges.
FIG. 21 shows a technique of weaving a nylon string between a side wall and a thong.
FIG. 22 a shows a technique of interlacing a nylon string.
FIG. 22 b shows the results of interlacing a nylon string.
FIG. 23 shows a technique for weaving a shooting string.
DESCRIPTION OF THE PREFERRED EMBODIMENT
To explain the present invention, the description of the preferred embodiment provides: a brief description of a traditional lacrosse pocket; a detailed description of the components within the present invention; and a detailed description of how to use the present invention, in that order.
A traditional pocket is explained because the present invention is a method and apparatus for stringing traditional pockets 70 . As shown in FIG. 1, a traditional pocket 70 generally comprises an interlaced string 50 , a shooting string 55 , two side walls 57 , and four thongs 60 . The interlaced string 50 is preferably nylon, but can also be a variety of other natural or man-made materials. The thongs 60 are usually made of leather, but they may also be nylon or a variety of other natural or man-made materials.
The present invention is an apparatus and method for stringing the head 75 of a lacrosse stick with a traditional pocket 70 easier, and producing a higher quality traditional pocket 70 . As shown in FIG. 2, the present invention can comprise a guide 110 with a plurality of notches 150 .
The guides 110 can be made of metal, wood, plastic, or a variety of other materials. It is preferred the material be relatively stiff and rigid. The guides 110 usually have a front end, back end, flat side, curved side, and a plurality of T-shaped supports 124 . A T-shaped support 124 is the portion of the guide 110 creating the notches 150 . Preferably, a guide 110 is wider in the middle 120 than at the edges in order to make the shape of a pocket for a lacrosse stick, but the location of the widest portion 120 of a guide 110 may vary depending on where the user wants the ball (not shown) to rest in the pocket.
As shown in FIG. 3, the bottom of a guide 110 is preferably rectangular. In the preferred embodiment, the bottom portion 112 of the guide 110 is probably an inch or two thick and four to nine inches long. In contrast, FIG. 4 shows the top portion 115 of the guide 110 which is preferably approximately an eighth of an inch thick or less. FIGS. 5 and 6 show a guide from a front and rear view, respectively.
The notches 150 on a guide 110 are preferably spaced evenly along the curved side of the guide 110 , but the distance between the notches 150 may vary depending on where the user desires to interlace 80 the nylon 50 on the thongs 60 (i.e., the nylon placement), shown in FIG. 1 . The spacing between the notches 150 on different guides 110 may also vary depending on the type of pocket the user prefers. The notches 150 are preferably small at the top to assure the nylon placement is consistent in every pocket. The bottom portion of the notches 150 are wider to enable the user to interlace the nylon at the desired nylon placement. In the preferred embodiment the wider portion of the notches 150 are circular, but in alternative embodiments the notches could have a variety of shapes, such as square, rectangular, hexagonal, or diamond.
As shown in FIG. 7, in the preferred embodiment, a plurality of guides 110 can be connected with a base 130 to form a pocket loom 100 . FIG. 8 shows a pocket loom 100 with a depth adjuster 190 . The depth adjuster 190 usually includes a hinge 170 and an adjustable arm 160 . The hinge 170 allows the user to change the angle of the pocket loom 100 relative to the platform or working surface 195 . In the preferred embodiment, the adjustable arm 160 is a screw and two nuts. One of the two nuts is not shown, but is located in the working surface 195 . The other nut 162 is located at the end of the screw 160 , opposite the head of the screw, to prevent the screw 160 from coming out of the working surface 195 . By adjusting or turning the screw 160 into the nut 162 , the front of the pocket loom 100 is lowered, decreasing the depth of the pocket created by the pocket loom 100 and reducing the angle between the base 130 and the working surface 195 . By turning the screw 160 in the opposite direction, the front of the pocket loom 100 is raised, increasing the depth of the pocket made by the pocket loom 100 and increasing the angle between the base 130 on the working surface 195 . In an alternative embodiments, the depth could be adjusted by simply propping the front of the pocket loom 100 up in relation to the back or changing the shape of the guides 110 . As shown in FIG. 9, the guide 110 can be shaped at a desired angle without using the depth adjuster 190 . An embodiment which may be preferable if the user always wants the same pocket.
As shown in FIG. 10, the preferred embodiment contains four guides 110 , 110 ′, and a base 130 . However, in alternative embodiments, the pocket loom 100 may contain anywhere from two to six guides 110 . In the preferred embodiment, the pocket loom 100 contains two inner guides 110 ′ and two outer guides 110 . The two inner guides 110 ′ are generally equal in length (approximately eight and three-quarters inches), width (approximately two and one-half inches to four inches), and depth (approximately one eighth of an inch to one half inch). The back ends 225 of the two inner guides 110 ′ are positioned slightly closer than the front ends 226 to replicate the position of the thongs 60 within a pocket.
The two outer guides 110 are a little shorter than the inner guides 110 ′ (approximately eight inches), a little thinner (as shown in FIG. 7 ), and equal in depth. These two outer guides 110 are positioned on the outside of the two inner guides 110 ′. The back end 225 of the outer guide 110 is slightly closer to the back end 225 of its adjacent inner guide 110 ′ than the front end 226 of the outer guide 110 is to the front end 226 of the inner guide 110 ′, so that the guides 110 , 110 ′ converge towards the bottom of the pocket and diverge at the top.
As shown in FIGS. 7, 8 , 10 and 11 in the preferred embodiment, these guides 110 , 110 ′ are all connected by a base 130 . The base 130 is used to maintain the position of the guides 110 , 110 ′ in relation to each other and improve the users ability to create the same pocket time after time. The base 130 also maintains the location of the notches 150 in one guide 110 to the notches 150 in the adjacent guides 110 , 110 ′. As shown in FIG. 10, the notches 150 in one guide 110 are usually offset from its adjacent guides 110 , 110 ′. The position of these notches 150 in relation to each other is important because they assist the user in creating the diamond shaped weave 80 (shown in FIG. 1) of a traditional pocket 70 . An alternative embodiment is shown in FIG. 12, where the base 130 is thicker to add stability. In another embodiment, the guides 110 may slide into a base or fit into slots located at the top of the base. When connected in this manner, the guides 110 , 110 ′ are interchangeable within the same base 130 . This allows for changing the shape of the pocket without changing the base 130 .
Although the guides 110 , 110 ′ are usually attached in the form of a pocket loom 100 , they may be used separately. The purpose of using them separately is to facilitate the user's ability to create a variety of customized pockets without using several pocket looms 100 . For example, some lacrosse players desire deeper pockets than others. With separate guides, a user could simply replace the two inner guides 110 ′ with wider inner guides and reuse the same outer guide 110 and create a wider pocket.
In an alternative embodiment, as shown in FIG. 13 a , guides 110 , 110 ′ may also be positioned perpendicular to the thongs 60 . In this embodiment, as shown in FIG. 13 b , the guides 110 , 110 ′ are curved to resemble the shape of a pocket. The grooves are all aligned to hold a thong in the proper position to shape the pocket. The grooves holding the thongs at the bottom of the head are generally closer to replicate the slightly fan-shaped configuration of the thongs.
In another alternative embodiment, as shown in FIG. 14, guides may also be replaced with thong supports 400 connected by a frame 420 . The thong supports 400 are used to support a thong. The thong supports 400 have flat ends 410 to hold the thongs in the shape of a pocket. The other end of the thong supports 400 are mounted in a frame 420 to maintain their position in relation to each other. The thong supports 400 can be fixed to the frame 420 , or placed in holes within the frame 420 to make them removable or adjustable. If these thong supports 400 are removable, the user could insert different thong supports 400 within the same frame 420 to create different pockets. The number of thong supports 400 used and the length of the flat ends 410 may vary depending on the type of pocket desired by the user. The thong supports and frame can be made of a variety of rigid materials, including wood, plastic, and metal.
The space between the ends of the thong supports are preferably small to control the placement of the interlaces and wider at the bottom to permit the user enough room to interlace the nylon string. Similar to the notches, the chamber created between the thong spaces can be a variety of shapes.
To use the pocket loom 100 described above, as shown in FIG. 15, 16 and 19 , the head 75 of a lacrosse stick, such as the head shown in U.S. Pat. No. 5,566,947, issued Oct. 22, 1996 under the name of Tucker et al., is placed over the curved side of the pocket loom 100 with the holes for the side walls facing up. U.S. Pat. No. 5,566,947 issued Oct. 22, 1996 and entitled LACROSSE STICK HAVING OPEN SIDE WALL STRUCTURE is incorporated herein by reference. As shown in FIG. 17, the side walls (not shown) and thongs 60 are usually already installed 620 or woven onto the head 75 before the head is placed 628 over or around the pocket loom 100 , but they can also be installed after the head is placed over the pocket loom 100 . The side walls are usually fixed in some manner to the base of the head. The side walls are for example, installed by tying a hitch knot or a variety of other types of knots at one end of the nylon string and inserting it through a hole in one side of the base of the head from the outside of the head. That side wall or string is then fed into the adjacent hole from the inside of the head. Next, the side wall is threaded 620 behind the portion of side wall between the first and second holes, before being threaded into the third hole from the inside of the head. To install the side wall, this procedure is continued until the side wall reaches the top of that side of the head and is fixed or tied off with a knot. Similarly, another side wall is installed on the opposite side of the head.
As for the installation of a thong 60 , as shown in FIG. 18, about a two inch portion 500 of the thong 60 with two holes 505 , 507 cut in the middle of it, is inserted through one of the four holes at the top of the head. The two inch portion 500 is then double backed toward the bottom of the head. Then the other portion 501 , usually at least nine inches long, is threaded through the first hole 507 in the two inch portion, then it is weaved back through the second hole 505 (to prevent the end of the two inch portion from interfering with the performance of the stick). Then the long portion 501 is threaded into a hole at the bottom of the head corresponding to the same hole in the top of the head. Once the thong 60 is threaded through the hole at the bottom of the head, the long portion 501 can be tied off with a hitch knot or other type of knot. Depending on the depth of the pocket desired, some slack should be left in the thong 60 before tying it off at the bottom of the head. For another description of the installation of the side walls and the thongs, see U.S. Pat. No. 4,861,042, issued on Aug. 29, 1989 in the name of Douglas F. Trettin, incorporated herein by reference.
The thongs 60 should be attached loosely until they are aligned 640 with the guides 110 , 110 ′ as shown in FIG. 16, at the desired pocket depth and shape. When the thongs are positioned at the depth desired by the user, the user should tie the bottom ends 315 of the thongs 60 so they do not slip during stringing. During stringing, the thongs 60 may also be held from slipping by the means for securing 200 , such as the ridges shown in FIG. 19 and 20, ties, or clips. A ridge may run the entire length of the guide 110 . However, a means for securing 200 is not required if the bottom ends 315 of the thongs 60 are tied tightly against the guides 110 , 110 ′ because friction will stop the thongs 60 from slipping.
Once the thongs 60 are aligned with the guides 110 , 110 ′ as shown in FIG. 16, the user can weave 650 the nylon 50 between the side wall (not shown) and the thongs 60 to create a pocket. One technique of weaving the nylon 50 in this manner is shown in U.S. Pat. No. 4,861,042 (incorporated herein by reference). The nylon placements are made where the notches 150 on the guides 110 110 ′ are located. As stated earlier, the notches 150 are wider at the bottom to give the weaver more room.
With a traditional-style pocket, the person stringing the pocket usually starts weaving the nylon 50 from the bottom of the head 75 between a side wall 57 and its adjacent thong 60 . When the nylon 50 reaches the top of the head 75 , the nylon 50 is weaved between the first thong 60 and the second thong 60 toward the bottom of the head 75 . This procedure is continued until the nylon 50 reaches the top of the head 75 on the opposite side from the starting place.
The weaving is started by fixing or tying a hitch knot or other knot in one end of the nylon string. Then, the nylon is threaded through a hole on one side on the bottom of the head, like a side wall weave. Next, as shown in FIG. 21, the nylon 50 is woven around the outer thong 60 . After the nylon string 50 is wrapped completely around the outer thong 60 , it is threaded behind and under itself. Next, the nylon string 50 is woven around the side wall 57 in the same manner. Using this technique, the nylon 50 alternates between the outer thong 60 and the side wall 57 until it reaches the top. How many times it alternates depends on how many notches are in the guide supporting that thong 60 .
When the nylon string reaches the top of the head 75 , the user repeats the same procedure between the outer thong and the inner thong until it reaches the bottom/base of the head. The only differences is that when the nylon string 50 is woven around the outer thong 60 on the way back down, it is interlaced with itself, as shown in FIG. 22 a . The results of the interlaced nylon string 50 is shown in FIG. 22 b . The nylon string 50 that is woven into the pocket may be one piece or several pieces of nylon string.
This procedure is continued between the first and second inner thongs, then between the second inner thong and the second outer thong, and then between the second outer thong and the second side wall. After the nylon weaving is complete, the user can install the shooting strings. As shown in FIG. 23, the shooting string 55 is a nylon string braided across the top part of the head 75 . Usually, the shooting string 55 is first braided 710 from one side of the head to the other, and then back in parallel about a half an inch above or below the first pass. The shooting string 55 usually controls the release of the ball.
The foregoing description of the present invention has been presented for purposes of illustration and description. The description is not intended to limit the invention to the forms described. Variations and modifications commensurate with the above teachings, and within the skill and knowledge of the relevant art, are part of the scope of the present invention. | An apparatus and method for stringing traditional pockets for a lacrosse stick is disclosed. The apparatus comprises a plurality of guides that hold thongs typically used in a traditional pocket of a lacrosse stick at any depth desired by a user and guides the user in the nylon placement during stringing. The guides can also be customized to produce a variety of different shaped pockets. The apparatus and method greatly decrease the skill required to install a high quality traditional pocket in a lacrosse stick. The apparatus and method also increase the consistency in the shape of the pocket. For example, the apparatus and method enable the user to replicate the same pocket for numerous lacrosse sticks because the depth of the thongs and the nylon placement are controlled. In other words, the apparatus and method remove the most influential variables associated with the installation of a traditional lacrosse pocket. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to weighing scales, and more particularly to portable scales that resemble cargo pallets mounted to pallet trucks and that can accurately weigh loads of several thousand pounds.
2. Description of Related Art
Trucking and other shipping companies often charge their customers according to the weight of shipments. So it is important to both the shipper and customer that the weight of a shipment be accurately determined at convenient places.
Typical cargo units are loaded onto trucks using forklifts because they can weigh as much as 5,000 pounds. A scale strong enough and accurate enough to weigh such forklift pallet loads can weigh 200 to 400 pounds itself. So moving such a scale around a loading dock or out to a customer pickup location is very awkward and difficult.
A platform weighing scale is described by Herbert Wagner, et al., in U.S. Pat. No., 3,935,913, issued Feb. 3, 1976. Such platform weighing scale has a reinforced load cell-supported platform with a frame-like reinforcement. A load-receiving deck or platform is used to define a torsion box frame which resists load-induced deflection of the platform between the load-cell support points. Low profile platform scales for weighing relatively heavy loads are short in overall height, as measured from the floor or other scale-support surface to the top of the load-receiving platform or deck. Scales of this type are especially suitable for weighing loads which are carted by such vehicles as tote bins, push carts, dollies, fork lift trucks and other usually relatively small motor vehicles. Conventional low-profile type platform scales normally do not require installation in a pit to accommodate load-carrying vehicles and roll-on loads in general because the platform is relatively close to the floor surface and can easily be accessed by relatively short, gently sloped ramps. Herbert Wagner, et al., observed that low profile type platform scales offer an advantage of not needing to be installed in a pit. On the other hand, in installations where it is desired to locate the platform flush with the floor surface, only a shallow pit is needed.
U.S. Pat. No., 3,587,761 issued Jun. 28, 1971 to L. C. Merriam, et al., uses a special structure interposed between each load cell and the platform to avoid side loading of the cells. Such patent illustrates a typical platform structure having a deck plate and reinforcing beams which are seated on the platform-supporting load cells. Other examples of prior weighing scales are shown in U.S. Pat. No., 3,103,984, which issued to C. L. Ellis, et al., on Sep. 17, 1963; U.S. Pat. No., 2,962,276, which issued to A. L. Thurston on Nov. 29, 1960; U.S. Pat. No., 3,679,011, which issued to I. M. Hawver on Jul. 25, 1972; and, U.S. Pat. No., 3,565,196, which issued to E. Laimins on Feb. 23, 1971.
The prior art has discussed the ill-effects of side loading forces applied to load cells. Such side loading can adversely effect accuracy, and some can permanently damage the load cell. A few researchers have proposed solutions, e.g., U.S. Pat. No. 4,611,677, issued Sep. 16, 1986, titled, Shock Proof Scale; U.S. Pat. No. 4,305,475, issued Dec. 15, 1981 titled, Weigh Block Assembly; U.S. Pat. No. 4,453,607, issued Jun. 12, 1984, titled, Weight Scale With Side Load Protection; U.S. Pat. No. 4,601,356, issued Jul. 22, 1986, titled, Suspended Platform Scale Structure; and, U.S. Pat. No. 4,248,317, issued Feb. 3, 1981 titled, Load Cell Apparatus
SUMMARY OF THE INVENTION
An object of the present invention is to provide a portable weighing system.
Another object of the present invention is to provide a portable weighing system in which the dolly and lift mechanisms protect the corner load cells from damaging side impacts.
A further object of the present invention is to provide a dolly and lift mechanism that protect the corner load cells on low-profile platform scales from damaging side impacts.
A still further object of the present invention is to provide a dolly and lift mechanism for transporting and operating low-profile platform scales used with truck cargoes.
Briefly, a weighing system embodiment of the present invention comprises a floor dolly and lift mechanism that allow a heavy low-profile platform scale to be used practically anywhere truck cargoes need to be weighed. The low-profile platform scale includes a shear-beam load cell on each of four corners that are lifted off the ground by the lift mechanism whenever the dolly is being rolled to a job. The weighing system puts weight on each of the shear-beam load cells only when the lift system has lowered the low-profile platform scale onto a protective outrigger runner on each side and such runners are resting on the ground. Such runners have turned up steel wings that prevent side impacts to the shear-beam load cells. Various guides and pins keep the low-profile platform scale centered over the floor dolly and lift mechanism so that when it is lowered it will drop properly on the two outrigger runners and minimize contact between the lift mechanism and dolly during the weight mode.
An advantage of the present invention is that a weighing system is provided that is very portable and useful aboard a delivery truck in the field.
The above and still further objects, features, and advantages of the present invention will become apparent upon consideration of the following detailed description of specific embodiments thereof, especially when taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a portable weighing scale system embodiment of the present invention;
FIGS. 2A-2B are cross-sectional views at various operational times of a pallet-type scale that is similar to the weighing system of FIG. 1. FIG. 2A represents the low-profile platform scale being assembled to the steerable floor tug. FIG. 2B represents a transport mode. FIG. 2C represents a weighing mode;
FIG. 3 is a top view of a steerable floor tug embodiment of the present invention, similar to those shown in FIGS. 1 and 2A-2C; and
FIG. 4 is a schematic diagram of the interconnections between the four load cells, an electronic summer, and an indicator unit in a system similar to those shown in FIGS. 1, 2A-2C and 3.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a portable weighing scale system embodiment of the present invention, referred to herein by the reference numeral 100. The portable weighing scale system 100 comprises a load platform 102 that has four shear-beam load cells, one in each corner. The load platform and four load cells can be commercially supplied units. For example, the 6600 model-series ultra low profile floor scale marketed by the Pennsylvania Scale Company (Leola, Pa. 17540 USA) which uses four Sensortronics, Inc. (Covina, Calif. 91722 USA), premium load cells with load cell trimming. Such scales are typically available in platform sizes ranging from 24×24" (61×61 cm) to 60×60" (152×152 cm), and weighing capacities from 1000 lb./500 kg to 5,000 lb./2500 kg. The load platform 102 has a safety diamond-plate deck surface in preferred embodiments.
Each load cell has a downward protruding load-cell foot attached, as represented by the three load cell feet 104, 106, and 108, visible in the perspective of FIG. 1. The four load-cell feet on each side, left and right, are raised above and lowered onto a pair of respective outrigger runners 110 and 112. Such load-cell feet are raised from the outrigger runners 110 and 112 by a dolly 114 when the system is to be moved along the ground. Such outrigger runners 110 and 112 rest on the ground otherwise and the load-cell feet rest on top of them when taking weight measurements.
When a load is to be weighed that is resting on the load platform 102, the load-cell feet are lowered onto the top surfaces of the outrigger runners 110 and 112 by the dolly 114. In the transport mode, such outrigger runners 110 and 112 are designed to drop a bit and this helps provide clearance under the load-cell feet. A handle 116 with a grip 118 allows the dolly 114 to be tugged and steered over a concrete floor into position. A control and display module 120 allows a user to turn on the load cells and see a digital readout of the estimated weight on the load platform 102. The control and display module 120 may be a commercially supplied unit, e.g., the STANDARD indicator by Ohaus Corporation (Florham Park, N.J. 07932 USA).
The outrigger runners 110 and 112 are shown in FIG. 1 with end and side shields that can help to guard the load cell feet from receiving an accidental damaging side impact.
FIGS. 2A-2B are cross-sectional views of a low-profile portable platform scale and dolly 200 which is similar to the weighing system 100 in FIG. 1. A low-profile platform scale 202 is carried by a steerable floor tug dolly 204. FIG. 2A shows the two separated so that FIGS. 2B and 2C will make more sense. A vertically expandable lift unit 206 has a pair of upwardly cupped outrigger runners 208 and 210 supported like wings on struts. A set of four wheels, groups 212-214 are distributed in a tricycle arrangement, and the tandem-wheel group 213 is steerable.
Internal hydraulic units and lift pivots allow the lift unit 206 to raise its upper shell and a top surface 216 to press up against an inside surface 218 of the platform scale 202, as shown in FIG. 2B. Such lifting up will also raise up the outrigger runners 208 and 210 by their struts. A pair of frame channels 220 and 222 that are used mainly to stiffen the platform scale 202 do double duty in keeping the lift unit 206 centered underneath. FIG. 3 shows how pins (344-347) are used to help glide the interface of the top of the lift unit 206 inside the channels 220 and 222 such that snags and hang-ups will not occur that could interfere with the accuracy of the scale.
A left-side shear beam load cell 224 and foot 226 either rest on the outrigger runner 208, as shown in FIG. 2C, or are lifted off by the lift unit 206 as shown in FIG. 2B. Similarly, a right-side shear beam load cell and foot 228 and 230 can rest on the outrigger runner 210, as shown in FIG. 2C, or be lifted off by the lift unit 206 as shown in FIG. 2B. FIGS. 2B and 2C show the detail of a well in the outriggers 208 and 210. The feet 226 and 230 will remain inside the well during all times, and drop to the floor of the well during weighing mode, as in FIG. 2C.
FIG. 2C represents the condition where the lift unit 206 has collapsed down and there is a clearance gap left between surfaces 216 and 218. All the weight of a load 232 will therefore be transferred to ground through only the load cells 224 and 228, then through the corner feet 226 and 230, and through the two outrigger runners 208 and 210. In preferred embodiments of the present invention, the load 232 has the clearance all around needed to overhang any of the edges of the platform scale 202.
FIG. 3 represents a top view of a steerable floor tug dolly 300, which is similar to floor tug dolly 204 in FIGS. 2A-2C. The steerable floor tug dolly 300 comprises a tricycle arrangement of three wheels 301-303. Wheel 301 can be a single wheel in the middle of a pivot 304 or a tandem pair of wheels on either side as shown in FIG. 3. A left wheel 302 is attached to a left support plate 306. A right wheel 303 is attached to a right support plate 308. A pair of left struts 310 and 312 support a left outrigger runner 314. A pair of right struts 316 and 318 support a right outrigger runner 320. The pivot 304 can be tugged and steered over a flat floor by a handle 322 with a handgrip 324. A set of four landing areas 326-329 provide a resting place for load cell feet, e.g., such as is illustrated in FIG. 1 for load cell feet 104, 106, and 108, to rest on outrigger runners 110 and 112. The general structure of the steerable floor tug dolly 300 is made of steel, and the outrigger runners 314 and 320 in a prototype were made of u-channel steel sections with plates welded on top to provide for landing areas 326-329. A hydraulic piston 330 is deflated by a release pedal 332 that opens a relief valve, and inflated by a pump-lift pedal 334 that operates a pump. Both the pedals 332 and 334 are equipped with stiff return springs so that they can be foot operated by a user. A shaft 336 connected to the hydraulic piston 330 pushes a lifting arm 338 to rotate and raise the carriage assembly, outrigger assembly, runners and load platform off the ground. A link 340 couples the force of the hydraulic piston 330 to a second rotating lift arm 342 so that the lifting action will maintain any load-weighing platform carried on the backs of the side plates 306 and 308 parallel to the ground.
Referring to the platform scale 200 in FIGS. 2A-2C for a moment, it is critical that the joint between the low-profile platform scale 202 and the steerable floor tug dolly 204 be free floating and able to slide without hanging up when changing from transport mode to weighing mode. So in FIG. 3, the steerable floor tug dolly 300 includes a set of clearance pins 344-347 on the opposite sides of support plates 306 and 308 near the top edges. These prevent a frictional full-surface contact between the vertical surfaces of the low-profile platform scale 202 and the steerable floor tug dolly 204 from interfering with the weight measurement. All the weight of the load 232 must be seen by the load cells in combination and not bypassed by some mechanical snag that might occur. The set of clearance pins 344-347 act as guides and provide for a centering of the platform scale over the lift frame during transitions from said transportation mode to said weighing mode.
A set of four end-and-side guards 350-353 shield the outside approaches to load cell foot landing areas 326-329. These guards protect the shear-beam load cells in the platform scale from receiving accidental damaging side impacts. Alternatively, the runners 314 and 320 could be cupped structural pieces, such as U-channel steel or aluminum with the ends closed off.
In alternative embodiments of the present invention, the wheels 302 and 303 are equipped with brakes that can be set and released with a hand-lever brake at the handgrip 324.
In still other alternative embodiments of the present invention, the release pedal 332 is replaced by a hand-lever release mounted to the handgrip 324.
Embodiments of the present invention share a unique way that the platform scale feet interface with the outrigger runners, or carriage legs. During weighing operations, the platform scale feet are lowered to rest firmly on the carriage legs. However in the transport mode, the platform scale feet are lifted off so they do not contact the carriage legs. This is important for two reasons, hysteresis and mechanical damage.
Load cells and strain gauge sensors work best when the forces acting on them are limited to the vertical axis. Any forces applied to one side, e.g., in any horizontal axis, can cause such sensors to develop a hysteresis where the sensor will not always return to the same "zero" point. This makes any measurements obtained inaccurate. One company, Mettler/Toledo scale company, has recently promoted a "rocker pin assembly" for their platform scales to deal with this issue.
Since even modest side impacts and knocks can effect any shear-beam load cell's accuracy, then a severe horizontal force caused by a collision with another object could cause serious and permanent damage to the load cell. Embodiments of the present invention therefore avoid having an exposure or a mechanical joint between the load cell sensor foot and the outrigger runner or carriage leg. The carriage leg will take the brunt of any horizontal impacts.
FIG. 4 represents the electronics that can be used with the systems illustrated in FIGS. 1, 2A-2C, and 3. An electronic weighing system 400 is used to instrument a low-profile weighing platform 402 that resembles a steel pallet on a pallet floor truck with a hydraulic lift. The weighing platform 402 is generally rectangular or square, e.g., 36" by 36" or 36" by 48", and has a shear-beam load cell 404-407 in each corner. The overall height of a typical system is less than six inches, not counting a tug handle. The individual weight measurements contributed by each load cell 404-407 are summed or added by an electronic summing unit 408. The product of the four weight measurements is digitally displayed to the nearest pound by a scale readout 410, e.g., an Ohaus model I-10. A typical scale system 400 will weigh up to 5,000 pounds. A battery 412 allows the electronic weighing system 400 to operate in any location.
Although particular embodiments of the present invention have been described and illustrated, such is not intended to limit the invention. Modifications and changes will no doubt become apparent to those skilled in the art, and it is intended that the invention only be limited by the scope of the appended claims. | A portable platform-scale weighing system comprises a floor dolly and lift mechanism that allow a heavy low-profile platform scale to be used practically anywhere truck cargoes need to be weighed. The low-profile platform scale includes a shear-beam load cell on each of four corners that are lifted off the ground by the lift mechanism whenever the dolly is being rolled to a new job. The weighing system puts weight on each of the shear-beam load cells only when the lift system has lowered the low-profile platform scale onto a protective outrigger runner on each side and such runners are resting on the ground. Such runners have turned up steel wings that prevent side impacts to the shear-beam load cells. Various guides and pins keep the low-profile platform scale centered over the floor dolly and lift mechanism so that when it is lowered it will drop properly on the two outrigger runners and minimize contact between the lift mechanism and dolly during the weight mode. | 6 |
FIELD OF THE INVENTION
[0001] The invention relates generally to hard disc drives and more particularly to an impact shock absorbing hard drives.
BACKGROUND OF THE INVENTION
[0002] As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
[0003] Hard disc drives are a common source of field failures in information handling systems such as computer systems. Within a hard disc drive are several thin discs, i.e., magnetic media, each having an associated flying head, thus, making hard disc drives sensitive to impact. This is particularly true when the hard disc drive is removable and the impact occurs when the hard disc drive is separate from the computer system.
[0004] Upon impact, the heads of the hard disc drive may bounce and contact the discs. The discs may be either broken or scored by such impact. Loose particles may also result from such impact and become free to move around inside the hard disc drive and contact other parts of the hard disc drive thus causing new failures. Furthermore, such impacts may cause shock to the entire hard disc drive housing, not just to the heads.
[0005] Attempts to cushion hard disc drives against shock from impact include providing elastomer feet on the bottom or rest surface of the computer system for providing a cushioning effect of the portable computer housing on an associated support surface. These feet serve as friction surfaces to limit lateral movement of the computer system relative to its support surface. Cushioned mounts provide vibration damping but have not addressed the issue of where such mounts should be located to provide maximum protection from impact shocks.
SUMMARY OF THE INVENTION
[0006] Accordingly, a disc drive system which includes cushioning material positioned between the interior of disc drive housing and a disc drive advantageously provides a removable disc drive system which isolates shocks from the disc drive.
[0007] In one embodiment, the inventions relates to a disc drive system which includes a housing bottom, a mounting plate coupled to the housing bottom, and a disc drive coupled to the mounting plate via cushioning pieces.
[0008] In another embodiment, the invention relates to an information handling system which includes a processor, a memory and a disc drive system. The memory is coupled to the processor. The disc drive system includes a housing bottom, a mounting plate and cushioning pieces. The mounting plate is coupled to the housing bottom. The disc drive is coupled to the mounting plate via cushioning pieces.
[0009] In another embodiment, the invention relates to a removable hard drive which includes a housing top, a housing bottom, a mounting plate, a disc drive and cushioning pieces. The housing bottom is coupled to the housing top. The mounting plate is coupled to the housing bottom. The disc drive is coupled to the mounting plate via cushioning pieces.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The present invention may be better understood, and its numerous objects, features and advantages made apparent to those skilled in the art by referencing the accompanying drawings. The use of the same reference number throughout the several figures designates a like or similar element.
[0011] [0011]FIG. 1 shows a diagrammatic schematic view of an information handling system.
[0012] [0012]FIG. 2 shows a top view of a hard disc drive system without the cover of the hard disc drive housing.
[0013] [0013]FIG. 3 shows an assembly view of a hard disc drive system.
[0014] [0014]FIG. 4 shows another assembly view of a hard disc drive system.
DETAILED DESCRIPTION
[0015] For purposes of this invention, an information handling system may include any instrumentality or aggregate of instrumentalities operable to compute, classify, process, transmit, receive, retrieve, originate, switch, store, display, manifest, detect, record, reproduce, handle, or utilize any form of information, intelligence, or data for business, scientific, control, or other purposes. For example, an information handling system may be a personal computer, a network storage device, or any other suitable device and may vary in size, shape, performance, functionality, and price. The information handling system may include random access memory (RAM), one or more processing resources such as a central processing unit (CPU) or hardware or software control logic, ROM, and/or other types of nonvolatile memory. Additional components of the information handling system may include one or more disk drives, one or more network ports for communicating with external devices as well as various input and output (I/O) devices, such as a keyboard, a mouse, and a video display. The information handling system may also include one or more buses operable to transmit communications between the various hardware components.
[0016] Referring to FIG. 1, information handling system 100 , includes a processor 102 , which is coupled to a bus 104 . Bus 104 functions as a connection between processor 102 and other components of computer system 100 . An input system 106 is coupled to processor 102 to provide input to processor 102 . Examples of input devices include keyboards, touchscreens, and pointing devices such as mouses, trackballs and trackpads. Programs and data are stored on a mass storage device 108 , which is coupled to processor 102 . Mass storage devices include such devices as hard disc drives, optical disks, magneto-optical drives, floppy drives and the like. Computer system 100 further includes a display 120 , which is coupled to processor 102 via a video controller 122 . A system memory 124 is coupled to processor 102 to provide the processor 102 with fast storage to facilitate execution of computer programs by processor 102 . It will be appreciated that other buses and intermediate circuits can be deployed within and information handling system operation of the information handling system.
[0017] Referring to FIG. 2, hard disc drive system 200 includes a hard disc drive 210 as well as a hard disc drive housing bottom 212 . The hard disc drive 210 is coupled to the hard disc drive housing bottom 212 via a mounting plate 220 and cushioning devices 222 , which are constructed of, e.g., foam. In a preferred embodiment, the foam includes double sided adhesive and mounting plate 220 is attached to the housing 212 via the double sided adhesive foam. The adhesive foam absorbs shock energy and effectively reduces the shock experienced by the hard disc drive 212 if the hard disc drive system 200 receives a shock such as when the system is dropped. Accordingly, the cushioning devices 222 provide vibration dampening to the hard disc drive 210 if the hard disc drive system 200 receives any type of impact. The housing bottom 212 includes positioning members 230 which are located substantially at the corners of the mounting plate 220 . The positioning members 230 interact with the cushioning devices 222 to provide additional vibration dampening.
[0018] Referring to FIGS. 3 and 4, hard disc drive system 200 includes a housing top 300 , the hard disc drive 210 , mounting plate 220 , cushioning devices 222 and housing bottom 212 . Hard disc drive system 200 also includes cushioning devices 320 located between the top of the hard disc drive 210 and the housing top 300 . Hard disc drive system 200 also includes a housing eject mechanism (not shown) which allows the removable hard disc drive system to be removed from the computer system.
[0019] The hard disc drive 210 is attached to the mounting plate 220 via screws that are in locations defined by a hard drive industry standard. In a preferred embodiment, the cushioning devices 222 are formed in spheres so that the screws may be easily passed through the middle of the cushioning pieces 222 .
[0020] Other Embodiments
[0021] Other embodiments are within the following claims.
[0022] For example, if additional vibration dampening needs arise, the cushioning devices material may be added to other locations within the hard disc drive housing.
[0023] Also for example, it will be appreciated that the cushioning devices may be fabricated from a variety of different materials so long as the material provides sufficient cushioning function.
[0024] Also for example, it will be appreciated that additional positioning members may be located to interact with the sides of the mounting bracket. In this case additional cushioning devices are added to the mounting bracket to interact with the additional positioning members.
[0025] Also for example, while the cushioning devices are shown as spherical, it will be appreciated that other shapes (such as, e.g., squares or rectangles) may be used. With these shapes, a hole may be located within the cushioning device to allow for mounting of the hard disc drive to the mounting bracket. | The invention relates to a disc drive system which includes cushioning material positioned between the interior of disc drive housing and a disc drive. Such a system advantageously provides a removable disc drive system which isolates shocks from the disc drive. The disc drive system includes a housing bottom, a mounting plate coupled to the housing bottom, and a disc drive coupled to the mounting plate via cushioning pieces. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority from U.S. provisional patent application Ser. No. 60/931,577 filed May 24, 2007.
TECHNICAL FIELD
The present invention relates to a light emission device, comprising at least two light-emitting semiconductor chips and a substrate, at least one first semiconductor chip is fitted on the substrate and a second semiconductor chip is fitted on the first semiconductor chip.
BACKGROUND OF THE INVENTION
Numerous attempts have been made to increase the emission intensity of light emitting diodes. It has thus been proposed to arrange a plurality of very small light emitting diode semiconductor chips closely adjacent to one another in order to attain a higher luminous efficiency. A problem in this case, of course, is the heat dissipation, since the closely adjacent arrangement of the semiconductor chips means that the latter become very hot at corresponding power.
It has therefore been attempted to separate the light emission from the thermal radiation if possible and to cause the thermal radiation to be radiated principally toward the rear and, by contrast, the light emission toward the front.
Such considerations also give rise to the so-called flip-chip technique, which involves fitting one or a plurality of semiconductor chips onto a light-transmissive substrate, which may be made of sapphire or the like, by way of example.
A reflector layer, for example made of silver, extends on that side of the chip or chips which is remote from the sapphire, both the contact-connection and the heat dissipation being effected by means of very thick posts, so-called bumps, which make contact with the chip in a suitable manner.
In the case of this solution, the intention is then for as much heat as possible to be dissipated toward the rear if possible, while light, amplified by the silver reflection layer, is intended to leave the light emission device through the sapphire substrate toward the front.
Endeavors have also been made for a relatively long time to increase the optical efficiency of light emission devices. For this purpose, combinations of converging lenses and reflectors are usually used, which concentrate the emitted light and are intended to reduce the generation of spurious light and scattered light.
It has recently been proposed, for example, in accordance with German Patent Application 10 2006 015 377 to form a semiconductor radiation source with a plurality of LED chips which are contact-connected by means of a printed circuit board brought up close, wherein a reflector in combination with a converging lens is intended to ensure a highest possible luminous efficiency, but the generated heat is nevertheless intended to be dissipated well.
Although a semiconductor radiation source of this type is basically already highly suitable if it is necessary to ensure a highest possible luminous efficiency, it would be desirable, however, to improve the luminous efficiency even further without increasing the emission of heat.
OBJECTS AND SUMMARY OF THE INVENTION
Therefore, the invention is based on the object of providing a light emission device which is improved with regard to the light emission without an increase in the electrical power giving rise to problems in the dissipation of heat.
According to the invention, it is particularly expedient that a centrally intensified light emission can be generated by the stacked arrangement of LED chips. The focusing of such a central point of brightness is significantly easier than in the case of a planar distribution of the light emission, with the result that the luminous efficiency can be significantly increased overall.
This opens up an extended field of application for light emission devices, for example also in dental technology, where correspondingly constructed light curing devices make it possible to rapidly polymerize in a targeted manner specific regions of a polymerizable dental restoration that have not yet fully cured sufficiently.
Surprisingly, the light emission can be significantly increased by the stacked fitting of chips, use being made of the fact that the chip itself is transmissive to light. The transmissivity is particularly good for the same materials used since then the same lattice constant is present there. The invention provides for forming a very thin and light-transmissive adhesive layer between the semiconductor chips of the chip stack, said adhesive layer also having good thermal conductivity and therefore dissipating the heat of the upper chips well.
According to the invention, it is also possible to make use of the fact that a significant part of the light emission in semiconductor chips typically takes place via lateral light exit areas. The latter are preferably arranged so as not to impair the light emission obliquely toward the front. This can be achieved for example by the stack of semiconductor chips having an essentially pyramidal construction. The respective upper semiconductor chips are set back in each case relative to the respective lower semiconductor chips, that is to say are offset inward toward the optical axis. This is accompanied by a reduction of the dimensions of the upper semiconductor chips relative to the respective lower semiconductor chip, the reduction preferably being effected in both directions.
In a manner known per se, the semiconductor chips may be square and formed essentially as thin laminae. Semiconductor chips having different dimensions are readily available, such that it is possible in this respect to have recourse to commercially available components which can be combined in a particularly favorable manner according to the invention.
In this case, it is also possible to make use of the fact that the semiconductor chips typically have a Lambertian radiating characteristic that makes it possible, precisely upon superposing a plurality of such radiating characteristics that are spaced apart somewhat from one another in the vertical direction, that is to say in the light emission direction, to increase the light emission in the region of the optical axis in relative terms.
According to the invention, it is thus possible to significantly increase the proportion of the directly radiated light with respect to the proportion of the reflected light, with the result that reflector faults and the like are also less important.
In an advantageous configuration of the invention it is provided that at least one upwardly facing area of a lower semiconductor chip is not covered by the semiconductor chip situated thereon and remains free in this respect. Said area serves on the one hand for light emission; on the other hand this provides the possibility of providing a connection area for bonding, such that per semiconductor chip at least two connection areas are available for the electrical supply of the semiconductor chips. According to the invention, it is provided that the lower area is formed in a suitable manner for the heat dissipation. For this purpose, the lower semiconductor chip is at least not smaller and preferably larger than the semiconductor chip situated above it. Insofar as the semiconductor chip situated above it extends partially beyond the semiconductor chip situated underneath, this is effected on a spatially limited scale, in which case the sum of the self-supporting areas of the upper semiconductor chip should preferably make up less than 20% and in particular less than 10% of the total area.
It goes without saying that here semiconductor chip should be understood to mean a die in which it is also possible to combine a plurality of electrical structures which can also be connected to a plurality of connection areas.
It is particularly favorable if a converging lens is fitted above the topmost semiconductor chip.
The emitted light radiation can thereby be focused in a suitable manner, it also being readily possible according to the invention for the emitted light to be conducted into an optical waveguide such as a light guiding rod.
According to the invention, it is preferred for the arrangement of the semiconductor chips to be free of reflectors and reflection layers, apart from a reflection layer arranged below the bottommost semiconductor chip. Said reflection layer reflects the downwardly emitted radiation essentially completely and has an effect upward, it being preferred for the semiconductor chip arrangement to be surrounded by a ring reflector by means of which the radiation reflected in this way is additionally projected toward the front and focused.
According to the invention it is also readily possible to configure the stacked semiconductor chips such that they emit light in different wavelength ranges. For this purpose, it is possible to make use of the fact that each semiconductor chip is provided with connection areas. The electrical driving can thus be effected independently of one another, such that color changes can also readily be realized.
According to the invention, in the case of the preferred pyramidal construction of the semiconductor chip arrangement, use is also made of the effect that the bottommost semiconductor chip exhibits the highest light emission and, accompanying this, evolution of heat. The heat arising there can be dissipated very well on account of the direct mounting onto a substrate having a thermal conductivity, while the quantity of heat introduced in the case of semiconductor chips arranged further up is also smaller according to the smaller dimensions of said chips.
Since a compact arrangement of semiconductor chips is possible according to the invention, it is preferred to provide the provision of free areas for bonding on a printed circuit board directly adjacent to the semiconductor chips. For this purpose, the substrate preferably has a projection on which the bottommost semiconductor chip is fitted and up to the lateral area of which the printed circuit board is brought with its free area.
It is favorable in this connection if the structural height of the printed circuit board essentially corresponds to the height of the substrate base projection.
In a further advantageous configuration it is provided that the second as relatively upper semiconductor chip leaves free an upwardly facing area of the first as relatively lower semiconductor chip, and that at least the left-free area of the lower semiconductor chip and at least one area of the upper semiconductor chip are light-emitting, the lower semiconductor chip being fitted on the substrate.
In a further advantageous configuration it is provided that lateral light emission areas extend laterally at the chips, which are offset with respect to one another.
In a further advantageous configuration it is provided that a lateral light emission area of the upper semiconductor chip extends, relative to a lateral light emission area of the lower semiconductor chip, in a manner shifted toward the center of the semiconductor chip.
In a further advantageous configuration it is provided that the semiconductor chips are constructed essentially pyramidally with respect to one another.
In a further advantageous configuration it is provided that the semiconductor chips are at least partly transmissive to emitted radiation.
In a further advantageous configuration it is provided that the light emission device has a reflector fitted below the lower semiconductor chip, and that no reflector is provided between the lower, a middle, and the upper semiconductor chip.
In a further advantageous configuration it is provided that the light emission device has a plurality of semiconductor chips and a reflector is fitted below the bottommost semiconductor chip, which extends in particular laterally beyond the semiconductor chip.
In a further advantageous configuration it is provided that the semiconductor chips are connected to one another by means of a reflection-free adhesive layer having a thermal conductivity having approximately the same magnitude as the thermal conductivity of the semiconductor chips, the thickness of the adhesive layer being less than 100 μm and preferably less than 50 μm.
In a further advantageous configuration it is provided that a plurality of semiconductor chips which emit light having different spectral wavelengths are arranged one on top of another.
In a further advantageous configuration it is provided that the semiconductor chips are at least partly electrically connected in series with one another.
In a further advantageous configuration it is provided that the semiconductor chips are at least partly electrically connected in parallel with one another.
In a further advantageous configuration it is provided that the semiconductor chips have at least one electrical connection zone on their top side in the region of the left-free area.
In a further advantageous configuration it is provided that the substrate is electrically insulating and carries a reflection layer.
In a further advantageous configuration it is provided that the bottommost semiconductor chip is applied to an electrically at least semiconducting substrate, and that an electrical connection area of the bottommost semiconductor chip is formed by the substrate.
In a further advantageous configuration it is provided that the upper semiconductor chip is smaller than the lower semiconductor chip, in particular the size difference corresponding approximately to twice the thickness of each semiconductor chip.
In a further advantageous configuration it is provided that semiconductor chips fitted one on top of another are rotated relative to one another, in particular at an angle of, in particular, 45°.
In a further advantageous configuration it is provided that the substrate has a projection, the dimensions of which essentially correspond to the dimensions of the lower semiconductor chip and on which the lower semiconductor chip is fitted.
In a further advantageous configuration it is provided that an additional reflector, in particular a ring reflector, surrounds the semiconductor chips fitted one on top of another, the orientation of which reflector is oblique or parabolic in a manner known per se and which reflector reflects the lateral light emission of the semiconductor chips toward the front.
In a further advantageous configuration it is provided that a converging lens is fitted before the semiconductor chips, said converging lens being supported in particular on the reflector.
In a further advantageous configuration it is provided that the space between the semiconductor chips and the underside of the converging lens is filled by a transparent or translucent, liquid or gel-type light-transmissive substance, in particular silicone gel.
In a further advantageous configuration it is provided that the electrical connection areas are adjacent to free areas of a printed circuit board, to which areas they are electrically connected by means of bonding wires.
In a further advantageous configuration it is provided that a printed circuit board extends laterally alongside the semiconductor chips in a manner at least partly surrounding said semiconductor chips, and in particular runs with conductor tracks below a ring reflector.
Further advantages, details and features emerge from the following description of two exemplary embodiments of the invention with reference to the drawing.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows a schematic view of one embodiment of a semiconductor radiation source according to the invention in a perspective illustration;
FIG. 2 shows a view corresponding to FIG. 1 of a further embodiment of a semiconductor radiation source according to the invention;
FIG. 3 shows a partly sectional, likewise perspective illustration of a semiconductor radiation source in the embodiment in accordance with FIG. 2 , the illustration showing the embodiment in the installed state.
DETAILED DESCRIPTION
FIG. 1 reveals a light emission device 10 according to the invention in one embodiment. This light emission device 10 has a plurality of semiconductor chips, namely a lower semiconductor chip 12 , a middle semiconductor chip 14 and an upper semiconductor chip 16 . In this case, the lower semiconductor chip 12 , which may also be referred to as first semiconductor chip, is fitted onto a substrate, which can be seen from FIG. 3 by way of example.
The substrate may be configured in any suitable manner. It preferably dissipates heat that is particularly preferably metallic. However, it is also possible, in a solution with lower power, to use a plastic casting material as substrate, which then fixes the spatial arrangement of the semiconductor chips.
In the exemplary embodiment illustrated, the first or lower semiconductor chip 12 is formed as a lamina having an essentially square parallelepiped form. Such semiconductor chips or LED chips are readily commercially available.
In the exemplary embodiment illustrated, the lower semiconductor chip 12 and the middle semiconductor chip 14 have the ratio between edge length and thickness of approximately 8:1. They are identical in size and placed one on top of another, but rotated relative to one another. The rotation is effected at an angle of approximately 45°, but a rotational angle of 30° or 60° would also readily be possible.
As a result of the rotation, the middle semiconductor chip 14 leaves four triangular areas as left-free areas, the areas 20 , 22 and 24 being evident from FIG. 1 . The area remaining there suffices to provide in each case an electrical connection area 26 , 28 and 30 , which are in each case provided on the very far outer part and in circular fashion and are prepared for bonding.
In the exemplary embodiment illustrated, four connection areas are provided per chip, and the chip carries a total of three structures which can be driven independently of one another and which emit light, with the result that any driving arrangements are possible. As an alternative, provision may also be made for providing only two structures which can then be electrically isolated from one another and are connected in each case to a pair of connection areas.
In the exemplary embodiment illustrated, the upper semiconductor chip 16 is smaller than the middle and lower semiconductor chips 14 and 12 .
Its edge length/thickness ratio is likewise approximately 8:1, with the result that it is also thinner than the other two chips 12 and 14 .
It is rotated once again by 45° relative to the middle semiconductor chip 14 , with the result that it extends edge-parallel to the lower semiconductor chip 12 . This arrangement gives rise to further left-free areas 32 , 34 , 36 and 38 , which in each case have a triangular construction and also serve for contact-connection via corresponding connection areas 40 , 42 , 44 and 46 .
The upper semiconductor chip 16 is of a size such that it covers a significant part of the middle semiconductor chip 14 , for example 70% of its area.
The middle semiconductor chip 14 emits light on the one hand at its lateral emission areas, the emission areas 50 and 52 being evident from FIG. 1 , and on the other hand at its underside, but also in large part at its top side.
The light emitted below the upper semiconductor chip 16 passes through the latter and in this respect amplifies the light emitted on the top side 54 of the upper semiconductor chip 16 . In this case, it is possible expediently to make use of the fact that the thickness of the upper semiconductor chip 16 is somewhat smaller than that of the other two semiconductor chips 12 and 14 ; the attenuation when passing through the relevant chip 16 decreases as a result.
A corresponding light emission and passage behavior is also exhibited by the stacking of the middle semiconductor chip on the lower semiconductor chip 12 . Accordingly, the light emitted from the top side of the lower semiconductor chip 12 passes through both the middle semiconductor chip 14 and the upper semiconductor chip 16 insofar as it is not emitted in the region of the areas 20 to 24 .
In this case, too, light is additionally emitted at the lateral emission areas, the emission areas 56 and 58 being evident from FIG. 1 .
Semiconductor chips having a spherical radiating characteristic are preferably used. The radiating characteristics of the light emission device formed from the three semiconductor chips 12 , 14 and 16 essentially results as the computational summation of the emitted light intensities, considered over the angular deviation from the optical axis 60 . This idealized radiating characteristic, which exhibits a behavior approximated to a lobe, is in practice attenuated by the radiation absorption of the light emission of the lower semiconductor chips by the upper semiconductor chips. In the case of material identity, however, the attenuation is surprisingly markedly low, which in particular is probably attributable to the matching of the lattice constants.
FIG. 2 reveals a modified embodiment of a light emission device 10 according to the invention. In FIG. 2 and also in the rest of the figures, identical reference symbols indicate identical or corresponding parts. In the case of the embodiment in accordance with FIG. 2 , all the light conductor chips 12 , 14 and 16 are constructed pyramidally with respect to one another. The semiconductor chip 12 is the largest and is fitted on the substrate in thermally conductively connected fashion. The middle semiconductor chip 14 is applied on said semiconductor chip 12 , and it is smaller than the semiconductor chip 12 .
The differences in dimensions give rise to a peripheral free edge 62 , the width of which essentially corresponds to the thickness of the semiconductor chip 14 . The connection areas 26 , 28 , 30 and 31 of the lower semiconductor chip 12 are again fitted in the corners, the same correspondingly also applying to the connection areas 40 to 46 of the middle semiconductor chip 14 and the connection areas of the upper semiconductor chip 16 .
Since the upper semiconductor chip 16 is even smaller than the middle semiconductor chip 14 and is likewise fitted on the latter, there as well a peripheral edge 64 arises, the width of which in turn corresponds to the thickness of the semiconductor chip 16 .
This arrangement and configuration results overall in a truncated pyramid having a pyramid angle of approximately 45°.
The chips 12 to 14 are each applied on one another in thermal contact. This can be realized by a very thin adhesive layer, for example, which additionally improves the heat transfer.
FIG. 3 reveals a corresponding light emission device 10 in a sectional state and in an installed state. The light emission device 10 is fitted on a substrate 66 , which is composed of copper, for example, that has a base projection 68 . The base projection 68 has larger dimensions than the lower semiconductor chip 12 . It is adjoined by a printed circuit board 70 carrying free areas 72 of conductor tracks which serve for making contact with the various connection areas. By way of example, the connection area 28 can be connected to the free area 72 via the bonding wire (not illustrated)
Supported on the printed circuit board is a ring reflector 80 as an additional reflector, which annularly surrounds the light emission device. The ring reflector 80 has, in a manner known per Se, an inner area which faces obliquely inward and reflects light emerging from the lateral emission areas, for example the emission area 56 , toward the front, that is to say in the direction of the optical axis 60 .
A reflector is furthermore provided between the base projection 68 and the lower semiconductor chip 12 , which reflector cannot be seen from the illustration in the drawing and likewise projects the light impinging there toward the front.
While a preferred form of this invention has been described above and shown in the accompanying drawings, it should be understood that applicant does not intend to be limited to the particular details described above and illustrated in the accompanying drawings, but intends to be limited only to the scope of the invention as defined by the following claims. In this regard, the term “means for” as used in the claims is intended to include not only the designs illustrated in the drawings of this application and the equivalent designs discussed in the text, but it is also intended to cover other equivalents now known to those skilled in the art, or those equivalents which may become known to those skilled in the art in the future. | The invention relates to a light emission device, comprising at least two light-emitting semiconductor chips and a substrate. At least one first semiconductor chip ( 12 ) is fitted on the substrate and a second semiconductor chip ( 14 ) is fitted on the first semiconductor chip ( 12 ). | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to bituminous concrete and the methods of making same, and more specifically to sulfur-extended asphalt mix designs, processes, and apparatus for use with the same.
2. Description of Prior Art
Preliminarily, as used herein, the terms "asphalt" or "asphalt cement" shall mean any of the heavy petroleum oils or tar or pitch; "bituminous contrete" shall mean a composition of asphalt cement and aggregate (such as gravel, sand, mineral fillers, etc.); and "sulfer-extended asphalt" shall mean a mixture of sulfur and asphalt cement. Additionally, the term "binder content" shall mean, depending upon the context, either the weight of the asphalt cement alone or the weight of the sulfur-extended asphalt mixture, expressed as a weight percentage of the total weight of the bituminous concrete mixture. The units of measurement for the results of the well-known Marshall Flow test noted herein are in one one-hundreths of an inch. For example, if a bituminous concrete test specimen deforms 0.15 inch, the Marshall Flow value is noted as 15.
There have been various prior attempts to eliminate dependence upon petroleum in the manufacture of compacted bituminous concrete or so-called blacktop by using sulfur-extended asphalt compositions. The majority of such teachings require that molten sulfur be utilized in making the sulfur-extended asphalt. However, such prior art liquid sulfur-extended asphalt methods require costly and specialized equipment to maintain the elevated temperature of the molten sulfur (at 246° F. or more) and also to properly blend it with the liquid asphalt cement. In a typical asphalt batch plant, the use of liquid sulfur would require heated liquid sulfur storage tanks, supplemental burners, and associated heated valves, pumps and piping equipment. Additionally, since the molten sulfur and asphalt are preblended before being introduced into the asphalt weigh bucket and finally into the the heated aggregate to form the bituminous concrete, costly high shear energy-type blending units must be used due to liquid sulfur's relatively high viscosity. These include colloid mills, gear pumps, high speed stirrers, propeller mixers, static mixers, or other such devices.
Additionally, the known prior art mix designs for liquid sulfur-extended asphalt typically require that the asphalt be replaced by liquid sulfur on an equal volume basis. This means then that, since sulfur is twice the weight of asphalt, two weight units of sulfur must be included for every asphalt unit being replaced. Such a 2:1 weight ratio replacement was primarily used to minimize the high air void contents found in many sulfur-extended bituminous concrete mixtures of the prior art. Due to the typically prevailing market prices for liquid sulfur and asphalt cement, such prior art liquid sulfur-extended mix designs were not satisfactory from a cost savings standpoint. Thus, they were not widely utilized. The latter is also true because the supply of liquid sulfur has not historically been reliable. Consequently, until the present invention the manufacture of bituminous concrete has remained highly petroleum dependent. Moreover, from an energy consumption standpoint, the extra energy required to maintain molten sulfur at useable liquid states with such prior art mix designs is highly disadvantageous.
There have been prior art attempts to replace liquid asphalt cement by solid sulfur. Such prior art mix designs were also typically produced on an equal volume basis, i.e., a sulfur-to-asphalt weight ratio of 1.75:1, 2:1, or even higher. At such high sulfur concentrations, the resulting pavement product was difficult to compact using conventional rolling techniques. Thus, such prior art designs that were used in relation to highway paving were primarily for repair work. That is, individual segments of asphalt were cast without subsequently being compacted, such as for repairing potholes, for example.
Examples typifying such prior art sulfur-extended asphalt compositions for use in bituminous concrete are disclosed in U.S. Pat. Nos. 2,182,837, 3,738,853, and 3,960,583, British Pat. No. 1,363,706, and Canadian Pat. Nos. 755,999, 945,416 and 1,042,610.
SUMMARY OF THE INVENTION
The present invention overcomes these and other problems of the prior art by providing an improved sulfur-extended asphalt composition for use in making compacted bituminous concrete in which the asphalt cement is replaced by solid sulfur on a 1:1 weight basis and the heat present in the molten asphalt is used to melt the solid sulfur. With the present invention the asphalt comprises less than 3.1% of the total weight of the bituminous concrete mixture. The overall binder content of the bituminous concrete mixture is selectively varied to assure both use of the desired 1:1 replacement ratio and maintenance of proper paving design criteria.
Through use of solid sulfur, preferably in powdered or crushed form, the expensive liquid sulfur handling equipment and high shear energy pre-blending equipment of the prior art mix designs are eliminated. The present invention's replacement of liquid asphalt by solid sulfur on a 1:1 weight basis, rather than the prevailing 2:1 or more weight basis of the prior art mix designs, makes use of sulfur-extended asphalt compositions highly attractive from a cost standpoint. This is because solid sulfur is substantially less expensive than heated liquid sulfur on a delivered-ton basis. Further, the present invention assures that no extra energy is required to heat the solid sulfur since it is melted on-site at the asphalt batch plant by pre-blending it with the heated liquid asphalt directly in the heated asphalt weigh bucket. This is contrary to the prior art liquid sulfur mix designs where the elemental sulfur was first separately melted to a liquid state and then maintained at an elevated temperature, all requiring additional energy. In addition to reduced heat energy consumption, the present invention also provides an economical sulfur-extended asphalt composition by which petroleum dependence is substantially reduced, i.e., almost in half.
A specialized mixing apparatus for use with the conventional heated asphalt cement weigh bucket of a typical asphalt batch plant is also disclosed. This mixing apparatus can be incorporated as an inexpensive modification to an existing asphalt plant or built integrally with new asphalt weigh buckets so as to accommodate the present solid sulfur-extended asphalt process.
Thus, it is a primary object of the present invention to provide a sulfur-extended asphalt composition in which the asphalt is replaced by solid sulfur on a cost-efficient, substantially 1:1 weight basis.
It is another object of the present invention to provide special mixing apparatus for use with a conventional asphalt batch plant to accommodate the blending of solid powdered sulfur with liquid asphalt cement in a heated asphalt weigh bucket.
It is still another object to provide a sulfur-extended asphalt blending process whereby the total energy consumed is substantially reduced from that of conventional methods.
It is a further object to provide a solid sulfur-extended asphalt mix design which eliminates costly liquid sulfur-related equipment required by prior art methods.
It is yet another object to provide a method for making sulfur-extended bituminous concrete whereby a substantially 1:1 sulfur-to-asphalt replacement ratio may be regularly utilized by adjusting the overall binder content.
It is a still further object to reduce harmful sulfur emissions from a sulfur-extended asphalt process.
The means by which the foregoing and other objects of the present invention are accomplished and the manner of their accomplishment will be readily understood from the following specification upon reference to the accompanying drawings, in which:
FIG. 1 is a schematic layout of a typical asphalt batch plant as modified to accommodate the present invention;
FIG. 2 is a front elevation view of the asphalt batch plant shown in FIG. 1;
FIG. 3 is a block diagram of the solid sulfur-related apparatus of the present invention; and
FIG. 4 is a section view of the mixing apparatus of the present invention, taken along lines 4--4 of FIG. 1.
EXAMPLE 1
Preliminarily, it should be understood that a conventional process for making bituminous concrete typically includes the following steps as listed. Asphalt cement is heated to a liquid and maintained at approximately 300° F. A quantity of aggregate in the form of sand, limestone, gravel, or slag is heated to a temperature of approximately 350° F. for a period of time long enough to be completely dried. The dried aggregate is then screened, weighed, and proportioned in a conventional aggregate weigh hopper and mixed with the heated asphalt cement in a blending apparatus such as a pugmill. The resulting bituminous concrete mixture made by such a conventional process generally has a temperature in the range of from 280° F. to 290° F. when leaving the batch plant site. In using this conventional process, the heat energy required to produce one ton of hot mix bituminous concrete is on the order of 350,000 BTU's.
The pavement laying characteristics or so-called "lay down" criteria for a conventional bituminous concrete mix utilizing 100% asphalt cement, i.e., one not extended by sulfur, and listed as Example 1 in the Chart 1 below. As shown there, with an optimum 5% binder content as used in a typical conventional mix and due to the particular aggregate used, and with the binder being 100% asphalt cement, the finished bituminous concrete mix had the following characteristics: a 4.78% air void content, a bulk specific gravity of 2.39, a Marshall Flow of 12.5, and relatively low Marshall Stability rates of 1,400 lbs./in. 2 @ 24 hours and 1,450 lbs./in. 2 @ seven days.
EXAMPLE 2
Further, the usual process for making a typical prior art bituminous concrete mix utilizing liquid sulfur-extended asphalt includes the following steps as listed. The liquid asphalt cement is heated to a temperature of 300° F. and is introduced into a special high shear energy-type preblending unit, such as a colloid mill, for example. At the same time, liquid sulfur maintained at a temperature of at least 280° F. is introduced into the colloid mill through special heat-jacketed delivery lines and blended with the asphalt. This liquid asphalt extension, i.e., replacement, by liquid sulfur is done on essentially an equal volume basis. Thus, two weight units of sulfur are substituted for one weight unit of liquid asphalt cement. Meanwhile, the aggregate is heated and dried to a temperature of approximately 350° F. The total liquid sulfur-extended asphalt blend is proportionately weighed and introduced into the pugmill where the heated aggregate and sulfur-extended asphalt are then mixed.
The final mixture of bituminous concrete made by such a liquid sulfur-extended asphalt process of the prior art is typically at a temperature of 280°-290° F. when leaving the plant site. The heat energy necessary to maintain sulfur in liquid form for subsequent use with liquid asphalt is on the order of 570,920 BTU's per ton of sulfur. This, of course, does not include any heat energy required when the solid sulfur is melted off-site and subsequently transported and stored in heated liquid form at the asphalt batch plant until needed.
The lay down characteristics for such a bituminous concrete mixture utilizing the typical liquid sulfur-extended asphalt technology of the prior art are listed as Example 2 in Chart 1. A test sample was made according to the prior art's equal volume substitution ratio of liquid sulfur to liquid asphalt, i.e., a 2:1 weight ratio substitution. It will be noted that the total sulfur-extended binder content of this test sample was raised to 6.3% which relates to the 5% binder of the conventional mix of Example 1. This is because under existing sulfur-extended asphalt technology, binder content requirements for sulfur-extended asphalt paving are greater than for conventional paving. These higher binder requirements, in turn, result primarily because of the approximately 2:1 weight and specific gravity ratio between the sulfur and asphalt.
More specifically, the Sulphur Development Institute of Canada specifies that the optimum sulfur-extended asphalt binder may be determined from a conventional asphalt cement mix design by using the following formula: ##EQU1## where, (with the values for Example 2 of Chart 1 shown in parenthesis): A=Weight percentage of Asphalt Cement in a Conventional Mix (5.0)
R=Sulfur to Asphalt Binder Ratio (2.0)
S=Weight percentage of Sulfur in the Sulfur-Extended Asphalt Binder (42.0)
G=Specific Gravity of the Asphalt (1.013).
The resulting sulfur-extended binder content for Example 2 then is 6.3%. In any event, the results for such a liquid sulfur-extended mix with a 6.3% binder content are a 2.6% air void content, a 24 hour Marshall Stability rate of 2120 lbs./in. 2 , and a Marshall Flow of 12.5.
DESCRIPTION OF PREFERRED EMBODIMENT
In contrast, the improved sulfur-extended asphalt mix design of the present invention utilizes solid sulfur. The preferred process by which bituminous concrete is made from the present invention includes the following steps. The asphalt cement is heated to a temperature of 300° F. and maintained there. The aggregate is heated and dried at a temperature preferably no greater than 305° F. The purpose for this maximum aggregate drying temperature will be explained later herein. Elemental solid sulfur in bulk form is first pulverized and then introduced in a substantially crushed form into the heated liquid asphalt cement weigh bucket.
The present invention's solid sulfur extension of asphalt cement is accomplished on substantially a 1:1 weight basis, the latter being assured through use of a variable binder content. That is, one weight unit of solid sulfur is added to one weight unit of liquid asphalt cement as weighed in the asphalt weigh bucket. The heat energy present in the liquid asphalt cement held in the asphalt weigh bucket supplies a major part of the heat required to melt the powdered solid sulfur. Only a minor portion of the energy needed for heating of the liquid asphalt, the sulfur, or the mixture of solid sulfur and liquid asphalt is required to be supplied by the heated oil chamber 52 in the asphalt weigh bucket 38.
As the powdered sulfur is introduced into the heated asphalt weigh bucket it is simultaneously mixed with the liquid asphalt and dispersed throughout the same. At this stage, the now completely liquid mixture of heated sulfur and asphalt cement will have a temperature of approximately 270° F. The blended liquid mixture of sulfur and asphalt cement is then introduced into and blended with the heated aggregate in the asphalt batch plant's pugmill. So as to obtain desirable laydown criteria, the binder content (weight percentage of sulfur and asphalt blend) is selected, i.e., varied, so that the asphalt remains less than 3.1% of the total weight of the bituminous concrete mix and so that the desirable 1:1 replacement ratio may be used. The aggregate comprises from 93-95% by weight of the total mix.
The final mixture of bituminous concrete made by the improved process of the present invention will be at a temperature of approximately 280° F. to 285° F. when leaving the plant site. It has been found that bituminous concrete made according to the process of the present invention is no more difficult to compact into pavement than conventional non-extended asphalt mix designs. Contrary to prior art sulfur-extended mix designs, no casting procedures are required with the present invention. Due to the fact that the heated aggregate of the present invention is dried to a lower than usual temperature, the heat energy required to produce one ton of the present invention's bituminous concrete is on the order of only 300,000 BTU's.
Any harmful gases such as H 2 S (hydrogen sulfide) and SO 2 (sulfur dioxide) that may be emitted at the plant site due to the mixing of solid sulfur and liquid asphalt are substantially minimized for two reasons. First, the ambient temperature of the powdered sulfur slightly lowers rather than raises the temperature of the heated asphalt which is held at 300° F. prior to blending. Second, when the lower-temperature blend of liquid sulfur and asphalt is mixed with the higher temperature dried aggregate, the final mix temperature does not rise above that of the aggregate, i.e., approximately 300° F. Thus, at all times the temperature of the resultant bituminous concrete mix is sufficiently below the critical temperature of 309° F., above which H 2 S and SO 2 may be emitted. Accordingly, no harmful emissions other than a slight sulfur odor will result with use of the present invention.
EXAMPLE 3
A sample of bituminous concrete utilizing the solid sulfur-extended asphalt cement process of the present invention is shown as Example 3 in Chart 1. With this test sample, the conventional 5% binder content was maintained as with Example 1. However, the preferred 1:1 sulfur-to-asphalt substitution ratio was utilized. On a weight basis, 42% of the binder content was sulfur, 58% of the binder content was asphalt, while only 2.90% of the total weight of the total bituminous concrete mix was asphalt.
The test sample for this Example 3 was made by first preheating a convection oven to 300° F. and by maintaining this temperature constant throughout the test. A container having a volume of 0.07 ft. was placed in the oven. A quantity of 1.45 lbs. of liquid asphalt was placed in the container and allowed to reach a temperature of 300° F. A quantity of 1.05 lbs. of powdered solid sulfur was added to the heated asphalt cement and mixed into it for one minute by a propeller-type stirrer operated at 1,000 RPM. The sulfur dissolved completely in 30 seconds and mixing and blending were accomplished in one minute. The blended mixture's temperature dropped to 294° F., evidencing that the heat contained in the liquid asphalt cement can be utilized to melt the solid sulfur with only a minor temperature drop. This solid sulfur-extended asphalt blend was then mixed with aggregate heated to 300° F. The resulting bituminous concrete composition of this Example 3 had a 5.5% air void content, a bulk density of 149.1 lbs./ft. 3 , a Marshall Stability rate of 3,510 @ 24 hours, and a Marshall Flow rating of 9.0.
More specifically, it is to be noted that the specific heats of sulfur range from 0.167 BTU's/°F./lb. to 0.250 BTU's/°F./lb., while the specific heats for asphalt, stone, and sand are approximately 0.5, 0.5, and 0.4 BTU's/°F./lb. respectively. (The term "specific heat" as used here is defined as heat in BTU's required to raise the temperature of a material one degree Fahrenheit, per pound of material.) Based upon these specific heats, and if the temperature of the asphalt cement is maintained at 300° F., the final temperature of the liquified solid sulfur-extended asphalt cement blend in bulk quantities will have a temperature of approximately 270° F. when ready to be introduced into the heated aggregate. Thus, when mixed with the aggregate heated to 305° F., the temperature for the resultant bituminous concrete mix as it is ready to leave the plant site will be on the order of 280° F. to 285° F. In view of the above, no additional energy source is required to melt the solid sulfur when using the improved process of the present invention.
CHART #1__________________________________________________________________________ExampleSulphur %- Substitution Binder Sulphur-Asphalt 24 Hour MarshallNo. Asphalt % Ratio Content (as % of total mix) % Air Voids Bulk Density Stability Marshall__________________________________________________________________________ Flow1 0-100 N.A. 5.0 0-5.0 4.78 148.6 1400 12.52 42-58 2:1 6.3 2.65-3.65 2.60 152.8 2120 12.53 42-58 1:1 5.0 2.10-2.90 5.5 148.0 3510 9.04 45-55 1:1 5.4 2.43-2.97 4.8 149.1 2660 10.0__________________________________________________________________________
EXAMPLE 4
A second sample made according to the present invention is depicted as Example 4 in Chart 1. In this case, the binder content was raised from 5% as with previous Examples 1 and 3 to 5.4%. Again the 1:1 sulfur-to-asphalt substitution ratio was used. This heavier binder content on a weight basis comprised 45% sulfur and 55% asphalt cement. In this instance the asphalt was only 2.97% by weight of the total bituminous concrete mix. Utilizing the same test procedures and equipment as explained in relation to Example 3 above, the resulting bituminous concrete composition had a 4.8% air void content, a bulk density of 149.1 lbs./ft. 3 , a 24 hour Marshall Stability rate of 2660 lbs./in. 2 , and a Marshall Flow rating of 10.0.
It will be understood that, for the four Examples described above, the following aggregate comprising a conventional CA-16 crushed limestone surface mixture was used:
______________________________________ % Specifi- cations* % Passing Retained of Exam- Specifications*Item Through By ples 1-3 For Example 4______________________________________Crushed Lime-stone Rock 1/2" #10 sieve 60.3% 60.3%Coarse Sand #10 sieve #80 sieve 20.5% 20.5% #200Fine Sand #80 sieve sieve 11.0% 11.0% minus #200Mineral Filler sieve 3.2% 2.8%Binder Content 5.0% 5.4% 100.0% 100.0%______________________________________ *Percentage of total bituminous concrete mix by weight.
Also, an AC-10 asphalt cement from Shell Oil Company was used throughout.
Other test specimens and their test results using the solid sulfur-extended process of the present invention and having varying binder contents are shown as Examples 5 through 10 in Chart 2 below. It will be understood that any increase in binder content and hence weight of the respective binder content and hence weight of the respective binder was compensated for by reducing the weight percentage of the coarse sand or mineral filler in the aggregate.
CHART 2__________________________________________________________________________ExampleSulphur %- Substitution Binder Sulphur-Asphalt 24 Hour MarshallNo. Asphalt % Ratio Content (as % of total mix) % Air Voids Bulk Density Stability Marshall__________________________________________________________________________ Flow5 42-58 1:1 5.20 2.18-3.01 5.0 148.8 1260 6.06 42-58 1:1 5.20 2.18-3.01 4.4 149.6 2413 6.57 42-58 1:1 5.20 2.18-3.02 5.60 147.8 2340 6.78 42-58 1:1 5.20 2.18-3.02 5.5 151.7 2180 9.09 45-55 1:1 5.20 2.34-2.86 5.8 147.5 2580 7.010 45-55 1:1 5.60 2.52-3.08 5.7 147.7 2340 10.0__________________________________________________________________________
As can be seen from Charts 1 and 2, solid sulfur-extended asphalt mix designs made according to the present invention exhibit similar properties as compared to both conventional (100% asphalt) and liquid sulfur-extended mix designs. In fact, in some instances, these solid sulfur-extended mixes are even superior. Accordingly, depending upon the specific lay down characteristics as dictated by field conditions, the air void content and bulk density of a particular mix design are believed to be a function of the amount of binder content in a bituminous concrete mix. It will be understood that with an optimum paving mix, the bulk denisty is preferably within the range from 147-155 lbs./ft/ 3 , and the air void content is preferably no greater than 5.8%. Where a heavier binder content (greater than the conventional 5%) is required with the present invention to accommodate particular road design criteria, the present solid sulfur-extended asphalt mix may still be satisfactorily used such that asphalt can be replaced with sulfur on substantially a 1:1 weight basis. Further, the asphalt is typically less than 3.1% by weight of the total bituminous concrete mix. Thus, by selectively varying the binder content as required and by assuring that the compaction of the bituminous concrete into pavement is accomplished within the conventional temperature range, i.e., 240° F. to 265° F., a satisfactory pavement product can be economically produced according to the present invention.
It is thus apparent that use of the present invention can result in savings of the amount of purchased liquid asphalt of up to 45 percent, yet without any increase in heat energy consumption beyond that required for a conventional bituminous concrete mix. In fact, due to the fact that the aggregate in the present invention is dried at a lower temperature, the total energy utilized for finished product on a per-ton basis is somewhat less than that for a conventional mix. Also, the present invention overcomes the high cost of energy inherent in prior art liquid sulfur-extended asphalt mix designs by avoiding the extra energy needed to melt, transfer, blend, or store the liquid sulfur.
Turning now to a description of the apparatus necessary to perform the process of the present invention, there is shown in FIG. 1 a schematic-type plan view of the well-known asphalt batch plant, generally denoted by reference numeral 20. The asphalt plant 20 includes aggregate stockpiles 22, an aggregate feed mechanism 24, an aggregate dryer 26 having a combustion chamber (not shown), a heated asphalt storage tank 28 having supplemental burners (not shown), a tower support structure 30, a pugmill apparatus 32 mounted on the tower 30 and used to mix the various constituent materials, a silo 34 for storing mineral filler, a hot elevator mechanism 36 for transferring the dried aggregate from the dryer to a series of screens 37 which size it, an aggregate weigh hopper 39 for weighing the sized and heated aggregate, and a heated asphalt weigh bucket 38 supported off the tower 30 by scales (not shown) adjacent the pugmill 32. The batch plant 20 also includes a solid sulfur bulk storage bin 40 and a screw auger or vane feeder type mechanism 42. The auger 42 is utilized to transfer the solid sulfur from a sulfur crusher device 50 to the asphalt weigh bucket 38. The asphalt plant's usual pollution control mechanism, such as a bag collector, for example, has been omitted in FIGS. 1 and 2 for purposes of better viewing.
As best seen in FIG. 2, the tower 30 also includes elevated aggregate storage containers 44 which transfer sized, heated aggregate into the aggregate weigh hopper 39. The asphalt storage tank 28 has a pump 46 for transferring liquid asphalt 29 from tank 28 through a delivery line 48 into the asphalt weigh bucket 38. Since the asphalt weigh bucket 38 is connected to a scale (not shown) in a wellknown manner, it is capable of weighing any ingredients placed therein. In this manner, the scale-connected asphalt weigh bucket 38 can be used to proportion and mix the solid sulfur 41 and the liquid asphalt 29. It will be understood that both the aggregate weigh hopper 39 and asphalt weigh bucket 38 feed into the pugmill 32.
As seen in FIG. 4, the asphalt weigh bucket 38 is hot-oil jacketed in a well-known manner. That is, it is surrounded by heated oil chambers 52 which maintain the desired temperature within the asphalt weigh bucket 38, preferably at 300° F. with the present invention. The sulfur feeder 42 and asphalt delivery line 48 are respectively connected to the top cover panel 49 of the weigh bucket 38. The latter is outfitted with a special mixing apparatus, generally denoted by reference numeral 54. This mixing apparatus 54 includes a shaft 56 which is journalled within bearings 58 on each end wall of bucket 38. The shaft 56 is rotatably driven by a motor 60 mounted exteriorly of the weigh bucket 38. A series of paddle members 62 are mounted along the shaft 56. A plurality of paddle holes 64 are formed on the paddles 62 to effect the proper mixing action within the weigh bucket 38 when the paddle shaft 56 is rotated by motor 60.
FIG. 3 depicts in block diagram form the special equipment needed then to modify an existing asphalt batch plant, such as that of FIGS. 1 and 2, so as to accommodate the solid sulfur-extended asphalt process of the present invention. As shown there, the liquid asphalt 29 is pumped from the asphalt storage tank 28 by a pump 46 into the plant's heated asphalt weigh bucket 38. There, due to the hot-oil jacket heating of the weigh bucket 38, the liquid asphalt 29 is brought up to a temperature of approximately 300° F. Further, solid sulfur 41 from the sulfur storage bin 40 is first pulverized by the crusher 50 and then transported by the auger feeder 42 into the plant's asphalt weigh bucket 38. Operation of the mixing apparatus 54 within the weigh bucket 38 causes the crushed solid sulfur to be quickly melted and uniformly dispersed throughout the liquid asphalt. A uniform blend of sulfur-extended asphalt is then obtained. This blend of sulfur-extended asphalt is then placed into the pugmill 32. In a well known fashion, the aggregate weigh hopper 39 is similarly filled with appropriate amounts of the various aggregate materials. These materials are each proportioned, weighed, and then placed into the pugmill 32. After mixing all ingredients in the pugmill, the finished solid sulfur-extended asphalt mix is delivered to the laydown site and compacted into pavement.
It will be understood that, in relation to FIG. 4, the preferred embodiment of mixing apparatus 54 (stirrer mechanism comprising shaft 56, motor 60, and paddles 62) can be replaced by any other well-known type of mixing apparatus. The only requirement is that some form of mixing action occur within the heated asphalt weigh bucket 38 so as to promote melting and pre-blending of the solid sulfur within the asphalt prior to mixing with heated aggregate in the pugmill 32. Further, it will be understood that conventional heated weigh buckets of existing asphalt batch plants can be readily retrofitted with the mixing apparatus 54 and auger feeder mechanism 42.
From the foregoing, it is believed that those skilled in the art will readily appreciate the unique features and advantages of the present invention over previous bituminous concrete compositions made with sulfur-extended asphalt and the methods and apparatus for making the same. Further, it is to be understood that while the present invention has been described in relation to a particular preferred embodiment as set forth in the accompanying drawings and as above described, the same nevertheless is susceptible to change, variation and substitution of equivalents without departure from the spirit and scope of this invention. It is therefore intended that the present invention be unrestricted by the foregoing description and drawings, except as may appear in the following appended claims. | An improved sulfur-extended asphalt composition and method for use in making compacted bituminous concrete, whereby solid sulfur, preferably in powdered form, is added to liquid asphalt on substantially a 1:1 weight basis, the asphalt comprising less than 3.1% of the weight of the total bituminous concrete mixture. The solid sulfur is melted by the heat present in the molten asphalt thereby lessening the overall energy consumption and eliminating the need for any liquid sulfur-related heating equipment. The overall binder content of the resultant bituminous concrete is varied so as to both maintain the 1:1 sulfur-replacement-of-asphalt relationship utilized with this invention, and to reduce the occurrence of air voids. Such a 1:1 replacement relationship provides economic efficiencies in bituminous concrete production not previously obtainable. The resultant sulfur-extended bituminous concrete when compacted provides substantially increased mechanical strengths over conventional asphalt mix designs. A solid sulfur mixing and blending apparatus is disclosed for use with asphalt batch plants to accommodate the present sulfur-extended asphalt composition and method. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the filing benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 60/998,809, filed on Oct. 15, 2007, the entire teachings of which are incorporated herein by reference.
[0002] Related to patent application Ser. No. 11/799,011, filed May 1, 2007
[0003] Related to patent application Ser. No. 11/796,920, filed May 1, 2007
TECHNICAL FIELD
[0004] The present invention relates to a computer designed to be mounted on a bag front for mobile use.
BACKGROUND OF THE INVENTION
[0005] Bag computers are a combination of a bag, computer and display such that the bag wearer/operator can pivot the display into his line of sight for use. Manual controls are also included on the outside of the bag so that the operator can use the computer on short notice in any situation without unloading it or setting it up for use.
[0006] Because it is used vertically and in the mobile environment, it may be used and physically improved in ways not needed for other portable computers such as lap tops or handhelds.
[0007] For example, a bag computer user might want the option to have the display panel hold its position for viewing without using the hands or have the display panel swing freely so it may automatically fall flat against the bag front and out of the way when not held so as to not interfere with other tasks the operator might have.
[0008] Because the hinge might be the only part of the computer body on the outside of the bag, it is the most reasonable venue for mounting speakers, a heat dissipation duct outlet or a line of sight infrared antenna.
[0009] Because of the stabilizing effect of the bag and the bag strap, the bag may be “balanced” in the lap while seated, with or without using the hands, to improve viewing qualities if the hinge is constructed to pivot 180 degrees from its stored position against the bag front.
[0010] These hinge improvements apply to bag computers which were described in U.S. application Ser. Nos. 11/796,920, 11/799,011, 11/163,763 and 11/001,428.
BRIEF DESCRIPTION OF THE INVENTION
[0011] The bag computer multi function hinge is meant to improve the operation of bag computers. Bag computers include a display pivotally mounted to the outside front of a matching bag. The hinge for the display thus may become a venue for improving the bag computer's quality.
[0012] The hinge may be configured to allow the display to either move with restrain or locking so that the operators may view the display without holding it.
[0013] Alternatively, the operator may want the display to move without restrains so that it may fall flat against the bag front and out of the way when not held. The restrain may be caused by friction between the display hinge members and the bag hinge members or by friction between a brake on one hinge member and the axle fixed to the other hinge member. A switch, button or dial allows the operator to quickly make the change.
[0014] The hinge may be a venue for mounting speakers. One or more speakers may be mounted within an inside mounted computer body with a tunnel and opening leading to the outside surface of the hinge. Instead, speakers may be mounted directly to the hinge.
[0015] The hinge may be a venue for the outlet of a heat dissipation duct leading from inside the computer body. The duct may be combined with a speaker tunnel to form a single outlet.
[0016] The hinge may be a venue for an infrared antenna. Because of the hinge's location outside the bag, a line of sight antenna connected directly to the computer body may be used.
[0017] The hinge may be configured to swing 180 degrees so that the display is facing an operator in back of the bag. In the sitting position with the bag in the operator's lap and the bag's strap support the upper part of the bag, the operator can view the display more easily.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0018] FIG. 1 This is a bag computer with the hinge attached to the bag front and separate computer inside.
[0019] FIG. 2A This is a bag computer with the hinge attached to the bag front, separate computer inside and the display removed
[0020] FIG. 2B This shows the display with one possible attachments means to match the bag.
[0021] FIG. 3 This is a computer with body and display hinged together and computer to bag coupling.
[0022] FIG. 4 This is a computer with body and display hinged together made to mounting in an outside holster.
[0023] FIG. 5 This is a computer with body and display hinged together with attachments to match a docking port of the bag's outside front wall.
[0024] FIG. 6 This is a computer with body and display hinged together with a coupling to match the top wall of the bag.
[0025] FIG. 7 This is a computer with body and display hinged together with the display facing the body when closed. Included is a computer to bag coupling and attachments to match the bag.
[0026] FIG. 8 This is a computer with body and display hinged together with the display facing the body when closed. Included are attachments to match the bag.
[0027] FIG. 9 Shown are views of the multi function hinge with the friction disengagements function (engaged and disengaged).
[0028] FIG. 10 This is a magnification of the hinge disengagement mechanism with friction between the display and body half hinges.
[0029] FIG. 11 Shown are views of the multi function hinge with the friction disengagements function (engaged and disengaged).
[0030] FIG. 12 This is a magnification of the hinge disengagement mechanism with friction between the body half hinge and axle.
[0031] FIG. 13 This is a computer for bag mounting with body and display hinged together and speaker in the hinge.
[0032] FIG. 14A This is the multi function hinge with a speaker in the hinge using a tunnel from a speaker mounted inside of the computer body.
[0033] FIG. 14B This is a magnified cross section of the hinge speaker using a tunnel from a speaker inside the computer body.
[0034] FIG. 15A This is the multi function hinge with a speaker in the hinge using a speaker mounted directly to the hinge extension of the computer body.
[0035] FIG. 15B This is a magnified cross section of the hinge speaker mounted directly to the hinge extension of the computer body.
[0036] FIG. 16 This is a bag computer with the hinge attached to the bag front, separate computer inside and the display removed. A speaker is mounted facing up on the display half hinge.
[0037] FIG. 17A This is a cross section of a bag computer, with bag, using a hinge attached to the bag front and separate computer inside (display not shown). The speaker, inside the computer body, has a sound tunnel which matched a sound tunnel is the bags computer to bag coupling.
[0038] FIG. 17B This is a magnified view of a cross section of a bag computer using a hinge attached to the bag front and separate computer inside (display not shown). The speaker, inside the computer body, has a sound tunnel which matched a sound tunnel is the bags computer to bag coupling.
[0039] FIG. 18A This is a cross section of a bag computer, with bag, using a hinge attached to the bag front (inside computer and display not shown). It shows the computer to bag coupling with opening and sound tunnel that match the computer.
[0040] FIG. 18B This is a magnified view of a cross section of a bag computer using a hinge attached to the bag front (inside computer and display not shown). It shows the computer to bag coupling with opening and sound tunnel that match the computer.
[0041] FIG. 19 This is a computer for bag mounting with body and display hinged together and heat dissipation duct outlet in the hinge.
[0042] FIG. 20A This is a cross section of a computer with multi function hinge and heat dissipation duct outlet. Shown is the duct passing through the computer body to the hinge outlet.
[0043] FIG. 20B This is a magnified view of a cross section showing the heat dissipation duct leading out through the computer body hinge extension.
[0044] FIG. 21A This is a view of a bag computer with its display panel pivoted flat against the bag front.
[0045] FIG. 21B This is a view of a bag computer with its display panel pivoted perpendicular to the bag front and in the line of sight of the operator.
[0046] FIG. 21C This is a view of a bag computer with its display panel pivoted up above and parallel to the bag front for viewing from in back of the bag.
[0047] FIG. 22 This figure shows the method for holding the bag computer in the lap and viewing the display from in back of the bag.
[0048] FIG. 23 This figure shows the method for holding the computer in FIG. 22 can also be used for typing.
[0049] FIG. 24 This figure shown an operator viewing and using a bag computer held flat in his lap.
[0050] FIG. 25 This figure shows the operator prone while holding the bag computer on his stomach and viewing the display from in back of the bag.
DETAILED DESCRIPTION OF THE INVENTION
[0051] The multi function hinge for bag computers is special for bag computers and improves their performance. As explained below, they provide functions that are not needed in computers not meant for the bag front venue.
[0052] Bag computers, FIG. 1 , for example, are a bag 1 and computer combination designed so that, when assembled, the computer's display panel 3 can pivot from a vertical position along the outside of the bag front wall 4 to position with the display facing and in the line of sight of the operator/wearer. Manual controls and computing unit are also included. Bag computers include an interior space for carrying general cargo.
[0053] In all cases, the display panel must pivot on the bag front and this pivoting may be accomplished with a display panel to bag front hinge which may be multi functional. Bag computers with removable displays may have components arranged is several ways. Hence, the multi function hinge may be located in a number of different bag computer component venues.
[0054] As shown in FIG. 2 , the hinge 49 may be located on the bag front 4 where a removable display panel 3 attaches to it with matching attachments 50 . The computing unit may be located inside the bag or in the display panel.
[0055] Alternatively, shown in FIG. 3 , the hinge 49 may be located between the body 2 and display 3 panels of a computer specially adapted to mount on the inside surface, outside surface or be a part of the bag's front wall.
[0056] The body panel has a front surface nearest the display when closed, an opposite back surface, a bottom edge, top edge and two side edges. The display panel attaches with a hinge means with its display facing toward or away front the bodies front surface depending on the particular computer configuration.
[0057] Such a specialized computer, as shown in FIG. 3 , may have its computer body 2 mounted inside the front bag wall with an inside mounting structure and the display panel 3 protruding out the front bag wall through an opening. Its display 9 may face out on the display panel 3 when shut. It would have a size, shape and fitting, such as physical and electrical connections 52 , hinge extension 10 and/or computer to bag coupling 51 , to match the bag that holds it.
[0058] As shown in FIG. 4 , the computer with its display 9 facing out on the display panel 3 when shut may instead be mounted in a holster on the outside front surface of the bag with body 2 shape, attachments, hinge extension 10 and fittings to match the bag.
[0059] Alternatively, as shown in FIG. 5 , a computer with its display 9 facing out on the display panel 3 when shut may be mounted on the outside of the front bag wall using body 2 attachments 50 which match a docking port on the bag's outside front.
[0060] In another venue for the multi function hinge 49 for bag computers, shown in FIG. 6 , the computer with its display 9 facing out on the display panel 3 when shut may be installed through an installation opening in the bag's top wall. An inside mounting structure for the body may be on the inside of the bag's front wall. The display panel 3 has a hinge extension to allow it to pivot shut over the bag's outside front. This computer would have a size, body 2 shape and fittings, such as physical and electrical connections, hinge extension 10 and/or bag to computer coupling 51 , to match the bag that holds it.
[0061] Shown in FIG. 7 , the computer may have its display 9 facing inward on the display panel 3 while shut and be installed to a mounting structure on the front wall inside surface with the display panel projecting through an opening in the bag's front wall. This computer would include body 2 size and shape, fittings, such as attachments 50 , hinge extension 10 and/or bag to computer coupling 51 , to match the bag that holds it.
[0062] Shown in FIG. 8 , the computer may have its display 9 facing inward on the display panel 3 while shut and be installed to a mounting structure on the front wall outside surface. This computer would include fittings, such as attachments 50 to match the bag that holds it.
[0063] The bag computer may be seen as a system using a collection of components which, when assembled, result in a unit with one utility. It is anticipated that there may be other means of mounting a computer to a bag's front wall to produce a bag computer's operating characteristics. The bag computer multi function hinge utility is equally applicable to bag computers produced by any of these means.
[0064] The first function of the multi function hinge for bag computers, to be used separately or in combination with other functions, is a position holdings hinge disengagement mechanism allowing a quick switch between an angular position holding display panel to a free swinging display panel. While operating a bag computer, the operator might want to have the option to have the display hinge either 1) hold its angular position so that the display can be viewed without holding the display panel, or 2) have the display panel free swinging so that the panel may fall flat against the bag front when not held. In this way, the display panel will not interfere with other tasks the operator might have in front of him. The position holding mechanism may either allow forced movement or lock the display in a position. The hinge may consist of a “half hinge” on the display panel matching and fitting to a “half hinge” on the computer/body panel or bag front. A separate axle may be employed to connect the two.
[0065] FIG. 9 shows one embodiment of a position holding hinge means with disengagement mechanism. The hinge may consist of two or more half hinges, 40 and 41 , some on the display panel and others on the computer's body panel or bag front. By actuating the disengagement mechanism 42 , the hinge's position holding quality may be engaged 43 or disengaged 44 .
[0066] FIG. 10 shows, in magnification, that the position holding mechanism may be a movable disk surface 11 on one of the half hinges (display or body) which matches and engages a stationary disk surface 12 on the opposing half hinge to produce the friction needed to hold the hinge angle. The disk contact surfaces may have friction or ratchet/pawl surfaces. The disk surfaces may be shaped as, for example, a dome or cone or other shape to improve friction characteristics. The movable friction surface may move parallel to the axle 13 but is keyed to the half hinge housing 17 so that it cannot rotate around the axel. A spring 16 or elastic cushion may be included to maintain steady pressure even if wear occurs.
[0067] The hinge has a disengagement mechanism to allow the hinge to swing freely. The movable friction surface may be disengaged from the stationary friction surface with a disengagement screw 14 , button, lever or other device capable of moving the fiction disk along the axle axis. In the pictured case, the engagement screw engages/disengages the friction surfaces by sliding the movable disk surface parallel to the axle with a twisting handle 15 on the end of the hinge.
[0068] In addition, there may be an angular resistance adjustor such as a separate threading/screw 18 to move the entire engagement/friction surface assemble in or out of the hinge housing along the axle axis to modify the amount of friction when the friction surfaces are engaged.
[0069] FIG. 11 shows an alternative embodiment of a position holding hinge means with disengagement mechanism. The hinge may consist of two or more half hinges, 40 and 41 , some on the display panel and others on the computer/body panel or bag front. By actuating the disengagement mechanism, the hinge's position holding quality may be engages 43 or disengaged 44 .
[0070] The position holding hinge may, as shown magnified in FIG. 12 , consist of a brake 19 which uses a friction surface or ratchet/pawl to engage the hinge's axle 13 and acts as a brake. The axle is keyed into one half hinge (display or body) 20 so it cannot move relative to that part. The brake is located on and attached to the opposing half hinge housing 17 with guides, lever arm 23 or other holder that fixes its position relative to that housing while allowing movement for engagement.
[0071] The brake may be engaged/disengaged using a disengagement mechanism such as a sliding wedge 22 , screw, cam, button or other means of applying pressure to the brake. The disengagement mechanism may be accessible from the outside of the hinge housing.
[0072] The disengagement mechanism may be adjustable so that the friction on the axle may be varied. The brake may have a spring or elastic cushion included to maintain steady pressure even if wear occurs.
[0073] Because the free swinging display may hit hard against the computer body or bag front, there may be included on the computer body or bag front a shock absorber such as a rubber cushion or other suitable absorbing material.
[0074] In another function of the multi function bag computer hinge, to be used separately or in combination with other functions, the hinge may be a venue for computer sound. If the computer is mounted inside the bag with the display protruding out through an opening to the outside front of the bag or if the hinge is part of the bag with a separate computer body mounted inside the bag, the hinge is the most reasonable place to put the computer sound device. Independent sound openings in the bag are not needed.
[0075] As shown in FIG. 13 , if the computer is meant to mount on the inside of a bag with its display protruding out through an opening in the bag front or in a holster on the bag front, the hinge means 6 between the body 2 and display panel 3 has an extension 10 out from the body so that the display can shut with the bag material between the body and display.
[0076] In one embodiment, FIG. 14A and FIG. 14B , the speaker 24 is mounted inside the computing unit body. Extending from the audio outlet 25 of the speaker through the body and stationary half hinge portion of the hinge extension 10 and out a sound outlet in its top and facing up is a sound tunnel 26 to carry the sound. The speaker outlet may be larger than the tunnel outlet allowing a larger speaker. The tunnel outlet may be covered with a grill, sound permeable membrane or other protection. There may be one or more speakers, tunnels and outlets.
[0077] As shown in FIG. 15A and FIG. 15B , the speaker may, alternatively, be mounted directly on or embedded into the hinge extension 10 upper surface with its audio outlet 25 directed upward. The speaker driver 27 may be located in the hinge extension and attached to a membrane 28 serving the purpose of a speaker cone and speaker protection as well as directing the sound upward to the operator.
[0078] Alternatively, the speaker mounted to the hinge extension may be a flat acoustic panel attached to the upper surface. There may be more than one speaker mounted on the hinge extension.
[0079] In either of these arrangements, the speaker may extend from the hinge extension onto the top edge of the computer body as in the case where the computer is mounted in a pocket and the entire top of the computer is exposed.
[0080] Shown in FIG. 16 , if the display to bag front hinge 41 is part of the bag 1 with the computing unit in a separate body mounted inside the bag, the hinge may have a sound tunnel to carry sound from a speaker in the body to a sound outlet 57 in the top of the hinge extension where it faces up toward the operator. Shown in FIG. 17A and magnified in FIG. 17B , the inside computer 2 is mounted to the inside of the front wall with a mounting structure such as a footing 53 and flap 54 , so that a sound tunnel 55 in the body leads from the speaker 24 to an outlet in the body which aligns with the bag's coupling 51 and a continuation of the sound tunnel 26 in the coupling which carrying the sound through the hinge and to the sound outlet in its top. FIG. 18A and magnified in FIG. 18B show the bag without the computer mounted. The coupling with the inside 56 and outside 57 openings can be seen.
[0081] Alternatively, a display to bag front hinge as part of the bag with a separate computer body mounted inside the bag may have the speaker mounted to the upper surface of the hinge extension, as described above.
[0082] In another function of the multi function bag computer hinge, to be used separately or in combination with other functions, the hinge may be a venue computing unit heat dissipation duct outlet.
[0083] If the computer is mounted inside the bag with the display protruding out through an opening to the outside front of the bag or if the hinge is part of the bag with a separate computer body mounted inside the bag, the hinge is the most reasonable place to put the heat dissipation duct.
[0084] In computers with a display panel 3 and a body panel 2 hinged 6 together, shown in FIG. 19 , FIG. 20A and magnified in FIG. 20B , the inside mounted computer body may have one or more heat dissipation ducts 58 to carry heat away from internal components and/or heat sinks. These ducts may have an inlet 59 near the bottom of the computer body and lead past hot electrical elements in the computing unit and through the hinge extension 10 and through a computer heat dissipation outlet 60 to the outside of the computer. The heat dissipation system may employ passive draft or may include a fan driven by the memory disk drive or other motor.
[0085] Heat dissipation ducts may be used instead with a display to bag front hinge that is part of the bag. In this case, a separate computer body is mounted on the inside the bag's front wall with a mounting structure. The heat duct outlet in the body aligns with a continuation of the heat duct in the bag's coupling which carries the heat to the computing unit heat dissipation outlet in the top of the hinge.
[0086] These heat dissipation outlets and ducts are similar to the sound tunnels described above and may be combined with the sound tunnels coming front internally mounted speakers.
[0087] In another function of the multi function bag computer hinge, to be used separately or in combination with other functions, the hinge may be a venue for an antenna.
[0088] The display to bag front hinge may act as a mounting place for one or more antennas so that the computer may communicate with other components on the bag or with external equipment without direct wiring. Antennas, such as radio frequency or infrared, may be mounted inside the hinge or on the surface of the hinge. For example, an infrared antenna may be mounted to the lower surface of the hinge and directed toward a keyboard or other input/output device mounted lower down on the bag's front surface. An infrared antenna may instead be mounted facing forward to communicate with external receivers.
[0089] In another function of the multi function bag computer hinge, to be used separately or in combination with other functions, the hinge a means and method of improving the visibility of the display by pivoting it about 180 degrees from its storage position.
[0090] As shown in FIGS. 21A , 21 B and 21 C, if the display panel 3 is allowed to swing about 180 degrees 46 from the stored position, the display 9 will be facing backward toward the operator's body and viewable over the top of the bag. When the operator is sitting, FIG. 22 , the bottom wall of the bag 47 may be supported by the operator's lap and the upper end of the bag may be supported by the shoulder strap 48 of the bag so that it remains in a more upright position. In this way, the display 9 is more directly in front of the operator. FIG. 23 shows that typing is possible in this position. This position may also be used when the operator is standing or prone, FIG. 24 . As an option to viewing the display while the bag is resting on its back in the operator's lap, FIG. 25 , this position moves the display away from the operator's body and may reduce neck strain.
[0091] Improvements to the bag's hinge include 1) positioning the hinge as near as possible to or at the corner between the front surface and top edge of the bag and computer, 2) including a hinge stop on the bag and/or computer to reinforce and hold the display panel to a maximum 180 degree position, 3) including a lock on the hinge to lock the display panel into the 180 degree position. | Disclosed is a multi function hinge for bag computers which may include one or more of five functions to improve the operation of a bag computer. The functions include 1) a hinge which can alternate between holding the display at any angle and allowing the display to pivot freely without restraint, 2) speakers mounted to the hinge so that sound can be heard outside the bag without sound openings in the bag, 3) a heat dissipation outlet to allow cooling of an inside mounted computer, 4) an infrared antenna mounted on the hinge for communicating with other bag computer components or outside receivers/sources, 5) a hinge capability of pivoting 180 degrees for viewing from behind the bag. | 0 |
RELATED APPLICATIONS
This application is related to U.S. application Ser. No.: 08/942,402, entitled, “DIAGNOSTIC AND MANAGING DISTRIBUTED PROCESSOR SYSTEM”, U.S. application Ser. No. 08/942,222, entitled “SYSTEM FOR MAPPING ENVIRONMENTAL RESOURCES TO MEMORY FOR PROGRAM ACCESS”, and U.S. application Ser. No. 08/942,214, entitled “METHOD FOR MAPPING ENVIRONMENTAL RESOURCES TO MEMORY FOR PROGRAM ACCESS”, which are being filed concurrently herewith on Oct. 1, 1997.
PRIORITY CLAIM
The benefit under 35 U.S.C. § 119(e) of the following U.S. provisional application(s) is hereby claimed:
Application
Filing
Title
No.
Date
“Remote Access and Control of Enviromental
60/046,397
May 13,
Management System”
1997
“Hardware and Software Architecture for
60/047,016
May 13,
Inter-Connecting an Environmental
1997
Management System with a Remote Interface”
“Self Management Protocol for a Fly-By-Wire
60/046,416
May 13,
Service Processor”
1997
“Computer System Hardware Infrastructure for
60/046,398
May 13,
Hot Plugging Single and Multi-Function PC
1997
Cards Without Embedded Bridges”
“Computer System Hardware Infrastructure for
60/046,312
May 13,
Hot Plugging Multi-Function PCI Cards With
1997
Embedded Bridges”
APPENDICES
Appendix A, which forms a part of this disclosure, is a list of commonly owned copending U.S. patent applications. Each one of the applications listed in Appendix A is hereby incorporated herein in its entirety by reference thereto.
COPYRIGHT RIGHTS
A portion of the disclosure of this patent document contains material which is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the: Patent and Trademark Office patent files or records, but otherwise reserves all copyright rights whatsoever.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the field of fault tolerant computer systems. More particularly, the invention relates to a managing and diagnostic system for evaluating and controlling the environmental conditions of a fault tolerant computer system.
2. Description of the Related Technology
As enterprise-class servers become more powerful and more capable, they are also becoming ever more sophisticated and complex. For many companies, these changes lead to concerns over server reliability and manageability, particularly in light of the increasingly critical role of server-based applications. While in the past many systems administrators were comfortable with all of the various components that made up a standards-based network server, today's generation of servers can appear as an incomprehensible, unmanageable black box. Without visibility into the underlying behavior of the system, the administrator must “fly blind.” Too often, the only indicators the network manager has on the relative health of a particular server is whether or not it is running.
It is well-acknowledged that there is a lack of reliability and availability of most standards-based servers. Server downtime, resulting either from hardware or software faults or from regular maintenance, continues to be a significant problem. By one estimate, the cost of downtime in mission critical environments has risen to an annual total of $4.0 billion for U.S. businesses, with the average downtime event resulting in a $140 thousand loss in the retail industry and a $450 thousand loss in the securities industry. It has been reported that companies lose as much as $250 thousand in employee productivity for every 1% of computer downtime. With emerging Internet, intranet and collaborative applications taking on more essential business roles every day, the cost of network server downtime will continue to spiral upward. Another major cost is of system downtime administrators to diagnose and fix the system. Corporations are looking for systems which do not require real time service upon a system component failure.
While hardware fault tolerance is an important element of an overall high availability architecture, it is only one piece of the puzzle. Studies show that a significant percentage of network server downtime is caused by transient faults in the I/O subsystem. Transient failures are those which make a server unusable, but which disappear when the server is restarted, leaving no information which points to a failing component. These faults may be due, for example, to the device driver, the adapter card firmware, or hardware which does not properly handle concurrent errors, and Often causes servers to crash or hang. The result is hours of downtime per failure, while a system administrator discovers the failure, takes some action and manually reboots the server. In many cases, data volumes on hard disk drives become corrupt and must be repaired when the volume is mounted. A dismount-and-mount cycle may result from the lack of hot pluggability in current standards-based servers. Diagnosing intermittent errors can be a frustrating and time-consuming process. For a system to deliver consistently high availability, it should be resilient to these types of faults.
Modern fault tolerant systems have the functionality to monitor the ambient temperature of a storage device enclosure and the operational status of other components such the cooling fans and power supply. However, a limitation of these server systems is that they do not contain self-managing processes to correct malfunctions. Thus, if a malfunction occurs in a typical server, the one corrective measure taken by the server is to give notification of the error causing event via a computer monitor to the system administrator. If the system error caused the system to stop running, the system administrator might never know the source of the error. Traditional systems are lacking in detail and sophistication when notifying system administrators of system malfunctions. System administrators are in need of a graphical user interface for monitoring the health of a network of servers. Administrators need a simple point-and-click interface to evaluate the health of each server in the network. In addition, existing fault tolerant servers rely upon operating system maintained logs for error recording. These systems are not capable of maintaining information when the operating system is inoperable due to a system malfunction.
Existing systems also do not have an interface to control the changing or addition of an adapter. Since any user on a network could be using a particular device on the server, system administrators need a software application that will control the flow of communications to a device before, during, and after a hot plug operation on an adapter.
Also, in the typical fault tolerant computer system, the control logic for the diagnostic system is associated with a particular processor. Thus, if the environmental control processor malfunctioned, then all diagnostic activity on the computer would cease. In traditional systems, there is no monitoring of fans, and no means to make up cooling capacity lost when a fan fails. Some systems provide a processor located on a plug-in PCI card which can monitor some internal systems, and control turning power on and off. If this card fails, obtaining information about the system, and controlling it remotely, is no longer possible. Further, these systems are not able to affect fan speed or cooling capacity.
Therefore, a need exists for improvements in server management which will result in greater reliability and dependability of operation. Server users are in need of a management system by which the users can accurately gauge the health of their system. Users need a high availability system that should not only be resilient to faults, but should allow for maintenance, modification, and growth—-without downtime. System users should be able to replace failed components, and add new functionality, such as new network interfaces, disk interface cards and storage, without impacting existing users. As system demands grow, organizations must frequently expand, or scale, their computing infrastructure, adding new processing power, memory, storage and I/O capacity. With demand for 24-hour access to critical, server-based information resources, planned system downtime for system service or expansion has become unacceptable.
SUMMARY OF THE INVENTION
Embodiments of the inventive monitoring and management system provides system administrators with new levels of client/server system availability and management. It gives system administrators and network managers a comprehensive view into the underlying health of the server—in real time, whether on-site or off-site. In the event of a failure, the invention enables the administrator to learn why the system failed, why the system was unable to boot, and to control certain functions of the server.
One embodiment of the invention is a method for monitoring and diagnosing a computer, comprising: providing a computer connected to a microcontroller network; requesting conditions of the computer from the microcontroller network; sensing the conditions of the computer with the microcontroller network; receiving the sensed conditions in the microcontroller network; and communicating the sensed conditions from the microcontroller network to the source of the request.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is one embodiment of a top-level block diagram showing a fault tolerant computer system of the invention, including mass storage and network connections.
FIG. 2 is one embodiment of a block diagram showing a first embodiment of a multiple bus configuration connecting I/O adapters and a network of microcontrollers to the clustered CPUs of the fault tolerant computer system shown in FIG. 1 .
FIG. 3 is one embodiment of a block diagram showing a second embodiment of a multiple bus configuration connecting canisters containing I/O adapters and a network of microcontrollers to the clustered CPUs of the fault tolerant system shown in FIG. 1 .
FIG. 4 is one embodiment of a top-level block diagram illustrating the microcontroller network shown in FIGS. 2 and 3.
FIGS. 5A-5C are detailed block diagrams showing one embodiment of the microcontroller network shown in FIG. 4 illustrating the signals and values monitored by each microcontroller, and the control signals generated by the microcontrollers.
FIG. 6 is one embodiment of a flowchart showing the process by which a remote user can access diagnostic and managing services of the microcontroller network shown in FIGS. 4, 5 A- 5 C.
FIG. 7 is one embodiment of a block diagram showing the connection of an industry standard architecture (ISA) bus to the microcontroller network shown in FIGS. 4, 5 A- 5 C.
FIG. 8 is one embodiment of a flowchart showing the master to slave communications of the microcontrollers shown in FIGS. 4, 5 A- 5 C.
FIG. 9 is one embodiment of a flowchart showing the slave to master communications of the microcontrollers shown in FIGS. 4, 5 A- 5 C.
FIGS. 10A and 10B are flowcharts showing one process by which the System Interface, shown in FIGS. 4, 5 A- 5 C, gets commands and relays commands from the ISA bus to the network of microcontrollers.
FIGS. 11A and 11B are flowcharts showing one process by which a Chassis microcontroller, shown in FIGS. 4, 5 A- 5 C, manages and diagnoses the power supply to the computer system.
FIG. 12 is a flowchart showing one process by which the Chassis controller, shown in FIGS. 4, 5 A- 5 C, monitors the addition and removal of a power supply from the fault tolerant computer system.
FIG. 13 is a flowchart showing one process by which the Chassis controller, shown in FIGS. 4, 5 A- 5 C, monitors temperature.
FIGS. 14A and 14B are flowcharts showing one embodiment of the activities undertaken by CPU A controller, shown in FIGS. 4, 5 A- 5 C.
FIG. 15 is a detailed flowchart showing one process by which the CPU A controller, show in FIGS. 4, 5 A- 5 C, monitors the fan speed for the system board of the computer.
FIG. 16 is a flowchart showing one process by which activities of the CPU B controller, shown in FIGS. 4, 5 A- 5 C, scans for system faults.
FIG. 17 is a flowchart showing one process by which activities of a Canister controller, shown in FIGS. 4, 5 A- 5 C, monitors the speed of the canister fan of the fault tolerant computer system.
FIG. 18 is a flowchart showing one process by which activities of the System Recorder, shown in FIGS. 4, 5 A- 5 C, resets the NVRAM located on the backplane of the fault tolerant computer system.
DETAILED DESCRIPTION OF THE INVENTION
The following detailed description presents a description of certain specific embodiments of the present invention. However, the invention can be embodied in a multitude of different ways as defined and covered by the claims. In this description, reference is made to the drawings wherein like parts are designated with like numerals throughout.
FIG. 1 is one embodiment of a block diagram showing a fault tolerant computer system of the present invention. Typically the computer system is one server in a network of servers and communicating with client computers. Such a configuration of computers is often referred to as a client-server architecture. A fault tolerant server is useful for mission critical applications such as the securities business where any computer down time can result in catastrophic financial consequences. A fault tolerant computer will allow for a fault to be isolated and not propagate through the system thus providing complete or minimal disruption to continuing operation. Fault tolerant systems also provide redundant components such as adapters so service can continue even when one component fails.
The system includes a fault tolerant computer system 100 connecting to external peripheral devices through high speed I/O channels 102 and 104 . The peripheral devices communicate and are connected to the high speed I/O channels 102 and 104 by mass storage buses 106 and 107 . In different embodiments of the invention, the bus system 106 , 107 could be Peripheral Component Interconnect (PCI), Microchannel, Industrial Standard Architecture (ISA) and Extended ISA (EISA) architectures. In one embodiment of the invention, the buses 106 , 107 are PCI. Various kinds of peripheral controllers 108 , 112 , 116 , and 128 , may be connected to the buses 106 and 107 including mass storage controllers, network adapters and communications adapters. Mass storage controllers attach to data storage devices such as magnetic disk, tape, optical disk, CD-ROM. These data storage devices connect to the mass storage controllers using one of a number of industry standard interconnects, such as small computer storage interface (SCSI), IDE, EIDE, SMD. Peripheral controllers and I/O devices are generally off-the-shelf products. For instance, sample vendors for a magnetic disk controller 108 and magnetic disks 110 include Qlogic, and Quantum (respectively). Each magnetic disk may hold multiple Gigabytes of data.
A client server computer system typically includes one or more network interface controllers (NICs) 112 and 128 . The network interface controllers 112 and 128 allow digital communication between the fault tolerant computer system 100 and other computers (not shown) such as a network of servers via a connection 130 . For LAN embodiments of the network adapter, the network media used may be, for example, Ethernet (IEEE 802.3), Token Ring (IEEE 802.5), Fiber Distributed Datalink Interface (FDDI) or Asynchronous Transfer Mode (ATM).
In the computer system 100 , the high speed I/O channels, buses and controllers ( 102 - 128 ) may, for instance, be provided in pairs. In this example, if one of these should fail, another independent channel, bus or controller is available for use until the failed one is repaired.
In one embodiment of the invention, a remote computer 130 is connected to the fault tolerant computer system 100 . The remote computer 130 provides some control over the fault tolerant computer system 100 , such as requesting system status.
FIG. 2 shows one embodiment of the bus structure of the fault tolerant computer system 100 . A number ‘n’ of central processing units (CPUs) 200 are connected through a host bus 202 to a memory controller 204 , which allows for access to semiconductor memory by the other system components. In one embodiment of the invention, there are four CPUs 200 , each being an Intel Pentium® Pro microprocessor. A number of bridges 206 , 208 and 209 connect the host bus to three additional bus systems 212 , 214 , and 216 . These bridges correspond to high speed I/O channels 102 and 104 shown in FIG. 1 . The buses 212 , 214 and 216 correspond to the buses 106 and 107 shown in FIG. 1 . The bus systems 212 , 214 and 216 , referred to as PC buses, may be any standards-based bus system such as PCI, ISA, EISA and Microchannel. In one embodiment of the invention, the bus systems 212 , 214 , 216 are PCI. In another embodiment of the invention a proprietary bus is used.
An ISA Bridge 218 is connected to the bus system 212 to support legacy devices such as a keyboard, one or more floppy disk drives and a mouse. A network of microcontrollers 225 is also interfaced to the ISA bus 226 to monitor and diagnose the environmental health of the fault tolerant system. Further discussion of the network will be provided below.
A bridge 230 and a bridge 232 connects PC buses 214 and 216 with PC buses 234 and 236 to provide expansion slots for peripheral devices or adapters. Separating the devices 238 and 240 on PC buses 234 and 236 reduces the potential that a device or other transient I/O error will bring the entire system down or stop the system administrator from communicating with the system.
FIG. 3 shows an alternative bus structure embodiment of the fault tolerant computer system 100 . The two PC buses 214 and 216 contain bridges 242 , 244 , 246 and 248 to PC bus systems 250 , 252 , 254 , and 256 . As with the PC buses 214 and 216 , the PC buses 250 , 252 , 254 and 256 can be designed according to any type of bus architecture including PCI, ISA, EISA, and Microchannel. The PC buses 250 , 252 , 254 , and 256 are connected, respectively, to a canister 258 , 260 , 262 and 264 . The canisters 258 , 260 , 262 , and 264 are casings for a detachable bus system and provide multiple slots for adapters. In the illustrated canister, there are four adapter slots.
Referring now to FIG. 4, the present invention for monitoring and diagnosing environmental conditions may be implemented by using a network of microcontrollers 225 located on the fault tolerant computer system 100 . In one embodiment some of the microcontrollers are placed on a system board or motherboard 302 while other microcontrollers are placed on a backplane 304 . Furthermore, in the embodiment of FIG. 3, some of the microcontrollers such as Canister controller A 324 may reside on a removable canister.
FIG. 4 illustrates that the network of microcontrollers 225 is connected to one of the CPUs 200 by an ISA bus 308 . The ISA 308 bus interfaces the network of microcontrollers 225 which are connected on the microcontroller bus 310 through a System. Interface 312 . In one embodiment of the invention, the microcontrollers communicate through an I 2 C serial bus, also referred to as a microcontroller bus 310 . The document “The I 2 C Bus and How to Use It” (Philips Semiconductor, 1992) is hereby incorporated by reference. The I 2 C bus is a bi-directional two-wire bus and operates at a 400 kbps rate in the present embodiment. However, other bus structures and protocols could be employed in connection with this invention. In other embodiments, IEEE 1394 (Firewire), IEEE 422, IEEE 488 (GPIB), RS-185, Apple ADB, Universal Serial Bus (USB), or Controller Area Network (Can) could be utilized as the microcontroller bus. Control on the microcontroller bus is distributed. Each microcontroller can be a sender (a master) or a receiver (a slave) and each is interconnected by this bus. A microcontroller directly controls its own resources, and indirectly controls resources of other microcontrollers on the bus.
Here are some of the features of the I 2 C-bus:
Only two bus line are required: a serial data line (SDA) and a serial clock line (SCL).
Each device connected to the bus is software addressable by a unique address and simple master/slave relationships exist at all times; masters can operate as master-transmitters or as master-receivers.
The bus is a true multi-master bus including collision detection and arbitration to prevent data corruption if two or more masters simultaneously initiate data transfer.
Serial, 8-bit oriented, bi-directional data transfers can be made at up to 400 kbit/second in the fast mode.
Two wires, serial data (SDA) and serial clock (SCL), carry information between the devices connected to the I 2 C bus. Each device is recognized by a unique address and can operate as either a transmitter or receiver, depending on the function of the device. Further, each device can operate from time to time as both a transmitter and a receiver. For example, a memory device connected to the I 2 C bus could both receive and transmit data. In addition to transmitters and receivers, devices can also be considered as masters or slaves when performing data transfers (see Table 1). A master is the device which initiates a data transfer on the bus and generates the clock signals to permit that transfer. At that time, any device addressed is considered a slave.
TABLE 1
Definition of I 2 C-bus terminology
Term
Description
Transmitter
The device which sends the data to the bus
Receiver
The device which receives the data from the bus
Master
The device which initiates a transfer, generates
clock signals and terminates a transfer
Slave
The device addressed by a master
Multi-master
More than one master can attempt to control the bus
at the same time without corrupting the message.
Each device at separate times may act as a master.
Arbitration
Procedure to ensure that, if more than one master
simultaneously tries to control the bus, only one is
allowed to do so and the message is not corrupted
Synchronization
Procedure to synchronize the clock signal of two or
more devices
The I 2 C-bus is a multi-master bus. This means that more than one device capable of controlling the bus can be connected to it. As masters are usually microcontrollers, consider the case of a data transfer between two microcontrollers connected to the I 2 C-bus. This highlights the master-slave and receiver-transmitter relationships to be found on the I 2 C-bus. It should be noted that these relationships are not permanent, but only depend on the direction of data transfer at that time. The transfer of data between microcontrollers is further described in FIG. 8 .
The possibility of connecting more than one microcontroller to the I 2 C-bus means that more than one master could try to initiate a data transfer at the same time. To avoid the conflict that might ensue from such an event, an arbitration procedure has been developed. This procedure relies on the wired-AND connection of all I 2 C interfaces to the I 2 C-bus.
If two or more masters try to put information onto the bus, as long as they put the same information onto the bus, there is no problem. Each monitors the state of the SDL. If a microcontroller expects to find that the SDL is high, but finds that it is low, the microcontroller assumes it lost the arbitration and stops sending data. The clock signals during arbitration are a synchronized combination of the clocks generated by the masters using the wired-AND connection to the SCL line.
Generation of clock signal on the I 2 C-bus is always the responsibility of master devices. Each master microcontroller generates its own clock signals when transferring data on the bus.
In one embodiment, the command, diagnostic, monitoring and history functions of the microcontroller network 102 are accessed using a global network memory and a protocol has been defined so that applications can access system resources without intimate knowledge of the underlying network of microcontrollers. That is, any function may be queried simply by generating a network “read” request targeted at the function's known global network address. In the same fashion, a function may be exercised simply by “writing” to its global network address. Any microcontroller may initiate read/write activity by sending a message on the I 2 C bus to the microcontroller responsible for the function (which can be determined from the known global address of the function). The network memory model includes typing information as part of the memory addressing information.
Referring to FIG. 4, in one embodiment of the invention, the network of microcontrollers 310 includes ten processors. One of the purposes of the microcontroller network 225 is to transfer messages to the other components of the server system 100 . The processors or microcontrollers include: a System Interface 312 , a CPU A controller 314 , a CPU B controller 316 , a System Recorder 320 , a Chassis controller 318 , a Canister A controller 324 , a Canister B controller 326 , a Canister C controller 328 , a Canister D controller 330 and a Remote Interface controller 332 . The System Interface controller 312 , the CPU A controller 314 and the CPU B controller 316 are located on a system board 302 in the fault tolerant computer system 100 . Also located on the system board are one or more central processing units (CPUs) or microprocessors 164 and the Industry Standard Architecture (ISA) bus 296 that connects to the System Interface Controller 312 . The CPUs 200 may be any conventional general purpose single-chip or multi-chip microprocessor such as a Pentium 7 , Pentium® Pro or Pentium® II processor available from Intel Corporation, A MIPS® processor available from Silicon Graphics, Inc., a SPARC processor from Sun Microsystems, Inc., a Power PC® processor available from Motorola, or an ALPHA® processor available from Digital Equipment Corporation. In addition, the CPUs 200 may be any conventional special purpose microprocessor such as a digital signal processor or a graphics processor.
The System Recorder 320 and Chassis controller 318 , along with a data storage such as a random access non-volatile access memory (NVRAM) 322 that connects to the System Recorder 320 , are located on a backplane 304 of the fault tolerant computer system 100 . The data storage 322 may be independently powered and may retain its contents when power is unavailable. The data storage 322 is used to log system status, so that when a failure of the computer 100 occurs, maintenance personnel can access the storage 322 and search for information about what component failed. An NVRAM is used for the data storage 322 in one embodiment but other embodiments may use other types and sizes of storage devices.
The System Recorder 320 and Chassis controller 318 are the first microcontrollers to power up when server power is applied. The System Recorder 320 , the Chassis controller 318 and the Remote Interface microcontroller 332 are the three microcontrollers that have an independent bias 5 Volt power supplied to them if main server power is off. This independent bias 5 Volt power is provided by a Remote Interface Board (not shown). The Canister controllers 324 - 330 are not considered to be part of the backplane 304 because each is mounted on a card attached to the canister.
FIGS. 5A-5C are one embodiment of a block diagram that illustrates some of the signal lines that are used by the different microcontrollers. Some of the signal lines connect to actuators and other signal lines connect to sensors. In one embodiment of the invention the microcontrollers in the network are commercially available microcontrollers. Examples of off-the-shelf microcontrollers are the PIC16c65 and the PIC16c74 available from Microchip Technology Inc, the 8051 from Intel Corporation, the 8751 available from Atmel, and a P80CL580 microprocessor available from Philips, could be utilized.
The Chassis controller 318 is connected to a set of temperature detectors 502 , 504 , and 506 which read the temperature on the backplane 304 and the system board 302 . FIG. 5 also illustrates the signal lines that connect the System Recorder 320 to the NVRAM 322 and a timer chip 520 . In one embodiment of the invention, the System Recorder 320 is the only microcontroller that can access the NVRAM 322 . The Canister controller 324 is connected to a Fan Tachometer Signal Mux 508 which is used to detect the speed of the fans. The CPU A controller 314 also is connected to a fan mux 508 which gathers the fan speed of system fans. The CPU A controller 314 displays errors to a user by writing to an LCD display 512 . Any microcontroller can request the CPU A controller 314 to write a message to the LCD display 512 . The System Interface 312 is connected to a response buffer 514 which queues outgoing response signals in the order that they are received. Similarly, a request signal buffer 516 is connected to the System Interface 312 and stores, or queues request signals in the order that they are received.
Software applications can access the network of microcontrollers 225 by using the software program header file that is listed at the end of the specification in the section titled “Header File for Global Memory Addresses.” This header file provides a global memory address for each function of the microcontroller network 225 . By using the definitions provided by this header file, applications can request and send information to the microcontroller network 225 without needing to know where a particular sensor or activator resides in the microcontroller network.
FIG. 6 is one embodiment of a flowchart illustrating the process by which under one implementation of the present invention, a remote application connected, say, through the connection of FIG. 1, can access the network of microcontrollers 225 . Starting at state 600 , a remote software application, such as a generic system management application like Hewlett-Packard Open View, or an application specific to this computer system, retrieves a management information block (MIB) object by reading and interpreting a MIB file, or by an application's implicit knowledge of the MIB object's structure. This retrieval could be the result of an operator using a graphical user interface (GUI), or as the result of some automatic system management process. The MIB is a description of objects, which have a standard structure, and contain information specific to the MIB object ID associated with a particular MIB object. At a block 602 , the remote application builds a request for information by creating a request which references a particular MIB object by its object ID, sends the request to the target computer using a protocol called SNMP (simple network management protocol). SNMP is a type of TCP/IP protocol. Moving to state 604 , the remote software sends the SNMP packet to a local agent Microsoft WinSNMP, for example, which is running on the fault tolerant computer system 100 , which includes the network of microcontrollers 225 (FIG. 4 ). The agent is a specialized program which can interpret MIB object IDs and objects. The local agent software runs on one of the CPUs 200 of FIGS. 2 and 3.
The local agent examines the SNMP request packet (state 606 ). If the local agent does not recognize the request, the local agent passes the SNMP packet to an extension SNMP agent. Proceeding to state 608 , the extension SNMP agent dissects the object ID. The extension SNMP agent is coded to recognize from the object ID, which memory mapped resources managed by the network of microcontrollers need to be accessed (state 608 ). The agent then builds the required requests for the memory mapped information in the command protocol format understood by the network of microcontrollers 225 . The agent then forwards the request to a microcontroller network device driver (state 610 ).
The device driver then sends the information to the network of microcontrollers 225 at state 612 . The network of microcontrollers 225 provides a result to the device driver in state 614 . The result is returned to the extension agent, which uses the information to build the MIB object, and return it to the extension SNMP agent (state 616 ). The local SNMP agent forwards the MIB object via SNMP to the remote agent (state ( 616 ). Finally, in state 620 , the remote agent forwards the result to the remote application software.
For example, if a remote application needs to know the speed of a fan, the remote application reads a file to find the object ID for fan speed. The object ID for the fan speed request may be “837.2.3.6.2”. Each set of numbers in the object ID represent hierarchical groups of data. For example the number “3” of the object ID represents the cooling system. The “3.6” portion of the object ID represents the fans in the cooling. All three numbers “3.6.2” indicate speed for a particular fan in a particular cooling group.
In this example, the remote application creates a SNMP packet containing the object ID to get the fan speed on the computer 100 . The remote application then sends the SNMP packet to the local agent. Since the local agent does not recognize the fen speed object ID, the local agent forwards the SNMP packet to the extension agent. The extension agent parses the object ID to identify which specific memory mapped resources of the network of microcontrollers 225 are needed to build the MIB object whose object ID was just parsed. The extension agent then creates a message in the command protocol required by the network of microcontrollers 225 . A device driver which knows how to communicate requests to the network of microcontrollers 225 takes this message and relays the command to the network of microcontrollers 225 . Once the network of microcontrollers 225 finds the fan speed, it relays the results to the device driver. The device driver passes the information to the extension agent. The agent takes the information supplied by the microcontroller network device driver and creates a new SNMP packet. The local agent forwards this packet to the remote agent, which then relays the fan speed which is contained in the packet to the remote application program.
FIG. 7 is one embodiment of a block diagram of the interface between the network of microcontrollers 225 and the ISA bus 308 of FIGS. 2 and 3. The interface to the network of microcontrollers 225 includes a System Interface processor 312 which receives event and request signals, processes these signals, and transmits command, status and response signals to the operating system of the CPUs 200 . In one embodiment, the System Interface processor 312 is a PIC16C65 controller chip, available from Microchip, Technology Inc., which includes an event memory (not shown) organized as a bit vector, having at least sixteen bits. Each bit in the bit vector represents a particular type of event. Writing an event to the System Interface processor 312 sets a bit in the bit vector that represents the event. Upon receiving an event signal from another microcontroller, the System Interface 312 interrupts CPUs 200 . Upon receiving the interrupt, the CPUs 200 will check the status of the System Interface 312 to ascertain that an event is pending. Alternatively, the CPUs 200 may periodically poll the status of the System Interface 312 to ascertain whether an event is pending. The CPUs 200 may then read the bit vector in the System Interface 312 to ascertain the type of event that occurred and thereafter notify a system operator of the event by displaying an event message on a monitor connected to the fault tolerant computer 100 or another computer in the server network. After the system operator has been notified of the event, as described above, she may then obtain further information about the system failure which generated the event signal by accessing the NVRAM 322 .
The System Interface 312 communicates with the CPUs 200 by receiving request signals from the CPUs 200 and sending response signals back to the CPUs 200 . Furthermore, the System Interface 312 can send and receive status and command signals to and from the CPUs 200 . For example, a request signal may be sent from a software application inquiring as to whether the System Interface 312 has received any -vent signals, or inquiring as to the status of a particular processor, subsystem, operating parameter. The following discussion explains how in further detail at the state 612 , the device driver sends the request to the network on microcontrollers, and then, how the network on microcontrollers returns the result (state 614 ). A request signal buffer 516 is connected to the System Interface 312 and stores, or queues, request signals in the order that they are received, first in-first out (FIFO). Similarly, a response buffer 514 is connected to the System Interface 312 and queues outgoing response signals in the order that they are received (FIFO). These queues are one byte wide, (messages on the I 2 C bus are sequences of 8-bit bytes, transmitted bit serially on the SDL).
A message data register (MDR) 707 is connected to the request and response buffer 516 and 514 and controls the arbitration of messages to and from the System Interface 312 via the request and response buffers 516 and 514 . In one embodiment, the MDR 707 is eight bits wide and has a fixed address which may be accessed by the server's operating system via the ISA bus 226 connected to the MDR 707 . As shown in FIG. 7, the MDR 707 has an I/O address of 0 CC 0 h. When software application running on one of the CPUs 200 desires to send a request signal to the System Interface 312 , it does so by writing a message one byte at a time to the MDR 707 . The application then indicates to the system interface processor 312 that the command has been completely written, and may be processed.
The system interface processor 312 writes the response one byte at a time to the response queue, then indicates to the CPU (via an interrupt or a bit in the status register) that the response is complete, and ready to be read. The CPU 200 then reads the response queue one byte at a time by reading the MDR 707 until all bytes of the response are read.
The following is one embodiment of the command protocol used to communicate with the network of microcontrollers 225 .
TABLE 2
Command Protocol Format
The following is a description of each of the fields in the command protocol.
TABLE 3
Description of Command Protocol Fields
FIELD
DESCRIPTION
Slave Addr
Specifies the processor identification code. This
field is 7 bits wide. Bit [7 . . . 1].
LSBit
Specifies what type of activity is taking place. If
LSBit is clear (0), the master is writing to a slave.
If LSBit is set (1), the master is reading from a
slave.
MSBit
Specifies the type of command. It is bit 7 of byte
1 of a request. If this bit is clear (0), this is a
write command. If it is set (1), this is a read
command.
Type
Specifies the data type of this command, such as
bit or string.
Command ID (LSB)
Specifies the least significant byte of the address
of the processor.
Command ID (MSB)
Specifies the most significant byte of the address
of the processor.
Length (N)
Read Request
Specifies the length of the data that the master
expects to get back from a read response. The
length, which is in bytes, does not include the
Status, Check Sum, and Inverted Slave Addr
fields.
Read Response
Specifies the length of the data immediately
following this byte, that is byte 2 through byte
N + 1. The length, which is in bytes, does not
include the Status, Check Sum, and Inverted
Slave Addr fields.
Write Request
Specifies the length of the data immediately
following this byte, that is byte 2 through byte
N + 1. The length, which is in bytes, does not
include the Status, Check Sum, and Inverted
Slave Addr fields.
Write Response
Always specified as 0.
Data Byte 1
Specifies the data in a read request and response,
and a write request.
Data Byte N
Status
Specifies whether or not this command executes
successfully. A non-zero entry indicates a failure.
Check Sum
Specifies a direction control byte to ensure the
integrity of a message on the wire.
Inverted Slave Addr
Specifies the Slave Addr, which is inverted.
The System Interface 312 further includes a command and status register (CSR) 709 which initiates operations and reports on status. The operation and functionality of CSR 709 is described in further detail below. Both synchronous and asynchronous I/O modes are provided by the System Interface 312 . During a synchronous mode of operation, the device driver waits for a request to be completed. During an asynchronous mode of operation the device driver sends the request, and asks to be interrupted when the request completes. To support asynchronous operations, an interrupt line 711 is connected between the System Interface 312 and the ISA bus 226 and provides the ability to request an interrupt when asynchronous I/O is complete, or when an event occurs while the interrupt is enabled. As shown in FIG. 7, in one embodiment, the address of the interrupt line 711 is fixed and indicated as IRQ 15 which is an interrupt address number used specifically for the ISA bus 226 .
The MDR 707 and the request and response buffers 516 and 514 , respectively, transfer messages between a software application running on the CPUs 200 and the failure reporting system of the invention. The buffers 516 and 514 have two functions: (1) they store data in situations where one bus is running faster than the other, i.e., the different clock rates, between the ISA bus 226 and the microcontroller bus 310 ; and (2) they serve as interim buffers for the transfer of messages—this relieves the System Interface 312 of having to provide this buffer.
When the MDR 707 is written to by the ISA bus 226 , it loads a byte into the request buffer 516 . When the MDR 707 is read from the ISA bus 516 , it unloads a byte from the response buffer 514 . The System Interface 312 reads and executes messages from buffer 516 when a message command is received in the CSR 709 . A response message is written to the response buffer 514 when the System Interface 312 completes executing the command. The system operator receives a completed message over the microcontroller bus 310 . A software application can read and write message data to and from the buffers 516 and 514 by executing read and write instructions through the MDR 707 .
The CSR 709 has two functions. The first is to initiate commands, and the second is to report status. The System Interface commands are usually executed synchronously. That is, after issuing a command, the microcontroller network device driver should continue to poll the CSR 709 status to confirm command completion. In addition to synchronous I/O mode, the microcontroller network device driver can also request an asynchronous I/O mode for each command by setting a “Asyn Req” bit in the command. In this mode, an interrupt is generated and sent to the ISA bus 226 , via the interrupt line 711 , after the command has completed executing.
In the described embodiment, the interrupt is asserted through IRQ 15 of the ISA programmable interrupt controller (PIC). The ISA PIC interrupts the CPU 200 s when a signal transitioning from high to low, or from low to high, is detected at the proper input pin (edge triggered). Alternatively, the interrupt line 711 may utilize connect to a level-triggered input. A level-triggered interrupt request is recognized by keeping the signal at the same level, or changing the level of a signal, to send an interrupt. The microcontroller network device driver can either enable or disable interrupts by sending “Enable Ints” and “Disable Ints” commands to the CSR 701 . If the interrupt 711 line is enabled, the System Interface 312 asserts the interrupt signal IRQ 15 of the PIC to the ISA bus 226 , either when an asynchronous I/O is complete or when an event has been detected.
In the embodiment shown in FIG. 2, the System Interface 312 may be a single-threaded interface. Since messages are first stored in the queue, then retrieved from the queue by the other side of the interface, a device driver should write one message, containing a sequence of bytes, at a time. Thus, only one message should be in progress at a time using the System Interface 312 . Therefore, a program or application must allocate the System Interface 312 for its use before using it, and then de-allocate the interface 514 when its operation is complete. The CSR 709 indicates which operator is allocated access to the System Interface 312 .
Referring to FIGS. 2 and 7, an example of how messages are communicated between the System Interface 312 and CPUs 200 in one embodiment of the invention is as follows (all byte values are provided in hexadecimal numbering). A system management program (not shown) sends a command to the network of microcontrollers 225 to check temperature and fan speed. To read the temperature from CPU A controller 314 the program builds a message for the device driver to forward to the network of microcontrollers 225 . First, the device driver on CPUs 200 allocates the interface by writing the byte “01” to the CSR 709 . If another request was received, the requestor would have to wait until the previous request was completed. To read the temperature from Chassis controller 318 the device driver would write into the request queue 516 through the MDR 707 the bytes “02 83 03 00 FF”. The first byte “02” would signify to the System Interface 312 that a command is intended for the Chassis controller 318 . The first bits of the second byte “83” indicates that a master is writing to a slave. The last or least significant three bits of the byte “83” indicate the data type of the request. The third and fourth bytes “03 00” indicate that the read request temperature function of the Chassis controller 318 is being requested. The final byte “FF” is the checksum.
After writing the bytes to the MDR 707 , a “13” (message command) is written by the device driver to the CSR 709 , indicating the command is ready to be executed. The System Interface processor 312 passes the message bytes to the microcontroller bus 310 , receives a response, and puts the bytes into the response FIFO 514 . Since there is only one system interface processor 312 , there is no chance that message bytes will get intermingled.
After all bytes are written to the response FIFO, the System Interface processor 312 sets a bit in the CSR 709 indicating message completion. If directed to do so by the device driver, the system interface 312 asserts an interrupt on IRQ 15 upon completion of the task.
The CPUs 200 would then read from the response buffer 516 through the MDR 707 the bytes “02 05 27 3C 27 26 27 00”. The first byte in the string is the slave address shown as Byte 0 in the Read Response Format. The first byte 02 indicates that the CPU A Chassis controller 318 was the originator of the message. The second byte “05” indicates the number of temperature readings that follow. The second Byte “05” maps to Byte 1 of the Read Response Format. In this example, the Chassis con:roller 318 returned five temperatures. The second reading, byte “3C” (60 decimal) is above normal operational values. The last byte “00” is a check sum which is used to ensure the integrity of a message.
The CPUs 200 agent and device driver requests the fan speed by writing the bytes “03 83 04 00 FF” to the network of microcontroller 225 . Each byte follows the read request format specified in Table 2. The first byte “03” indicates that the command is for the CPU A Controller 314 . The second byte “83” indicates that the command is a read request of a string data type.
A response of “03 06 41 43 41 42 41 40 00” would be read from MDR 707 by the device driver. The first byte “03” indicates to the device driver that the command is from the CPU A controller 314 . The speed bytes “41 43 41 42 41 40” indicate the revolutions per second of a fan in hexadecimal. The last byte read from the MDR 707 “00” is the checksum.
Since one of the temperatures is higher than the warning threshold, 55° C., and fan speed is within normal (low) range, a system administrator or system management software may set the fan speed to high with the command bytes “03 01 01 00 01 01 FF”. The command byte “03” indicates that the command is for the CPU A 314 . The first byte indicates that a write command is requested. The third and fourth bytes, which correspond to byte 2 and 3 of the write request format, indicate a request to increase the fan speed. The fifth byte, which corresponds to byte 4 of the write request format indicates to the System Interface 312 that one byte is being sent. The sixth byte contains the data that is being sent. The last byte “FF” is the checksum.
FIG. 8 is one embodiment of a flowchart describing the process by which a master microcontroller communicates with a slave microcontroller. Messages between microcontrollers can be initiated by any microcontroller on the microcontroller bus 310 (FIG. 4 ). A master microcontroller starts out in state 800 .
In state 802 , the microcontroller arbitrates for the start bit. If a microcontroller sees a start bit on the microcontroller bus 310 , it cannot gain control of the microcontroller bus 310 . The master microcontroller proceeds to state 804 . In the state 804 , the microcontroller increments a counter every millisecond. The microcontroller then returns to state 800 to arbitrate again for the start bit. If at state 806 the count reaches 50 ms, the master has failed to gain the bus (states 808 and 810 ). The microcontroller then returns to the state 800 to retry the arbitration process.
If in the state 802 , no start bit is seen on the microcontroller bus 310 , the microcontroller bus 310 is assumed to be free (i.e., the microcontroller has successfully arbitrated won arbitration for the microcontroller bus 310 ). The microcontroller sends a byte at a time on the microcontroller bus 310 (state 812 ). After the microcontroller has sent each byte, the microcontroller queries the microcontroller bus 310 to insure that the microcontroller bus 310 is still functional. If the SDA and SCL lines of the microcontroller bus 310 are not low, the microcontroller is sure that the microcontroller bus 310 is functional and proceeds to state 816 . If the SDA and SCL lines are not drawn high, then the microcontroller starts to poll the microcontroller bus 310 to see if it is functional. Moving to state 819 , the microcontroller increments a counter Y and waits every 22 microseconds. If the counter Y is less than five milliseconds (state 820 ), the state 814 is reentered and the microcontroller bus 310 is checked again. If the SDA and SCL lines are low for 5 milliseconds (indicated when, at state 820 , the counter Y exceeds 5 milliseconds), the microcontroller enters state 822 and assumes there is a microcontroller bus error. The microcontroller then terminates its control of the microcontroller bus 310 (state 824 ).
If in the state 814 , the SDA/SCL lines do not stay low (state 816 ), the master microcontroller waits for a response from a slave microcontroller (state 816 ). If the master microcontroller has not received a response, the microcontroller enters state 826 . The microcontroller starts a counter which is incremented every one millisecond. Moving to state 828 , if the counter reaches fifty milliseconds, the microcontroller enters state 830 indicating a microcontroller bus error. The microcontroller then resets the microcontroller bus 310 (state 832 ).
Returning to state 816 , if the master microcontroller does receive a response in state 816 , the microcontroller enters state 818 and receives the data from the slave microcontroller. At state 820 , the master microcontroller is finished communicating with the slave microcontroller.
FIG. 9 is one embodiment of a block diagram illustrating the process by which a slave microcontroller communicates with a master microcontroller. Starting in state 900 , the slave microcontroller receives a byte from a master microcontroller. The first byte of an incoming message always contains the slave address. This slave address is checked by all of the microcontrollers on the microcontroller bus 310 . Whichever microcontroller matches the slave address to its own address handles the request
At a decision state 902 , an interrupt is generated on the slave microcontroller. The microcontroller checks if the byte received is the first received from the master microcontroller (state 904 ). If the current byte received is the first byte received, the slave microcontroller sets a bus time-out flag (state 906 ). Otherwise, the slave microcontroller proceeds to check if the message is complete (state 908 ). If the message is incomplete, the microcontroller proceeds to the state 900 to receive the remainder of bytes from the master microcontroller. If at state 908 , the slave microcontroller determines that the complete message has been received, the microcontroller proceeds to state 909 .
Once the microcontroller has received the first byte, the microcontroller will continue to check if there is an interrupt on the microcontroller bus 310 . If no interrupt is posted on the microcontroller bus 310 , the slave microcontroller will check to see if the bus time-out flag is set. The bus time-out flag is set once a byte has been received from a master microcontroller. If in the decision state 910 the microcontroller determines that the bus time-out flag is set, the slave microcontroller will proceed to check for an interrupt every 10 milliseconds up to 500 milliseconds. For this purpose, the slave microcontroller increments the counter every 10 milliseconds (state 912 ). In state 914 , the microcontroller checks to see if the microcontroller bus 310 has timed out. If the slave microcontroller has not received additional bytes from the master microcontroller, the slave microcontroller assumes that the microcontroller bus 310 is hung and resets the microcontroller bus 310 (state 916 ). Next, the slave microcontroller aborts the request and awaits further requests from other master microcontrollers (state 918 ).
Referring to the state 909 , the bus timeout bit is cleared, and the request is processed and the response is formulated. Moving to state 920 , the response is sent a byte at a time. At state 922 , the same bus check is made as was described for the state 814 . States 922 , 923 and 928 form the same bus check and timeout as states 814 , 819 and 820 . If in state 928 this check times out, a bus error exists, and this transaction is aborted (states 930 and 932 ).
FIGS. 10A and 10B are flow diagrams showing one process by which the System Interface 312 handles requests from other microcontrollers in the microcontroller network and the ISA bus 226 (FIGS. 4 and 5 ). The System Interface 312 relays messages from the ISA bus 226 to other microcontrollers in the network of microcontrollers 225 . The System Interface 312 also relays messages from the network of microcontrollers to the ISA bus 226 .
Referring to FIGS. 10A and 10B, the System Interface 312 initializes all variables and the stack pointer (state 1000 ). Moving to state 1002 , the System Interface 312 starts its main loop in which it performs various functions. The System Interface 312 next checks the bus timeout bit to see if the microcontroller bus 310 has timed-out (decision state 1004 ). If the microcontroller bus 310 has timed-out, the System Interface 312 resets the microcontroller bus 310 in state 1006 .
Proceeding to a decision state 1008 , the System Interface 312 checks to see if any extent messages have been received. An event occurs when the System Interface 312 receives information from another microcontroller regarding a change to the state of the system. At state 1010 , the System Interface 312 sets the event bit in the CSR 709 to one. The System Interface 312 also sends an interrupt to the operating system if the CSR 709 has requested interrupt notification.
Proceeding to a decision state 1012 , the System Interface 312 checks to see if a device driver for the operating system has input a command to the CSR. If the System Interface 312 does not find a command, the System Interface 312 returns to state 1002 . If the System Interface does find a command from the operating system, the System Interface parses the command. For the “allocate command”, the System Interface 312 resets the queue to the ISA bus 226 resets the done bit in the CSR 709 (state 1016 ) and sets the CSR Interface Owner ID (state 1016 ). The Owner ID bits identify which device driver owns control of the System Interface 312 .
For the “de-allocate command”, the System Interface 312 resets the queue to the ISA bus 226 , resets the done bit in the CSR 709 , and clears the Owner ID bits (state 1018 ).
For the “clear done bit command” the System Interface 312 clears the done bit in the CSR 709 (state 1020 ). For the “enable interrupt command” the System Interface 312 sets the interrupt enable bit in the CSR 709 (state 1022 ). For the “disable interrupt command,” the System Interface 312 sets the interrupt enable bit in the CSR 709 (state 1024 ). For the “clear interrupt request command”, the System Interface 312 clears the interrupt enable bit in the CSR 709 (state 1026 ).
If the request from the operating system was not meant for the System Interface 312 , the command is intended for another microcontroller in the network 225 . The only valid command remaining is the “message command.” Proceeding to state 1028 , the System Interface 312 reads message bytes from the request buffer 516 . From the state 1028 , the System Interface 312 proceeds to a decision state 1030 in which the System Interface 312 checks whether the command was for itself. If the command was for the System Interface 312 , moving to state 1032 , the System Interface 312 processes the command. If the ID did not match an internal command address, the System Interface 312 relays the command the appropriate microcontroller (state 1034 ) by sending the message bytes out over the microcontroller bus 310 .
FIGS. 11A and 11B are flowcharts showing an embodiment of the functions performed by the Chassis controller 318 . Starting in the state 1100 , the Chassis controller 318 initializes its variables and stack pointer.
Proceeding to state 1102 , the Chassis controller 318 reads the serial numbers of the microcontrollers contained on the system board 302 and the backplane 304 . The Chassis controller 318 also reads the serial numbers for the Canister controllers 324 , 326 , 328 and 330 . The Chassis controller 318 stores all of these serial numbers in the NVRAM 322 .
Next, the Chassis controller 318 start its main loop in which it performs various diagnostics (state 1104 ). The Chassis controller 318 checks to see if the microcontroller bus 310 has timed-out (state 1106 ). If the bus has timed-out, the Chassis controller 318 resets the microcontroller bus 310 (state 1008 ). If the microcontroller bus 310 has not timed out the Chassis controller proceeds to a decision state 1110 in which the Chassis controller 318 checks to see if a user has pressed a power switch.
If the Chassis controller 318 determines a user has pressed a power switch, the Chassis controller changes the state of the power to either on or off (state 1112 ). Additionally, the Chassis controller logs the new power state into the NVRAM 322 .
The Chassis controller 318 proceeds to handle any power requests from the Remote Interface 332 (state 1114 ). As shown in FIG. 9, a power request message to this microcontroller is received when the arriving message interrupts the microcontroller. The message is processed and a bit is set indicating request has been made to toggle power. At state 1114 , the Chassis controller 318 checks this bit. If the bit is set, the Chassis controller 318 toggles the system, i.e., off-to-on or on-to-off, power and logs a message into the NVRAM 322 that the system power has changed state (state 1116 ).
Proceeding to state 1118 , the Chassis controller 318 checks the operating system watch dog counter for a time out. If the Chassis controller 318 finds that the operating system has failed to update the timer, the Chassis controller 318 proceeds to logs a message with the NVRAM 322 (state 1120 ). Additionally, the Chassis controller 318 sends an event to the System Interface 312 and the Remote Interface 332 .
Since it takes some time for the power supplies to settle and produce stable DC power, the Chassis controller delays before proceeding to check DC (state 1122 ).
The Chassis controller 318 then checks for changes in the canisters 258 - 264 (state 1124 ), such as a canister being inserted or removed. If a change is detected, the Chassis controller 318 logs a message to the NVRAM 322 (state 1126 ). Additionally, the Chassis controller 318 sends an event to the System Interface 312 and the Remote Interface 332 .
The Chassis controller 318 proceeds to check the power supply for a change in status (state 1128 ). The process by which the Chassis controller 318 checks the power supply is described in further detail in the discussion for FIG. 12 .
The Chassis controller then checks the temperature of the system (state 1132 ). The process by which the Chassis controller 318 checks the temperature is described in further detail in the discussion for FIG. 13 .
At state 1136 , the Chassis controller 318 reads all of the voltage level signals. The Chassis controller 318 saves these voltage levels values in an internal register for reference by other microcontrollers.
Next, the Chassis controller 318 checks the power supply signals for AC/DC changes (state 1138 ). If the Chassis controller 318 detects a change in the Chassis controller 318 , the Chassis controller 318 logs a message to the NVRAM 322 (state 1140 ). Additionally, the Chassis controller 318 sends an event to the System Interface 312 and the Remote Interface 332 that a AC/DC signal has changed. The Chassis controller 318 then returns to state 1104 to repeat the monitoring process.
FIG. 12 is a flowchart showing one process by which the Chassis controller 318 checks the state of the redundant power supplies termed number 1 and 2 . These power supplies are monitored and controlled by the chassis controller 318 through the signal lines shown in FIG. 5 A. When a power supply fails or requires maintenance, the other supply maintains power to the computer 100 . To determine whether a power supply is operating properly or not, its status of inserted or removed (by maintenance personnel) should be ascertained. Furthermore, a change in status should be recorded in the NVRAM 322 . FIG. 12 describes in greater detail the state 1128 shown in FIG. 11 B.
Starting in state 1202 , the Chassis controller 318 checks the power supply bit. If the power supply bit indicates that a power supply should be present, the Chassis controller checks whether power supply “number 1 ” has been removed (state 1204 ). If power supply number 1 has been removed, the chassis microcontroller 318 checks whether its internal state indicates power supply number one should be present. If the internal state was determined to be present, then the slot is checked to see whether power supply number 1 is still physically present (state 1204 ). If power supply number 1 has been removed, the PS_PRESENT#1 bit is changed to not present (state 1203 ). The Chassis controller 318 then logs a message in the NVRAM 322 .
Referring to state 1206 , if the PS_PRESENT#1 bit indicates that power supply number 1 is not present, the Chassis controller 318 checks whether power supply number 1 has been inserted (i.e., checks to see if it is now physically present) (state 1206 ). If it has been inserted, the Chassis controller 318 then logs a message into the NVRAM 322 that the power supply number 1 has been inserted (state 1210 ) and changes the value of PS_PRESENT#1 to present.
After completion, states 1204 , 1206 , 1208 , and 1210 proceed to state 1212 to monitor power supply number 2 . The Chassis controller 318 checks whether the PS_PRESENT#2 bit is set to present. If the PS_PRESENT#2 bit indicates that power supply “number 2 ” should be there, the Chassis controller 318 proceeds to state 1224 . Otherwise, the Chassis controller 318 proceeds to state 1226 . At state 1224 , the Chassis controller 318 checks if power supply number 2 is still present. If power supply number 2 has been removed, the Chassis controller 318 logs in the NVRAM 322 that power supply number 2 has been removed (state 1228 ). The chassis controller also changes the value of PS_PRESENT#2 bit to not present.
Referring to decision state 1226 , if the PS_PRESENT#2 bit indicates that no power supply number 2 is present, the Chassis controller 318 checks if power supply number 2 has been inserted. If so, the Chassis controller 318 then logs a message into the NVRAM 322 that power supply number 2 has been inserted and changes the value of PS_PRESENT#2 to present (state 1230 ). After completion of states 1224 , 1226 , 1228 , and 1230 , the chassis controller 318 proceeds to state 1232 to monitor the AC/DC power supply changed signal.
If in decision state 1234 the Chassis controller 318 finds that the AC/DC power supply changed signal from the power supplies is asserted, the change in status is recorded in state 1236 . The Chassis controller 318 continues the monitoring process by proceeding to the state 1132 in FIG. 11 B.
FIG. 13 is a flowchart showing one process by which the Chassis controller 318 monitors the temperature of the system. As shown in FIG. 5A, the Chassis controller 318 receives temperature detector signal lines from five temperature detectors located on the backplane and the motherboard. If either component indicates it is overheating, preventative action may be taken manually, by a technician, or automatically by the network of microcontrollers 225 . FIG. 13 describes in greater detail the state 1132 shown in FIG. 11 B.
To read the temperature of the Chassis, the Chassis controller 318 reads the temperature detectors 502 , 504 , and 506 (state 1300 ). In the embodiment of the invention shown in FIG. 13 there are five temperature detectors (two temperature detectors not shown). Another embodiment includes three temperature detectors as shown.
The Chassis controller 318 checks the temperature detector 502 to see if the temperature is less than −25° C. or if the temperature is greater than or equal to 55° C. (state 1308 ). Temperatures in this range are considered normal operating temperatures. Of course, other embodiments may use other temperature ranges. If the temperature is operating inside normal operating boundaries, the Chassis controller 318 proceeds to state 1310 . If the temperature is outside normal operating boundaries, the Chassis controller 318 proceeds to state 1312 . At state 1312 , the Chassis controller 318 evaluates the temperature a second time to check if the temperature is greater than or equal to 70° C. or less than or equal to −25° C. If the temperature falls below or above outside of these threshold values, the Chassis controller proceeds to state 1316 . Temperatures in this range are considered so far out of normal operating temperatures, that the computer 100 should be shutdown. Of course, other temperature ranges may be used in other embodiments.
Referring to state 1316 , if the temperature level reading is critical, the Chassis controller 318 logs a message in the NVRAM 322 that the system was shut down due to excessive temperature. The Chassis controller 318 then proceeds to turn off power to the system in state 1320 , but may continue to operate from a bias or power supply.
Otherwise, if the temperature is outside normal operating temperatures, but only slightly deviant, the Chassis controller 318 sets a bit in the temperature warning status register (state 1314 ). Additionally, the Chassis controller 318 logs a message in the NVRAM 322 that the temperature is reaching dangerous levels (state 1318 ).
The Chassis controller 318 follows the aforementioned process for each temperature detector on the system. Referring back to state 1310 , which was entered after determining a normal temperature from one of the temperature detectors, the Chassis controller 318 checks a looping variable “N” to see if all the sensors were read. If all sensors were not read, the Chassis controller 318 returns to state 1300 to read another temperature detector. Otherwise, if all temperature detectors were read, the Chassis controller 318 proceeds to state 1322 . At state 1322 , the Chassis controller 318 checks a warning status register (not shown). If no bit is set in the temperature warning status register, the Chassis controller 318 returns to the state 1136 in FIG. 11 B. If the Chassis controller 318 determines that a bit in the warning status register was set for one of the sensors, the Chassis controller 318 proceeds to recheck all of the sensors (state 1324 ). If the temperature of the sensors are still at a dangerous level, the Chassis Controller 318 maintains the warning bits in the warning status register. The Chassis controller 318 then proceeds to the state 1136 (FIG. 11 B). At state 1324 , if the temperatures of the sensors are now at normal operating values, the Chassis controller 318 proceeds to clear all of the bits in the warning status register (state 1326 ). After clearing the register, the Chassis controller 318 proceeds to state 1328 to log a message in the NVRAM 322 that the temperature has returned to normal operational values, and the Chassis controller 318 proceeds to the state 11136 (FIG. 11 B).
FIGS. 14A and 14B are flowcharts showing the functions performed by one embodiment of the CPU A controller 314 . The CPU A controller 314 is located on the system board 302 and conducts diagnostic checks for: a microcontroller bus timeout, a manual system board reset, a low system fan speed, a software reset command, general faults, a request to write to flash memory, checks system flag status, and a system fault.
The CPU A controller 314 , starting in state 1400 , initializes its variables and stack pointer. Next, in state 1402 the CPU A controller 314 starts its main loop in which it performs various diagnostics which are described below. At state 1404 , the CPU A controller 314 checks the microcontroller bus 310 for a time out. If the microcontroller bus 310 has timed out, the CPU A controller 314 resets the microcontroller bus 310 (state 1406 ). From either state 1404 or 1406 , the CPU A controller 314 proceeds to check whether the manual reset switch (not shown) is pressed on the system board 302 (decision state 1408 ). If the CPU A controller 314 determines that the manual reset switch is pressed, the CPU A controller resets system board by asserting a reset signal (state 1410 ).
From either state 1408 or 1410 , the CPU A controller 314 proceeds to check the fan speed (decision state 1412 ). If any of a number of fans speed is low (see FIG. 15 and discussion below), the CPU A controller 314 logs a message to NVRAM 322 (state 1414 ). Additionally, the CPU A controller 314 sends an event to the Remote Interface 334 and the System Interface 312 . The CPU A controller 314 next proceeds to check whether a software reset command was issued by either the computer 100 or the remote computer 132 (state 1416 ). If such a command was sent, the CPU A controller 314 logs a message in NVRAM 322 that system software requested the reset command (state 1418 ). Additionally, the CPU A controller 314 also resets the system bus 202 .
From either state 1416 or 1418 , the CPU A controller 314 checks the flags bits (not shown) to determine if a user defined system fault occurred (state 1420 ). If the CPU A controller 314 determines that a user defined system fault occurred, the CPU A controller 314 proceeds to display the fault on an LCD display 512 (FIG. 5B) (state 1422 ).
From either state 1420 or 1422 the CPU A controller 314 proceeds to a state 1424 (if flash bit was not enabled) to check the flash enable bit maintained in memory on the CPU B controller 316 . If the flash enable bit is set, the CPU A controller 314 displays a code for flash enabled on the LCD display 512 . The purpose of the flash enable bit is further described in the description for the CPU B controller 316 (FIG. 16 ).
From either state 1424 or 1426 (if the flash bit was not enabled), the CPU A controller 314 proceeds to state 1428 and checks for system faults. If the CPU A controller 314 determines that a fault occurred, the CPU A controller 314 displays the fault on the LCD display 512 (state 1430 ). From state 1428 if no fault occurred, or from state 1430 , the CPU A controller 314 proceeds to the checks the system status flag located in the CPU A controller's memory (decision state 1432 ). If the status flag indicates an error, the CPU A controller 314 proceeds to state 1434 and displays error information on the LCD display 512 .
From either state 1432 or 1434 , the CPU controller proceeds to state 1402 to repeat the monitoring process.
FIG. 15 is a flowchart showing one process by which the CPU A controller 314 monitors the fan speed. FIG. 15 is a more detailed description of the function of state 1412 in FIG. 1 4 A. Starting in state 1502 , the CPU A controller 314 reads the speed of each of the fans 1506 , 1508 , and 1510 . The fan speed is processed by a Fan Tachometer Signal Mux 508 (also shown in FIG. 5B) which updates the CPU A controller 314 . The CPU A controller 314 then checks to see if a fan speed is above a specified threshold (state 1512 ). If the fan speed is above the threshold, the CPU A controller 314 proceeds to state 1514 . Otherwise, if the fan speed is operating below a specified low speed limit, the CPU A controller 314 proceeds to state 1522 .
On the other hand, when the fan is operating above the low speed limit at state 1514 , the CPU A controller 314 checks the hot_swap_fan register (not shown) if the particular fan was hot swapped. If the fan was hot swapped, the CPU A controller 314 proceeds to clear the fan's bit in both the fan_fault register (not shown) and the hot_swap_fan register (state 1516 ). After clearing these bits, the CPU A controller 314 checks the fan fault register (state 1518 ). If the fan fault register is all clear, the CPU A controller 314 proceeds to set the fan to low speed (state 1520 ) and logs a message to the NVRAM 322 . The CPU A controller 314 then proceeds to state 1536 to check for a temperature warning.
Now, referring back to state 1522 , if a fan speed is below a specified threshold limit, the CPU A controller 314 checks to see if the fan's speed is zero. If the fan's speed is zero, the CPU A controller 314 sets the bit in the hot_swap_fan register in state 1524 to indicate that the fan has a fault and should be replaced. If the fan's speed is not zero, the CPU A controller 314 will proceed to set a bit in the fan_fault register (state 1526 ). Moving to state 1528 , the speed of any fans still operating is increased to high, and a message is written to the NVRAM 322 .
In one alternative embodiment, the system self-manages temperature as follows: from either state 1520 or 1528 , the CPU A controller 314 moves to state 1536 and checks whether a message was received from the Chassis controller 318 indicating temperature warning. If a temperature warning is indicated, and if there are no fan faults involving fans in the cooling group associated with the warning, the speed of fans in that cooling group is increased to provide more cooling capacity (state 1538 ).
Proceeding to state 1530 from either state 1536 or 1538 , the CPU A controller 314 increments a fan counter stored inside of microcontroller memory. If at state 1531 , there are more fans to check, the CPU A controller 314 returns to state 1502 to monitor the speed of the other fans. Otherwise, the CPU controller 314 returns to state 1416 (FIG. 14 ).
FIG. 16 is one embodiment of a flow diagram showing the functions performed by the CPU B controller 316 . The CPU B controller 316 scans for system faults, scans the microcontroller bus 310 , and provides flash enable. The CPU B controller 316 , starting at state 1600 , initializes its variables and stack pointer.
After initializing its internal state, the CPU B controller 316 enters a diagnostic loop at state 1602 . The CPU B controller 316 then checks the microcontroller bus 310 for a time out (decision state 1604 ). If the microcontroller bus 310 has timed out, the CPU B controller 316 resets the microcontroller bus 310 in state 1606 . If the microcontroller bus 310 has not timed out (state 1604 ) or after state 1606 , the CPU B controller 316 proceeds to check the system fault register (not shown) (decision state 1608 ).
If the CPU B controller 316 finds a system fault, the CPU B controller 316 proceeds to log a message into the NVRAM 322 stating that a system fault occurred (state 1610 ). The CPU B controller 316 then sends an event to the System Interface 312 and the Remote Interface 332 . Additionally, the CPU B controller 316 turns on one of a number of LED indicators 518 (FIG. 5 B).
If no system fault occurred, or from state 1610 , the CPU B controller 316 scans the microcontroller bus 310 (decision state 1612 ). If the microcontroller bus 310 is hung then the CPU B controller 316 proceeds to flash an LED display 512 that the microcontroller bus 310 is hung (state 1614 ). Otherwise, if the bus is not hung the CPU B controller 316 then proceeds to state 1624 .
The CPU B controller 316 proceeds to check for a bus stop bit time out (decision state 1624 ). If the stop bit has timed out, the CPU B controller 316 generates a stop bit on the microcontroller bus for error recovery in case the stop bit is inadvertently being held low by another microcontroller (state 1626 ).
From either state 1624 or 1626 , the CPU B controller 316 proceeds to check the flash enable bit to determine if the flash enable bit (not shown) is set (state 1628 ). If the CPU B controller 316 determines that the flash enable bit is set (by previously having received a message requesting it), the CPU B controller 316 proceeds to log a message to the NVRAM 322 (state 1630 ). A flash update is performed by the BIOS if the system boot disk includes code to update a flash memory (not shown). The BIOS writes new code into the flash memory only if the flash memory is enabled for writing. A software application running on the CPUs 200 can send messages requesting that BIOS flash be enabled. At state 1630 , the 12 Volts needed to write the flash memory is turned on or left turned on. If the flash enable bit is not on, control passes to state 1629 , where the 12 Volts is turned off, disabling writing of the flash memory.
From either state 1629 or 1630 , the CPU B controller 316 proceeds to repeat the aforementioned process of monitoring for system faults (state 1602 ).
FIG. 17 is one embodiment of a flowchart showing the functions performed by the Canister controllers 324 , 326 , 328 and 330 shown in FIGS. 4 and 5. The Canister controllers 324 , 326 , 328 and 330 examine canister fan speeds, control power to the canister, and determine which canister slots contain cards. The Canister controllers 324 - 330 , starting in state 1700 , initialize their variables and stack pointers.
Next, in state 1702 the Canister controllers 324 - 330 start their main loop in which they performs various diagnostics, which are further described below. The Canister controllers 324 - 330 check the microcontroller bus 310 for a time out (state 1704 ). If the microcontroller bus 310 has timed out, the Canister controllers 324 - 330 reset the microcontroller bus 310 in state 1706 . After the Canister controller 324 - 330 reset the microcontroller bus 310 , or if the microcontroller bus 310 has not timed out, the Canister controllers 324 - 330 proceed to examine the speed of the fans (decision state 1708 ). As determined by tachometer signal lines connected through a fan multiplexer 508 (FIG. 5 ), if either of two canister fans is below the lower threshold, the event is logged, an event is sent to the System Interface 312 and, speed, in a self-management embodiment, the fan speed is set to high. The Canister controllers 324 - 330 check the fan speed again, and if they are still low the canister controlling 324 - 330 signal a fan fault and register an error message in the NVRAM 322 (state 1710 ).
If the Canister controller received a request message to turn on or off canister power, a bit would have been previously set. If the Canister controllers 324 - 330 find this bit set (state 1712 ), they turn the power to the canister on, and light the canister's LED. If the bit is cleared, power to the canister is turned off, as is the LED (state 1714 ).
Next, the Canister controllers 324 - 330 read a signal for each slot which indicates whether the slot contains an adapter (state 1716 ). The Canister controllers 324 - 330 then returns to the state 1702 , to repeat the aforementioned monitoring process.
FIG. 18 is one embodiment of a flowchart showing the functions performed by the System Recorder controller 320 . The System Recorder controller 320 maintains a system log in the NVRAM 322 . The System Recorder 320 starting in state 1800 initializes its variables and stack pointer.
Next, at state 1802 the System Recorder 320 starts its main loop in which the System Recorder 320 performs various functions, which are further described below. First, the System Recorder 320 checks the microcontroller bus 310 for a time out (state 1804 ). If the microcontroller bus 310 has timed out, the System Recorder 320 resets the microcontroller bus 310 in state 1806 . After the System Recorder 320 resets the bus, or if the microcontroller bus 310 has not timed out, the System Recorder 320 checks to see if another microcontroller had requested the System Recorder 320 to reset the NVRAM 322 (state 1808 ). If requested, the System Recorder 320 proceeds to reset all the memory in the NVRAM 322 to zero (decision state 1810 ). After resetting the NVRAM 322 , or if no microcontroller had requested such a reset, the System Recorder 320 proceeds to a get the real time clock every second from a timer chip 520 (FIG. 5A) (decision state 1812 ).
From time to time, the System Recorder 320 will be interrupted by the receipt of messages. When these messages are for storing data in the NVRAM 322 , they are carried out as they are received and the messages are stored in the NVRAM 322 . Thus, there is no state in the flow of FIG. 18 to explicitly store messages. The System Recorder then returns to the state 1802 to repeat the aforementioned monitoring process.
While the above detailed description has shown, described, and pointed out the fundamental novel features of the invention as applied to various embodiments, it will be understood that various omissions and substitutions and changes in the form and details of the system illustrated by be made by those skilled in the art, without departing from the intent of the invention.
Appendix A
Incorporation by Reference of Commonly Owned Applications
The following patent applications, commonly owned and filed Oct. 1, 1997, are hereby incorporated herein in their entirety by reference thereto:
Attorney Docket
Title
Application No.
No.
“System Architecture for Remote Access
08/942,160
MNFRAME.002A1
and Control of Environmental
Management”
“Method of Remote Access and Control of
08/942,215
MNFRAME.002A2
Environmental Management”
“ystem for Independent Powering of
08/942,410
MNFRAME.002A3
Diagnostic Processes on a Computer
System”
“Method of Independent Powering of
08/942,320
MNFRAME.002A4
Diagnostic Processes on a Computer
System”
“Diagnostic and Managing Distributed
08/942,402
MNFRAME.005A1
Processor System”
“System for Mapping Environmental
08/942,222
MNFRAME.005A3
Resources to Memory for Program Access”
“Method for Mapping Environmental
08/942,214
MNFRAME.005A4
Resources to Memory for Program Access”
“Hot Add of Devices Software
08/942,309
MNFRAME.006A1
Architecture”
“Method for The Hot Add of Devices”
08/942,306
MNFRAME.006A2
“Hot Swap of Devices Software
08/942,311
MNFRAME.006A3
Architecture”
“Method for The Hot Swap of Devices”
08/942,457
MNFRAME.006A4
“Method for the Hot Add of a Network
08/943,072
MNFRAME.006A5
Adapter on a System Including a
Dynamically Loaded Adapter Driver”
“Method for the Hot Add of a Mass
08/942,069
MNFRAME.006A6
Storage Adapter on a System Including a
Statically Loaded Adapter Driver”
“Method for the Hot Add of a Network
08/942,465
MNFRAME.006A7
Adapter on a System Including a Statically
Loaded Adapter Driver”
“Method for the Hot Add of a Mass
08/962,963
MNFRAME.006A8
Storage Adapter on a System Including a
Dynamically Loaded Adapter Driver”
“Method for the Hot Swap of a Network
08/943,078
MNFRAME.006A9
Adapter on a System Including a
Dynamically Loaded Adapter Driver”
“Method for the Hot Swap of a Mass
08/942,336
MNFRAME.006A10
Storage Adapter on a System Including a
Statically Loaded Adapter Driver”
“Method for the Hot Swap of a Network
08/942,459
MNFRAME.006A11
Adapter on a System Including a Statically
Loaded Adapter Driver”
“Method for the Hot Swap of a Mass
08/942,458
MNFRAME.006A12
Storage Adapter on a System Including a
Dynamically Loaded Adapter Driver”
“Method of Performing an Extensive
08/942,463
MNFRAME.008A
Diagnostic Test in Conjunction with a
BIOS Test Routine”
“Apparatus for Performing an Extensive
08/942,163
MNFRAME.009A
Diagnostic Test in Conjunction with a
BIOS Test Routine”
“Configuration Management Method for
08/941,268
MNFRAME.010A
Hot Adding and Hot Replacing Devices”
“Configuration Management System for
08/942,408
MNFRAME.011A
Hot Adding and Hot Replacing Devices”
“Apparatus for Interfacing Buses”
08/942,382
MNFRAME.012A
“Method for Interfacing Buses”
08/942,413
MNFRAME.013A
“Computer Fan Speed Control Device”
08/942,447
MNFRAME.016A
“Computer Fan Speed Control Method”
08/942,216
MNFRAME.017A
“System for Powering Up and Powering
08/943,076
MNFRAME.018A
Down a Server”
“Method of Powering Up and Powering
08/943,077
MNFRAME.019A
Down a Server”
“System for Resetting a Server”
08/942,333
MNFRAME.020A
“Method of Resetting a Server”
08/942,405
MNFRAME.021A
“System for Displaying Flight Recorder”
08/942,070
MNFRAME.022A
“Method of Displaying Flight Recorder”
08/942,068
MNFRAME.023A
“Synchronous Communication Interface”
08/943,355
MNFRAME.024A
“Synchronous Communication Emulation”
08/942,004
MNFRAME.025A
“Software System Facilitating the
08/942,317
MNFRAME.026A
Replacement or Insertion of Devices in a
Computer System”
“Method for Facilitating the Replacement
08/942,316
MNFRAME.027A
or Insertion of Devices in a Computer
System”
“System Management Graphical User
08/943,357
MNFRAME.028A
Interface”
“Display of System Information”
08/942,195
MNFRAME.029A
“Data Management System Supporting Hot
08/942,129
MNFRAME.030A
Plug Operations on a Computer”
“Data Management Method Supporting
08/942,124
MNFRAME.031A
Hot Plug Operations on a Computer”
“Alert Configurator and Manager”
08/942,005
MNFRAME.032A
“Managing Computer System Alerts”
08/943,356
MNFRAME.033A
“Computer Fan Speed Control System”
08/940,301
MNFRAME.034A
“Computer Fan Speed Control System
08/941,267
MNFRAME.035A
Method”
“Black Box Recorder for Information
08/942,381
MNFRAME.036A
System Events”
“Method of Recording Information System
08/942,164
MNFRAME.037A
Events”
“Method for Automatically Reporting a
08/942,168
MNFRAME.040A
System Failure in a Server”
“System for Automatically Reporting a
08/942,384
MNFRAME.041A
System Failure in a Server”
“Expansion of PCI Bus Loading Capacity”
08/942,404
MNFRAME.042A
“Method for Expanding PCI Bus Loading
08/942,223
MNFRAME.043A
Capacity”
“System for Displaying System Status”
08/942,347
MNFRAME.044A
“Method of Displaying System Status”
08/942,071
MNFRAME.045A
“Fault Tolerant Computer System”
08/942,194
MNFRAME.046A
“Method for Hot Swapping of Network
08/943,044
MNFRAME.047A
Components”
“A Method for Communicating a Software
08/942,221
MNFRAME.048A
Generated Pulse Waveform Between Two
Servers in a Network”
“A System for Communicating a Software
08/942,409
MNFRAME.049A
Generated Pulse Waveform Between Two
Servers in a Network”
“Method for Clustering Software
08/942,318
MNFRAME.050A
Applications”
“System for Clustering Software
08/942,411
MNFRAME.051A
Applications”
“Method for Automatically Configuring a
08/942,319
MNFRAME.052A
Server afier Hot Add of a Device”
“System for Automatically Configuring a
08/942,331
MNFRAME.053A
Server after Hot Add of a Device”
“Method of Automatically Configuring and
08/942,412
MNFRAME.054A
Formatting a Computer System and
Installing Software“
“System for Automatically Configuring
08/941,955
MNFRAME.055A
and Formatting a Computer System and
Installing Software”
“Determining Slot Numbers in a
08/942,462
MNFRAME.056A
Computer”
“System for Detecting Errors in a Network”
08/942,169
MNFRAME.058A
“Method of Detecting Errors in a Network”
08/940,302
MNFRAME.059A
“System for Detecting Network Errors”
08/942,407
MNFRAME.060A
“Method of Detecting Network Errors”
08/942,573
MNFRAME.061A | A network of microcontrollers for monitoring and diagnosing the environmental conditions of a computer is disclosed. The network of microcontrollers provides a management system by which computer users can accurately gauge the health of their computer. The network of microcontrollers provides users the ability to detect system fan speeds, internal temperatures and voltage levels. The invention is designed to not only be resilient to faults, but also allows for the system maintenance, modification, and growth—without downtime. Additionally, the present invention allows users to replace failed components, and add new functionality, such as new network interfaces, disk interface cards and storage, without impacting existing users. One of the primary roles of the present invention is to manage the environment without outside involvement. This self-management allows the system to continue to operate even though components have failed. | 8 |
FIELD
[0001] This disclosure relates to a control system for and method of operating a product distribution machine and is described in the context of an agricultural seeding machine.
BACKGROUND
[0002] Modern agricultural implements for sowing seed or distributing other products such as fertilizers and chemicals typically have one or more row units for distributing product in rows in a field as the implement is moved over the field. Various types of implements are known, including, but not limited to planters, drills, air seeders and nutrient applicators. Such machines are referred to herein generally as a product distribution apparatus or machine. When the distributed product is placed under the soil surface, a furrow opener is used to open a furrow into which the product is deposited. The furrow is then closed, covering the product. A typically opener is a single or double disc opener having one or two discs oriented at a slight angle to the forward direction of travel. A depth regulation member is positioned near the opener to limit the penetration of the opener into the soil to produce a furrow of the desired depth.
[0003] A downward force is needed for the opener to penetrate the soil to the desire depth. When the opener is fully penetrating the soil, the depth regulating member, often in the form of a “gauge wheel,” contacts the soil surface. The physical weight of the row unit together with the weight of any product stored on the row unit provides a downward force to help the opener penetrate the soil. However, this weight is often insufficient to ensure full penetration of the opener. It has long been the practice to provide supplemental down force to the row unit in the form of a mechanical spring arrangement. Such spring arrangements are adjustable so the operator can select a desired amount of supplemental down force before operating the implement. Changes in the amount of down force during operation is not possible.
[0004] More recently, the mechanical springs have been replaced with hydraulic or pneumatic actuators that allow the operator to make changes to the down force during machine operation. Changes are made through a control system that adjusts the hydraulic or pneumatic pressure delivered to each actuator. Even more recently, active or dynamic control of the down force is accomplished with a load sensor to measure to the soil reaction force on the depth regulation member. With dynamic control of the down force, a control system automatically operates the down force actuators by changing the system pressure in response to changing soil conditions in the field as the machine is moved over a field to achieve a desired soil reaction force on the depth regulation member.
[0005] Such active control systems can produce wide variations in the hydraulic or pneumatic pressures of the down force system as the machine moves through a field. A high capacity air compressor or hydraulic pump is needed to achieve the variation in a reasonable time. A high capacity system adds considerably to the overall cost. Large variations in the system pressures can be reduced by turning off the dynamic control of the down force for certain areas the field.
SUMMARY
[0006] A control system and method of operation of a product distribution apparatus is provided that uses map based field information to disengage the dynamic down force control for certain designated areas of the field. These areas can be roadways or waterways that are not planted with seed but through which the machine is operated. The harder soil in these areas causes the down force system to compensate by significantly increasing the pressure and thus the down force on the row unit. Once the area is crossed, and the machine returns to soil to be seeded, the down force is now much higher than needed, resulting in excessive soil compaction caused by the depth regulation member adjacent the furrow. The excessive soil compaction reduces crop yield. It may require several meters of travel before the down force can be reduced to the appropriate level.
[0007] The control system described below disengages the down force dynamic control when the designated areas are reached and leaves the down force applied by the actuator at the magnitude immediately prior to entering the area or at some other desired magnitude. This magnitude of down force will typically be much closer to the magnitude needed when the roadway, waterway or other designated area is crossed. By maintaining the down force in the designated area at the level prior to entering the area, upon exiting the area, the down force will be at a magnitude close to the desired amount.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a side view of a common row unit of a row crop planter;
[0009] FIG. 2 is a schematic view of a control system for the dynamic down force system; and
[0010] FIG. 3 is a plan view of a field map.
DETAILED DESCRIPTION
[0011] With Reference to FIG. 1 , a portion of a seeding machine 10 is shown. Seeding machine 10 is in the form of a row crop planter but may also be other forms of machines. FIG. 1 illustrates a single row unit 12 of a multi-row planter, with each row unit 12 being substantially identical and connected to a machine frame shown as a tool bar 14 . Only a single row unit 12 is shown and described below for simplicity sake.
[0012] Row unit 12 includes a row unit frame 16 which is attached to the tool bar 14 by parallel linkage 18 . Tool bar 14 in turn is coupled to a traction unit (not shown), such as an agricultural tractor. For example, the tool bar may be coupled to an agricultural tractor using a draw bar or 3-point hitch assembly. Tool bar 14 may be coupled with transport wheel assemblies, marker arms, etc. which may be of conventional design and not shown for simplicity.
[0013] Row unit frame 16 carries a double disc furrow opener 20 for forming a seed furrow 26 in soil 27 . A pair of gauge wheels 24 are provided which function as furrow depth regulation members and are respectively associated with the pair of discs of double disc furrow opener 20 . More particularly, each gauge wheel 24 is positioned generally in line with and immediately adjacent to the outside of each respective disc of double disc furrow opener 20 . The gauge wheels 24 may be vertically adjusted relative to the opener discs to adjust the depth of the furrow which is cut into the soil by the double disc furrow opener 20 .
[0014] A seed meter 32 is also carried by row unit frame 16 . Seed meter 32 receives seed from a seed hopper 28 carried above the seed meter on the frame 16 . The seed meter drive is not shown but may be of the type shown in U.S. Pat. No. 7,571,688 having a flexible cable drive with a clutch mechanism that enables the seed meter drive to be selectively disengaged to turn off the seed meter. Seed meter 32 delivers seed sequentially to a seed tube 36 through which the seed falls by gravity to the furrow 26 . The seed meter 32 and seed tube 36 form a product dispenser to dispense product to the furrow 26 . In this illustration, the product is seed but other meters can be used to dispense fertilizer, herbicides, insecticides or other chemicals.
[0015] A pair of closing wheels 38 follow behind the gauge wheels and are positioned generally in line with double disc furrow opener 20 . Closing wheels 38 are preferably biased in a downward direction and have a peripheral edge with a shape which may vary, depending upon the application. Closing wheels 38 push soil back into the furrow 26 upon the product deposited therein.
[0016] The row unit 12 is equipped with a row unit down force actuator 40 in the form of an adjustable pneumatic down force cylinder 44 . The row unit down force actuator 40 acts between the toll bar 14 and the lower links of the linkage 18 to apply down force on the row unit and the row unit components engaging the soil. The down force applied by the cylinder 44 ensures that the double disc furrow opener 20 is forming the furrow 26 to the desired depth. The down force applied to the row unit by the actuator 40 is shown by the arrow F D . The row unit weight also produces a down force shown by the arrow F G acting through the center of gravity of the row unit. The force F G varies over time as the level of product in the seed hopper 28 and chemical hopper 30 changes during operation of the machine 10 . These two downward acting forces, F D and F G are counter-acted by upward forces acting on the row unit. The opener penetrates the soil and has a force F O acting upward on the opener. When the opener 20 is fully penetrating, the gauge wheels 24 will be in contact with the soil and a soil reaction force F R acts upward on the gauge wheels. An additional upward force on the row unit includes the force F C acting on the closing wheels 38 .
[0017] A minimum soil reaction force F R is desired to ensure that the opener is fully penetrating the soil to the desired depth. If the opener is not fully penetrating, the gauge wheels will not touch the soil and F R will be zero. Thus, some level of force F R greater than zero is desired to ensure there is full penetration. The magnitude of the force F R can be measured by a sensor or load cell in a variety of locations on the row unit. One example is a load sensing pin 46 in the gauge wheel depth adjustment link 48 . Adjustment link 48 bears against and resists upward movement of the pivot arm 50 supporting the gauge wheels 24 . A suitable load sensing pin is shown in WO2008/086283 A2. A controller 52 of a control system 54 receives a sensor output signal from the load sensing pin 46 and controls the pressure in the cylinder 44 accordingly to achieve the desired soil reaction force F R on the gauge wheels.
[0018] As the machine 10 is moved through a field, the soil conditions will not be constant. In some areas of the field, the soil will be harder than in other areas. When the soil is harder, the force F O required for full opener penetration will increase. If the down force F D applied to the row unit remains constant, the soil reaction force F R and the closing wheel force F C will decrease and possibly go to zero. To avoid this, the controller 52 dynamically or actively monitors the output of the sensor 46 . As the force F R decreases, with harder soil, the controller will operate the actuator 40 to increase the down force E D acting on the row unit to maintain the desired force F R on the gauge wheels. Likewise, if the force F R increases, with softer soil, the controller 52 will operate the actuator 40 to reduce the down force F D . Operation of the actuator 40 is accomplished by commanding a change in the air pressure for the pneumatic down force cylinder 44 . The associated air compressor and valves are not shown but are well known. Hydraulic or electrical actuators could also be used to apply the down force F D and are actuated to very the down force F D .
[0019] While the row unit 12 is shown with the sensor 46 , it is possible to use one sensor 46 on one row unit to measure the force F R on the gauge wheels of that row unit while the controller receiving the sensor 46 output signal then controls the actuators 40 of multiple row units. This reduces the control system complexity and cost. Some machines may be configured with multiple row units carried as a gang on a movable frame. With such an arrangement, a single actuator 40 can apply down force to multiple row units. All such variations in the configuration of the machine 10 are contemplated in the following claims.
[0020] Large fluctuations in the soil hardness will require a longer time for the control system to adjust and change the down force F D . The length of time is a function of the system capacity, such as the air compressor used to supply pneumatic pressure to the cylinder 44 . One way to reduce the adjustment time is to increase the system capacity. This also increases the system cost. Some fluctuations in the down force can be anticipated and planned for based on an electronic field map. With reference to FIG. 3 , a map 60 of a portion of a field 62 is shown. The field includes first areas 64 that are to be seeded or have other products applied thereto. Cutting through the field is a second field area shown as a waterway 66 . Waterway 66 is typically covered in a perennial grass to avoid or reduce erosion from the field. The soil in the waterway is typically much harder than the soil in the first field areas 64 . When a row unit enters the waterway, the force, F O , on the opener to achieve full penetration will dramatically increase, and the soil reaction force F R on the gauge wheels will decrease. This results in the controller commanding an increase in the down force F D to return the soil reaction force F R to the desired magnitude. When the row unit then returns to the first area 64 , the down force F D is much higher than needed, resulting in undesirable compaction of the soil adjacent the furrow 26 . The machine may have to travel several meters before the system reaches the desired lower down force F D . Since the waterway is not used to produce a crop, proper penetration of the opener 20 is not required in the waterway 66 .
[0021] To avoid the large fluctuations in the down force F D , the control system is programmed to not operate the actuator 40 while the row unit is in the waterway. By not operating the actuator, it is meant that the system pressure is not changed and a constant magnitude of down force is maintained. This is accomplished by including in the control system 54 a memory with an electronic field map 60 ( FIG. 3 ) with the location of the first field areas 64 and second field area 66 identified. The memory with the field map is accessible by the controller 52 . In addition, the control system 54 includes a machine locating system 68 such as a satellite based global positioning system or a local positioning system. The locating system provides an output to the controller indicative of the machine location to enable the controller to determine the location of the machine in the field. In FIG. 3 , the machine 10 shown by the tool bar 14 and row units 12 is about to move from the first field area 64 into the second field area 66 . When the row unit exits the first field area 64 and enters the second field area 66 , the controller no longer operates the actuator 40 and instead leaves the actuator at the pressure and down force F D that existed immediately prior to exiting the first area 64 . Then, when the row unit returns to the first field area 64 after crossing the waterway 66 , the dynamic control of the down force F D resumes at a pressure likely close to the needed pressure to produce the desired soil reaction force F R on the gauge wheels 24 . Switching on and off of the dynamic control of the down force can be done on individual row units at a time, a section of row units at a time or on all row units of the machine at a time.
[0022] As an alternative, the control system may be programmed to produce a different desired soil reaction force F R1 while in the second field area. The desired and thus commanded force F R1 in the waterway may be a lesser force than F R to reduce wear on the row unit while traveling through the waterway. As a further alternative, the control system can be programmed such that, while in the waterway, as the row unit approaches the first field area 64 , the system pressure changes from that needed to produce a soil reaction force of F R1 in the waterway to the pressure previously needed to produce a soil reaction force of F R in the first field area. Then, upon returning to the first field area, the pressure the pneumatic system is close to the needed pressure to produce the desired reaction force F R . This results in a relatively short time and travel distance needed to achieve the desired soil reaction force F R once the row unit returns to the first field area and dynamic control of the down force is resumed.
[0023] Returning once again to FIG. 1 , the seed meter 32 and the seed tube 36 constitute a produce dispenser 70 as that term is used in the following claims. The controller 52 also controls operation of the dispenser 70 , by controlling the operation of the seed meter through the clutch mechanism previously described. (In some machines, operation of the dispenser is controlled through valves or gates to stop the flow of product rather than by stopping the meter drive mechanism.) In many instances, it will be desired to cease operating the dispenser 70 when the row unit is in the second field area. In such a case, the controller 52 may cease operating the dispenser 70 and cease the dynamic control of the actuator 40 simultaneously when entering the second field area. Operation of the dispenser is then resumed simultaneously with resuming dynamic control of the down force actuator upon return to the first field area.
[0024] In some machine forms, such as an air seeder, the seed meter is located remotely from the row unit and furrow opener. A lengthy pneumatic distribution system delivers seed from the meter to the furrow. In such a machine, the seed meter and distribution system form the product dispenser, which still terminates in a tube delivering product to the furrow. With such a machine, the control system 54 will still operate both the product dispenser and the down force actuator 40 . But when approaching waterway 66 , the dispenser will be shut-off before the waterway is entered allowing the product in the pneumatic distribution system to be dispensed prior to reaching the waterway. When the waterway is reached, the dynamic control of the actuator 40 is ceased. Prior to return to the first field area, the product dispenser is activated to fill the distribution system by the time the row unit reaches the first field area. The dynamic control of the down force actuator resumes upon returning to the first field area.
[0025] Depending on the farming practice, the dispensers may or may not be operated in the waterway. Paths or roadways cutting across the field are other types of field areas for which it may be desirable to stop the dynamic operation of the down force actuator 40 .
[0026] Having described the control system and method, it will become apparent that various modifications can be made without departing from the scope of the accompanying claims. | A control system and method of operation of a product distribution apparatus or machine that uses map based information to disengage the dynamic down force control for certain designated areas of the field. These areas can be roadways or waterways that are not planted with seed but through which the machine does operate. The control system disengages the down force dynamic control when the designated areas are reached and leaves the down force applied by the actuator at the magnitude immediately prior to entering the area or at some other desired level. This magnitude of down force will typically be much closer to the magnitude needed when the roadway, waterway or other designated area has been crossed. | 0 |
BACKGROUND OF THE INVENTION
[0001] I. Field of the Invention
[0002] This invention relates generally to high speed metal punching equipment suited for installation in a turret-style punch press and more particularly to the design of a punch assembly used in such equipment that allows for quick removal of a worn punch insert from the punch guide for refurbishment and return or replacement.
[0003] II. Discussion of the Prior Art
[0004] To provide increased mean-time-to-repair of punch assemblies used in high-speed CNC controlled turret punch presses, it has proved expedient to employ a high-grade high speed steel insert such as American National Standards Institute M2 steel punch point insert affixed to the end of a lower cost steel punch driver to reduce cost of the punch press assembly. Notwithstanding the use of such a high-grade and relatively expensive punch point insert, after a period of use in punching holes through sheet steel and other metals, it becomes necessary to replace the punch point insert with a new or resharpened one. To reduce the downtime of the turret punch press for such punch point insert replacement, it is desirable that an operator be able to perform this task in a minimum amount of time and most preferably without the need for special hand tools.
[0005] In prior art punch assemblies having a two-piece driver/insert combination, it has generally been necessary to first remove the punch driver and insert from the upper end of the punch guide and subsequently remove the punch insert from the punch driver so that the punch point insert can be replaced with a new or refurbished unit. The present invention makes possible reduced manufacturing costs, such as machining expenses e.g. through the use of stamped components while at the same time simplifying punch point replacement by providing a way to releasably clamp the stripper member to the end of the punch guide and the punch point insert to the punch driver. The clamping mechanism employed is most preferably actuated by hand and in most cases without the need for any special tools or without the need to remove the punch driver and insert from the punch guide.
SUMMARY OF THE INVENTION
[0006] The present invention provides a punch assembly for a turret punch press comprising an outer, generally cylindrical punch guide having a cylindrical bore extending longitudinally therethrough from an upper end to a lower end. Contained within the bore of the guide or housing is a punch driver that is reciprocally movable within the bore. Releasably affixed to the lower end of the punch driver, preferably by one or more flexible stamping elements, is a punch insert having a punch point of a predetermined shape at a lower end thereof.
[0007] Affixed to the upper end of the punch driver is a canister assembly which includes a cylindrical, tubular housing containing a compression spring for normally biasing the punch driver to a retracted disposition within the bore.
[0008] Formed inward from a peripheral surface of the generally cylindrical punch driver and extending longitudinally are a plurality of guideways in which are fitted a corresponding plurality of locking sliders which can be stampings shaped to engage the punch insert and lock same to the punch driver when the locking sliders are in a first disposition within the guideways and to disengage from the punch insert when in a second disposition within the guideways. Cooperating with the plurality of locking sliders is a lock collar that is concentrically disposed on the punch driver and rotatable through a predetermined arc between a locked disposition and an unlocked disposition relative to the locking sliders.
[0009] The stripper member for the punch assembly, which itself can be a metal stamping of substantially uniform thickness throughout, is releasably clamped to the punch guide at a lower end thereof most preferably by leaf spring elements, and it includes an aperture conforming in shape to the punch point of the punch insert allowing the punch point to extend through the aperture in the stripper member upon application of a force to the canister assembly that exceeds the return force offered by the compression spring. The clamping structure holding the stripper member to the bottom of the punch press guide is also manually actuatable without the need for any special tools to unclamp and reclamp the stripper member from and onto the punch guide.
DESCRIPTION OF THE DRAWINGS
[0010] The foregoing features, objects and advantages of the invention will become apparent to those skilled in the art from the following detailed description of a preferred embodiment especially when considered in conjunction with the accompanying drawings in which like numerals in the several views refer to corresponding parts.
[0011] FIG. 1 is an isometric view of a preferred embodiment of a punch assembly from a high speed turret punch constructed in accordance with the present invention;
[0012] FIG. 2 is an isometric view as in FIG. 1 but with the outer punch guide removed;
[0013] FIG. 3 is an exploded perspective view showing the manner of attachment of the punch canister to the punch driver;
[0014] FIG. 4 is a perspective view shown with the canister cover and return spring removed to better illustrate the mode of attachment of the canister assembly with a punch driver.
[0015] FIG. 5 is a detailed perspective view of the structure releasably securing the punch insert to the punch driver;
[0016] FIG. 5A is a horizontal cross-section taken on line 5 A- 5 A of FIG. 5 ;
[0017] FIG. 6 is a view like that of FIG. 5 , but with the lock collar, retaining ring and centering collar removed to show underlying parts;
[0018] FIG. 6A is a rear perspective view of a vertical slider strip component;
[0019] FIGS. 7A-7D , respectively, show a perspective view, a side view, a top view and a bottom view of the punch insert with FIG. 7C also showing the position of alignment strap 48 ;
[0020] FIG. 8 is a cross sectional view of the embodiment of FIG. 1 taken along the XY plane;
[0021] FIG. 9 is a cross sectional view of the embodiment of FIG. 1 taken along the YZ plane;
[0022] FIG. 10 is an enlarged detail view of the lower end of FIG. 9 ;
[0023] FIG. 11 is a detailed view showing the placement of the cone collar; and
[0024] FIG. 12 is a perspective view of the cone collar component.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0025] This description of the preferred embodiments is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description of this invention. In the description, relative terms such as “lower”, “upper”, “horizontal”, “vertical”, “above”, “below”, “up”, “down”, “top” and “bottom” as well as derivatives thereof (e.g., “horizontally”, “downwardly”, “upwardly”, etc.) should be construed to refer to the orientation as then described or as shown in the drawings under discussion. These relative terms are for convenience of description and do not require that the apparatus be constructed or operated in a particular orientation. Terms such as “connected”, “connecting”, “attached”, “attaching”, “join” and “joining” are used interchangeably and refer to one structure or surface being secured to another structure or surface or integrally fabricated in one piece, unless expressively described otherwise.
[0026] As shown in FIG. 1 , the punch assembly is indicated generally by numeral 10 . It comprises an outer, generally cylindrical punch guide 12 which, as shown in the cross-sectional views of FIGS. 8-10 , includes a cylindrical bore 14 that extends longitudinally therethrough from the guide's upper end 16 toward, but short of its lower end 18 . A counter bore 19 of a slightly greater diameter than that of bore 14 extends inward from the lower end 18 as can be seen in FIG. 9 .
[0027] Releasably secured to the lower end 18 of the punch guide 12 is a stripper member 20 in the form of a generally circular plate which can be a metal stamping of substantially uniform thickness throughout that requires minimal machining and has a central aperture 22 conforming in shape to that of a punch point 24 , as can be best seen in the enlarged cross-sectional view of FIG. 10 .
[0028] As seen in FIG. 2 , the stripper member 20 has an annular sidewall provided with a plurality of regularly spaced upwardly extending tabs 26 formed around the periphery thereof that are adapted to fit into a corresponding pattern of recesses formed in the bottom end 18 of the guide 12 and to be engaged by a pair of leaf spring retainer clips 28 which can be metal stampings that fit into recesses 30 that are machined into the sidewall of the guide 12 . Only one such recess is visible in the view of FIG. 1 , the other being on a diametrically opposed location as depicted in the cross-sectional view of FIG. 8 . The configuration of the leaf spring retainer clip is such that depression of a pad portion thereof, identified by numeral 32 in FIG. 1 , further into the recess 30 will cause the lower end thereof that engages the tabs 26 to deflect radially outward so as to no longer engage the tabs and allows the stripper member 20 to be removed from the bottom end 18 of the punch guide 12 .
[0029] Referring again to the cross-sectional views of FIGS. 8-10 , there is disposed within the longitudinal bore 14 and counter bore 19 of the punch guide a two-piece, reciprocally movable combination of a punch driver 34 in its cooperative relationship with the punch point insert 24 . The punch driver 34 is preferably formed from relatively low-cost steel while the punch point insert 24 , preferably fabricated from high grade steel such as powdered metal or tungsten carbide that is pressed, formed or machined into a desired shape. While a tungsten carbide insert increases the cost, because it is approximately three times stiffer than steel and is much denser than steel or titanium, it makes for a longer wearing tool that is highly abrasion resistant and capable of withstanding higher temperatures than standard high speed steel tools. It is also well recognized that tungsten carbide is capable of maintaining a sharp cutting edge in a way that is superior to other tools.
[0030] The shape configuration of the punch point insert can be discerned from the views of FIGS. 7A-7D . Here, the punch point insert is illustrated as a rectangular edge and will produce a rectangular slug upon being made to descend through a sheet metal workpiece. Of course, other shapes are achievable by modifying the shape of the downwardly depending portion 38 of the punch point insert 24 .
[0031] In FIGS. 7B and 7C , the punch point insert is shown to have a generally rectangular head portion 40 , but with radiused corners, and projecting upwardly therefrom is a somewhat diamond-shaped protuberance 42 that is designed to fit within a recess 44 formed in the bottom surface of the punch driver as best seen in the enlarged cross-sectional view of FIG. 10 . If desired, the protuberance can be on the punch driver and the recess in the insert. To maintain a desired angular orientation between the punch point insert 24 and the punch driver 34 , a longitudinally extending groove 46 is formed inward from the peripheral surface of the punch driver as seen in FIG. 3 , and fitted into this groove is a leaf spring alignment strap 48 having a notch 50 that is arranged to straddle the tapered protuberance 42 ( FIG. 7C ) and apply a centrally directed bending force for yieldably engaging punch point ramp surfaces 42 a and 42 b which are slanted relative to one another so as to maintain the desired exact rotative registration of the insert about a vertical axis with no clearance unlike an ordinary pin or key which require clearance.
[0032] With continued reference to the exploded view of FIG. 3 , the punch driver 34 has opposed flat abutment surfaces 52 and 54 machined therein on which a canister assembly, indicated generally by numeral 56 , is adapted to be secured. With reference to FIGS. 2-4 , the canister assembly is seen to comprise a cylindrical, tubular housing 58 having an inside diameter that is sized to fit over the outer diameter of a relatively stiff compression spring 60 . Fitted atop the cylindrical housing 58 is a punch head 62 that has a pair of spaced-apart, downwardly depending legs 64 , 66 where the legs terminate in transversely extending feet 68 as shown. The canister assembly further includes a spring retainer plate 70 consisting of a circular plate having a central aperture 72 . Fitted through the aperture 72 is a pair of couplers 74 and 76 that are generally U-shaped, with the legs of the “U” extending upwardly as seen in FIG. 4 and also having feet that are designed to engage the feet 68 on the legs 64 and 66 that are integrally formed with and project downward from the punch head 62 . The spring retainer plate 70 is designed to rest upon the upper end of the punch guide 12 , as seen in FIG. 1 . Couplers 74 and 76 slide in and out radially in retainer plate 70 aperture to allow for assembly with punch head 62 . When so positioned, the flattened portions 52 and 54 of the punch driver 34 above the shoulder 78 fit between the couplers 74 and 76 thereby locking them radially outward to maintain engagement with punch head 62 feet 68 . A flathead cap screw 80 fits through an aperture in the punch head 62 and is screwed into a threaded bore 82 formed inward from the top surface of the punch driver 34 .
[0033] From what is described, it can be recognized that a mechanical or electro mechanical ram forming part of the turret punch imparts a downward force on the punch head 62 , it will drive the punch driver 34 downward through the aperture in the spring retainer plate 70 of the canister by a distance, D, shown in FIG. 4 and which is sufficient to penetrate through a sheet metal workpiece positioned adjacent the stripper member 20 . When this driving force is removed, the return spring 60 acting between the spring retainer plate 70 and the punch head 62 will function to move the punch driver 34 in the upwards direction such that the punch point insert will no longer extend through the aperture 22 in the stripper member 20 .
[0034] Without limitation, the return spring 60 follows Hook's Law for springs.
[0035] Next to be described is the structure for releasably securing the punch point insert 24 to the punch point driver 34 and, in this regard, reference will be made primarily to FIGS. 5 , 6 and 8 - 10 of the drawings.
[0036] Referring now to the enlarged partial view of FIG. 5 and cross-sectional view of FIG. 5A , there are formed inward from the cylindrical surface of the punch driver 34 four guideways, as at 84 , milled or ground at 90° radial spacings thereabout. These four grooved guideways are adapted to receive four vertical slider strips which can be metal stampings that require little machining, two of which are visible in the view of FIG. 6 and are identified by numerals 86 . The exposed surface thereof as seen in FIG. 6 is slightly rounded so as to conform to the cylindrical profile of the punch driver 34 and includes a flat facing zone 88 that extends about half of the distance across the width dimension of the vertical slider strip and a raised zone 90 extending across the remaining half of the strip's width dimension. Formed in the raised zone 90 is a notched-out portion 92 . FIG. 6A is a rear perspective view of the vertical slider strip 86 and it is configured to exhibit a notched-out region 94 adapted to fit about the head portion 40 of the punch point insert 24 in the manner shown in FIG. 6 .
[0037] Each of the slider strips 86 has associated with it a cylindrical pin as at 96 . The inner ends of these pins are adapted to contact either the flat portion 88 of the slider strip or the notched-out portion 92 thereof. As seen in FIGS. 5 and 5A , the pins 96 fit into apertures formed radially through a toroidal lock collar 98 that is supported by an annular, C-shaped retaining ring 100 designed to reside in the annular groove 102 formed in the punch driver 34 as seen in FIG. 6 . The retaining ring 100 prevents the lock collar 98 from moving longitudinally downward along the punch driver.
[0038] From the drawings of FIGS. 5 , 5 A and 6 , it can be appreciated that when the locking collar is rotated about a vertical axis, the pins 96 may be repositioned so as to either reside on the flat surface 88 or have its end disposed in the notched-out portion 92 of the vertical slider strip. With the pins 96 residing on the flat portion 88 , as the punch point insert 24 is manually pulled downward, the vertical slide strip is able to move with it to the point where the notched-out region 94 on the back surface of the strip 86 no longer locks to the insert and it can be pulled free of the punch point driver 34 . However, when the locking collar is rotated manually, e.g. through a port 99 in the guide 12 ( FIG. 1 ) so as to reside in the notched-out portion 92 , the vertical slider strip is unable to be displaced within its slot 84 and the notched-out portion 94 continues to lock the punch point insert 24 to the bottom surface of the driver 34 .
[0039] Hidden from view in FIG. 5 by a centering collar 104 , but visible in the partial view of FIG. 11 , is a cone collar 106 that is shown by itself in FIG. 12 . As seen in FIGS. 11 and 12 , the cone collar 106 is machined so as to have an upper ring portion 108 with four downwardly projecting and inwardly tapered teeth 110 and when assembled onto the punch driver 34 in surrounding relationship with respect to the four slider strips 86 , the teeth are seen to fall between adjacent ones of the strips 86 and rest upon the inside conical surface of the centering collar 104 . The cone collar 106 and the centering collar 104 work together to create a high precision centering feature. The centering collar 104 has a precision cylindrical fit with respect to the cone collar 106 and the cone collar itself has a precision cylindrical fit with the punch driver 34 which, in turn, has a precision cylindrical fit with the ID of the bore 14 of the punch guide 12 . In addition, the slide strips 86 are forced outward on the bottom end due to the ramping action caused by the sliders 86 notched-out portion 94 against angled ramps # 95 ( FIG. 10 ) on insert 24 as collar 98 is rotated such that pins 96 enter area 92 against ramping edge # 97 ( FIG. 6 ) on sliders 86 to securely hold punch insert and sliders in the up position. To provide extremely precise centering, the outward force of the ramps is further advantaged, by pressing outwardly against the centering collar 104 . The circular area on the perimeter of the centering collar not being pushed against by the sliders then react equally and opposite thus sway inwardly against the cone collar. This provides a precise centering mechanism not achievable with normal bore and shaft connections.
[0040] In that the stripper 20 is stamped with curled-up fingers 26 for positioning into the punch guide, it is designed such that the operator can remove the stripper before the punch insert is removed, thus obviating the need for the operator to pull the canister assembly 56 off the punch guide as required by known prior art designs just to change the punch insert.
[0041] This invention has been described herein in considerable detail in order to comply with the patent statutes and to provide those skilled in the art with the information needed to apply the novel principles and to construct and use such specialized components as are required. However, it is to be understood that the invention can be carried out by specifically different equipment and devices, and that various modifications, both as to the equipment and operating procedures, can be accomplished without departing from the scope of the invention itself. | A punch assembly for a turret punch press having a two piece reciprocally movable punch member that has a punch point insert removably attached to a punch driver that allows replacement of the punch point insert without the need to extract the punch member from its punch guide. A locking assembly comprising four vertical guideways containing slider strips for coupling the punch point insert to the punch driver ensures precision registration of the punch point insert with its driver. | 8 |
BACKGROUND OF THE INVENTION
This invention relates to a device for improving the air supply for internal combustion engines that are typically used in automotive vehicles.
Applicant is unaware of any device which can be easily and inexpensively attached to the housing of a conventional air filter associated with a typical vehicular internal combustion engine to significantly improve the output power and curtail harmful emissions by forcing a greater quantity of cool air into the engine than normally asperiated thereby.
It is well known in the art to supplement the air drawn into an internal combustion during normal operation by providing a separately driven blower which forces air, preheated by the heat of the engine, through an air filter located across the air intake of the engine to thereby increase its output power. U.S. Pat. No. 1,995,935 discloses the use of a centrifugal fan type blower which has its rotor attached directly to the crankshaft of the engine and forces air to both the cylinder walls as well as the intake of the carburetor to boost the engine's power. Such a system is too complex and would be totally impractical, if not impossible, to install on an engine of an present day automobile after its manufacture by one of average mechanical skill. U.S. Pat. No. 2,681,646 discloses a blower of the propeller type connected through a funnel shaped duct to the side of an internal combustion engine air filter housing. The propeller is rotated by a driving wheel in frictional engagement with the engine cooling fan belt. The air flow capable of being generated by a propeller fan of this nature and relative size would not appear to be capable of significantly increasing the output of an internal combustion found in present day automobiles. Nor would driving the propeller by the cooling fan belt be easily or relatively inexpensively accomplished by one of general mechanical skill due to the great variety of complex belt arrangements encountered on present day vehicular engines.
In contrast to the supplemental air systems of the prior art, a few of which were above described, applicant's invention has as its principal object the provision of a compact, relatively inexpensive electric motor driven centrifugal fan type blower which can be easily installed on any present day internal combustion engine located in a vehicle by one housing general mechanical skill.
It is another object of the present invention to provide a supplemental air system in the form of a blower which may be connected to the housing of an air filter without changing or replacing any of the engine parts on old or existing automotive engines.
It is a further object of the present invention to provide a device of the above mentioned character that will effect a substantial fuel economy, improved horsepower and reduced undesirable hydrocarbon emissions as a result of the increased quantity of air entering the carburetor.
It is still another object of the present invention to provide a device of the class described which includes a means for automatically selecting air from a source which has not been preheated and is cool relative to that air in the compartment enclosing the engine during normal operation.
It is yet another object of the present invention to provide a device of the class described which can be provided with either manual or accelerator actuated control and which is simple in its construction, compact, and comparatively economical in its manufacture, installation, operation and maintenance.
Other objects and advantages of my invention will be apparent during the course of the following description.
In the drawing forming a part of this specification and wherein like numerals and other characters of reference are employed to designate like parts throughout the same.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a side elevation of a device embodying my invention and showing the same associated with the air filter of an automotive vehicle;
FIG. 2 is a cross-sectional view taken along lines 2--2 of FIG. 1; and
FIG. 3 is a schematic of a wiring diagram.
DETAILED DESCRIPTION OF INVENTION
Referring in detail to the drawing, 10 denotes an air cleaner of conventional construction having a lower housing portion 12 with an outlet 14. As shown in this embodiment of the invention, the outlet 14 is connected to the air inlet of a carburetor 16 connected to an internal combustion engine 18 of the gasoline type having a radiator 19. It being understood, of course, that the outlet 14 could as well be secured to the air inlet of a gasoline or diesel fuel injected engine. The air cleaner 10 also has a filter element 20 which is typically round and is located within the lower housing portion 12 and beneath a top or lid 22.
Prior to the installation of applicant's invention, the typical air cleaner 10 would be provided with a longitudinal opening 24 at which is attached a funnel-shaped air intake tube (not shown) extending from the opening 24 a distance into the engine compartment 26. On existing motor vehicles, the aforementioned air intake tube would be removed leaving only the opening 24 to enable air to enter the air cleaner 10. Heretofore, if the air intake tube was short, air in the compartment 26 preheated by the engine was drawn into the carburetor which was extremely hot particularly when stopped in traffic during the summer months or in warmer locations. Asperation by the engine of this hot air resulted in inefficient combustion of the fuel-air mixture with the resultant loss of power and increase in the discharge of harmful exhaust emission as well as an increase in the operating temperature of the engine. These undesireable operating conditions were not satisfactorily overcome by extending the air intake tube a distance to a location of unpreheated air because the friction resulting from the increased length of the tube resulted in a decrease in the amount of air actually reaching the engine thus having an undesirable effect on the operation of the engine.
To overcome the aforementioned differences in the systems of the prior art as above discussed, applicant provides a blower 30 having a centrifugal fan 32 rotatably mounted within a housing 34. The housing has an opening 36 which is aligned with the opening 24 in the air cleaner housing 12 and the blower is secured to the housing 12 by pivotable fasteners 33. The blower fan 32 is driven by an electric motor 38 in a manner to bae further described later. It is sufficient to say at this point that rapid rotation of the fan 32 draws air in large quantities through inlet 40 of the blower 30 and from there into the air cleaner 10 through opening 24. The inlet 40 is connected to the outlet side 42 of a two way air control valve 44 by conduit 45. A first inlet 46 of the control valve 44 has a conduit 47 connected thereto at one end 48 thereof, the other end 50 extending to an area outside of the engine compartment 26 whereby air unheated by the engine 18 will be drawn through the conduit 46 by the blower 30 when the control valve 44 is in a first position. A second inlet 52 of the control valve 44 has a conduit 54 connected thereto at one end 56 thereof, the other end 58 being connected to a heat exchanger 60. The heat exchanger 60 utilized the heat radiating from the engine exhaust manifold 62 to warm air drawn through it by the blower 30 when the control valve 44 is in a second position.
Typically, the control valve 44 would have a valve head 64 (see phantom lines) movable between the aforementioned first and second positions by means of a vacuum actuated valve head control mechanism 66. The mechanism 66 is connected to a source of vacuum at the carburetor 16 by means of tubing 68 by way of a thermostatically controlled valve 70 located in the lower housing portion 12. When the engine is cold such as initial starting, the valve 70 is actuated by the temperature of the cold air in the space 72 to the open position thereby permitting the vacuum from the carburetor to move the mechanism 66 and valvehead 64 such that preheated air from the heat exchanger 60 is forced into the engine 18 by the blower 30. This ensures a more rapid warmup of the engine 18 with a resultant reduction in the discharge of harmful emissions. Upon the engine reaching its operating temperature, the valve 70 would permit the mechanism 66 and valvehead 64 to permit air to be drawn into the engine 18 through conduit 47 by blower 30.
Referring now to FIG. 3, an electric control circuit is disclosed for the electric motor 38 which shows the motor 38 connected in series with the vehicle's battery 74. For strictly manual control of the speed of the motor 38, a variable resistance 76 is also connected in series with the battery 74 and motor 38. As the resistance 76 is increased by movement of a lever 78, the speed of the motor 38 is reduced in a well known manner. If it is desired to control the speed of the motor 38 as the throttle (not shown) of the carburetor 16 is opened, the lever 78 can be moved to a position (A) which cuts out the resistance 76 but connects in series with the motor 38 and battery 74, a second variable resistance 80. The resistance across the variable resistance 80 is adjustable by means of a lever 82 operatively connected to the linkage 84 from the throttle (not shown) to the accelerator pedal 86. Thus, as can be seen, the speed of the blower 30 and the air fed to the carburetor 16 of the engine can be manually controlled by lever 78 or by lever 82 and accelerator pedal 86. To insure that the blower 30 operates only after the engine 18 has reached the desired temperature, a thermostatically actuated switch 88 can be placed in series with the battery 74. The switch 88 would have a sensing element 90 in contact with the engine 18 itself or in the water coolout system (not shown).
It is to be understood that the form of my invention, herewith shown and described, is to be taken as a preferred example of the same and that various changes in the size, shape and arrangement of parts may be resorted to without departing from the spirit of my invention, or scope of the appended claims. | An air charging system for an internal combustion engine is disclosed which includes an electric motor driven blower mounted on the air cleaner housing located at the air intake of either a carbureted or fuel injected engine. The blower forces either heated air during startup or unheated air during actual running to the engine to thereby boost the output power and reduce harmful emissions. The speed of the blower can be either manually controlled or controlled in conjunction with actuation of the engine's throttle. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to spindle motors and, more particularly, to a spindle motor having unitized components so that faulty components can be replaced and modification can be made without replacing the entire spindle motor or discarding useable components.
2. Background Information
In the related-art spindle motors to be built into various apparatuses including hard disc drive apparatuses, there is known a structure having a rotor hub and sleeve that are combined by arranging a shaft on a motor frame or a structure having a rotor hub and shaft that are combined by attaching a sleeve onto a motor frame (e.g. Japanese Patent Laid-Open No. 245427/1994).
Also, there is adopted a structure for a spindle motor by directly assembling on an apparatus a ball bearing or bearing as a part of the motor.
In the former structure, however, there has been a problem that if the motor assembled upon manufacture becomes faulty, it must be scrapped entirely. There has arisen another problem that, where there are diversified specifications, the number of parts has to be increased on a model-by-model basis.
In the latter structure, on the other hand, the parts are directly assembled into the apparatus and hence some motor parts are integrated with the mating apparatus structure in order to reduce the apparatus size. However, when there occurs faulty in the apparatus, the apparatus as a whole has to be scrapped causing an increase in cost.
It is therefore an object of the present invention to provide a spindle motor which is capable of solving the problems as encountered in the related art.
SUMMARY OF THE INVENTION
In order to solve the foregoing problems in the conventional art, the present invention provides a spindle motor comprising a sleeve fixed in a base; a bearing section rotatably accommodated and held in the sleeve; a shaft section attached to the bearing section; a hub attached co the shaft; a rotor magnet mounted on the hub; a stator coil arranged close to the rotor magnet; and wherein at least one portion is included which is made as a unit formed by two and more of the constituent elements. This enables checking on a unit-by-unit basis during manufacture. It there is an unacceptable unit, it is satisfactory to merely scrap the sane unit. In a case that some parts require modification due to diversification of specifications, the unitized common parts can be still used without change, making it unnecessary to increase parts for each model.
Also, such unitization makes it possible to cope with an unacceptable unit by merely removing it. Thus, cost reduction is to be expected.
In this manner, parts can be made common for all the models, resulting in cost reduction. Furthermore, even where it is built in an apparatus and thereafter becomes poor, the apparatus and its parts can be reusable.
According to the invention, there is provided a spindle motor, further comprising: the base; a stator coil arranged in the base; a sleeve-and-bearing unit formed by attaching the bearing in the sleeve arranged in a center position of the base; and a rotor unit having a shaft section arranged in the bearing section and an inner peripheral surface mounted with the rotor magnet opposed to the stator coil.
The base may be exclusive one prepared for the spindle motor. Alternatively, it is possible to utilize as the base one part of a frame of an apparatus on which the spindle motor is to be mounted.
In the invention, an adhesive groove can be provided in an outer peripheral surface of the sleeve to hold an adhesive for fixing the sleeve to the base, and the sleeve at the outer peripheral surface being fixed to the base through the adhesive.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a frictional force to be applied to the shaft section at a start and stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve being formed of a stainless based metal material.
The bearing section is formed by a fluid dynamic pressure bearing.
Also in this case, the shaft section has a tip formed by a convex spherical surface to thereby reduce a frictional force to be applied to the shaft section at a start and stop of the motor.
Furthermore, the bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve being formed of a stainless based metal material.
The bearing section may have a vertical circulatory groove provided in an inner peripheral surface thereof to enable a dynamic pressure producing liquid to be circulated around the bearing section.
A space may be formed by the shaft section, the bearing section and the sleeve to collect a dynamic pressure fluid, thereby smoothing the supply of a dynamic pressure fluid.
A radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove be formed in at least one side surface of the bearing section. With this structure, the dynamic pressure producing grooves may be satisfactorily formed only in the surface of the bearing section, thus facilitating forming and hence improving forming efficiency.
Also, a radial dynamic pressure groove may be formed in an outer peripheral surface of the bearing section and thrust dynamic pressure producing grooves may be formed in respective side surfaces.
The sleeve may be in a cap form, and the bearing section in the sleeve being rotatably held in the sleeve by an annular pressing member press-fitted in the sleeve.
In this case, the sleeve has an inner peripheral surface end edge projecting greater than the pressing member to thereby form an adhesive reservoir close to the inner peripheral surface end edge of the sleeve, preventing the adhesive from flowing to an outside.
The base and the rotor unit at an outer peripheral edge may form an opposed portion, and a labyrinth is formed in the opposed portion. In the event that dusts, such as magnetic particles or oil mist, accumulate at an inside portion, the above structure can prevent the magnetic particles and dusts from being discharged to an outside. This is very effective if applied for a hard disc drive apparatus.
A wide annular groove may be circumferentially formed in an outer peripheral surface of the sleeve, and the sleeve being press-fitted in a fitting hole opened correspondingly in the base to the sleeve thereby fixing the sleeve to the base. Fixing is possible without using an adhesive, improving operationality.
The annular groove may be also utilized as an adhesive groove, and the sleeve being fixed to the base using both press-fit and adhesion, thereby providing further firm fixing.
The annular groove may be formed in a corresponding position to the bearing section, thereby preventing a deforming stress to be applied to the bearing section upon press-fitting.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a frictional force to be applied to the shaft section at a start and stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section may be formed by a fluid dynamic pressure bearing.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a friction force to be applied to the shaft section at a start or stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section may have a vertical circulatory groove provided in an inner peripheral surface thereof to enable a dynamic pressure producing liquid to be circulated around the bearing section.
A space may be formed by the shaft section, the bearing section and the sleeve to collect a dynamic pressure fluid, thereby smoothing the supply of a dynamic pressure fluid.
A radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove may be formed in a side surface of the bearing section. With this structure, the dynamic pressure producing grooves may be satisfactorily formed only in the surface of the bearing section, thus facilitating the forming and hence improving forming process efficiency.
Also, a radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove may be formed in both side surfaces of the bearing section.
The sleeve may be in a cap form, and the bearing section in the sleeve being held in the sleeve by an annular pressing member press-fitted in the sleeve.
In this case, the sleeve may have an inner peripheral surface end edge projecting greater than the pressing member to thereby form an adhesive reservoir close to the inner peripheral surface end edge of the sleeve, preventing the adhesive from flowing outside.
The base and the rotor unit at an outer peripheral edge may form an opposed portion, and a labyrinth may be formed in the opposed portion. In the event that dusts, such as magnetic particles or oil mist, accumulate at an inside portion, the above structure can prevent the magnetic particles and dusts from being discharged outside.
According to the invention, there is provided a spindle motor, further comprising: the base; a stator coil arranged in the base; a sleeve-bearing-shaft unit having the bearing section and the shaft section rotatably supported by the bearing section in the sleeve arranged in a center position of the base; and a hub unit having an inner peripheral surface mounted with the rotor magnet opposed to the stator coil and attached to the shaft section.
In case that the hub is changed in shape, it is satisfactory to change only the hub unit, requiring less increase in cost needed by the change.
The manner of connection fixing between the sleeve-bearing-shaft unit and the base may be by adhesion and press-fit or, of course, a combination of them.
Also in the invention, the constituent elements may be as follows.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a friction force to be applied to the shaft section at a start and stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve being formed of a stainless based metal material.
The bearing section may be formed by a fluid dynamic pressure bearing.
Also in this case, the shaft section has a tip formed by a convex spherical surface to thereby reduce a frictional force to be applied to the shaft section at a start and stop of the motor.
Furthermore, the bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section may have a vertical circulatory groove provided in an inner peripheral surface thereof to enable a dynamic pressure producing liquid to be circulated around the bearing section.
A space may be formed by the shaft section, the bearing section and the sleeve to collect a dynamic pressure fluid, thereby smoothing the supply of a dynamic pressure fluid.
A radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove be formed in one side surface of the bearing section. With this structure, the dynamic pressure producing grooves may be satisfactorily formed only in the surface of the bearing section, thus facilitating forming and hence improving forming efficiency.
Also, a radial dynamic pressure groove may be formed in an outer peripheral surface of the bearing section and thrust dynamic pressure producing grooves be in respective side surfaces.
The sleeve may be in a cap form, and the bearing section in the sleeve may be rotatably held in the sleeve by an annular pressing member press-fitted in the sleeve.
In this case, the sleeve has an inner peripheral surface end edge projecting greater than the pressing member to thereby form an adhesive reservoir close to the inner peripheral surface end edge of the sleeve, preventing the adhesive from flowing outside.
The base and the rotor unit at an outer peripheral edge may form an opposed portion, and a labyrinth may be formed in the opposed portion. In the event that dusts, such as magnetic particles or oil mist, accumulate at an inside portion, the above structure can prevent the magnetic particles and dusts from being discharged outside.
A wide annular groove may be circumferentially formed in an outer peripheral surface of the sleeve, and the sleeve may be press-fitted in a fitting hole opened correspondingly in the base to the sleeve thereby fixing the sleeve to the base. Fixing is possible without using an adhesive, improving operationality.
The annular groove may be also utilized as an adhesive groove, and the sleeve may be fixed to the base using both press-fit and adhesion, thereby providing further firm fixing.
The annular groove may be formed in a corresponding position to the bearing section, thereby preventing a deforming stress to be applied to the bearing section upon press-fitting.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a frictional force to be applied to the shaft section at a start and stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section may be formed by a fluid dynamic pressure bearing.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a frictional force to be applied to the shaft section at a start or stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section may have a vertical circulatory groove provided in an inner peripheral surface thereof to enable a dynamic pressure producing liquid to be circulated around the bearing section.
A space may be formed by the shaft section, the bearing section and the sleeve to collect a dynamic pressure fluid, thereby smoothing the supply of a dynamic pressure fluid.
A radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove may be formed in a side surface of the bearing section. With this structure, the dynamic pressure producing grooves may be satisfactorily formed only in the surface of the bearing section, thus facilitating forming and hence improving forming efficiency.
Also, a radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove may be formed in both side surfaces of the bearing section.
The sleeve may be in a cap form, and the bearing section in the sleeve may be held in the sleeve by an annular pressing member press-fitted in the sleeve.
In this case, the sleeve may have an inner peripheral surface end edge projecting greater than the pressing member to thereby form an adhesive reservoir close to the inner peripheral surface end edge of the sleeve, preventing the adhesive from flowing outside.
The base and the rotor unit at an outer peripheral edge may form an opposed portion, and a a labyrinth may formed in the opposed portion. This prevents magnetic particles from being discharged outside.
According to the invention, there is provided a spindle motor, further comprising: a base unit having the stator coil mounted inside the base; a stator coil arranged in the base; a sleeve-bearing-shaft unit having the bearing section and the shaft section rotatably supported by the bearing section in the sleeve arranged in a center position of the base; and a hub unit having an inner peripheral surface mounted with the rotor magnet opposed to the stator coil arid attached Lo the shaft section.
This structure uses a unit having a stator coil mounted on a base unit, and is easy to assemble and improve the operability of the spindle motor as compared to the case of mounting a stator coil single part.
The type of fixing connection between the base unit and the sleeve-bearing-shaft unit may be by any of adhesion, press-fit or a combination of them.
In the invention, the constituent elements may be as follows.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a frictional force to be applied to the shaft section at a start and stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section is formed by a fluid dynamic pressure bearing.
Also in this case, the shaft section has a tip formed by a convex spherical surface to thereby reduce a frictional force to be applied to the shaft section at a start and stop of the motor.
Furthermore, the bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section may have a vertical circulatory groove provided in an inner peripheral surface thereof to enable a dynamic pressure producing liquid to be circulated around the bearing section.
A space may be formed by the shaft section, the bearing section and the sleeve to collect a dynamic pressure fluid, thereby smoothing the supply of a dynamic pressure fluid.
A radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove may be formed in at least one side surface of the bearing section. With this structure, the dynamic pressure producing grooves may be satisfactorily formed only in the surface of the bearing section, thus facilitating forming and hence improving forming efficiency.
Also, a radial dynamic pressure groove may be formed in an outer peripheral surface of the bearing section and thrust dynamic pressure producing grooves may be formed in respective side surfaces.
The sleeve may be in a cap form, and the bearing section in the sleeve may be held in the sleeve by an annular pressing member press-fitted in the sleeve.
In this case, the sleeve has an inner peripheral surface end edge projecting greater than the pressing member to thereby form an adhesive reservoir close to the inner peripheral surface end edge of the sleeve, preventing the adhesive from flowing outside.
The base and the hub unit at an outer peripheral edge may form an opposed portion, and a labyrinth may be formed in the opposed portion. In the event that dusts, such as magnetic particles or oil mist, accumulate at an inside portion of the spindle motor, the above structure can prevent the magnetic particles and dusts from being discharged outside.
A wide annular groove may be circumferentially formed in an outer peripheral surface of the sleeve, and the sleeve may be press-fitted in a fitting hole opened correspondingly in the base to the sleeve thereby fixing the sleeve to the base. Further firm fixing may be made by utilizing the annular groove as an adhesive groove and by both press-fit and adhesion of the sleeve to the base.
The annular groove may be formed in a corresponding position to the bearing section, thereby preventing a deforming stress to be applied to the bearing section upon press-fitting.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a frictional force to be applied to the shaft section at a start and stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section may be formed by a fluid dynamic pressure bearing. In such a case, the constituent elements may be as follows.
The shaft section may have a tip formed with a convex spherical surface, thereby reducing a frictional force to be applied to the shaft section at a start or stop of the motor.
The bearing section may have a linear expansion coefficient greater than that of the sleeve, thereby having less effects upon the shaft rigidity due to temperature change.
Due to this, the bearing section may be formed of a copper based metal material, and the sleeve may be formed of a stainless based metal material.
The bearing section may have a vertical circulatory groove provided in an inner peripheral surface thereof to enable a dynamic pressure producing liquid to be circulated around the bearing section.
A space may be formed by the shaft section, the bearing section and the sleeve to collect a dynamic pressure fluid, thereby smoothing the supply of a dynamic pressure fluid.
A radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove may be formed in a side surface of the bearing section. With this structure, the dynamic pressure producing grooves may be satisfactorily formed only in the surface of the bearing section, thus facilitating forming and hence improving forming efficiency.
Also, a radial dynamic pressure producing groove may be formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove may be formed in both side surfaces of the bearing section.
The sleeve may be in a cap form, and the bearing section in the sleeve may be held in the sleeve by an annular pressing member press-fitted in the sleeve.
In this case, the sleeve may have an inner peripheral surface end edge projecting greater than the pressing member to thereby form an adhesive reservoir close to the inner peripheral surface end edge of the sleeve, preventing the adhesive from flowing outside.
The base and the hub unit at an outer peripheral edge may form an opposed portion, and a labyrinth formed in the opposed portion. In the event that dusts, such as magnetic particles or oil mist, accumulate at an inside portion, the magnetic particles and dusts can be prevented from being discharged outside.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view showing a first embodiment of a spindle motor according to the present invention;
FIG. 2 is an essential part sectional view of a modification to the spindle motor in FIG. 1 wherein a sleeve is press-fit and fixed in a base;
FIGS. 3 ( a ) thru 3 ( d ) are views showing modifications to a shaft section shown in FIG. 1;
FIG. 4 is a view showing a modification to a bearing section shown in FIG. 1;
FIG. 5 is a sectional view showing a second embodiment of a spindle motor according to the invention; and
FIG. 6 is a sectional view showing a third embodiment of a spindle motor according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Embodiments of the present invention will be described with reference to the drawings.
Referring to FIG. 1, there is illustrated a sectional view showing a first embodiment of a spindle motor according to the present invention. A spindle motor 1 comprises a base 2 , a sleeve 3 received in the base 2 , a bearing section 4 accommodated and held in the sleeve 3 , a shaft section 5 rotatably supported by the bearing section 4 , a hub 6 formed integral with the shaft section 5 , a rotor magnet 7 fixed on the hub 6 , and a stator coil 8 arranged in the vicinity of the rotor magnet 7 . The hub 6 is formed with a disc mount 19 for placing thereon a disc (not shown) as a magnetic medium.
The base 2 is formed as a case member having a fitting hole 2 A to receive the sleeve 3 . The sleeve 3 is fixed with the stator coil 8 through a proper means. The base 2 may be a member exclusive for the spindle motor 1 , or alternatively an apparatus frame on which the spindle motor 1 is to be mounted.
The sleeve 3 is a cap-like member having the annular bearing section 4 arranged at an inside thereof in a manner slightly spaced from an inner peripheral surface 3 A. The sleeve 3 is formed at its inside with an annular step 3 B press-fitted with an annular hold member 9 . Thus, the bearing section 4 is rotatably supported at a predetermined position in the sleeve 3 .
In the present embodiment, the sleeve 3 , bearing section 4 , and hold member 9 are made as a unit, i.e. structured as a sleeve-and-bearing unit U 1 . This sleeve-and-bearing unit U 1 will be handled as one unit part in a factory.
As a consequence, during assembling of the spindle motor 1 a bearing section can be provided in the base 2 by merely fixing the sleeve-and-bearing unit U 1 to the base 2 .
In the illustrated embodiment, an adhesion groove 10 is circumferentially formed in an outer peripheral surface 3 C of the sleeve 3 . In a state that an adhesive is filled in the adhesion groove 10 , the sleeve-and bearing unit U 1 is fitted and fixed in a fitting hole 2 A through adhesion. The provision of the adhesion groove 10 enables positive adhesion between the base 2 and the sleeve 3 .
Alternatively, the fixing between the base 2 and the sleeve 3 may be made by press-fit instead of adhesion.
Referring to FIG. 2, there is illustrated an essential part sectional view showing a structure where the sleeve 3 is press-fitted in the base 2 . In this case, a groove 11 is formed wide in the outer peripheral surface 3 C of the sleeve 3 . The groove 11 is provided correspondingly to the bearing section 4 in order to prevent the force acting on the outer peripheral surface of the sleeve 3 from being applied to the bearing section 4 when the sleeve 3 is press-fitted into the fitting hole 2 A of the base 2 . That is, the groove 11 has an upper end edge 11 A positioned above the bearing section 4 and a lower end 11 B below the bearing section 4 .
Incidentally, if the sleeve 3 is press-fitted in the base 2 with the groove 11 filled with an adhesive, both members are fixed by both press-fit and adhesion, providing further firm fixing.
Referring back to FIG. 1, the hold member 9 is formed with a taper 9 A at a top outer edge and further the sleeve 3 has an annular top edge 3 D projecting above the taper 9 A of the hold member 9 . This forms an annular adhesive reservoir 12 . As a result, when the hold member 9 is fixed on the sleeve 3 through an adhesive, any extra adhesive leaked through between the hold member 9 and the sleeve 3 is collected in the adhesive reservoir 12 and effectively prevented from flowing out to an outside of the sleeve 3 . Accordingly, there is less possibility that the adhesive will contaminate an interior of the spindle motor 1 which results in poor characteristics.
The bearing section 4 in the present bearing is structured as a liquid dynamic pressure bearing. That is, a radial dynamic pressure producing groove 13 is formed in an outer peripheral surface 4 A of the bearing section 4 . Thrust dynamic pressure producing grooves 14 , 15 are respectively formed in side surfaces 4 B, 4 C of the bearing section 4 . However, any one of the thrust dynamic pressure producing grooves 14 , 15 may be omitted.
The provision of the required dynamic pressure reducing grooves around the bearing section 4 in this manner needs only surface forming of the bearing section 4 . This provides an advantage that the dynamic pressure producing grooves are easy to form with efficiency.
The shaft section 5 is formed integral with the hub 6 to form a rotor. In the present embodiment the hub 6 is mounted with the rotor magnet 7 thus forming a rotor unit U 2 .
The shaft section 5 is press-fitted and fixed in an inner peripheral surface 4 D of the bearing section 4 . That is, the spindle motor 1 can be assembled by fixing the sleeve-and-bearing unit U 1 in the base 2 mounted with the stator coil 8 and then press-fitting the shaft section 5 of the rotor unit U 2 into the bearing section 4 of the sleeve-and-bearing unit U 1 thereby fixing the sleeve-and-bearing unit U 1 to the rotor unit U 2 .
Here, the shaft section 5 is formed with a convex-formed spherical surface 5 A at its tip. This provides the outer peripheral portion of the shaft section 5 at a tip thereof with a spacing from the sleeve 3 . This reduces the frictional force undergone by the shaft section 5 at a start and end of rotation, thus providing more preferred rotation characteristics.
In this case, a space 16 is formed between the shaft section 5 , the sleeve 3 , and the bearing section 4 , to allow dynamic pressure producing liquid to be collected therein. It is therefore possible to supplement for evaporation of dynamic pressure producing liquid over a long period of time.
Incidentally, the means to form the space 16 is not limited to the above but may be in forms as exemplified in FIG. 3A to FIG. 3 D. FIG. 3A shows a case of providing a concave spherical surface 5 a in the shaft section 5 , FIG. 3B a case of forming a depression 5 b inward the shaft section 5 , FIG. 3C a case of forming a convex portion 5 c in a center of the shaft section 5 , and FIG. 3D a case that a space 16 is formed between a tip of the shaft section 5 and the sleeve 3 when the shaft section 5 is shortened in length and the shaft section 5 is press-fitted into the bearing section 4 .
It is noted that a space 16 if provided in this manner may cause occurrence of air bubbles due to negative pressure of the liquid collected there upon rotation of the shaft section 5 . In order to solve such a disadvantage, vertical circulatory grooves 17 may be formed in the inner peripheral surface of the bearing section 4 .
Referring to FIG. 4, there is illustrated a bearing section 4 provided with vertical circulatory grooves 17 . The provision of at least one or, if necessary, a plurality of such vertical circulatory grooves 17 can cause a required liquid to circulate around the bearing section 4 thereby supplying a proper amount of a required liquid for producing dynamic pressure to the bearing section 4 .
In the meanwhile, in the structure as shown in FIG. 1 temperature change may cause deformation in each part as well as change in viscosity of the dynamic pressure producing liquid, which changes the rigidity of the shaft in the bearing section 4 causing a worse effect on torque characteristics of the spindle motor 1 . In order to avoid this, the embodiment of FIG. 1 has a linear expansion coefficient of the bearing section 4 set greater than a linear expansion coefficient of the sleeve 3 . This provides a structure that, if temperature changes, both the members compensate for each other to have a shaft rigidity less affected by temperature.
Specifically, this is achieved by making the sleeve 3 of a copper based metal material and the bearing section 4 of a stainless steel based metal material.
As shown in FIG. 1, in the spindle motor 1 the hub 6 at its outer end is close to the sleeve 3 , forming a labyrinth 18 . As a result, in the case where dusts such as magnetic particles or oil mist accumulate within the spindle motor 1 , such magnetic particles or dusts produced are effectively prevented from scattering to an outside. Accordingly, where the spindle motor 1 is mounted for example in a hard disc drive apparatus, dusts such as magnetic particles or oil dust are prevented from scattering thus helping realize a high performance hard disc drive apparatus.
Referring to FIG. 5, there is illustrated a second embodiment of a spindle motor 101 according to the invention. This spindle motor 101 basically employs the same parts as those constituting for the spindle motor 1 . Accordingly, the corresponding parts of the spindle motor 101 to those of the spindle motor 1 are denoted by the same reference numerals of a 100 level, omitting explanations thereof.
The spindle motor 101 is different from the spindle motor 1 only in that a shaft 105 and a hub 106 are separated, a sleeve 103 , bearing section 104 , shaft section 105 and hold member 109 are made as a unit to form a sleeve-bearing-shaft unit U 3 , and the hub 106 and rotor magnet 107 are made as a unit forming a hub unit U 4 .
According to the structure of the spindle motor 101 , if only the hub 106 must be modified in specification, it will be satisfactory to change only the hub unit U 4 , offering for advantage in cost.
As for each part of the spindle motor 101 , various modifications are possible similarly to the above explanation, hence providing a similar advantage.
Referring to FIG. 6, there is illustrated a third embodiment of a spindle motor 201 according to the invention. This spindle motor 201 basically employs the same parts as those for the spindle motor 1 of FIG. 1 . Accordingly, the corresponding parts of the spindle motor 201 to those of the spindle motor 1 are denoted by the same reference numerals of a 200 level, omitting explanations thereof.
The spindle motor 201 is different from the spindle motor 1 only in that a shaft 205 and a hub 206 are separated, a sleeve 203 , bearing section 204 , shaft section 205 , and hold member 209 are made as a unit to form a sleeve-bearing-shaft unit U 5 , the hub 206 and rotor magnet 207 are made as a unit forming a hub unit U 6 , and a stator coil 208 is fixed on the sleeve 203 into a unit constituting as a base unit U 7 .
According to the structure of the spindle motor 201 , if the hub 206 must be modified in accordance with specification, it will be satisfactory to change only the hub unit U 6 , thus offering convenience.
As for each part of the spindle motor 201 , various modifications are possible similarly to the case of the spindle motor 1 of FIG. 1 hence providing a similar advantage.
According to the present invention, because the constituent elements are utilized for spindle motor are, it is possible to implement checking on a unit-by-unit basis during manufacture. If there is an unacceptable unit, it is satisfactory to merely scrap the same unit. In the case that some parts require modification due to diversification of specifications, the unitized common parts can be still used without change, making it unnecessary to increase parts for each model. Also, such unitization makes possible to cope with an unacceptable unit by merely removing it. Thus, cost reduction is to be expected. In this manner, parts can be made common for all the models, resulting in cost reduction. Furthermore, even where a part is built in an apparatus and thereafter becomes poor, the apparatus and its parts can be reusable.
The other effects of the invention will be listed below.
An adhesive groove is provided in an outer peripheral surface of the sleeve to hold an adhesive for fixing the sleeve to the base, and the sleeve at the outer peripheral surface is fixed to the base through the adhesive. Fixing with adhesion is favorably made.
Because the shaft section has a tip formed with a convex spherical surface, it is possible to reduce a frictional force to be applied to the shaft section at a start and stop of the motor. Thus, a high performance motor is realized.
Because the bearing section has a linear expansion coefficient greater than that of the sleeve, the shaft rigidity is less affected due to temperature change.
In the case of making the bearing section as a fluid dynamic pressure bearing, a vertical circulatory groove is provided in an inner peripheral surface of the bearing section. Accordingly, a dynamic pressure producing fluid can be circulated around the bearing, thereby obtaining a favorable bearing characteristics.
Because a space is formed by the shaft section, the bearing section, and the sleeve to collect a dynamic pressure fluid, a dynamic pressure fluid is smoothly supplied.
A radial dynamic pressure producing groove is formed in an outer peripheral surface of the bearing section and a thrust dynamic pressure producing groove is formed in one side surface of the bearing section. Accordingly, it is satisfactory to form the dynamic pressure producing grooves only in the surface of the bearing section. This facilitates forming and hence improving forming efficiency.
Because the sleeve is made in a cap form and the bearing section in the sleeve is rotatably held in the sleeve by an annular pressing member press-fitted in the sleeve, assembling is easy to perform.
In this case, if the sleeve has an inner peripheral surface end edge projecting greater than the pressing member to thereby form an adhesive reservoir close to the inner peripheral surface end edge of the sleeve, it is possible to prevent the adhesive from flowing outside.
If the base and the rotor unit at an outer peripheral edge form an opposed portion and a labyrinth is formed in the opposed portion, then in the event that dusts, such as magnetic particles or oil mist, accumulate at an inside portion, it is possible to prevent them from being discharged to an outside. This is very effective if applied for a hard disc drive apparatus.
If a wide annular groove is circumferentially formed in an outer peripheral surface of the sleeve and the sleeve is press-fitted in a fitting hole opened correspondingly in the base to the sleeve thereby fixing the sleeve to the base, then fixing is possible without using an adhesive, thus improving operationality.
The annular groove may be also utilized as an adhesive groove, and the sleeve may be fixed to the base using both press-fit and adhesion, thereby providing further firm fixing.
If the annular groove is formed in a corresponding position to the bearing section, no deforming stress is applied to the bearing section upon press-fitting. Thus, high performance bearing can be realized. | A spindle motor comprises a base, a stator coil connected to the base, and a sleeve-and-bearing unit connected to a central portion of the base. The sleeve-and-bearing unit has a sleeve and a bearing section mounted in the sleeve having a linear expansion coefficient greater than that of the sleeve. The sleeve has a groove disposed in an outer peripheral surface thereof for receiving an adhesive material for connecting the base to the outer peripheral surface of the sleeve. A rotor unit is connected to the sleeve-and-bearing unit for undergoing rotation relative to the sleeve-and-bearing unit. The rotor unit has a shaft section supported by the bearing section for undergoing rotation, a hub connected to the shaft section for rotation therewith, and a rotor magnet connected to the hub and disposed opposite to and spaced apart from the stator coil. | 5 |
BACKGROUND OF THE INVENTION
The present invention provides novel compositions of matter and processes for their preparation. Particularly, the present invention relates to novel chemical intermediates and associated processes for the preparation of furochromones. Most especially, the present invention provides for the preparation of novel antiatherosclerotic furochromones, particularly khellin analogs.
Khellin and related compounds are known to exert a wide variety of pharmacological effects. Recently, khellin has been reported to exhibit useful antiatherosclerotic activities. Moreover, numerous analogs of khellin likewise are known to exert useful antiatherosclerotic effects. For example, 7-methylthiomethyl-4,9-dimethoxyfurochromone is described in U.S. Pat. No. 4,284,569 as such a useful antiatherosclerotic substance.
Methods for the total synthesis of khellin are known. For example, pyrogallol has been employed as a starting material for the synthesis of furochromones such as khellin. See Clarke, J. R., et al., J. Chem. Soc., 302 (1949), Baxter, R. A., et al., J. Chem. Soc., S30 (1949), Schonberg, A., et al., J. Am. Chem. Soc., 73: 2960 (1951), Murti, V. V. S., et al., Proc. of the Indian Acad. of Sci., 30A: 107 (1949), and Geissman, T. A., et al., J. Am. Chem. Soc., 73: 1280 (1951). Also descriptive of the synthesis of khellin are Spath, E., et al., Chem. Ber., 71: 106 (1938), Dann, O., et al., Chem. Ber., 83: 2829 (1960), Dann, O., et al., Ann. Chem., 605: 146 (1957), and Murti, V. V. S., et al., J. Sci. Ind. Res. (India), 8B: 112 (1949). See also U.S. Pat. No. 2,680,119 describing the synthesis of khellin and related compounds.
Other references describing the synthesis of intermediates useful in the preparation of khellin for analogs include: Aneja, R., et al., Chem. Ber., 93: 297 (1960), Aneja, R., et al., J. Sci. Ind. Res. (India), 17B: 382 (1958), Gardner, T. S., et al., J. Org. Chem., 15: 841 (1950), and Rowe, L. R., et al., Indian J. Chem., 5: 105 (1967).
Accordingly, the references cited above describe the preparation of 1-(6-hydroxy-4,7-dimethoxy-5-benzofuranyl)-ethanone. Also known is the related compound 6-hydroxy-4,7-dimethoxy-5-benzofurancarboxylic acid, methyl ester, described by Musante, C., Gazz. Chim. Ital., 88: 910 (1958).
PRIOR ART
Methods of the total synthesis of khellin are known, as are certain chemical intermediates useful in its synthesis.
The use of pyrogallol in the synthesis of khellin intermediates is known. For example, the transformation of pyrogallol to the khellin intermediate 1-(2,3-dihydro-6,7-dihydroxy-5-benzofuranyl)ethanone is known. The parahydroxylation of this intermediate is also known. See Row, L. R., et al., Indian J. Chem., 5: 105 (1967) describing this transformation and the subsequent dimethylation to yield known khellin intermediates. U.S. Pat. No. 4,284,569 provides a variety of novel anti-atherosclerotic furochromones.
SUMMARY OF THE INVENTION
The present invention particularly provides:
(a) A method of preparing a dialkoxybenzofuran of formula I, wherein R 2 and R 3 are C 1 -C 4 alkyl, being the same or different, which comprises para-alkoxylating a mono-alkoxybenzofuran of formula II, wherein R 2 is as defined above, with an oxidizing reagent selected from the group consisting of
(i) thallium (III) nitrate,
(ii) ceric ammonium nitrate,
(iii) lead tetraacetate,
in a C 1 -C 4 alkanol solvent of the formula R 3 OH,
wherein R 3 is as defined above;
(b) A benzofuran of formula III,
wherein R 2 is C 1 -C 4 alkyl;
(c) A benzofuran of formula IV,
wherein R 5 is C 2 -C 4 alkyl;
(d) A benzofuran of formula V,
wherein one of R 6 and R 7 is C 1 -C 4 alkyl and the other is C 2 -C 4 alkyl with the proviso that R 6 and R 7 are different;
(e) An anti-atherosclerotic furochromone of formula VI,
wherein R 6 and R 7 are as defined above;
wherein R 12 is:
(1) hydrogen;
(2) C 1 -C 8 alkyl;
(3) C 2 -C 8 alkoxymethyl;
(4) C 2 -C 8 alkylthioalkyl;
(5) trifluoromethyl;
(6) phenoxymethyl optionally substituted by chloro, fluoro, trifluoromethyl, C 1 -C 3 alkyl or C 1 -C 3 alkoxy;
(7) phenylthiomethyl optionally substituted by chloro, fluoro, trifluoromethyl, C 1 -C 3 alkyl or C 1 -C 3 alkoxy;
(8) --CH 21 --S(O) n --R 20 , wherein n is zero, one or 2 and R 20 is C 1 -C 5 alkyl; or
(9) --CH 2 NR 8 R 9 , wherein R 8 and R 9 are hydrogen, C 1 -C 12 alkyl or wherein R 8 and R 9 , taken together with N, form a saturated or unsaturated heterocyclic amine ring consisting of from 2 to 7 carbon atoms, inclusive, and zero, one, or 2 additional hetero atoms, with the proviso that said heterocyclic amine ring contains 4 to 8 atoms in the ring, said additional hetero atoms being selected from the group consisting of oxygen, nitrogen, and sulfur, said heterocyclic amine ring being optionally substituted by C 1 -C 4 alkyl, C 2 -C 8 alkylthiomethyl or alkoxymethyl C 1 -C 4 hydroxyalkyl, or phenyl;
wherein R 13 is:
(1) hydrogen;
(2) chloro, iodo, or bromo; or
(3) --CH 2 --S(O) n --R 20 wherein n and R 20 are as defined above, with the proviso that R 13 is --CH 2 --S(O) n --R 20 only when R 14 is methyl;
(f) 4-Ethoxy-9-methoxy-7-methylthiomethylfurochromone; and
(g) 4-Methoxy-9-ethoxy-7-methylthiomethylfurochromone.
In accordance with the method described above, there is prepared the formula II alkoxybenzofuran. This formula II alkoxybenzofuran wherein R 2 is methyl is known to be useful in the preparation of a wide variety of anti-atherosclerotic substances, including khellin and various analogs thereof. See U.S. Pat. No. 4,284,569.
Similarly there are prepared the novel formula XI benzofurans when R 1 is C 2 -C 4 alkoxy. These intermediates are useful in the preparation of novel anti-atherosclerotic 4,9-di-(C 2 -C 4 )-alkoxyfurochromones of formula VIII by means described in U.S. Pat. No. 4,284,569 for the preparation of the corresponding 4,9-dimethoxyfurochromones therein. Moreover, the manner of use of the novel 4,9-di-(C 2 -C 4 )-alkoxy-furochromones of formula VIII in the treatment and prevention of atherosclerosis is the same as that described in U.S. Pat. No. 4,284,569 for the corresponding 4,9-dimethoxy compounds. Accordingly, the manner of the preparation and pharmacological use of these novel formula VIII compounds is incorporated herein by and reference from the description of the preparation and use in U.S. Pat. No. 4,284,569 of the antiatherosclerotic 4,9-dimethoxyfurochromones. Among the novel formula VIII compounds herein, the 4,9-diethoxyfurochromones are preferred.
The process of the present invention is more completely understood by reference to the charts below. In these charts, R 1 is hydrogen or C 1 -C 4 alkyloxy or hydrogen. R 2 , R 3 , R 12 and R 13 are as defined above.
R 11 is:
(a) hydrogen;
(b) C 1 -C 8 alkyl;
(c) C 2 -C 8 alkoxymethyl;
(d) C 2 -C 8 alkylthioalkyl;
(e) trifluromethyl;
(f) phenoxymethyl;
(g) phenylthiomethyl;
(h) phenoxymethyl or phenylthiomethyl, either of which is optionally substituted by one chloro, fluoro, trifluoromethyl, C 1 -C 3 -alkyl, or C 1 -C 3 -alkoxy; or
(i) C 3 -C 10 cycloalkyl.
The carbon atom content of various hydrocarbon containing moities is indicated by a prefix designating the minimum and maximum number of carbon atoms in the moiety, i.e., the prefix C i -C j indicates a carbon atom content of the integer "i" to the integer "j" carbon atoms, inclusive. Thus, C 1 -C 3 alkyl refers to alkyl of 1-3 carton atoms, inclusive, or methyl, ethyl, propyl, and isopropyl.
With respect to the charts, Chart A provides a method whereby the known formula XXI compound is transformed to the novel formula XXV 2,3-dihydro-benzofuran, which is in turn reduced to the known formula XXVI benzofuran intermediate for preparing desmethoxy khellin and other khellin analogs.
With further respect to Chart A, pyrogallol is converted to the formula XXII triacetate first by treatment with chloroacetonitrile according to procedures described by Geissman, T. A., et al., J. Amer. Chem. Soc., 73: 57-65 (1951).
Thereafter the formula XXIII production product is obtained from the formula XXII compound employing a metal catalyst under a hydrogen atmosphere. For example, conventional metal catalysts such as palladium and carbon catalysts are employed. See Dann, O. and Zeller, H. G., Ber. 93: 28-29 (1960) for a transcription of this transformation.
Thereafter the formula XXIII compound then to go to Fries rearrangement to yield formula XXIV dihydroxy ketone. By this procedure, the formula XXIII compound is treated with a mixture of aluminium trichloride and nitrobenzene.
This formula XXIV compound is then selectively C 1 -C 4 alkylated to the formula XXV compound by treatment with an alkyl iodide. Any concomitant desalkoxylation in this reaction is reversed by treatment with hydrobromic acid.
This novel formula XXV compound is then dehydrogenated using 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ). See Linn, Y. Y., et al., J. Heterocyclic Chem., 799 (1979).
The formula XXVI compound thusly prepared is a highly useful intermediate in the synthesis of analogs of khellin, specifically the 4-desmethoxy khellin. See, for example, U.S. Pat. No. 4,284,569, describing the synthesis of such analogs from the formula XXVI compound wherein R 2 is methyl.
With respect to Chart B, a method is provided for the paraalkoxylation of the formula XXXI compound, prepared as the formula XXVI compound in Chart A. This methoxylation preceeds by the use of an oxidizing agent in a C 1 -C 4 alkanol solvent corresponding to the alkoxy group to be introduced at C 4 . Pb(OAc) 4 may be employed as the oxidizing agent. See Brother, A. E., et al., Helv. Chim. Acta., 35: 9-10 (1952). Alternatively, however, thallium (III) nitrate is employed as the oxidizing agent. See Taylor, E. C., J. Organic Chem., 41: 282 (1976). In the latter case, maximum yields are obtained when the oxidizing agent is added over a period of about 15 min with the reaction mixture being maintained at about -25° C. for 30 min followed by heating for 1-2 min.
Chart C provides an illustration of the method by which the formula XLI compound, prepared as the formula XXVI compound of Chart A or the formula XXXII compound of Chart B, is transformed to khellin 4-desmethoxy khellin or analogs thereof. Procedures of Chart C are, for example, known in the art from U.S. Pat. No. 4,284,569 wherein Chart A of that patent describes the synthesis of the various formula XLII and formula XLIII compounds from the formula XLI starting material. Accordingly, the charts herein provide a description of the preparation and use of the novel process and compounds of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The present disclosure is more fully understood by the operation of the following examples:
EXAMPLE 1
3,6,7-Benzofurantriol triacetate (Formula XXII)
Refer to Chart A
Dry zinc chloride (38 g) is added to pyrogallol (Formula XXII, 35 g). To these solids under a nitrogen atmosphere is added diethyl ether and chloroacetonitrile (18 ml). The resulting mixure is then stirred and cooled to 0° C. Hydrochloride gas is then bubbled to the reaction mixture for 30 min, the mixture is allowed to warm slowly to ambient temperature with stirring for 12 hr. Thereafter, the two-face mixture is cooled to 0° C. and the ether layer decanted. Additional diethyl ether (100 mg) is added, stirred, and decanted. Water (250 ml) is added to the resulting residue and the aqueous mixture is then refluxed for 30 min yielding a homogeneous solution. The solution is then cooled to 4° C., filtered, and yields a reddish-brown solid (24.5 g), α-chlorogallacetophenone. Without further purification, the solid is then dissolved in ethanol (300 ml) containing sodium acetate (24.5 g). After refluxing for 5 hr, the resulting mixture is then dried and treated with acetic anhydride (150 ml) and pyridine (75 ml). The resulting mixture is then stirred at ambient temperature for 12 hr, decanted into ice water (700 ml) and stirred for one hr. The resulting precipitate is then collected on a filter, washed with water and air dried. Thereafter, the filtrate is acidified with coconcentrated hydrochloric acid and extracted with ethyl acetate. The organic extracts are then washed thoroughly with saturated sodium bicarbonated brine, dried over magnesium sulphate, and concentrated to a residue. Chromatography on 1.3 kg of silica gel alluding with 40% ethyl acetate Skellysolve B ethyl acetate to obtain 27.75 g of pure product, a white solid, melting point 99°-101° C.
EXAMPLE 2
2,3-Dihydro-6,7-benzofurandiol diacetate (Formula XXIII)
A mixture of the title product of Example 1 (50 g) in ethyl acetate (350 ml) is treated with anhydrus potassium acetate (7.5 g) and 7.5 g of a 10% paladium on carbon catalyst. The reaction mixture is then hydrogenated at 65° C. for 2 hr, cooled to ambient temperature, and filtered through diaconaceous earth. The resulting filtrate is then concentrated under reduced pressure yielding a solid. Recrystallization from 250 ml of ethyl acetate and Skellysolve B (1:1) yields 33.65 g of pure title product as a white solid, melting point 114°-115° C. Silica gel TLC R f is 0.31 in 25% ethyl acetate in hexane. IR absorptions (cm -1 ) are observed at 1765, 1625, 1610, 1490, 1465, 1375, 1225, 1210, 1180, and 1035. NMR -absorptions are observed at 7.05, 6.62, 4.64, 3.21, 2.25, and 2.23 δ.
EXAMPLE 3
1-(2,3-dihydro-6,7-dihydroxy-5-benzofuranyl)-ethanone (Formula XXIV)
Refer to Chart A
A mixture of the title product of Example 2 (9.50 g), nitrobenzene (100 ml) and aluminium trichloride (6.36 g) is heated at 60° C. for 90 min. After cooling to ambient temperature, the reaction mixture is poured over ice and 2N hydrochloric acid (100 ml) is added, followed by the addition of water (300 ml). After stirring for 3 hr, the reaction mixture is then extracted with ethyl acetate. The organic layer is then separated and washed with 5% aqueous sodium hydroxide and the aqueous layer then poured into 2N hydrochloric acid (500 ml), yielding a precipitate. Ethyl acetate is then added and then separated from the aqueous layer. The organic layer is then dried over magnesium sulphate and concentrated under reduced pressure to yield 6.35 g of title product as a brown solid. Recrystallization from ethyl acetate yields pure crystalline product, melting point 190°-190.5° C. Silica gel TLC R f is 0.25 in 5% ethyl acetate in trichloromethane. IR absorptions (cm -1 ) are observed at 3460, 3200, 1645, 1605, 1490, 1445, 1365, 1320, 1255, and 1055. NMR absorptions are observed at 7.15, 4.70, 3.18, and 2.52 δ.
EXAMPLE 4
1-(2,3-dihydro-6-hydroxy-7-methoxy-5-benzofuranyl)-ethanone (Formula XXV: R 2 is methyl)
Refer to Chart A
A mixture of the title product of Example 3 (5.9 g) potassium carbonate (12 g) and methyl iodide (25 g) is heated at reflux and acetone for 18 hr. After cooling to ambient temperature and removal of the potassium carbonate by filtration, the resulting mixture is then concentrated under reduced pressure to a yellow oil. The oil is then dissolved in trichloromethane and treated with hydrobromic acid and refluxed for 2 hr. After cooling to ambient temperature and concentration under reduced pressure, chromatography eluting with 5% ethyl acetate in trichloromethane yields 6.0 g of pure title product, melting point 95°-97° C. Silica gel TLC R f is 0.5 in 5% ethyl acetate in trichloromethane. IR absorptions (CM -1 ) are observed at 2700, 1630, 1615, 1430, 1405, 1365, 1330, 1290, and 1060. NMR absorptions are observed at 7.3, 6.48, 3.9, and 3.15 δ.
EXAMPLE 5
1-(6-hydroxy-7-methoxy-5-benzofuranyl)-ethanone (Formula XXVI: R 2 is methyl)
Refer to Chart A
To a solution of the title product of Example 4 (12.1 g) in dioxane is added 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ, 17.8 g). The resulting black solution is then stirred at reflux for 2 hr. Upon cooling to ambient temperature, a precipitate forms. The reaction mixture is then filtered and the filter cake is washed with dichloromethane. The filtrate is then concentrated to a residue and the residue chromatographed on 700 g of silica gel eluting with dichloromethane. Pure title product is obtained as 5.5 g of an oil which spontaneously crystallizes. Recrystallization from ethyl acetate in hexane (1:5) yields pure title product, melting point 61.2°-63.5° C. Silica gel TLC R f is 0.31 in 25% ethyl acetate in hexane. IR absorptions (CM -1 ) are observed at 3140, 3110, 2720, 1635, 1625, 1545, 1320, 1300, 1275, and 1050. NMR absorptions are observed at 7.78, 7.65, 4.21, and 2.71 δ.
EXAMPLE 6
1-(6-hydroxy-4,7-dimethoxy-5-benzofuranyl)-ethanone (Formula XXXII: R 2 and R 3 are both methyl)
Refer to Chart B
A. The title product of Example 5 (100 mg) is added to methanol (4 ml) and cooled to -25° C. To the resulting heterogeneous mixture is added a methanolic (7 ml) solution of thallium (III) nitrate trihydrate, TL (ONO 2 ) 3 .3H 2 O (250 mg), dropwise over about 15 min. The resulting mixture is then stirred for 30 min at -25° C. and heated to reflux for 1-2 min. The reaction is then poured into saturated aqueous sodium bicarbonate and extracted with diethyl ether. The etheral layer is then dried over magnesium sulphate and concentrated under reduced pressure to yield a yellow oil. Crystallization is achieved by dissolving the oil in 1% ethyl acetate in hexane and cooling to 0° C. for 12 hr. Filtration of the resulting crystals yields 70 mg of pure title product, melting point 98°-99° C. Silica gel TLC R f is 0.6 in ethyl acetate at hexane (1:1). IR absorptions (CM -1 ) are observed at 2955, 2930, 2926, 2868, 1629, 1619, 1587, 1471, 1452, 1444, 1425, 1382, 1364, 1303, 1267, 1151, 1079, 1061, and 755. NMR absorptions are observed at 7.5, 6.9, 4.15, 4.05, and 2.7δ.
B. Alternatively title product is prepared utilizing lead tetraacetate (200 mg) which is added to methanol (6 ml) and cooled to 0° C. To the resulting solution is added the title product of Example 5 (100 mg) dropwise in methanol (5 ml). The resulting mixture is then stirred at 0° C. for 80 min and poured into saturated aqueous sodium bicarbonate. After extraction with ether, the etheral solution is then dried over magnesium sulphate and concentrated under reduced pressure to yield a yellow oil. This crude solid is then dissolved in methanol and heated at reflux for 1 hr. After cooling to ambient temperature and removal of solvent under reduced pressure, crystallization from 1% ethyl acetate in hexane yields 70 mg of pure title product, melting point 98°-100° C.
EXAMPLE 7
7-Methylthiomethiomethyl-7-methoxy-9-ethoxy-furochromone (Formula XXIII: R 1 is methyl, R 2 is ethyl, R 12 is methylthiomethyl, and R 13 is hydrogen)
Refer to Charts A, B, and C
A. A mixture of the title product of Example 3 (5.9 g) potassium carbonate (12 g) and ethyl iodide (28 g) is heated at reflux and acetone for 18 hr. After cooling to ambient temperature and removal of the potassium carbonate by filtration, the resulting mixture is then concentrated under reduced pressure. The residue is then dissolved in trichloromethane and treated with hydrobromic acid and refluxed for 2 hr. After cooling to ambient temperature and concentration under reduced pressure, chromatography eluting with 5% ethyl acetate in trichloromethane yields 6.0 g of formula XXV product.
B. To a solution of the product of Part A (12 g) in dioxane is added 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ, 17.8 g). The resulting black solution is then stirred at reflux for 2 hr. Upon cooling to ambient temperature, a precipitate forms. The reaction mixture is then filtered and the filter cake is washed with dichloromethane. The filtrate is then concentrated to a residue and the residue chromatographed on 700 g of silica gel eluting with dichloromethane to obtain formula XXVI product, 1-(6-hydroxy-7-ethoxy-5-benzofuranyl)-ethanone.
C. The formula XXVI product of Part B (100 mg) is added to methanol (4 ml) and cooled to -25° C. To the resulting mixture is added a methanolic (7 ml) solution of thallium (III) nitrate trihydrate, TL (ONO 2 ) 3 .38 2 O (250 mg), dropwise over about 15 min. The resulting mixture is then stirred for 30 min at -25° C. and heated to reflux for 1-2 min. The reaction is then poured into saturated aqueous sodium bicarbonate and extracted with diethyl ether. The etheral layer is then dried over magnesium sulphate and concentrated under reduced pressure to yield formula XXXII product, 1-(6-hydroxy-4-methoxy-7-ethoxy-5-benzofuranyl)-ethanone.
D. To sodium hydride (20.1 g of a 50% dispersion in oil) and tetrahyrofuran (20 ml freshly distilled from lithium aluminum hydride), combined under a nitrogen atmosphere to form a slurry, are added dropwise a mixture of the product of Part C (56 g), ethyl 2-(methylthio)-acetate (26.4 g) and dry tetrahydrofuran (50 ml). After the addition is complete (1.5 hr) the reaction mixture is then heated on a steam bath for 15 min and cooled to ambient temperature. Thereupon excess sodium hydride is destroyed by careful addition of ice and water (300 ml). Washing with diethyl ether (600 ml) yields an aqueous layer which is diluted with methanol (100 ml) and concentrated hydrochloric acid (75 ml). This mixture is then refluxed for 45 min and thereupon allowed to cool to ambient temperature. Upon extraction with methylene chloride (600 ml) the organic extracts are dried and concentrated under reduced pressure to yield pure title product.
EXAMPLE 8
7-Methylthiomethiomethyl-4-ethoxy-9-methoxyfurochromone (Formula XXIII: R.sub. 1 is ethyl, R 2 is methyl, R 12 is methylthiomethyl, and R 13 is hydrogen)
Refer to Chart A, B, and C
A. The title product of Example 5 (100 mg) is added to ethanol (4.5 ml) and cooled to -25° C. To the resulting mixture is added an ethanolic (8 ml) solution of thallium (III) nitrate trihydrate, TL (ONO 2 ) 3 .38 2 O (250 mg), dropwise over about 15 min. The resulting mixture is then stirred for 30 min at -25° C. and heated to reflux for 1-2 min. The reaction is then poured into saturated aqueous sodium bicarbonate and extracted with diethyl ether. The etheral layer is then dried over magnesium sulphate and concentrated under reduced pressure to yield formula XXXII product, 1-(6-hydroxy-4-ethoxy-7-methoxy-5-benzofuranyl)-ethanone.
B. To sodium hydride (20.1 g of a 50% dispersion in oil) and tetrahydrofuran (20 ml freshly distilled from lithium aluminum hydride), combined under a nitrogen atmosphere to form a slurry, are added dropwise a mixture of the product of Part A (56 g), ethyl 2-(methylthio)-acetate (26.4 g) and dry tetrahydrofuran (50 ml). After the addition is complete (1.5 hr) the reaction mixture is then heated on a steam bath for 15 min and cooled to ambient temperature. Thereupon excess sodium hydride is destroyed by careful addition of ice and water (300 ml). Washing with diethyl ether (600 ml) yields an aqueous layer which is diluted with methanol (100 ml) and concentrated hydrochloric acid (75 ml). This mixture is then refluxed for 45 min and thereupon allowed to cool to ambient temperature. Upon extraction with methylene chloride (600 ml) the organic extracts are dried and concentrated under reduced pressure to yield pure title product.
C. Alternatively title product is prepared as follows:
(1) 4,7-Dimethoxy-7-[(methylthio)methyl]-furochromone (15 g) is added to trichloromethane (250 ml). Anhydrous hydrobromic acid is then bubbled through the resulting mixture until a dark red color develops. The reaction is then heated to reflux for 45 min, cooled to ambient temperature, and diluted with water (200 ml). The organic layer is then separated, dried over magnesium sulphate, and concentrated under reduced pressure to yield 13.36 g of 4-hydroxy-7-[(methylthio)methyl]-9-methoxy-furochromone. Melting point 134°-135° C.
(2) The product of part C(1) (4.0 g) is added to acetone (100 ml), ethyl iodide (15 ml) and potassium carbonate (9 g). The resulting mixture is then heated to reflux for 18 hr, cooled to ambient temperature, and concentrated under reduced pressure. The resulting solid is then washed with trichloromethane and separated by filtration. Concentration under reduced pressure yields a dark oil which is chromatographed on 300 gr of silica gel by high pressure liquid chromatography. Packing in elution with 10% ethyl acetate in trichloromethane yields 3.0 g of title product, melting point 112°-114° C. Silica gel TLC Rf is 0.78 in 1% methanol in ethyl acetate. IR absorptions (cm -1 ) are observed at 3120, 1650, 1610, 1380, 1340, 1210, 1170, and 1065. NMR absorptions are observed at 7.62, 6.97, 6.15, 4.21, 4.20, 4.57, and 2.21δ. ##STR1## | The present invention provides a total synthesis of known intermediates useful in the synthesis of khellin and antiatherosclerotic analogs thereof from pyrogallol. Pyrogallol is converted to 3,6,7-benzofurantriol triacetate using zinc chloride and chloracetanitrile, then catalytically reduced and deactoxylated at the 3 position to yield the corresponding 2,3-dihydrofuran. This substance is subjected to a Fries rearrangement to the corresponding diol, the phenolic hydroxyl group of which is then selectively alkylated. This yields 6-hydroxy-7-alkoxy-5-benzofuranyl methyl ketone, a known intermediate for the production of 4-desmethoxy khellin and analogs thereof. This compound is then selectively alkoxylated at the 4 position using lead tetraacetate or thallium (III) nitrate in an alkanol solvent to yield known chemical intermediates in the preparation of khellin and analogs thereof. | 2 |
TECHNICAL FIELD
[0001] The disclosure refers to an automatic dispenser for periodically spraying an amount of liquid from at least two aerosol containers.
[0002] In one embodiment, the two aerosol containers contain liquids of different nature, such as different perfume or active substance composition, so that the same device is capable of dispensing alternatively two or more different substances.
BACKGROUND
[0003] Automatic spray dispensing devices for periodically spraying liquids, are very well, known in the state of the art. Typically these devices comprise one aerosol nozzle for spraying a first liquid, which is activated by a cam or level element in turn operated by a DC electric motor.
[0004] An electronic timer is associated to said electric motor to activate the spray valve at predeterminated periods of time.
[0005] Some examples of prior art aerosol dispensers are described in the followings patents: U.S. Pat. No. 4,483,466, U.S. Pat. No. 3,739,944 and U.S. Pat. No. 5,249,718.
[0006] It has been detected the need for more sophisticated devices, which offer to the consumers more options to perfume or treat an environment, but at the same time can be manufactured at a very low cost.
BRIEF SUMMARY
[0007] The disclosure refers to an automatic spray dispensing device comprising a first spray valve for spraying a liquid, and a cam element pivotally mounted in the device and arranged to move from a rest position in which the valve is not activated to a first activation position in which it activates said first spray valve by pushing it down.
[0008] The operation of a spray valve is very well known for the skilled person in the art, thus it is not necessary to explain it in detail for the comprehension of the invention.
[0009] The cam element is operated by an electric engine, and an electronic timer is associated with said electric engine to command its operation.
[0010] The device is characterised in that it is provided with a second spray valve, and the cam element is configured to selectively activate said first and second spray valves by means of the action of said engine.
[0011] For that purpose, the engine is operated by electronic means to change the direction of rotation of the same, in such a manner that when the shaft of the engine turns in one direction, the cam element activates one of the spray valves, and when the shaft turns in the other direction the other spray valve is activated by the cam element.
[0012] The spray dispensing device of the invention is therefore capable of alternatively spraying two different liquids at selected periods of time, for that only one electric motor is advantageously used in order to maintain a low manufacturing cost.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] To complement the description being made and to aid towards a better understanding of the characteristics of the invention, in accordance with a preferred example of embodiment thereof, a set of drawings is attached as an integral part of said description, wherein the following has been represented, with an illustrative, non-limiting character:
[0014] FIG. 1 .—shows a rear perspective view of the device with the cam element in a rest position, and part of the housing removed.
[0015] FIG. 2 .—shows another perspective view similar to FIG. 1 , wherein all parts of the housing have been removed for the shake of clarity of the figure.
[0016] FIG. 3 .—shows a front perspective view of the device wherein all parts of the housing have been removed.
[0017] FIG. 4 .—shows another perspective view similar to FIG. 3 , showing the internal components of the device.
[0018] FIG. 5 .—shows a perspective view of the device with the housing closed.
DETAILED DESCRIPTION
[0019] FIG. 1 shows a preferred embodiment of the invention, in which the spray dispensing device comprises a housing ( 1 ) inside which are mounted two spray valves (not shown) associated respectively to a first and a second pressurized containers (A, B).
[0020] Said first and second pressurized containers (A, B), are held in place by means of dome-shaped members ( 15 , 16 ) of the housing ( 1 ), as shown in the attached figures. A first and a second levels ( 11 , 12 ) are pivotally arranged in said dome-shaped members ( 15 , 16 ) for actuating respectively on the spray valves for spraying an amount of atomized liquid thorough the aerosol nozzles ( 13 , 14 ).
[0021] A cam element ( 5 ) is pivotally mounted in a cylindrical finger ( 23 ) protruding from an inner face of one of the parts of the housing ( 1 ). The cam element ( 2 ) has a T-shaped configuration, formed by a left arm ( 4 ), a right arm ( 3 ) and a central arm ( 5 ).
[0022] The cam element ( 2 ) is pivotally mounted in the cylindrical finger ( 23 ), which defines a pivot point located in the longitudinal axis of the central arm ( 5 ).
[0023] Furthermore, the cam element ( 2 ) is shaped and dimensioned so as to activate the spray valve of the container (A) or the spray valve of the container (B).
[0024] A DC electric engine ( 6 ) having a driven shaft ( 7 ), is operatively engaged with said cam element for operating said cam element, so that the rotation of the shaft ( 7 ) in a clock-wise direction as observed in FIG. 1 , would cause the can element ( 2 ) to pivot to the right and the activation of the second level ( 22 ). The rotation of the shaft ( 7 ) in anti-clock wise direction, would cause the cam element to pivot to the left and the activation of the first level ( 21 ).
[0025] For the activation of the spray valves, the free ends of the arms ( 3 , 4 ) contact respectively with the levels ( 11 , 12 ) which in turn press down the spray valves. The levels ( 11 , 12 ) convert respectively the rotational movement of the arms ( 2 , 3 ), into a longitudinal movement which is applied to the spray valves, for that the damage of the valves is avoided.
[0026] The levels ( 11 , 12 ) are dimensioned for reaching the spray valves inside the dome-shaped members ( 15 , 16 ).
[0027] The drive shaft ( 7 ) of the engine ( 6 ) is operatively engaged with the central arm ( 5 ) of the cam element ( 2 ) by means of speed reduction gears ( 8 , 9 , 10 ) in a known manner. For that purpose, the free end ( 17 ) of the central arm ( 5 ) has a toothed configuration and one of said reduction gear is meshed with said free end as shown in FIG. 3 .
[0028] The device of the invention further comprises an electronic circuit ( 19 ), which includes and electronic timer, for example implemented by programmable electronic means, which are associated to the electric engine ( 6 ) to command its operation. The device also comprises electronic means connected to the terminals of the electric motor for changing the rotation direction of the drive shaft.
[0029] In an automatic operation of the device, said electronic means will operate the electric engine at predetermined periods of time set by a program, and in such a manner that the shaft of the engine will rotate in the required direction in order to activate a selected spray valve according to a programmed sequence.
[0030] In a preferred embodiment, the two spray valves are operated alternatively in order to spray two different perfumes in a room.
[0031] Different programs can be stored in the electronic means, which can be selected by the users. Also, the user can manually command the activation of one of the spray valves as desired.
[0032] Due to the T-shaped configuration of the cam element, the speed reduction gears and the engine can be located in between the space provided in the device for receiving said containers, for that the use of the volume inside the casing is optimized obtaining a compact device.
[0033] Additionally, due to the T-shaped configuration of the cam element, the torque applied by the reduction gears can be increased without stressing the teeth of the gears.
[0034] In a preferred embodiment, the spray valves are metered valves that liberates a determined amount of volatile substance independently of the duration of the activation of the valve by the cam element. | The present invention refers to an automatic dispenser for periodically spraying an amount of liquid from two aerosol containers. (A, B) Preferably the two aerosol containers (A. B) contain liquid of different nature, such as different perfume or active substance composition, so that the same device is capable of dispensing alternatively two or more different substances. | 1 |
This is a continuation of application Ser. No. 798,960, filed May 20, 1977, now abandoned.
BACKGROUND OF THE INVENTION
This invention generally relates to compact dispensing packages for sheet-like products. In particular, this invention relates to compact dispensing packages having a discrete support member. Still more particularly, this invention relates to compact dispensing packages having an inverted Y-shaped support member.
In compact dispensing packages, the sheet-like products are folded into a bundle which may be supported, as taught in U.S. Pat. No. 3,881,632 issued to Allen D. Early et al. on May 6, 1975, or unsupported, as taught in U.S. Pat. No. 3,369,700 issued to Howard N. Nelson on Feb. 20, 1968. The bundles are generally formed into the shape of an inverted U although other configurations are known and used by those skilled in the art.
Various methods and devices for supporting the bundle are also known in the art. U.S. Pat. No. 1,657,942 issued to Louis C. Spaldo on Jan. 31, 1928 and U.S. Pat. No. 3,456,843 issued to Thomas H. Planner on July 22, 1969, each teach a tissue bundle supported by the outer wall of the carton which is formed into an upwardly projecting partition. U.S. Pat. No. 3,209,941 issued to Kenneth V. Krake on Oct. 5, 1965 teaches an inverted U-shaped tissue bundle also supported by an upwardly projecting partition formed from the outer wall of the carton. Krake, however, further teaches a separate insert placed atop the partition to maintain the stability of the carton. Further, U.S. Pat. No. 3,243,079 issued to Forrest R. Rettmer teaches a V folded bundle supported by a discrete insert positioned within the carton.
During the manufacture of a supported bundle, the individual sheets of sheet-like product are interleaved and stacked and the blank from which the unfolded support member is formed is placed atop the stack prior to being folded and placed into the carton. To prevent shifting and to keep the sheet-like product essentially centered with respect to the support member the blank is substantially coextensive with the sheet-like product. Thus, the length of the blank can be neither substantially longer nor shorter than the length of the sheet-like product.
After being folded and inserted into the package the bundle is held in dispensing position by the support member. If the length of the support member is too short relative to the diagonal dimension of the package, however, the bundle will not be adequately supported and will be susceptible to displacement during transit or rough handling. The length of the support member is fixed by the length of the tissue and the diagonal dimension of the package is fixed by the packaging machine, and neither parameter may be changed without unfavorable consequences. Specifically, changing the length of the support member could result in the sheet-like product shifting to an off-center position relative to the support member thus preventing the sheets from being dispensed properly and changing the diagonal dimension of the package could increase manufacturing costs by causing packing machines to be redesigned.
The prior art stack support members lack the aspects of the present invention whereby an outwardly projecting protuberence increases the length of the folded insert thereby providing improved stability of the sheet material bundle.
Accordingly, it is an object of the present invention to provide a compact dispensing package having a support member with improved stability.
An additional object of the present invention is to provide a bundle support member having outwardly projecting protuberences.
A further object of the present invention is to provide a bundle support member having a length greater than the length of the blank from which it is formed.
SUMMARY OF THE INVENTION
In a compact dispensing package for sheet-like materials, the individual sheets are generally interleaved, U-folded, and supported by a bundle support member. According to the present invention, the bundle support member is provided with outwardly projecting protuberences thereby increasing the length of the support member without increasing the length of the blank from which the support member is formed.
In one preferred embodiment of the invention, a plurality of semi-circles are cut in the blank such that the diameter of the semi-circle and the medial fold line of the blank are coincident. When the blank is folded along the medial fold line the semi-circles project outwardly from the upper edge thus formed in the bundle support member thereby providing a bundle support member having a longer length than the blank from which it was formed.
The longer the length of the bundle support member the greater the stability of the bundle. A bundle support member having the protuberances of the present invention, therefore, will provide more resistance to bundle shifting than a bundle support member formed from the same length blank but not having the protuberance.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partially cut away perspective view of a compact dispensing package embodying the present invention.
FIG. 2 is a plan view of a carton-board blank prior to being folded to form a bundle support member.
FIG. 3 is an exploded side view of the bundle support member of the present invention and a U-shaped bundle of sheet-like product.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the figures, there is shown a preferred embodiment of the present invention as it would be used in a compact dispensing package for facial tissues. It should be understood, however, that the present invention is broadly applicable to the art of dispensing packages for sheet-like products. As used herein the term "sheet-like products" refers to products which are thin relative to their breadth and length and which are substantially flaccid and flexible. Further, as used herein, the term "compact dispensing package" refers to packages intended to contain a plurality of interleaved sheets of a sheet-like product in a folded configuration such that pop up dispensing of the successive sheets is facilitated.
As best seen in FIG. 1, a preferred compact dispensing package 12 basically basically comprises a bundle support member 10, a carton 13, and a bundle 26 of sheets 28 of a sheet-like product. Carton 13 is preferably formed from cardboard into a form sustaining, somewhat cubical shape having a front wall 14, a back wall 16, side walls (not shown), top wall 18, and bottom wall 20. Top wall 18 has an elongated aperture 24 centrally disposed therein. A suitable compact dispensing package is described in U.S. Pat. No. 3,881,632 issued to Allen D. Early on May 6, 1975 which patent is herein incorporated by reference.
Carton 13 contains a plurality of sheets 28 of a sheet-like product, such as facial tissues, which are folded to form bundle 26. Bundle 26 is preferably folded into a U-shape although other configurations such as a V-shape may also be used. Sheets 28 of bundle 26 are interleaved to promote pop-up dispensing in any manner well known in the prior art. A suitable interleaving fold arrangement is described in the aforementioned U.S. Pat. No. 3,881,632.
Bundle 26 is held in dispensing position in carton 13 by bundle support member 10. Dispensing position is that position which permits uppermost sheet 28 to be pulled through aperture 24 successively in a pop-up fashion. Bundle support member 10 has a stem 30 with an upper edge 32 and a lower edge 34 hingedly affixed to arms 36 and 38.
In the preferred embodiment of FIG. 1, support member 10 assumes an inverted Y-shaped configuration when inserted into carton 13 with upper edge 32 of stem 30 projecting toward top wall 18 and essentially centered about apeture 24. In this position, carton 13 is divided into a triangular cross-section tubular void 40 disposed between arms 36 and 38 and bottom wall 20 and a bundle accomodating space 42 disposed between member 10 and front, back, and top walls 14, 16, and 18 respectively of carton 13.
FIG. 2 is a plan view of a rectangular carton board blank 44 having a length "L" from which member 10 is formed. Blank 44 is provided with a medial fold line 46 and two intermediate fold lines 48 and 50. The fold lines 46, 48 and 50 divide blank 44 into four rectangular areas which are hereby designated arm portions 52 and 54 and stem portions 56 and 58. When blank 44 is folded to form support member 10 having an inverted Y-shaped configuration (shown in FIG. 1) it is folded in such a manner that it has substantially no residual resilience so that it will not pinch bundle 26 of sheets 28 between the upper edge 32 of support member 10 and top wall 18 of carton 13. Otherwise, if the support member 10 has substantial resilience acting outwardly on bundle 26, dispensing, particularly intitial dispensing, would be difficult and perhaps result in tearing one or more sheets 28. Furthermore, if a plurality of closely spaced medial fold lines are provided, the positioning of each blank with respect to folding devices becomes less critical.
At least one and preferably a plurality of tabs 60 having an inward side 62 are cut in stem portions 56 and 58 such that inward side 62 is uncut and essentially coincident with medial fold line 46. Tabs 60 may be cut in either stem portion 56 or 58 and are preferably cut alternatively in both stem portions 56 and 58. In the preferred embodiment tabs 60 are semicircular with inward side 62 being the diameter. Other configurations for tabs 60 may be used, such as parabolic or hyperbolic shapes, but it is preferable that tabs 60 have no sharp corners in order to prevent binding between tabs 60 and bundle 26. The length "l" of tabs 60 is measured perpendicularly from medial fold line 46 to the farthest point of tab 60.
Sheets 28 are interleaved and stacked with blank 44 being placed on top of the stack prior to being folded into bundle 26 and inserted into carton 13. To ensure that sheets 28 are centered relative to blank 44 (i.e., the centerline of sheet 28 and medial fold line 46 of blank 44 are coincident) the external dimensions of blank 44 are substantially coextensive with the external dimensions of sheets 28. Thus, the length L of blank 44 is substantially equal to the length of sheets 28.
Blank 44 is folded to form bundle support member 10 as shown in FIG. 3 in the following manner. Blank 44 is folded along medial fold line 46 with stem portions 56 and 58 being placed in face-to-face relationship thereby forming stem 30 and upper edge 32. Arms 36 and 38 and lower edge 34 are formed by folding blank 44 along intermediate fold lines 48 and 50. When blank 44 is folded along medial fold line 46, tabs 60 will project outward from upper edge 32 forming outwardly projecting protuberance 64. The height "h" which protuberence 64 extends beyond upper edge 32 is determined by and is equal to the length "l" of tab 60. The length of member 10 is measured along upper surface 66 and is longer than length "L" of blank 44 by twice height "h". The greater the height h the greater the stability and resistance to shifting of bundle 26. The maximum height "h" which is permissible is determined in accordance with the following formula:
h<H-t-S-Y
where:
H=height of carton 13 (See FIG. 1)
S=length of stem 30
Y=perpendicular distance between lower edge 34 and bottom wall 20.
A representative example of the preferred embodiment of compact dispensing package 12 comprises a carton 13 having a height H, width W and breadth B of 5.5 inches, (14 cm), 4.375 inches (11.2 cm), and 4.375 inches (11.2 cm) respectively, a bundle 26 comprising about 125 two-ply sheets of facial tissue which bundle has an uncompressed thickness t of approximately 1.75 inches (4.45 cm), the sheets 28 each being approximately 9.6 inches (24.5 cm) long by 4.12 inches (10.5 cm) wide being U-folded about the trasverse center line and being interleaved with each other to promote pop-up dispensing. In this example, member 10 is formed from blank 44 having a length L of 9.6 inches (24.5 cm) a width of 4.25 inches (10.8 cm) and is provided with fold lines 46, 48, and 50 to divide blank 44 into arm portions 52 and 54 having lengths of about 2.375 inches (6 cm) each and stem portions 56 and 58 having lengths of about 2.437 inches (6.2 cm) each. Three semicircular tabs 60 are cut in blank 44 such that two tabs 60 are cut in stem portion 56 and one tab 60 is cut in stem portion 58. The diameter of tabs 60 is approximately 0.50 inches (1.2 cm) and is coincident with medial fold line 46. Thus, height h of protuberances 64 is 0.25 inches (0.6 cm).
In this representative example of the present invention, carton 13, member 10, and bundle 26 are so configured that the bundle substantially fills the bundle accomodating space 42 without binding sheets 28 of bundle 26. Bundle 26 is supported so that the first sheet can be grasped and withdrawn, by extending a thumb and forefinger through aperture 24.
The present invention may, of course, be practiced other than as specifically described as the preferred embodiment. For example member 10 may assume an inverted T-shape when inserted into carton 13. Obviously, there are many other variations and modifications of the present invention which may be effected in the preferred embodiment without departing from the scope and spirit of the invention. | A compact dispensing package for sheet-like products having an improved stack support member with outwardly projecting protuberences. The stack support member is formed from a cardboard blank having essentially the same unfolded length as the sheet-like product contained in the dispensing package, but having a folded length greater than the sheet-like product. The increased length provides better stability for the bundle of sheet-like product during shipping and storage of the compact dispensing package. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. §119 to provisional application U.S. Ser. No. 61/978,430 filed Apr. 11, 2014, all of which is herein incorporated by reference in their entirety.
FIELD OF THE INVENTION
The present invention relates to the fields of eyewear and eyeglasses and the term eyewear shall be used to represent all known eyewear, including sunglasses, visual acuity correcting eyeglasses, safety eyewear and all other eyewear that are commonly used. More specifically, the invention relates to device(s) that can be adjusted in situ to allow stabilizing and maintaining the position of eyewear on the user. It can also be used in conjunction with a retainer strap and/or be integrated with a retainer strap. Lastly it can be integrated into the manufacture of eyewear. The present invention provides devices and methods of employing these novel elements.
BACKGROUND OF THE INVENTION
Various commercial products and/or patents are available for stabilizing and maintaining the position of eyewear on a user. These references can be separated into several classes: 1. tubular cylindrical devices that are added to temples to retain glasses on a user; 2. tubular cylindrical devices added to temples that include a curved retainer that is positioned behind a user's ears; 3. curved discs that fit onto temples and are positioned around the mastoid bone; and 4. hybrid adjustable retainer straps that prevent eyewear from falling off a user and contain elements of devices that maintain the position of eyewear on a user, such as tubular cylindrical elements with or without curved elements.
U.S. Patents relevant to the first class of using tubular cylindrical devices to stabilize and maintain position of eyewear include U.S. Pat. Nos. 2,626,538; 5,002,381; 5,054,903; 8,733,926; and U.S. Patent Application 2005/0286013. They show an ear contact tubular or cylindrical element that can slide onto the temple(s) of eyewear to preclude slippage of eyewear forward and downward on a user's nose and face. All involve a non-adjustable one size radius tubular concentric device intended to maintain interference fitment between the user's head and the temples containing the tubular device. If the size is not correct for optimal interference fitment, the tubular device would have to substitutes for one with a different radius for optimal interference fitment. U.S. Pat. No. 5,054,903 shows another example of a tubular segment on a temple to prevent slippage of the glasses forward on a user's nose and face. The tubular segment is positioned in a recess to keep it in place from moving forward or backwards. This invention also lacks the ability to increase the radius of the tubular segment in situ without exchanging to a different radius-sized tubular segment. U.S. Pat. No. 8,733,926 shows a cylindrical or other shaped columns, such as hexagonal, rectangular or square prisms, to fit onto the distal ends of temples of eyewear. It teaches a column that fits on the distal ends of the temples and includes a channel that is located at the center of the column, and does not teach off-centered channels, such as an eccentric shape with different radii that could be rotated on temples to obtain the best radius of the column for optimal interference fitment of temples on a user. A single radius cylinder or column located on eyewear temples may not retain the eyewear from moving forward because the connecting means located between temples and the eyewear lens component, have lateral movement capability to permit eyewear to be worn for users with different head sizes. As a consequence the single radius of a concentric column or column device placed on the eyewear temple may not allow adequate interference fitment of the eyewear on a user. Moreover a single radius cylinder or column on eyewear temples are often positioned on the upper ledge of the ear between the user's head and pinnae. There is less interference fitment means to retain the eyewear in that location and additionally that location forces the pinnae laterally creating an unpleasant aesthetic appearance for a user.
The second class involves using a tubular part with a curved element placed on temples and are located behind a user's ears. U.S. Pat. Nos. 2,626,538; 6,000,795; and 6,450,640 describe examples of this class. The tubular contact member are designed with one diameter located on the temples and have a downward member that curves concavely to conform to the upper posterior surface of the base of the ear. In essence the tubular elements have one radius which precludes adjustment in situ to a different radius to improve contact between the user's head and the tubular element. In addition although the curved element holds the eyewear from moving forward away from a user's nose and face, it has a single radius that cannot be adjusted in situ to another more optimal radius to minimize anterior and/or lateral movement, and thereby stabilize and maintain the position of eyewear on a user. Moreover these devices do not provide easy pivoting means to permit superior eyewear positioning onto the top of a user's head or forehead and do not provide means to maintain and stabilize interference fitment of eyewear when positioned in that location.
The third class represented by U.S. Pat. No. 7,862,168 utilizes curved disc extensions attached to the distal ends of the temples where they are located onto the mastoid bones of the user. This device has one thickness/radius and cannot be switched in situ to a different thickness or radius to adjust for best fitment to preclude anterior or lateral movement of the eyewear on a user. Moreover these devices do not provide easy pivoting means to permit superior eyewear positioning onto the top of a user's head or forehead and do not provide means to maintain and stabilize interference fitment of eyewear when positioned in that location.
The fourth class are hybrid devices that stabilize and maintain position of eyewear in combination with adjustable retainer straps attached to temples which wrap around the posterior aspect of a user's head. U.S. Pat. No. 4,133,604 shows a retainer strap with a tubular element that fits onto temples. U.S. Pat. Nos. 4,657,364 and 5,002,381 have a curved element for positioning behind a user's ears and an adjustable retainer strap. U.S. Pat. Nos. 3,502,396; 3,879,804; 6,941,619; 7,399,079; and 7,845,795 all include a retainer strap that is adjustable to hold the eyewear tightly on the user's head. U.S. Pat. No. 4,133,604 has a tubular element with a retainer integrated onto it for slippage onto temples. U.S. Pat. No. 6,053,612 shows a tubular member on temples in combination with a retainer strap. U.S. Patent Application 2013/0077043 has a modular temple connecting accessory with a non-rotatable single radius temple element. The devices in this class teach a single radius cylindrical part that cannot change radius in situ to improve interference fitment with the user's head.
Despite the various products and/or patents known to stabilize and/or maintain the position of eyewear on a user, there remains a need for a device providing improved stabilization and adjustability. It is against this backdrop of products and written description that the present invention is set forth, notably overcoming the combined limitations of products in the state of the art.
It is an advantage of the invention to provide a device on eyewear that permits a user to adjust the device in situ, thereby stabilizing and maintaining the position of the eyewear on a user.
It is an advantage to provide a device on eyewear that can be adjusted by rotating the device in situ and/or move the device anteriorly or posteriorly on the temples to obtain an optimal radius interference fitment for maintaining contact between the user's head and the device, thereby stabilizing and maintaining the position of the eyewear on a user.
It is an advantage to provide a device on eyewear that will permit a user to exercise vigorously and reduce likelihood of eyewear from moving off from its optimal position on a user's head and nose.
It is an advantage to provide a device that will stabilize and maintain positioning of eyewear on a user when the eyewear is located on the user's nose, face and head or when the eyewear has been moved to the user's forehead or top of the head.
It is an advantage to provide a device that can stabilize and maintain user intended positions of eyewear on a user's nose, face and head or on top of a user's head or forehead and minimize dislocating from those intended positions.
It is advantage to provide a device on eyewear which can be integrated with a retainer strap and/or allow rotation of the device on temples without causing the retainer strap to curl on itself.
It is an advantage to include ridges and/or grooves and/or any roughened pattern on the exterior surface of device on eyewear to allow improved grip for the user to rotate or move the device in situ on the temples.
It is an advantage to add groves or gutter-like patterns onto the surface of the device that will allow water or perspiration beads to drain off or away from the device and thereby stabilize and maintain the position of eyewear on a user.
It is an advantage for a device to be integrated into eyewear temples thereby adding a multi-radius eccentric structure that can be rotated or moved laterally in situ on eyewear temples by a user to obtain the optimal radius interference fitment for maintaining contact between the user's head and the device.
Other objects, advantages and features of the present invention will become apparent from the following specification taken in conjunction with the accompanying drawings.
SUMMARY OF THE INVENTION
In an aspect, the present invention discloses novel devices capable of in-situ adjustment means to improve stabilizing and maintaining the position of eyewear on a user. In an aspect, the invention describes two in-situ adjustment means involving mound(s) that can be used alone or in combination. Both adjustment means rely on utilizing more than one radius of a mound that will permit in situ improved interference fitment of the eyewear on a user's head and thereby minimize displacement of the eyewear from a user. One adjustment means involves rotating a mound with more than one radius on temples. The other adjustment means provides for anterior/lateral advancement of a mound with incremental or different radii. Both allow the device to obtain the optimal radius interference fitment to preclude easy displacement of eyewear from a user.
The term in-situ in this application is used to describe an eyewear device(s) comprised of multi-radius mound(s) which can be adjusted on location, meaning the adjustment occurs without removing the mound device(s) from the eyewear. However, in some circumstances a user may elect to access a different radius of the multi-radius mound by first removing the mound from the eyewear, then reattaching the same mound to the eyewear so that a different mound radius can contact the user's head to optimize stabilizing and maintaining the position of eyewear on the user. Hence, the term in-situ has a broader definition for adjustment means in this application.
In an aspect, the present invention to stabilize and maintain positioning of eyewear on a user can: 1. be added as accessories to eyewear; 2. be integrated into eyewear manufacture; and 3. be integrated with a retainer strap.
While multiple applications and embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments for applications of the invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a frontal and side perspective of a user wearing eyewear with a multi-radius mound device located on the distal section of the temple(s), according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 2 shows a frontal and side perspective of a user having eyewear located on the top of the user's head, with the eyewear containing a multi-radius mound device on the distal section of the temple(s), according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 3 shows a cross section of a multi-radius mound according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 4 shows a cross section of a multi-radius mound with circumferential longitudinal ridges and troughs, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 5 shows cross section of a multi-radius mound with flat sides, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user
FIG. 6 shows a top perspective of a retainer strap with clamping means at its ends for attachment into multi-radius mounds, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 7A shows a top and side perspective of a retainer strap with multi-radius mounds configured with a clamping means of the retainer strap, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 7B is an enlarged perspective of embodiment of a device in FIG. 7A comprised of a multi-radius mound-clamping means combination with the retainer strap for stabilizing and maintaining the position of eyewear on a use.
FIG. 7C is a cross section of the device comprised of a multi-radius mound-clamping means combination seen in FIG. 7A , according to an embodiment for stabilizing and maintaining the position of eyewear on a user.
FIG. 8 shows a longitudinal section of a rotating joint attaching between a multi-radius mound and a clamping means of a retainer strap, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 9 shows a frontal and side perspective of eyewear with a multi-radius mound with flat sides integrated onto temples, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 10 shows a frontal and side perspective of eyewear with a multi-radius cylindrical mound integrated onto temples, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 11 shows a frontal and side perspective of eyewear with integrating temple sections with an attached cylindrical multi-radius mound, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
FIG. 12 shows a frontal and top perspective of a portion of eyewear with integrating temple sections with an attached incremental multi-radius mound, according to an embodiment of a device for stabilizing and maintaining the position of eyewear on a user.
Various embodiments of the present invention will be described in detail with reference to the drawings, wherein like reference numerals represent like parts throughout the several views. Reference to various embodiments does not limit the scope of the invention. Figures represented herein are not limitations to the various embodiments according to the invention and are presented for exemplary illustration of the invention.
DETAILED DESCRIPTION OF THE INVENTION
In an aspect, the invention describes device(s) suitable for in situ adjustments. In a further aspect, the invention describes device(s) for stabilizing and maintaining the position of eyewear on a user.
The embodiments of this invention are not limited to the particular embodiments of the devices depicted, which can vary and are understood by skilled artisans. It is further to be understood that all terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting in any manner or scope. For example, as used in this specification and the appended claims, the singular forms “a,” “an” and “the” can also include plural referents unless the content clearly indicates otherwise.
The devices of the present invention may comprise, consist essentially of, or consist of the components described herein as well as other components and elements. As used herein, “consisting essentially of” means that the device may include additional components, but only if the additional components do not materially alter the basic and novel characteristics of the claimed devices. It should also be noted that, as used in this specification and the appended claims, the term “configured” describes a device that is constructed or configured to perform a particular task or adopt a particular configuration. The term “configured” can be used interchangeably with other similar phrases such as arranged and configured, constructed and arranged, adapted and configured, adapted, constructed, manufactured and arranged, and the like.
Eyewear 14 , as depicted in FIG. 1 , have a rigid or semi-rigid housing 15 comprising a bridge 17 that arches above and/or over a user's nose. It can contain structure with or without rims to contain a clear rigid or semi-rigid translucent barrier, such as lenses to overlay user's eyes. There are some eyewear without lenses and some rimless eyewear with lenses, but all have a bridge 17 and housing 15 . Most eyewear include nose pads 18 or a saddle bridge (not shown) that are part of the housing 15 that contact the top sides of the user's nose. There are also temples 16 , sometimes referred to as stems, connected to and are part of the housing 15 , which position eyewear onto the superior ledge of a user's ears between the pinnae and lateral aspect of a user's head. The temples 16 have spring, joint or other flexible attaching mechanisms with the housing 15 to permit lateral and medial spread for optimal fitment of the eyewear onto the user's head, ears, nose and face. However an omnipresent problem exists for many users in that eyewear fitment is often loose and can cause slippage of the eyewear from the user.
A compressible cylindrical mound, referred to as mound 19 , is added onto the temples 16 of eyewear, FIGS. 1 and 2 . In this example the mound 19 can be made of a compressible material (such as for example polyurethane; thermoplastics; neoprene; silicone) or other comparable materials. The mound 19 has a channel 21 seen in cross sections, FIGS. 3 , 4 , and 5 , which allow mound 19 to be slipped over and onto the distal temple section 42 . As referred to herein, the distal portion 42 or section of an eyeglass temple refers to the portion close to the center of the temple to the end of the temple (i.e. portion away from the point of attachment of the temple to the eyeglass housing 15 ). The interior of channel 21 can have inward protrusions or ridges 24 that minimize movement of the mound 19 on the temples and thereby inadvertent rotation of the mound 19 on the temple 16 or inadvertent anterior and/or posterior movement on the temples 16 . The mound 19 can also have longitudinal slits (not shown) that permit attaching the mound 19 sideways onto temples 16 , especially for eyewear with large sculptured temple ends that preclude slipping the mound 19 onto the temples 16 . As such the longitudinal slits allow positioning of the mound 19 over the temples 16 , and the mound 19 has the capacity to self-enclose around the temples 16 due to the inherent compressibility of the mound material to reform to its original shape. Mounds 19 can be also made from textile material with Velcro attachments to wrap around the temples. Means for attachment are not limited to the examples described herein.
When positioned correctly, the mound 19 on the distal section 42 of temples 16 creates an interference fitment with the lateral-posterior bone structure of the user's head, such as on the mastoid and/or the occipital bone(s). The contact interference fitment of the mound 19 with the user's head will be located slightly posterior and superior to the superior ledge of the external ear. However due to different configurations of temples and user's heads, the interference fitment can occur anywhere in contact to and/or close to and/or posterior to the user's ears.
The mound 19 added to the temples 16 can have different configurations and has more than one radius to accomplish in situ stabilizing and maintaining the position of eyewear on a user. The radius can be varied by simply rotating the mound 19 on the temples 16 . FIG. 3 shows a cross section of a mound 19 embodiment with an eccentric shape having a channel 21 through it for slipping onto the distal temple section 42 . As referred to herein, eccentric shall be understood to refer to a configuration having more than one radius, such that the channel 21 is away from the center or central axis of the mound 19 . In this non-limiting example, one radius 22 surrounding the channel 21 is wider compared to a smaller radius on the other side 23 that surrounds channel 21 . The radius of the mound is measured from the exterior circumference of the mound 19 to the lateral edge of channel 21 . Rotating the mound 19 would allow in situ change in the radius to allow for optimal interference fitment of the device with the user's head to stabilize and maintain the position of eyewear on the user. Moreover the user can also remove the mound 19 , and then reattach the same mound onto the distal temple section 42 so that a different radius can contact the user's head. In addition, FIG. 4 , shows a cross section of a mound 19 with longitudinal ridges 25 on the perimeter that allow easier gripping to rotate the mound 19 on the temples. The mound 19 can also have small ridges or protrusions 24 located on the internal surface of channel 21 to help improve grip of the mound 19 when it is attached to temple(s) 16 . Additionally there can be diagonal gutters (not shown) on the external circumference of the mound 19 between the ridges that allow perspiration beads or water to drain away from the mound 19 .
In another non-limiting embodiment of the device as seen in FIG. 5 , the cross section of the eccentric mound 19 has flat sides 26 with different radii (R 1 , R 2 , and R 3 ) measured from the flat side to the lateral edge of the channel 21 . Each radius width of R 1 , R 2 , and R 3 allows user to rotate the mound 19 on the temple ends 42 to obtain the best interference fitment of the temples on the user's head. The flat sides 26 allow for increased contact surface of the mound to the user's head. Moreover flat sides allow the user to recognize when another radius of the mound 19 has been rotated into a functional position.
Other geometric mound shapes can be used to rotate the mound 19 circumferentially to obtain an optimal radius for interference fitment on the use's head. A circumferential cylindrical shape could be reduced to almost a ring shape (not shown) with eccentric radii. The mound shapes must not impede in the ability to rotate different radiuses on the temple to allow optimal interference fitment against the user's head. In a preferred embodiment, the rotational capacity should be 360 degrees to allow the user to rotate the mound 19 circumferentially clockwise or counterclockwise to obtain the radius that permits the best interference fitment between the user's head and the mound 19 . However less than a 360 degree circumferential rotation can be designed with an eccentric mound 19 and still obtain the best radius interference fitment for the mound against the user's head. However if any shape is used it must be first, a functional shape that permits comfortable contact between the mound 19 and the user's head, and secondly be a shape that doesn't impair rotation to allow other radii to interpose between the user's head and mound 19 .
Beneficially, the mound 19 can be retained in place even if the eyewear gets wet from water related activities, from rain or from perspiration, such as during vigorous exercise. This occurs because of any or all of the following reasons: 1. optimizing contact of the mound 19 with the user's head by rotating the mound to obtain the radius that achieves a comfortable interference fitment of the temples with user's head; and, 2. the mound can have grooves or gutters on its external surface which permit water to drain away similar to the effect created by automobile tire tread.
The optimal interference fitment also minimizes eyewear from slipping down the user's nose and face in multi-vectored directions, especially anteriorly, inferiorly and laterally, and thereby maintains the proper positioning of lenses on a user to maintain ideal visual acuity.
In another embodiment, FIG. 12 , the mound 19 can have step-up or transitional incremental sized radii 43 circumferentially, that are ideally located on one side of the mound 19 , with the smallest to the largest radius emanating from its anterior end toward its posterior end. As noted, each radius may be slightly larger than the preceding anterior one. The user places the mound 19 onto the medial aspect of the distal section 42 of temples and then moves the mound 19 laterally, anteriorly and/or posteriorly, on the distal section 42 to allow an optimal radius to contact the user's head and thereby improve interference fitment against the head. The full length of the mound 19 can be short enough to preclude the mound 19 from moving onto the upper ledge of the ears which will cause the pinnae to distort laterally. The different radii for this mound 19 embodiment can be transitionally incremental or non-transitionally incremental.
The previously described rotating radius adjustment means and the incremental radius adjustment means of the mound 19 can be manufactured in combination or made so that each adjustment means can exist by itself. The posterior end of the mound 19 can be closed off so the mound 19 cannot be moved too far anteriorly to preclude its ability to create an interference fitment. However, this could preclude using the full anterior adjustment means of the mound 19 with incremental radiuses 43 . It is also understood that the mound 19 could have incremental radiuses 43 located 360 degrees around the entire circumference of the mound 19 , so that the user simply advances the mound anteriorly on the distal section 42 of temple(s) 16 to achieve the best interference fitment as described. However the aesthetic effect of the larger radii being visible on the lateral side of the mound 19 may not be as pleasing compared to having the incremental radii located on the medial side of the mound 19 where they would not be easily visible.
As seen in FIG. 2 , the multi-radius mound 19 device provides yet another advantage to stabilize and maintain positioning of eyewear when the user positions the eyewear on the top of the head or on the forehead (not shown). The interference fitment of the mound 19 in contact with the user's lateral posterior side of head provides a pivotal means to permit the user to move the eyewear up onto the top of the head or forehead without displacing the eyewear off the user's head. Often for example, an eyewear user will need to move the eyewear off the nose up onto the forehead or top of the head to read something that might be blurred with corrective lenses. The interference fitment by the mound 19 provides pivoting means for the user to easily move the eyewear back to its original position on the user's head and nose. The multi-radius mound 19 minimizes anterior, lateral and inferior displacement when the eyewear is positioned in a first position on the user's nose and face, and it allows the eyewear to pivot to a superior second position on the top of the user's head or forehead and minimizes further superior-anterior displacement when positioned at that location.
It is possible to integrate a retainer strap 40 with or without a tightening means 38 , such as the commercially available Croakie® retainer straps, in combination with the mound 19 , as shown in FIG. 6 . In this embodiment the distal end 31 of the mound 19 would have a channel 21 large enough to fit over clamping means 37 . The proximal end 32 of the mound 19 would then attach onto the distal temple section 42 . Although this integration can be achieved, it should be noted that the rotating capability of the mound 19 could cause the retainer strap 40 to curl up on itself. To avoid this problem, FIG. 8 , shows an embodiment with a ball and socket joint 30 formed between the distal end(s) of the mound 31 and the clamping means 37 of the retainer strap 40 which normally attaches to the distal section 42 of the temples 16 . The ball and socket joint 30 is comprised of two parts using a semi-rigid or rigid plastic. One part has a ball shape 27 and a proximal end 28 that fits into the distal end 31 of the mound 19 that projects off and distally away from the distal temple section 16 . The second part is comprised of a socket 29 that fits around the ball 27 and has a distal end 33 that allows fitment into the clamping means 37 of the retainer strap 40 . The ball and socket joint 30 can be assembled as one piece or be separate parts, and are attached between the mound 19 and the retainer strap 40 . When the retainer strap 40 is attached to the mound 19 via this ball-socket joint 30 , rotation of the mound(s) 19 on the temple(s) 16 would occur independently of the retainer strap 40 , so that the latter does not curl up on itself. Other designs known to those familiar with rotating joints could be incorporated to achieve the same function as described herein, and/or other materials capable of allowing free independent rotation of the mound 19 in relation to a stationary retainer strap 40 .
In another embodiment of a retainer strap 40 in combination with a mound 19 , the clamping means 37 shown in FIG. 6 , that attaches the retainer strap 40 to the distal section 42 of temple(s) 16 , can be configured as one entity combined with a mound 37 having multi-radii (R 4 , R 5 and R 6 ), FIGS. 7A , 7 B and 7 C. This multi-radius mound-clamping means (abbreviated MRMCM) 37 embodiment is seen in cross section, FIG. 7C with two channels seen A and B, and channel 21 for attachment onto distal temple section 42 . In a normal commercially available retainer 40 with clamping means seen in FIG. 6 , radiuses R 4 are the same and sit in channel A for attachment of the clamping means 37 with a retainer strap 40 to the distal section 42 of temple(s) 16 . In FIG. 7C there are two additional different radiuses, R 5 and R 6 , that sit in channel B when placed onto the distal section 42 of the temples. Once the MRMCM 37 is attached to the distal section 42 of the temple(s) 16 into channel A, the eyewear is then positioned in its normal use position on the user at a location near the occipital-mastoid region of the user's head with R 4 contacting the user's head. When viewing posteriorly on the right side of user's head, clockwise rotation of the MRMCM 37 in FIG. 7C moves it from channel A to channel B on the distal section 42 of temples causing radius R 5 to engage the user's head. If radius R 5 does not allow for optimal interference fitment, counterclockwise rotation of MRMCM 37 will move it back into its original position in channel A, and then the user can continue to rotate it counterclockwise into channel B to access radius R 6 . Although rotation of the MRMCM 37 can cause some curling of the retainer strap 40 , it is minimal as there is a maximum 90 degree clockwise or counterclockwise rotation from the normal position of the MRMCM 37 out of channel A to sit either R 5 or R 6 into place. It is also possible in a further embodiment to have extra different radii added to the medial and lateral sides instead of to the inferior and superior sides as with the MRMCM 37 embodiment, but access to each radius will require a maximum 180 degrees rotation which causes more curling of the retainer strap. It is possible in a further embodiment to include a rotational joint means as shown in FIG. 8 connecting the MRMCM 37 to retainer strap 40 to minimize curling of the retainer strap 40 when MRMCM 37 is rotated in situ. In essence these embodiments have two functions: 1. optimizes interference fitment with the user's head which will stabilize and maintain the eyewear on a user; 2. has the added protection of protecting the eyewear from falling off a user if displaced from a user's head.
Although not shown the MRMCM 37 could have incremental radii (seen in FIG. 12 ) located from its anterior to posterior end, so that it could not only be rotated on the distal section 42 of the temple but it could be moved slightly anteriorly on the distal section 42 of the temples to obtain optimal interference fitment with the user's head. It is understood that either rotational adjustment and/or anterior/lateral adjustment means could be separately configured or combined with a retainer strap 40 .
A typical commercial clamping means 37 in FIG. 6 of a retainer strap is traditionally shaped as a rectangle with the same radii on the medial and lateral sides that contact around the user's ears and different but same radii on the superior and inferior sides. These clamping means have one channel for setting onto the distal section 42 of temples(s) and are not intended or designed for rotation on the distal section 42 of temples. Hence even though these commercial clamping means 37 may have two radiuses, one that is the same on the superior and inferior sides and a second different one that is the same on the medial and lateral sides, they do not have the internal structure for setting different radii into a second channel to maintain the clamping means 37 in place. They are designed only for a total of two radii instead of three or more in the aforementioned embodiment of MRMCM 37 .
Manufacturers of eyewear can integrate or add mounds having more than one radius to a separate distal section 42 of temple(s), FIG. 11 . The distal temple section 42 can have an attached mound 19 of any shape with more than one radius to approximate a user's head. The mounds 19 with different radii can have flat shape-like exteriors that approximate the user's head as described in the cross section of FIG. 5 or cylindrical eccentric shapes with different radii as seen in FIGS. 3 and 4 . The distal temple sections 42 can be integrated into one or more proximal temple sections 44 of eyewear. In one embodiment a distal temple section 42 with a smaller size can slide into a channel (not shown) in a proximal temple section 44 by a reversible or irreversible attaching means having a tight fitment lock. Other locking means, such as protrusions (not shown) in the distal temple section 42 can lock into openings (not shown) in the proximal temple section 44 . The protrusions and openings can be located on either distal or proximal temple sections. In this embodiment the eccentric multi-radius mound 19 can be rotated on the distal temple section 42 to achieve the optimal interference fitment as previously described. Other connecting means for distal 42 and proximal 44 temple sections known in the art can be used, such as with magnets.
FIG. 12 shows the mound 19 having transitional radii 43 starting with the smallest anteriorly to the largest posteriorly and located on the medial side of the distal temple section 42 . Sliding the distal temple section 42 into the proximal temple section 44 allows the user to move the distal temple section 42 anteriorly in relation to the user's head until the optimal interference fitment occurs between the mound radius and the user's lateral and posterior head region. In addition both temple sections 42 , 44 can be fully integrated with the mound 19 located on the distal temple section. The mound 19 with transitional radii 43 can then be moved anteriorly or posteriorly on integrated temple sections 42 , 44 to achieve the best interference fitment. The mound 19 on the distal temple section 42 can also be rotatable to allow optimal approximation of a mound radius with the user's head.
A non-rotatable multi-radius mound can also be integrated into the manufacture of the distal temple section 42 (not shown). For example, it is possible to manufacture a mound with more than one radius into the manufacture of temples. The multi-radius mound 19 would be positioned into a window formed in the wall of the distal temple section 42 . One side of the mound would expose a large radius on the lateral side of the temple and the medial side of the temple wall would expose a smaller radius of the mound. When the distal temple section 42 is integrated with a proximal temple section 44 , if the contacting radius of the mound 19 does not produce a good interference fitment, then the distal temple section 42 can be separated by reversing the attaching means from the proximal temple section 44 . This allows the user to flip over the temple to the contralateral side, so that radius of the mound becomes the medial side of the distal temple section 42 . Reattachment of the distal temple section 42 with the proximal temple section 44 then allows the previously contralateral mound radius to contact the user's head to provide improved interference fitment with the user's head. The positioning of the mound having two radii in this example could be set with a mound that does not have a channel as it could fit firmly into the stem window by mechanical interference fitment means. The mound would be configured so that one side has a larger radius protrusion in relation to the temple 40 and the other side would have a smaller protrusion radius. However an eccentric mound could have a channel with a slit, so that it would slip over and around a bar in the window or other similar configuration to position it in the window of the temple.
Another embodiment to integrate eccentric mounds 19 into temple manufacture are shown in FIGS. 9 and 10 . The distal section 42 of temples 16 can have a reduced circumference 41 terminating in an expanded end 42 A of the distal section 42 . Mounds 19 made of stretchable compressible materials can fit over the expanded end 42 A onto the reduced circumference 41 of the distal section 42 where they will be maintained in position by the fitment interference of the expanded end 42 A. The mounds 19 in FIG. 9 can have flat sides 26 approximating the user's head and can be rotated in situ for the user to recognize when a different radius has been rotated into head contact to obtain the best radius interference fitment for stabilizing and maintaining the position of eyewear on a user. It is also understood that mound 19 can have a cylindrical eccentric shape shown in FIG. 10 or any other previously mentioned functional eccentric shape.
All publications and patent applications in this specification are indicative of the level of ordinary skill in the art to which this invention pertains. All publications and patent applications are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated as incorporated by reference.
The inventions 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 inventions and all such modifications are intended to be included within the scope of the following claims. | Devices for eyewear and eyeglasses providing in situ adjustability to stabilize and maintain positioning of the eyewear and/or eyeglasses on a user are disclosed. The devices are further suitable for use in conjunction with a retainer strap and/or integrated with a retainer strap. The devices are further suitable for integration into the manufacture of eyewear and/or eyeglasses. Embodiments of the device and methods of employing the same are set forth. | 6 |
BACKGROUND OF THE INVENTION
This invention relates to a novel heat exchanger or quench cooler for quenching the effluent from a hydrocarbon cracking furnace. More particularly, the invention relates to the coupling between the cracking furnace tubes and the tubes of the quench cooler or transferline exchanger.
In the production of light olefins (ethylene, propylene, butadiene and butylenes) and associated aromatics (benzene, toluene, ethylbenzene, xylenes and styrene) by the thermal cracking of hydrocarbon feedstocks in the presence of steam, the cracking reactions are stopped by rapidly cooling or quenching the cracking furnace effluent. The quenching time is measured in milliseconds and has the purpose of "freezing" the furnace outlet composition at its momentary value to prevent degradation of the olefin yield through continuing secondary reactions. A number of different quench cooler designs are available in the marketplace depending upon the quantity of cracked gas to be cooled, the fouling tendencies of the furnace effluent and the pressure/temperature conditions of the steam to be generated. These designs range from conventional fixed tubesheet shell and tube heat exchangers to double pipe designs.
It is well known that for any given cracking furnace operating conditions, the yield of olefins can be maximized and quencher fouling minimized by decreasing the temperature of the gas leaving the cracking furnace as rapidly as possible. This requires that the quench cooler be positioned as close as possible to the cracking furnace outlet, that the volume of the inlet section of the quench cooler be minimized and that the surface to volume ratio in the cooling section be maximized. The latter requirement implies that a multiplicity of small quencher tubes are more favorable than a single large diameter arrangement.
One prior art type of quench cooler known as the SHG transferline exchanger (Schmidt'sche Heissdampf--Gesellschaft mbH) uses a multiplicity of double tube arrangements in parallel wherein each quench tube is surrounded by a concentric outer tube which carries the water-steam mixture. The annuli between the inner and outer tubes are supplied with boiler water through horizontal, oval-shaped headers. In this regard, see German Patentschrift DE 2551195. Another prior art patent which uses this double tube arrangement with an oval header for the outside tubes is U.S. Pat. No. 4,457,364. This patent discloses a distributor having an inlet for the gas from the furnace and two or three diverging branches forming a wye or tri-piece for the transition between the furnace and the quench cooler. As indicated, this transition where cooling has not yet begun can be critical in minimizing continued reaction and undesirable coke deposits. In this U.S. Pat. No. 4,457,364, the cross sectional area for flow through the connector is substantially uniform to achieve substantially constant gas velocity throughout the distributor. The distributor may also be divergent in cross sectional area up to the point where the ratio of the sum of the cross sectional areas of the branches to the cross sectional area of the inlet is 2:1.
In U.S. Pat. No. 5,464,057, the inlet section or connector for a quench cooler between the furnace outlet and the inlets to the quench cooler tubes splits the flow into a plurality of branches and is designed to reduce the inlet section residence time to a minimum. In order to uniformly distribute the gas to a plurality of in-line arranged quench tubes, the flow passages are configured to first efficiently decelerate the gas leaving the furnace and then re-accelerate the gas to the quencher cooling tube velocity. A conical diverging diffuser section in the connector decelerates the gases and then a tapered and branched converging section re-accelerates the gases as they are fed into the quench cooler tubes. The cross sectional transitions are smooth with monotonic area change in the flow direction (aerodynamic) so that dynamic pressure is recovered, dead spaces, i.e. zones of flow separation, are avoided and the pressure loss is minimal. Although such a connector is very effective, it is only adaptable to an in-line arrangement of quench tubes.
SUMMARY OF THE INVENTION
The present invention relates to the inlet section or connector for a quench cooler between the furnace outlet and the inlets to the quench cooler tubes. The quench cooler makes use of the double tube arrangement with an oval header for the outside tubes and with the plurality of quench tubes being arranged in a circular fashion. The connector provides a conical diffuser channel which decelerates the gases leaving the furnace and then provides a radial diffuser to direct the gases outwardly. The connector then provides for the smooth re-acceleration of the gases into the circular arrangement of cooling tubes at the working tube velocity.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a side elevation view of a quench cooler partially in cross-section incorporating the present invention.
FIG. 2 is a cross-sectional view of the quench cooler of FIG. 1 taken along line 2--2.
FIG. 3 is a perspective view of the connection of the tubes to and through the oval header.
FIG. 4 is a cross-section view of the outer section of the connector.
FIG. 5 is a cross-section view of the inner section of the connector.
FIG. 6 is a top view of the inner section of the connector taken along line 6--6 of FIG. 5.
FIG. 7 is a vertical cross-section view of a portion of the connector section of FIG. 5 taken along line 7--7.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, the quench cooler 10 comprises a plurality of double tube heat exchange elements 12 which in turn comprise the inner tubes 14 which carry the cracking furnace effluent gas surrounded by the outer tubes 16. The annulus between the two tubes carries the coolant water/steam mixture. The lower ends of the tubes 14 and 16 are connected to the oval header 18 while the upper ends are connected to a similar oval header.
The connection of the tubes to the oval headers is shown in detail in FIG. 3. The inner tubes 14 pass completely through the header while the outer tubes 16 terminate at the header and are open to the inside of the header. Cooling water, which is supplied to the lower header 18 via the coolant inlet header 20 and the radial coolant tubes 22, as shown in FIG. 1, flows through the lower header 18, into the annular space between the tubes and upwardly emptying into the upper header. The coolant, which is now a heated steam/water mixture, flows out from the upper header into the coolant outlet header 24. The cooled gas which is flowing up through the pipes 14, empties into the upper outlet chamber 26 and is discharged through the outlet 28.
The present invention is illustrated using an 18-tube arrangement which is best seen in FIG. 2. This figure shows the annular oval header 18 to which the elements 12 are connected. A plurality of the water inlet connections 22 are shown extending between the header 20 and the header 18. The water inlet to the header 20 is shown at 21.
The quench cooler of the present invention can be applied most advantageously with cracking furnaces (not illustrated) employing a relatively small number of high capacity cracking coils. For example, such a furnace might have six coils each 12 meters (40 feet) in height with each coil formed from a multiplicity of inlet tubes feeding into a single 16.5 cm (6.5 in.) internal diameter outlet tube. The effluent from one such coil can be quenched in a single quench cooler of the present invention. The quench cooler typically has sixteen or more quencher tubes.
The connecter 30 at the lower end of the quench cooler comprises a container 32 which forms the pressure boundary. A flange 34 around the edge of the container 32 is attached to the flange 36. The container 32 houses the components of the present invention which distribute the gases to the circular arrangement of tubes 14 and which provides the diffuser channels to decelerate and then accelerate the gases.
Inside of the container are the two sections 38 and 40 which cooperate to form the flow channels. These sections are shown in more detail in FIGS. 4 and 5. The lower portion of outside section 38 comprises an outwardly tapered conical diffuser region 42 such that the flow area increases and such that the upwardly flowing gases decelerate. The upper portion 44 of the section 38 cooperates with the section 40 to provide radial diffuser and accelerator regions. As shown in FIG. 1, the section 40 is mounted on and extends down inside of the section 38 so as to form the flow passages. The sections 38 and 40 are preferably formed from a hard ceramic such as fired alumina but could also be formed from other materials such as high alloy metal castings.
Located around the periphery of the section 40 is an annular ring portion 46. As shown in FIG. 6 which is a top view of the section 40, a plurality of holes 48 extend through this ring portion 46, one hole 48 for each tube 14. The holes 48 are located so as to be aligned with the tubes 14. The lower, outside surface 50 of the ring portion 46 engages the upper surface 52 of the section 38. There is a soft gasket between these two parts which allows for thermal expansion. There is no gasket between the connector and the tubes 14.
The two sections 38 and 40 are located in the container 32 as shown in FIG. 1 and then surrounded by the insulating castable refractory material 54 which fills the space between the sections 38 and 40 and the container 32.
When the connector is assembled as shown in FIG. 1, the gas passage comprises a diverging conical diffuser portion 56 followed by a radial diffuser section 57 which further increases the flow area. Although the height of the radial cross-sectional area of the radial diffuser section may not increase very much and in fact may decrease slightly, the circumferential cross-sectional area increases as the section extends out from the center because of the increased circumference. These diffuser portions 56 and 57 are then followed by a converging portion 58. The net effect is a smooth or monotonic convergence of the flow area. Discontinuities are avoided which would create eddies and coking. Therefore, the gases are first decelerated in the conical diffuser 56 and the radial diffuser 57 and then re-accelerated back up to the quencher tube velocity in the annular converging portion 58. The smooth re-acceleration serves to avoid flow separation thereby minimizing coke formation in dead zones while providing a uniform flow distribution to the individual quencher tubes. As a specific example, the inside diameter of the inlet tube may be 16.5 cm (6.5 in.) and the inside diameter of the outlet of the diffuser may be 22.0 cm (8.7 in.) for a ratio of flow area of 1.78. The flow area then increases further in the radial diffuser giving an overall diffuser area ratio (radial diffuser outlet to conical diffuser inlet of 4.9. The flow area then decreases as the gas accelerates into the annulus upstream of the tubes. A typical exchanger would have 18 tubes with an inside diameter of 4.8 cm (1.9 in.) giving a flow area 32 percent of that at the radial diffuser outlet.
Since the flow is re-accelerated without dead zones, coke deposition at the entrance to each tube is minimized. Even if coke is deposited in the tubes, deviation from uniform flow distribution is significantly reduced. This is the advantage of using an aerodynamically efficient diverging/converging passage instead of a conventional transfer line exchanger inlet. The result of applying the diverging/converging passage of the present invention is greatly reduced inlet residence time, uniform distribution, reduced coking tendencies and consequently improved yields and increased run length. | A quench cooler or transferline heat exchanger for quenching the effluent from a thermal cracking furnace has an inlet connector between the cracking furnace tubes and the tubes of the quench cooler. The tubes of the quench cooler are arranged in a circular pattern of spaced tubes. The flow passage of the connector is configured to initially decelerate and then re-accelerate the gas. This involves a conical diverging diffuser followed by a radial diffuser and then an annular converging section. The cross sectional transitions are smooth to avoid dead spaces and minimize pressure loss. | 2 |
[0001] This application is a divisional application of the application Ser. No. 14/048,008 field on Oct. 7, 2013, which is herein incorporated by reference.
BACKGROUND
[0002] Technical Field
[0003] The present invention relates to a method for manufacturing an electronic device, more particularly, to a method for manufacturing a semiconductor device.
[0004] Description of Related Art
[0005] Among semiconductor memory devices, dynamic random access memories (DRAMs) have been widely used. Generally, each cell of a DRAM has a MOS transistor which enables data charges in the storage capacitor to move in data read and write operations.
[0006] To be highly integrated, the DRAM should have a capacitor with a sufficient storage capacity and a small unit cell size. In particular, a general approach to reduce a production cost of DRAM is to increase an integration level. To improve an integration density of the DRAM cell, a unit cell size of the DRAM cell needs to be reduced. However, as a semiconductor device is shrunk, characteristics of the transistor of the semiconductor device are degraded by a short channel effect. To solve this issue, on one hand, various structures of planar transistor have been suggested to extend the channel length; however, there are still various concerns to limit it from manufacturing. On the other hand, vertical transistors have been suggested to solve the issue. A vertical transistor has doped source and drain regions, which are formed in a vertical direction, and thus a channel region is vertically formed in a substrate: however, it is difficult to control a body voltage in the vertical transistor having a channel region formed of an undoped silicon (Si) in the related art. Therefore, the vertical transistor has a difficulty in effectively controlling phenomena such as a punch-through effect or a floating body effect. That is, while the vertical transistor is not in operation, a gate induced drain leakage (GIDL) effect is caused due to holes accumulated in a body. Thereby, a current loss in the transistor frequently occurs and charges stored in a capacitor are drained so that a loss of original data is caused. Given the above, improvements in structural design of a semiconductor device h both planar and vertical transistors, and a method for manufacturing thereof are studied aggressively in this field.
SUMMARY
[0007] The present disclosure is to provide a semiconductor device and a method for fabricating the same, which reduce the short channel effect while the dimension of the transistor of the semiconductor device is reduced. Furthermore, the risk of short circuit of adjacent transistors is also avoided.
[0008] The present disclosure, in one aspect, relates to a method for fabricating a semiconductor device including the following steps. First, a substrate having at least one transistor is provided. A first insulation layer is formed to cover the transistor. The first insulation layer is patterned to form at least one opening, wherein a part of the transistor is exposed by the opening. At last, an epitaxy is formed in the opening to cover the part of the transistor.
[0009] According to one embodiment of the present disclosure, the method further comprises implanting the epitaxy to form a lightly doped epitaxy.
[0010] According to one embodiment of the present disclosure, the method further comprises fulfilling the opening with a conductive material.
[0011] According to one embodiment of the present disclosure, the first insulation layer s formed by chemical vapor deposition.
[0012] According to one embodiment of the present disclosure, before forming the epitaxy, the method further comprises forming a second insulating layer on the first insulation layer, and patterning the second insulation layer to form the opening, wherein the part of the transistor is exposed by the opening of the first and the second insulation layer.
[0013] According to one embodiment of the present disclosure, the second insulation layer is formed by chemical vapor deposition.
[0014] According to one embodiment of the present disclosure, the transistor is a vertical silicon pillar with a source electrode at the top of the vertical silicon pillar, a drain electrode at the bottom of the vertical silicon pillar, and a gate electrode substantially at the middle of the vertical silicon pillar, the source electrode is the part exposed by the opening and covered by the epitaxy.
[0015] According to one embodiment of the present disclosure, the transistor is a vertical silicon pillar with a drain electrode at the top of the vertical silicon pillar, a source electrode at the bottom of the vertical silicon pillar, and a gate electrode substantially at the middle of the vertical silicon pillar, the drain electrode is the part exposed by the opening and covered by the epitaxy.
[0016] According to one embodiment of the present disclosure, the transistor has a source, a drain and a gate electrode which are substantially coplanar, at least one of the source and drain electrode is the part exposed by the opening and covered by the epitaxy.
[0017] According to one embodiment of the present disclosure, the substrate is silicon and the epitaxy is epitaxial silicon.
[0018] The present disclosure, in another aspect, relates to a semiconductor device comprises at least one transistor disposed on a substrate, a first insulation layer, a epitaxy, and a conductive material. The first insulation layer is disposed on the substrate and covers the transistor, wherein the first insulation layer has an opening to expose a part of the transistor. The epitaxy is disposed in the bottom of the opening to covering the part of the transistor. The conductive material is disposed in and fulfills the opening, wherein the conductive material is electrically connected to the part of the transistor through the epitaxy, wherein the boundary of the epitaxy is adjacent to side alts of the opening.
[0019] According to one embodiment of the present disclosure, the top surface of the epitaxy is substantially flat.
[0020] According to one embodiment of the present disclosure, the transistor is a vertical silicon pillar with a drain electrode at the top of the vertical silicon pillar, a source electrode at the bottom of the vertical silicon pillar, and a gate electrode substantially at the middle of the vertical silicon pillar, the drain electrode is the part exposed by the opening and covered by the epitaxy.
[0021] According to one embodiment of the present disclosure, the transistor is a vertical silicon pillar with a source electrode at the top of the vertical silicon pillar, a drain electrode at the bottom of the vertical silicon pillar, and a gate electrode substantially at the middle of the vertical silicon pillar, the source electrode is the part exposed by the opening and covered by the epitaxy.
[0022] According to one embodiment of the present disclosure, the transistor has a source, a drain and a gate electrode which are substantially coplanar, at least one of the source and drain electrode is the part exposed by the opening and covered by the epitaxy.
[0023] According to one embodiment of the present disclosure, the first insulation layer comprises silicon oxide, silicon nitride, or combination thereof.
[0024] According to one embodiment of the present disclosure, the semiconductor device further comprises a second insulation layer disposed on the first insulation layer, wherein the second insulation layer has the opening to expose the part of the transistor.
[0025] According to one embodiment of the present disclosure, the second insulation layer comprises silicon oxide, silicon nitride, or a combination thereof.
[0026] According to one embodiment of the present disclosure, the conductive material comprises poly silicon, tungsten, titanium, titanium nitride, or a combination thereof.
[0027] According to one embodiment of the present disclosure, the substrate is silicon and the epitaxy is doped-epitaxial silicon.
[0028] In order to make the aforementioned and other objects, features and advantages of the present disclosure comprehensible, a preferred embodiment accompanied with figures is described in detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and, together with the description, serve to explain the principles of the disclosure.
[0030] FIGS. 1 to 4 are sectional views of fabrication process of a semiconductor device according to the one embodiment of the present disclosure.
[0031] FIGS. 5 to 7 are sectional views of fabrication process of a semiconductor device according to the another embodiment of the present disclosure.
[0032] FIGS. 8 to 11 are sectional views of fabrication process of a semiconductor device according to the another embodiment of the present disclosure.
[0033] FIGS. 12 is a sectional view of a semiconductor device according to the another embodiment of the present disclosure.
DESCRIPTION OF EMBODIMENTS
[0034] The present disclosure is described by the following specific embodiments. Those with ordinary skill in the arts can readily understand the other advantages and functions of the present disclosure after reading the disclosure of t his specification. The present disclosure can also be implemented with different embodiments. Various details described in this specification can be modified based on different viewpoints and applications without departing from the scope of the present disclosure.
[0035] As used herein, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Therefore, reference to, for example, a data sequence includes aspects having two or more such sequences, unless the context clearly indicates otherwise.
[0036] Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
[0037] FIGS. 1 to 4 are sectional views illustrating the manufacturing process of a semiconductor device according to some embodiments of the present disclosure. Referring to FIG. 1 , a substrate 110 having at least one transistor 120 is provided. The substrate 110 may be a silicon substrate with a plurality of bit line, and each bit line is electrically connected to the transistors 120 arranged in the same line, as the transistors 120 illustrated in FIG. 1 . However, the present disclosure is not limited thereto. In some embodiments of the present disclosure, the transistor 120 is a vertical silicon pillar 122 . For example, vertical silicon pillars 122 may be arranged periodically and respectively corresponding to different cells of a DRAM. As shown in FIG. 1 , in some embodiments of the present disclosure, the vertical silicon pillar 122 has a source electrode 124 at the top of the vertical silicon pillar 122 , a drain electrode 126 at the bottom of the vertical silicon pillar 122 , and a gate electrode 128 substantially at the middle of the vertical silicon pillar 122 . However, the present disclosure is not limited thereto. The relative positions of the source electrode 124 and the drain electrode 126 are exchangeable. In other embodiments of the present disclosure, the vertical silicon pillar 122 has the source electrode 124 at the bottom of the vertical silicon pillar 122 , accordingly, the drain electrode 126 at the top of the vertical silicon pillar 122 , and the gate electrode 128 substantially at the middle of the vertical silicon pillar. In general, the source electrode 124 and the drain electrode 126 may be formed in the vertical silicon pillar 122 by applying appropriate implant process to the vertical silicon pillar 122 . The gate electrode 128 comprises metal or doped semiconductor, and are positioned on both sides of the, vertical silicon pillar 122 . In FIG. 1 , the vertical silicon pillars 122 are vertical transistors 120 on the substrate 110 , each vertical silicon pillar 122 has the source electrode 124 and the drain electrode 126 to form a current channel which is perpendicular to the extending direction of the substrate 110 , and the gate electrode 128 to control the current flows or not. For example, in DRAM application, the gate electrodes 128 can be word lines which are crossed to the bit lines on the substrate 110 .
[0038] Referring to FIG. 1 , a first insulation layer 130 is formed to cover the transistor 120 . The first insulation 130 includes, for example, silicon oxide. In some embodiments of the present disclosure the first insulation 130 may be formed by chemical vapor deposition.
[0039] Referring to FIG. 2 , the first insulation layer 130 is patterned to form at least one opening 132 wherein a part of the transistor 120 is exposed by the opening 132 . The first insulation 130 may be patterned, for example, by litho-etching process to form the openings 132 . The part of the transistor 120 exposed by the opening 132 is the source electrode 124 and/or the drain electrode 126 of the transistor 130 . As illustrated in FIG. 2 , in some embodiments of the present disclosure, the source electrode 124 is at the top of the vertical silicon pillar 122 , and the source electrode 124 is exposed for the following epitaxy formation. In other embodiments of the present disclosure, the drain electrode 126 is at the top of the vertical silicon pillar 122 , and the drain electrode 126 is exposed for the following epitaxy formation.
[0040] Referring to FIG. 3 , an epitaxy 140 is formed in the opening 132 to cover the part of the transistor 130 . As illustrated in FIG. 3 , in some embodiments of the present disclosure, the source electrode 124 is exposed and the epitaxy 140 is formed on the source electrode 124 . In other embodiments of the present disclosure, the drain electrode 126 is exposed and the epitaxy 140 is formed on the source electrode 124 . The epitaxy 140 includes epitaxial silicon or other appropriate materials. The epitaxy 140 may be formed by selective CVD process to control the positions of the epitaxy 140 formed. For example, the growth of the epitaxy 140 only starts from the top of the silicon pillars 122 (the source electrode 124 or the drain electrode 126 ). It should be noticed that, since the epitaxy 140 is formed in the opening 132 , the growth of the epitaxy 140 is, confined by the opening 132 . It eliminates the risk that one epitaxy 140 contacts to another adjacent epitaxy 140 , therefore, the interference or short circuit of one transistor 120 and another adjacent transistor 120 is avoided. Besides, the shape of the epitaxy 140 is also confined by the opening 132 , therefore, the boundary of the epitaxy 140 is adjacent to sidewalls of the opening. Accordingly, the growth of the epitaxy 140 can be well controlled and the better uniformity between each epitaxy 140 on different transistors 120 can be achieved. In some embodiments of the present disclosure, the epitaxy 140 can be further implanted (as the arrows illustrated in FIG. 3 ) to form a lightly doped epitaxy to reduce the electrical field between junction and gate, thus the risk of current leakage can be reduced or eliminated. Further, the top surface of the epitaxy 140 may be substantially flat since the growth of the epitaxy 140 is confined by the opening 132 and the growth of the epitaxy 140 can be well controlled. It brings larger process margin for the following process, for example, cleaning and removing the native oxide formed on the epitaxy 140 before fulfilling with a conductive material.
[0041] Referring to FIG. 4 , in some embodiments of the present disclosure, the opening 132 can be fulfilling with a conductive material 150 . The conductive material 150 includes, for example, poly silicon, tungsten, titanium, titanium nitride, or a combination thereof. The conductive material 150 may be formed by, for example, chemical vapor deposition, sputtering or other appropriate thin-film processes. As illustrated in FIG. 4 , the conductive material 150 contacts to the epitaxy 140 , and the conductive material 150 is also electrically connected to the top of the silicon pillars 122 (the source electrode 124 or the drain electrode 126 ) via the epitaxy 140 . It should be noticed that the epitaxy 140 extends the channel length of the transistor 120 . To be more specific, the channel length of the transistor 120 starts from the top of the epitaxy 140 , which contacts with the conductive material 150 , to the bottom of the silicon pillars 122 . As aforementioned, when the dimension of the transistor is reduced, its channel length will also decrease with ease leading to problems such as short channel effect and decrease in turn-on current. The epitaxy 140 in the present disclosure can be the extension of the top of the silicon pillars 122 (as the source or the drain electrode), thus extends the channel length of the transistor 120 . Therefore, the issues such as short channel effect and decrease in turn-on current can be improved or eliminated. In addition, it can also reduce the electric field formed between the top of the silicon pillars 122 (as the source or the drain electrode) and the gate electrode 128 , so as the gate electrode 128 can be affected less and perform better controllability to the transistor 120 .
[0042] Referring to FIG. 5 , in other embodiments of the present disclosure, before forming the epitaxy 140 , a second insulating layer 160 is formed on the first insulation layer 160 , and the second insulation layer 160 is patterned to form the opening 132 , wherein the part of the transistor 120 is exposed by the opening 132 of the first and the second insulation layer. The second insulation 160 may also be composed of a single layer of material or stacked layers of different materials. The second insulation 160 includes, for example, silicon oxide, silicon nitride, or a combination thereof. In some embodiments of the present disclosure, the second insulation 160 may be formed by chemical vapor deposition. The second insulation 160 may be patterned, for example, by litho-etching process to form the openings 132 . The part of the transistor 20 exposed by the opening 132 is the source electrode 124 and/or the drain electrode 126 of the transistor 130 . The second insulating layer 160 can be a denser film than the first insulating film 130 . Therefore, the second insulating layer 160 provides better resistance in the following implanting or cleaning process, thus extends the process margin of these following processes. As illustrated in FIG. 6 and FIG. 7 , the epitaxy 140 is formed in the opening 132 to cover the part of the transistor 120 which is exposed by the opening 132 of the first insulation layer 130 and the second insulation layer 160 , and the conductive material 150 can also fulfill the opening 132 with a conductive material. The details of FIG. 6 and FIG. 7 are similar to aforementioned embodiments illustrated in FIG. 3 and FIG. 4 , and therefore are omitted here.
[0043] FIGS. 8 to 10 are sectional views illustrating the manufacturing process of a semiconductor device according to some other embodiments of the present disclosure. Referring to FIG. 8 , a substrate 210 having at least one transistor 220 is provided. The substrate 210 may be a silicon substrate with a plurality of bit line, and each bit line is electrically connected to the transistors 220 arranged in the same line, as the transistors 220 illustrated in FIG. 1 . The transistor 220 is a planar transistor which has a source electrode 224 , a drain electrode 226 and a gate electrode 228 which are substantially coplanar. In general, the source electrode 224 and the drain electrode 226 may be formed by applying appropriate implant process. The gate electrode 228 may comprises metal or doped semiconductor, and are positioned in the middle of the source electrode 224 and the drain electrode 226 . In FIG. 8 , the transistors 220 are planar transistors 220 on the substrate 210 , each transistor 220 has the source electrode 224 and the drain electrode 226 to form a current channel which is horizontal to the extending direction of the substrate 210 and the gate electrode 228 to control the current flows. Referring to FIG. 8 , a first insulation layer 230 is formed to cover the transistor 220 . The first insulation 230 includes, for example, silicon oxide. In some embodiments of the present disclosure, the first insulation 230 may be formed by chemical vapor deposition.
[0044] Referring to FIG. 9 , the first insulation layer 230 is patterned to form at least one opening 232 wherein a part of the transistor 220 is exposed by the opening 232 . The first insulation 230 may be patterned, for example, by litho-etching process to form the openings 232 . The part of the transistor 220 exposed by the opening 232 is the source electrode 224 and/or the drain electrode 226 of the transistor 230 . As illustrated in FIG. 9 , in some embodiments of the present disclosure, both of the source electrode 224 and the drain electrode 226 are exposed for the following epitaxy formation. In some other embodiments of the present disclosure, only one of the source electrode 224 or the drain electrode 226 is exposed for the following epitaxy formation.
[0045] Referring to FIG. 10 , an epitaxy 240 is formed in the opening 232 to cover the part of the transistor 230 . As illustrated in FIG. 10 , in some embodiments of the present disclosure, both of the source electrode 224 and the drain electrode 226 are exposed and the epitaxy 240 is formed on both of the source electrode 224 and the drain electrode 226 of the transistor 230 . The epitaxy 240 may be formed by selective CVD process to control the positions of the epitaxy 240 formed. It should be noticed that, since the epitaxy 240 is formed in the opening the growth of the epitaxy 240 is confined by the opening 132 . It eliminates the risk that one epitaxy 240 contacts to another adjacent epitaxy 240 , therefore, the interference or short circuit of one transistor 220 and another adjacent transistor 220 is avoided. Besides, the shape of the epitaxy 240 is also confined by the opening 232 , therefore, the boundary of the epitaxy 240 is adjacent to sidewalls of the opening. Accordingly, the growth of the epitaxy 240 can be well controlled and the better uniformity between each epitaxy 240 on different transistors 220 can be achieved. In some embodiments of the present disclosure, the epitaxy 240 can be further implanted (as the arrows illustrated in FIG. 10 ) to form a lightly doped epitaxy to reduce the electrical field between junction and gate, thus the risk of current leakage can be reduced or eliminated. Further, the top surface of the epitaxy 240 may be substantially flat since the growth of the epitaxy 240 is confined by the opening 232 and the growth of the epitaxy 240 can be controlled well. It brings larger process margin for the following process, for example, cleaning and removing the native oxide formed on the epitaxy 240 before fulfilling with a conductive material.
[0046] Referring to FIG. 11 , in some embodiments of the present disclosure, the opening 232 can be fulfilling with a conductive material 250 . The conductive material 250 includes, for example, poly silicon, tungsten, titanium, titanium nitride, or a combination thereof. The conductive material 250 may be formed by, for example, chemical vapor deposition, sputtering or other appropriate thin-film processes As illustrated in FIG. 11 , the conductive material 250 contacts to the epitaxy 240 , and the conductive material 250 is also electrically connected to both of the source electrode 224 and the drain electrode 226 of the transistor 220 via the epitaxy 240 . Referring to FIG. 12 , in some other embodiments of the present disclosure, the conductive material 250 contacts to the epitaxy 240 , and the conductive material 250 is only electrically connected to the source electrode 224 of the transistor 220 via the epitaxy 240 . However, the present disclosure is not limited thereto. In some other embodiments of the present disclosure, the conductive material 250 is only electrically connected to the source electrode 224 of the transistor 220 via the epitaxy 240 . It should be noticed that the epitaxy 240 extends the channel length of the transistor 220 . To be more specific, the channel length of the transistor 220 is the distance between the source electrode 224 and the drain electrode 226 which are contacted to the conductive material 250 . As aforementioned, when the dimension of the transistor is reduced, its channel length will also decrease with ease leading to problems such as short channel effect and decrease in turn-on current. The epitaxy 240 in the present disclosure can be considered as the extension of the source electrode 224 and the drain electrode 226 , thus the channel length of the transistor 220 is extended. Therefore, the issues such as short channel effect and decrease ire turn-on current can be proved or eliminated.
[0047] In summary, according to the present disclosure, the epitaxy is introduced on at least one of the gate electrode and the drain electrode of the transistor of the semiconductor device. Therefore, the channel length of the transistor can be extended so as to reduce the issues such as short channel while the dimension of the transistor is reduced. Further, since the growth of the epitaxy is confined by the openings which are respectively corresponding to one electrode (the source electrode or the drain electrode) of the transistor. The risk of short circuit by one epitaxy contacts to another adjacent epitaxy is eliminated. Therefore, the interference of one transistor and another adjacent transistor is avoided. Besides, since the shape of the epitaxy is confined by the opening, the growth of the epitaxy can be well controlled and the better uniformity between each epitaxy on different transistors can be achieved.
[0048] The present disclosure has been disclosed above in the preferred embodiments, but is not limited to those. It is known to persons skilled in the art that some modifications and innovations may be made without departing from the spirit and scope of the present disclosure. Therefore, the scope of the present disclosure should be defined by the following claims. | A semiconductor device includes a transistor disposed on a substrate, a first insulation layer, a second insulation layer, an epitaxy and a conductive material. The first insulation layer is disposed on the substrate and protruding over the transistor. The first insulation layer has a recess to expose a top portion of the transistor. The second insulation layer is disposed on the first insulation layer and conforms to the recess and exposes the top portion of the transistor. The epitaxy is disposed in the recess of the first insulation layer and overlaps the top portion of the transistor. The epitaxy conforms to sidewalls of the recess of the first insulation layer. The conductive material is disposed in the recess of the first insulation layer. The conductive material is electrically connected to the top portion of the transistor through the epitaxy, | 7 |
TECHNICAL FIELD
The present specification relates to cart assemblies and more specifically, interlocking primary and secondary cart assemblies with lock and release mechanisms.
BACKGROUND
It is often the case that relatively heavy machines or components of machines must be moved separately, but are then connected together to perform an operation. For example, a user may separately transport a tank and a welder machine when it is desirable to move the welder machine from point A to point B. Such separate moving of relatively heavy objects can provide ergonomics challenges. Accordingly, there exists a need for primary and secondary cart interlocking assemblies for transporting multiple components, where those components may have a use together.
SUMMARY
In one embodiment, an apparatus for an interlocking primary and secondary cart assembly may include a primary cart assembly including a primary support platform configured to support a primary working device thereon and wheels operatively connected to the primary support platform that movably support the primary support platform spaced from a floor and a secondary cart assembly including a secondary support platform configured to support a secondary working device thereon and wheel operatively connected to the secondary platform that moveably support the secondary support platform spaced from the floor. The assembly may further include a lock and release mechanism including a primary lock and release component connected to the primary cart assembly and a secondary lock and release component connected to the secondary cart assembly wherein the secondary lock and release component aligns with the primary lock and release component for locking therewith with the secondary cart assembly positioned on the primary support platform of the primary cart assembly.
In another embodiment, an interlocking primary and secondary cart assembly includes a primary cart assembly having a primary support platform configured to support a primary working device thereon and at least one wheel operatively connected to the primary support platform that movably support the primary support platform spaced from a floor, a secondary cart assembly comprising a secondary support platform configured to support a secondary working device thereon and at least one wheel operatively connected to the secondary platform that moveably support the secondary support platform spaced from the floor and a lock and release mechanism comprising a primary lock and release component connected to the primary cart assembly or the primary working device and a secondary lock and release component connected to the secondary cart assembly wherein the primary support platform of the primary cart assembly is configured to support and connect to the secondary cart assembly and the secondary working device, the secondary lock and release component aligns with the primary lock and release component for locking therewith with the secondary cart assembly positioned on the primary support platform of the primary cart assembly.
In another embodiment, a method of using an interlocking primary and secondary cart assembly including the steps of rotating a secondary cart assembly onto a primary support platform of the primary cart assembly, the primary cart assembly comprising a primary support platform configured to support a primary working device thereon and wheels operatively connected to the primary support platform that movably support the primary support platform spaced from a floor, the secondary cart assembly comprising a secondary support platform configured to support a secondary working device thereon and wheels operatively connected to the secondary platform that moveably support the secondary support platform spaced from the floor and securing the secondary cart assembly to the primary cart assembly using a lock and release mechanism thereby allowing for transportation of the interlocking primary and secondary cart assembly as a one piece assembly.
These and additional features provided by the embodiments described herein will be more fully understood in view of the following detailed description, in conjunction with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The embodiments set forth in the drawings are illustrative and exemplary in nature and not intended to limit the subject matter defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:
FIG. 1 illustrates a primary cart assembly and a secondary cart assembly in a disconnected configuration moving towards the primary cart assembly according to one or more embodiments shown and described herein;
FIG. 2 illustrates the primary cart assembly and the secondary cart assembly in an intermediate configuration positioned to rotate onto the primary cart assembly for interlocking therewith according to one or more embodiments shown and described herein;
FIG. 3 illustrates the primary cart assembly and the secondary cart assembly interlocked forming an interconnected primary and secondary cart assembly according to one or more embodiments shown and described herein;
FIG. 4 illustrates the interconnected primary and secondary cart assembly with the secondary cart assembly in a folded-in position according to one or more embodiments shown and described herein;
FIG. 5 illustrates a top view of the interlocked primary and secondary cart assembly before the secondary cart assembly is secured to the primary cart assembly according to one or more embodiments shown and described herein; and
FIG. 6 illustrates a top view of the interlocked primary and secondary cart assembly after securement of the secondary cart assembly to the primary cart assembly according to one or more embodiments shown and described herein.
DETAILED DESCRIPTION
Embodiments described herein relate to an interlocking primary cart assemblies and secondary cart assemblies to provide an interlocked primary and secondary cart assembly that can be transported as a single unit. The interlocked primary and secondary cart assembly includes a lock and release mechanism that can move between a locked configuration, locking the primary cart assembly and the secondary cart assembly, and a release configuration that allows separation of the primary cart assembly from the secondary cart assembly allowing for separate movement of the primary and secondary cart assemblies relative to one another.
The interlocking primary and secondary cart assemblies can provide an improved system for connecting and transporting a welder tank to a welder machine. The primary cart assembly, for example, can be configured to include the welder machine. Similarly, the secondary cart assembly can be configured to include the welder tank for use with the welder machine. The primary cart assembly can be configured to allow the secondary cart assembly to be rotated onto a platform of the primary cart assembly and then secured to the primary cart assembly allowing the entire interlocked primary and secondary cart assembly to be moved together as a one piece assembly during use.
Referring to FIG. 1 , an interlocking primary and secondary cart assembly 100 includes a primary cart assembly 102 and a secondary cart assembly 104 . In a general sense, the secondary cart assembly 104 is adapted to rest on and travels with the primary cart assembly 102 . The primary cart assembly 102 has a primary support platform 138 that is configured to hold the welding machine 106 or other working device in a generally permanent fixed position. The secondary cart assembly 104 is configured to hold a tank 108 or other working device which supplies fuel or otherwise interacts with the welding machine 106 .
The secondary cart assembly 104 includes a handle 110 and a support structure 112 including support beams 114 , 118 . The support beams 114 , 118 are connected by a pivot point 162 and include a locking mechanism 116 . The support beams 114 , 118 connect to a main cart portion 125 at pivot points 120 , 126 and allow the support structure 112 to fold in to a compressed configuration, such as illustrated in FIG. 4 . The secondary cart assembly 104 includes a plurality of wheels 122 , 124 allowing the user to more readily push the secondary cart assembly 104 from a first position to a second position. The wheels 122 , 124 also support a secondary support platform 130 at a location above the floor and allow pivoting of the secondary support platform 130 relative to the floor.
The secondary cart assembly 104 includes the secondary support platform 130 allowing the tank 108 to rest on the secondary support platform 130 . The tank 108 includes an upper end 154 and a lower end 152 . The lower end 152 is adapted to rest on an upper surface 127 of the secondary support platform 130 .
The secondary cart assembly 104 further includes a secondary lock and release mechanism 160 . The secondary lock and release mechanism 160 includes a latch 136 . The latch 136 is adapted to connect to a primary lock and release component 161 comprising a hook 148 provided on the welding machine 106 . Alternatively, the hook 148 may be connected directly to the primary car assembly 102 including the welding machine 106 .
The primary cart assembly 102 includes a lower support structure 163 comprising the primary support platform 138 and a side support structure 144 comprising a handle 146 . The support structure 138 is adapted to hold the welding machine 106 on the primary support platform 138 . The primary cart assembly 102 further includes the handle 146 and a plurality of wheels 140 , 142 . The plurality of wheels 140 , 142 support the primary support platform 138 at a location above the floor. The primary support platform 138 extends to an extended support structure 156 having an upper surface 134 . The extended support structure 156 extends forward, beyond the wheels 142 , and is arranged to engage with a lower surface 132 of the platform 130 of the secondary cart assembly 104 as will described in greater detail below.
FIGS. 1-4 illustrate the secondary cart assembly 104 rotating onto the primary cart assembly 102 and locking the secondary cart assembly 104 to a locked configuration. The directional arrow 150 , as illustrated in FIG. 1 , illustrates the secondary cart assembly 104 moving towards the primary cart assembly 102 . FIG. 2 illustrates an intermediate second position before rotation where the platform 130 begins to come into contact with the extended support structure 156 of the primary cart assembly 102 . In this example, the secondary support platform 130 is rotated to an elevation at least partially above the extended support structure 156 and is used as a lever to raise the tank 108 onto the primary support platform 138 .
FIG. 3 illustrates the secondary cart assembly 104 rotating onto the primary support platform 156 of the primary cart assembly 102 . After the secondary cart assembly 104 is rotated up and onto the primary cart assembly 102 , the secondary cart assembly 104 can be locked to the primary cart assembly 102 . As can be seen, the lock and release mechanism 165 includes the primary lock and release component 161 and secondary lock and release mechanism 160 that align the secondary cart assembly 104 on the support platform 138 of the primary cart assembly 102 . Once the secondary cart assembly 104 is locked to the welding machine 106 , the support structure 112 of the secondary cart assembly 104 may be moved to a compressed configuration, such as illustrated in FIG. 4 .
The lock and release mechanism 165 is illustrated in further detail in FIGS. 5 and 6 . FIG. 5 illustrates the lock and release mechanism 165 before the latch 136 has been engaged. FIGS. 5 and 6 illustrate the secondary cart assembly 104 holding the tank 108 after the secondary cart assembly 104 has been rotated onto the primary support platform 138 of the primary cart assembly 102 . The primary support platform 138 has a sufficient surface area to accept the platform 130 . Specifically, primary support platform 138 may have at least 3 times the length of the platform 130 . Further, when rotating the platform 130 onto the primary support platform 138 , there can be an at least ⅓ overlap of the second support platform 130 over the extended support structure 156 (such as shown in FIG. 2 ) to allow the user to gain sufficient rotation and leverage.
The secondary cart assembly 104 can include a cradle structure 105 configured to hold the tank 108 . The secondary cart assembly 104 includes the secondary lock and release component 160 . The secondary lock and release component 160 includes a handle 170 pivotally connected to the latch 176 . The latch 176 is connected to the handle 170 at a pivot point 174 . The latch 176 includes an aperture 178 arranged to connect with the hook 184 of the welding machine 106 . The latching mechanism 160 is connected to the secondary cart assembly 104 by means of a connector portion 180 . The primary cart assembly 102 (or the welding machine 106 ) includes the primary lock and release component 161 including the hook 184 having a hook portion 186 . The hook portion 186 is arranged to connect with the aperture 176 of the latch 174 .
In an unlocked configuration, as illustrated in FIG. 5 , the lock and release mechanism 165 is illustrated before securement. FIG. 6 illustrates the lock and release mechanism 165 in a secured and locked position where the latch 176 is provided over and connected to the hook 184 . In some embodiments, the hook 184 may be connected directly to the primary cart assembly 102 rather than connected directly to the welding machine 106 .
The secondary lock and release component 160 can be provided approximately midway up the secondary cart assembly 104 . The latching mechanism 160 can be provided at this location to be convenient to the user allowing the user to easily lock and secure the latching mechanism 160 . Further, the secondary lock and release component 160 can be provided at the upper end of the welding machine 106 to raise the center of gravity and provide a more secure connection of the tank cart to the primary cart assembly 102 .
Accordingly, provided herein is an improved cart assembly for moving relatively heavy objects. Specifically, the present specification provides for a primary and secondary cart interlocking assemblies for transporting multiple components, where those components may have a use together, such as a welding machine and a corresponding tank. The primary and secondary cart interlocking assemblies allow for simultaneous movement of the primary cart assembly and the secondary cart assembly as a single assembly thereby wielding improved ergonomics to the user.
It is noted that the terms “substantially” and “about” may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.
While particular embodiments have been illustrated and described herein, it should be understood that various other changes and modifications may be made without departing from the spirit and scope of the claimed subject matter. Moreover, although various aspects of the claimed subject matter have been described herein, such aspects need not be utilized in combination. It is therefore intended that the appended claims cover all such changes and modifications that are within the scope of the claimed subject matter. | An interlocking primary and secondary cart assembly may include a primary cart assembly including a primary support platform configured to support a primary working device and wheels operatively connected to the primary support platform that movably support the primary support platform spaced from a floor and a secondary cart assembly including a secondary support platform configured to support a secondary working device and wheel connected to the secondary platform that moveably support the secondary support platform spaced from the floor. The assembly may further include a lock and release mechanism including a primary lock and release component connected to the primary cart assembly and a secondary lock and release component connected to the secondary cart assembly wherein the secondary lock and release component aligns with the primary lock and release component for locking therewith with the secondary cart assembly positioned on the primary support platform of the primary cart assembly. | 1 |
This application claims priority to U.S. Provisional Patent Application No. 60/492,035, entitled, “D ECOUPLED V ACUUM P ACKAGING M ACHINE ” by Landen Higer and Alexandre A. N. Baptista, filed on Jul. 31, 2003, and which is hereby incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention generally relates to vacuum packaging machines. More particularly, the invention is directed to appliance configurations that provide ease of use and convenient storage.
BACKGROUND
Vacuum packaging is a process for removing oxygen and other gases from food and other items that deteriorate in the presence gases. For example, food spoilage can occur due to oxidation and valuable manuscripts deteriorate when exposed to air. Metal objects can corrode or tarnish when exposed to moist air. Thus, food and other items can be vacuum packaged in a storage bag or storage container in order to increase either their “shelf life” or useful life. However, such appliances can be unwieldy and occupy too much counter space and/or storage space. Thus, there is a need for vacuum packaging appliances that are configured for both ease of use and convenient storage.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example, and not by way of limitation.
FIG. 1A is an isometric view that illustrates one embodiment of a vacuum packaging appliance with detachable wand;
FIG. 1B is a transverse cross-sectional view through the detachable wand, taken in the direction of arrows A—A in FIG. 1A ; and
FIG. 1C is an isometric view that illustrates a storage configuration of a vacuum packaging appliance with detachable wand with storage canister.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
An appliance for vacuum packaging storage bags and/or storage canisters 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 unnecessarily obscuring the present invention.
FIG. 1A is an isometric view that illustrates certain embodiments of a vacuum packaging appliance with a wand. In FIG. 1A , the configuration of the vacuum packaging appliance 103 is one that allows for a small footprint. Base 102 includes a control panel 106 and a storage slot 152 for wand 104 . Wand 104 is a separate unit that is decoupled from base 102 . Wand 104 is also referred to herein as a receptacle unit.
Wand 104 includes a compartment 117 with a lid 114 . Compartment 117 includes a vacuum chamber. The vacuum chamber includes a vacuum channel that is in communication with the vacuum pump in base 102 through vacuum hose/seal conductor 158 . Further, the vacuum chamber includes one or more gaskets for statically sealing the vacuum chamber when the lid 114 is in the closed position. For example, there may be a gasket on compartment 117 surrounding the vacuum channel and/or a corresponding gasket on lid 114 . Compartment 117 may optionally include a storage bag-cutter (not shown) integrated into lid or base, and a shelf mechanism for holding one or more rolls of storage bags. Further, wand 104 may include locks 105 that automatically lock during the sealing and/or vacuuming operation. Locks 105 are released in order to pop lid 114 open. Wand 104 also includes a vacuum-release mechanism for contacting the vacuum chamber with ambient atmosphere.
Base 102 includes a vacuum pump (not shown), sealing mechanism (not shown) and controls (not shown) associated with the operation of the vacuum pump and sealing mechanism.
According to certain embodiments, base 102 has a control panel 106 at the top frontal portion of the base. Control panel 106 includes an instant seal button 110 to manually start sealing a storage bag, and a vacuum button 112 to start removing gases from storage bags or canisters.
To explain, the sealing function may be automatically activated when the lid of wand 104 is in the closed position over one end of a storage bag, which end is not in a vacuum channel of the vacuum packaging appliance. When a storage bag is being evacuated through activation of the vacuuming function, the instant seal button may be used to seal a storage bag before a complete vacuum is created in the storage bag. This feature is useful when vacuum packaging fragile items so that such items do not get crushed. The sealing mechanism in base 102 activates a heating element in wand 104 through a seal conductor that is ganged with a vacuum hose, such as vacuum hose/seal conductor 158 . The heating element may be in the form of a heating strip.
In addition, control panel 106 may include indicator lights to signal the start or completion of various processes such as the sealing process, vacuum process and/or machine re-programming when transitioning from one process to the next. Control panel 106 may optionally include an automatic On/Off button. The automatic On/Off button acts as a fail-safe mechanism to ensure that the heat sealing and/or vacuum mechanisms are not unintentionally activated. Further, control panel 106 may optionally include a Cancel Button for canceling a given operation that is in progress.
Control panel 106 may also include a sealing time adjustment knob for controlling the heating element associated with the heat sealing mechanism. For example, the sealing time adjustment can be set to a first setting when storage bags are being sealed. The heat-sealing time adjustment can be set to a second setting when canisters are being sealed. In the case of sealing canisters, there is no need for activating the heating element.
In certain embodiments, the vacuum operation for removing gases automatically starts when the lid of wand 104 is in the closed position. In such cases, control panel 106 may include an Extended Vacuum Button. The Extended Vacuum Button may be used to extend the vacuum time to ensure that the maximum amount of air is removed, especially when using extra large storage canisters or bags.
FIG. 1B is a transverse cross-sectional view through the wand 104 , taken in the direction of arrows A—A in FIG. 1A . FIG. 1C is an isometric view that illustrates a storage configuration of a vacuum packaging apparatus 103 with wand 104 and with storage canister 160 . As shown in FIG. 1C , wand 104 may be conveniently stored in storage slot 152 . The gases in storage canister 160 can be evacuated using vacuum hose 158 to connect storage canister 160 to a vacuum pump in base 102 .
Storage bags and canisters may be used with the vacuum packaging appliance described above. Storage bags and rolls may be made from special 3-layer plastic material with channels that facilitate the removal of gases during the vacuum operation. The storage bags and rolls are reusable, washable and recyclable.
Storage canisters include a specially designed lid with a port for connecting to the vacuum pump of the vacuum packaging appliance through a hose attachment. The canister lids are designed to seal the canister once the gases are removed from the canister. The storage bags and canisters may be used to store food or other items for which vacuum packaging is desired.
A specially designed jar sealer may be used for vacuum packaging standard-mouth mason jars. The jar sealer is designed to fit mason jars and can be connected to the vacuum pump of the vacuum packaging appliance through a hose attachment. Similarly, bottle stoppers may be used to vacuum package bottles to extend the life of liquids. The stoppers are designed for connection to the vacuum pump of the vacuum packaging appliance through a hose attachment.
In the foregoing specification, embodiments of the invention have been described with reference to numerous specific details that may vary from implementation to implementation. Thus, the sole and exclusive indicator of what is the invention, and is intended by the applicants to be the invention, is the set of claims that issue from this application, in the specific form in which such claims issue, including any subsequent correction. Any express definitions set forth herein for terms contained in such claims shall govern the meaning of such terms as used in the claims. Hence, no limitation, element, property, feature, advantage or attribute that is not expressly recited in a claim should limit the scope of such claim in any way. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. | The foot-print of a vacuum packaging appliance may be decreased by decoupling the appliance into a base component and a movable receptacle unit according to certain embodiments of the invention. | 1 |
CROSS-REFERENCES TO RELATED APPLICATIONS
This application claims priority to and is a continuation-in-part of International Patent Application No. PCT/EP2009/006690, filed Sep. 16, 2009, which claims priority to German Patent Application No. DE 10 2008 047 400.2, filed Sep. 16, 2008, the disclosures of which are hereby incorporated by reference in their entirety.
BACKGROUND OF THE INVENTION
The present invention relates to a measuring system for ophthalmic surgery having a wavefront sensor and imaging optics. In particular, the invention relates to a measuring system for ophthalmic surgery having a wavefront sensor and imaging optics and which is suitable for use in surgery, in particular for use in eye surgery, by providing a sufficiently large distance between the imaging optics and the object under inspection. Furthermore, the invention relates to a measuring system for ophthalmic surgery having a wavefront sensor and an OCT system.
Wavefront sensors, which are configured to characterize the form of a wavefront of measuring light, are known in the art. Such wavefront sensors may in particular be used to measure aberrations of a human eye by using a Hartmann-Shack sensor, as described in the article of J. Liang, B. Grimm, S. Goelz, J. F. Bille, “Objective measurement of a Hartmann-Shack wavefront sensor”, J. Opt. Soc. Am. A 11 (1994) pp. 1949-1957. In such a system, the Hartmann-Shack sensor comprises in particular an array of microlenses which is arranged in a plane, wherein in a common focal plane of the microlenses, a position-sensitive light sensor is arranged. With such a Hartmann-Shack sensor, a form of a wavefront, which is incident onto the array of microlenses may be determined by measuring local inclinations of a wavefront in regions corresponding to each of the microlenses.
For measuring the optical properties of a human eye, an illumination spot, which is as small as possible, is generated on the retina of the human eye. A nearly spherical wave emanates from this point-like illumination spot, traverses the vitreous body, the lens and the cornea and leaves the human eye. The form of the wavefront is altered when it traverses the different optical interfaces of the human eye. This results in a deviation of the exiting wavefront from a plane wavefront. These deviations from a plane wavefront may be represented by local inclinations within a lateral region and thereby may be measured by using a Hartmann-Shack wavefront sensor.
Document US 2005/0241653 A1 discloses a wavefront sensor which can be arranged and mounted between an objective lens of a microscope system and an object under inspection.
Document U.S. Pat. No. 6,550,917 B1 discloses a wavefront sensor, which is designed such that a spherical wavefront is transformable into a plane wavefront. The spherical wavefront may for example be a wavefront, which exits an ametropic eye having a spherical aberration. Thereby, it is possible to increase a measuring range of the wavefront sensor.
The document DE 103 60 570 B4 discloses an optical measuring system, which comprises an OCT-system and a wavefront analysis system. Based on a measurement of a form of a wavefront, an adaptive optical element is controlled such that wavefronts, which are measured by a wavefront detector are substantially plane wavefronts. Thereby, it is possible to obtain an improved OCT signal.
However, the wavefront sensors, which are disclosed in the documents mentioned above are only of limited use in surgical operations, since they require a short distance between the object and the optical component which is located closest to the object.
Therefore, it is an object to provide an optical measurement system having a wavefront sensor and which is suitable for use in surgical operations. In particular, it is an object to provide a measuring system having a wavefront sensor and which is suitable for use in eye surgery, in particular cataract surgery.
It is a further object to provide an optical measuring system having a wavefront sensor and an OCT system and which allows to inspect an object by analyzing wavefronts, which emanate from the object, wherein the analysis is performed by measuring a three-dimensional structure data set. The measuring system further has to be suitable for surgical operations.
SUMMARY OF THE INVENTION
The present invention has been accomplished taking the above problems into consideration.
Embodiments provide an optical measuring system, or a measuring system for eye surgery, which provides the surgeon with sufficient working space to perform surgical operations.
According to an embodiment, there is provided an optical measuring system, which comprises a wavefront sensor for characterizing a form of a wavefront of measuring light in an entry region of the wavefront sensor; and imaging optics having a first optical assembly and a second optical assembly for imaging an object region onto the entry region of the wavefront sensor by using the measuring light, wherein the following relation holds:
1.1 *f≦d , wherein
f denotes a focal distance of the first optical assembly; and d denotes a distance between the object region and the first optical assembly.
The wavefront sensor may comprise an extensive array of refractive or diffractive optical elements. The array of optical elements may be an array of microlenses. Each of these refractive or diffractive optical elements may be designed such that the measuring light is focused in a focal plane. In a common focal plane, which is formed from the individual focal planes of the refractive or diffractive optical elements, there may be provided a position-sensitive light sensor. The position-sensitive light sensor may for example be a CCD camera and/or a CMOS sensor or any other light sensitive sensor. The position-sensitive light sensor may be configured to resolve a spatial intensity distribution. The position-sensitive light detector may be arranged in a plane, which is oriented perpendicular to an optical axis of the wavefront sensor. The entry region of the wavefront sensor may be defined by a region, in which the array of refractive or diffractive optical elements is arranged. This region may have the form of a plane. This plane may for example be defined by fitting a plane to optical interfaces of the refractive or diffractive optical elements, wherein the optical interfaces comprise those optical surfaces of the wavefront sensor, which are located furthest away from the position-sensitive light sensor.
Depending on a form of a wavefront of measuring light, which is incident on the wavefront sensor, light ray bundles of this wavefront are imaged onto a corresponding array of regions on the position sensitive light detector by the array of refractive or diffractive optical elements. These regions of the focused light ray bundles may have the form of an ellipse or a circle. An average position or a position of a center of mass of each of the regions relative to a lateral position of the corresponding refractive or diffractive optical elements is indicative of a local inclination or tilt of the light ray bundle of the respective refractive or diffractive optical element, wherein the wavefront, which is incident on the wavefront sensor comprises this light ray bundle.
The position-sensitive light sensor may comprise a plurality of sensor segments or pixels. Depending on a light intensity, which is incident on each of the detector segments, electrical signals are generated by the wavefront sensor. Then, these electrical signals are transmitted to a processing unit. The processing unit is configured to determine from the electrical signals a position of the focused light ray bundles. The position may be a position of the center or center of mass, for example as a center of mass of a region, which extends over several detector segments and which is formed by an incident focused bundle of light rays, which has traversed one of the refractive or diffractive optical elements of the wavefront sensor.
According to embodiments, the wavefront sensor is a Hartmann-Shack sensor. Alternatively, the wavefront sensor may for example be an interferometer, a classic Hartmann-Test, a Ronchi test, Talbot interferometry, or a phase retrieval method. Furthermore, the optical measuring system may be configured such that a possible astigmatic aberration of the eye of the patient is pre-compensated by a variable cylindrical lens. The cylindrical lens may be rotatably supported. For example, the cylindrical lens may be a liquid lens.
The optical measuring system may further comprise a light source for illuminating an object under inspection. The measuring system may be configured to illuminate a region of the retina of the eye under inspection, wherein the region is as small as possible. A wavefront of measuring light, which is substantially parallel or spherical may be incident on the eye under inspection, and after the wavefront has traversed the cornea, the lens and the vitreous body of the eye under inspection, the wavefront is incident on the retina as a substantially spherical wavefront. Thereby, a region of the retina is illuminated, which has a small extent. Depending on an ametropia of the eye under inspection, this region may have the form of a circle or an ellipse. The difference between the length of the major axes of the ellipse may increase with the astigmatic aberration of the eye under inspection.
In order to measure the form of a wavefront which is emanating from an eye under inspection, the wavefront is directed onto the entry region of the wavefront sensor. For this purpose, the optical measuring system comprises imaging optics having a first optical assembly and a second optical assembly. The optical assemblies may comprise one or a combination of the following: refractive optical elements, diffractive optical elements, such as mirrors and/or lenses and/or gratings, and/or one or more electronically or mechanically controllable variable lenses or mirrors, which may be designed such that their optical refractive power is adaptable by varying their shape. Optical components of an optical assembly may have a fixed position relative to each other, such as cemented elements, or alternatively, individual lenses and/or cemented elements, which are mounted using lens mounts.
By traversing the first optical assembly, light, which emanates from a point in the focal region of the first optical assembly into different directions is transformed into a bundle of light, which is consists of substantially parallel light rays. By this fact, a position of the focal region of the first optical assembly is determinable. The focal region may have the form of a plane, which is located perpendicular to an optical axis of the first optical assembly. In this case, the focal region may be referred to as the focal plane. The focal point of the first optical assembly may be defined as the point, where the optical axis of the first optical assembly intersects the focal plane. An incident ray of light, which passes through the focal point of the first optical assembly and which forms a small angle with the optical axis, is transformed by the first optical assembly into an outgoing light beam, which runs parallel to the optical axis of the first optical assembly. A point of intersection of the extended outgoing light beam with the extended incident light beam is located in the principal plane of the first optical assembly. The focal length f of the first optical assembly is defined by the distance between the principal plane of the first optical assembly and the focal plane of the first optical assembly.
The distance d between the object region and the first optical assembly is defined by a distance between the object region and an optical surface of a component of the first optical assembly, wherein this optical surface may represent an optical surface of components of the first optical assembly, which is located closest to the object region along a beam path of the measuring light. This component of the first optical assembly is an optical component having the effect of a lens, i.e. a component which has a refractive power of greater than zero. For example, this component is not a plane-parallel plate or any other form of a component which does not modify a form of a wavefront of measuring light. Hence, further optical components may be arranged in the beam path of measuring light between the object region and the first optical assembly at a distance from the object region, which is smaller than d. These further optical components may have a refractive power of zero or a refractive power which is small compared to the refractive power of the first optical component, such as smaller than 5% or smaller than 1% of the refractive power of the first optical assembly. The refractive power of the first optical assembly is given by the reciprocal of the focal length, i.e. by 1/f.
The distance d thereby represents a free space between the first optical assembly and the object under inspection. This free space is sometimes referred to as working space and the distance d is sometimes referred to as working distance. By fulfilling the condition 1.1*f≦d, it is ensured that the working distance d is greater than the focal length f of the first optical assembly. An increase in d thereby leads to an increase of the working distance, which ma be advantageous in surgical operations such as in surgical operations performed on the human eye.
Moreover, the range of focal lengths of the first optical assembly is limited by various constraints. One of such constraints is the magnification, which is necessary to image a region having the diameter of the pupil of the eye onto the entry region of the wavefront sensor. A further constraint is a total length of the imaging optics, which typically should be designed compact in size. Therefore, it is typically not possible to increase the focal length of the first optical assembly until a sufficient working distance is achieved. Consequently, it is advantageous to have an measuring system for ophthalmic surgery, which fulfills the condition 1.1*f≦d.
According to an embodiment, 1.5*f≦d holds, or 1.75*f≦d holds, or 2*f≦d holds. For particular applications, it is advantageous, to provide a comparatively small focal length of the first optical assembly. Also in this case, a sufficiently large working distance can be attained for conducting surgical operations.
According to an embodiment, d≧150 millimeters holds, or d≧175 millimeters holds, or d≧190 millimeters holds. Such working distances allow to conduct surgical operations under a variety of requirements, such as requirements, which result from conducting eye surgery. According to further embodiments, d≦500 millimeters holds, or d≦300 millimeters holds, or d≦200 millimeters holds.
According to an embodiment, at least one of the first optical assembly and the second optical assembly is a refractive optical assembly, such as for example a lens assembly. A lens assembly is a set of lenses, which comprises one or more lenses. A lens assembly may consist of cemented elements. Lenses of a lens assembly may be arranged at a fixed position relative to each other.
According to an embodiment, the optical measuring system further comprises a third optical assembly, which is arranged and configured to image the object region along a beam path of the microscope onto an image region, which is different from the entry region of the wavefront sensor. The image region may be located at a distance from the entry region of the wavefront sensor. Thereby, it is possible to perform optical microscopy of the object region in addition to performing an analysis of the wavefront. Performing optical microscopy may be helpful during conducting surgical operations.
According to an embodiment, the object region is located at a focal region of the first optical assembly.
According to an embodiment, the first optical assembly comprises a first optical subassembly and a second optical subassembly, which are located at a distance from each other. The first optical assembly consists of the first optical subassembly and the second optical subassembly. By way of example, the first optical subassembly and the second optical subassembly are arranged at a fixed position relative to each other.
According to an embodiment, an optical path, which is traversed by the measuring light along the beam path of the measuring light between the first optical assembly and the second optical assembly, is adaptable. The adaptability of the optical path has the advantage that a spherical aberration of a human eye under inspection is pre-compensatable. Thereby, it is possible to minimize a curvature of the wavefront, which is incident on the wavefront sensor and thereby to increase a measuring range or a dynamic range of the wavefront sensor. In case the wavefront of measuring light has a spherical form when being incident on the first optical assembly, the wavefronts in the entry region of the wavefront sensor may be transformed into wavefronts having a substantially plane form. This transformation may be adapted by increasing or decreasing the optical path between the first optical assembly and the second optical assembly, by increasing or decreasing the optical path between the second optical subassembly of the first optical assembly and the second optical assembly.
Even when varying the optical path between the first optical assembly and the second optical assembly, the focal region of the first optical assembly which may consist of the first optical subassembly and the second optical subassembly, is still imaged onto the entry region of the wavefront sensor. The varying of the optical path may comprise moving/displacing the second optical subassembly relative to the second optical assembly. In other words, the second optical subassembly may be configured such that it is displaceable or movable relative to the second optical assembly. There may be provided an actuator for varying the optical path, wherein the actuator is designed to provide a driving force for displacing or moving the second optical subassembly relative to the second optical assembly. The actuator may be a motor or an actuator, which may be configured to transmit a driving force for the displacement, such as an actuation mechanism like a screw. The displacement may be performed along a track or guide. An amount of the displacement, such as a distance of the displacement, may be detected and measured by a detector. The actuator may be in signal communication with a controller, such that the controller may activate the actuator. The controller may comprise or make use of a calibration curve, which allows to convert between the amount of a spherical aberration of the eye under inspection and a distance of a displacement for pre-compensating this ametropia. By using the calibration curve, it is possible to control the actuator for displacing the second optical subassembly relative to the second optical assembly based on a known ametropia of the eye under inspection.
According to an embodiment, the measuring system for ophthalmic surgery is configured to characterize a form of a wavefront of measuring light, which emanates from an eye, which is arranged in an object region, wherein the eye has a spherical aberration of between −5 dpt (diopters) to +25 dpt (diopters), by varying the optical path between the first optical assembly and the second optical assembly. The sign of the spherical aberration of the eye is defined such that an aphakic eye, i.e. an eye with the natural lens removed, has a spherical aberration of about +20 dpt.
According to an embodiment, the optical measuring system further comprises a reflector for deflecting the measuring light, for example by 180°, wherein the reflector is displaceably arranged between the first optical assembly and the second optical assembly in the beam path of the measuring light for varying the optical path traversed by the measuring light. By way of example, the reflector is displaceably arranged between the second optical subassembly of the first optical assembly and the second optical assembly in the beam path of the measuring light.
According to an embodiment, the reflector comprises at least two mirror surfaces, which are arranged at an angle different from zero. In other words, the two mirror surfaces are arranged at an angle relative to each other, which is different from zero. The reflector may for example comprise two or three mirrors, wherein the reflector does not comprise any further reflecting surfaces. It is advantageous to use exactly two mirrors due to the favourable polarization behavior.
According to an embodiment, the optical measuring system further comprises a retroreflector, which is arranged between the first optical assembly (for example the second optical subassembly of the first optical assembly) and the second optical assembly in the beam path of the measuring light. A retroreflector is an optical system, which substantially reverses a propagation direction of the measuring light. This feature is substantially independent from an orientation of a propagation direction of the measuring light relative to the retroreflector. By way of example, the measuring light is not reflected by the retroreflector along the beam path of the incident measuring light, but along a path, which is laterally displaced relative to the beam path of the incident measuring light. In other words, the reflected path of measuring light, which is outgoing from the retroreflector is parallel to and located at a distance from the path of measuring light which is incoming onto the retroreflector. By arranging a retroreflector between the second optical subassembly and the second optical assembly, it is possible to vary the optical path between the second optical subassembly and the second optical assembly by displacing the retroreflector. A displacement of the retroreflector in a direction parallel to the optical axis of the first optical assembly by a distance 1 results in an increase or decrease of the optical path between the second optical subassembly and the second optical assembly by 2*n*1, wherein n denotes a refractive index of a medium within the beam path of the measuring light between the second optical subassembly and the second optical assembly. Providing the retroreflector allows to design the optical measuring system very compact in size. This in turn allows the optical measuring system to be mounted within or beneath a microscope system.
According to an embodiment, the retroreflector comprises a corner cube. A corner cube comprises a transparent body, which substantially has a form of a three-sided pyramid. The three-sided pyramid may comprise three triangles which are oriented perpendicular to each other, each of which being in the form of an isosceles, right-angled triangle, and further a surface in the form of an equilateral triangle. With this corner cube, an incident light beam is reflected by the corner cube at three surfaces. The mirroring process may result from total internal reflection. However, it is also conceivable, that a reflective coating is applied to the surfaces at which a mirroring process occurs, for example by applying a metallic coating. Thereby, a possible polarization of the light is influenced in a different way.
According to an embodiment, the optical measuring system further comprises a beam splitter, which is arranged between the entry region of the wavefront sensor and the second optical assembly. The beam splitter may be designed as a polarization beam splitter. The beam splitter may advantageously be used for coupling measuring light into the beam path. Hence, the measuring light on the way from the beam splitter to the object in the focal region of the first optical assembly traverses substantially the same path as the light, which emanates from the object on the way to the beam splitter. On the way from the beam splitter to the object, the measuring light traverses the second optical assembly and the first optical assembly (for example the first optical subassembly and the second optical subassembly of the first optical assembly). On the way from the object to the beam splitter, the measuring light traverses the first optical assembly (for example the first optical subassembly and the second optical subassembly of the first optical assembly) and the second optical assembly. Furthermore, the measuring light reaches the wavefront sensor along a portion of the beam path, which is not traversed by the measuring light on the way from the beam splitter to the object. Thereby, it is for example ensured, that in the case of an eye under inspection, which has a spherical aberration, the measuring light, which illuminates the eye, is adaptable with respect of a curvature of the wavefront of the measuring light, such that the illumination spot on the retina of the eye under inspection is as small as possible. This may be performed by varying the optical path between the second optical assembly and the second optical subassembly.
According to an embodiment, the following relation holds: d(1,2)≧f1*d/(d−f1), wherein d(1,2) represents a distance between components of the first optical subassembly and components of the second optical subassembly and f1 represents a focal length of the first optical subassembly. The first optical subassembly and the second optical subassembly are located for example along the optical axis of the first optical assembly at a distance from each other, such that light beams, which emanate from a point in the focal region of the first optical assembly, intersect between the first optical subassembly and the second optical subassembly after having traversed the first optical subassembly. In a region of such an intersection, an intermediate image of the object region which is arranged in the focal region of the first optical assembly may be formed. d(1,2) represents a distance along an optical axis of the first optical assembly between an optical surface of a component of the first optical subassembly and an optical surface of a component of the second optical subassembly, wherein both components have an optical power different from zero and wherein both optical components are those optical components of the first and second optical subassembly, respectively, which have the smallest distance from each other.
According to an embodiment, the first optical subassembly comprises a fist lens group, which may comprise or consist of an objective lens; and he first optical subassembly further comprises a second lens group, which is arranged at a distance from the first lens group, wherein the microscope beam path traverses the first lens group of the first optical subassembly and wherein the third optical assembly comprises a zoom system. Thereby, the beam path of the measuring light for the wavefront sensor as well as the microscope beam path traverses the first lens group of the first optical subassembly. Thereby, it is possible to provide an optical measuring system, which allows to perform an analysis of the wavefront and at the same time optical microscopy, wherein the first lens group of the first optical subassembly is used for both purposes. Thereby, it is possible, to provide an integration of the components of the optical measuring system, which is compact in size.
According to an embodiment, a mirror surface, such as a mirror surface of a folding mirror is arranged in the beam path of the measuring light between the first lens group and the second lens group of the first optical subassembly. The mirror surface is provided for spatially separating the beam path of the measuring light from the microscopy beam path.
According to an embodiment, the second lens group of the first optical subassembly and the second optical subassembly form an afocal system. The measuring system may comprise an afocal system, which consists of the second lens group of the first optical subassembly and the second optical subassembly. The afocal system may be a Kepler telescope. By traversing an afocal system, light, which consists of plane wavefronts is transformed into light which also consists of plane wavefronts. A Kepler telescope is an optical system which consists of two lenses or lens systems. The two lenses or lens systems are arranged at a distance from each other along the optical axis, wherein the distance may correspond to the sum of the focal lengths of both lenses or lens systems.
According to an embodiment, the object region is located in a focal region of the first lens group of the first optical subassembly. The first lens group of the first optical subassembly may be referred to as a main objective lens of a microscopy system. Hence, the object region is located in the focal region of the main objective lens of the microscopy system. This is advantageous in case further optical components are used downstream of the main objective lens, such as a zoom system or an eye-piece.
According to an embodiment, the third optical assembly comprises an objective lens and a zoom system, wherein the beam path of the measuring light is free from traversals of the objective lens and wherein a mirror surface is arranged in the beam path of the measuring light between the object region and the first optical subassembly. In other words, the beam path of the measuring light does not traverse the objective lens. According to this embodiment, none of the components of the optical measuring system, mentioned so far, are provided for an analysis of the wavefront and for conducting optical microscopy. This may have the advantage that the components for an analysis of the wavefront may be designed such that they are detachably mountable on an optical microscopy system and hence may be dismounted for performing an analysis of the wavefront. Furthermore, the components may be designed such that they are mountable on different optical microscopy systems without requiring significant optical components of the optical microscopy system or without having to adapt significant optical components of the optical microscopy system.
According to an embodiment, the object region is located in a focal region of the objective lens.
According to an embodiment, the object region is different from a focal region of the first optical assembly. The object region may be located at a distance from the focal region of the first optical assembly.
According to an embodiment, the first optical assembly and the second optical assembly together form an afocal system, such as for example a Kepler telescope. The measuring system comprises an afocal system, which consists of the first optical assembly and the second optical assembly.
According to an embodiment, a beam splitter is displaceably arranged between the first optical assembly and the second optical assembly in the beam path of the measuring light. Through the beam splitter, illumination light is directable to the object region. For example, the measuring system may comprise an actuator, which is attached to the beam splitter, and which is configured to displace the beam splitter upon receiving control signals from a control unit of the measuring system.
According to an embodiment, a mirror surface is arranged between the first optical assembly and the object region. Thereby, the optical measuring system is combinable with a microscopy system, wherein the beam splitter decouples from the light, which is used for microscopy a portion, which forms the measuring light for wavefront analysis.
According to an embodiment, the measuring system for ophthalmic surgery further comprises an OCT system having an OCT light source for generating an OCT measuring light, wherein in a beam path of the OCT measuring light between the first optical assembly and the second optical assembly or between the second optical assembly and the entry region of the wavefront sensor, there is arranged an OCT beam splitter such that OCT measuring light is directed to at least the first optical assembly for illuminating the object region. In case the OCT beam splitter is arranged between the first optical assembly and the second optical assembly, the OCT measuring light is directed only through the first optical assembly and not through the second optical assembly for illuminating the object region. In case the OCT beam splitter is arranged between the second optical assembly and the entry region of the wavefront sensor, the OCT measuring light traverses the first optical assembly as well as the second optical assembly for illuminating the object region. The OCT measuring light may interact with the OCT beam splitter, wherein the interacting may for example comprise a transmitting or reflecting. The OCT beam splitter may be configured to arrange the beam path of the OCT measuring light such that it is identical, at least in a portion thereof, with the beam path of the measuring light, which is used for an analysis of the wavefront. Thereby, the measuring light, which is used for the analysis of the wavefront may traverse or be reflected by components of the system which are also traversed by OCT measuring light or at which also OCT measuring light is reflected, wherein the optical components of the system may comprise the first optical assembly. Additionally, the components may also comprise the second optical assembly. Thereby, a set-up, which is cost-effective and compact in size may be obtained.
Optical coherence tomography (OCT) is a method based on interferometry for obtaining structural information of an object in a volumetric portion by reflecting light at different depths of an object under examination.
The OCT light source may be configured to provide OCT measuring light having wavelengths in the visible and/or near infrared range of wavelengths, wherein a bandwidth of the OCT light source is adjusted such that a coherence length of the OCT measuring light, which is emitted from the OCT light source, is between several micrometers and several tenths of micrometers. A portion of the OCT measuring light, which is emitted from the OCT light source is guided along an OCT beam path which comprises mirrors, lenses and/or fiber optics to an object, which is located in the object region. The OCT measuring light penetrates into the object, depending on the wavelengths and the material within the object, to a certain penetration depth. A portion of the penetrated OCT measuring light is reflected depending on a reflectivity within the object and is superimposed on a second portion of OCT measuring light, which has been emitted from the OCT light source and which has been reflected at a reference surface. The superimposed light is detected by a detector and converted into electrical signals, which correspond to an intensity of the detected superimposed light. Due to a comparatively short coherence length of the OCT measuring light, constructive interference is only observed when a difference between the optical path which has been traveled by the OCT measuring light to and back from the object and the optical path which has been traveled by the second portion of the light, which has been emitted by the OCT light source and has been reflected by the reference surface, is less than the coherence length of the OCT measuring light.
Different embodiments provide different variants of an OCT system. The different variants of the OCT system are different from each other in the way, structural information is obtained from a scanning along a depth direction (axial direction) as well in the way the superimposed light is detected. According to an embodiment of a time domain OCT (TD-OCT), the reference surface, at which the second portion of light, which has been emitted by the light source, is reflected, is displaced for obtaining structural information of the object from different depths. In this case, an intensity of the superimposed light may be detected by a photo detector.
In Frequency-Domain-OCT (FD-OCT), the second portion of the OCT measuring light, which is emitted by the OCT light source is also reflected at a reference surface. However, the reference surface does not have to be displaced for obtaining structural information from different depths within the object. Rather, superimposed light is spectrally dispersed into spectral portions by a spectrometer, wherein the spectral portions are detected for example by a position sensitive detector, such as a CCD camera. Through a Fourier-Transform of the obtained spectrum of the superimposed light, structural information of the object along the depth direction is obtainable (Fourier-Domain-OCT).
Further variants of FD-OCT is Swept-Source-OCT (SS-OCT). A spectrum of superimposed light is sequentially recorded by continuously varying a mean wavelength of OCT measuring light having a very narrow band width. At the same time, the superimposed light is recorded by using a photo diode.
The OCT system may for example be used to inspect the structure of an anterior chamber or posterior chamber of the human eye, or the retina of the human eye.
According to an embodiment, the measuring system for ophthalmic surgery further comprises at least one scanning mirror, which is pivotably arranged between the OCT light source and the OCT beam splitter for scanning the OCT measuring light over the object region. The OCT system may further comprise collimating optics for collimating OCT measuring light, which is generated by the OCT light source. By pivoting the at least one scanning mirror, the collimated OCT measuring light may be guided as a focused OCT measuring beam over the object region. Thereby, structural information may be obtained from a laterally extended portion of the object region. The system may comprise more than one scanning mirror, such as two scanning mirrors, which are pivotable about different axes.
According to an embodiment, the at least one scanning mirror, the second lens group of the first optical subassembly and the second optical subassembly are configured and arranged to image a region close to the at least one scanning mirror onto a region close to the mirror surface. The first optical assembly comprises, as described above, the first optical subassembly and the second optical subassembly, wherein the first optical subassembly comprises a second lens group. The second lens group of the first optical subassembly and the second optical subassembly may form an afocal system for imaging a region which is located close to the scanning mirror to a region, which is located close to the mirror surface.
A detailed description of the design and arrangement of the scanning mirrors, the mirror surface and how the region close to the at least one scanning mirror is imaged onto the region close to the mirror surface by the first optical subassembly and the second optical subassembly is given in US 2009/0257065, the whole contents of which is incorporated herein by reference in its entirety.
The mirror surface is arranged between the first lens group of the first optical subassembly and the second lens group of the first optical subassembly in the beam path of the measuring light for analyzing a wavefront. The mirror surface, which is for example part of a folding mirror may reflect the measuring light such that it traverses a further lens such as an objective lens of a microscope on the path to the object region. For an optimal adjusted system, a center of the at least one scanning mirror is imaged onto a center of the mirror surface by the second lens group of the first optical subassembly and by the second optical subassembly. Such an optical imaging process has the advantage that for different pivoting positions of the at least one scanning mirror, the OCT measuring light which emanates from a point on the scanning mirror is imaged onto a point in the center of the mirror surface, i.e. without beam walk-off. Thereby, it is prevented that the OCT measuring light fails to impinge on the mirror surface. Hence, it is possible to design the mirror surface comparatively compact in size.
In case the system comprises two scanning mirrors, which are arranged at a distance from each other, the system may be designed and adjusted such that the point in the middle of a connecting line between the two scanning mirrors is imaged onto a center of the mirror surface, or at least onto a region which is located close to the mirror surface, such as onto a region, which is located along the OCT beam path at a distance from the center of the mirror surface at most 100 times, 10 times or 2 times of the lateral extent of the mirror surface. The lateral extent of the mirror surface may be a diameter of the mirror surface. The connecting line may be oriented along the OCT beam path of the optical system, which consists of the second lens group of the first optical subassembly and the second optical subassembly. A distance of the region from the mirror surface may depend on an optical magnification of the system, which consists of the second lens group of the first optical subassembly and the second optical subassembly, such that the distance increases with a higher magnification. This dependence may be linear.
A region, which is located close to the scanning mirror may comprise spatial points, which have a distance to the scanning mirrors of the system, which is smaller, for example smaller by a factor of 10, or smaller by a factor of 5 or smaller by a factor of 2, as an extent one of the scanning mirrors, which the system comprises. The extent of the scanning mirror may be a diameter of the scanning mirror.
A region close to the mirror surface may comprise spatial points which have a distance to the mirror surface, which is smaller in particular by a factor of 10, by a factor of 5 or by a factor of 2, as an extent of the mirror surface. The distance may be measured along the OCT beam path. The mirror surface and the OCT beam path may form an angle of between 30° and 60°. The extent of the mirror surface may for example be a diameter of the mirror surface.
According to an embodiment, the measuring system for ophthalmic surgery further comprises a wavefront light source for generating measuring light which is used for analyzing the wavefront, wherein at least 80% of a total intensity of the generated measuring light consists of light having wavelengths of between 800 nm and 870 nm, or of between 820 nm and 840 nm. In other words, at least 80% of a total intensity of the generated measuring lights consists of wavelengths of between 800 nm and 870 nm, or of between 820 nm and 840 nm. The measuring light may for example be generated by a superluminescence diode (SLD). Measuring light of such a wavelength is in particular suitable to traverse the human eye until the retina such that it forms an illumination spot on the retina. Then, after diffuse reflection, the light leaves the eye and is inspected in view of its form of the wavefront by the wavefront sensor. It is advantageous to use light of these wavelength ranges, since this light is not perceived by the eye of the patient, such that the patient is not blinded and the iris of the eye of the patient does not contract. A contracted iris would impair the measurement.
According to an embodiment, at least 80% of a total intensity of the generated OCT measuring light consists of light having wavelengths between 1280 nm and 1320 nm, or of between 1300 nm and 1320 nm. OCT measuring light of these wavelengths is in particular suitable to enter a region of the interior chamber of the eye and being reflected by this region. Thereby, structural information from the anterior chamber may be obtained. Moreover, it is possible to obtain structural information from the posterior chamber of the eye and/or the retina.
For examining or observing the retina by OCT, a wavelength range between 800 nm and 870 nm is well suitable, since this light reaches the retina. In this case, spectra of the wavefront light source and the OCT light source may overlap such that at least 60%, or at least 80% of an intensity of the measuring light for the analysis of the wavefront is located in a wavelength range, in which 80% of an intensity of the OCT measuring light is located. The measuring light for the analysis of the wavefront may comprise essentially the same wavelengths as the OCT measuring light. In this case, it is possible to use a single light source which generates the measuring light for the analysis of the wavefront and also the OCT measuring light.
According to an embodiment, a least 60%, or at least 80% of a total intensity of the measuring light consists of wavelengths, which define a wavelength range of measuring light, in which at least 80% of a total intensity of the OCT measuring light is located.
In other words, a spectral intensity distribution of the measuring light and a spectral intensity distribution of the OCT measuring light are configured such that in an overlapping wavelength range of these intensity distributions, at least 60% or at least 80% of a total intensity of the measuring light is located and at least 80% of a total intensity of the OCT measuring light is located.
According to embodiments, at least 70%, or at least 90% of the intensities of the measuring light, which is used for the wavefront analysis and the OCT measuring light are not located in overlapping wavelength ranges. In other words, at least 70%, or at least 90% of a total intensity of a spectral intensity distribution is not located in an overlapping wavelength range of the spectral intensity distribution of the measuring light and the spectral intensity distribution of the OCT measuring light. Although, the measuring light, which is used for the wavefront analysis, and the OCT measuring light traverse or interact with optical components of the measuring system for ophthalmic surgery, those measuring lights may be separated from each other, for example by dichroic elements, due to their different wavelength ranges. The optical components, with which the measuring lights interact or which are traversed by the measuring lights, may for example be the first optical assembly and optionally also the second optical assembly. Thereby, it is prevented that a measurement of the wavefront influences a measurement with the OCT-system. However, both measuring lights may comprise common wavelength ranges and their spectra may overlap to a large extent.
According to an embodiment, the OCT beam splitter comprises a dichroic mirror, wherein a transmission of the dichroic mirror in a wavelength range of between 800 nm and 870 nm, or of between 820 nm and 840 nm is at least twice as high or at most half as high as the transmission in a wavelength range of between 1280 nm and 1340 nm or of between 1300 nm and 1320 nm.
According to embodiments, at least 80% of an intensity of the measuring light for wavefront analysis or of the OCT measuring light is transmitted through the OCT beam splitter.
According to an embodiment, the OCT beam splitter comprises a dichroic mirror, wherein a reflectivity of the dichroic mirror in a wavelength range of between 1280 nm and 1340 nm, or of between 1300 nm and 1320 nm is at least twice as high or at most half as high as a reflectivity in a wavelength range of between 800 nm and 870 nm, or of between 820 nm and 840 nm.
According to an embodiment, at least 80% of an intensity of the measuring light for wavefront analysis or of the OCT measuring light is reflected by the OCT beam splitter.
The dichroic mirror may be coated with layers of materials having different dielectric constants. These layers may be configured such that constructive interference is generated for the reflected measuring light or the transmitted measuring light in case the measuring light impinges onto the dichroic mirror.
According to an embodiment, a major part, or at least 70% of an intensity of OCT measuring light which impinges onto the OCT beam splitter is reflected at the OCT beam splitter. Additionally or alternatively, a major part, or at least 70% of an intensity of measuring light for wavefront analysis, which impinges onto the OCT beam splitter, is transmitted through the OCT beam splitter.
BRIEF DESCRIPTION OF THE DRAWINGS
The forgoing as well as other advantageous features of the invention will be more apparent from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. It is noted that not all possible embodiments of the present invention necessarily exhibit each and every, or any, of the advantages identified herein.
FIG. 1A schematically illustrates an embodiment of an optical measuring system, wherein an illumination beam path or wavefront beam path, respectively, is illustrated;
FIG. 1B schematically illustrates the embodiment, which is illustrated in FIG. 1A , wherein an object beam path is illustrated;
FIG. 1C schematically illustrates a section of the embodiment illustrated in FIGS. 1A and 1B of an optical measuring system;
FIG. 2A schematically illustrates a further embodiment of an optical measuring system, wherein an illumination beam path or wavefront beam path, respectively, is illustrated;
FIG. 2B chematically illustrates the embodiment, which is illustrated in FIG. 2A , wherein an object beam path is illustrated;
FIG. 3 chematically illustrates a further embodiment of an optical measuring system;
FIG. 4 schematically illustrates a further embodiment of an optical measuring system;
FIG. 5A schematically illustrates a further embodiment of an optical measuring system, wherein an illumination beam path or wavefront beam path, respectively, is illustrated;
FIG. 5B schematically illustrates the embodiment, which is illustrated in FIG. 5A , wherein an object beam path is illustrated;
FIG. 6 shows an optical measuring system according to a further embodiment, wherein an OCT beam path is illustrated; and
FIG. 7 shows an optical measuring system according to a further embodiment, wherein an OCT beam path is illustrated.
DETAILED DESCRIPTION OF THE INVENTION
In the exemplary embodiments described below, components that are alike in function and structure are designated as far as possible by alike reference numerals. Therefore, to understand the features of the individual components of a specific embodiment, the descriptions of other embodiments and of the summary of the invention should be referred to.
FIG. 1A schematically illustrates an optical measuring system 1 according to an embodiment. Measuring system 1 comprises a light source 3 , which generates measuring light 5 . Measuring light 5 is collimated by collimating optics 7 for generating measuring light 9 , which substantially consists of plane wavefronts. Measuring light 9 is reflected at the beam splitter 11 and traverses cemented element 13 . The measuring light, which is converged by cemented element 13 passes through aperture 15 and is deflected by 180° by reflector 17 which comprises two mirror surfaces 17 ′ and 17 ″, which are oriented orthogonal to each other. Thereby, measuring light 9 is deflected in a substantially reverse direction and displaced in a lateral direction, i.e. in a direction which is perpendicular to a propagation direction of the measuring light 9 .
In further embodiments, the reflector 17 may be a corner cube. The corner cube comprises a body made of glass, having the form of a three-sided pyramid. The outer surfaces of the pyramid consists of isosceles, right-angled triangles, wherein each pair of these triangles is oriented perpendicular to each other. Furthermore, the corner cube comprises a basis surface, which is in the form of an equilateral triangle. In case the corner cube is used in the measuring system, the measuring light 9 is reflected at the three isosceles, right-angled, triangular surfaces.
The reflector 17 is displaceable in directions which are denoted by the double arrow 20 . The aperture 15 is arranged in a focal region of the cemented element 13 , wherein the position of the cemented element is independent of a displacement position of the reflector 17 .
The measuring light 9 , which is reflected by the reflector 17 , traverses a cemented element 19 , whereby convergent measuring light is formed. In the plane 21 , the measuring light 9 is substantially converged to a point, a crossover, and continues as a divergent measuring light. The divergent measuring light 9 traverses a further cemented element 23 and is transformed into plane wavefronts. The plane measuring light 9 traverses a quarter wave plate 24 and impinges onto an eye 25 in the form of a plane wavefront. The pupil of the human eye 25 is located in the object plane 28 . The image of the iris is referred to as the pupil of the eye 25 . Typically, the pupil is located about 2.7 to 3 mm behind the vertex of the cornea 33 . In this embodiment, the object plane 28 is located at the focal plane 29 of the first optical assembly 31 , which consists of the cemented element 23 and the cemented element 19 . Hence, the pupil of the eye 25 is located in the focal plane 29 .
The reflector 17 may be configured to be displaceable or movable along a direction, which is parallel to the optical axis of the first optical assembly ( 31 ) and/or the optical axis of the second optical assembly ( 13 ). In particular, the reflector may be configured such that it is displaceable or movable forward and backward parallel to the optical axis of the first optical assembly ( 31 ) and/or the optical axis of the second optical assembly ( 13 ).
Measuring light 9 traverses the cornea 33 and the lens 35 of the eye 25 , and is focused onto a spot 37 on the retina 39 . At the beam splitter 11 , the measuring light consists of plane wavefronts, i.e. of a bundle of parallel light ray beams. Measuring light is imaged onto a spot 37 on the retina of the eye 25 when the optical components are at a fixed position relative to each other only in case of an emmetropic eye having no spherical aberration. In this case, the reflector is positioned such that the total system consisting of the three optical assemblies 23 , 19 and 13 is an afocal system. However, in case the eye has a spherical aberration, it is possible to displace the reflector 17 or the corner cube 17 , respectively, along a direction, which is indicated by double arrow 20 , for generating slightly convergent measuring light 9 or slightly diverging light 9 , which is incident on the eye 25 . Thereby, it is possible, even in case the eye has a spherical aberration, to generate an illumination spot of the measuring light on the retina, which is as small as possible. By displacing the corner cube 17 along a direction, which is indicated by double arrow 20 , an optical path of the measuring light between the cemented element 13 and the cemented element 19 is varied. Therefore, in case of a spherical aberration of the eye 25 being within a certain range, measuring light 9 is focusable on a point on the retina 39 of the ametropic eye 25 .
The illumination spot 37 is a diffuse light source on the retina 39 of the eye 25 which emits light 41 , which consists of substantially spherical wavefronts. Light 41 traverses the vitreous body, the lens 35 and the cornea 33 and forms light 43 . Depending on optical properties and the shape of the lens 35 and the cornea 33 , a wavefront of the light 43 deviates from a plane wavefront. The form of the wavefronts, which form light 43 , is indicative of an ametropia of the optical components or the interfaces of the eye 25 , i.e. for example of the optical properties and the form of the lens 35 and the cornea 33 .
Light 43 traverses cemented element 23 and forms convergent light. In a spatial region of the plane 21 , in which an image of the retina is formed, light 43 is converged to a minimum extent and thereafter diverges. Furthermore, measuring light 43 traverses cemented element 19 , is reflected and laterally displaced by reflector 17 , passes aperture 15 , traverses cemented element 13 and forms light, which substantially consists of plane wavefronts. A deviation of the wavefronts of the measuring light 43 from plane wavefronts is indicative of an ametropia of the eye 25 .
Measuring light 43 enters the entry region 45 of a Hartmann-Shack sensor 47 . The entry region 45 is formed by an array of microlenses, wherein in a common focal plane of the microlenses, an electronic imaging sensor such as a chip of a CCD camera is arranged. The electronic imaging sensor comprises a plurality of pixels, each of which converts intensity values of incident light into electrical signals. The electrical signals are transmitted via data line 49 to a processing unit, which is not illustrated. For each of the microlenses of the array of microlenses of the Hartmann-Shack sensors 47 , the processing unit determines a displacement position of the light, which is focused by the respective microlens. Thereby, a form of a wavefront of the measuring light 43 in the entry region 45 of the Hartmann-Shack sensor is determinable. With reference to FIG. 1B , it is described, that a region of the focal plane 29 is imaged onto the entry region 45 of the Hartmann-Shack sensor 47 . Thereby, a form of a wavefront of light 43 , which is emitted from the eye 25 is determinable. With reference to FIG. 1B , further properties and advantages of the optical measuring system 1 are described. The pupil of the eye 25 in the object plane 28 is arranged in the focal plane 29 of the first optical assembly 31 , which consists of the cemented elements 23 and 19 . Three light beams 53 a , 53 b , 53 c , emanate from a focal point 53 in the focal plane 29 along the object beam path, traverse the quarter wave plate 24 and the cemented element 23 and are converged to a minimum extent in an intermediate image region 55 . Beams 53 emanate from the intermediate image region 55 as divergent beams, traverse cemented element 19 and exit the cemented element 19 as substantially parallel beams 53 a ′, 53 b ′, 53 c ′. The parallel beams 53 a ′, 53 b ′, 53 c ′ are reflected and laterally displaced by reflector 17 , pass the aperture 15 , traverse cemented element 13 and are focused to a point after having traversed the beam splitter 11 . This point is defined by the optical axis of the measuring system 1 and the entry region 45 of the Hartmann-Shack sensor 47 . Thereby, a point in the focal plane 29 is imaged onto a point in the entry region 45 of the Hartmann-Shack sensor 47 . Displacement of the corner cube 17 along a direction, which is indicated by double arrow 20 does not modify this imaging properties, since light beams, which emanate from a point in the focal plane 29 are oriented parallel between cemented element 19 and cemented element 13 , where the reflector 17 is arranged in the beam path. Hence, a form of a wavefront, which exits from an ametropic or emmetropic eye may be inspected with high precision.
FIG. 1C schematically illustrates a portion of the optical measuring system 1 of the schematically illustrated embodiment of FIGS. 1A and 1B . The light beams 53 a , 53 b and 53 c emanate from the focal point 51 , traverse cemented element 23 and are focused onto the intermediate image region 55 . From the intermediate image region 55 , three light beams emanate and are deflected by cemented element 19 such that three parallel light beams 53 a ′, 53 b ′ and 53 c ′ are formed, which run parallel to the optical axis 10 . Cemented elements 23 and 19 form the first optical assembly 31 , as described above. A focal length f of the first optical assembly 31 may be determined as described in the following:
The light beam 53 a ′, which is parallel to the optical axis 10 is extended in a direction towards the focal plane 29 and beyond the focal plane 29 such as illustrated by dashed line 55 a ′. Accordingly, the light beam 53 b , which is incident on the first optical assembly 31 and which is transformed into beam 53 a ′ after having traversed the optical system 31 , is extended beyond focal plane 29 , such as illustrated by dashed line 55 a . The line 55 a and the line 55 a ′ intersect in a point 57 a . The point 57 a is located in a principal plane 59 of the first optical assembly 31 . The principal plane 59 is located at a distance f away from the focal plane 29 , which is parallel to the principal plane 59 . In the principal plane, there is also located point 57 c , which is analog to point 57 a , wherein the point 57 c is defined by the intersection of lines 55 c ′ and 55 c . Hence, light beams 53 a and 53 c appear to be refracted at points 57 a or 57 c , respectively, which are located in the principal plane 59 . After having traversed the first optical assembly 31 , light beams 53 a and 53 c run parallel to the optical axis.
The light beams 53 a ′, 53 b ′ and 53 c ′ are reflected by corner cube 17 , as schematically illustrated, and are focused by cemented element 13 onto the entry region 45 of the wavefront sensor 47 . The entry region 45 is formed by those surfaces of the microlenses 46 , which are located closest to the cemented element 13 . An object region 28 ′ in the object plane 28 in the focal plane 29 of the first optical assembly 31 is therefore imaged onto the entry region 45 of the wavefront sensor 47 . Each of the microlenses 46 has a focal length 1 . At a distance 1 from the entry region 45 of the wavefront sensor 47 , there is arranged a CCD 48 for a position sensitive detection of light intensities. As described above, a detection of a distribution of light intensities and an analysis thereafter allows to determine a form of a wavefront of the measuring light, which emanates from the object region 28 ′. The object region 28 ′ in the focal plane 29 of the first optical assembly 31 is located at a distance d away from an optical surface of the first optical assembly 31 , wherein this optical surface is the optical surface which is closest to the focal region 29 . In the exemplary embodiment, which is illustrated, the distance d is about 2.5 times the focal length f of the first optical assembly 31 .
The optical measuring system 1 is especially suited for eye surgery, such as for example cataract surgery. The cornea or the pupil of the eye under surgery is arranged at the object region 28 ′. The distance d between the cornea or the pupil of the eye under inspection and a component of the first optical assembly 31 is 220 mm in the exemplary embodiment 1 . Hence, the surgeon has enough working space for performing surgical operations with his hands.
The embodiment 1 of an optical measuring system, as illustrated in FIGS. 1A , 1 B and 1 C, may be mounted at a fixed position relative to an optical microscopy system. For example, the optical measuring system is supported upstream of the objective lens of the optical microscopy system in a beam path of measuring light which emanates from the object under inspection. In this embodiment, measuring light 43 , which emanates from the object region 28 ′, may be reflected by a folding mirror 61 , which is schematically indicated. After reflection at the folding mirror 61 , the measuring light is incident on the entry region 45 of the wavefront sensor 47 after having traversed the first optical assembly 31 and being reflected at the corner cube 17 and having traversed the cemented element 13 . In FIGS. 1A and 1B , the position of the folding mirror 61 is indicated. Another part of the light, which emanates from the object region 28 ′ is guided through an objective lens of the microscopy system for performing microscopic imaging. Therefore, it is possible for a surgeon to obtain a microscopic image of an object under surgery as well as to conduct an analysis of a form of a wavefront of measuring light, which emanates from the object region 28 ′. According to embodiments, the folding mirror 61 is located close to the objective lens of the microscopy system. Thereby, a free working space is reduced as little as possible.
FIGS. 2A and 2B schematically illustrate a further embodiment 1 a of an optical measuring system. Some components of the optical measuring system 1 a are analog to components of the optical measuring system 1 , which is illustrated in FIGS. 1A , 1 B and 1 C. Thereby, for a detailed description of these components, it is referred to the corresponding description of the embodiment 1 . For example, cemented elements 19 a and 13 a of the embodiment 1 a correspond to cemented elements 19 and 13 of the embodiment 1 . Furthermore, light source 3 , collimating optics 7 and wavefront sensor 47 of the embodiment 1 correspond to light source 3 a , collimating optics 7 a and wavefront sensor 47 a of the embodiment 1 a.
Unlike embodiment 1 of the optical measuring system, which is illustrated in FIGS. 1A , 1 B and 1 C, and which comprises cemented element 23 , the embodiment 1 a , which is illustrated in FIGS. 2A and 2B comprises a lens group 23 a which consists of lens system 63 a and lens system 65 a . Furthermore, embodiment 1 a does not comprise a reflector 17 or a corner cube 17 , respectively, as is the case for embodiment 1 . Rather, aperture 15 a , cemented element 13 a , beam splitter 11 a , collimating optics 7 a , light source 3 a and the wavefront sensor 47 a are arranged at a fixed position relative to each other and may together be displaceable in a direction along the optical axis 10 a of the measuring system 1 a . This is illustrated by the dashed box 67 a , which is displaceable along directions, which are indicated by the double arrow 69 . As is explained with reference to embodiment 1 , which is illustrated in FIGS. 1A , 1 B and 1 C, a variation of the optical path between cemented elements 19 and 13 or 19 a and 13 a , respectively, of the measuring light, which is incident on the object region 28 ′, as well as measuring light 43 , which emanate from the object region 28 ′ allows a compensation of a spherical aberration of an eye under inspection 25 . The compensation effects the illumination as well as the analysis of the wavefront of the measuring light, which exits the eye 25 . Thereby, a dynamic measuring range of the wavefront sensor 47 may be extended.
Instead of providing a displaceable unit 67 a for this purpose in the embodiment, there may be provided an arrangement by using a reflector 17 or a corner cube 17 , respectively, as is illustrated in FIGS. 1A and 1B in a corresponding way. Accordingly, the embodiment 1 of the optical measuring system, as illustrated in FIGS. 1A , 1 B and 1 C may not comprise a reflector 17 . Instead, the components aperture 15 , cemented element 13 , beam splitter 11 , collimating optics 7 , light source 3 and wavefront sensor 47 may be supported at a fixed position relative to each other and are designed to be displaceable together along the optical axis 10 , such as it is illustrated in FIGS. 2A and 2B in a corresponding way. These components also may be designed not to be displaceable. In case these components are not displaceable, there is provided a wavefront sensor 47 having a large dynamic range since in this case a pre-compensation is not possible when eyes having a spherical aberration are inspected.
In the object region 28 ′ in the object plane 28 a within the focal plane 29 a , the cornea 33 or the pupil of an eye 25 of an emmetropic eye without spherical aberration is arranged. The light 5 a , which is generated by the light source 3 a is transformed by collimating optics 7 a into measuring light 9 , which substantially consists of plane wavefronts. Measuring light 9 is incident as plane wavefront on the eye 25 after having been reflected by beam splitter 11 a , having traversed cemented element 13 a , having passed aperture 15 a , having passed the cross-over, having traversed cemented element 19 a , having passed the cross-over of the measuring light 9 in plane 21 a , having traversed lens system 65 a and having traversed lens system 63 a . The ametropic eye, having no spherical aberration, focuses measuring light 9 onto a point 37 of the retina 39 of the eye 25 . From point 37 , spherical wavefronts emanate and exit the eye as measuring light 43 having plane wavefronts in the object region 28 ′ after having traversed the vitreous body, the lens 35 and the cornea 33 . Measuring light 43 traverses lens system 63 a , traverses lens system 65 a , traverses cemented element 19 a , traverses cemented element 13 a and traverses beam splitter 11 a and is incident on the wavefront sensor 47 a . There, the CCD detector, which is not illustrated, records distribution of light for determining a form of a wavefront of measuring light 43 which emanates from the object region 28 ′.
The working distance d between the object region 28 ′ and a surface of the lens system 63 a , which is located closest to the object region 28 ′ is about three times as large as the focal length f of the first optical assembly 31 a , which consists of the lens system 63 a , lens system 65 a and cemented element 19 a . Thereby, embodiment 1 a of the optical measuring system provides a sufficiently large working distance d for providing sufficient free working space for performing surgical operations.
FIG. 2B illustrates embodiment 1 a of the optical measuring system, wherein an object beam path, i.e. a beam path, which emanates from object plane 28 a , is illustrated for demonstrating further properties of the measuring system 1 a . The pupil of the eye 25 is arranged in the object plane 28 in the illustrated example of using the optical measuring system 1 a for examining the eye 25 . Therefore, the object beam path corresponds to a pupil beam path. Light beams 53 a , 53 b and 53 c , of light 43 , which emanate from a focal point 51 a are transformed by lens system 63 a into light beams 53 a ″, 53 b ″ and 53 c ″, each of which runs parallel to the optical axis 10 a of the optical measuring system 1 a . The focal point 51 a is also located in the object region 28 a ′. Hence, the distance between the principal plane 63 a ′ of the lens system 63 a and the object region 28 a ′ is equal to the focal length f ( 63 a ) of the lens system 63 a . The focal length f ( 63 a ) of the lens system 63 a substantially corresponds to a working distance d between the object region 28 a ′ and a surface of the lens system 63 a , which is located closest to the object region 28 a ′. Lens system 65 a and cemented element 19 a are arranged at a distance along the optical axis 10 , which correspond to a sum of their focal length, i.e. f( 65 a )+f( 19 a ). Thereby, the lens system 65 a and the cemented element 19 a form a so-called Kepler telescope. The Kepler telescope is an example of an afocal system, which transforms incident parallel light beams into outgoing parallel light beams. Accordingly, the parallel light beams 53 a ″, 53 b ″ and 53 c ″ are transformed by lens system 65 a and cemented element 19 a into parallel light beams 53 a ′, 53 b ′ and 53 c ′. After light beams 53 a ′, 53 b ′ and 53 c ′ have traversed cemented element 13 a , they are focused onto the entry region 45 a of the wavefront sensor 47 a . Thereby, the object region 28 a ′ is imaged onto the entry region 45 a of the wavefront sensor. Since the light beams between the cemented element 19 a and the cemented element 13 a are parallel, such an imaging is independent from a modification of the optical path of the measuring light between the cemented elements 19 a and 13 a . Such a modification is achieved by displacing the system 67 a , along directions, which are indicated by arrow 69 .
FIG. 3 shows a further embodiment 1 b of an optical measuring system. The structure and the orientation of the elements 63 b , 65 b , 19 b , 13 b , 11 b , 7 b , 3 b and 47 b , relative to each other, substantially correspond to the structure and the relative arrangement of the elements 63 a , 65 a , 19 a , 13 a , 11 a , 7 a , 3 a and 47 a , respectively, which are illustrated in FIGS. 2A and 2B . Compared to the embodiment illustrated and described so far, the optical measuring system 1 b comprises further lens elements 71 , 73 and 75 , which are arranged in this order between the object region 28 b ′ in the focal plane 29 b of the first optical assembly 31 b which consists of the lens system 63 b , the lens system 65 b and the cemented element 19 b . The lens element 71 comprises a focal length of 40 mm, the lens element 73 comprises a focal length of 18.5 mm and the lens element 75 comprises a focal length of 75 mm. These lens elements 71 , 73 and 75 are arranged to inspect an aphakic eye 25 , i.e. an eye, the lens of which has been removed and which is therefore omitted in FIG. 3 . Light beams 43 a , 43 b and 43 c are illustrated, which diverge from a point 37 of the retina 39 of the eye 25 and exit the eye 25 . In the illustrated embodiment, the aphakic eye has 19 diopters. The divergent light beams 43 a , 43 b and 43 c , which emanate from the object region 28 b ′ and which represent spherical wavefronts, are imaged by the optical imaging system of the optical measuring system 1 b as parallel wavefronts onto the entry region 45 b of the wavefront sensor. Thereby, it is possible by inserting the lens elements 71 , 73 and 75 , to further increase the dynamic measuring range of the wavefront sensor 47 , such that even aphakic eyes may be inspected in view of spherical and non-spherical aberrations. Lens elements 71 , 73 and 75 may also be provided in embodiments, which are illustrated in FIGS. 1A , 1 B, 1 C, 2 A and 2 B.
FIG. 4 illustrates a further embodiment 1 c of an optical measuring system. The optical measuring system 1 c comprises a wavefront analysis system 77 and an optical microscopy system 79 . Many of the components of the wavefront analysis system 77 have a similar structure and a similar relative orientation as the optical measuring system 1 a , as shown in FIGS. 2A and 2B . A detailed description of these components is therefore omitted. The lens system 63 a of the optical measuring system 1 a is also an objective lens 63 c of the optical microscopy system 79 in the optical measuring system 1 c . In the embodiment, shown in FIG. 4 , the objective lens 63 c has a diameter of 53 mm. Light beams 43 a , 43 b and 43 c , which emanate as parallel beams from the object region 28 c ′ in the focal plane 29 c of the first optical assembly 31 c , which consists of the lens system 19 c , the lens system 65 c and the objective lens 63 c , and which therefore form plane wavefronts, are incident on the wavefront sensor 47 c as plane wavefronts after having traversed the first optical assembly 31 c , the cemented element 13 c and the beam splitter 11 c . Parallel light beams, which emanate from the object region 28 c ′ and which therefore do not represent plane wavefronts, are incident on the wavefront sensor 47 c as non-plane wavefronts. As described above, a form of such non-plane wavefronts may be determined by detecting an intensity distribution by the wavefront sensor 47 c and by a subsequent analysis.
Furthermore, the optical measuring system 1 c allows to acquire microscopic images of the object region 28 c ′. From a point 51 in the object region 28 c ′ in the focal plane 29 c of the first optical assembly 31 c (and the objective lens 63 c ), light beams 81 and 83 emanate. Light beams 81 and 83 form a stereo angle α. Light beams 81 traverse a region 85 of the objective lens 63 c and light beams 83 traverse a region 87 of the objective lens 63 c and thereafter propagate as parallel light beams. Then, light beams 81 traverse a zoom system 89 and light beams 83 traverse a zoom system 91 . Downstream of the objective lens, 63 c , there may be located an ocular system and/or a camera for imaging the object region 28 c ′ into an image region.
In the illustrated embodiment, the distance d between a surface, which is located closest to the object region 28 c ′ of the objective lens 63 c and the object region 28 c ′ amounts to 20 cm. In the illustrated embodiment, this distance corresponds to the focal length f( 63 c ) of the objective lens. Further embodiments comprise an objective lens having a focal length of 15 cm or 25 cm. A focal length f of the optical assembly 31 c , which consists of the lens system 19 c , lens system 65 c and the objective lens 63 c , amounts to about 70 mm in the illustrated embodiment. Thereby, a sufficiently large working space is provided for conducting a surgical operation, wherein the focal length f is much smaller.
In the embodiment 1 c of the optical measuring system, which is illustrated in FIG. 4 , light rays 43 a , 43 b and 43 c , which are used for an analysis of the wavefront, traverse the objective lens 63 c of the optical microscopy system 79 . The objective lens 63 c is traversed in a region 86 of the objective lens 63 c , which is different from the regions 85 and 87 through which light beams 81 and 83 pass, which are used for microscopic imaging. Light beams 43 a , 43 b and 43 c , which are used for an analysis of the wavefront, are decoupled from further components of the optical microscopy system 79 by folding mirror 61 c.
As an alternative to this method of decoupling, light beams 43 a , 43 b and 43 c may be decoupled between the object region 28 c ′ and the objective lens 63 c of the optical microscopy system 79 through a folding mirror 61 , which is indicated by a dashed line. Thereby, embodiment 1 of an optical measuring system, which is illustrated in FIGS. 1A , 1 B and 1 C, may be combined with the optical microscopy system 79 or with the embodiment 1 d , which is illustrated in FIGS. 5A and 5B . This is illustrated in FIGS. 1A , 1 B, 5 A and 5 B by folding mirror 61 .
Instead of simultaneously displacing the components, which are surrounded by box 67 c of the wavefront analysis system 77 , the optical path between lens system 19 c and cemented element 13 c may be varied by providing a displaceable corner cube 17 , such as is illustrated in FIGS. 1A and 1B . This way of pre-compensation of a spherical aberration of an eye under inspection may be used in combination with the decoupling of measuring light 47 with folding mirror 61 c as well as the decoupling of the measuring light 43 by using folding mirror 61 .
The optical measuring system 1 c provides to the surgeon a microscopic image of the anterior chamber of the eye and at the same time allows to analyze a wavefront of measuring light which is emitted from the eye. Thereby, an accurate measurement of a refraction is possible by using the wavefront sensor. Due to the large working space, the wavefront analysis system does not have to be removed during the surgical operation and does not have to be inserted in case it is needed. Thereby the handling is significantly simplified and the wavefront analysis system does not need to be pivotably supported.
The object region 28 c ′ is also located in the focal plane of the objective lens 63 c . Downstream of the objective lens 63 c , light beams 81 and 83 which emanate from a point 51 of the object region 28 c ′, are parallel, which result in further advantages for the subsequent components and the microscopic imaging. In the wavefront analysis system 77 of the optical measuring system 1 c , further lens elements 71 , 73 and 75 may be provided in an analogy to the embodiment 1 b of an optical measuring system, which is illustrated in FIG. 3 , for analyzing wavefronts, which exit from an aphakic eye. Therefore, it is possible, to inspect eyes having spherical aberrations of 14 diopters, 19 diopters, 24 diopters and values therebetween. In case the lens elements 71 , 73 and 75 are not provided, eyes having spherical aberrations of at least in the range between −5 dpt and +5 dpt may be inspected by varying the optical path between elements 13 and 19 , 13 a and 19 a , or 13 c and 19 c , respectively.
The Kepler telescope, which is formed by the lens system 65 a and the cemented element 19 a , which is illustrated in FIGS. 2A and 2B , may be replaced by a Galilei telescope or another afocal system.
According to an embodiment, the entry region of the wavefront sensor has an extent of 6.34 mm*6.34 mm. In alternative embodiments, other extents may be provided. The light source 3 , 3 a , 3 b and 3 c , respectively, typically comprises a superluminescence diode and acts as a point light source. Also, the optical measuring system 1 c may be designed such that an optical path is variable for a pre-compensation of a spherical aberration. Optical elements, which interact with a polarization of light such as for example quarter wave plates or a beam splitter, which is configured as a polarization beam splitter, may be used for separating the reflected light, which is generated at optical surfaces from measuring light, which emanates from the illumination spot 37 on the retina 39 .
FIGS. 5A and 5B schematically illustrate a further embodiment of an optical measuring system 1 d . Again, in FIG. 5A , an illumination beam path or a wavefront beam path is illustrated and in FIG. 5B , an object beam path is illustrated. The optical measuring system 1 d comprises a first optical assembly 31 d , which in this embodiment is a cemented element, a second optical assembly 13 d which in this embodiment is a cemented element and a wavefront sensor 47 d.
For illuminating the eye 25 , the optical measuring system 1 d further comprises a light source 3 d , which emanates light 5 d . Light 5 d is converted by beam shaping optics 7 d into convergent measuring light 9 and focused into the region of the aperture 12 d after being reflected at the beam splitter 11 d . In case an emmetropic eye is inspected, aperture 12 d is arranged in a focal plane of cemented element 31 d . After having traversed the cemented element 31 d , measuring light 9 substantially comprises plane wavefronts which are incident on the eye 25 . After having traversed the cornea 33 , the natural lens 35 , measuring light 9 is focused onto a point 37 of the retina 39 .
Light 41 emanates from point 37 and form measuring light 43 after having traversed the natural lens 35 and the cornea 33 . In case of an emmetropic eye, measuring light 43 substantially consists of plane wavefronts. The pupil of the human eye is arranged in the object plane 28 d in the object region 28 d ′. The distance between the object plane 28 d and the cemented element 31 d is denoted as distance d and the focal length of the cemented element 31 d is denoted as distance f in FIG. 5A . Measuring light 43 , which emanates from the object region 28 d ′ traverses cemented element 31 d , passes the cross-over in a plane of the aperture 12 d , traverses beam splitter 11 d , traverses cemented element 13 d and impinges onto the entry region 45 d of the wavefront sensor 47 d as plane wavefronts in case of an emmetropic eye.
Cemented element 31 d and cemented element 13 d form an afocal system, such as for example a Kepler system. For achieving this, the cemented element 31 d and the cemented element 13 d are arranged at a distance along the optical axis 10 d , wherein the distance corresponds to the sum of the focal length of the cemented element 31 d and the cemented element 13 d.
Through displacing of the component along the optical axis 10 d which are surrounded by box 14 d , as indicated by double arrow 16 d , (i.e. the light source 3 d , the beam shaping optics 7 d , the beam splitter 11 d and the aperture 12 d ), it is possible even in case an eye having a spherical aberration is investigated, to generate an illumination spot 37 which has a small extent on the retina 39 of the eye 25 . In this case, measuring light 43 , which emanates from the object region 28 d ′ does not consists of substantially plane wavefronts. Therefore, it is possible for the wavefront sensor 47 d , which is used in embodiment 1 d , to measure wavefronts having a comparatively small curvature.
FIG. 5B illustrates an object beam path of the optical measuring system 1 d . Light beams, which emanate from a point 28 d ″ in the object region 28 d ′ in the object plane 28 d traverse cemented element 31 d , beam splitter 11 d and cemented element 13 d and impinge onto a point 45 d ′ in the entry region of the wavefront sensor 47 d . It is obvious that the distance d between cemented element 31 d and the object plane 28 d is much larger than the focal length f of the cemented element 31 d.
The optical measuring system 1 d may comprise a folding mirror 61 , which allows to combine the optical measuring system 1 d with an optical microscopy system 79 , as illustrated in FIG. 4 . In FIG. 4 , the position of the folding mirror 61 is schematically indicated.
FIG. 6 schematically illustrates an optical measuring system 1 e according to an embodiment. The optical measuring system 1 e , as illustrated in FIG. 6 , is configured to inspect an object region 28 e ′ by an analysis of a wavefront which emanates from an object region and by optical coherence tomography (OCT). To this effect, the measuring system 1 e , as illustrated in FIG. 6 , comprises in addition to the measuring system 1 , as illustrated in FIGS. 1A and 1B , an OCT system 93 and an OCT beam splitter 95 . The OCT system 93 comprises OCT components 97 , which comprise an OCT light source for generating OCT measuring light 99 , an optical coupler for dividing and combining OCT measuring light, a reference mirror, a spectrometer, a position sensitive detector and an analysis system.
The OCT light source emits OCT measuring light 99 which traverses collimating optics 101 and enters as collimated OCT measuring light beam a scanner, which comprises two scanning mirrors 103 and 105 . The scanning mirrors 103 , 105 are pivotable about axes, which are oriented perpendicular to each other for scanning OCT measuring light 99 over the object region 28 e ′. For illustrative purposes, the elements 97 , 101 and 103 are illustrated in FIG. 6 as being tilted about the connecting line between the two scanning mirrors 103 and 105 . The OCT measuring light 99 may comprise as a major part wavelengths of light between 1290 nm and 1330 nm.
FIG. 6 shows in an exemplary way three light beams of OCT measuring light which are reflected at a point A of the scanning mirror 105 when the scanning mirror is positioned at three different pivoting positions which are obtained by pivoting the pivoting mirror about a pivoting axis which is oriented perpendicular to the paper plane and which intersects point A. The light beams of OCT measuring light 99 are incident on the OCT beam splitter 95 which comprises a dichroic mirror 96 . The dichroic mirror 96 comprises layers which are deposited on a mirror surface of the dichroic mirror 96 , wherein the layers have different dielectric properties for reflecting the incident OCT measuring light 99 with a high effectivity and to transmit only a small portion, such as less than 30%. The OCT measuring light 99 traverses the lens 19 e after having been reflected at the dichroic mirror 96 . For example, the lens 19 e may be designed as a cemented element and an additional individual lens. Then, the OCT measuring light 99 traverses cemented element 23 e . Cemented element 23 e and lens 19 e form the first optical assembly 31 e . The first optical assembly 31 e images the point A in the center of the scanning mirror 105 onto a point A′ between the first optical assembly 31 e and the object region 28 e ′, in which the focal point 51 e of the first optical assembly 31 e is located. Similarly, a point P in the center of the connecting line between the scanning mirror 103 and the scanning mirror 105 is imaged by the first optical assembly 31 e onto a point P′. At this position, an optional folding mirror 61 may be located for deflecting OCT measuring light 99 , which propagates towards the object region 28 e ′ and OCT measuring light, which returns from the object region 28 e ′. This may be advantageous in case the optical measuring system 1 e is used in combination with an optical microscope. In this case a folding mirror 61 may be arranged in the beam path of the microscope between the main objective lens of the microscope and the object region 28 e′.
In such a case, it may be advantageous that the optical measuring system 1 e images the point P onto the point P′, which is located on the folding mirror 61 , since for different pivoting positions of the mirrors 103 , 105 , a walk-off of the point P′ from the center of the folding mirror 61 is minimized. Hence, it is possible to design the folding mirror 61 compact in size such that vignetting of the beam path of the microscope is prevented. In order to achieve this, all scanning mirrors of a scanner (in this case the scanning mirrors 103 and 105 ) have to be arranged as close as possible to the point P and the folding mirror 61 has to be located as close as possible to the point P′.
The three light beams of OCT measuring light which correspond to three different pivoting positions of the scanning mirror 105 are incident at the three different points within the object region 28 ′ at which they interact with the object, which is arranged in the object region 28 e ′. In FIG. 6 , there are shown only three scanning points. However, by continuously pivoting the scanning mirrors 103 , 105 the entire object region 28 e ′ is scanned.
OCT measuring light, which emanates from the object region 28 e ′ has been reflected at different layers within the object and thereby contains structural information of the object under inspection. The reflected OCT measuring light 100 traverses cemented element 23 e , lens 19 e and a major part is reflected at the dichroic mirror 96 of the OCT beam splitter 95 . After further reflections at the scanning mirrors 105 , 103 , the returning OCT measuring light traverses collimating optics 101 and enters an optical fiber of the OCT components 97 , which is not illustrated. Then, the returning OCT measuring light is superimposed on reference light and spectrally dispersed by a spectrometer and detected by a position sensitive detector. A spectrum of the returning OCT measuring light, which is interferometrically superimposed on reference light, is processed for obtaining structural information from the lateral object region 28 e ′ of the object under inspection along a depth direction, i.e. perpendicular to the object plane 28 e.
Such as the embodiment 1 of an optical measuring system, as illustrated in FIGS. 1A and 1B , also the optical measuring system 1 e , as illustrated in FIG. 6 , comprises components for analyzing a wavefront, as described above. For simplicity of illustration, in FIG. 6 , a beam path of measuring light 9 , which is guided towards the object region 28 e ′ through cemented element 13 e , lens 19 e and cemented element 23 e , as well as returning measuring light 43 are not illustrated. These beam paths are illustrated in FIGS. 1A and 1B from which it may be seen that also in the embodiment of an optical measuring system 1 e , which is illustrated in FIG. 6 , the object region 28 ′, which may comprise the focal point 51 e of the first optical assembly 31 e is imaged onto the entry region 45 e of the Hartmann-Shack sensor 47 e.
Therefore, the embodiment 1 e allows to simultaneously inspect the object region 28 ′ by analyzing wavefronts, which emanate from this region and by acquiring OCT structural data. The wavefront light source 3 e may be configured such that a central portion of measuring light which is generated by light source 3 e is located within a range of wavelengths of about 830 nm to 870 nm. The OCT beam splitter 95 , or its dichroic mirror 96 is designed such that a substantial portion of light of a wavelength range of about 830 nm to 870 nm is transmitted. Thereby, it is possible to separate the OCT measuring light from the measuring light for inspecting a wavefront in order to reduce disturbances.
According to a further embodiment, no reflector 17 e is provided between lens 19 e and cemented element 13 e , such that a beam path of measuring light 9 , 43 which is used for an analysis of the wavefront propagates in a straight line along an optical axis of cemented elements 19 e , 23 e , i.e. an optical axis of the first optical assembly 31 e , without being deflected.
According to a further embodiment, the OCT beam splitter 95 may be arranged between the second optical assembly 13 e and the Hartmann-Shack sensor 45 e , instead of being located between the first optical assembly 31 e and the second optical assembly 13 e . This is indicated by the dashed box 95 a . Accordingly, the OCT system 93 is illustrated as an alternative with a dashed box having reference sign 93 a . This embodiment is advantageous in case structural information is to be obtained from the posterior portion of the eye by using the OCT system. This arrangement of the OCT beam splitter 95 a or the OCT system 93 a may be used when the optical measuring system does not have a reflector 17 e , as described above.
FIG. 7 schematically illustrates an optical measuring system if according to a further embodiment. The optical measuring system 1 f , as illustrated in FIG. 7 , is designed in a similar way as the optical measuring system 1 c , as illustrated in FIG. 4 , in so far as the optical measuring system if also comprises components 67 c of a wavefront analysis system 77 as well as a microscopy system 79 . The microscopy system 79 comprises an objective lens 63 c for imaging the object region 28 c ′, which is located in a focal plane 29 c , after having traversed zoom systems 89 , 91 . Also, the wavefront analysis system 77 is designed such that wavefronts, which emanate from the object region 28 c ′ or which traverse the object region 28 c ′ are inspectable in view of their form, as has been described with reference to FIG. 4 .
In addition to the functionalities of the optical measuring system 1 c , as illustrated in FIG. 4 , the optical measuring system 1 f , as illustrated in FIG. 7 , allows to inspect the structure of an object region 28 c ′ along a depth direction, i.e. perpendicular to the focal plane 29 c by using the OCT system 93 a . To this effect, the OCT system 93 a comprises similar components as the OCT system 93 , which is illustrated in FIG. 6 .
In FIG. 7 , there is schematically illustrated a beam path of the OCT measuring light 99 a for three different pivoting positions of the scanner, which consists of the scanning mirrors 103 a , 105 a . For simplicity of illustration, OCT measuring light 99 a which emanates in three different directions from the point P between the scanning mirrors 103 a , 105 a is illustrated. Alternatively, at this point P, a center of a 3D-scanner may be arranged. In case a scanner comprises more than one mirroring surface, the point P is advantageously arranged such that distances to mirror surfaces of the scanner are minimized.
Light beams of OCT measuring light 99 , which emanate from the point P, are reflected at the scanning mirror 105 a , are reflected at dichroic mirror 96 a to a major part and traverse the afocal system, which consists of the cemented element 19 c and the cemented element 65 c , and is imaged onto the point P′, which is arranged in the center of the folding mirror 61 c . Point P is imaged by the cemented element 19 c , i.e. the second optical subassembly of the first optical assembly 31 c and through cemented element 65 c , i.e. the second lens group of the first optical subassembly of the first optical assembly onto the point P′ which is located at the center of the folding mirror 61 c . Hence, for different pivoting positions of the scanner, which consists of scanning mirrors 105 a , 103 a , there is a minimal walk-off of the point P′. In case of an ideally arranged 3D-scanner having only one reflecting surface, there is expected to be no beam walk-off. This allows to design the folding mirror 61 c compact in size, such that beam paths of the microscope 81 and 83 can pass the folding mirror 61 and enter the respective zoom system of the stereo microscope system 79 .
As an alternative to the arrangement of the OCT beam splitter 95 a and the OCT system 93 a , as illustrated in FIG. 7 , these components or at least the OCT beam splitter 95 a may be arranged between cemented element 65 c and the folding mirror 61 c.
As an alternative to the embodiments, which are illustrated in FIGS. 6 and 7 , the OCT beam splitter 95 , 95 a or the dichroic mirror 96 , 96 a may be designed such that OCT measuring light 99 , 99 a may be transmitted with a higher effectivity than reflected. They further may be designed such that measuring light 9 , which is used for the measurement of the wavefront is reflected with a higher effectivity than transmitted. Hence, in alternative embodiments, the spatial arrangement of the wavefront analysis system 77 and the OCT system 93 , 93 a may be interchanged.
According to further embodiments, a range of wavelengths, which comprises 70% of a total intensity of OCT measuring light may overlap with a range of wavelengths, which comprises 70% of a total intensity of measuring light for inspecting the wavefront. Thereby, light of the same wavelength range may be used for inspecting the wavefront and for inspection by using OCT light. In this case, the OCT beam splitter 95 , 95 a , having a dichroic mirror 96 , 96 a is not necessary. In this case, it is advantageous to successively conduct a measurement for determining the wavefront and a measurement for determining the structure by using OCT. Thereby, an interference is prevented. However, it is also possible to conduct both measurements simultaneously. Optical elements having a polarization effect, such as quarter wave plates may be inserted into the beam path. For example, the elements 11 , 11 a , 11 b , 11 c , 11 d , 11 e may be configured as a polarization beam splitter.
According to further embodiments, the light beam of OCT measuring light 99 is not focused onto the object region 28 c ′, 28 e ′ but focused onto a region, which is located deeper, such as onto the retina of the eye under inspection.
While the invention has been described with respect to certain exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art. Accordingly, the exemplary embodiments of the invention set forth herein are intended to be illustrative and not limiting in any way. Various changes may be made without departing from the spirit and scope of the present invention as defined in the following claims. | The invention relates to an optical measuring system comprising a wave front sensor for characterizing a shape of a wave front of measuring light and an imaging lens, wherein the imaging lens comprises a first optical assembly and a second optical assembly for imaging an object region in an entrance region of the wave front sensor. A distance between the object region and the first optical assembly is larger than a focal length of the first optical assembly. Furthermore, the optical measuring system can comprise an optical microscopy system and optionally an OCT system for carrying out different optical examination methods at the same time. | 0 |
BACKGROUND OF THE INVENTION
The invention is concerned with a mechanism for the acceleration of the projectile of a projectile loom. It is further concerned with a projectile loom having the mechanism in accordance with the invention.
From the U.S. Pat. No. 4,922,967 a drive for the projectiles of a projectile loom is known in which a striker piece acts directly on the projectile guided in a straight guideway. The striker piece is fastened to a striker lever at the end of it remote from the torsion bar and moves along a practically circular path. The striker lever is in contact via the striker piece with the rear end of the projectile in the region of the impact face and accelerates it in a few milliseconds over a travel of a few centimeters with an acceleration of up to 30,000 m/sec 2 to velocities of up to 60 m/sec. The striker face on the striker piece as well as the impact face on the projectile are therefore subjected to heavy loads, which leads to corresponding wear.
SUMMARY OF THE INVENTION
The problem the invention seeks to solve is to create a mechanism for the acceleration of the projectile of looms which reduces the wear at the impact face of the projectile as well as at the striker face of the striker piece. In accordance with the invention the problem is solved by providing an active or passive alignment member which acts upon the striker piece and positions the striker piece in such a way that during the triggering of weft insertion a striker face on the striker piece is conformed to the shape of the impact face on the projectile.
The mechanism for accelerating the projectile of a projectile loom has a torsion-bar launching mechanism with a striker lever which, at the end of it remote from the torsion bar, includes a striker piece that acts directly upon the impact face of the projectile during launching. The projectile for the loom, which has a casing formed of a hollow body, may be partially closed at its rear end as viewed in the direction of flight. The striker piece can turn on the striker lever and has at least one striker face which is oriented by an alignment member in such a way that at the latest directly before, at or after the triggering of weft insertion the position of the striker face conforms to that of the impact face on the projectile as, for example, two faces lying in parallel or nearly in parallel. The impact energy is thereby transmitted to the projectile and uniformly distributed over its impact face. Wear of the striker face and impact face is thereby reduced.
As a further advantage, the definite positioning of the striker face permits the placement of the projectile in the launching mechanism with a small clearance between the striker face and the impact face, which reduces the blow against the impact face.
A further advantage is that during the phase of acceleration of the projectile the striker piece does not come into contact with the alignment member.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows part of the launching mechanism of a projectile loom constructed in accordance with the invention and illustrates, in broken lines, the projectile after the launching;
FIG. 2 shows a side elevation of a striker lever with its striker piece and with the projectile, in different positions during and after the launching of the projectile;
FIG. 3a shows a striker lever with a T-shaped striker piece able to turn through a certain angle;
FIG. 3b shows the striker lever with the T-shaped striker piece turned;
FIG. 3c shows a view of the striker lever in the launching direction;
FIG. 3d shows a view of the T-shaped striker piece;
FIG. 4a shows a striker lever with a U-shaped striker piece;
FIG. 4b shows a longitudinal section through the striker lever with the U-shaped striker piece;
FIG. 5 shows a further form of a turnable striker piece;
FIG. 6a shows an alignment member with the mutual positions of striker piece and projectile just prior to and, in broken lines, during weft delivery;
FIG. 6b shows the action of the alignment member on the position of the striker piece during the stressing of the striker lever;
FIG. 6c also shows the action of an alignment member on the position of the striker piece during the stressing of the striker lever;
FIG. 7 shows the position of the striker piece relative to the projectile during acceleration of the projectile;
FIG. 8 shows a spring-like alignment member;
FIG. 9 shows a further alignment member; and
FIG. 10 shows an actively moved alignment member.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a projectile accelerating mechanism 1 of a projectile loom generally indicated by reference numeral 1a but not otherwise illustrated in detail because such looms are well known to those skilled in the art. One end of a striker lever 3 is connected to the torsion bar 2 for pivotal movements therewith as the bar is torsionally stressed and unstressed. The other end of the striker lever 3 pivotally mounts a striker piece 34 forming a striker face 33. At the latest just prior to the triggering of the weft insertion the position of the latter conforms to that of the impact face 43 of the projectile 4. The projectile 4 has multiple guides in the launching direction and, after launching, enters a channel 10 formed through the shed of the loom by guide teeth 11 and in that manner carries in the weft yarn 14. The guide teeth are fitted to reed 13 of the loom. At its other end (not shown) torsion bar 2 is clamped firmly and at its other end is twisted and stressed. In FIG. 1 the spring-back of striker lever is represented by reference numeral 3' and is shown in dotted lines. The projectiles 4 are brought into the launching position, one after another, with a pivotable projectile lever 7. Projectiles 4' are moved from lever position 7', shown in dotted line, to the front of striker piece 34 on striker lever 3. In the case of known projectile looms the return transport of the projectiles 4' to the projectile lever position 7' is effected, for example, by a conveyor chain (not shown).
The launching of a projectile 4 and the turning motion of the striker lever 3 induced by torsion bar 2 are illustrated in FIG. 2. Two further positions are drawn in dotted lines at 3' and 3" and the position of reversal of the striker lever is at 3'". The launching phase has practically concluded when the striker lever 3 has pivoted through the angle α, while the striker lever 3 continues to pivot through the angle β to the position of reversal 3'". During the stressing of the striker lever it is moved back again into its starting position 3, while between the starting position 3 and at least one part of the range of angle α an alignment member 5 influences the position of striker piece 34.
In FIG. 3a striker piece 34 is supported by a bushing 35' pressed onto a pin 35 so that it can pivot on striker lever 3 and it has a T-shaped flat striker face 33 which is widened in the launching direction. In the illustrated embodiment striker face 33 is in the launching position and perpendicular to the direction of launch. Launching positions of the striker face 33 which deviate from the perpendicular are also possible, the impact face 43 on the projectile being in each case parallel or approximately parallel to the striker face 33. The alignment member acts upon at least one face of the striker piece 34. Thus the area 37, for example, is suitable as a guideface for coming into contact with the alignment member 5. The stopface 36 as represented in FIG. 3b limits the angular play δ of the striker piece 34. FIG. 3c shows a view of the striker lever 3 with the striker piece 34 in the direction of launch. An embodiment is represented in FIG. 3d of a striker piece 34 having a striker face 33 and guideface 37. The striker piece 34 is preferably shaped so that it is counterbalanced as regards its pivoting about bushing 35'.
FIGS. 4a and 4b show as a further embodiment a striker piece 34 made in the shape of a U. Functionally it is identical to the striker piece shown in FIG. 3a. The wide guideface 37 brings about a reduction in the surface pressure on the area touching the alignment member 5. A T-shaped widening of those regions of the guideface 37 which come into contact with the alignment member 5 can also be advantageously employed in the embodiment of FIG. 3d.
In FIG. 5 striker piece 34 is shaped as a turnable polygon; e.g. as a hexagon, so that the different faces of the polygon may serve; e.g. successively as the striker face 33 or the guideface 37 respectively.
FIG. 6a shows striker lever 3, associated striker piece 34 as well as the projectile 4 in the launching position. Alignment member 50 fixes the position of striker face 33 on striker piece 34 parallel or approximately parallel to impact face 43 on projectile 4. The definite position of the striker face 33 allows projectile lever 7 to place projectile 4 in the launching position so that the distance between the impact face 43 and the striker face 33 typically amounts to a fraction of a millimeter. Upon triggering, striker face 33 preferably contacts impact face 43 with a negligibly low velocity and at a negligible angle between the striker face and the impact face and projectile 4 is increasingly accelerated when the two are in mutual contact. The guidebeam 8 forces projectile 4' along a linear path in the launching direction, whereas the striker piece 34' describes a circular path. Thus, while maintaining contact striker face 33 slides vertically to the weft direction across the impact face 43.
FIG. 6b shows the striker lever 3 with the associated striker piece 34 after it has been fully stressed. It also shows different possible positions 34'", 34" and 34' of the striker piece during the stressing of the striker lever. The striker piece 34 has an angular play δ and the shown positions 34', 34" and 34'" of the striker piece were selected for illustration of the action of the guideface 51. Only one particular set of many possible positions, which are dependent upon the angular play δ, are shown.
As regards the influence upon the position of the striker piece 34, four ranges may be distinguished in the guide or alignment member 50. In the entry range σ' the distance between the guideface 51 and the circular path about the center of rotation of striker piece 34 is reduced. Following a range σ", over which a constant distance is maintained, there is a further range σ'" over which the distance is reduced. Finally, over the range σ"", the guideface 37 of striker piece 34 and guideface 51 come in contact with one another at least partially and without play to thereby fix the position of the striker piece. In the illustrated example guideface 51 of guide member 5 reduces the angular play δ of the striker piece 34 over the range σ'" in order to fix the striker piece in position free of play at range σ"". It may also be advantageous to start the reduction of the angular play δ at ranges σ' as well as π".
The striking of guideface 37 against guideface 51 during the stressing of striker lever 3 may be reduced or even eliminated if the impact angle of the two surfaces is relatively flat. The shape of guideface 37 on striker piece 34 may be subdivided into an entry range Γ, an alignment range Γ" as well as a holding range Γ'", as is shown in FIG. 3a, to enable low-impact cooperation of the two guidefaces 37 and 51.
In addition, the angular velocity of the striker lever 3 during stressing may be influenced with appropriately shaped cam discs, so that, for example, over the range where the two guidefaces 37 and 51 first make contact, the angular velocity is correspondingly low.
Impact between guidefaces 37 and 51 may be further reduced by making the alignment member 50 flexible, particularly in a direction perpendicular to the weft path of the projectile, for example, by constructing the alignment member of a soft material such as plastic or by resiliently supporting the alignment member 50.
FIG. 6c shows the striker lever 3 and the associated striker piece 34 after stressing has been concluded. It also shows different positions 34'", 34" and 34' of the striker piece during the stressing of the striker lever 3. In contrast to FIG. 6b, the range σ"" over which the position of the striker piece 34 is fixed is lacking. As a result, striker piece 34 exhibits slight angular play in its starting position.
The position of the striker piece 34 relative to the projectile 4 during the acceleration phase of the projectile 4 is shown in FIG. 7. On leaving the position 340a at the start of acceleration, the striker piece moves relative to the projectile to the position of maximum acceleration 340". The acceleration of the projectile terminates at position 340'". While maintaining contact, striker face 33 slides perpendicularly to the weft direction across impact face 43. At least from the start of acceleration at 340' to the point of maximum acceleration at 340" the center of gravity S of the striker piece in the direction of launch lies within impact face 43 of the projectile. Any tilting of the striker piece resulting in a loss of the flat, face-to-face contact should take place, at the earliest, towards the end of the acceleration of the projectile in the vicinity of position 340'".
A further embodiment of an alignment member is shown in FIG. 8. The alignment member 52 is made like a spring; e.g. a leaf spring secured to a clamping member 53. The clamping member may also be resilient so that the alignment member 52 may be a rigid body. The alignment member 52 and clamping member 53 may of course form part of alignment member 50, for example, by having the alignment member define holding range σ"".
Another embodiment of an alignment member is shown in FIG. 9. In the terminal phase of stressing striker lever 3, striker piece 34' (shown in dotted lines) meets alignment member 54 at a preferably very low angular velocity. The further pivoting of the striker lever causes alignment member 54 to align striker piece 34. Resilient properties of the alignment member in the launching direction of projectile 4 are advantageous.
As shown in FIG. 10, striker piece 34 may alternatively be aligned with an active, motor-driven alignment member 55 which, for example, in the starting position of the striker lever prior to triggering the weft insertion, adjusts the inclination of the striker piece with a linear or pivotal motion. | The mechanism for the acceleration of a projectile of a projectile loom has a torsion-bar launching mechanism (1) with a striker lever (3) which, at its end remote from the torsion bar (2), carries a striker piece (34) which, during launching, acts directly on an impact face (43) of the projectile (4). The projectile (4) for the loom has a casing formed of a hollow body and may be partially closed at the rear, as viewed in the direction of flight. The striker piece (34) can pivot on the striker lever (3) and has at least one striker face (33) which is aligned by an alignment member (5) so that at the instant just prior to triggering of the weft insertion the position of the striker face conforms to that of the impact face (43) of the projectile (4); that is, for example, the two are parallel. The transmitted impact energy is uniformly distributed over the impact face of the projectile (4), which advantageously reduces wear of the striker face ( 33) and impact face (43). | 3 |
This application is a continuation of Ser. No. 09/126,652 filed Jul. 31, 1998.
BACKGROUND OF THE INVENTION
This invention relates generally to automatic belay apparatus and its use; and more particularly it concerns the provision of safe, easily used, simple and compact, fall protection/lowering apparatus which can be employed in many situations to save lives and also for recreational purposes.
There is a known phenomenon that when a rope is wrapped around a fixed cylinder an X tension is applied to one end of the rope, a reactive force less than X (we will call Y) will stop the rope from slipping. More wraps around the cylinder will reduce the required Y force necessary for equilibrium.
Once equilibrium is attained between X and Y, reducing Y force by some A amount will allow the rope to slip. The amount of reduction in Y is dependent upon, among other things, the elasticity of the rope, the number of wraps around the cylinder, the diameter of the cylinder, and the co-efficient of friction between the rope and the cylinder.
To belay in nautical terms, is to “make fast (a rope) by winding on a cleat or pin”.
If one is climbing, to be belayed is to be protected (by a rope) from falling. This is accomplished by wrapping a rope around the belayer, or some other object, so as to reduce the Y tension when a climber falls, creating X tension. The governing equation depicting this phenomenon is:
X tension =θ a FY tension
Where θ a =Number of degrees, in radians, that the rope is in contact with a fixed cylinder
F=Coefficient of friction between the rope and the cylinder
a=Rope coefficient
Therefore, the greater number of wraps (radians), the lower Y is required for equilibrium.
And here is the paradox. If one wished Y to be minimal, multiple wraps are required; but, if one wishes to take up slack on the X rope when climbing by taking up Y tension, the weight of the rope X will be multiplied by the same factor (but in reverse) as when the climber falls which might make it impossible to take up slack, and hence a non-functional device. As one example:
For a wire rope, with 5½ wraps around a 3″ pipe (3.5 O.D.),
X=50# and Y=0.12#
Therefore, the amplification factor is 50#/0.12=400# Now, remove the 49# weight leaving a 1# rope and try to pull Y. Y=1#×400=400# to take up slack. This is not possible, or practicable.
Accordingly, there is need for improved apparatus to overcome the above problem so that slack can be automatically taken up while using the multiplying effect of multiple wraps; and there is need for apparatus which can be easily used for safe lowering of weights, as from great heights.
SUMMARY OF THE INVENTION
It is a major object of this invention to provide improved fall protection/lowering apparatus and methods, meeting the above needs. Basically, the apparatus of the invention is used for controlling vertical movement of a first weight (as for example a human being or other load), and comprises:
a) a first rotor rotatable in one direction about an axis and blocked against rotation in the opposite rotary direction,
b) a second rotor which is substantially freely rotatable in opposite rotary directions,
c) a control weight,
d) and lines supporting the first weight and control weight by the rotors, and including a first line wrapping about the first rotor and a second line entraining the second rotor, whereby changes in force exertion on the control weight determine alternative existence of a first mode of operation wherein line slippage relative to the first rotor allows the first weight to descend, and a second mode of operation wherein line non-slippage relative to the first rotor thereby blocks descending of the first weight.
Typically, the first line that wraps about the first rotor has line portions that extend downwardly to support loading imposed by the first weight and control weight, respectively; and the second line that entrains the second rotor also has line portions that extend downwardly to support loading imposed by the first weight and control weight respectively.
Another object is to provide the first rotor with an extended surface to engage multiple, non-interfering wraps of the first line. In this regard, the second rotor may typically comprise a pulley.
A further object is to provide the first rotor with two axially spaced generally conical portions, and a generally cylindrical portion intermediate those conical portions. Typically, the conical portions may have wrap engaging angularities characterized as maintaining the first line wraps free of sidewise interengagement or interference during operation of the apparatus to lower the first weight.
Accordingly, optimum operability and functioning of the first line and first rotor are maintained.
Yet another object is to provide the first rotor with an axial through passage, the second line passing through that passage, whereby a high degree of compactness of the equipment is achieved.
An additional object is to provide support structure for a human being who imposes the first weight in order to be lowered, such support structure defined by an upright strut connected to the line wrapped about the first rotor, and a seating ledge connected to the strut. That ledge may advantageously include at least one folding section having an up-folded position extending generally parallel to the upright stem, and a down-folded position extending generally laterally to seat the human being.
In use, the first rotor, i.e. a cylinder for example, is allowed to rotate freely in one direction (while taking up slack), and prevented from rotating in the opposite direction while resisting a fall. The taking up of slack is accomplished by hanging a weight on the Y reactive side of the cylinder greater than the weight of the rope on the X tension side of the cylinder; hence, in the above one example, Y need only be 1# to take up slack but it is strong enough to resist a 400# load during a fall.
If the device is to be used by a climber, once the climber has climbed he must be able to lower himself. This can be accomplished by attaching a separate control rope to the Y reactive weight, running this control rope over a freely rotating sheave, and then attaching the control rope to the X load. By shortening the control rope, the Y reactive force will be reduced until slippage occurs. Since X and Y will remain the same distance apart during slippage, slippage will continue unabated until the control rope is allowed to lengthen, for example lifted.
These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following specification and drawings, in which:
DRAWING DESCRIPTION
FIG. 1 is a perspective view of apparatus incorporating the invention;
FIG. 2 is an elevation showing modified apparatus incorporating the invention; and
FIG. 3 shows a folding seat type support for a human who may wish to climb onto the seat as from a building window, and lower himself, safely, from a height, at the outer side of a building, using the apparatus as described; and
FIG. 4 is a view like FIG. 2, but showing further modified apparatus, which is preferred.
DETAILED DESCRIPTION
In FIG. 1, a first load bearing rotor 10 such as a cylinder, is rotatable in one direction (clockwise, for example) but is blocked against rotation in the opposite rotary direction (counter-clockwise, as shown). Suitable bearing supports are shown at 11 and 12 , to support the axle 13 supporting the rotor, and extending in the axial direction indicated at 14 . A device to block counter-clockwise rotation may take the form of a ratchet arm 15 engaging ratchet teeth on the rotor. A suitable frame 19 supports 11 , 12 and 15 . Frame 19 may for example be attached to the outer side of a building.
A second rotor 16 , such as a sheave or pulley, is supported to be freely rotatable in opposite directions about an axis. In the example, the rotor 16 may be carried by axle 13 to be freely rotatable about axis 14 .
Two weights are supported by the two rotors. These include a first weight 20 and a control or reaction weight 21 , the weights in this example hanging from the rotors, as via supporting lines. These include a first line 22 supporting first weight 20 and wrapping about the rotor at wrap locations 22 a at which each turn of the wrap engages the rotor surface, line 22 then extending downwardly at 22 b to assist in supporting the control weight 21 . The lines also include a second line 23 extending downwardly toward the first weight 20 , and also extraining the sheave at location 23 a ; line 23 then extends downwardly at 23 b to assist in supporting the control weight 21 .
Changes in force exertion determine alternative existence of a first mode of operation wherein line slippage relative to the first rotor allows the first weight to descend, and a second mode of operation wherein line non-slippage relative to the first rotor thereby blocks descending of the first weight.
By “shortening” the line 23 (for example by manually lifting line 23 b ) reactive force is reduced, until slippage of line 22 occurs at the wrap locations 22 a , and slippage will continue, accompanied by lowering of first weight 20 , until line 23 b is allowed to “lengthen”, i.e. eliminating or reducing manual lifting of line 23 . Note that lines 22 and 23 , near the weight 20 , travel downwardly together during such slippage. Slippage at the wrap locations is prevented by friction, when the line 23 is “lengthened”.
Table A below indicates that, depending upon the type of line (such as rope) and, the amount of weight “removed” as by lifting line 23 b to allow slippage is affected by the number of wraps. (These results are results obtained for a selected set of rotors.)
TABLE A
Auto-Belayer Test
Wraps
Material
X
Y
{circumflex over ( )}
T
Wraps = 5 ½
Wire Rope
50
.12
.12
1.31 sec.
Sisal
50
.36
.24
4.37 sec.
Nylon
50
.98
.48
9.50 sec.
Wraps = 4 ½
Wire Rope
50
.96
.48
.90 sec.
Sisal
50
.96
.24
3.00 sec.
Nylon
50
1.20
.24
1.38 sec.
Wraps = 3 ½
Wire Rope
50
1.44
.48
.40 sec.
Sisal
50
2.28
.84
1.55 sec.
Nylon
50
3.41
.48
.38 sec.
Wraps = 2 ½
Wire Rope
50
4.18
1.5
Fast
Sisal
50
6.0
2.3
Fast
Nylon
50
7.11
.50
Fast
Wraps = 1 ½
Wire Rope
50
13.82
5.00
Fast
Sisal
50
11.8
3.5
Fast
Nylon
50
16.22
2.00
Fast
Wraps = ½
Wire Rope
50
33.13
7.00
Fast
Sisal
50
22.09
3.5
Fast
Nylon
50
33.51
3.00
Fast
Wraps = 5 ½
Nylon
50
.48
.48
very slow movement
Wraps = 4 ½
Nylon
50
1.20
.24
very slow movement
Nylon
50
1.20
1.08
5 seconds per foot
Nylon
50
1.20
1.20
1 second per foot
3.5″ Steel Shaft
{fraction (3/32)}″ Wire Rope (1000 lb. cap.) weighing 0.015 lbs per foot.
¼″ Twisted Sisal Rope (45 lb. Working load Limit) weighing 0.015 lbs. per foot.
¼″ Twisted Nylon Rope (124 lb. Working Load Limit) weighing 0.012 lbs. per foot.
X = 50 lb. load.
Y = Weight to just Balance Load.
{circumflex over ( )} = Amount of Weight removed from Y to allow slippage.
Wraps = Number of times the Material is around the Steel Shaft.
T = Time to fall 20″ when Y made 0.0 lbs.
The following are four important features:
1. Increasing wraps around a cylinder will non-linearly increase the force amplification until it eventually reaches an asymptotic limit.
2. To take up slack, the cylinder must rotate in one direction while, acting as a force amplifier, it cannot be allowed to rotate in the opposite direction.
3. The type of rope combined with the number of wraps affects the lowering sensitivity.
4. A deadweight in series with the device on the Y reactive side can act to both protect the climber from a fall and control the rate of his descent.
Referring now to FIG. 2, showing modified and preferred apparatus 100 , it includes a modified first rotor 110 about which a cable or line 111 is wrapped via multiple turns, at 111 a . Line 111 extends downwardly to support a first weight 112 and may be operatively connected to the weight. The rotor 110 is shown as rotatable about a horizontal axis 113 . The rotor has a through bore 110 a through which a cylindrical duct 114 extends. The duct projects at opposite ends of the rotor and which may be supported by bearings 115 and 116 to allow free rotation of the rotor and duct about axis 113 . Those bearings are carried by fixed walls 115 a and 116 a.
The opposite end extent 111 b of line or cable 111 extends downwardly to a freely hanging control weight 120 . The line 111 b is shown as turned by pulleys or idlers 117 and 118 , as shown, whereby control weight 120 may be located remotely from the weight 112 . Fixed structure 117 a and 118 a supports the idlers.
A second rotor or rotors 121 is or are shown, as at the end or ends of the duct 114 . A second cable or line 123 entrains the rotor or rotors 121 . One end portion 123 a of line 123 extends to control weight 120 , and is turned via idlers 124 and 125 as shown. The opposite end portion 123 b of the line 123 extends downwardly toward weight 112 . Since the line 123 slidably extends through the interior 114 b of the duct 114 , and therefore through windings 111 a , a very compact and simple assembly is provided, with lines 111 and 123 b extending close to one another and almost directly downwardly toward the weight 112 ; also line extents 123 a and 111 b may extend close together toward the remotely located control weight, and within a protective duct 140 , to shield lines 111 and 123 b from the weather.
Raising or lowering of the line extent 123 b , as via a control sleeve 126 extending about line 111 in proximity to weight 112 , controls the rate of descent of the weight 112 , as via control of control weight application to line extent 111 b . Such control variations control the friction forces exerted by the multiple wraps at 111 a on the surface of the rotor 110 , which in turn controls the slippage rate. A ratchet is indicated at 160 , for preventing reverse rotation of the rotor 110 .
For enhanced control of such slippage, the first rotor 110 may be provided with two axially spaced generally conical surface portions 110 b and 110 c , and a generally cylindrical surface portion 110 d intermediate the conical portions. The conical portions are interrupted by short cylindrical lands shown at 110 e and 110 f . It is found that such configurations serve to maintain the multiple wraps axially separated sufficiently as to avoid development of side-by-side rubbing of the multiple wraps. Such rubbing would otherwise interfere with accurate control of slippage of the wraps on the rotor. A means may be provided to urge line 111 leftwardly, to additionally assist in keeping the turns from side-by-side rubbing. Such means may comprise an idler 130 urged leftwardly as by a spring 131 . Raising of weight 112 is associated with take-up of slack in line 123 b , the importance of which is explained later, especially for safe climbing purposes.
A support may be provided for the weight 112 referred to, that support connected to at least one of the first and second lines. FIG. 3 shows the support in the form of a ledge 140 to seat a weight such as a human being. An upright strut 141 is connected to the ledge, and line 111 is shown connected to the strut. Ledge 140 is shown as including left and right sections 140 a and 140 b pivoted to the strut at 142 , as by hinges. Accordingly, the seating sections 140 a and 140 b may be swung down to the section position 140 b shown at such time as a human is to step onto the support to controllably and safely descend from a height, as at the outer side of a building, to escape from fire.
The rotors 121 may be non-rotary guides for line 123 ; and the bore of tube 114 may also or alternatively act as a line guide.
In the preferred apparatus of FIG. 4, the elements that remain the same as those in FIG. 2 carry the same identifying numerals. The rotor 210 (like rotor 110 ) has annular flanges 215 and 216 at its opposite ends, and which are received in annular grooves 215 a and 216 b in the fixed walls 217 and 218 of the frame 219 . Those flanges or tongues rotate in the grooves about axis 113 as the rotor rotates, with loading transferred from rotor 210 to walls 217 and 218 via annular bearing surfaces provided at 215 and 215 a , and at 216 and 216 a . Surfaces 110 b , 110 c , 110 d and 110 e are the same as in FIG. 2, as are the line 111 , wrappings at 111 a , and line extent 111 b.
Duct 214 is non-rotatable, and has its opposite ends clamped, via nuts 221 and 222 to the fixed walls 217 and 218 . Those nuts have screw threaded attachment at 221 a and 222 a to the duct. Duct 214 serves as a guide or guide duct for the line 223 passing through the duct, i.e. through windings 111 a . The opposite end interior surfaces 214 a and 214 b are flared or turned, as shown, to act as slide guides for the line 223 , to turn that line as shown, thereby eliminating need for the pulleys 121 as seen in FIG. 2 . See also fixed, non rotary guides for the lines, at 224 , 227 , 228 , and 225 .
Protective duct 240 shields lines 123 b and 111 b from the weather. Pulleys 240 and 241 are carried by the control weight 220 , to turn lines 123 a and 111 b , as shown, the ends of those lines being attached to 240 . Therefore, weight 120 need only travel one half the vertical distance at it travels in FIG. 2, as weight 112 is lowered; and as it is raised. Raising of weight 112 is associated with lowering of control weight 120 , which serves to take up slack in control line portions 123 , 123 a and 123 b . This is important for example where the weight 112 is a human climber, climbing a wall or rock face, whereby he may use non-slack line 123 b to control or stop a fall, immediately. | Apparatus for use in controlling vertical movement of a first weight, comprises a first element rotatable in one direction about an axis and blocked against rotation in the opposite rotary direction; a second element acting as a guide; a control weight; and lines supporting the first weight and control weight by the elements, and including a first line wrapping about the first element and a second line entraining the second element, whereby changes in force exertion on the control weight determine alternative existence of a first mode of operation wherein line slippage relative to the first element allows the first weight to descend, and a second mode of operation wherein line non-slippage relative to the first element thereby blocks descending of the first weight. In addition, the control weight is usable to exert force acting to remove slack from the second line, which is important for safety reasons, where the apparatus is used for climbing. | 0 |
This application is a continuation of application Ser. No. 568,953, filed Jan. 6, 1984, now abandoned, which is a continuation of application Ser. No. 368,778, filed Apr. 15, 1983, now abandoned.
TECHNICAL FIELD
The present invention relates to thrust bearings, and more particularly to pivoted shoe thrust bearings having optimally curved one-dimensional profiles.
BACKGROUND ART
Pivoted shoe thrust bearings have long been used in high speed applications or where low friction losses and low wear rates are essential. An example of such a bearing is the Kingsbury thrust bearing, or Michell bearing in Europe, where the bearing members are pivotable shoes which rest on hard steel pivots in a bearing housing. The shoes are free to automatically form a wedge-shaped oil film between the shoe surface and the moving thrust collar. The thrust collar transmits the thrust force through the hydrodynamic oil film to the pivoted shoes. In the prior art bearing, a base ring supports the shoes and equalizes the shoe loading. A housing is provided to contain and support the internal bearing elements. A shoe cage restrains the shoes against movement with the thrust collar, but not against outward displacement. The thrust load of the bearing is finally transmitted to a machine frame connected to the housing.
The conventional pivoted shoe thrust bearing also includes a lubricating system which continuously supplies the thrust collar and shoes with lubricating oil. In some applications, a cooling system is provided to reduce the temperature rise in the bearing.
Prior art pivoted shoes have had a flat surface on one side and a pivoting mechanism on the other side. One such pivoting mechanism in the prior art is the convex surface with an offset center of radius of curvature which provides line contact with a supporting surface. Another prior art method of pivoting is the point contact system, where the shoe has a hardened insert in the back which allows the shoe to pivot slightly. If the location of the pivot coincides with the geometrical center of the shoe, it becomes a centrally pivoted thrust bearing. Centrally pivoted bearings are useful in marine and other applications where reversibility is required.
The pivoted shoe in its pivoted position creates a tapered oil film between the shoe and the thrust collar. The oil film provides hydrodynamic pressure and load carrying capacity. The maximum load carrying capacity of the bearing is dependent on the inclination of the shoe and the location of the pivot point on the back of the shoe. The inclination of the shoe is usually designated by the symbol α, which represents the ratio of the maximum film thickness h 1 to a minimum film thickness h 0 .
Earlier investigations on fixed, as opposed to pivoted, shoe bearings [References 1-4] provided optimum values of α required for maximum load carrying capacity for a few oil film shapes such as taper, step, exponential and polynomial by solving a one dimensional Reynolds equation. The conclusions drawn on the basis of one dimensional analysis [Reference 3] underestimated the importance of film shape effect on the performance characteristics of fixed shoe bearings. The design variable α for a fixed shoe bearing is not of much practical value for a practicing engineer in industry as it is a function of minimum film thickness, which is controlled by the load. Therefore, fixed shoe bearings cannot be designed for these optimum values of α, unless the load is strictly fixed, and this limits the applications of such a design.
To overcome this problem, the pivoted shoe bearing, with a flat surface, became the subject of basic developments in hydrodynamic lubrication of bearings. In the case of pivoted shoe bearings, the maximum to minimum film thickness ratio α, is controlled by the location of pivot position and is independent of the minimum film thickness. This feature of a pivoted shoe bearing is the basic cause of its increasing popularity in the field of thrust and even journal bearings.
One dimensional flow solutions were modified by using correction factors to account for the effect of side leakage in finite bearings [References 5-7]. These correction factors were determined experimentally [References 5, 6]. Computer-aided finite difference solutions of a two dimensional Reynolds equation provided performance charts to analyze pivoted shoe bearings with flat surfaces [References 8-11]. The load carrying capacity of pivoted shoe thrust bearings has also been studied with reference to a few convex surface profiles [References 12-14].
Optimum solutions to many physical problems, such as the optimum path of a particle in motion, the optimum profile for sound traveling through horns [Reference 15], and the optimum shape profile for concentrators used in ultrasonic machining [Reference 16], have yielded cycloidal and catenoidal surface profiles. Although excellent performance based on one dimensional flow analysis of discontinuous oil film shape caused by a step profile provided enough incentive to researchers for the extension of related research in the past [Referrences 17-21], the present invention is directed towards one dimensional continuous surface profiles.
Exact solutions are known to the Reynolds equation for two dimensional flow for continuous fluid film shapes with simple functions only [References 7, 22-25] and fail to demonstrate the fact that optimum α values required for the maximum load carrying capacity have different values for infinitely wide and/or narrow bearings. Historically, the first computer method of solving bearing problems was Kingsbury's electrolytic tank method [Reference 26]. A mechanical differential analyzer has also been employed in an attempt to include the actual temperature distribution in the oil film [Reference 27]. The inadequacy of the solutions obtained by these methods has led to finite difference methods.
Various relaxation schemes have been used to accomplish numerical solutions for hydrodynamic thrust bearings by Archibald [Reference 17] and Christopherson [Reference 27] and for the stepped thrust bearings by Kettleborough [Reference 18]. An improved method by using matrix subroutines instead of relaxation schemes for the numerical solution of the general incompressible fluid film lubrication problem was presented by Castelli and Shapiro [Reference 28].
The solution of the Reynolds equation for imcompressible fluids has been obtained by the formulation of coefficient matrices and then using inversion subroutines [References 4, 29]. The use of new methods [Reference 30] to find nodal pressure without inverting any matrix is also known.
In recent years, several papers have been published using finite element methods for solving the Reynolds equation for different types of bearings [References 19-21, 31-34]. Other than complexities involved in the formulations of the two methods, namely finite difference and finite element techniques, two major factors always have to be considered. These are accuracy of the results and computer time involved. The use of variable dx and dz for different nodes by using higher order finite difference forms and new computer aided finite difference design schemes enlarge the scope of possible applications of finite difference method.
Load carrying capacity for centrally pivoted shoe bearings in practice has puzzled persons skilled in the art for many years, and explanations such as variable viscosity, variable density, viscosity changing with pressure and momentum effect at inlet were among the most usually offered theories [Reference 35-38]. Realizing the importance of surface profile, Raimondi and Boyd in their work [Reference 37] assumed an existence of a convex surface profile caused by manufacturing operations, temperature rise and operating load, and emphasized this as the most important factor accounting for the observed load carrying capacity of centrally pivoted shoes.
Raimondi and Boyd [Reference 37] and Abramovitz [Reference 12] both independently explained the working of the centrally pivoted bearing by assuming a convex surface profile and therefore an existence of a converging, diverging film shape in which the inactive diverging portion of the fluid film is utilized in switching the resultant pressure toward the center of the shoe length.
PRIOR ART REFERENCES
1 Load Rayleigh, "Notes on the Theory of Lubrication", Philosophical Magazine and Journal of Sciences, Vol. 53, 1918, pp. 1-12.
2 Martin H. M., "Theory of Michell Thrust Bearing", Engineering, Vol. 100, 1915, pp. 101-103, 154-155, 196-197, 207-208; Vol. 109, 1920, pp. 233-236, 338; Vol. 116, 1923, pp. 157, 203.
3 Fuller D. D., Theory and Practice of Lubrication for Engineers, Wiley, New York, 1956.
4 Pinkus, O., and Sternlicht, B., Theory of Hydrodynamic Lubrication, McGraw-Hill, New York, 1961.
5 Needs, S. J., "Effects of Side Leakage in 120 Degree Centrally Supported Journal Bearings", Trans. ASME, Vol. 56, 1934, pp. 209-219.
6 Needs, S. J., "Boundary Film Investigations", Trans. ASME, Vol. 62, 1940, pp. 331∝345.
7 Muskat, M. R., Morgan, F., and Meres, M. W., "The Lubrication of Sliders of Finite Width", Journal Applied Physics, Vol. 2, 1940, pp. 209-219.
8 Raimondi, A. A. and Boyd, J., "Applying Bearing Theory to the Analysis and Design of Shoe-Type Bearings", Trans. ASME, Vol. 77, No. 3, April, 1955, pp. 287-309.
9 Connor, J. J. (Editor-in Chief), and Boyd, J. (Technical Consultant), Standard Handbook of Lubrication Engineering, McGraw-Hill, New York, 1968.
10 Bosma, R., and Moes, H., "Design Charts for Optimum Bearing Configurations: 2 the Pivoted Shoe Thrust Bearings", ASME, Journal of Lubrication Technology, Vol. 92, 1970, pp. 572-577.
11 Kunin, I. A., "On the Hydrodynamic Theory of Lubrication of Shoe-Type Bearings", Translated from Original published in Russian; Akad, Nauk S.S.S.R., Issue 4-5, 1957, pp. 128-137.
12 Abramovitz, S., "Theory for a Slider Bearing with a Convex Shoe Surface; Side Flow Neglected", Franklin Institute Journal, Vol. 259, 1955, pp. 221-33.
13 Raimondi, A. A., and Boyd, J., "The Influence of Surface Profile on the Load Capacity of Thrust Bearings with Centrally Pivoted Shoes, Trans. ASME, Vol. 77, 1955, pp. 321-328; discussion, pp. 329-330.
14 Raimondi, A. A., "The Influence of Longitudinal and Transverse Profile on the Load Capacity of Pivoted Shoe Bearings", ASLE Trans., Vol. 3, No. 2, 1960, pp. 265-276.
15 Kinsler, L. E., and Fray, A. R., "Fundamentals of Acoustics, Willey, New York, 1962.
16 Singh, A. P., "Performance of Concentrators in Ultrasonic Machining", A dissertation submitted to the University of Manchester, England, (U.K.), for the degree of M.Sc., October 1976.
17 Archibald, F. R., "A Simple Hydrodynamic Thrust Bearing", Trans. ASME, Vol. 72, 1950, pp. 393-400.
18 Kettleborough, C. F., "The Stepped Thrust Bearing--A Solution by Relaxation Methods", ASME Trans., Journal of Applied Mechanics, Vol. 76, 1954, pp. 19-24.
19 Rhode, S. M., "Finite Element Optimization of Finite Stepped Slider Bearing Profiles", Trans. ASLE, Vol. 17, No. 2, 1974, pp. 105-110.
20 Maday, C. J., "The One-Dimensional Optimum Hydrodynamic Gas Slider Bearing", Journal of Lubrication of Technology, Trans. ASME, Series F, Vol. 90, No. 1, January 1968, pp. 281-284.
21 McAllister, G. T., Rohde, S. M., and McAllister, M. N., "A Note on the Optimum Design of Slider Bearings", Journal of Lubrication Technology, Trans. ASME, Series F, Vol. 102, No. 1, January 1980, pp. 117-119.
22 Charnes, A., and Saibel, E., "On the Solution of the Reynolds Equation for Slider Bearing Lubrication-Part 1", Trans. ASME, Vol. 74, 1952, pp. 867-873; Part II, Vol. 77, 1955, pp. 269-272; Parts-VI, VII, IX (with Osterle, F.), Vol. 75, 1953, pp. 1133-1136, Vol. 76, 1954, pp. 327-330, vol. 77, 1955, pp. 1185-1187.
23 Boegli, C. P., "Hydrodynamic Lubrication of Finite Slider", Journal of Applied Physics, Vol. 18, 1947. pp. 482-488.
24 Wood, W. L., "Note on a New Form of the Solution of Reynolds' Equation for Michell Rectangular and Sector-Shaped Shoes", Philosophical Magazine, Series 7, Vol. 40, 1949, pp. 220-26.
25 Michell, A. G. M., "The Lubrication of Plane Slider", Zeitschrift Fur Mathematik und physik, Vol. 52, 1905, pp. 123-137.
26 Kingsbury, A., "On Problems in the Theory of Fluid Film Lubrication with an Experimental Method of Solution", Trans. ASME, Vol. 53, 931, pp. 59-75.
27 Christopherson, D. G., "A New Mathmatical Method for the Solution of Film Lubrication Problems", Proceedings of the Institution of Mechanical Engineers, Vol. 146, 1947, pp. 126-135.
28 Castelli, V., and Shipiro, W., "Improved Method for Numerical Solution of the General Incompressible Fluid Film Lubrication Problem", ASME Journal of Lubrication Technology, Vol. 89, April 1967, pp. 211-218.
29 Singh, A. P., "Optimum Design of Hydrodynamic Slider Bearings of Different Film Shapes", Design Report, Department of Mechanical Engineering, Tennessee Technological University, Cookeville, TN, U.S.A., August, 1980.
30 Carnahan, B., Luther, H.A., and Wilkes, J. O., Applied Numerical Methods, Willey, New York, 1969.
31 Reddi, M. M. "Finite Element Solution of the Incompressible Lubrication Problem", ASME Journal of Lubrication Technology, Vol. 91, 1969, pp. 524.
32 Wada, S., Hayashi, S., and Migita, "Application of Finite Element Method to Hydrodynamic Lubrication Problems-Part 1: Infinite Width Bearings", Bulletin of JSME, Vol. 14, 1971, pp. 1234.
33 Booker, J. F., and Huebner, K. H., "Application of Finite Element Methods to Lubrication; An Engineering Approach", ASME Journal of Lubrication Technology, Vol. 94, 1972, pp. 313-323.
34 Allaire, P. E., Nicholas, J. C., and Gunter, E. J., Jr., "Systems of Finite Elements for Finite Bearings", Journal of Lubrication Technology, Trans. ASME, Series F, Vol. 99, No. 2, April 1977, pp. 187-197.
35 Shaw, M. C., "An Analysis of the Parallel-Surface Thrust Bearing", Trans. ASME, Vol. 69, 1947, p. 387.
36 Cope W. F., "The Hydrodynamical Theory of Film Lubrication", Proceedings of the Royal Society of London, England, Series A, Vol. 197, 1949, p. 201.
37 Raimondi, A. A. and Boyd, J., "The Influence of Surface Profile on the Load Capacity of Thrust Bearings With Centrally Pivoted Shoes", Trans. ASME, Vol. 77, 1955, pp. 321-328, discussion, pp. 329-330.
38 Raimondi, A. A., "The Influence of Longitudinal and Transverse Profile on the Load Capacity of Pivoted Shoe Bearings", ASLE Trans., Vol. 3, October 1960, pp. 265-276.
39 Pinkus, O. and Sternlicht, B., Theory of Hydrodynamic Lubrication, McGraw Hill, New York, 1961.
40 Conor, J. J. (Editor-In-Chief) and Boyd, J. (Technical Consultant), Standard Handbook of Lubrication Engineering, McGraw Hill Book Co., New York, 1968. CL SUMMARY OF THE INVENTION
The present invention provides an improved pivoted shoe bearing including a shoe which has a mathmatically defined surface profile. In a preferred embodiment, rectangular shoes have a surface machined thereon in accordance with a mathematical relationship optimized as to load carrying capacity. The mathematically defined profile, which is defined by an optimum value of α, is specific to the width and length of the shoe. In an alternate embodiment of the invention, a quadratic profile is machined upon a shoe in a centrally pivoted shoe bearing.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete understanding of the invention and its advantages will be apparent from the following description taken in conjunction with the accompanying drawings in which:
FIG. 1 is a partially broken away side view of a pivoted shoe bearing constructed in accordance with the present invention; and
FIG. 2 is an enlarged, schematic view of a shoe constructed in accordance with the present invention;
FIG. 3 is a view of the shoe of FIG. 2 rotated 90°;
FIG. 4 is a comparison chart of proposed surface profiles for hydrodynamically lubricated pivoted square shoes at their optimum inclinations;
FIG. 5 is a chart of the optimum values of performance coeffecients for a pivoted shoe bearing having a conventional flat face surface;
FIG. 6 is a chart of the optimum values of performance coefficients for a pivoted shoe bearing having an exponential surface profile;
FIG. 7 is a chart of the optimum values of performance coefficients for a pivoted shoe bearing having a catenoidal surface profile;
FIG. 8 is a chart of the optimum values of performance coefficients for a pivoted shoe bearing having a cycloidal surface profile;
FIG. 9 is a chart of the optimum values of performance coefficients for a pivoted shoe bearing having a truncated cycloidal surface profile;
FIG. 10 is a chart of the optimum values of performance coefficients for a pivoted shoe bearing having a parabolic surface profile;
FIG. 11 is a chart of the optimum values of performance coefficients for a pivoted shoe bearing having a cubic surface profile;
FIG. 12 is a chart of the optimum values of performance coefficients for a pivoted shoe bearing having a quadratic surface profile; and
FIG. 13 is a chart of the optimum performance coefficients for a centrally pivoted shoe bearing having a quadratic surface profile.
DETAILED DESCRIPTION
Referring initially to FIG. 1, bearing 10 is associated with machine frame 12. Thrust collar 14 is disposed to translate relative motion of machine frame 12 in the direction of arrow 16. A plurality of shoes 18 are pivotally restrained at pivots 19 by leveling plates 20, which span between inverted leveling plates 22. Leveling plates 20 and inverted leveling plated 22 serve to equalize the thrust transmitted by thrust collar 14 to shoes 18. Each shoe 18 includes a Babbitt lining 24. Babbitt linings 24 are machined to form surface 26 adjacent thrust collar 14. Lubricant 28 fills the voids between machine base 12 and thrust collar 14.
The thrust load imposed on thrust collar 14 is supported by the total number of shoes 18 in bearing 10. Shoes 18 are supported by pivots 19, such that when thrust collar 14 translates in the direction of arrow 16, shoes 18 pivot in a direction opposite to arrow 16.
The translation of thrust collar 14 in the direction of arrow 16 generates a hydrodynamic fluid film of lubricant 28 over shoes 18 which supports the thrust load and separates thrust collar 14 from surfaces 26. The hydrodynamic fluid film is created by the viscous or shear forces acting in lubricant 28 parallel to the direction of relative movement between the thrust collar 14 and surfaces 26. The boundary layer adjacent thrust collar 14 pulls the layer of lubricant 28 immediately adjacent to thrust collar 14, and in this way a velocity gradient is established in the lubricant in the gap between thrust collar 14 and surfaces 26. The gap between thrust collar 14 and surfaces 26 is wedge-shaped, which causes the pressure of lubricant drawn 28 into the gap to increase towards the narrow end of the gap, and thus creates a pressurized cushion or fluid film which dynamically supports the thrust load. The shape of the fluid-wedge is determined by the profile of surface 26.
FIG. 2 is an enlarged, schematic view of a single shoe 18. The thickness of the gap between thrust collar 14, which is maintained by the lubricant film, is designated by the reference figure h 0 at the point of minimum film thickness and the reference figure h 1 at the point of maximum film thickness. Surface 26 is designated by the thickness t of Babbitt layer 24. Thickness t is a function of x, which is measured from leading edge 30 of shoe 18. Shoe 18 has a total length in the x direction of L x . Pivot 19 is located at a distance x from leading edge 30 of shoe 18.
Referring now to FIG. 3, shoe 18 has a total width of L z . Pivot 19 is located at a distance z from edge 32 of shoe 18. In practice, the distance z will be equal to half of L z .
Surface 26 may be obtained by machining a conventional flat surface shoe in such a manner that the thickness t of Babbitt layer 24 with respect to the x-axis for a particular shape is mathematically defined as follows:
(A) Exponential surface profile:
t=h.sub.0 [1.0+(α-1)(x/L.sub.x)-exp (ln α(x/L.sub.x))]
(B) Catenoidal surface profile:
t=h.sub.0 [1.0+(α-1)(x/L.sub.x)-COS H(COS H.sup.-1 α(x/L.sub.x))]
(C) Cycloidal surface profile:
t=h.sub.0 [(α-1) Sin (2πx/L.sub.x)]/(2π)
(D) Truncated cycloidal surface profile:
t=h.sub.0 [(α-1) Sin (πx/L.sub.x)]/π
(E) Polynomial surface profile:
t=h.sub.0 (α-1)[(x/L.sub.x)-(x/L.sub.x).sup.n ]
where n=2, 3 and 4 represents parabolic, cubic and quadratic surface profiles respectively. A comparative view of the different surface profiles for a square shoe at its optimum inclinations is shown in FIG. 4. Numerically controlled highly specialized tooling with the aid of unconventional machining processes can be used to obtain the precision required for the machining of these surface profiles.
A generalized computer program has been employed to solve the two dimensional Reynolds equation by using finite difference methods. A finite difference mesh was generated for the shoe geometry. In the analysis of continuous lubricant film shapes, variation in film thickness in both x and/or z directions was permitted. The program determined the pressure distribution in the lubricant for the specified minimum film thickness h 0 , the film thickness ratio α and the lubricant viscosity μ at the average lubricant temperature. The load-carrying capacity W, pivot location x, z, flow rates of lubricant through the gap (Q x , flow in the x direction, Q z , flow in the z direction, and Q T , total flow), coefficient of friction f, friction power loss and temperature rise ΔT relative to the lubricant inlet temperature were then determined. The analysis has been performed for several values of the film thickness ratio α in order to determine an optimum value of α with respect to a particular performance characteristic for a particular film shape.
The above information has been obtained collected for several film shapes including polynomial film shapes for different values of power factor n.
The numerical results from the computer analysis for α and nondimensional performance coefficients are shown below in Tables 1, 2, 3, 4, and 5 for L z /L x ratios of 4.0, 2.0, 1.0, 0.5, and 0.25 respectively. The nondimensional performance coefficients are: pivot location coefficients K x , K z ; load coefficient K p , flow coefficients K Q , K Qz ; flow ratio coefficient R Q , friction force coefficient K f , the coefficient of friction coefficient K c , and the temperature rise coefficient K T . These coefficients are defined as follows:
K.sub.x =x/L.sub.x =(0.5 for centrally pivoted shoe bearings) (1)
K.sub.z =z/L.sub.z =0.5 (due to symmetrical pressure distribution) (2)
K.sub.p =Wh.sub.0.sup.2 /μUL.sub.x.sup.2 L.sub.z (3)
K.sub.Q =Q.sub.T /Uh.sub.0 L.sub.z (4)
R.sub.Q =Q.sub.z /Q.sub.T (5)
K.sub.Qz =R.sub.Q K.sub.Q (6)
K.sub.f =E.sub.T h.sub.0 /μU.sup.2 L.sub.x L.sub.z (7)
K.sub.c =fL.sub.x /h.sub.0 (8)
and
K.sub.T =ΔTh.sub.0.sup.2 JγC/μUL.sub.x (9)
where U equals the velocity of thrust collar 14, W equals the maximum load carrying capacity shoe 18, μ equals the absolute velocity of lubricant 28, E T equals the total friction power loss due to flow in the x and z directions, ΔT equals T 2 -T 1 (T 2 and T 1 are the outlet and inlet temperatures respectively), J equals the mechanical equivalent of heat, γ equals the weight density of lubricant 28 and C equals the specific heat of lubricant 28.
TABLE 1__________________________________________________________________________Optimum Performance Coefficients for different surface profiles,L.sub.z /L.sub.x = 4.0SURFACEPROFILE α K.sub.x K.sub.p K.sub.Q R.sub.Q K.sub.f K.sub.c K.sub.T__________________________________________________________________________Flat 2.2 0.5735 0.13214 0.6750 0.0950 0.8980 6.7500 1.9628Exponential 2.3 0.5665 0.13818 0.6691 0.0955 0.9322 6.7050 2.0538Catenoidal 2.5 0.5452 0.15030 0.6454 0.0956 1.0314 6.8100 2.3383Cycloidal 2.0 0.5605 0.16134 0.6647 0.1007 1.0340 6.3600 2.3086Trunicated 2.5 0.5356 0.15075 0.6338 0.0976 1.0633 7.0050 2.4507CycloidalParabolic 2.5 0.5525 0.15196 0.6562 0.1004 1.0310 6.7350 2.3082Cubic 2.7 0.5265 0.14490 0.6629 0.0948 1.0692 7.335 2.4927Quadratic 2.9 0.5057 0.13370 0.6023 0.0890 1.0836 8.0700 2.5878__________________________________________________________________________
TABLE 2__________________________________________________________________________Optimum Performance Coefficients for different surface profiles,L.sub.z /L.sub.x = 2.0SURFACEPROFILE α K.sub.x K.sub.p K.sub.Q R.sub.Q K.sub.f K.sub.c K.sub.T__________________________________________________________________________Flat 2.2 0.5794 0.10947 0.7408 0.1881 0.8652 7.7852 1.7959Exponential 2.4 0.5727 0.11556 0.7465 0.1998 0.9027 7.6791 1.8661Catenoidal 2.6 0.5475 0.12756 0.7160 0.1999 1.0017 7.7428 2.1460Cycloidal 2.1 0.5683 0.13382 0.7433 0.2131 1.0018 7.3397 2.1024Truncated 2.6 0.5374 0.12852 0.7055 0.2042 1.0344 7.9337 2.2488CycloidalParabolic 2.6 0.5561 0.12858 0.7325 0.2092 0.9988 7.6367 2.1047Cubic 2.8 0.5232 0.12413 0.6838 0.1913 1.0394 8.2519 2.3044Quadratic 3.0 0.5034 0.11537 0.6652 0.1876 1.0602 9.1104 2.3998__________________________________________________________________________
TABLE 3__________________________________________________________________________Optimum Performance Coefficients for different surface profiles,L.sub.z/L.sub.x = 1.0SURFACEPROFILE α K.sub.x K.sub.p K.sub.Q R.sub.Q K.sub.f K.sub.c K.sub.T__________________________________________________________________________Flat 2.3 0.5963 0.6993 0.8853 0.3351 0.7971 11.10 1.4763Exponential 2.7 0.5897 0.07564 0.9401 0.3779 .83167 10.65 1.4830Catenoidal 3.0 0.5575 0.08664 0.9079 0.3898 0.9368 10.50 1.7352Cycloidal 2.2 0.5822 0.08593 0.8861 0.3703 0.9129 10.26 1.7259Truncated 2.9 0.5429 0.08817 0.8874 0.3891 0.9691 10.68 1.8345CycloidalParabolic 2.8 0.5629 0.08660 0.9046 0.3839 0.9244 10.35 1.7154Cubic 3.2 0.5307 0.08622 0.8666 0.3803 0.9825 11.10 1.8918Quadratic 3.5 0.5027 0.08150 0.8314 0.3670 1.0126 12.15 2.0096__________________________________________________________________________
TABLE 4__________________________________________________________________________Optimum Performance Coefficients for different surface profiles,L.sub.z /L.sub.x = 0.5SURFACEPROFILE α K.sub.x K.sub.p K.sub.Q R.sub.Q K.sub.f K.sub.c K.sub.T__________________________________________________________________________Flat 2.5 0.6285 0.02978 1.0457 0.4697 0.6925 22.6979 1.1530Exponential 3.2 0.6173 0.03326 1.2286 0.5507 0.7049 20.4918 1.0499Catenoidal 3.8 0.5750 0.03973 1.2978 0.5927 0.8024 19.4735 1.1610Cycloidal 2.6 0.6207 0.03761 1.1616 0.5437 0.7733 19.8129 1.2146Truncated 3.7 0.5602 0.04075 1.2988 0.6000 0.8336 19.6857 1.2101CycloidalParabolic 3.4 0.5852 0.03915 1.2490 0.5745 0.7865 19.3887 1.1695Cubic 4.2 0.5427 0.04079 1.3253 0.6100 0.8563 20.2372 1.2263Quadratic 4.8 0.5038 0.03974 1.3212 0.6140 0.9051 22.0191 1.3030__________________________________________________________________________
TABLE 5__________________________________________________________________________Optimum Performance Coefficients for different surface profiles,L.sub.z /L.sub.x = 0.25SURFACEPROFILE α K.sub.x K.sub.p K.sub.Q R.sub.Q K.sub.f K.sub.c K.sub.T__________________________________________________________________________Flat 2.8 0.6761 0.00977 1.2077 0.5564 0.6047 61.14 0.9138Exponential 4.1 0.6622 0.01099 1.6461 0.6764 0.5845 52.14 0.7039Catenoidal 5.6 0.6142 0.01298 2.0607 0.7513 0.6504 48.78 0.6606Cycloidal 3.6 0.6786 0.01234 1.6209 0.6840 0.6179 48.78 0.7596Truncated 5.3 0.5979 0.01323 2.0465 0.7525 0.6733 49.50 0.6891CycloidalParabolic 4.6 0.6319 0.01271 1.8158 0.7165 0.6366 48.90 0.7152Cubic 6.2 0.5749 0.01334 2.2198 0.7724 0.6946 50.64 0.6653Quadratic 7.3 0.5183 0.01327 2.3807 0.7891 0.7512 55.02 0.6796__________________________________________________________________________
Table 6 provides a comparative view of load carrying capacity performance coefficient K p of shoe 18 at its optimum inclination α for all the considered surface profiles for a range of L z /L x ratios. The performance of an infinitely wide bearing is also shown in Table 6 for comparison purposes. The net gain in load carrying capacity of using these profiles as compared to a conventional flat surface shoe is also shown in parentheses in the same table. The maximum gain in load carrying capacity for each L z /L x ratio is designated by an asterisk (*).
TABLE 6__________________________________________________________________________Load coefficient K.sub.p and the gain with respect to conventionalshoe for different values of L.sub.z /L.sub.x and optimum α forthe considered surface profiles.SURFACE L.sub.z /L.sub.xPROFILE 0.25 0.5 1.0 2.0 4.0 ∞__________________________________________________________________________Flat 0.00977 0.02978 0.6993 1.0947 0.13214 0.16025 (1.00) (1.00) (1.00) (1.00) (1.00) (1.00)Exponential 0.01099 0.03326 0.07564 0.11556 0.13818 0.16518 (1.1249) (1.1167) (1.0817) (1.0556) (1.0457) (1.0308)Catenoidal 0.01298 0.03973 0.08664 0.12756 0.15030 0.17500 (1.3286) (1.3340) (1.2390) (1.1653) (1.1374) (1.0920)Cycloidal 0.01234 0.03761 0.08593 0.13382 0.16134 0.1924 (1.2631) (1.2629) (1.2288) (1.2224)* (1.2210)* (1.2006)*Truncated 0.01323 0.04075 0.08817 0.12852 0.15075 0.1749Cycloidal (1.3542) (1.3683) (1.2608)* (1.1740) (1.1408) (1.0914)Parabolic 0.0127 0.03915 0.08660 0.12858 0.15196 0.1774 (1.3009) (1.3146) (1.2384) (1.1492) (1.1420) (1.1070)Cubic 0.01334 0.04079 0.08622 0.12413 0.14490 0.1672 (1.3654)* (1.3697)* (1.2330) (1.1339) (1.0966) (1.0434)Quadratic 0.01327 0.03974 0.08150 0.11537 0.13370 0.1532 (1.3582) (1.3345) (1.1655) (1.0539) (1.0118) (0.9560)__________________________________________________________________________
Several important characteristics of the various surface profiles should be noted from the results given in Tables 1 through 6:
(1) The value of optimum α increases as the L z /L x ratio of shoe 18 with any surface profile is reduced.
(2) The range of capacity in load carrying increases from 20% for an infinitely wide shoe having a cycloidal surface to a 37% gain for a narrow shoe with L z /L x ratio of 0.25 having a cubic (polynomial with n=3) surface demonstrates the importance of film shape effects.
(3) The dimensions of shoe 18, such as the L z /L x ratio, have a tremendous impact on the selection of the type of profile for surface 26 to be used while designing a pivoted shoe bearing. As observed in Table 6, the performance of the cycloidal surface 26 is excellent for wider shoes with a L z /L x ratios of 2 and more, whereas truncated cycloidal surfaces 26 offer better results than cycloidal surfaces 26 for narrow shoes with L z /L x equal to one or less than one. This fact is also demonstrated by polynomial surfaces 26 having different values of power factor n. The optimum value of power factor n required to provide maximum load carrying capacity changes from n=2 for wider shoes 18 to n=3 for narrow shoes 18.
(4) For a polynomial surface 26 with power factor n equal to 4.0, a quadratic surface, the location of pivot 19 which would provide the maximum load carrying capacity has been found to be very close to the center of the shoe 18. For L z /L x equal to 1.0, for example, the location of pivot 19 is found to be at 0.5027 of the length of shoe 18. Moreover, as observed in the tables for different L z /L x ratios and also in the case of infinitely wide shoes the pivot location is closer to the center in the case of quadratic surface profiles, and is not limited to a square shoe. This important feature of quadratic surface profiles provides an additional capability of reversibility of operation along with its improved load carrying capacity, because of the central location of pivot 19.
The optimum design charts in FIGS. 5-12 have been developed using results shown in Tables 1-5 for each particular profile of surface 26 for the maximum load carrying capacity. In pivoted shoe bearings, the value of α is controlled by the location of pivot 19 and becomes independent of h 0 , U or μ. There are six variables which can affect the load carrying capacity and other characteristics of a pivoted shoe bearing and are listed as h 0 , x (or α), L z , L x , U and μ. Once L z and L x are fixed, there is one value of pivot location x which provides an optimum value of film thickness ratio α for a particular film shape at which bearing 10 carries the maximum load. Viscosity and speed have a linear relationship with the load carrying capacity. Hence, the main objective is to find an optimum value of α and its corresponding pivot location for a given L z /L x ratio for a particular surface profile. The six non-dimensional performance coefficients K p , K Q , R Q , K f , K c , and K T are used as design variables which define the performance characteristics of an optimum bearing for a specific value of the L z /L x ratio, meanwhile defining the optimum value of the film thickness ratio α.
The selection of a particular surface profile depends upon the L z /L x ratio of the shoe and the required behavior of other performance characteristics such as flow rate, side flow, frictional power loss, coefficient of friction and temperature rise. The following two numerical examples illustrate the use of the design charts given in FIGS. 5 through 12.
EXAMPLE 1
A pivoted shoe bearing 10 is to have optimum performance characteristics, with L z /L x =0.5 in order to carry a load of 5000 lbf (22241N) and a minimum film thickness h 0 of 0.002 in. (0.0508 mm) for a thrust collar 14 velocity U of 1200 in/sec (30.48 m/sec). Lubricant 28 is medium turbine oil entering leading edge 30 of bearing at 120° F. (48.89° C.) has γ=0.035 lbf/in 3 (0.00626 Kg/Cm 3 ), C=0.5 BTU/lbf-°F. (2093 J/Kg-°C.), and constants K1 and K2 are -3.4560 and 23.8501 respectively. The kinematic viscosity ν of lubricant 28 in centistokes as a function of temperature T in °F. is given as
ν=exp [ exp (Kl ln (T+460)+K2]-0.6
The coefficient of viscosity ν of lubricant 28 in lbf-S/in 2 is given as
μ=νρ.sub.t 1.45×10.sup.-7
The density of lubricant 28 ρ t at temperature T is given as
ρ.sub.t =ρ.sub.60 /[1+β(T-60)]
where ρ 60 is the density of lubricant 28 at 60° F. temperature and β is the coefficient of expansion. The values of ρ 60 and β for lubricant 28 are 0.877 and 0.000437 respectively.
As observed in Table 6, for the given L z /L x ratio of 0.5, the cubic surface profile (polynomial with n=3) offers the maximum load carrying capacity. Hence, pivoted shoe bearing 10 having a cubic surface 26 profile will be designed, and then the performance with a conventional flat surface will be compared with the performance of the designed bearing 10.
Cubic Surface Profile
Using FIG. 11, for R t =L z /L x =0.5: α=4.2, K x =0.5427, Kp=0.04079, K Q =1.3253, R Q =0.6100, K f =0.8563, K c =20.2372, and K T =1.2263.
The coefficient of viscosity μ at inlet temperature 120° F. is calculated using the viscosity-temperature relationship and is equal to 4.5579×10 -6 lbf-S/in 2 . Substituting L z =R t L x in equation (3), ##EQU1##
Before accepting these dimensions the values of ΔT must be balanced such that the average film temperature, as determined from viscous losses, coincides with the temperature-viscosity property of the given lubricant. Thus, from equation (9), ##EQU2## and the average temperature is
T.sub.avg =148.9360° F.
At this temperature,
μ=2.5036×10.sup.-6 lbf-S/in.sup.2,
and
L.sub.x =6.8853 in. (17.4887 Cm)
ΔT=38.8149° F. (3.786° C.)
T.sub.avg =139.4074° F. (59.67° C.)
After six more iterations the final value of μ at average temperature 141.3766° F. is 2.8941×10 -6 lbf-S/in 2 .
From equations (1) through (9), we find
L x =6.5605 in. 916.6637 Cm)
L z =3.2808 in. (8.3318 Cm)
x=0.5427×6.5605=3.5604 in. (9.0434 Cm)
z=0.5×3.2802=1.6401 in. (4.1659 Cm)
Q T =10.4334 in 3 /sec (170.9728 Cm 3 /sec)
Q z =6.3644 in 3 /sec (104.2934 Cm 3 /sec)
friction horsepower=5.8179 horsepower (4338.3985 W)
f=0.00617
T=42.7533° F. (5.9741° C.)
Conventional Flat Surface Profile
Using FIG. 5 for R t =0.5, we have α=2.5, K x =0.6285, K p =0.02978, K Q =1.0457, R Q =0.4697, K f =0.6925, K c =22.6295, and K T =1.1530.
Repeating the heat balance loop for 12 iterations the final value of μ at average temperature 142.1084° F. is found to be 2.8528×10 -6 lbf-S/in 2 . Using equations (1) through (9) we find
L x =7.3208 in. (18.5948 Cm)
L z =3.6604 in. (9.2974 Cm)
x=4.6011 in. (11.6868 Cm)
z=1.8302 in. (4.6487 Cm)
Q T =9.1864 in 3 sec (150.5381 Cm 3 /sec)
Q z =4.3149 in 3 sec (70.7085 Cm 3 /sec)
friction horsepower=5.7752 horsepower (4306.57 W)
f=0.00618
ΔT=44.2167° F. (6.7871° C.)
It should be noted that for the desired load carrying capacity, the proposed design with new surface 26 requires a lesser shoe area 18 as compared to the conventional flat surface design, and thereby the size and space required for bearing 10 are reduced.
EXAMPLE 2
Pivoted shoe bearing 10 is to have a truncated cycloidal surface 26, whose dimensions are L x =6 in. (15.24 Cm) and L z =6 in. (15.24 Cm). For the same lubricant 28 as used in the previous example and a thrust collar 14 velocity of 500 in/sec (12.7 m/sec), bearing 10 has a load carrying capacity of 10,000 lbf (44482N).
To analyze this bearing 10, the minimum film thickness h 0 must be determined, balancing ΔT. For R t =6/6=1.0, from FIG. 9, we read the properties of this bearing 10 as: α=2.9, K x =0.5429, K p =0.08817, K Q =0.8874, R Q =0.3891, K f =0.9691, K c =10.6800 and K T =1.8345.
Using the viscosity-temperature relationship, μ 120 =4.5579×10 -6 lbf-S/in 2 .
Substituting the value of K p in equation (3), we have ##EQU3##
Before accepting these calculations, the value of ΔT must be balanced as discussed in the previous example. Thus, from equation (9) we find ##EQU4## and average temperature as
T avg =137.6928° F. (58.7182° C.).
At this temperature, μ=3.1146×10 -6 , and
h 0 =0.001722 inc. (0.04374 mm)
T=35.3754° F. (1.8752° C.)
T avg =137.6877° F. (58.7154° C.), which is close to the previous value. Hence, using equations (1 through 9), we find
x=3.2574 in. (8.2739 Cm)
z=3.0 in. (7.62 Cm)
Q T =4.5850 in 3 /sec (75.1347 Cm 3 /sec)
Q z =1.7840 in 3 /sec (29.2345 Cm 3 /sec)
friction horsepower=2.3890 horsepower (1781.4773 W)
f=0.0031
Repeating the same procedure using FIG. 5 for a conventional flat surface pivoted shoe, the minimum film thickness is found to be 0.00152 in. (0.0386 mm). This shows that the use of truncated cycloidal surface 26 instead of a conventional flat surface pivoted shoe improves the factor of safety by increasing minimum film thickness for the given operating load.
It is thus apparent that one dimensional continuous surface profiles have a significant effect on the load carrying capacity of both infinitely wide as well as finite pivoted shoe bearings. The selection of a particular surface profile depends upon the dimensions of the shoe. The performance of cycloidal profiles is optimal for wider bearings with L z /L x ratio of 2 and more, whereas truncated cycloidal profiles are optimal for narrow bearings with L z /L x ≦1.0. Similarly, the optimum polynomial surface profile changes from parabolic (n=2) for wider bearings to cubic (n=3) for narrow bearings. The quadratic surface profile, along with its improved load carrying capacity, also provides a pivot location near center, which is very useful in attaining reversibility of operation.
Centrally pivoted shoe bearings are commonly used in marine work and several other fields where it is required that the bearing be capable of rotating or translating in both directions. As noted above, the quadratic profile for surface 26 provides a pivot location near center in most instances. The performance coefficients K x and K p for certain values of α where K x is close to 0.5 are shown in Table 7 along with the results obtained from FIGS. 7 and 8 of Reference [12] for the centrally pivoted shoe bearing with convex surface profiles.
TABLE 7______________________________________Performance coefficient K.sub.p for an infinitely widecentrally pivoted shoe bearing with convex (Reference [12])and quadratic surface profiles.Convex Surface Profile [12] Quadratic Surface Profileh.sub.1 /h.sub.2 δ/h.sub.0 K.sub.p α K.sub.x K.sub.p______________________________________1.43 0.1 0.1239 2.4 0.495 0.15151.77 0.3 0.1512 2.5 0.499 0.15242.15 0.6 0.1314 2.6 0.501 0.15292.65 0.9 0.1162 2.7 0.504 0.15323.31 1.2 0.0984______________________________________
Comparison of results for these two different designs clearly indicate that the load carrying capacity of a quadratic surface profile is better than a convex surface profile even for the optimum crown height ratio δ/h O of Reference [12]. It should be noted that in view of fluctuating load conditions, it would be very difficult to maintain the optimum values of δ/h O in practice. Moreover, a quadratic continuous surface profile does not form any inactive film portions such as the converging-diverging films found in the case of convex surface profiles, and thus, use of a quadratic profile leads to an improved load carrying capacity.
The numerical results for nondimensional performance coefficients K p , K Q , R Q , K f , K c and K T for a few values of shoe inclination α have been calculated where the pivot location coefficient K x is close to 0.5. The results are shown in Table 8 for a wide range of L z /L x ratios from 0.25 for narrow bearings to 4.0 for wide bearings.
TABLE 8______________________________________Performance coefficients for different L.sub.z /L.sub.x ratios ofcentrally pivoted shoe bearing with quadratic surface profile.L.sub.z /L.sub.x α K.sub.x K.sub.p K.sub.Q R.sub.Q K.sub.f K.sub.c K.sub.T______________________________________ 0.25 6.1 0.496 0.01324 2.2095 0.7528 0.7695 56.70 0.7946 6.2 0.498 0.01324 2.0588 0.7563 0.7678 56.52 0.7836 6.3 0.500 0.01325 2.0881 0.7597 0.7662 56.34 0.7729 6.4 0.502 0.01325 2.1173 0.7630 0.7645 56.22 0.7625 6.5 0.504 0.01326 2.1466 0.7663 0.7630 56.04 0.7524 0.50 4.5 0.496 0.03971 1.2619 0.5963 0.9073 22.15 1.3520 4.6 0.498 0.03973 1.2817 0.6023 0.9066 22.10 1.3353 4.7 0.500 0.03974 1.3014 0.6082 0.9058 22.06 1.3189 4.8 0.503 0.03974 1.3211 0.6140 0.9051 22.02 1.3030 4.9 0.506 0.03974 1.3408 0.6195 0.9043 22.02 1.28741.0 3.2 0.494 0.08124 0.7993 0.3433 1.0080 12.15 2.0554 3.3 0.497 0.08139 0.8101 0.3515 1.0100 12.15 2.0340 3.4 0.500 0.08147 0.8208 0.3594 1.0112 12.15 2.0247 3.5 0.502 0.08150 0.8314 0.3670 1.0126 12.17 2.0096 3.6 0.505 0.08149 0.8419 0.3745 1.0139 12.18 1.99472.0 2.7 0.494 0.11467 0.6476 0.1688 1.0482 9.06 2.4181 2.8 0.497 0.11505 0.6536 0.1752 1.0525 9.06 2.4124 2.9 0.500 0.11529 0.6594 0.1815 1.0564 9.08 2.4062 3.0 0.503 0.11537 0.6652 0.1876 1.0602 9.10 2.3998 3.1 0.506 0.11537 0.6710 0.1936 1.0636 9.12 2.39314.0 2.5 0493 0.13234 0.5895 0.0751 1.0620 8.00 2.5802 2.6 0.497 0.13300 0.5928 0.0787 1.0679 8.00 2.5831 2.7 0.500 0.13342 0.5961 0.0822 1.0735 8.01 2.5878 2.8 0.503 0.13364 0.5992 0.0856 1.0787 8.04 2.5868 2.9 0.506 1.3370 0.6023 0.0890 1.0836 8.07 2.5852______________________________________
As is evident from Table 8, the design of centrally pivoted pads are feasible using quadratic surface profiles for a wide range of L z /L x ratios.
Characteristics of a centrally pivoted square shoe bearing with a convex surface profile for Type 1 and Type 2 boundary conditions are reproduced in tabular form from FIGS. 7, 8, 9, and 10 of reference [38] in Table 9.
TABLE 9______________________________________Performance coefficient K.sub.p for a centrally pivoted square shoebearing with a convex surface profile (Reference [38]).Type 1 Boundary Condition Type 2 Boundary Conditionh.sub.1 /h.sub.2 δ/h.sub.0 K.sub.p δh.sub.0 K.sub.p______________________________________4.0 2.08 0.0546 3.0 0.04953.0 1.12 0.0716 1.0 0.07712.0 0.35 0.0676 0.5 0.0716______________________________________
Once again, as observed in the case of an infinitely wide bearing, the quadratic surface profile offers a better load carrying capacity as compared to a convex surface profile where performance is very sensitive to maintaining in practice the optimum value range of δ/h O .
For a range of l z /L x ratios, Table 10 shows a comparative view of K p's for centrally pivoted shoes with quadratic surface profiles and an optimum conventional flat shoe with an offset pivot. It should be observed from Table 10 that the embodiment of the present invention which includes a quadratic surface 26, not only has a capability of attaining reversibility of operation, but also provides a gain of 35.62% in load carrying capacity over the conventional optimum flat surface design for L z /L x ratio of 0.25.
The design chart in FIG. 13 has been developed for the analysis and design of a centrally pivoted shoe bearing 10. Because the location of pivot 19 is fixed at the center for this embodiment, there are only 5 independent design variables, h O , L x , L z , U and μ, which affect the load carrying capacity and other characteristics of centrally pivoted shoe bearing 10. Six nondimensional performance coefficients are applicable: load coefficient, K p ; flow coefficient, K Q ; side flow ratio coefficient, R Q ; friction force coefficient, K f ; the coefficient of friction coefficient, K c ; and temperature rise coefficient, K T . K x is inapplicable.
The following examples illustrate the use of the design chart given in FIG. 13.
EXAMPLE 3
Centrally pivoted shoe 18, capable of attaining reversibility of operation, is to be designed having an L z /L x =0.5 in order to carry a load of 3500 lbf (15568.7N) and experience a minimum film thickness of 0.002 in. (0.0508 mm) for slider velocity U of 1200 in./sec. The same lubricant 28 as in Examples 1 and 2 will be used.
Using FIG. 13, for R t =0.5: α=4.7, K p =0.03874, K Q =1.3014, R Q =0.6082, K f =0.9058, K c =22.06 and K T =1.1389.
As in Example 1, the coefficient of viscosity μ at inlet temperature 120° F. is calculated to be 4.5579×10 -6 lbf-S/in 2 . Substituting L z =R t L x in equation (3), ##EQU5## As in Example 1, ΔT must be balanced such that the average film temperature, as determined from viscous losses, coincides with the temperature-viscosity property of the given lubricant 28. Repeating the heat balance loop for six iterations, the final value of μ at average temperature 140.75° F. is 2.9031×10 -6 lbf-S/in 2 . From equations (1) to (9),
L z =2.9259 in. (74.318 mm)
Q T =9.1386 in. 3 /sec (149.755 cm 3 /S)
Q z =5.5581 in. 3 /sec (91.08 cm 3 /S)
frictional horsepower=4.9573 horsepower (3696.66 W)
f=0.0075
ΔT=41.5249° F. (5.29° C.)
The quadratic surface 26 is obtained by machining a conventional flat surface shoe 18 with the calculated dimensions of L z and L x such that surface 24 is defined by the quadratic surface equation given above for α=4.7.
EXAMPLE 4
Centrally pivoted shoe 18 whose dimensions are given as L x =12 in. (304.8 mm) and L z =9.00 in. (228.6 mm) is to employ the same lubricant 28 as used in Examples 1, 2 and 3 and a thrust collar 24 velocity of 500 in/sec (12.7 m/sec). Shoe 18 has a load carrying capacity of 12000 lbf (53378.4N).
To design such a shoe 18, the minimum film thickness h O must be determined, balancing ΔT. For R t =9/12=0.75 from FIG. 13, the properties of shoe 18 are: α=3.78, K p =0.06292, K Q =0.975, R Q =0.4444, K f =0.965, K c =15.00, K T =1.7292.
As in Example 2, ##EQU6##
As in Example 2, the value of ΔT must be balanced. Thus, ##EQU7## and average temperature
T.sub.avg =129.3464° F. (54.0183° C.)
At this temperature,
μ=3.7051×10.sup.-6, and
h.sub.O =0.003548 in. (0.0901 mm)
ΔT=18.6907° F.
T.sub.avg =129.3453° F. (54.0807° C.)
Hence, using equations (1-9):
Q.sub.T =15.5669 in.sup.3 /sec (255.096 cm.sup.3 /S)
Q.sub.z =6.9179 in.sup.3 /sec (113.364 cm.sup.3 /S)
frictional horsepower=4.1225 horsepower (3074.148 W) and
f=0.0044
It will be appreciated that the thrust bearing shoe of the present invention is not limited to oil lubricated thrust bearings; it is applicable as well to gas bearings. The present invention may also be used in fixed shoe bearings where the shoes have fixed inclinations.
The bearings of the present invention have several advantages over prior art flat surface shoe bearings:
1. The load carrying capacity of the pivoted shoe thrust bearing constructed in accordance with the present invention is considerably higher than that of prior art bearings.
2. For the same value of minimum film thickness, the improved load carrying capacity of the present invention increases the margin of safety.
3. The load carrying capacity of a thrust bearing is directly proportional to the speed. Therefore the high load capacity at low rotor speeds of the present invention increases the range of applications for which these bearings are applicable. Longer bearing life is achieved where load capacities are generated at a lower speed.
4. For equal load carrying capacities, the bearings of the present invention need lesser shoe area as compared to prior art and thereby reduce the size and space required for the bearing. Reduction in size and space ultimately reduces the material cost.
5. The improved load carrying capacity of the present invention leads to better stiffness charcteristics, thereby improving dynamic stability.
6. The embodiments which incorporate a quadratic surface profile provide a unique opportunity to attain reversibility of operation with an improved load carrying capacity as compared to prior art bearings.
While only certain embodiments of the present invention have been described in detail herein and shown in the accompanying Drawings, it will be evident that various further modifications are possible without departing from the scope of the invention. | An improved thrust bearing shoe and method for making same is provided. The bearing shoe includes a surface having an optimum one-dimensional curved profile maximized as to load carrying capacity in accordance with predetermined relationships for the dimensions of the shoe. The curved profile may be cycloidal, truncated cycloidal, cubic or quadratic in shape depending on the dimensions of the shoe. | 5 |
BACKGROUND OF THE INVENTION
[0001] This invention relates to automatic resetting targets arranged in an upright position with all targets on the same vertical and horizontal plane. The targets drop when hit by a bullet or projectile and remain down until the reset target is also hit by a bullet or projectile. This would allow for constant shooting by the Shooter, and therefore would be challenging. Challenging the shooter's ability is one of the joys of target shooting. Targets that reset rapidly without swinging would result in faster shooting since the Shooter does not have to wait for the target to stop swinging. It is also desirable to be able to shoot safely at the target from different shooting positions, for example, Prone, Benchrest, and Kneeling. Targets that could be placed on a bench or close to the ground would make shooting from different positions easier. Simplicity in its operation and ease of manufacture would be very desirable. The shooting gallery should be stable enough to keep it from moving about when hit by a bullet or projectile and light enough for ease of carry. The operating mechanism must be protected from a damaging hit from a bullet or projectile.
SUMMARY OF THE INVENTION
[0002] The invention is a shooting gallery made up of numerous targets that are in an up right vertical position, spaced evenly on the same vertical and horizontal plane. All the targets pivot on a horizontal shaft that extends the length of the shooting gallery. Compression springs and spacers along the shaft assist the extension springs in holding the targets up right in a vertical position. The extension spring is attached at one end to the bottom of the target leg and the other end is attached to a rod that is mounted on the back support frame. The said extension spring holds the back portion of the target leg firmly against the front edge of the back support frame. When the target is hit by a bullet or projectile, with ample force, the target will pivot back and down stretching and loading the extension springs enough to lift the target when released. A latch made into the bottom of the target leg will come into contact with the catch bar preventing the target from returning to its original position. The catch bar running the length of the shooting gallery, and attached at both ends, is allowed to pivot freely. All the targets operate the same way except the reset target which does not have a latch. The catch bar is held into position just far enough to allow the target latch to pass by and come into contact with the catch bar. The catch bar is held into above said position with an adjustable stop. When the reset target is hit by a bullet or projectile it will pivot back and down in the same manner as the other targets. The bottom portion of the reset target is radiused so that when the target is almost all the way down the radiused end will come in contact with and move the catch bar to release the targets. The reset target returns to its original position and the sequence starts over. Compression springs and spacers between the targets maintain the targets in an up right position and compensate for wear.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] [0003]FIG. 1 is a top perspective view of the Automatic Resetting Shooting Gallery
[0004] [0004]FIG. 2 is an end view thereof
[0005] [0005]FIG. 3 is a top plan view thereof showing one target lying down after being hit by a bullet or projectile.
[0006] [0006]FIG. 4 is a cross-section taken along line 4 - 4 of figure three showing one upright target.
[0007] [0007]FIG. 5 is a cross-section taken along lines 5 - 5 of figure three showing one target being held down after being hit.
[0008] [0008]FIG. 6 is a cross-section taken along lines 6 - 6 of figure three showing the farthest right target about to be hit while the other targets are held down after being hit.
[0009] [0009]FIG. 7 is a view similar to figure six but with the end target falling while releasing all of the targets to spring up to the reset position.
DETAILED DESCRIPTION OF THE INVENTION
[0010] [0010]FIG. 1 shows the Automatic Resetting Shooting Gallery with multiple targets numbered 10 . All targets are in the vertical upright position before being hit by a bullet or projectile. All the targets are arranged along the same vertical and horizontal plane. The individual targets are made preferably of metal or other material capable of resisting the continued impact of a bullet or other projectile. The support frame consists of a front angle support 11 which extends upward to protect the target support shaft 12 , spacers 13 , compression springs 14 , target latch 15 , extension springs 16 , and the catch mechanism consisting of catch angle bar 22 , support shaft 21 , stop 23 , washers 24 , and locking collars 25 . The other side or surface of front angle support 11 forms the base for the Automatic Resetting Shooting Gallery to sit; said surface of front angle support 11 also forms a support base for side support angles 17 .
[0011] Side support angles 17 are attached to front angle support 11 by welding or other means of secure attachment. Side support angles 17 are so positioned as to form the outside surface of the support frame and also forms a base to sit the rear support angle 18 . Rear support angle 18 is so positioned so that one surface forms the outside edge of the frame with the other surface inside the frame and rests on the side support angle 17 . Front support angle 11 , side support angles 17 , and rear support angle 18 are welded together or firmly attached by other means to form the rectangular support frame and base of the Automatic Resetting Shooting Gallery.
[0012] [0012]FIG. 2 of the Automatic Resetting Shooting gallery is an end view showing front angle 11 , and side support angle 17 . Side support angle 17 has a spacer 19 made of metal, wood, or other material attached by welding or other means to firmly attach the spacer 19 . Spacer 19 will make up the difference of front angle support 11 to hold the Automatic Resetting Shooting Gallery level. Front support angle 11 is positioned so that one surface extends vertically upward to form the front surface of the shooting gallery, the other surface of said front support angle 11 is positioned inward and flat to form the base of the Automatic Resetting Shooting Gallery. The side support angle 17 is placed on the flat base surface of front angle 11 so that one surface of said side support angle 17 is in a vertical upright position to form the outside surface of the support frame, the other surface of said side support angle 17 is placed inward and rests flat on the base of front support angle 11 . Side support angle 17 is notched slightly to seat shaft 12 , a washer 20 is attached to said side support angle 17 to accept and hold said shaft 12 . Shaft 12 extends the length of the Automatic Resetting Shooting Gallery and is held in place on end support angle 17 by lock collars 25 or other suitable means.
[0013] Side support angle 17 has a hole drilled through on the outside vertical surface towards the front of the Automatic Resetting Shooting Gallery, the said hole is slightly larger than shaft 21 to allow rotation. Individual targets 10 are attached to the top portion of target legs 27 and target leg 26 by welding or other secure means of attachment, and said target legs 26 and 27 have a hole drilled through to allow mounting on shaft 12 so that said target legs 26 and 27 can pivot freely.
[0014] [0014]FIG. 3 is a top plain view showing one target after being hit by a bullet or projectile. Targets 10 when hit by a bullet or projectile of sufficient force will cause said target 10 to fall back and down, whereas target legs 26 and 27 pivot upon shaft 12 stretching and loading extension springs 16 . Latch 15 is in contact with catch bar 22 , and said catch bar 22 is held in position by adjustable stop 23 and adjustable stop 30 . Extension springs 16 are attached at one end to a rod 28 that extends the inside length of the rear support angle 18 . Rod 28 is secured to rear support angle 18 by welding or any other means to firmly attach and allow springs 16 to be connected. Center shaft support 29 has a hole drilled through it to allow shaft 12 to pass through. Center shaft support 29 is attached to rear support angle 18 . Latch 15 is made from one piece of wire that is inserted through a hole drilled in target legs 27 and bent to allow said latch 15 to pivot freely. One end of the wire is carried back towards the top of the said target leg 27 and wrapped over the front edge to form the latch stop when the bottom of said latch 15 is in contact with catch bar 22 . The other end of the wire is bent down toward the bottom of said target leg 27 , bent perpendicular across the bottom edge and close enough to the bottom edge of said target leg 27 to form a stop for latch 15 when not in contact with said catch bar 22 .
[0015] Spacers 13 of round tubing are placed over shaft 12 and between target legs 27 and target leg 26 to provide even spacing of targets 10 . Washers 24 are placed on each side of target legs 27 and target leg 26 . Spacers 13 are cut to length to allow even spacing of target 10 . Compression springs 14 are placed over shaft 12 and on each side of the center target 10 so as to force target legs 27 , target leg 26 , spacers 13 , and washers 24 towards the locking collars 25 . Therefore, said target legs 27 and target leg 26 are held in a perpendicular position.
[0016] [0016]FIG. 4 is a cross-section taken along line 4 - 4 of FIG. 3 showing one upright target. Target leg 27 is supported on shaft 12 and is allowed to pivot backwards. Extension springs 16 attached to the bottom and back portion of target leg 27 at one end, and attached to rod 28 at the other end, holds said target leg 27 against rear support angle 18 . Latch 15 is in a relaxed position. Catch bar 22 is in the reset position.
[0017] [0017]FIG. 5 is a cross-section taken along lines 5 - 5 of FIG. 3 showing one target being held down after being hit by a bullet or other projectile. Target 10 after being hit by a bullet or other projectile forces target leg 27 to pivot backward onto shaft 12 until said target leg 27 contacts the edge of rear support angle 18 . At the same time, extension springs 16 are stretched and loaded to pull target leg 27 back down. Latch 15 is now in a position to contact catch bar 22 , therefore preventing the target leg 27 from returning to the upright position. The top portion of latch 15 is now in contact with the front edge of target leg 27 preventing it from rotating.
[0018] [0018]FIG. 6 is a cross-section taken along lines 6 - 6 of FIG. 3 showing the farthest right target about to be hit while the other targets are held down after being hit. Catch bar 22 is held in its normal position by adjustable stop 23 and adjustable stop 30 . Adjustable stop 23 is attached to catch bar 22 so as to weigh one edge of said catch bar 22 to hold said catch bar 22 and adjustable stop 23 against adjustable stop 30 . Target 10 and reset target leg 26 are in their normal upright position held against rear support angle 17 by extension spring 16 .
[0019] [0019]FIG. 7 is a view similar to FIG. 6 but with the end target falling while releasing all of the targets to spring up to the normal upright position. Target 10 , attached to reset target leg 26 , is forced back and down by a bullet or other projectile until said reset target leg 26 contacts rear support angle 17 . The radiused end of reset target leg 26 contacts catch bar 22 causing said catch bar 22 to pivot away from adjustable stop 30 releasing all targets. Reset target leg 26 is pulled back down by extension spring 16 until it stops against rear support angle 17 . Catch bar 22 and adjustable stop 23 simultaneously pivots back to the normal position against adjustable stop 30 . The process is ready to repeat. | An automatic resetting target apparatus consisting of multiple knockdown targets and a reset target on the same vertical and horizontal plane. The knockdown targets, when hit by a bullet or other projectile, will fall backward and down. The knockdown targets will remain down until the reset target is hit by a bullet or other projectile. All targets will then return to their original upright position allowing for continuous shooting. | 5 |
This is a continuation-in-part of U.S. application Ser. No. 07/499,918, filed Mar. 27, 1990, now pending.
BACKGROUND OF THE INVENTION
3,5-Ditertiarybutyl-4-hydroxyphenyl is disclosed as a moiety in a variety of compounds.
For example, U.S. application Ser. No. 07/277,171, filed Nov. 29, 1988, now abandoned, and U.S. application Ser. No. 07/426,814, filed Oct. 30, 1989, pending. This moiety linked to thiadiazoles, oxadiazoles, and triazoles. However, the present compounds differ from this disclosure by the addition of either a carbonyl, an oxygen, carbon containing oxime, a sulfur, an oxygenated sulfur, or alkyl carbonyl moieties between the 3,5-di-tertiarybutyl-4-hydroxyphenyl and a 1,3,4-thiadiazole or oxadiazole ring.
Other references disclose compounds combining a 3,5-ditertiarybutyl-4-hydroxyphenyl with various other rings such as pyrazoles, isoxazoles or imidazoles. See copending Application U.S. application Ser. No. 06/861,179, filed May 9, 1986, now abandoned; U.S. application Ser. No. 06/910,692, filed Sept. 26, 1986, now abandoned; U.S. application Ser. No. 07/032,730, filed Apr. 6, 1987, now abandoned; and U.S. application Ser. No. 07/395,165, filed Aug. 16, 1989, now pending. However, such references differ from the present invention in both the heteroaryl ring moiety and the substituent between the heteroaryl ring and the 3,5-ditertiarybutyl-4-hydroxylphenyl moiety. The present invention is limited to rings having three heteroatoms together with a CO, S, S(O) n , O, O(CH 2 ) m , ##STR1## S(O) n (CH 2 ) m , (CH 2 ) m , or CO(CH 2 ) m between the rings.
SUMMARY IN THE INVENTION
The present invention is a novel compound of the Formula I ##STR2## and pharmaceutically acceptable base or acid addition salt thereof; in which A is CO, C=NOH, S(O) n (CH 2 ) m , S(O) n , (CH 2 ) m , CO(CH 2 ) m , O, or O(CH 2 ) m ; wherein X is O, or S;
Y is H, OH, SH, NH 2 , NHCN, ##STR3## SCH 3 , SOCH 3 or
SO 2 CH 3 ; R is hydrogen or lower alkyl; and
n is an integer of zero, one or two; and m is an integer of one or two with the proviso that when A is (CH 2 ) 2 and Y is OH then X cannot be O.
The present invention is also a pharmaceutical composition for treating a disease or condition, such as rheumatoid arthritis, osteoarthritis, other inflammatory conditions, psoriasis, allergic diseases, inflammatory bowl disease, GI ulcers, cardiovascular conditions including ischemic heart disease, and atherosclerosis and ischemia-induced cell damage particularly brain damage caused by stroke; preferably antiinflammatory disease or condition, comprising an antiinflammatory, antipsoriatic, antiallergy, antiulcer, or antiischemic, antiatherosclerotic, or cytoprotective amount of the compound of the Formula I or as a pharmaceutically acceptable salt thereof as defined above and a pharmaceutically acceptable carrier.
The present invention is also a method of treating a disease or condition as noted above in a mammal, particularly a human, suffering therefrom which comprises administering a compound of the Formula I or salt thereof as defined above in unit dosage form.
The invention also provides for use of any such compound of Formula I or salt thereof in the manufacture of a medical therapeutic agent.
The pharmaceutical composition or method of treating which is the present invention is meant to include what is understood to be prophylactic to one of a foregoing named disease or condition.
The compounds of the Formula I have activity as inhibitors of 5-lipoxygenase, cyclooxygenase or both to provide the use for the pharmaceutical composition and methods of the present invention.
A preferred compound of the Formula I is
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-oxadiazole-2(3H)-thione,
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-oxadiazol-2(3H)-one,
2,6-Bis(1,1-dimethylethyl)-4-[(1,3,4-thiadiazol-2-yl)thio]phenol,
2,6-Bis(1,1-dimethylethyl)-4-[2-(1,3,4-oxadiazol-2-yl)ethyl]phenol,
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-thiadiazole-2(3H)-thione,
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxy-phenylthio]ethyl]-1,3,4-oxadiazol-2(3H)-one,
2,6-Bis(1,1-dimethylethyl)-4-[[2-(1,3,4-oxadiazol-2-yl)ethyl]thio]phenol, and
(5-Amino-1,3,4-thiadiazol-2-yl)[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methanone.
More preferred are
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-thiadiazole-2(3H)-thione,
5-[2-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]ethyl-1,3,4-oxadiazol-2(3H)-one,
2,6-Bis(1,1-dimethylethyl)-4-[[2-(1,3,4-oxadiazol-2-yl)ethyl]thio]phenol, and
(5-Amino-1,3,4-thiadiazol-2-yl)3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methanone.
The most preferred is
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]-thio]-1,3,4-oxadiazole-2(3H)-thione.
DETAILED DESCRIPTION OF THE INVENTION
In the present invention "lower alkyl" is alkyl of from one to six carbons, inclusive, and means methyl, ethyl, propyl, butyl, pentyl or hexyl and isomers thereof.
"Halogen" is chloro, iodo, bromo or fluoro.
Me is methyl.
The compounds of the invention may contain geometric isomers. Thus, the invention includes the individual isomers and mixtures thereof. The individual isomers may be prepared or isolated by methods known in the art.
A tautameric form of selected compounds of Formula I would be recognized by an ordinarily skilled artisan to be within the present invention.
The compounds of Formula I are useful both in the free base and where possible the free acid form or in the form of base salts thereof, as well as, in the form of acid addition salts. All forms are within the scope of the invention. In practice, use of the salt form amounts to use of the free acid or free base form. Appropriate pharmaceutically acceptable salts within the scope of the invention are those derived from mineral acids such as hydrochloric acid and sulfuric acid; and organic acids such as methanesulfonic acid, benzenesulfonic acid, maleic acid, p-toluenesulfonic acid, and the like, giving the hydrochloride, sulfamate, methanesulfonate, benzenesulfonate, p-toluenesulfonate, and the like, respectively, or those derived from bases such as suitable organic and inorganic bases. Examples of suitable inorganic bases for the formation of salts of compounds of this invention include the hydroxides, carbonates, and bicarbonates of ammonia, sodium, lithium, potassium, calcium, magnesium, aluminum, zinc, and the like.
Salts may also be formed with suitable organic bases. Bases suitable for the formation of pharmaceutically acceptable base addition salts with compounds of the present invention include organic bases which are nontoxic and strong enough to form such salts. These organic bases form a class whose limits are readily understood by those skilled in the art. Merely for purposes of illustration, the class may be said to include mono-, di-, and trialkylamines, such as methylamine, dimethylamine, and triethylamine; choline; mono-, di-, or trihydroxyalkylamines such as mono-, di-, and triethanolamine; amino acids such as arginine, and lysine; choline; guanidine; N-methylglucosamine; N-methylpiperazine; morpholine; ethylenediamine; N-benzylphenethylamine; tris(hydroxymethyl) aminomethane; and the like. (See for example, "Pharmaceutical Salts," J. Pharm. Sci., 66(1), 1-19 (1977).)
The acid addition salts of said compounds are prepared either by dissolving the free base of compound I in aqueous or aqueous alcohol solution or other suitable solvents containing the appropriate acid or base and isolating the salt by evaporating the solution, or by reacting the free base of compound I with an acid as well as reacting compound I having an acid group thereon with a base such that the reactions are in an organic solvent, in which case the salt separates directly or can be obtained by concentration of the solution.
The base salts of compounds of Formula I described above are prepared by reacting the appropriate base with a stoichiometric equivalent of the acid compounds of Formula I to obtain pharmacologically acceptable base salts thereof.
The present invention also includes the solvates or hydrates of compounds of this invention, when possible, and are prepared or isolated by methods known in the art.
The usefulness of the compounds of the present invention as inhibitors of the 5-lipoxygenase enzyme, cyclooxygenase, or in treating related diseases or conditions may be demonstrated by their effectiveness in various standard test procedures. A description of each procedure follows.
ARBL/ARBC Whole Cell 5-Lipoxygenase and Cyclooxygenase Assays
Materials
The rat basophilic leukemia cell line (RBL-1) was obtained from the American Type Culture Collection (Rockville, MD).
Radioimmunoassay (RIA) kits of LTB 4 and PGF 2 .sbsb.α were obtained from Amersham (Arlington Heights, Ill.) and Seragen (Boston, Mass.), respectively.
All tissue culture media were obtained from GIBCO (Grand Island, N.Y.).
Method
RBL-1 cells are grown in suspension culture in Eagle's minimum essential medium supplemented with 12% fetal bovine serum at 37° C. in an incubator supplied with air-5% carbon dioxide. Cells are harvested by centrifugation. They are washed with cold phosphate buffered saline pH 7.4 (PBS; NaCl, 7.1 g; Na 2 HPO 4 , 1.15 g; KH 2 PO 4 , 0.2 g; and KCl, 0.2 g/L). Cells are finally suspended in PBS containing 1.0 mM calcium at a density of 2×10 6 cells/mL. Cells are incubated with and without test agent (in DMSO) (1% DMSO is without effect on arachidonic acid metabolism) for ten minutes at room temperature. Calcium ionophore A23187 (5 μM) is added and cells are incubated for 7 minutes at 37° C. The reaction is stopped by chilling the tubes on ice for 10 minutes. Cells are separated by centrifugation and the supernatant is stored at -20° C. Aliquots (100 μL) are analyzed for LTB 4 and PGF 2 .sbsb.α using radioimmunoassay kits as provided by the supplier.
Table 1 contains biochemical data obtained from this whole cell assay as IC 50 s which are calculated as the amount of test compound causing 50% inhibition or percent of inhibition at the named micromoles (μM) of LTB 4 or PGF 2 .sbsb.α formation.
Carrageenan-Induced Rat Foot Paw Edema-2 (CFE-2) Assay: Protocol
Carrageenan solution (1% w/v) is prepared by dissolving 100 mg carrageenan (Marine Colloidal Div., Springfield, N.J.) in 10 mL of sterile saline (0.9) solution (Travenol). The solution is vortexed for 30 to 45 minutes. Animals are dosed with compound 1 hour before carrageenan challenge. Foot paw edema is induced by injecting 0.10 mL of the 1% carrageenan subcutaneously into the plantar portion of the right hind paw of each rat under light anesthesia. Initial foot paw volume is measured immediately following carrageenan challenge using mercury plethysmography (Buxco Electronics). Edema is measured 5 hours after carrageenan. The difference between the 5-hour and the initial paw volume is expressed as delta edema. The delta edema for each test group of animals is used to calculate the percent inhibition of edema achieved by the compound at the test dose compared with the vehicle control group. The data in Table 1 (the dose at which swelling is inhibited by the noted) is calculated by probit analysis for the dose at which percent inhibition occurs.
TABLE 1______________________________________ ##STR4##Example A X Y ARBL ARBC CFE______________________________________ 6 S O OH 91 @ 16.sup.b 46 @ 16.sup.d 7 S O SH 2.sup.a 1.5.sup.c 8.6.sup.f 8 S S OH 90 @ 16.sup.b N.sup.e 9 S S SH 1.1.sup.a 3.6.sup.c10 S S H 59 @ 10.sup.b 54 @ 10.sup.d13 S(CH.sub.2).sub.2 O OH 0.6.sup.a 75 @ 10.sup.d14 S(CH.sub.2).sub.2 O SH 4.2.sup.a N.sup.c15 S(CH.sub.2).sub.2 O H 100 @ 10.sup.b 55 @ 10.sup.d16 S(CH.sub.2).sub.2 O NH.sub.2 100 @ 10.sup.b N.sup.e23 (CH.sub.2).sub.2 O OH 60 @ 10.sup.b N.sup.e25 (CH.sub.2).sub.2 O H 100 @ 10.sup.b 52 @ 10.sup.d26 (CH.sub.2).sub.2 O NH.sub.2 40 @ 10.sup.b N.sup.e29 CO S NH.sub.2 1.1.sup.a 5.2.sup.c30 CO S SMe 100 @ 10 100 @ 1031 CO S SH 100 @ 10 92 @ 10______________________________________ .sup.a IC.sub.50 for LTB.sub.4 inhibition .sup.b Percent inhibition of LTB.sub.4 @ μM noted .sup.c IC.sub.50 for PGF.sub.2.sbsb.α inhibition .sup.d Percent inhibition of PGF.sub.2.sbsb.α @ 10 μM .sup.e N is not active at the dose tested .sup.f ID.sub.40 (mg/kg) for inhibition of swelling
Accordingly, the present invention also includes a pharmaceutical composition for treating one of the above diseases or conditions comprising an antidisease effective amount or an amount effective for the inhibition of 5-lipoxygenase, cyclooxygenase or both of a compound of the Formula I or salt thereof, as defined above together with a pharmaceutically acceptable carrier.
The present invention further includes a method for treating one of the above named diseases or conditions in mammals, including man, suffering therefrom comprising administering to such mammals either orally or parenterally, preferably oral, a corresponding pharmaceutical composition containing a compound of the Formula I or salt thereof.
A physician or veterinarian of ordinary skill readily determines a subject who is exhibiting symptoms of any one or more of the diseases described above. Regardless of the route of administration selected, the compounds of the present invention of the Formula I as described in pharmaceutical compositions above are formulated into pharmaceutically acceptable dosage forms by conventional methods known to the pharmaceutical art.
The compounds can be administered in such oral unit dosage forms as tablets, capsules, pills, powders, or granules. They also may be administered rectally or vaginally in such forms as suppositories or bougies; they may also be introduced parenterally (e.g., subcutaneously, intravenously, or intramuscularly), using forms known to the pharmaceutical art. They are also introduced directly to an affected area (e.g., in the form of eye drops or by inhalation). For the treatment of asthma or allergies, particularly dermatological disorders; such as erythema, psoriasis and acne, the compounds may also be administered topically in the form of ointments, gels, or the like However, in general, the preferred route of administration is orally.
An effective but nontoxic quantity of the compound is employed in treatment. The ordinarily skilled physician or veterinarian will readily determine and prescribe the effective amount of the compound to prevent or arrest the progress of the condition for which treatment is administered. In so proceeding, the physician or veterinarian could employ relatively low dosages at first, subsequently increasing the dose until a maximum response is obtained.
In determining when a lipoxygenase, cyclooxygenase, or dual lipoxygenase/cyclooxygenase inhibitor is indicated, of course inter alia, the particular condition in question and its severity, as well as the age, sex, weight, and the like of the subject to be treated, must be taken into consideration and this determination is within the skill of the attendant physician.
For medical use, the amount required of a compound of Formula I or pharmacologically acceptable salt thereof to achieve a therapeutic effect will, of course, vary both with the particular compound, the route of administration, the mammal under treatment, and the particular disorder or disease concerned. A suitable dose of a compound of Formula I or pharmacologically acceptable salt thereof for a mammal suffering from, or likely to suffer from any condition as described hereinbefore is 0.1 μg-500 mg of the compound per kilogram body weight. In the case of systemic administration, the dose may be in the range of 0.5 to 500 mg of the compound per kilogram body weight, the most preferred dosage being 0.5 to 50 mg/kg of mammal body weight administered two or three times daily. In the case of topical administration, e.g., to the skin or eye, a suitable dose may be in the range 0.1 ng-100 μg of the compound per kilogram, typically about 0.1 μg/kg.
In the case of oral dosing for the treatment or prophylaxis of arthritis or inflammation in general, due to any course, a suitable dose of a compound of Formula I or physiologically acceptable salt thereof, may be specified in the preceding paragraph, but most preferably is from 1 mg to 10 mg of the compound per kilogram, the most preferred dosage being from 1 mg to 5 mg/kg of mammal body weight, for example for 1 to 2 mg/kg.
It is understood that the ordinarily skilled physician or veterinarian will readily determine and prescribe the effective amount of the compound to prevent or arrest the progress of the condition for which treatment is administered. In so proceeding, the physician or veterinarian could employ relatively low doses at first, subsequently increasing the dose until a maximum response is obtained.
While it is possible for an active ingredient to be administered alone, it is preferable to present it as a pharmaceutical formulation comprising a compound of Formula I or a pharmacologically acceptable acid addition or base salt thereof and a pharmacologically acceptable carrier therefor. Such formulations constitute a further feature of the present invention.
In addition to the compounds of Formula I, the pharmaceutical compositions can also contain other active ingredients, such as cyclooxygenase inhibitors, nonsteroidal antiinflammatory drugs (NSAIDs), peripheral analgesic agents such as zomepirac, diflunisal, and the like. The weight ratio of the compound of the Formula I to the second active ingredient may be varied and will depend upon the effective dose of each ingredient. Generally, an effective dose of each will be used. Thus, for example, when a compound of the Formula I is combined with an NSAID, the weight ratio of the compound of the formula I to the NSAID will generally range from about 1000:1 to about 1:1000, preferably about 200:1 to about 1:200. Combinations of a compound of the Formula I and other active ingredients will generally also be within the aforementioned range, but in each case, an effective dose of each active ingredient should be used.
Combinations of a compound of the Formula I and other active ingredients will generally be in the aforementioned ratios.
NSAIDs can be characterized into five groups:
(1) the propionic acid derivatives;
(2) the acetic acid derivatives;
(3) the fenamic acid derivatives;
(4) the biphenylcarboxylic acid derivatives; and
(5) the oxicams or a pharmaceutically acceptable salt thereof.
The propionic acid derivatives which may be used comprise: ibuprofen, ibuprufen aluminum, indoprofen, ketoprofen, naproxen, benoxaprofen, flurbiprofen, fenoprofen, fenbufen, pirprofen, carprofen, oxaprozin, pranoprofen, miroprofen, tioxaprofen, suprofen, alminoprofen, tiaprofen, fluprofen, and bucloxic acid. Structurally related propionic acid derivatives having similar analgesic and antiinflammatory properties are also intended to be included in this group.
Thus, "propionic acid derivatives" as defined herein are nonnarcotic analgesics/nonsteroidal anti-inflammatory drugs having a free --CH(CH 3 )COOH or --CH 2 CH 2 COOH group (which optionally can be in the form of a pharmaceutically acceptable salt group, e.g., --CH(CH 3 )COO - NA + or --CH 2 CH 2 COO - Na + ), typically attached directly or via a carbonyl function to a ring system, preferably to an aromatic ring system.
The acetic acid derivatives which may be used comprise: indomethacin, which is a preferred NSAID, sulindac, tolmetin, zomepirac, diclofenac, fenclofenac, alclofenac, ibufenac, isoxepac, furofenac, tiopinac, zidometacin, acemetacin, fentiazac, clidanac, oxpinac, and fenclozic acid. Structurally related acetic acid derivatives having similar analgesic and antiinflammatory properties are also intended to be encompassed by this group.
Thus, "acetic acid derivatives" as defined herein are nonnarcotic analgesics/nonsteroidal antiinflammatory drugs having a free --CH 2 COOH group (which optionally can be in the form of a pharmaceutically acceptable salt group, e.g. --CH 2 COO - Na + ), typically attached directly to a ring system, preferably to an aromatic or heteroaromatic ring system.
The fenamic acid derivatives which may be used comprise: mefanamic acid, meclofenamic acid, flufenamic acid, niflumic acid, and tolfenamic acid. Structurally related fenamic acid derivatives having similar analgesic and antiinflammatory properties are also intended to be encompassed by this group.
Thus, "fenamic acid derivatives" as defined herein are nonnarcotic analgesics/nonsteroidal antiinflammatory drugs which contain the basic structure: ##STR5## which can bear a variety of substituents and in which the free --COOH group can be in the form of a pharmaceutically acceptable salt group, e.g., --COO - Na + .
The biphenylcarboxylic acid derivatives which can be used comprise: diflunisal and flufenisal. Structurally related biphenylcarboxylic acid derivatives having similar analgesic and antiinflammatory properties are also intended to be encompassed by this group.
Thus, "biphenylcarboxylic acid derivatives" as defined herein are nonnarcotic analgesics/nonsteroidal antiinflammatory drugs which contain the basic structure: ##STR6## which can bear a variety of substituents and in which the free --COOH group can be in the form of a pharmaceutically acceptable salt group, e.g., --COO - Na + .
The oxicams which can be used in the present invention comprise: piroxicam, sudoxicam, isoxicam, and 4-hydroxyl-1,2-benzothiazine 1,1-dioxide 4-(N-phenyl)-carboxamide. Structurally related oxicams having similar analgesic and antiinflammatory properties are also intended to be encompassed by this group.
Thus, "oxicams" as defined herein are nonnarcotic analgesics/nonsteroidal antiinflammatory drugs which have the general formula: ##STR7## wherein R is an aryl or heteroaryl ring system.
The following NSAIDs may also be used: acemetacin, alminoprofen, amfenac sodium, aminoprofen, anitrazafen, antrafenine, auranofin, bendazac lysinate, benzydamine, beprozin, broperamole, bufezolac, carprofen, cinmetacin, ciproquazone, clidanac, cloximate, dazidamine, deboxamet, delmetacin, detomidine, dexindoprofen, diacerein, di-fisalamine, difenpyramide, emorfazone, enfenamic acid, enolicam, epirizole, etersalate, etodolac, etofenamate, fanetizole mesylate, fenclofenac, fenclorac, fendosal, fenflumizole, fentiazac, feprazone, floctafenine, flunixin, flunoxaprofen, fluproquazone, fopirtoline, fosfosal, furcloprofen, furofenac, glucametacin, guaimesal, ibuproxam, isofezolac, isonixim, isoprofen, isoxepac, isoxicam, lefetamine HCl, leflunomide, lofemizole, lonazolac calcium, lotifazole, loxoprofen, lysin, clonixinate, meclofenamate sodium, meseclazone, microprofen, nabumetone, nictindole, nimesulide, orpanoxin, oxametacin, oxapadol, oxaprozin, perisoxal citrate, pimeprofen, pimetacin, piproxen, pirazolac, pirfenidone, pirprofen, pranoprofen, proglumetacin maleate, proquazone, pyridoxiprofen, sudoxicam, suprofen, talmetacin, talniflumate, tenoxicam, thiazolinobutazone, thielavin B, tiaprofenic acid, tiaramide HCl, tiflamizole, timegadine, tioxaprofen, tolfenamic acid, tolpadol, tryptamid, ufenamate, and zidometacin.
Finally, NSAIDs which may also be used include the salicylates, specifically aspirin, and the phenylbutazones, and pharmaceutically acceptable salts thereof.
Pharmaceutical compositions comprising the formula I compounds may also contain as the second active ingredient, antihistaminic agents such as benadryl, dramamine, histadyl, phenergan, and the like. Alternatively, they may include prostaglandin antagonists such as those disclosed in European Patent Application 11,067 or thromboxane antagonists such as those disclosed in U.S. Pat. No. 4,237,160. They may also α-fluoromethylhistidine, described in U.S. Pat. No. 4,325,961. The compounds of the formula I may also be advantageously combined with an H 1 or H 2 -receptor antagonist, such as for instance cimetidine, ranitidine, terfenadine, famotidine, temelastine, acrivastine, loratadine, cetrizine, tazifylline, azelastine, aminothiadiazoles disclosed in EP 81102976.8 and like compounds, such as those disclosed in U.S. Pat. Nos. 4,283,408; 4,362,736; 4,394,508, and European Patent Application No. 40,696. The pharmaceutical compositions may also contain a K + /H + ATPase inhibitor such as omeprazole, disclosed in U.S. Pat. No. 4,255,431, and the like. Each of the references referred to in this paragraph is hereby incorporated herein by reference.
The compounds of the Formula I are prepared generally by the following processes and constitute a further aspect of the present invention.
Generally, the compounds of Formula I are prepared by one of the following methods shown hereinafter in Schemes I, II, III, IV, and V. ##STR8##
Description of Scheme I
In Step 1 of Scheme I, a hydrazide of Formula II is treated with phosgene, or a phosgene equivalent such as 1,1'-carbonyldiimidazole, in the presence of 0-3 equivalents of an organic base such as triethylamine, pyridine, or preferably diisopropyethyl amine, to give an oxadiazolone of Formula Ia. Suitable solvents for this reaction include tetrahydrofuran and methylene chloride.
In Step 2, a hydrazide of Formula II is treated with an orthoformic ester, preferably triethyl orthoformate, along with a catalytic amount of an organic acid such as p-toluenesulfonic acid or a mineral acid such as HCl, either neat or in an alcoholic solvent, preferably ethanol, to provide an oxadiazole of Formula Ib.
In Step 3, a hydrazide of Formula II is dissolved in a suitable solvent such as tetrahydrofuran or dioxane and treated with cyanogen bromide followed by an aqueous solution of an inorganic base, such as sodium bicarbonate, to provide an amino-oxadiazole of Formula Ic.
In Step 4, a hydrazide of Formula II is treated with 1,1'-thiocarbonyldiimidazole or preferably thiophosgene, in the presence of 0-3 equivalents of an organic base such as diisopropylethylamine, in a solvent such as tetrahydrofuran to give an oxadiazolethione of Structure Id. This transformation can also be achieved by refluxing a solution of the hydrazide of Formula II with carbon disulfide in absolute ethanol or methanol in the presence of an inorganic base such as potassium hydroxide.
In Step 5, a hydrazide of Formula II is formylated in neat formic acid. Subsequent treatment of Intermediate III with phosphorous pentasulfide or other thionating agent, such as Lawesson's Reagent, in a solvent such as dioxane or tetrahydrofuran yields a thiadiazole of Formula Ie. ##STR9##
Description of Scheme II
In Scheme II, thiohydrazides of Formula IV are subjected to the same conditions used to convert hydrazides of Formula II to oxadiazoles of Formula Ia, Ib, Ic, and Id. The result is the preparation of thiadiazoles of Formula If, Ie, Ig, and Ih analogous to the aforementioned oxadiazoles. It should be noted that thiadiazoles of Formula Ie can also be prepared by the route shown in Scheme I. ##STR10##
Description of Scheme III
In Scheme III, saponification of ester 1 to compound 2 using an aqueous alkali base including KOH, NaOH, are LiOH in alcoholic and/or ethers solvents (such as tetrahydrofuran, diethyl ether, dioxane, t-butylmethyl ether, or diisopropyl ether) at temperatures from 0° C. to 100° C. for 1 hour to 7 days. The acid chloride 3 can be prepared from 2 using oxalyl chloride and a catalytic amount of N,N-dimethylformamide (DMF) in ether or halogenated solvents (such as dichloromethane, chloroform, dichloroethane, or dichlorobenzene). Thionylchloride may also be used for this conversion. Reaction temperatures can range from 0 to 100° C. for times of 1 hour to 7 days. Compound 3 can be treated with hydrazinecarbodithionic acid, methylester (4; Audrieth, L. F.; Scott, E. S.; Kippur, P. S., J. Org. Chem. 1954, 19, 733) in ether solvents at temperatures of 0° C. to 100° C. for 1 hour to 7 days to give compound 5. Treatment of 5 with acids such as hydrochloric acid, methanesulfonic acid, or p-toluenesulfonic acid in aromatic or ether solvents at 0° C. to 100° C. will give compound 6. Compound 7 can be prepared from 6 using sodium thiomethoxide in DMF at 0° C. to 100° C. for 1 hour to 7 days.
Compound 3 can also be treated with thiosemicarbazide in pyridine or ether solvents to give 9. Treatment of 9 with acids such as hydrochloric acid, methanesulfonic acid, or toluenesulfonic acids gives compound 10. ##STR11##
Description of Scheme IV
In Step 1 of Scheme IV, those compounds of Formula I where Y does not contain sulfur are treated with an equivalent amount of m-chloroperbenzoic acid in methylene chloride to provide compounds of Formula Ii. Other suitable oxidizing agents are KMnO 4 , NaIO 4 , and hydrogen peroxide. In Step 2, the use of two or more equivalents of oxidizing agent, again preferably m-chloroperbenzoic acid, converts compounds of Formula I to compounds of Formula Ij.
Description of Scheme V
In Step 1 of Scheme V, compounds of Formula Id or Ih are treated with iodomethane in the presence of a base such as potassium hydride, potassium t-butoxide, or preferably sodium hydroxide in a solvent such as dimethylformamide or preferably methanol to provide compounds of Formula Ik. In Step 2, those compounds of Formula Ik where A does not contain sulfur are oxidized with either 1 or 2 or more equivalents of an oxidizing agent, preferably m-chloroperbenzoic acid to give a compound of Formula Il where p=1 or 2*. In Step 3, compounds of Formula Il are treated with cyanamide or guanidine-HCl in the presence of an inorganic base preferably potassium t-butoxide in a solvent such as t-butanol to provide compounds of Formula Im. Compounds of Formula Im where Y'=NHCN can also be prepared by treatment of a compound of Formula Il with cyanamide and an organic base, preferably triethylamine, in a solvent such as dimethylformamide.
One of skill in the art would recognize variations in the sequence and would recognize variations in the appropriate reaction conditions from the analogous reactions shown or otherwise known which may be appropriately used in the processes above to make the compounds of the Formula I herein.
In the process described herein for the preparation of compounds of this invention the requirements for protective groups are generally well recognized by one skilled in the art of organic chemistry, and accordingly the use of appropriate protecting groups is necessarily implied by the processes of the charts herein, although such groups may not be expressly illustrated.
Introduction and removal of such suitable oxygen protecting groups are well-known in the art of organic chemistry; see for example "Protective Groups in Organic Chemistry," J. F. W. McOmie, ed., (New York, 1973), pages 43ff, 95ff, J. F. W. McOmie, Advances in Organic Chemistry, Vol. 3, 159-190 (1963); J. F. W. McOmie, Chem & Ind., 603 (1979), and T. W. Greene, "Protective Groups in Organic Synthesis", Wiley (New York) 1981, Chapters 2, 3, and 7.
Examples of suitable oxygen protecting groups are benzyl, trialkylsilyl, ethoxyethyl, methoxyethoxymethyl, methoxymethyl, trialkylsilylethyl, and the like.
The products of the reactions described herein are isolated by conventional means such as extraction, distillation, chromatography, and the like.
Starting materials not described herein are available commercially, are known, or can be prepared by methods known in the art.
The salts of the compounds of Formula I described above are prepared by reacting the appropriate base or acid with a stoichiometric equivalent of the compounds of Formula I.
The invention is further elaborated by the representative examples as follows. Such examples are not meant to be limiting.
EXAMPLE 1
3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl thiocyanate
3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl thiocyanate is prepared according to the method of European Patent Number 0 293 900, assigned to G.bD. Searle & Co.
EXAMPLE 2
2,6-Bis(1,1-dimethylethyl)-4-mercaptophenol
2,6-Bis(1,1-dimethylethyl)-4-mercaptophenol is prepared according to the method of European Patent Number 0 293 900, assigned to G. D. Searle & Co.
EXAMPLE 3
S,S-Bis[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]carbonodithioate
N,N-Diisopropylethylamine (21.6 mL, 125.8 mmol) is added to a -48° C. solution of 2,6-bis(1,1-dimethylethyl)-4-mercaptophenol (20.0 g, 84.0 mmol) in toluene (400 mL) followed by dropwise addition of a 12.5% solution of phosgene in toluene (33.2 g, 42.0 mmol). The reaction mixture is stirred for 1.5 hours then poured into a separatory funnel containing ethyl acetate and water. The aqueous phase is acidified to pH 3 with 1N hydrochloric acid. The organic phase is washed twice with water, then with a saturated solution of sodium bicarbonate followed by brine. Drying the organic phase over magnesium sulfate and evaporation of the solvents gives a heavy oil which is crystallized from isopropyl ether/hexane to afford 9.6 g (46%) of S,S-bis[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]carbonodithionate, mp 176.0-178.0° C.
Analysis for C 29 H 42 S 2 O 3 :
Calcd: C, 69.28; H, 8.42.
Found: C, 69.17, H, 8.50.
EXAMPLE 4
S-[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]hydrazinecarbothioate
A solution of S,S-bis[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl] carbonodithioate (5.0 g, 9.9 mmol) in dichloromethane (50 mL) is added dropwise to a 0° C. solution of hydrazine monohydrate (1.1 g, 22.0 mmol) in dichloromethane (60 mL). The ice bath is removed and the reaction is stirred vigorously for 48 hours. The reaction mixture is diluted with ethyl acetate and washed four times with water and once with brine. The organic phase is dried over magnesium sulfate and the solvents are evaporated in vacuo. The residue is chromatographed on a 100 g silica column with ethyl acetate/hexane (1/9 then 1/1). The hydrazide is crystallized from isopropyl ether to give 2.72 g (92%) of S-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl] hydrazinecarbothioate, mp 130.0-131.0° C.
Analysis for C 15 H 24 N 2 O 2 S:
Calcd: C, 60.78; H, 8.16; N, 9.45; S, 10.82.
Found: C, 61.05, H, 8.29; N, 9.49; S, 10.79.
EXAMPLE 5
3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl hydrazinecarbodithioate
Thiophosgene (1.6 mL, 21.0 mmol) is added dropwise to a -78° C. solution of 2,6-bis(1,1-dimethylethyl)-4-mercaptophenol (5.0 g, 21.0 mmol) and N,N-diisopropylethylamine (5.4 mL, 31.4 mmol) in toluene/dichloromethane (100 mL/20 mL). The reaction mixture is stirred for 1.5 hours then poured into a separatory funnel containing ethyl acetate and water. The aqueous phase is acidified to pH 3 with 1N hydrochloric acid. The organic phase is washed twice with water, then with a saturated solution of sodium bicarbonate followed by brine. Drying the organic phase over magnesium sulfate and evaporation of the solvents gives a crude product which is dissolved in dichloromethane (200 mL) and cooled to 0° C. Hydrazine monohydrate (1.5 mL, 31.0 mmol) is added in three portions at 30 minute intervals, and the solution is stirred for 1 hour. The reaction is poured into ethyl acetate and washed four times with an aqueous solution of sodium chloride and once with a saturated solution of sodium chloride. Drying the organic phase over magnesium sulfate and evaporation gives an amorphous solid which is crystallized from 50 mL of ethyl acetate/hexane (5/95) affording 3.5 g (53% from 2,6-bis(1,1-dimethylethyl)-4-mercaptophenol) of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl hydrazinecarbodithioate, mp 145.5°-146.0° C.
Analysis for C 15 H 24 N 2 OS 2 :
Calcd: C, 57.65; H, 7.74; N, 8.96.
Found: C, 57.30; H, 7.74; N, 8.68.
EXAMPLE 6
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-oxadiazol-2(3H)-one
A 12.5% solution of phosgene in toluene (13.0 mL, 13.5 mmol) is added dropwise to a -78° C. solution of S-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl] hydrazinecarbothioate (2.0 g, 6.8 mmol) and N,N-diisopropylethylamine (4.6 mL, 27.0 mmol) in tetrahydrofuran (200 mL). The reaction mixture is allowed to warm slowly to room temperature and stirred for 1 hour. The reaction is then poured into a separatory funnel containing ethyl acetate and water. The aqueous phase is acidified to pH 3 with 1N hydrochloric acid. The organic phase is washed twice with water, then with a saturated solution of sodium bicarbonate followed by brine. Drying the organic phase over magnesium sulfate and evaporation gives a solid which is chromatographed on a 200 g column of silica with acetone/hexane (15/85). Subsequent crystallization from dichloromethane/hexane affords 0.54 g (25%) of 5-[3,5-bis(1,1-dimethylethyl) -4-hydroxyphenyl]thio]-1,3,4-oxadiazol-2(3H)-one, mp 131.5°-134.0° C.
Analysis for C 16 H 22 N 2 O 3 S:
Calcd: C, 59.60; H, 6.88; N, 8.69.
Found: C, 59.80; H, 6.95; N, 8.44.
EXAMPLE 7
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-oxadiazole-2(3H)-thione
Thiophosgene (0.39 mL, 5.1 mmol) is added dropwise to a -78° C. solution of S-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl] hydrazinecarbothioate (1.5 g, 5.1 mmol) in tetrahydrofuran (150 mL). The reaction mixture is stirred for 10 minutes then poured into a separatory funnel containing ethyl acetate and aqueous sodium bicarbonate. The organic phase is washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a solid which is crystallized from dichloromethane/hexane affording 1.1 g (62%) of 5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-oxadiazole-2(3H)-thione, mp 129.0°-131.0° C.
Analysis for C 16 H 22 N 2 O 2 S 2 :
Calcd: C, 56.77; H, 6.55; N, 8.28.
Found: C, 57.00; H, 6.63; N, 8.19.
EXAMPLE 8
5[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-thiadiazol-2(3H)-one
A 12.5% solution of phosgene in toluene (8.6 mL, 9.6 mmol) is added dropwise to a -78° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl hydrazinecarbodithioate (1.5 g, 4.8 mmol) and N,N-diisopropylethylamine (3.3 mL, 19.2 mmol) in tetrahydrofuran (150 mL). The reaction mixture is stirred for 10 minutes then poured into a separatory funnel containing ethyl acetate and water. The pH of the aqueous phase is adjusted to 3 with 1N hydrochloric acid. The organic phase is washed twice with water, then with a saturated solution of sodium bicarbonate followed by brine. Drying over magnesium sulfate and evaporation of the solvents gives a solid which is crystallized twice from isopropyl ether/hexane to afford 0.7 g (43%) of 5-[[3,5-bis(1,1-dimethylethyl) -4-hydroxyphenyl]thio]-1,3,4-thiadiazol-2(3H)-one, mp 194°-197° C. (dec).
Analysis for C 16 H 22 N 2 O 2 S 2 :
Calcd: C, 56.77; H, 6.55; N, 8.28; S, 18.95.
Found: C, 56.62; H, 6.41; N, 7.97; S, 18.57.
EXAMPLE 9
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-thiadiazole-2(3H)-thione
Thiophosgene (0.37 mL, 4.8 mmol) is added dropwise to a -78° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl hydrazinecarbodithioate (1.5 g, 4.8 mmol) in tetrahydrofuran (150 mL). The reaction mixture is stirred for 10 minutes then poured into a separatory funnel containing ethyl acetate and aqueous sodium bicarbonate. The organic phase is washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a solid which is crystallized from ethyl acetate/hexane to afford 1.5 g (88%) of 5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4thiadiazole-2(3H)-thione, mp 181.0°-185.5° C.
Analysis for C 16 H 22 N 2 OS 3 :
Calcd C, 54.20; H, 6.25; H, 7.90.
Found: C, 53.84; H, 6.24; N, 7.72.
EXAMPLE 10
2,6-Bis(1,1-dimethylethyl)-4-[(1,3,4-thiadiazol-2-yl)thio]-phenol
A catalytic amount of p-toluenesulfonic acid (25 mg) is added to a stirring solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl hydrazinecarbodithioate (0.50 g, 1.6 mmol) and triethyl orthoformate (4 mL, 24 mmol) in ethanol (15 mL). After 10 minutes, 10 mL of 1N hydrochloric acid is added and stirring is continued for 30 minutes. The reaction mixture is diluted with ethyl acetate and washed twice with saturated solutions of sodium bicarbonate, twice with water, and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a crude product which is crystallized from dichloromethane/hexane to afford 0.37 g (72%) of 2,6-bis(1,1-dimethylethyl)-4-[1,3,4 -thiadiazol-2-yl)thio]-phenol, mp 182.5°-183.5° C.
Analysis for C 16 H 22 N 2 OS 2 :
Calcd: C, 59.59; H, 6.88; N, 8.69.
Found: C, 59.80; H, 6.93; N, 8.55.
EXAMPLE 11
Methyl 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]-thio]propanoate
(Ref. U.S. Pat. No. 4,539,159).
Methyl acrylate (1.1 g, 12.6 mmol) and triethylamine (0.5 mL, 0.4 mmol) are sequentially added to a room temperature solution of 2,6-bis(1,1-dimethylethyl)-4-mercaptophenol (3.0 g, 12.6 mmol) in acetonitrile (6 mL). The reaction is stirred for 1.5 hours and then evaporated under high vacuum to give 3.7 g (90%) of the crude product. A small portion is chromatographed on a silica column with ethyl acetate/hexane (1/9) to afford an analytically pure sample of methyl 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoate, mp 64.0°-66.0° C.
Analysis for C 18 H 28 O 3 S:
Calcd: C, 66.63; H, 8.70; S, 9.88.
Found: C, 66.78; H, 8.74; S, 9.92.
EXAMPLE 12
3-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide
Hydrazine monohydrate (16 mL, 324 mmol) is added to a room temperature solution of methyl 3-[[3,5-bis-(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoate (3.5 g, 10.8 mMol) in methanol (110 mL). The reaction mixture is heated at reflux for 2 hours, then cooled, diluted with ethyl acetate and washed six times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation provides a crude solid which is chromatographed on a column of silica with methanol/chloroform (5/95) to afford 2.4 g (64%) of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide, mp 107.0°-110.0° C.
Analysis for C 17 H 28 N 2 O 2 S: Calcd: C, 62.93; H, 8.70; N, 8.63; S, 9.88. Found: C, 62.66; H, 8.61; N, 8.49; S, 9.78.
EXAMPLE 13
5-[2-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]ethyl]-1,3,4-oxadiazol-2(3H)-one
A 12.5% solution of phosgene in toluene (5.5 mL, 6.2 mmol) is added dropwise to a -78° C. solution of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide (1.0 g, 2.94 mmol) in tetrahydrofuran (100 mL). The reaction mixture is stirred for 10 minutes then poured into a separatory funnel containing ethyl acetate and aqueous sodium bicarbonate. The organic phase is washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a heavy oil which is chromatographed on a 100 g column of silica with methanol/chloroform (3/97). After coevaporation with dichloromethane the product solidifies affording 0.64 g (63%) of 5-[2-[[3,5-bis-(1,1-dimethylethyl)-4-hydroxyphenyl]thio]ethyl]-1,3,4-oxadiazol-2(3H)-one, mp 86.0°-87.5° C.
Analysis for C 18 H 26 N 2 O 3 S: Calcd: C, 61.69; H, 7.48; N, 7.99; S, 9.15. Found: C, 61.51; H, 7.51; N, 7.85; S, 8.87.
EXAMPLE 14
5-[2-[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]ethyl-1,3,4-oxadiazole-2(3H)-thione
Thiophosgene (0.34 mL, 4.40 mmol) is added dropwise to a -78° C. solution of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide (1.5 g, 4.40 mmol) in tetrahydrofuran (150 mL). The reaction mixture is stirred for 10 minutes then poured into a separatory funnel containing ethyl acetate and aqueous sodium bicarbonate. The organic phase is washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a heavy oil which is crystallized from ethyl acetate/hexane to afford 1.0 g (59%) of 5-[2-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]ethyl]-1,3,4-oxadiazole-2(3H)-thione, mp 123.5°-124.5° C.
Analysis for C 18 H 26 N 2 O 2 S 2 : Calcd: C, 58.98; H, 7.15; N, 7.64; S, 17.50. Found: C, 59.08; H, 7.18; N, 7.53; S, 17.36.
EXAMPLE 5
2,6-Bis(1,1-dimethylethyl)-4-[2-(1,3,4-oxadiazol-2-yl)ethyl]thio]phenol
A catalytic amount of p-toluenesulfonic acid (25 mg) is added to a stirred solution of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide (0.50 g, 1.54 mmol) in triethyl orthoformate (10 mL). After 30 minutes, 10 mL of 1N hydrochloric acid is added and stirring is continued for 30 minutes. The reaction mixture is diluted with ethyl acetate and washed twice with a saturated solution of sodium bicarbonate, twice with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a crude product which is chromatographed on a column of silica with ethyl acetate/hexane (1/9 then 1/4) to afford 0.33 g (64%) of 2,6-bis(1,1-dimethylethyl)-4-[[2-(1,3,4-oxadiazol-2-yl)ethyl]thio]phenol, mp 87.5°-89.0° C.
Analysis for C 18 H 26 N 2 O 2 S: Calcd: C, 64.64; H, 7.83; N, 8.38; S, 9.59. Found: C, 64.50; H, 7.83; N, 8.24; S, 9.55.
EXAMPLE 16
4-[2-(5-Amino-1,3,4-oxadiazol-2-yl)ethyl]thio]-2,6-bis(1,1-dimethylethyl)phenol
A solution of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide (0.50 g, 1.54 mmol) in dioxane (15 mL) is added to a solution of sodium bicarbonate (0.14 g, 1.62 mmol) in water (4 mL). Cyanogen bromide (0.17 g, 1.62 mmol) is added in four equal portions at 1-minute intervals, and stirring is continued for 5 hours. The reaction mixture is diluted with ethyl acetate and sequentially washed with aqueous sodium bicarbonate, water, and brine. Drying the organic phase over magnesium sulfate and evaporation provides a solid which is crystallized from ethyl acetate/hexane to give 0.42 g (78%) of 4-[[2-(5-amino-1,3,4-oxadiazol-2-yl)ethyl]thio]-2,6-bis(1,1-dimethylethyl)phenol, mp 172.0°-174.0° C.
Analysis for C 18 H 27 N 3 O 2 S: Calcd: C, 61.86; H, 7.79; N, 12.02; S, 9.17. Found: C, 61.79; H, 7.66; N, 11.96; S, 9.10.
EXAMPLE 17
5-[2-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]-sulfinyl]ethyl]-1,3,4-oxadiazol-2(3H)-one
m-Chloroperbenzoic acid (1.30 g, 6.0 mmol) is added in eight portions at 5-minute intervals to a 0° C. solution of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide (2.25 g, 6.4 mmol) in dichloromethane (64 mL). The reaction mixture is stirred at 0° C. for 2.25 hours, then diluted with ethyl acetate and washed three times with a saturated solution of sodium bicarbonate, then with water and brine. Drying the organic phase over magnesium sulfate and evaporation gives a crude product which is chromatographed on a column of silica with ethyl acetate/hexane (3/1) to afford 1.92 g of a glassy solid.
EXAMPLE 18
5-[2-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]-sulfonyl]ethyl]-1,3,4-oxadiazol-2(3H)-one
m-Chloroperbenzoic acid (0.39 g, 1.83 mmol) is added in four portions at 5-minute intervals to a 0° C. solution of 5-[2-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylsulfinylethyl]-1,3,4-oxadiazol-2(3H)-one (0.50 g, 1.36 mmol) in dichloromethane (15 mL). The reaction mixture is stirred at 0° C. for an hour, then diluted with ethyl acetate and washed three times with a saturated solution of sodium bicarbonate, then with water followed by brine. Drying the organic phase over magnesium sulfate and evaporation gives a crude product which is chromatographed on a column of silica with ethyl acetate/hexane (1/1) to afford a foam which is crystallized from dichloromethane/hexane to give 0.42 g (81%) of 5-2-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]sulfonyl]ethyl]-1,3,4-oxadiazol-2(3H)-one, mp 161.5°-162.5° C.
Analysis for C 18 H 26 N 2 O 5 S: Calcd: C, 56.52; H, 6.85; N, 7.32; S, 8.38. Found: C, 56.24; H, 6.92; N, 7.23; S, 8.72.
EXAMPLE 19
3-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-propanoic acid 2-formylhydrazide
A solution of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid hydrazide (0.70 g, 2.16 mmol) in 96% formic acid (5.6 mL) is stirred overnight. The reaction mixture is concentrated in vacuo, diluted with ethyl acetate and washed once with a saturated solution of sodium bicarbonate, twice with water, and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives an oil which is crystallized from ethyl acetate/hexane to afford 0.68 g (89%) of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid 2-formylhydrazide, mp 158.0°-159.0° C.
Analysis for C 18 H 28 N 2 O 3 S: Calcd: C, 61.33; H, 8.01; N, 7.95; S, 9.10. Found: C,
61.35; H, 8.22; N, 7.86; S, 9.05.
EXAMPLE 20
2,6-Bis(1,1-dimethylethyl)-4-[[2-(1,3,4-thiadiazol-2-yl)ethyl]thio]-phenol
Phosphorous pentasulfide (0.28 g, 1.28 mmol) is added to a solution of 3-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]propanoic acid 2-formylhydrazide (0.45 g, 1.28 mmol) in dioxane (13 mL) and stirred overnight at 45° C. The reaction mixture is diluted with ethyl acetate and washed twice with 1N sodium hydroxide, three times with water, and twice with brine. Drying the organic phase over magnesium sulfate and evaporation gives an oil which is crystallized from methanol/water to afford 0.36 g (80%) of 2,6-bis(1,1-dimethylethyl)-4-[[2-(1,3,4-thiadiazol-2-yl)ethyl]thio]-phenol, mp 118.0°-120.0° C.
Analysis for C 18 H 26 N 2 OS 2 : Calcd: C, 61.67; H, 7.48; N, 7.99. Found: C, 61.35; H, 7.51; N, 7.79.
EXAMPLE 21
Methyl 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoate
Methyl 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoate is prepared according to the method of U.S. Pat. No. 4,659,863, assigned to the Ethyl Corporation, having as inventor Lester P. J. Burton.
EXAMPLE 22
3,5-Bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid hydrazide.
Hydrazine monohydrate (232 mL, 468 mmol) is added to a room temperature solution of methyl 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzene-propanoate (11.4 g, 39 mmol) in methanol (500 mL). The reaction mixture is heated at reflux for 2 hours, cooled, diluted with ethyl acetate and washed six times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation to 100 mL yields 9.25 g of colorless crystals. Further evaporation yields 0.84 g, therefore, providing a total of 10.09 g (88%) of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid hydrazide, mp 153.0°-154.5° C.
Analysis for C 17 H 28 N 2 O 2 : Calcd: C, 69.83; H, 9.65; N, 9.58. Found: C, 69.80; H, 9.80; N, 9.40.
EXAMPLE 23
5-[2-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethyl]-1,3,4-oxadiazol-2(3H)-one
A 12.5% solution of phosgene in toluene (10.7 mL, 12.0 mmol) is added dropwise to a -78° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid hydrazide in tetrahydrofuran (200 mL). The reaction mixture is stirred for 10 minutes then poured into a separatory funnel containing ethyl acetate and aqueous sodium bicarbonate. The organic phase is washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a crude product which is crystallized from hexane to afford 1.6 g (74%) of 5-[2-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethyl]-1,3,4-oxadiazol-2(3H)-one, mp 120.0°-123.0° C.
Analysis for C 18 H 26 N 2 O 3 : Calcd: C, 67.90; H, 8.23; N, 8.80. Found: C, 67.58; H, 8.17; N, 8.68.
EXAMPLE 24
5-[2-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethyl]-1,3,4-oxadiazole-2(3-thione
Thiophosgene (0.55 mL, 6.80 mmol) is added dropwise to a -78° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid hydrazide (2.0 g, 6.8 mmol) in tetrahydrofuran (200 mL). The reaction mixture is stirred for 10 minutes then poured into a separatory funnel containing ethyl acetate and aqueous sodium bicarbonate. The organic phase is washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a heavy oil which is crystallized from ethyl acetate/hexane. The product is chromatographed on a column of silica with ethyl acetate/dichloromethane (5/95) and recrystallized from dichloromethane/hexane to afford 0.36 g (16%) of 5-[2-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethyl]-1,3,4-oxadiazole-2(3H)-thione, mp 164.5°-165.5° C.
Analysis for C 18 H 26 N 2 O 2 S: Calcd: C, 64.64; H, 7.83; N, 8.38. Found: C, 64.43; H, 7.69; N, 8.47.
EXAMPLE 25
2,6-Bis(1,1-dimethylethyl)-4-[2-(1,3,4-oxadiazol-2-yl)ethyl]phenol
A catalytic amount of p-toluenesulfonic acid (25 mg) is added to a stirring solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid hydrazide (0.50 g, 1.71 mmol) in triethyl orthoformate (10 mL). After 30 minutes, 10 mL of 1N hydrochloric acid is added, and stirring is continued for 30 minutes. The reaction mixture is diluted with ethyl acetate and washed twice with a saturated solution of sodium bicarbonate, twice with water, and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a crude product which is chromatographed on a column of silica with ethyl acetate/hexane (1/9 then 1/4) to afford 0.34 g (67%) of 2,6-bis(1,1-dimethylethyl)-4-[2-(1,3,4-oxadiazol-2-yl)ethyl]phenol, mp 100.0°-101.0° C.
Analysis for C 18 H 26 N 2 O 2 : Calcd: C, 71.49; H, 8.66; N, 9.26. Found: C, 71.23; H, 8.53; N, 8.89.
EXAMPLE 26
4-[2-(5-Amino-1,3,4-oxadiazol-2-yl)ethyl]-2,6-bis(1,1-dimethylethyl)phenol
A solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid hydrazide (0.50 g, 1.71 mmol) in dioxane (15 mL) is added to a solution of sodium bicarbonate (0.16 g, 1.88 mmol) in water (4 mL). Cyanogen bromide (0.20 g, 1.88 mmol) is then added in 4 equal portions at 1-minute intervals, and stirring is continued for 5 hours. The reaction mixture is diluted with ethyl acetate and sequentially washed with aqueous sodium bicarbonate, water, and brine. Drying the organic phase over magnesium sulfate and evaporation provides a solid which is crystallized from ethyl acetate/hexane followed by methanol/water to give 0.32 g (59%) of 4-[2-(5-amino-1,3,4-oxadiazol-2-yl)ethyl]-2,6-bis(1,1-dimethylethyl)phenol, mp 220.0°-221.0° C.
Analysis for C 18 H 27 N 3 O 2 : Calcd: C, 68.11; H, 8.57; 3.24. Found: C, 67.93; H, 8.43; N, 13.18.
EXAMPLE 27
3,5-Bis(1,1-dimethylethyl)-4-hydroxy-α-oxo-benzeneacetic acid, methyl ester
A dichloromethane (50 mL) solution of 13.6 g (106.5 mmol, 1.1 equiv.) of methyloxalylchloride is added over 15 minutes to a 0° C. stirred slurry of 14.2 g (106.5 mmol, 1.1 equiv.) of AlCl 3 in 100 mL of dichloromethane under nitrogen atmosphere. The reaction is stirred at 0° C. for 5 minutes and treated with a dichloromethane (50 mL) solution of 20.0 g (96.9 mmol) of 2,6-di-t-butylphenol over 30 minutes. The reaction is stirred for 3 hours and poured onto 700 mL of ice water and the layers separated. The aqueous layer is extracted with diethyl ether (3×200 mL). The combined organic layers are washed with aqueous 1N HCl (200 mL), water (4×200 mL) and saturated aqueous NaCl, dried over Na 2 SO 4 and concentrated in vacuo to give a yellow solid. Recrystallizing from n-pentane gives a first crop of 8.40 g (mp 85°-86° C.) and a second crop of 4.45 g (mp 82.5°-84° C.). The total yield is 12.85 g (28.33 g theor., 45%).
Anal for C 17 H 24 O 4 : Calcd: C, 69.84; H, 8.27. Found: C, 69.83; H, 8.22.
EXAMPLE 28
3,5-Bis(1,1-dimethylethyl)-4-hydroxy-α-oxo-benzeneacetic acid
3,5-Bis(1,1-dimethylethyl)-4-hydroxy-α-oxo-benzeneacetic acid, methyl ester (20.0 g, 68.4 mmol) and LiOH (3.2 g, 439.1 mmol) are combined in 125 mL of a water-methanol-tetrahydrofuran mixture (1:1:1). The reaction warms to ca 50° C. and is maintained at this temperature using a heating bath for 5 hours under nitrogen atmosphere. The reaction is poured onto ice water and extracted with diethyl ether (3×). The cold aqueous layer is acidified with aqueous 12N HCl and extracted with diethyl ether (3×). The combined ethereal layers from the second extraction are washed with saturated aqueous NaCl, dried over Na 2 SO 4 , and concentrated in vacuo to give an oil. Crystallizing from diethyl ether/pentane gives 14.0 g of a first crop (mp 125°-126° C.) and 2.7 g as a second crop (mp 124°-125.5° C.). The total yield is 16.7 g (19.0 g theor., 88%).
EXAMPLE 29
(5-Amino- 1,3,4-thiadiazol-2-yl)[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]methanon
Step 1. A solution of 11.5 g (90.6 mmol, 1.5 equiv.) of oxalyl chloride in 20 mL of dichloromethane is added dropwise (15 minutes) to a 0° C. solution of 16.6 g (59.6 mmol) of 3,5-bis(1,1-dimethylethyl-4-hydroxy-α-oxo-benzeneacetic acid in 100 mL of dichloromethane and 3 drops of N,N-dimethylformamide under a nitrogen atmosphere. The reaction is stirred at 0° C. to room temperature for 1 hour and concentrated in vacuo to give the acid chloride as a yellow-orange solid.
Step 2. A slurry of 5.43 g (59.6 mmol) of thiosemicarbazide in 150 mL of tetrahydrofuran at 0° C. under nitrogen atmosphere is treated over 15 minutes with a solution of half the above acid chloride (ca 29.8 mmol) in 45 mL of tetrahydrofuran. The resulting reaction mixture is stirred at 0° C. to room temperature for 2 hours and poured onto 700 mL of cold aqueous 0.5N HCl. Extraction of the aqueous reaction with ethyl acetate (3×200 mL), washing of the combined organic layers with saturated aqueous NaCl, drying over Na 2 SO 4 , and concentration in vacuo gives a foam. The foam is dissolved in 200 mL of t-butylmethylether and a yellow solid immediately is formed to give 6.32 g of the hydrazide product.
Step 3. A 0° C. slurry of 6.32 g (˜15.0 mmol) of the above hydrazide in 75 mL of toluene is treated with 2.2 g (22.9 mmol) of methanesulfonic acid over 10 minutes. The reaction is warmed at 80° C. for 2 hours, cooled to room temperature, treated with water, and made basic (pH 8) with concentrated ammonium hydroxide. The mixture is extracted with dichloromethane (3×). The combined extracts were filtered, washed with saturated aqueous NaCl, and concentrated in vacuo to give an orange foam. Chromatography (flash, SiO 2 , 230-400 mesh, 15×6.5 cm, 50% ethyl acetate-hexane) gives an orange foam. Recrystallization from acetone-hexane gives 0.45 g (9.94 g theor., 4.5%) of desired product as a pale yellow solid.
Anal for C 17 H 23 N 3 O 2 S: Calcd: C, 61.23; H, 6.95; N, 12.60; S, 9.62. Found: C, 61.32; H, 7.12; N, 12.52; S, 9.47.
EXAMPLE 30
[3,5-Bis(1,1-dimethylethyl]-4-hydroxyphenyl][5-methylthio)-1,3,4-thiadiazol-2-yl]methanone
Step 1. The acid chloride of 3,5-bis(1,1-dimethylethyl)-4-hydroxy-α-oxobenzeneacetic acid (2.86 g, 10.27 mmol) is prepared in tetrahydrofuran as described in Step 1 of Example 29.
Step 2. The crude acid chloride is dissolved in 20 mL of tetrahydrofuran and treated dropwise with a tetrahydrofuran (10 mL) solution of 1.35 g (11.05 mmol, 1.08 equiv.) of hydrazinecarbodithioic acid, methyl ester (Audrieth, L. F., Scott, E. S., Kippur, P. S., J. Org. Chem. 1954, 19, 733).
The reaction is stirred for 3 hours, poured onto 200 mL of H 2 O, and extracted with diethyl ether (4×50 mL). The combined ethereal extracts are washed with saturated aqueous NaCl, dried over Na 2 SO 4 , and concentrated in vacuo to give a yellow foam.
Step 3. The foam is dissolved in 100 mL of toluene, treated with 0.5 g (2.63 mmol) of p-toluenesulfonic acid monohydrate, and warmed at 80° C. for 20 hours. The reaction is cooled to room temperature and concentrated in vacuo. The resulting residue is partitioned between water and ethyl acetate and the layers separated. The organic layer is washed with water and saturated aqueous NaCl, dried over Na 2 SO 4 , and concentrated in vacuo. Chromatography (SiO 2 , 70-230 mesh, 10%, 20%, 40% ethyl acetate-hexane step gradient, 20×4.5 cm) gives 1.78 g (3.74 g theor., 48%) of the desired product as a yellow solid after recrystallization from diethyl ether-hexane; mp 161.5°-162.5° C.
Analysis for C 18 H 24 N 2 O 2 S 2 : Calcd: C, 59.31; H, 6.64; N, 7.68. Found: C, 59.13; H, 6.62; N, 7.51.
EXAMPLE 31
[3,5-Bis(1,1-dimethylethyl)-4-hydroxphenyl][5(4H)-thioxo-1,3,4-thiadiazol-2-yl]methanone
Sodium thiomethoxide (0.45 g, 6.42 mmol, 2.17 equiv.) is added to a room temperature solution of 1.08 g (2.96 mmol) of [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl][5-(methylthio)-1,3,4-thiadiazol-2-yl]methanone in N,N-dimethylformamide (10 mL). The reaction becomes slightly warm and turns darker. The reaction is stirred at room temperature for 24 hours and warmed at 50° C. for 24 hours. The reaction is poured onto ice and aqueous 0.5N NaOH (100 mL) and extracted with t-butylmethylether (2×30 mL). The aqueous layer is acidified with aqueous 12N HCl to give a yellow solid. Recrystallization from toluene gives 0.84 g (1.04 theor., 81%) of the desired product as a yellow solid, mp 194°-201° C.
Anal. for C 17 H 22 N 2 O 2 S 2 : Calcd: C, 58.26; H, 6.33; N, 7.99. Found: C, 58,48; H, 6.38; N, 7.86.
EXAMPLE 32
2,6-Bis(1,1-dimethylethyl)-4-[2-[5-(methylthio)-1,3,4-thiadiazol-2-yl]ethyl]phenol
Potassium hydroxide (0.22 g, 3.3 mM) is added to a 0° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid hydrazide (1.0 g, 3.4 mM) and carbon disulfide (0.22 mL, 7.2 mM) in methanol (36 mL). The reaction mixture is stirred at 0° C. for 2 hours then at room temperature for 4 hours. Iodomethane (0.21 mL, 3.4 mM) is added and stirring is continued overnight. The reaction is diluted with ether and washed twice with water, once with a saturated solution of sodium bicarbonate, and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives 1.2 g of crude intermediate which is dissolved in toluene (20 mL). p-Toluenesulfonic acid (0.72 g, 3.8 mM) is added to the solution and the reaction is heated at reflux for 1.5 hours. The reaction solution is cooled and filtered. The filtrate is diluted with ether and washed twice with water, once with a saturated solution of sodium bicarbonate, and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a crude product which is chromatographed on silica gel eluting with 1:9 then 2:8 ethyl acetate:hexane yielding 0.29 g (25%) of a white solid which is 2,6-bis(1,1-dimethylethyl)-4-[2-[5-(methylthio)-1,3,4-thiadiazol-2-yl]ethyl]phenol; mp 135°-139° C.
EXAMPLE 33
5-[2-3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethyl]-1,3,4-thiadiazole-2(3H)-thione
Sodium thiomethoxide (0.10 g, 1.35 mM) is added to a solution of 2,6-bis(1,1-dimethylethyl)-4-[2-[5-(methythio)-1,3,4-thiadiazol-2-yl]ethyl]phenol (0.10 g, 0.27 mM) in dimethylformamide (2.7 mL). The reaction solution is heated at 80° C. for 4 hours then cooled, diluted with ethyl acetate and washed once with 1N hydrochloric acid, three times with water, and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives 0.10 g of a white solid which is recrystallized from ethyl acetate/hexane yielding 0.08 g (84%) of colorless crystals which is 5-[2-[3,5bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethyl]-1,3,4-thiadiazole-2(3H)-thione; mp 213.0°-214.0° C.
Analysis for C 18 H 26 N 2 OS 2 : Calcd: C, 61.67; H, 7.48; N, 7.99. Found: C, 61.77; H, 7.40; N, 8.03.
EXAMPLE 34
5-[2-[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethyl]-1,3,4-thiadiazol-2(3H)-one
Two equal portions of 80% m-chloroperbenzoic acid (0.10 g, 0.48 mM) are added to a 0° C. solution of 2,6-bis(1,1-dimethylethyl)-4-[2-[5-(methylthio)-1,3,4-thiadiazol-2-yl]ethyl]phenol (0.86 g, 0.24 mM) in methylene chloride (4 mL) at 30 minute intervals. The reaction is allowed to warm slowly to room temperature and another portion of 80% m-chloroperbenzoic acid (0.05 g, 0.24 mM) is added. The reaction solution is stirred for 5 hours then diluted with ethyl acetate and washed five times with a saturated solution of sodium bicarbonate, once with water, and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives 0.13 g of a brown oil which is dissolved in dioxane (2 mL). An aqueous solution of 50% sodium hydroxide (0.16 g, 2.0 mM) diluted with water (0.7 mL) is added and stirring is continued for 6 hours at room temperature. The dark red reaction solution is diluted with ethyl acetate and washed once with 1N hydrochloric acid, twice with water, and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a brown solid which is chromatographed on silica gel eluting with 2:8 ethyl acetate:hexane followed by crystallization from ethyl acetate/hexane yielding 0.03 g (37) of pale yellow crystals which are 5-[2-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]ethyl]-1,3,4-thiadiazol-2(3H)-one; mp 149.5°-151.0° C.
Analysis for C 18 H 26 N 2 O 2 S: Calcd: C, 64.64; H, 7.84; N, 8.38. Found: C, 64.54; H, 7.79; N, 8.00.
EXAMPLE 35
2,6-Bis(1,1-dimethylethyl]-4-[[5-(methylthio)-1,3,4-thiadiazol-2-yl]thio]phenol
A solution of 4-bromo-2,6-di-t-butylphenol (3.0 g, 10.5 mmol), 5-methylthio-1,3,4-thiadiazole-2-thiol (2.0 g, 12.2 mmol), and 1,8-diazabicyclo-[5.4.0]undecen-7-ene (1.8 mL, 12.0 mmol) in dimethylformamide (120 mL) is stirred at 55° to 70° C. for 48 hours. The reaction mixture is cooled and diluted with ether then washed four times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a solid residue which is crystallized from ethyl acetate/hexane yielding 2.4 g (63%) of analytically pure light brown platelets; mp 144.0°-145.0° C. The mother liquor is chromatographed on silica gel eluting with 1:9 then 2:8 ethyl acetate:hexane to yield an additional 0.7 g (18%) of 2,6-bis(1,1-dimethylethyl)-4-[[5-(methylthio)-1,3,4-thiadiazol-2-yl]thio]phenol.
Analysis for C 17 H 24 N 2 OS 3 : Calcd: C, 55.40; H, 6.56; N, 7.60; S, 26.10. Found: C, 55.64; H, 6.47; N, 7.56; S, 25.80.
EXAMPLE 36
2,6-Bis(1,1-dimethylethyl)-4-5-(methylsulfinyl)-1,3,4-thiadiazol-2-yl]thio]phenol
A solution of 2,6-bis(1,1-dimethylethyl)-4-[[5-(methylthio)-1,3,4-thiadiazol-2-yl]thio]phenol (0.25 g, 0.68 mmol) and sodium perborate (0.11 g, 0.71 mmol) in acetic acid (20 mL) is stirred at room temperature for 7 hours then stored at 0° C. overnight. The reaction mixture is diluted with ether and washed three times with water, then with a saturated solution of sodium bicarbonate and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a white solid which is chromatographed on silica gel eluting with a gradient of ethyl acetate:hexane (1:9, 2:8, 3:7, then 1:1) yielding 0.16 g (61%) of 2,6-bis(1,1-dimethylethyl)-4-[[5-(methylsulfinyl)-1,3,4-thiadiazol-2-yl]thio]-phenol; mp 162.0°-163.5° C.
Analysis for C 17 H 24 N 2 O 2 S 3 : Calcd: C, 53.09; H, 6.29; N, 7.28. Found: C, 53.47; H, 6.23; N, 7.36.
EXAMPLE 37
[5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-thiadiazol-2-yl]cyanamide
Cyanamide (0.11 g, 2.60 mmol) is added to a suspension of potassium t-butoxide (0.26 g, 2.27 mmol) in t-butanol (6.5 mL) and stirred at room temperature for 30 minutes. 2,6-Bis(1,1-dimethylethyl)-4-[[5-(methylsulfinyl)-1,3,4-thiadiazol-2-yl]thio]phenol (0.25 g, 0.65 mmol) is added and stirring is continued at 55° C. for 2 hours. The reaction mixture is diluted with ethyl acetate and washed with dilute aqueous hydrochloric acid, then three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives an oil which is dissolved in acetonitrile and concentrated slowly in vacuo yielding 0.15 g (64%) of yellow crystals which are [5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-thiadiazol-2-yl]cyanamide.
Analysis for C 17 H 2 N 4 OS 2 : Calcd: C, 56.33; H, 6.12; N, 15.45; S, 17.69. Found: C, 56.16; H, 6.12; N, 15.55; S, 18.04.
EXAMPLE 38
N-[5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-thiadiazol-2-yl]guanidine
Guanidine hydrochloride (0.24 g, 2.60 mmol) is added to a suspension of potassium t-butoxide (0.26 g, 2.27 mmol) in t-butanol (6.5 mL) and stirred at room temperature for 30 minutes. 2,6-Bis(1,1-dimethylethyl)-4-[[5-(methylsulfinyl)-1,3,4-thiadiazol-2-yl]thio]phenol (0.25 g, 0.65 mmol) is added and stirring is continued at 55° C. for 4 hours then at 70° C. for 2.5 hours. The reaction mixture is diluted with ethyl acetate and water. The aqueous phase is neutralized with 1N hydrochloric acid and discarded. The organic phase is washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a light brown oil which is dissolved in acetonitrile and evaporated to a semi-solid. The material is suspended in ether and filtered to give 0.10 g (39%) of light brown crystals which are N-[5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]thio]-1,3,4-thiadiazol-2-yl]guanidine; mp 248.0°-249.0° C.
Analysis for C 17 H 25 N 5 OS 2 : Calcd: C, 53.80; H, 6.64; N, 18.45. Found: C, 53.69; H, 6.60; N, 18.82.
EXAMPLE 39
2,6-Di-t-butyl-1,4-dihydroquinone
Prepared according to the method of Matti Karhu; J. Chem. Soc., Perkin Trans. I; 303, 1981.
EXAMPLE 40
3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenyl carbonothioic acid hydrazide
A solution of 2,6-di-butyl-1,4-dihydroquinone (2.0 g, 9.0 mmol) and N,N-diisopropylethylamine (2.3 mL, 13.5 mmol) in toluene (50 mL) is added to a 0° C. solution of thiophosgene (1.0 mL, 13.5 mmol) in toluene (40 mL). The reaction mixture is stirred for 30 minutes at 0° C. and hydrazine monohydrate (4.4 mL, 90.0 mmol) is added. The ice bath is removed and the reaction is stirred for 2 hours. The reaction mixture is diluted with ether and washed four times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a brown oil which is chromatographed on silica gel eluting with 2:8 then 4:6 ethyl acetate:hexane yielding 1.9 g (72%) of a light brown solid. An analytical sample is obtained by crystallization from ether/hexane to give light brown crystals of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl carbonothioic acid hydrazide; mp 102°-106° C.
Analysis for C 15 H 24 N 2 O 2 S: Calcd: C, 60.78; H, 8.16; N, 9.45; S, 10.82. Found: C, 60.80: H, 7.97: N, 9.30: S, 10.70
EXAMPLE 41
5-[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-1,3,4-thiadiazol-2(3H)-one
A 12.5% solution of phosgene in toluene (1.27 mL, 1.42 mmol) is added dropwise to a -78° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl carbonothioic acid hydrazide (0.20 g, 0.67 mmol) in tetrahydrofuran (15 mL). The reaction mixture is stirred for 30 minutes, diluted with ethyl acetate, and washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and coevaporation with ether/hexane gives a solid which is crystallized from ether/hexane to give 0.14 g (62%) of pale yellow crystals which are 5-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-1,3,4-thiadiazol-2(3H)-one; mp 184.5°-188.0° C.
Analysis for C 16 H 22 N 2 O 3 S: Calcd: C, 59.60; H, 6.88; N, 8.69; S, 9.94. Found: C, 59.22; H, 6.55; N, 8.56; S, 9.87.
EXAMPLE 42
5-[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-1,3,4-thiadiazol-2(3H)-thione
Thiophosgene (57 μL, 0.74 mmol) is added dropwise to a -78° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl carbonothioic acid hydrazide (0.20 g, 0.67 mmol) in tetrahydrofuran (15 mL). The reaction mixture is stirred for 30 minutes, diluted with ethyl acetate, and washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and coevaporation with ether/hexane gives a solid which is crystallized from methylene chloride/hexane to give 0.18 g (80%) of a pale yellow powder which is 5-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-1,3,4-thiadiazol-2(3H)-thione; mp 181°-186° C.
Analysis: C 16 H 22 N 2 O 2 S 2 : Calcd: C, 56.77; H, 6.55; N, 8.28; S, 18.95. Found: C, 56.91; H, 6.56; N, 7.98; S, 19.07.
EXAMPLE 43
2,6-Bis(1,1-dimethylethyl)-4-[[5-(methylthio)-1,3,4-thiadiazol-2-yl]oxy]phenol
A solution of 1N sodium hydroxide (2.95 mL, 2.95 mmol) is added dropwise to a solution of 5-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-1,3,4-thiadiazole-2(3H)-thione (1.00 g, 2.95 mmol) and iodomethane (0.74 mL, 11.8 mmol) in methanol (30 mL). The reaction solution is diluted with ether and washed once with dilute aqueous hydrochloric acid, three times with water, and once with brine. Drying the organic phase over magnesium sulfate and evaporation followed by crystallization from hexane gives 0.83 g (80%) of tan crystals which are 2,6-bis(1,1-dimethylethyl)-4-[[5-(methylthio)-1,3,4-thiadiazol-2-yl]oxy]phenol; mp 132.0°-134.0° C.
Analysis for C 17 H 24 N 2 O 2 S 2 : Calcd: C, 57.92; H, 6.86; N, 7.95. Found: C, 58.01; H, 6.47; N, 8.03.
EXAMPLE 44
2,6-Bis(1,1-dimethylethyl)-4-[[5-(methylsulfonyl)-1,3,4-thiadiazol-2-yl]oxy]phenol
Three equal portions of 80% m-chloroperbenzoic acid (1.3 g, 6.0 mmol) are added to a -10° C. solution of 2,6-bis(1,1-dimethylethyl)-4-[[5-(methylthio)-1,3,4-thiadiazol-2-yl]oxy]phenol (0.70 g, 2.0 mmol) in methylene chloride (20 mL) at 30-minute intervals. Stirring is continued for 1 hour at -10° C. then at room temperature for 2 hours. The reaction solution is diluted with ether and washed three times with a saturated solution of sodium bicarbonate, once with water, and once with brine. Drying over magnesium sulfate and evaporation followed by crystallization from ether/hexane yields 0.72 g (94%) of pale yellow crystals which are 2,6-bis(1,1-dimethylethyl)-4-[[5-(methylsulfonyl)-1,3,4-thiadiazol-2-yl]oxy]phenol; mp 174.5°-175.5° C.
Analysis for C 17 H 24 N 2 O 4 S 2 : Calcd: C, 53.10; H, 6.29; N, 7.29. Found: C, 53.00; H, 6.26; N, 7.31.
EXAMPLE 45
Ethyl [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]acetate
A mixture of 2,6-di-t-butyl-1,4-dihydroquinone (5.0 g, 22.5 mmol), ethyl bromoacetate (5.0 mL, 45.0 mmol), and powdered potassium carbonate (9.3 g, 67.5 mmol) in freshly distilled tetrahydrofuran (100 mL) is stirred vigorously at a gentle reflux for 26 hours. The reaction mixture is poured into water and acidified with 6N hydrochloric acid. The aqueous phase is extracted twice with ether. The combined organic phase is washed twice with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives an oil which is chromatographed on silica gel eluting with 2:98 then 5:95 ethyl acetate:hexane. The resulting heavy oil crystallizes to give 5.2 g (75%) of ethyl [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxyacetate. An analytically pure sample is obtained by recrystallization from ethanol/water; mp 54.5°-56.0° C.
Analysis for C 18 H 28 O 4 : Calcd: C, 70.10; H, 9.15. Found C, 69.99; H, 9.07.
EXAMPLE 46
[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenoxy]acetic acid hydrazide
A solution of ethyl [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]acetate (2.5 g, 8.1 mmol) and hydrazine monohydrate (1.2 mL, 24.3 mmol) in ethanol (40 mL) is heated at 65°-75° C. for 8 hours. The reaction mixture is cooled and poured into 500 mL of water. The solids are filtered and washed twice with water. The white solid is dried overnight at 50° C. in vacuo to give 2.1 g (87%) of [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-acetic acid hydrazide; mp 141.0°-142.5° C.
Analysis for C 16 H 26 N 2 O 3 : Calcd: C, 65.28; H, 8.90; N, 9.52. Found: C, 65.62; H, 8.99; N, 9.23.
EXAMPLE 47
4-(5-Amino-1,3,4-oxadiazol-2-yl)methoxy]-2,6-bis-(1,1-dimethylethyl)phenol
A solution of [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-acetic acid hydrazide (0.15 g, 0.52 mmol) in dioxane (5 mL) is added to a solution of sodium carbonate (0.04 g, 0.52 mmol) in water (1.2 mL). After stirring 10 minutes, cyanogen bromide (0.06 g, 0.52 mmol) is added and stirring is continued for 4 hours. The reaction solution is diluted with ethyl acetate and washed twice with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a crude residue which is chromatographed on silica gel eluting with 3:7 ethyl acetate:methylene chloride yielding 0.14 g (84%) of 4-[(5-amino-1,3,4-oxadiazol-2-yl)methoxy]-2,6-bis(1,1-dimethylethyl)phenol; mp 177.5°-180.0° C.
Analysis for C 17 H 25 N 3 O 3 : Calcd: C, 63.93; H, 7.89; N, 13.15. Found: C, 63.71; H, 7.81; N, 13.18.
EXAMPLE 48
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-methyl]-1,3,4-oxadiazol-2(3H)-one
A 12.5% solution of phosgene in toluene (2.4 mL, 2.7 mmol) is added dropwise to a -78° C. of [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-acetic acid hydrazide (0.40 g, 1.36 mmol) in tetrahydrofuran (25 mL). The reaction mixture is stirred for 30 minutes, diluted with ethyl acetate, and washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a pale yellow oil which is crystallized from ethyl acetate/hexane yielding 0.34 g (79%) of 5-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]methyl-1,3,4-oxadiazol-2(3H)-one; mp 138.0°-140.0° C.
Analysis for C 17 H 24 N 2 O 4 : Calcd: C, 63.73; H, 7.55; N, 8.74. Found: C, 63.99; H, 7.49; N, 8.62.
EXAMPLE 49
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-methyl]-1,3,4-oxadiazole-2(3H)-thione
Thiophosgene (0.10 mL, 1.36 mmol) is added dropwise to a -78° C. solution of [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy-acetic acid hydrazide (0.40 g, 1.36 mmol) in tetrahydrofuran (25 mL). The reaction mixture is stirred for 30 minutes, diluted with ethyl acetate, and washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a pale yellow oil which is crystallized from ethyl acetate/hexane yielding 0.36 g (78%) of 5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxymethyl]-1,3,4-oxadiazole-2(3H)-thione, mp 195.0°-196.5° C.
Analysis for C 17 H 24 N 2 O 3 S: Calcd: C, 60.68; H, 7.19; N, 8.32; S, 9.53. Found: C, 60.86; H, 7.05; N, 7.96; S, 9.14.
EXAMPLE 50
[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenoxy]acetonitrile
A mixture of 2,6-di-t-butyl-1,4-dihydroquinone (3.5 g, 15.6 mmol), bromoacetonitrile (5.4 mL, 77.8 mmol), and powdered potassium carbonate (6.4 g, 46.7 mmol) in freshly distilled tetrahydrofuran (70 mL) is stirred vigorously at a gentle reflux for 72 hours. An additional amount of bromoacetonitrile (4.0 mL, 57.6 mM) is added and stirring is continued at reflux for 24 hours. The reaction mixture is cooled and diluted with ether and ethyl acetate and filtered. The filtrate is washed three times with water, once with 1N hydrochloric acid, twice with dilute aqueous sodium hydroxide, twice with water, and once with brine. Drying the organic phase with magnesium sulfate and evaporation gives an oil which is chromatographed on silica gel yielding 2.0 g (50%) of a pale yellow oil which is [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy] acetonitrile. A small portion is purified by Kugelrohr distillation.
Analysis for C 16 H 23 NO 2 : Calcd: C, 73.53; H, 8.87; N, 5.36. Found: C, 73.66; H, 8.94; N, 5.17.
EXAMPLE 51
2-[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenoxy]ethanethioamide
Hydrogen sulfide gas is bubbled for 30 minutes into a solution of [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy] acetonitrile (1.16 g, 4.44 mmol) and triethylamine (0.68 mL, 4.88 mmol) in pyridine (4.5 mL). The reaction mixture is diluted with ether and washed once with dilute aqueous hydrochloric acid, three times with water, and once with brine. The organic phase is dried over magnesium sulfate and filtered. Argon is bubbled through the organic solution to remove residual hydrogen sulfide. The organic phase is concentrated in vacuo and the solid residue is crystallized from ether/hexane yielding 1.1 g (82%) of white crystals of 2-[3,5-bis((1,1-dimethylethyl)-4-hydroxyphenoxy]-ethanethioamide; mp 163.0°-164.0° C.
Analysis for C 16 H 25 NO 2 S: Calcd: C, 65.05; H, 8.53; N, 4.74; S, 10.85. Found: C, 64.95; H, 8.18; N, 4.77; S, 11.08.
EXAMPLE 52
5-[[3,5-Bis(1,1-dimethylethyl)-4-hydroxyphenoxy]methyl]-1,3,4-thiadiazole-2(3H)-thione
Hydrazine monohydrate (0.18 mL, 3.72 mmol) is added to a solution of 2-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-ethanethioamide (1.10 g, 3.72 mmol) in methanol (37 mL). After stirring for 1 hour an additional amount of hydrazine monohydrate (0.18 mL, 3.73 mmol) is added and stirring is continued for 1 hour. The reaction mixture is diluted with ether and washed four times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives 1.16 g of a pale yellow foam which is dissolved in methanol (40 mL). To this solution is added carbon disulfide (2.4 mL, 39.7 mmol) and stirring is continued overnight. The reaction solution is diluted with ether and washed three times with water and once with brine. Drying the organic phase over magnesium sulfate and evaporation gives a solid which is crystallized from ether/hexane, followed by methanol/water, and then chromatographed on silica gel eluting with 2:3:15 acetone:methylene chloride:hexane yielding 0.14 g (10%) of a white powder which is 5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]methyl]-1,3,4-thiadiazole-2(3H)-thione; mp 192°-195° C.
Analysis for C 17 H 24 N 2 O 2 S 2 : Calcd: C, 57.92; H, 6.86; N, 7.95. Found: C, 58.12; H, 6.95; N, 7.82.
EXAMPLE 53
2,6-Bis(1,1-dimethylethyl)-4-[(5-methylthio-1,3,4-thiadiazol-2-yl)methoxy]phenol
A solution of 1N sodium hydroxide (1.05 mL, 1.05 mmol) is added over 5 minutes to a solution of 5-[[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenoxy]-methyl]-1,3,4-thiadiazole-2(3H)-thione (0.37 g, 1.05 mmol) and iodomethane (0.26 mL, 4.20 mmol) in methanol (10 mL). The reaction is stirred for 30 minutes, then the pink precipitate is filtered and washed with methanol/water. A second crop is collected, and the combined precipitate is (71%) of pink platelets which are 2,6-bis(1,1-dimethylethyl)-4-[(5-methylthio-1,3,4-thiadiazol-2-yl)methoxy]phenol; mp 128.0°-129.5° C.
Analysis for C 18 H 26 N 2 O 2 S 2 : Calcd: C, 58.98; H, 7.15; N, 7.64. Found: C, 59.08; H, 7.48; N, 7.65.
EXAMPLE 54
5-(Methylsulfonyl)-1,3,4-thiadiazole-2-carboxylic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxylphenyl ester and [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl][5-(methylsulfonyl)-1,3,4-thiadiazole-2-yl]-methanone.
A 0° C. solution of 10.0 g (27.4 mmol) of [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]-[5-methylthio)-1,3,4-thiadiazol-2-yl]methanone in 160 mL of CH 2 Cl 2 under N 2 atmosphere is treated with 18.0 g (83-89 mmol) of 80°-85° m-chloroperbenzoic acid in small portions over 30 minutes. The reaction is slowly allowed to warm to 25° C. The reaction is stirred for a total of 23 hours and partitioned between t-butylmethylether and aqueous 5% M NaHCO 3 . The layers are separated and the organic layer is washed with aqueous 5% M NaHCO 3 (3×) and saturated aqueous NaCl (1×), dried over Na 2 SO 4 and concentrated in vacuo to give a yellow solid. Recrystallization from t-butylmethylether/hexane gave 1.82 g (16%) of analytically pure 5-(methylsulfonyl)-1,3,4-thiadiazole-2-carboxylic acid, 3,5-bis(1,1-methylethyl)-4-hydroxyphenyl ester as a yellow solid; mp 164.5°-165.5° C. A second crop of 4.5 g (41%) of analytically pure 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl][5-(methylsulfonyl)-1,3,4-thiadiazol-2-yl]methanone is isolated as a dark yellow solid; mp 197°-199° C.
EXAMPLE 55
N-[5-[3,5-Bis(1,1-dimethylethyl)-4-hydroxybenzoyl-1,3,4-thiadiazol-2-yl]guanidine
A slurry of 0.47 g (4.92 mmol) of guanidine hydrochloride in t-BuOH under N 2 atmosphere is treated with 4.5 mL (4.5 mmol) of a 1.0M KOtBu/t-BuOH solution. The resulting mixture is treated with 1.00 g (2.52 mmol) of [3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl][5-methylsulfonyl)-1,3,4-thiadiazol-2-yl]methanone and warmed at 90° C. for 2 hours, The reaction is poured onto 75 mL of H 2 O and 50 mL of ethyl acetate. The layers are separated and the aqueous layer is extracted with ethyl acetate (2×40 mL). The combined organic layers are washed with saturated aqueous NaCl, dried over Na 2 SO 4 , and concentrated in vacuo. Chromatography (SiO 2 , 70-230 mesh, ethyl acetate eluant, 3.5×18 cm) gives a solid. Recrystallization from methanol-water gives 0.37 g (mp 267°-269° C.) of analytically pure material as a first crop and 0.13 g (mp 262°-264° C.) of a second crop also analytically pure which is N-[5-[3,5-bis(1,1-dimethylethyl)-4-hydroxybenzoyl]-1,3,4-thiadiazol-2-yl]guanidine. | The novel 3,5-ditertiarybutyl-4-hydroxyphenylthio-1,3,4-thiadiazoles and oxadiazoles and 3,5-ditertiarybutyl-4-hydroxyphenylmethanone-1,3,4-thiadiazoles and oxadiazoles and related compounds of the present invention are antiinflammatory agents having activity as inhibitors of 5-lipoxygenase, cyclooxygenase or both. | 2 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority from and the benefit of U.S. Provisional Patent Application Ser. No. 61/528,956 filed on 30 Aug. 2011 and United Kingdom Patent Application No. 1114734.5 filed on 25 Aug. 2011. The entire contents of these applications are incorporated herein by reference.
[0002] The present invention relates to a mass or mass to charge ratio selective ion trap. The preferred embodiment relates to ion guiding and trapping systems and methodology for use in mass spectrometry systems.
BACKGROUND ART
[0003] It is well known that the time averaged force on a charged particle or ion due to an AC inhomogeneous electric field is such as to accelerate the charged particle or ion to a region where the electric field is weaker. A minimum in the electric field is commonly referred to as a pseudo-potential well or valley. Correspondingly, a maximum is commonly referred to as a pseudo-potential hill or barrier.
[0004] Paul traps, also known as 3D ion traps, are designed to exploit this phenomenon by causing a pseudo-potential well to be formed in the centre of the ion trap. The pseudo-potential well is then used to confine a population of ions. Due to its symmetric nature the 3D ion trap acts to confine ions to a single point in space as shown in FIG. 1A . However, the mutual repulsion between ions of identical polarity in addition to the non-zero kinetic energy of the confined ions lead to the ions occupying a spherical volume at the centre of the ion trap as illustrated in FIG. 1B .
[0005] There is a finite space charge capacity for any ion confining device beyond which its performance begins to degrade and where ultimately the device cannot hold any further charges. For example, overfilling an ion trap leads to a loss of mass resolution and of mass accuracy, a result of the electric field becoming distorted by the presence of the large number of charges being focused into close proximity. It is generally the case that the space charge limit for storage of ions is significantly greater than the spectral or analytical space charge limit which is the maximum number of ions which can be confined whilst retaining a given mass resolution and mass accuracy.
[0006] For mass spectrometry applications it is necessary to detect the mass to charge ratio (m/z) of the confined ions. For example, ions may be ejected in a mass selective manner towards an ion detector (although many other detection methods exist). There are several known methods of ejecting ions either resonantly or non-resonantly to achieve this goal.
[0007] It is often necessary to introduce gas into ion trapping devices. The gas may be used for cooling purposes or ion fragmentation via Collision Induced Decomposition (“CID”). Ion Mobility Separation (“IMS”) has also been performed either with a static volume of gas or with a flow of gas. The use of pulsed gas valves to introduce gas into ion traps is also known.
[0008] Recently, there has been increased interest in 2D or Linear Ion Traps (“LIT”) because of the increased volume which the confined ions are able to occupy. Linear ion traps allow a greater number of ions, or more correctly a greater number of charges, to be confined and then detected. Such ion traps are generally based on multipolar RF ion guides such as quadrupoles, hexapoles or octopoles. A pseudo-potential well is formed within the rod set ion trap around the central axis of the ion guide so that ions are confined radially within the ion trap. The ions are normally confined axially using DC fields although methods of using RF fields to axially confine ions are also known.
[0009] The radial pseudo potential of a 2D ion trap acts to focus the confined ions to a line through the central axis of the ion trap as shown in FIG. 1C . In a similar manner to 3D ion traps, ions confined within a 2D ion trap will in practice be spatially distributed and thus occupy an elongated cylindrical volume as shown in FIG. 1D .
[0010] Ion ejection has been demonstrated both radially and axially using 2D ion traps by resonantly exciting the ions within the confining radial pseudo potential. Radial ejection has been achieved by allowing the ions to resonate until their radial excursions reach the quadrupole electrodes at which point they pass through narrow slots in the electrodes. Axial ejection has been achieved by resonantly exciting the ions into the naturally occurring fringing fields which exist at the exit of a quadrupole at which point it is possible for the ions to gain sufficient axial kinetic energy to overcome the confining DC barrier. Both of these methods are inherently non-adiabatic in nature and lead to large ejection energies and large energy spreads which makes them generally unsuitable for coupling with other devices such as other mass analysers.
[0011] Another form of axial ejection from a 2D ion trap is known and comprises superimposing an axial harmonic DC potential upon a radial confining RF of an ion guide. Such approaches are schematically represented in FIGS. 2A-C .
[0012] FIG. 2A shows a 2D ion trap comprising a series of annular electrodes which coaxially encompass a quadrupole rod set. RF voltages are applied to the rod set electrodes in order to cause ions to be radially confined. DC voltages are applied to the annular electrodes to produce an axial DC potential within the rod set.
[0013] FIG. 2B shows a 2D ion trap comprising an RF quadrupole rod set with additional vane electrodes placed on the ground planes which are used to provide an axial DC potential.
[0014] FIG. 2C shows a 2D ion trap comprising an axially segmented RF quadrupole rod set. Different DC voltages may be applied to each segment in order to provide an axial DC potential.
[0015] With respect to the 2D ion traps shown in FIGS. 2A-2C , the DC potential which is applied in the axial (z) direction is given by Eqn. 1:
[0000] U z ( t )=( a+b .cos(Ω t )). z 2 (1)
[0000] where b is the electric field constant of the axial quadratic potential, a is the amplitude and Ω is the frequency of the modulation of the axial potential.
[0000]
E
z
=
U
z
(
t
)
z
=
2
(
a
+
b
·
cos
(
Ω
t
)
)
·
z
(
2
)
z
¨
+
ω
2
z
=
F
·
cos
(
Ω
t
)
ω
=
2
aq
m
and
F
=
2
bq
m
(
3
)
z
(
t
)
=
F
ω
2
-
Ω
2
sin
(
Ω
t
+
φ
)
(
4
)
SUMMARY OF THE INVENTION
[0016] According to an aspect of the present invention there is provided a mass or mass to charge ratio selective ion trap comprising:
[0017] a first device arranged and adapted to generate a radially asymmetric pseudo-potential barrier or well which acts to confine ions in a first (y) and a second (x) direction within the ion trap;
[0018] a second device arranged and adapted to generate a substantially DC quadratic potential well which acts to confine ions in a third (z) direction within the ion trap, wherein the profile of the substantially quadratic DC potential well progressively varies along the second (x) direction; and
[0019] a third device arranged and adapted to excite ions in the third (z) direction so as to mass or mass to charge ratio selectively eject ions in the second (x) direction and/or in the third (z) direction.
[0020] According to an aspect of the present invention there is provided a mass or mass to charge ratio selective ion trap comprising:
[0021] a first device arranged and adapted to generate a pseudo-potential barrier or well which acts to confine ions in a first (y) direction and a DC potential barrier or well which acts to confine ions in a second (x) direction within the ion trap;
[0022] a second device arranged and adapted to generate a substantially DC quadratic potential well which acts to confine ions in a third (z) direction within the ion trap, wherein the profile of the substantially quadratic DC potential well progressively varies along the second (x) direction; and
[0023] a third device arranged and adapted to excite ions in the third (z) direction so as to mass or mass to charge ratio selectively eject ions in the second (x) direction and/or in the third (z) direction.
[0024] The first (y) direction and/or the second (x) direction and/or the third (z) direction are preferably substantially orthogonal.
[0025] According to an embodiment the mass or mass to charge ratio selective ion trap comprises a plurality of electrodes.
[0026] The plurality of electrodes preferably comprise:
[0027] (i) a multipole rod set or a segmented multipole rod set comprising a plurality of or at least 4, 5, 6, 7, 8, 9, 10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-100 or >100 rod sets or segmented rod sets; and/or
[0028] (ii) an ion tunnel or ion funnel comprising a plurality of or at least 4, 5, 6, 7, 8, 9, 10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-100 or >100 annular, ring or oval electrodes having one or more apertures through which ions are transmitted in use; and/or
[0029] (iii) a plurality of or at least 4, 5, 6, 7, 8, 9, 10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-100 or >100 half annular, half ring, half oval or C-shaped electrodes; and/or
[0030] (iv) a stack or array of planar, plate or mesh electrodes arranged generally in the plane in which ions travel in use.
[0031] The first device is preferably arranged and adapted to apply an RF voltage to at least some of the electrodes.
[0032] The ion trap is preferably arranged and adapted so that there is a full and/or direct line of sight through the ion trap in the third (z) direction.
[0033] The ion trap is preferably arranged and adapted so that there is a full and/or direct line of sight through the ion trap in the second (x) direction.
[0034] The second device is preferably arranged and adapted to form the substantially quadratic DC potential well so that either: (i) a minimum of the substantially quadratic DC potential well is along a central axis of the ion trap; or (ii) a minimum of the substantially quadratic DC potential well is offset from a central axis of the ion trap.
[0035] The pseudo-potential barrier or well preferably comprises a non-quadrupolar pseudo-potential barrier or well.
[0036] The third device is preferably arranged and adapted to cause ions to oscillate in the third (z) direction, and the amplitude of oscillation of the ions in the third (z) direction is preferably dependent on the mass or mass to charge ratio of the ions.
[0037] An electric field is preferably maintained along the second (x) direction.
[0038] The electric field preferably progressively increases, decreases or varies along the second (x) direction.
[0039] The electric field preferably urges, channels or directs ions towards an ion ejection region of the ion trap. Ions are preferably mass or mass to charge ratio selectively ejected in the second (x) direction and/or in the third (z) direction from the ion ejection region.
[0040] The magnitude of the electric field in the second (x) direction preferably increases, decreases or varies with position in the third (z) direction.
[0041] The electric field preferably causes ions to experience substantially different acceleration fields in the second (x) direction dependent upon the relative position of the ions in the third (z) direction.
[0042] The electric field preferably urges ions having a particular mass or mass to charge ratio or ions having a mass or mass to charge ratio within a particular range in the second (x) direction prior to the ions being mass or mass to charge ratio selectively ejected in the third (z) direction.
[0043] The electric field preferably urges ions in the second (x) direction with a force dependent on the amplitude of oscillation of the ions in the third (z) direction prior to the ions being mass or mass to charge ratio selectively ejected in the second (x) direction and/or in the third (z) direction.
[0044] Ions are preferably confined in the third (z) direction by the DC quadratic potential well and the height of at least one side of the well preferably decreases with position in the second (x) direction towards the ejection region such that ions having an amplitude of oscillation in the third (z) direction are confined by the ion trap in a region away from the ejection region in the second (x) direction, whereas ions in the ejection region having the same amplitude of oscillation in the third (z) direction are able to surmount the DC potential well and are ejected from the ion trap.
[0045] The second device is preferably arranged and adapted to maintain the substantially DC quadratic potential well across some but not all electrodes arranged in the third (z) direction.
[0046] The second device is preferably arranged and adapted to maintain a substantially DC quadratic potential well across x % of the width of the ion trap in the third (z) direction, wherein x is selected from the group consisting of: (i) <10; (ii) 10-20; (iii) 20-30; (iv) 30-40; (v) 40-50; (vi) 50-60; (vii) 60-70; (viii) 70-80; (ix) 80-90; (x) 90-95; and (xi) 95-99.
[0047] The second device is preferably arranged and adapted to maintain a DC potential profile in the third (z) direction across the ion trap wherein the DC potential profile comprises a first region and one or more second regions, wherein the DC potential profile in the first region is substantially quadratic and wherein the DC potential profile in the one or more second regions is substantially linear, constant or non-quadratic.
[0048] The second device is preferably arranged and adapted to maintain a DC potential profile in the third (z) direction which is asymmetric preferably about a central axis of the ion trap, wherein the central axis is preferably in the second (x) direction.
[0049] The second device is preferably arranged and adapted to maintain a DC potential profile in the third (z) direction which results in ions being ejected from the substantially DC quadratic well in one direction only.
[0050] The third device is preferably arranged and adapted so that ions are mass or mass selectively ejected from the an trap either: (i) in a first direction only or (ii) both in a first direction and a second direction, wherein the second direction is different to or opposed to the first direction.
[0051] The third device is preferably arranged and adapted to excite ions resonantly in the third (z) direction.
[0052] The third device is preferably arranged and adapted to apply a supplemental AC voltage or potential to at least some of the electrodes having a frequency σ which is equal to ω, wherein ω is the fundamental or resonance frequency of ions which are desired to be ejected from the ion trap.
[0053] The third device is preferably arranged and adapted to excite ions parametrically in the third (z) direction.
[0054] The third device is preferably arranged and adapted to apply a supplemental AC voltage or potential to at least some of the electrodes having a frequency σ equal to 2ω, 0.667ω, 0.5ω, 0.4ω, 0.33ω, 0.286ω, 0.25ω or <0.25ω, wherein ω is the fundamental or resonance frequency of ions which are desired to be ejected from the ion trap.
[0055] The third device is preferably arranged and adapted to scan, vary, alter, increase, progressively increase, decrease or progressively decrease the frequency σ of the supplemental AC voltage or potential.
[0056] The third device is preferably arranged and adapted: (i) in a mode of operation to eject ions from the ion trap in order of their mass to charge ratio; and/or (ii) in a mode of operation to eject ions from the ion trap in reverse order of their mass to charge ratio.
[0057] The third device is preferably arranged and adapted to cause ions to be ejected from the ion trap in a substantially adiabatic manner.
[0058] The third device is preferably arranged and adapted to cause ions to be ejected from the ion trap with an ion energy selected from the group consisting of: (i) <0.5 eV; (ii) 0.5-1.0 eV; (iii) 1.0-1.5 eV; (iv) 1.5-2.0 eV; (v) 2.0-2.5 eV; (vi) 2.5-3.0 eV; (vii) 3.0-3.5 eV; (viii) 3.5-4.0 eV; (ix) 4.0 eV-4.5 eV; (x) 4.5-5.0 eV; and (xi) >5.0 eV.
[0059] The ion trap is preferably arranged and adapted to contain N ion charges within the ion trap, wherein N is selected from the group consisting of: (i) <5×10 4 ; (ii) 5×10 4 -1×10 5 ; (iii) 1×10 5 -2×10 5 ; (iv) 2×10 5 -3×10 6 ; (v) 3×10 5 -4×10 5 ; (vi) 4×10 5 -5×10 5 ; (vii) 5×10 5 -6×10 5 ; (viii) 6×10 5 -7×10 5 ; (ix) 7×10 5 -8×10 5 ; (x) 8×10 5 -9×10 5 ; (xi) 9×10 5 -1×10 6 ; and (xii) >1×10 6 .
[0060] In a mode of operation at least a region or substantially the whole of the ion trap is preferably arranged and adapted to be operated:
[0061] (i) as an ion guide; and/or
[0062] (ii) as a collision or fragmentation cell; and/or
[0063] (iii) as a reaction cell; and/or
[0064] (ii) as a mass filter; and/or
[0065] (iii) as a time of flight separator; and/or
[0066] (iv) as an ion mobility separator; and/or
[0067] (v) as a differential ion mobility separator.
[0068] In a mode of operation the ion trap is preferably arranged and adapted to be maintained at a pressure selected from the group consisting of: (i) <1.0×10 −7 mbar; (ii) 1.0×10 −7 -1.0×10 −6 mbar; (iii) 1.0×10 −5 -1.0×10 −5 mbar; (iv) 1.0×10 −5 -1.0×10 −4 mbar; (v) 1.0×10 −4 -1.0×10 −3 mbar; (vi) 0.001-0.01 mbar; (vii) 0.01-0.1 mbar; (viii) 0.1-1 mbar; (ix) 1-10 mbar; (x) 10-100 mbar; and (xi) 100-1000 mbar.
[0069] According to an aspect of the present invention there is provided a mass spectrometer comprising a mass or mass to charge ratio selective ion trap as described above.
[0070] According to an aspect of the present invention there is provided a method of mass or mass to charge ratio selective ejection of ions from an ion trap comprising:
[0071] generating a radially asymmetric pseudo-potential barrier or well which acts to confine ions in a first (y) and a second (x) direction within the ion trap;
[0072] generating a substantially DC quadratic potential well which acts to confine ions in a third (z) direction within the ion trap, wherein the profile of the substantially quadratic DC potential well progressively varies along the second (x) direction; and
[0073] exciting ions in the third (z) direction so as to mass or mass to charge ratio selectively eject ions in the second (x) direction and/or in the third (z) direction.
[0074] According to an aspect of the present invention there is provided a method of mass or mass to charge ratio selective ejection of ions from an ion trap comprising:
[0075] generating a pseudo-potential barrier or well which acts to confine ions in a first (y) direction and a DC potential barrier or well which acts to confine ions in a second (x) direction within the ion trap;
[0076] generating a substantially DC quadratic potential well which acts to confine ions in a third (z) direction within the ion trap, wherein the profile of the substantially quadratic DC potential well progressively varies along the second (x) direction; and
[0077] exciting ions in the third (z) direction so as to mass or mass to charge ratio selectively eject ions from the ion trap in the second (x) direction and/or in the third (z) direction.
[0078] According to an aspect of the present invention there is provided a method of mass spectrometry comprising a method as described above.
[0079] According to an aspect of the present invention there is provided an ion trap with a trapping volume which is spatially extended in two spatial dimensions from which ions of a chosen mass to charge ratio are moved from the whole volume into a smaller ejection region prior to their ejection from the ion trap.
[0080] Despite the larger ion capacity of 2D ion traps over 3D ion traps, the need for ion traps with increased ion capacity grows as instruments become more sensitive and ion sources become brighter.
[0081] The preferred embodiment comprises an ion trap or ion transmission device with an enlarged trapping or transmitting volume. According to an embodiment the ion trap comprises a 1D ion trap which is arranged to confine and eject ions and which has a greater ion charge capacity than conventional 3D and 2D ion traps.
[0082] In the same way that a 3D ion trap fundamentally confines ions to a point and a 2D ion trap fundamentally confines ions to a line, the 1D ion trap according to the preferred embodiment fundamentally confines ions to a plane as shown in FIG. 1E . However, in practice the actual volume occupied by the ions will expand to fill a rectangular prism which is elongated in two spatial dimensions as shown in FIG. 1F .
[0083] An ion trap according to a preferred embodiment of the present invention comprises an array of electrodes which define an extended volume to which various combinations of RF, AC and DC voltages may be applied. The ion trap may act as either an ion transmission device or as an ion trap. The ion trap may be used to hold, accumulate, store, process, isolate, fragment, detect and eject ions. In operation some or all of the ions are distributed within the extended trapping region and may be moved in a mass to charge ratio dependent manner towards a specific region of the ion trap from which they may be subsequently ejected. Ion ejection is preferably effected by exciting the ions within a substantially DC quadratic potential. The form of the quadratic potential varies along the length of the device such that it is steeper in some regions and shallower in other regions. The act of exciting the ion leads to the ions being squeezed from the steeper regions into the shallower regions from where the ions are finally ejected.
[0084] The ion trap may be operated as a mass analyser or may be used in conjunction with a mass analyser or other devices within a mass spectrometer.
[0085] According to an embodiment the mass, spectrometer may further comprise:
[0086] (a) an ion source selected from the group consisting of: (i) an Electrospray ionisation (“ESI”) ion source; (ii) an Atmospheric Pressure Photo Ionisation (“APPI”) ion source; (iii) an Atmospheric Pressure Chemical Ionisation (“APCI”) ion source; (iv) a Matrix Assisted Laser Desorption Ionisation (“MALDI”) ion source; (v) a Laser Desorption Ionisation (“LDI”) ion source; (vi) an Atmospheric Pressure Ionisation (“API”) ion source; (vii) a Desorption Ionisation on Silicon (“DIOS”) ion source; (viii) an Electron Impact (“EI”) ion source; (ix) a Chemical Ionisation (“CI”) ion source; (x) a Field Ionisation (“FI”) ion source; (xi) a Field Desorption (“FD”) ion source; (xii) an Inductively Coupled Plasma (“ICP”) ion source; (xiii) a Fast Atom Bombardment (“FAB”) ion source; (xiv) a Liquid Secondary Ion Mass Spectrometry (“LSIMS”) ion source; (xv) a Desorption Electrospray Ionisation (“DESI”) ion source; (xvi) a Nickel-63 radioactive ion source; (xvii) an Atmospheric Pressure Matrix Assisted Laser Desorption Ionisation ion source; (xviii) a Thermospray ion source; (xix) an Atmospheric Sampling Glow Discharge Ionisation (“ASGDI”) ion source; and (xx) a Glow Discharge (“GD”) ion source; and/or
[0087] (b) one or more continuous or pulsed ion sources; and/or
[0088] (c) one or more ion guides; and/or
[0089] (d) one or more ion mobility separation devices and/or one or more Field Asymmetric Ion Mobility Spectrometer devices; and/or
[0090] (e) one or more ion traps or one or more ion trapping regions; and/or
[0091] (f) one or more collision, fragmentation or reaction cells selected from the group consisting of: (i) a Collisional Induced Dissociation (“CID”) fragmentation device; (ii) a Surface Induced Dissociation (“SID”) fragmentation device; (iii) an Electron Transfer Dissociation (“ETD”) fragmentation device; (iv) an Electron Capture Dissociation (“ECD”) fragmentation device; (v) an Electron Collision or Impact Dissociation fragmentation device; (vi) a Photo Induced Dissociation (“PID”) fragmentation device; (vii) a Laser Induced Dissociation fragmentation device; (viii) an infrared radiation induced dissociation device; (ix) an ultraviolet radiation induced dissociation device; (x) a nozzle-skimmer interface fragmentation device; (xi) an in-source fragmentation device; (xii) an in-source Collision Induced Dissociation fragmentation device; (xiii) a thermal or temperature source fragmentation device; (xiv) an electric field induced fragmentation device; (xv) a magnetic field induced fragmentation device; (xvi) an enzyme digestion or enzyme degradation fragmentation device; (xvii) an ion-ion reaction fragmentation device; (xviii) an ion-molecule reaction fragmentation device; (xix) an ion-atom reaction fragmentation device; (xx) an ion-metastable ion reaction fragmentation device; (xxi) an ion-metastable molecule reaction fragmentation device; (xxii) an ion-metastable atom reaction fragmentation device; (xxiii) an ion-ion reaction device for reacting ions to form adduct or product ions; (xxiv) an ion-molecule reaction device for reacting ions to form adduct or product ions; (xxv) an ion-atom reaction device for reacting ions to form adduct or product ions; (xxvi) an ion-metastable ion reaction device for reacting ions to form adduct or productions; (xxvi) an ion-metastable molecule reaction device for reacting ions to form adduct or product ions; (xxviii) an ion-metastable atom reaction device for reacting ions to form adduct or product ions; and (xxix) an Electron Ionisation Dissociation (“EID”) fragmentation device; and/or
[0092] (g) a mass analyser selected from the group consisting of: (i) a quadrupole mass analyser; (ii) a 2D or linear quadrupole mass analyser; (iii) a Paul or 3D quadrupole mass analyser; (iv) a Penning trap mass analyser; (v) an ion trap mass analyser; (vi) a magnetic sector mass analyser; (vii) Ion Cyclotron Resonance (“ICR”) mass analyser; (viii) a Fourier Transform Ion Cyclotron Resonance (“FTICR”) mass analyser; (ix) an electrostatic or orbitrap mass analyser; (x) a Fourier Transform electrostatic or orbitrap mass analyser; (xi) a Fourier Transform mass analyser; (xii) a Time of Flight mass analyser; (xiii) an orthogonal acceleration Time of Flight mass analyser; and (xiv) a linear acceleration Time of Flight mass analyser; and/or
[0093] (h) one or more energy analysers or electrostatic energy analysers; and/or
[0094] (i) one or more ion detectors; and/or
[0095] (j) one or more mass filters selected from the group consisting of: (i) a quadrupole mass filter; (ii) a 2D or linear quadrupole ion trap; (iii) a Paul or 3D quadrupole ion trap; (iv) a Penning ion trap; (v) an ion trap; (vi) a magnetic sector mass filter; (vii) a Time of Flight mass filter; and (viii) a Wein filter; and/or
[0096] (k) a device or ion gate for pulsing ions; and/or
[0097] (l) a device for converting a substantially continuous ion beam into a pulsed ion beam.
[0098] The mass spectrometer may further comprise either:
[0099] (i) a C-trap and an Orbitrap® mass analyser comprising an outer barrel-like electrode and a coaxial inner spindle-like electrode, wherein in a first mode of operation ions are transmitted to the C-trap and are then injected into the Orbitrap® mass analyser and wherein in a second mode of operation ions are transmitted to the C-trap and then to a collision cell or Electron Transfer Dissociation device wherein at least some ions are fragmented into fragment ions, and wherein the fragment ions are then transmitted to the C-trap before being injected into the Orbitrap® mass analyser; and/or
[0100] (ii) a stacked ring ion guide comprising a plurality of electrodes each having an aperture through which ions are transmitted in use and wherein the spacing of the electrodes increases along the length of the ion path, and wherein the apertures in the electrodes in an upstream section of the ion guide have a first diameter and wherein the apertures in the electrodes in a downstream section of the ion guide have a second diameter which is smaller than the first diameter, and wherein opposite phases of an AC or RF voltage are applied, in use, to successive electrodes.
[0101] An RF voltage is preferably applied to the electrodes of the preferred ion trap and preferably has an amplitude selected from the group consisting of: (i) <50 V peak to peak; (ii) 50-100 V peak to peak; (iii) 100-150 V peak to peak; (iv) 150-200 V peak to peak; (v) 200-250 V peak to peak; (vi) 250-300 V peak to peak; (vii) 300-350 V peak to peak; (viii) 350-400 V peak to peak; (ix) 400-450 V peak to peak; (x) 450-500 V peak to peak; (xi) 500-550 V peak to peak; (xxii) 550-600 V peak to peak; (xxiii) 600-650 V peak to peak; (xxiv) 650-700 V peak to peak; (xxv) 700-750 V peak to peak; (xxvi) 750-800 V peak to peak; (xxvii) 800-850 V peak to peak; (xxviii) 850-900 V peak to peak; (xxix) 900-950 V peak to peak; (xxx) 950-1000 V peak to peak; and (xxxi) >1000 V peak to peak.
[0102] The RF voltage preferably has a frequency selected from the group consisting of: (i) <100 kHz; (ii) 100-200 kHz; (iii) 200-300 kHz; (iv) 300-400 kHz; (v) 400-500 kHz; (vi) 0.5-1.0 MHz; (vii) 1.0-1.5 MHz; (viii) 1.5-2.0 MHz; (ix) 2.0-2.5 MHz; (x) 2.5-3.0 MHz; (xi) 3.0-3.5 MHz; (xii) 3.5-4.0 MHz; (xiii) 4.0-4.5 MHz; (xiv) 4.5-5.0 MHz; (xv) 5.0-5.5 MHz; (xvi) 5.5-6.0 MHz; (xvii) 6.0-6.5 MHz; (xviii) 6.5-7.0 MHz; (xix) 7.0-7.5 MHz; (xx) 7.5-8.0 MHz; (xxi) 8.0-8.5 MHz; (xxii) 8.5-9.0 MHz; (xxiii) 9.0-9.5 MHz; (xxiv) 9.5-10.0 MHz; and (xxv) >10.0 MHz.
[0103] The ion trap is preferably maintained at a pressure selected from the group comprising: (i) >0.001 mbar; (ii) >0.01 mbar; (iii) >0.1 mbar; (iv) >1 mbar; (v) >10 mbar; (vi) >100 mbar; (vii) 0.001-0.01 mbar; (viii) 0.01-0.1 mbar; (ix) 0.1-1 mbar; (x) 1-10 mbar; and (xi) 10-100 mbar.
BRIEF DESCRIPTION OF THE DRAWINGS
[0104] Various embodiments of the present invention together with other arrangements given for illustrative purposes only will now be described, by way of example only, and with reference to the accompanying drawings in which:
[0105] FIG. 1A shows the volume occupied by ions in theory in a 3D ion trap, FIG. 1B shows the volume occupied by ions in practice in a 3D trap, FIG. 1C shows the volume occupied by ions in theory in a 2D ion trap, FIG. 1D shows the volume occupied by ions in practice in a 2D ion trap, FIG. 1E shows the volume occupied by ions in theory in a 1D ion trap according to an embodiment of the present invention and FIG. 1F shows the volume occupied by ions in practice in a 1D ion trap according to an embodiment of the present invention;
[0106] FIG. 2A shows a known linear or 2D ion trap comprising a plurality of annular electrodes surrounding a quadrupole rod set, FIG. 2B shows a known linear or 2D ion trap comprising a quadrupole rod set with vane electrodes and FIG. 2C shows a known linear or 2D ion trap comprising a segmented quadrupole rod set;
[0107] FIG. 3A shows an ion trap according to a preferred embodiment of the present invention, FIG. 3B shows an end on view of the preferred ion trap and FIG. 3C shows a side view of the preferred ion trap;
[0108] FIG. 4A shows how ions may be confined in the x-direction within the preferred ion trap by applying a DC voltage to end pairs of electrodes, FIG. 4B shows how ions may be confined in the x-direction within the preferred ion trap by applying a DC voltage to additional end plate electrodes and FIG. 4C shows how ions may by confined in the x-direction within the preferred ion trap by applying a RF voltage to additional rod electrodes;
[0109] FIG. 5A shows how according to a preferred embodiment the DC potential applied to three groups of electrodes varies along the x-direction, FIG. 5B shows how the DC potential varies in the z-direction and FIG. 5C shows a 3D representation of the DC potential in the x-z plane;
[0110] FIG. 6A shows a mode of operation wherein an ion channel is formed in the preferred ion trap and FIG. 6B shows a preferred embodiment of the present invention wherein ions are mass to charge ratio selectively urged in the x-direction and are then mass to charge ratio selectively ejected from the ion trap in the z-direction;
[0111] FIG. 7A shows the result of a SIMION® simulation modeling the ejection of ions from a preferred ion trap wherein the effects of space charge were not included and FIG. 7B shows the result of a SIMION® simulation when the effects of space charge were included;
[0112] FIG. 8 shows an embodiment wherein the preferred ion trap is integrated with a Stacked Ring Ion Guide (“SRIG”) collision cell; and
[0113] FIG. 9A shows an embodiment wherein a source of ions is followed by a preferred ion trap, a quadrupole and an ion detector, FIG. 9B shows an embodiment wherein a source of ions is followed by a quadrupole, a collision cell, a preferred ion trap, a further quadrupole and an ion detector, FIG. 9C shows an embodiment wherein a source of ions is followed by a preferred ion trap, a quadrupole, a collision cell, a further quadrupole and an ion detector and FIG. 9D shows an embodiment wherein a source of ions is followed by a preferred ion trap, a quadrupole, a collision cell and a Time of Flight mass analyser.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0114] An ion trap according to a preferred embodiment of the present invention is shown in FIG. 3A . The ion trap consists of an extended three dimensional array of electrodes 301 . According to an embodiment the electrodes comprise segmented rod electrodes.
[0115] The ion trap can be considered as comprising two horizontal layers of electrodes. Ions are confined in the vertical (y) direction (i.e. between the two horizontal layers of electrodes) by applying an RF voltage to the electrodes. Ions are confined in the vertical (y) direction by a non-quadrupolar pseudo-potential.
[0116] FIG. 3B shows an end on view of the segmented rod electrodes. According to the preferred embodiment all the segmented electrodes which conceptually form a rod are preferably maintained at the same phase of the RF voltage. Horizontally adjacent segmented rod electrodes are preferably maintained at opposite RF phases. Segmented rod electrodes in the upper layer are preferably maintained at the same RF phase as corresponding segmented rod electrodes in the lower layer.
[0117] With reference to FIG. 3B , ion confinement in the x-z plane is preferably achieved by applying opposite phases of a RF voltage 303 to adjacent rows of electrodes in the x direction.
[0118] FIG. 3C shows a side view of the electrode positions to aid in the visualisation of the entire structure.
[0119] A quadratic DC potential is preferably maintained in the z-direction by applying a quadratic DC potential to the electrodes in the z-direction. As a result, ions are preferably confined in an ion volume 302 which is shown in FIG. 3A as a rectangular prism.
[0120] Ions may initially enter the ion trap in the z-direction and then the quadratic DC potential may be applied to the electrodes in the z-direction. Alternatively, the quadratic DC potential may be applied to the electrodes in the z-direction and ions may enter the ion trap in the x-direction.
[0121] With reference to FIGS. 4A-4C a number of different techniques may be used to confine ions axially within the ion trap in the x-direction.
[0122] FIG. 4A shows a preferred embodiment of the present invention wherein ions are confined axially within the ion trap in the x-direction by applying a supplemental DC potential 401 to the end or outermost pairs of electrodes in the y-z plane. According to this embodiment ions may enter the ion trap initially in either the x- or z-directions.
[0123] FIG. 4B shows an alternative embodiment wherein a DC potential may be applied to additional end plate electrodes 402 . According to this embodiment ions initially enter the ion trap via the z-direction. Once ions have entered the ion trap a quadratic potential is then preferably maintained in the z-direction.
[0124] FIG. 4C shows another alternative embodiment wherein additional segmented or non-segmented rod set electrodes 403 are provided. The RF voltage applied to the segmented rod set electrodes 301 is also preferably applied to the additional electrodes 403 so that ions are confined axially in the x-direction within the ion trap by a pseudo-potential barrier or well. According to this embodiment ions initially enter the ion trap via the z-direction. Once ions have entered the ion trap a quadratic potential is then preferably maintained in the z-direction.
[0125] According to a preferred embodiment a DC quadratic potential is preferably superimposed on the RF voltages applied to the electrodes in the z-direction such that a DC potential well is formed in the z-direction as shown in FIG. 3C . The DC quadratic potential may be applied to electrodes so that a quadratic potential well is maintained in the z-direction before or after ions have entered the ion trap.
[0126] The form of the quadratic potential or DC potential well in the z-direction preferably varies across or along the length of the ion trap.
[0127] An example of how the quadratic potential may vary across or along the length of the ion trap will now be described in further detail with reference to FIGS. 5A-C .
[0128] FIG. 5A shows a plot of the applied potential along the three lines of electrodes labelled 304 , 305 , 306 in FIG. 3A wherein the three lines of electrodes have different displacements in the z-direction. It is apparent from FIG. 5A that the electrodes 304 arranged towards the centre of the ion trap have a low or zero potential gradient in the z-direction whereas the electrodes 306 arranged furthermost from the centre of the ion trap have a high potential gradient. The effect is to provide an electric field which funnels or directs ions towards the centre of the ion trap in the z-direction and which also directs ions towards one end of the ion trap having a displacement of zero in the x-direction. The magnitude of the electric field in the x-direction preferably varies with position in the z-direction, so that the electric field preferably causes ions to experience substantially different acceleration fields in the x-direction dependent upon the relative position of the ions in the z-direction.
[0129] FIG. 5B shows a plot of the applied potential along the three lines of electrodes labelled 307 , 308 , 309 in FIG. 3A wherein the three lines of electrodes 307 , 308 , 309 have different displacements in the x-direction The electrodes 307 having a displacement closest to zero in the x-direction have a shallow quadratic potential maintained across them in the z-direction whereas the electrodes 309 arranged with the maximum displacement in the x-direction have a deep quadratic potential maintained across them in the z-direction.
[0130] FIG. 5C shows a 3D plot of the applied potential to aid the visualisation of the applied potential.
[0131] Embodiments of the present invention are contemplated wherein ions are mass or mass to charge ratio selectively ejected from the preferred ion trap in the z-direction in one direction only. In alternative embodiments, ions are mass or mass to charge ratio selectively ejected from the preferred ion trap in the x-direction only or in both the x-direction and in the z-direction. According to an embodiment the quadratic potential which is maintained in the z-direction may be asymmetric in the sense that a quadratic potential may be maintained across a majority of the electrodes but some of the electrodes on one side of the ion trap may be maintained at a constant potential. As a result, a quadratic potential may be maintained which is effectively truncated on one side of the potential well in the z-direction. It will be apparent, therefore, that the maximum potential on one side of the potential well may be greater than the maximum potential on the other side of the potential well.
[0132] An ion trap according to the preferred embodiment may be used in several different modes of operation.
[0133] In a mode of operation the ion trap may be used as an ion transmission device and/or as a collision cell. This may be achieved by applying appropriate DC potentials to the electrodes so that one or more ion transmission channels exist through which ions may pass. FIG. 6A shows an embodiment wherein the ion trap is operated as an ion guide and/or as a collision cell.
[0134] FIG. 6B shows a preferred embodiment wherein ions are ejected from the ion trap in the z-direction. DC quadratic potentials are preferably applied to the electrodes in the z-direction in the manner as shown and described above in relation to FIG. 5 .
[0135] An AC or tickling voltage is preferably applied to the electrodes in order to resonantly excite the ions within the ion trap. Application of the AC or tickling voltage preferably causes ions to oscillate in the z-direction. The amplitude of oscillation of the ions in the z-direction is preferably dependent on the mass or mass to charge ratio of the ions. As discussed above, the electric field causes ions to experience substantially different acceleration fields in the x-direction dependent upon the relative position of the ions in the z-direction. Thus, the electric field urges ions in the x-direction with a force dependent on the amplitude of oscillation of the ions in the z-direction, which in turn depends on the mass or mass to charge ratio of the ions.
[0136] Thus, the application of the AC or tickling voltage in combination with the electric field preferably results in ions being pushed in a mass to charge ratio dependent manner from within the bulk of the ion trap towards one region of the ion trap (i.e. towards the left hand side of the ion trap in the x-direction as shown in FIG. 6B ). The ion trap is preferably arranged such that ions cannot be ejected from anywhere except from the specified ion ejection region. Ions are preferably confined in the z-direction by the DC quadratic potential well and the height of at least one side of the well decreases with position in the x-direction towards the ejection region such that ions having an amplitude of oscillation in the z-direction are confined by the ion trap in a region away from the ejection region in the x-direction, whereas ions in the ejection region having the same amplitude of oscillation in the z-direction are able to surmount the DC potential well and are ejected from the ion trap. Ions ejected from the ion trap may be detected directly or else may be passed to further RF devices and/or mass analysers for further processing or detection.
[0137] The preferred ion trap has been modeled using the ion optical modeling package SIMION®. FIG. 7A shows a plot of the ejection time of ions from the preferred ion trap for three groups of ions which were modeled as having mass to charge ratios of 400, 450 and 500 Da. Space charge effects were neglected in this instance. It is apparent that ions having a mass to charge ratios of 400 were initially ejected, followed by ions having a mass to charge ratio of 450 followed by ions having a mass to charge ratio of 500.
[0138] Identical simulations were also performed wherein approximately 1×10 6 charges were included within the ion trap to ascertain the effect of a very large space charge within the ion trap. By way of comparison it is known that the performance of conventional 3D ion traps becomes degraded when the number of charges within the ion trap is of the order of 1×10 3 . The equivalent number for 2D or linear traps has previously been determined to be of the order of 5×10 4 .
[0139] FIG. 7B shows the ejection times for the SIMION® simulations where space charge effects were included. Neither the peak ejection times nor the peak widths (and hence the resolution of the ion trap) were unduly affected due to the presence of such a large amount of space charge.
[0140] Accordingly, as will be apparent from comparing FIGS. 7A and 7B , the preferred ion trap having an extended ion confinement volume is particularly advantageous compared to conventional 2D and 3D ion traps.
[0141] FIG. 8 shows another embodiment of the present invention wherein a preferred ion trap is integrated with a Stacked Ring Ion Guide (“SRIG”) collision cell. The stacked ring ion guide preferably contains argon gas for good fragmentation efficiency whereas the preferred ion trap preferably contains helium gas for good ejection efficiency. The collision cell and ion trap may be used in tandem as a single ion transmission and/or collision cell.
[0142] Alternatively, the collision cell and ion trap may be used separately i.e. the collision cell may be used to fragment and/or accumulate ions and the ion trap may be used to hold and eject ions accumulated in the stacked ring ion guide.
[0143] FIGS. 9A-D show examples of instrument geometries according to various embodiments of the present invention. It will be apparent to those skilled in the art that there are many more potential configurations beyond these examples.
[0144] FIG. 9A shows an embodiment wherein a source of ions is followed by an ion trap according to the preferred embodiment followed by a quadrupole followed by an ion detector.
[0145] FIG. 9B shows an embodiment comprising a source of ions followed by a quadrupole, followed by a collision cell, followed by an ion trap according to the preferred embodiment, followed by a second quadrupole and an ion detector.
[0146] FIG. 9C shows an embodiment comprising a source of ions followed by an ion trap according to a preferred embodiment, followed by a quadrupole, followed by a collision cell, followed by a second quadrupole and an ion detector.
[0147] FIG. 9D shows an embodiment comprising a source of ions followed by an ion trap according to a preferred embodiment, followed by a quadrupole, followed by a collision cell and a Time of Flight mass analyser.
[0148] It will be apparent that various modifications may be made to the particular embodiments discussed above without departing from the scope of the invention.
[0149] For example, embodiments are contemplated wherein the electrodes comprising the ion trap may comprise electrodes which are not rod shaped. For example, the electrodes may comprise a plurality of stacked plate electrodes, a plurality of stacked ring electrodes, a plurality of half ring electrodes of a plurality of C-shaped electrodes.
[0150] According to a less preferred embodiment the applied DC potential may be non-quadratic.
[0151] According to an embodiment, the DC potential well may be deeper on one side of the ion trap than on the other side of the ion trap. As a result, ions are preferably ejected in one direction rather than being ejected in two directions.
[0152] According to an embodiment, the direction of exit of ions from the ion trap may be changed by changing the depth of the DC well appropriately such that all or a selection of ions preferably exit one way or all or a selection of ions preferably exit the other way.
[0153] According to an embodiment, the ion trap may be operated in a linked scanning mode of operation with the mass to charge ratio ejection of ions from the DC well linked with the m/z scan of an adjacent mass analyser.
[0154] According to an embodiment, there may be more than one ejection region.
[0155] According to an embodiment, ions may be injected in one place and either ejected from the same location or from another spatially distinct region.
[0156] According to an embodiment more than one ion compression region may be provided i.e. ions may be stored in wings and then moved in an mass to charge ratio manner into a central ejection region.
[0157] Although the present invention has been described with reference to preferred embodiments, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the invention as set forth in the accompanying claims. | A mass or mass to charge ratio selective ion trap is disclosed which directs ions into a small ejection region. A RF voltage acts to confine ions in a first (y) direction within the ion trap. A DC or RF voltage acts to confine ions in a second (x) direction. A quadratic DC potential well acts to confine ions in a third (z) direction within the ion trap. The profile of the quadratic DC potential well progressively varies along the second (x) direction. | 7 |
CROSS SECTION TO RELATED APPLICATION
This application claims priority under 35 U.S.C. §119 to Chinese Patent Application Ser. No. 2006.2011.2698.7, filed May 9, 2006, entitled, HOSE/CABLE REELER.
TECHNICAL FIELD
This invention relates to a hose (or cable) reeler used to store up hoses, cables or the like, and particularly to a treadle hose/cable reeler that achieves the retraction of hoses or cables using manpower, such as treading of a foot.
BACKGROUND ART
In the prior art hose/cable reelers used to store up hoses, cables or the like, the retraction of hoses or the like is achieved purely relying on a coil spring mounted inside the reeler. With the prior equipment, there are some problems as follows: the cost of the equipment is increased due to the need for a retracting coil spring; since the retraction is achieved by the coil spring, the retraction speed of the hose may be too fast and therefore during the retraction of the hose a brandish of the hose may occur, which may cause harms to people or damages to the hoses or cables; and once the coil spring fails, its maintenance or replacement is time-consuming and laborious.
SUMMARY OF THE INVENTION
It is an objective of this invention is to solve the above problems in the prior art. This invention aims to provide a hose/cable reeler which achieves the hose retraction without the need for a retracting coil spring, and therefore avoids the problems associated with the use of the retracting coil spring. In this invention, a coil spring is provided only as an auxiliary unit and has two functions: one is to increase the retractive force during the retraction of hoses or cables, and the other is to keep the continuity of the hoses or cables during extension or retraction and to solve the problems associated with the retraction purely relying on manpower.
In order to achieve the above objective, this invention provides a hose/cable reeler, comprising: a housing; a reeling wheel assembly, mounted in the housing, and including a reeling wheel axle supported by the housing and a reeling wheel mounted on the reeling wheel axle with the reeling wheel axle serving as a center, the reeling wheel being adapted to wind a hose, cable or the like thereon, and to rotate in a first direction to wind the hose and in a second direction opposite to the first direction to unwind the hose; and a reeling wheel drive mounted in the housing and detachably coupled with the reeling wheel through a clutch to drive the reeling wheel to rotate in the first direction, the reeling wheel being coupled with the reeling wheel drive when the clutch is operated into an engaged state, and the reeling wheel being uncoupled from the reeling wheel drive when the clutch is operated into a disengaged state.
The reeling wheel drive of the invention comprises: a lever, swingably supported by the housing, and having a stationary portion that is pivoted to the housing and a free end that is opposite to the stationary portion, the lever being adapted to swing manually within a predetermined range between a start position and an end position with the stationary portion as a fulcrum, and the lever being connected with a spring and biased by the spring towards the start position; a driven gear mounted coaxially and fixedly with respect to the reeling wheel; a driving gear mounted to engage the driven gear; a transmission gear mounted coaxially with respect to the driving gear; and a transmission member engaged with the transmission gear to drive the transmission gear, the transmission member having mesh teeth on a side facing the transmission gear to mesh with the driving gear, and the transmission member being connected with the lever to reciprocate as the lever swings.
In the above hose/cable reeler, the clutch may be an overrunning clutch, comprising a first clutch half and a second clutch half that are able to axially engage with and disengage from each other and a control mechanism that cooperates with the first clutch half to control the axial engagement and disengagement between the first clutch half and the second clutch half, the control mechanism including: a control member that is able to rotate on the reeling wheel axle and has a first cam portion; a first cam follower portion provided on the first clutch half and cooperated with the first cam portion of the control member; a second cam portion provided on the reeling wheel axle; a second cam follower portion provided on the first clutch half and cooperated with the second cam portion provided on the reeling wheel axle; a compression spring provided between the first clutch half and the second clutch half for biasing the halves in a direction of disengagement thereof, and a rotation damping means to damp down the rotation of the control member, wherein the control member is disposed to be axially stationary relative to the reeling wheel axle, the first clutch half is disposed relative to the reeling wheel axle so as to be movable axially within a determined lengthwise range and be rotatable within a determined angular range, the second clutch half is fixed to the reeling wheel, the first cam portion of the control member and the first cam follower portion of the first clutch half are configured such that when the first clutch half rotates, along with the second clutch half and the reeling wheel, in the second direction relative to the control member or when the reeling wheel rotates in the first direction relative to the reeling wheel axle, the first clutch half moves axially in a direction away from the second clutch half under the bias of the compression spring, whereby the clutch is operated into the disengaged state, and the second cam portion of the reeling wheel axle and the second cam follower portion of the first clutch half are configured such that when the reeling wheel axle rotates in the first direction relative to the first clutch half and the reeling wheel within the determined angular, the first clutch half moves axially towards the second clutch half against the bias of the compression spring, whereby the clutch is operated into the engaged state. The first cam portion may comprise at least one recess having a slope fixedly disposed on the control member and the first cam follower portion comprises at least one cog fixedly disposed on the first clutch half, the cog fitting in the recess and being able to slide along the slope of the recess. The cog may have a slope that is complementary to and mates with the slope of the recess. The second cam portion may comprise at least one key fixedly disposed on a circumferential surface of the reeling wheel axle and the second cam follower portion comprises at least one shaped groove having a slope fixedly disposed on the first clutch half, the key fitting in the shaped groove and being able to slide along the slope of the shaped groove. The key may have a slope that is complementary to and mates with the slope of the shaped groove. Both the first clutch half and the second clutch half may be formed with teeth on opposing end surfaces thereof, the first clutch half and the second clutch half being engaged with each other by means of the teeth. Both the first clutch half and the second clutch half may be formed with a counterbore on opposing end surfaces thereof, the compression spring being disposed between the first clutch half and the second clutch half with its opposite ends seated in the two counterbores respectively. The control member may be formed as a wave wheel with waved teeth on its circumference, the wave wheel being rotatably mounted on the reeling wheel axle, the waved teeth of the wave wheel being engaged with a detent that is mounted to the housing by means of a spring, and the detent engaging the waved teeth of the wave wheel under the bias of the spring, whereby the waved teeth, the detent and the spring constitute the rotation damping means for damping down the rotation of the wave wheel on the reeling wheel axle. The control member may be formed as a belt pulley with a belt winding portion on its circumference, the belt pulley being rotatably mounted on the reeling wheel axle, and a belt being wound on the belt winding portion of the belt pulley with opposite ends of the belt fixed to a stationary portion of the housing under a determined tension, whereby the belt and the belt winding portion constitute the rotation damping means for damping down the rotation of the belt pulley on the reeling wheel axle. The rotation damping means may further comprise a tension spring connected between one end of the belt and the stationary portion of the housing.
In the above hose/cable reeler, the clutch may comprise a first clutch half and a second clutch half that are able to axially engage with and disengage from each other and a control mechanism that cooperates with the first clutch half to control the axial engagement and disengagement between the first clutch half and the second clutch half, both the first clutch half and second clutch half being formed with one-way teeth that are able to engage with each other in a one-way manner, the first clutch half being fixed to the driven gear, and the second clutch half being fixed to the reeling wheel, wherein the control mechanism comprises: an external thread formed on a portion of a circumferential surface of the reeling wheel axle; an internal thread formed in a central bore of the first clutch half and engaging the external thread, the first clutch half being movable axially relative to the reeling wheel axle within a predetermined range by means of a screwing action between the internal thread and the external thread; a compression spring disposed between the first clutch half and second clutch half for biasing the first clutch half and second clutch half in a direction to separate them from each other; and a rotation damping means adapted to damp down the rotation of the reeling wheel axle, wherein the internal thread and the external are configured such that when rotating in the first direction the first clutch half moves axially towards the second clutch half against the bias of the compression spring until it is engaged with the second clutch half. The rotation damping means may comprise a wave wheel that is fixed to the reeling wheel axle and has waved teeth on its circumference, and a detent that is mounted to the housing through a spring and engages the waved teeth of the wave wheel, the detent engaging the waved teeth of the wave wheel under the bias of the spring to damp down the rotation of the wave wheel. The rotation damping means may comprise a belt pulley that is fixed to the reeling wheel axle and has a belt winding portion on its circumference, and a belt that is wound on the belt winding portion of the belt pulley, with opposite ends of the belt being fixed to a stationary portion of the housing under a determined tension, for damping down the rotation of the belt pulley. The rotation damping means may further comprise a tension spring that is connected between one end of the belt and the stationary portion of the housing. Both the first clutch half and the second clutch half may be formed with a counterbore on opposing end surfaces thereof, the compression spring being disposed between the first clutch half and the second clutch half with its opposite ends seated in the two counterbores respectively. The mating internal thread and external thread may be multi start thread.
In the above hose/cable reeler, the reeling wheel axle may comprise a principal reeling wheel axle that is fixed to the housing and a semi reeling wheel axle that is coaxial with the principal reeling wheel axle and is rotatably supported by the housing, and the reeling wheel assembly further comprises a coil spring mounted between the principal reeling wheel axle and the reeling wheel, with one end of the coil spring fixed to the principal reeling wheel axle and other end fixed to the reeling wheel.
In the above hose/cable reeler, the clutch is a manually operated clutch. The manually operated clutch may comprise a first clutch half and a second clutch half that are able to be axially engaged with and disengaged from each other, and a manually operated mechanism that is connected with at least one of the two clutch halves to control the axial engagement and disengagement between the first clutch half and the second clutch half.
In the above hose/cable reeler, a treadle may be mounted on the free end of the lever for treading.
In the above hose/cable reeler, the transmission member in the reeling wheel drive may be a sector gear that is fixed to the lever and swings reciprocally about the stationary portion along with the lever. The sector gear may be an internal gear.
In the above hose/cable reeler, the transmission member in the reeling wheel drive may be a gear rack, one end of which is connected to the lever so as to reciprocate linearly as the lever swings.
Since manpower (e.g., treading of a foot) is used as a moving force to retract a hose or cable, this invention avoids the related problems which may occur when the retraction is achieved completely relying on a retracting coil spring. For example, the brandish, which may occur owing to an excessive retractive force, can be avoided during the retraction of the hose or cable, and a combined drive of manpower and the retractive force of a coil spring is possible. Therefore, the hose/cable reeler of this invention allows for an operation of the hose or cable in a relatively labour-saving, convenient and safe manner.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded view of a treadle hose reeler according to a first embodiment of the invention;
FIG. 2 is an exploded view of a hose distribution mechanism shown in FIG. 1 ;
FIG. 3 is a front view of a first clutch half of an overrunning clutch used in the invention;
FIG. 4 is a sectional view along the A-A line in FIG. 3 ;
FIG. 5 is a sectional view of a second clutch half of the overrunning clutch;
FIG. 6 is a front view of a semi reeling wheel axle;
FIG. 7 is a sectional view along the B-B line in FIG. 6 ;
FIG. 8 is a perspective view of a control member of the overrunning clutch;
FIG. 9 is a sectional view of a principal reeling wheel axle;
FIG. 10 is an assembly diagram of the overrunning clutch;
FIG. 11 is a schematic diagram showing the engagement between the first clutch half and the control member;
FIG. 12 is a schematic diagram showing the movement of various parts of a reeling wheel drive when a treadle is trod down;
FIG. 13 is a schematic diagram showing the movement of the various parts of the reeling wheel drive when the treadle is released;
FIG. 14 is an exploded view of a treadle hose reeler according to a second embodiment of the invention;
FIG. 15 is a front view of a semi reeling wheel axle used in the second embodiment;
FIG. 16 is a sectional view along the B-B line in FIG. 15 ;
FIG. 17 is a perspective view of a transmission member used in the second embodiment;
FIG. 18 is a perspective view of a driven gear used in the second embodiment;
FIG. 19 is a schematic assembly diagram of a driven gear, a semi reeling wheel axle, a compression spring and a transmission member that constitute a clutch in the second embodiment;
FIG. 20 is a schematic diagram showing the movements of various parts of a reeling wheel drive when a treadle is trod down in the second embodiment;
FIG. 21 is a schematic diagram showing the movements of the various parts of the reeling wheel drive when the treadle is released;
FIG. 22 is an exploded view of a reeling wheel drive in a hose reeler according to a third embodiment of the invention;
FIG. 23 is a schematic diagram showing the movements of various parts of the reeling wheel drive when a treadle is trod down in the third embodiment;
FIG. 24 is a schematic diagram showing the movements of the various parts of the reeling wheel drive when the treadle is released in the third embodiment;
FIG. 25 is an exploded view of a treadle hose reeler according to a fourth embodiment of the invention;
FIG. 26 is a schematic diagram showing the movement of various parts of a reeling wheel drive when a treadle is trod down in the fourth embodiment;
FIG. 27 is a schematic diagram showing the movement of the various parts of the reeling wheel drive when the treadle is released in the fourth embodiment;
FIG. 28 is an exploded view of a treadle hose reeler according to a fifth embodiment of the invention;
FIG. 29 is a schematic diagram which shows the movements of various parts of the reeling wheel drive when a treadle is trod down in the fifth embodiment;
FIG. 30 is a schematic diagram showing the movements of the various parts of the reeling wheel drive when the treadle is released in the fifth embodiment;
FIG. 31 shows a modification of main parts (an internal sector gear and a lever) in the reeling wheel drive of the invention shown in FIG. 1 ; and
FIG. 32 shows a modification of the control member in the overrunning clutch of the invention shown in FIG. 8 , wherein (a) is a perspective view and (b) is a schematic assembly diagram of the control member.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Several preferred embodiment of the invention will be described with reference to the accompanying drawings. For the purpose of simplicity and clarity, only the mechanisms and components which are related to the invention will be described in the embodiments in detail, and other mechanisms in the hose reeler such as hose distribution mechanism, water (air) inlet and outlet mechanism and the like which are not related to the invention will be described schematically and briefly.
First Embodiment
See FIGS. 1-13 , which show a hose reeler according to the first embodiment of the invention. The hose reeler is a treadle hose reeler and is use to store up a hose 10 . In order to prevent the hose 10 from being completely wound into the housing, a stopper 9 is fixed at the end of the hose 10 . The hose reeler mainly comprises a housing, a reeling wheel assembly 46 , a clutch 47 , a reeling wheel drive 45 , a hose distribution mechanism and a water (air) inlet and outlet mechanism. The housing is composed of a right housing 3 and a left housing 24 . There is a side cover 36 on the left housing 24 . A partition 37 is provided in the left housing 24 which substantially separates the left housing 24 into two, left and right, chambers. The left chamber is sealed by the side cover 36 and is used to hold a reeling wheel drive 45 . The right chamber is sealed by the right housing 3 and is used to hold a reeling wheel assembly 46 and a clutch 47 .
The reeling wheel assembly 46 comprises a principal reeling wheel axle 15 fixed to the left housing 24 and the right housing 3 , a semi reeling wheel axle 16 rotatably mounted on the principal reeling wheel axle 15 , a coil spring 14 , and a reeling wheel that is mounted on and can rotate about the principal reeling wheel axle 15 . The reeling wheel consists of a left reeling wheel disk 17 and a right reeling wheel disk 13 which are connected together. A central through hole 38 in the left reeling wheel disk 17 is fit with a circumferential surface 48 of the semi reeling wheel axle 16 . A left end of the right reeling wheel disk 13 is fixed to the left reeling wheel disk 17 , and a right end thereof is rotatably supported on a circumferential surface 41 of a stationary axle 4 which is fixed to the right housing 3 . A shaped key 40 on the right end of the principal reeling wheel axle 15 cooperates with a shaped hole 42 in the stationary axle 4 which is fixed to the right housing 3 . In this way, the principal reeling wheel axle 15 is fixed to the right housing 3 through the stationary axle 4 . The left end of the principal reeling wheel axle 15 is movably connected with the semi reeling wheel axle 16 through an axial part 39 provided on the axle 15 and a hole 50 in the axle 16 . On the right end of the principal reeling wheel axle 15 there is a slit 49 . One end of the coil spring 14 is fixed to the right reeling wheel disk 13 and the other end is fixed to the principal reeling wheel axle 15 through the slit 49 .
The clutch 47 is an overrunning clutch which consists of a first clutch half 20 and a second clutch half 18 with teeth on their one end face respectively and a control mechanism which is fit with the first clutch half 20 (the left one in FIG. 1 ). The teeth 51 on the right end face of the first clutch half 20 can be engaged with and disengaged from the teeth 52 on the left end face of the second clutch half 18 , therefore an axial engagement and disengagement between the two clutch halves can be obtained. The control mechanism consists of a control member 21 , a detent 22 , a spring 23 and the semi reeling wheel axle 16 . The second clutch half 18 is fixed to the left reeling wheel disk 17 . On the left side of the second clutch half 18 there is a counterbore 53 . On the right side of the first clutch half 20 there is a counterbore 54 and on the left side of the first clutch half 20 there are one-way cogs 55 . Along the axial direction of the first clutch half 20 there are four shaped grooves 56 each with a shape of .
A compression spring 19 is fit around a circumferential surface of the semi reeling wheel axle 16 , with its one end seated in the counterbore 53 of the second clutch half 18 and the other end seated in the counterbore 54 of the first clutch half 20 . There are four shaped keys 57 having a shape of , which fit with the respective shaped grooves 56 on the first clutch half 20 . The control member 21 is formed as a wave wheel with waved teeth around its circumference. On the right side there are recesses 58 which can be engaged with the one-way cogs 55 on the first clutch half 20 . The control member 21 is rotatably situated around a cylindrical portion of the semi reeling wheel axle 16 , with no axial movement allowed relative to the semi reeling wheel axle 16 . The detent 22 is fixed to a stationary portion of the left housing 24 . One end of the spring 23 is fixed to a stationary portion of the left housing 24 and the other end thereof is connected to the detent 22 . The detent 22 is used to damp down the rotation of the control member 21 in any direction.
The hose distribution mechanism is mounted on the housing and consists of a synchronizing gear 6 , a synchronizing gear cover 5 , a guide column d, a pinion gear a, a two-way trapezoid screw b, a commutator c, a mounting frame e, two small pulleys f, two iron bars g, and a timing toothed belt 7 . The synchronizing gear 6 is coaxially fixed to the right side of the right reeling wheel disk 13 . The synchronizing gear cover 5 is connected to the synchronizing gear 6 which is connected to the hose distribution mechanism through the timing toothed belt 7 . The pinion gear a is situated on one side of the two-way trapezoid screw b to correspond to the synchronizing gear 6 . The mounting frame e is situated on the two-way trapezoid screw b. The commutator c is situated on the mounting frame e. The guide column d is situated on the left housing 24 and the right housing 3 . A round hole 66 in the mounting frame e is fit with the guide column d. The small pulleys are movably connected to the mounting frame e through the two iron bars g. The function of the hose distribution mechanism is to distribute the hose (or cable) in order during winding. When a hose or cable is being wound up, the right reeling wheel disk 13 drives the synchronizing gear 6 to rotate, and the synchronizing gear 6 in turn drives the pinion gear a through the timing toothed belt 7 , therefore the two-way trapezoid screw b is rotated. In this way, the distribution of the hose can be achieved. Once a layer of the hose is full up, the mounting frame will automatically switch over to the next layer by means of the commutator c.
The water (air) inlet and outlet mechanism mainly consists of a water (air) tie-in 2 , a stationary axle 4 and a water (air) inlet connector 11 . One end of the stationary axle 4 is fixed to the principal reeling wheel axle 15 , and the other end 43 thereof is specially shaped and is fit to a shaped hole 44 in the right housing 3 to fix the stationary axle 4 . There is an axial water (air) inlet in the stationary axle 4 with the tie-in 2 fixed to it. The water (air) inlet connector 11 is fit around the stationary axle 4 . On a side of the water (air) inlet connector 11 there is a water (air) outlet. The water (air) outlet of the stationary axle 4 corresponds to the water (air) outlet of the water (air) inlet connector 11 . A water (air) outlet hose 10 wound on the reeling wheel is connected to side water (air) outlet of the water (air) inlet connector 11 . At the joint between the stationary axle 4 and the water (air) inlet connector 11 there is a ring groove in which a sealing ring is fit. On one side of the ring groove of the stationary axle 4 there is a spring washer 12 which allows the stationary axle 4 and the water (air) inlet connector 11 to rotate freely with no leakage of water (air). A water (air) inlet pipe 1 is fixed to the water (air) tie-in 2 .
In this embodiment, the reeling wheel drive 45 consists of a tension spring 31 , a transmission gear 29 , an internal sector gear 30 , a driving gear 27 , a driven gear 28 , secondary axles 25 and 26 , a lever 34 , a treadle 35 and an optional bracket. The bracket consists of two horizontal columns 32 and two vertical cylindrical columns 33 , and is used to limit the movement of the lever 34 . The two columns 32 are fixed to a stationary portion of the left housing 24 . The two ends of the two cylindrical columns 33 are connected to the two columns 32 . The bracket is helpful to define the movement range of lever 34 in a firmer manner. However, in many cases, the bracket is not necessary and can be replaced by equivalent means. The lever 34 is pivotally mounted to the side cover 36 through the secondary axle 26 and can pivot about an axis of the secondary axle 26 . On a free end of the lever 34 there is a treadle 35 which can be trod by a user's foot to apply a force to the lever. An internal sector gear 30 is fixed to a side of the lever 34 opposite to the treadle 35 . The internal sector gear 30 is used as a transmission member which can engage the transmission gear 29 and therefore drive it. The internal sector gear 30 is fixed to the lever 34 in such a way that it can rotate about the secondary axle 26 as the lever 34 swings. The transmission gear 29 is engaged internally with the internal sector gear 30 . The transmission gear 29 and the driving gear 27 are coaxially fixed to the secondary axle 25 which is fixed to a stationary portion of the left housing 24 . The secondary axle 25 can rotate about its axis. The driving gear 27 engages the driven gear 28 externally. The driven gear 28 is coaxially fixed to the semi reeling wheel axle 16 . One end of the tension spring 31 is fixed to a stationary portion of the housing, and the other end thereof is fixed to the lever proximate to the treadle.
When the hose is pulled out, the lever 34 is at the start position with the clutch 47 in the disengaged state. At this time, both the principal reeling wheel axle 15 and the semi reeling wheel axle 16 remain stationary, and the reeling wheel rotates counterclockwise about the principal reeling wheel axle 15 . During the rotation of the reeling wheel, the coil spring 14 is tensioned, and the energy is accumulated.
When the treadle 35 is being pressed down, the lever 34 drives the internal sector gear 30 to rotate counterclockwise. Under the action of the internal sector gear 30 , the transmission gear 29 rotates counterclockwise. Since the driving gear 27 and the transmission gear 29 are fixed coaxially, the driving gear 27 rotates counterclockwise under the driving of the transmission gear 29 . Acted by the driving gear 27 , the driven gear 28 rotates clockwise. Since the driven gear 28 is fixed to the semi reeling wheel axle 16 , the semi reeling wheel axle 16 rotates clockwise under the action of the driven gear 28 . The rotation of the semi reeling wheel axle 16 causes the first clutch half 20 to rotate clockwise. Since at this time the one-way cogs 55 of the first clutch half 20 are engaged with the recesses 58 of the control member 21 and the detent 22 damps down the rotation of the control member 21 , the movement of the first clutch half 20 lags behind the movement of the semi reeling wheel axle 16 . Under the camming actions between the slopes of the shaped keys 57 of the semi reeling wheel axle 16 and the slopes of the shaped grooves 56 of the first clutch half 20 , the one-way cogs 55 of the first clutch half 20 slide out of the recesses 58 of the control member 21 , and the first clutch half moves toward the second clutch half 18 against the action of the compression spring 19 , resulting in the engagement of the teeth 51 of the first clutch half 20 with the teeth 52 of the second clutch half 18 . Therefore, the first clutch half and the second clutch half are engaged with each other axially. Then the first clutch half 20 drives the second clutch half 18 to rotate clockwise, and in turn, drives the reeling wheel to rotate clockwise. Thus, the retraction of the hose is achieved. At this time, the tension spring 31 is in tension.
During the retraction of the hose, energy is released from the coil spring 14 . The coil spring 14 has two functions, one is to increase the retractive force and the other is to keep the continuity of the hose retraction. Of course, the elasticity of the coil spring 14 is lower than that of the coil spring used in a conventional hose reeler in which the hose retraction purely relies on the retracting coil spring. Once the clockwise rotation speed of the reeling wheel is higher than that of the semi reeling wheel axle 16 under the action of the coil spring 14 and the inertia, there will be a relative rotation between the reeling wheel and the semi reeling wheel axle 16 . Meanwhile, the first clutch half 20 rotates clockwise with the reeling wheel. That means there is a relative rotation between the semi reeling wheel axle 16 and first clutch half 20 . When the shaped key 57 of the semi reeling wheel axle 16 slides along the slope of the shaped groove 56 to the opening 59 , i.e., the portion having no slope, of the shaped groove 56 following the rotation of the semi reeling wheel axle 16 , the first clutch half 20 moves axially away from the second clutch half 18 under the action of the compression spring 19 and therefore the clutch is in the disengaged state. In this way, the reeling wheel is allowed to rotate in a speed higher than that of the semi reeling wheel axle 16 .
When the treadle 35 is released, the lever 34 drives the internal sector gear 30 to rotate clockwise under the action of the tension spring 31 , and the transmission gear 29 rotates clockwise under the action of the internal sector gear. Since the driving gear 27 is coaxially fixed to the transmission gear 29 , the driving gear 27 rotates clockwise under the driving of the transmission gear 29 , and the driven gear 28 rotates counterclockwise under the action of the driving gear 27 . Since the driven gear 28 is fixed to the semi reeling wheel axle 16 , under the action of the driven gear 28 , the semi reeling wheel axle 16 rotates counterclockwise. During the counterclockwise rotation of the semi reeling wheel axle 16 , due to the axial bias of the compression spring 19 to the first clutch half 20 and the camming action of the recesses 58 of the control member 21 on the one-way cogs 55 of the first clutch half 20 , the first clutch half 20 moves axially away from the second clutch half 18 until the one-way cogs 56 of the first clutch half 20 entirely fall into the recesses 58 of the control member 21 , and therefore the clutch 47 is in the disengaged state.
Second Embodiment
See FIG. 14-21 which show a hose reeler according to the second embodiment of the invention. In order to be simple, the mechanisms such as the hose distribution mechanism and the water (air) inlet and outlet mechanism which are the same as in the first embodiment will not be described.
In this embodiment, except the clutch 47 B and the semi reeling wheel axle 16 B, the structures are basically the same as in the first embodiment. In this embodiment, the semi reeling wheel axle 16 B is a substantially smooth axle, and its circumferential surface 48 is movably fit to a central through hole 38 of the left disk 17 . The left end of the principal reeling wheel axle 15 is movably coupled to the semi reeling wheel axle 16 B through an axial part 39 provided on the left end of the axle 15 and a hole 50 in the axle 16 . There is a length of external thread 65 proximate the middle portion of the semi reeling wheel axle 16 B.
The reeling wheel drive 45 consists of a tension spring 31 , a transmission gear 29 , an internal sector gear 30 , a driving gear 27 , a driven gear 28 , secondary axles 25 and 26 , a lever 34 , a treadle 35 and an optional bracket. The lever 34 is pivotally mounted to the side cover 36 through the secondary axle 26 and can pivot about an axis of the secondary axle 26 . On a free end of the lever 34 there is a treadle 35 which can be trod by a user's foot to apply a force to the lever. An internal sector gear 30 is fixed to a side of the lever 34 opposite to the treadle 35 . The internal sector gear 30 is used as a transmission member which can engage the transmission gear 29 and therefore drive it. The internal sector gear 30 is fixed to the lever 34 in such a way that it can rotate about the secondary axle 26 as the lever 34 swings. The transmission gear 29 is engaged internally with the internal sector gear 30 . The transmission gear 29 and the driving gear 27 are coaxially fixed to the secondary axle 25 which is fixed to a stationary portion of the left housing 24 . The secondary axle 25 can rotate about its axis. The driving gear 27 engages the driven gear 28 externally. One end of the tension spring 31 is fixed to a stationary portion of the housing, and the other end thereof is fixed to the lever 34 proximate to the treadle.
In this embodiment, the clutch 47 B consists of a driven gear 28 B, a transmission connector 18 B, a semi reeling wheel axle 16 B, and a rotation damping means that damps down the rotation of the semi reeling wheel axle. On a side of the driven gear 28 B facing the reeling wheel there are one-way teeth 63 that are distributed regularly, which corresponds to a first clutch half. There is a counterbore 62 in the driven gear 28 B axially, and in an axial hole of the driven gear there is provided an internal thread 64 . The transmission connector 18 B is coaxially fixed to the reeling wheel. On a side of the transmission connector 18 B facing the driven gear 28 B there are one-way teeth 61 that can mesh with the one-way teeth in a one-way manner, which corresponds to a second clutch half. There is an axial counterbore 60 on the transmission connector 18 B, an axial hole 66 of which is movably fit with a circumferential surface 48 of the semi reeling wheel axle 16 B. The structure of the one-way teeth 61 and 63 which mesh with each other in the one-way manner is well known in art, for example, including the incline teeth arranged circumferentially. The driven gear 28 B and the semi reeling wheel axle 16 B are cooperatively coupled with each other through the internal thread 64 and the external thread 65 , and the driven gear 28 B is allowed to move axially on the semi reeling wheel axle 16 B within a predetermined range via the screwing action of these threads. Preferably, the internal and external threads 64 , 65 are multi start threads. A compression spring 19 B is fit around the circumferential surface of the semi reeling wheel axle 16 B, with one end seated in the counterbore 62 of the driven gear 28 B and the other seated in the counterbore 60 of the transmission connector 18 B. The compression spring 19 B is used to bias the driven gear 28 B in a direction away from the transmission connector 18 B. The rotation damp mechanism consists of a wave wheel 21 B that is fixed to the semi reeling wheel axle 16 B and has waved teeth on its circumference, and a detent 22 that is engaged with the waved teeth of the wave wheel 21 B and is fixed to the left housing 24 through a spring 23 . One end of the spring 23 is fixed to a stationary portion of the left housing 24 and the other end thereof is connected to the detent 22 . The detent 22 is used to damp down the rotation in any direction of the wave wheel 21 B, and in turn, the semi reeling wheel axle 16 B.
When the hose is pulled out, the lever 34 is in the start position and the one-way teeth 63 on the driven gear 28 B and the one-way teeth 61 on the transmission connector 18 B are in the disengaged state. At this time, both the principal reeling wheel axle 15 and the semi reeling wheel axle 16 B remain stationary, and the reeling wheel rotates counterclockwise about the principal reeling wheel axle 15 . During the movement of the reeling wheel, the coil spring 14 is tensioned, which means the energy is accumulated.
When the treadle 35 is being pressed down, the lever 34 drives the internal sector gear 30 to rotate counterclockwise, and the transmission gear 29 rotates counterclockwise under the action of the internal sector gear 30 . Since the driving gear 27 and the transmission gear 29 are fixed coaxially, the driving gear 27 rotates counterclockwise under the driving of the transmission gear 29 . Acted by the driving gear 27 , the driven gear 28 B rotates clockwise. Since the driven gear 28 B is cooperatively coupled with the semi reeling wheel axle 16 B by means of threads, the clockwise rotation of the driven gear 28 B causes the semi reeling wheel axle 16 B to rotate clockwise therewith. However, due to the damping action of the detent 22 on the rotation of the rotation damper 21 B, the rotation of the semi reeling wheel axle 16 B lags behind the rotation of the driven gear 28 B. In this case, the driven gear 28 B moves on the semi reeling wheel axle 16 B toward the transmission connector 18 B via screwing action, until the one-way teeth 63 on the driven gear 28 B mesh with the one-way teeth 61 on the transmission connector 18 B, which operates the clutch 47 B into the engaged state. Then, under the action of the driven gear 28 B, the transmission connector 18 B rotates clockwise, which drives the reeling wheel fixed thereto to rotate clockwise. Therefore the hose is retracted. At this time, the tension spring 31 is in tension.
During the retraction of the hose, energy is released from the coil spring 14 . The coil spring 14 has two functions, one is to increase the retractive force and the other is to keep the continuity of the hose retraction. Of course, the elasticity of the coil spring 14 is lower than that of the coil spring used in a conventional hose reeler in which the hose retraction purely relies on the coil spring. Once the clockwise rotation speed of the reeling wheel is higher than that of the semi reeling wheel axle 16 under the action of the coil spring 14 and the inertia (i.e., there is a relative rotation between the transmission connector 18 B and the driven gear 28 B, and the movement of the driven gear 28 B lags behind the movement of the transmission connector 18 B), due to the damping action of the detent 22 on the wave wheel 21 B, the semi reeling wheel axle 16 B remains stationary relative to the driven gear 28 B, and the one-way teeth 63 of the driven gear 28 B escape from the one-way teeth 61 of the transmission connector 18 B under the actions of the one-way teeth 61 of the transmission connector 18 B and the compression spring 19 B. Then, the transmission gear 28 B moves away from the transmission connector 18 B, until the one-way teeth 63 of the driven gear 28 B is disengaged from the one-way teeth 61 of the transmission connector 18 B. In this way, the reeling wheel is allowed to rotate in a speed higher than that of the semi reeling wheel axle 16 B.
When the treadle 35 is released, under the action of the tension spring 31 , the lever 34 drives the internal sector gear 30 to rotate clockwise, and under the action of the internal sector gear, the transmission gear 29 rotates clockwise. Since the driving gear 27 is coaxially fixed to the transmission gear 29 , driven by the transmission gear 29 , the driving gear 27 rotates clockwise, and the driven gear 28 B rotates counterclockwise under the action of the driving gear 27 . Due to the damping action of the detent 22 on the rotation damper 21 B, the semi reeling wheel axle 16 B remains stationary relative to the driven gear 28 B. In this case, the driven gear 28 B moves away from the transmission connector 18 B via the action of screwing. Then the one-way teeth 63 of the driven gear 28 B are disengaged from the one-way teeth 61 of the transmission connector 18 B. Therefore, the driven gear 28 B is in idle running about the axis of the semi reeling wheel axle 16 B.
Third Embodiment
See FIGS. 22-24 which show a reeling wheel drive of a hose reeler according to the third embodiment of the invention. In the embodiment, except the reeling wheel drive, the components may be substantially the same as those in the first embodiment. Therefore, only the hose reeler drive is described and shown. As for the other parts, reference can be made to the first embodiment.
In this embodiment, the reeling wheel drive 45 B consists of a transmission gear 29 B, a gear rack 30 B, a driving gear 28 C, wire ropes 69 and 70 , pulleys 67 and 68 , a secondary axle 25 B, a tension spring 31 B, a lever 34 , a treadle 35 and an optional bracket. The lever 34 has a stationary portion pivotally mounted to the housing and an opposite free end. On the free end of the lever 34 there is a treadle 35 which can be trod by a user's foot to apply a force to the lever. The stationary portion of the lever 34 is pivotally fixed to the left housing 24 through a pivot 26 B. One end of the wire rope 69 is connected to an approximately middle portion of the lever 34 and the other is connected to the end of the gear rack 30 B proximate to the treadle 35 . One end of the wire rope 70 is connected to the end of the gear rack 30 B away from the treadle 35 and the other end thereof is connected to the tension spring 31 B, with the middle portion tensioned by the pulley 68 , One end of the tension spring 31 B is connected to the wire rope 70 and the other to a stationary portion of the left housing 24 . The pulleys 67 , 68 are fixed to a stationary portion of the left housing 24 respectively. The gear rack 29 B is disposed such that when the treadle 35 is in the start position and end position the transmission gear 29 B always meshes with the gear rack 30 B. The transmission gear 29 B and the driving gear 27 B are coaxially fixed to the secondary axle 25 B which is fixed to a stationary portion of the left housing 24 . The secondary axle 25 B is rotatable about its axis. The driving gear 27 B is externally meshed with the driven gear 28 C. The driven gear 28 C and the semi reeling wheel axle 16 are coaxially fixed with each other.
When the hose is pulled out, the lever 34 is in the start position and the clutch 47 is in the disengaged state. At this time, both the principal reeling wheel axle 15 and the semi reeling wheel axle 16 remain stationary, and the reeling wheel rotates counterclockwise about the principal reeling wheel axle 15 . During the rotation of the reeling wheel, the coil spring 14 is tensioned, which means energy is accumulated.
When the treadle 35 is being pressed down, the lever 34 drives the wire rope 69 to move in a direction in which the hose is retracted, and therefore the gear rack 30 B is driven to move in the direction in which the hose is retracted. Under the action of the gear rack 30 B, the transmission gear 29 B rotates counterclockwise. Since the transmission gear 29 B is coaxially fixed to the driving gear 27 B, the transmission gear 29 B drives the driving gear 27 B to rotate counterclockwise, and under the action of the driving gear 27 B, the driven gear 28 C rotates clockwise. As the driven gear 28 C is fixed to the semi reeling wheel axle 16 , under the action of the driven gear 28 C, the semi reeling wheel axle 16 rotates clockwise. At this time, the clutch is in the engaged state (the principle is the same as in the first embodiment), and the reeling wheel rotates clockwise, whereby the hose is retracted. At this time, the tension spring 31 B is in tension.
During the retraction of the hose, energy is released from the coil spring 14 . Once the clockwise rotation speed of the reeling wheel is higher than that of the semi reeling wheel axle 16 under the action of the coil spring 14 and the inertia, there will be a relative rotation between the reeling wheel and the semi reeling wheel axle. Since the first clutch half 20 rotates clockwise following the reeling wheel, that means there is a relative rotation between the semi reeling wheel axle 16 and the first clutch half 20 . When the shaped key 57 on the semi reeling wheel axle 16 slides along the slope of the shaped groove 56 to the opening 59 of the shaped groove 56 as the semi reeling wheel axle 16 rotates, the first clutch half 20 moves axially away from the second clutch half 18 under the action of the compression spring 19 , and therefore the clutch is in the disengaged state. In this way, the reeling wheel is allowed to rotate in a speed higher than that of the semi reeling wheel axle 16 .
When the treadle 35 is released, under the action of the tension spring 31 B, the wire rope 70 moves in the direction in which the hose is pulled out, and therefore, the gear rack 30 B is driven. And under the action of the gear rack 30 B, the transmission gear 29 B rotates clockwise. Since the driving gear 27 B is coaxially fixed to the transmission gear 29 B, the driving gear 27 B rotates clockwise under the driving of the transmission gear 29 B, and the driven gear 28 C rotates counterclockwise under the driving of the driving gear 27 B. Since the driven gear 28 C is fixed to the semi reeling wheel axle 16 , under the action of the driven gear 28 C, the semi reeling wheel axle 16 rotates counterclockwise. During the counterclockwise rotation of the semi reeling wheel axle 16 , due to the axial bias of the compression spring 19 to the first clutch half 20 and the camming actions of the recesses 58 of the control member 21 on the one-way cogs 55 of the first clutch half 20 , the first clutch half 20 moves axially away from the second clutch half 18 until the one-way cogs 55 of the first clutch half 20 entirely falls into the recesses 58 of the control member 21 , whereby the clutch 47 is in the disengaged state.
Fourth Embodiment
See FIGS. 25-27 which show a hose reeler according to the forth embodiment of the invention. This embodiment is substantially the same as the first embodiment of the invention with the difference lying in that a coil spring as in the first embodiment is not used and a single axle is employed here as a reeling wheel axle to replace the combination of the principal reeling wheel axle and the semi reeling wheel axle in the first embodiment. Therefore, only the portion different from the first embodiment will be described, and the remainders can refer to the first embodiment.
In this embodiment, since no coil spring is used in the reeling wheel assembly 46 C, the reeling wheel axle 15 B can be a single axle. An axial hole 42 B is provided at one end of a stationary axle 4 proximate to the reeling wheel axle 15 B, and movably fits with a circumferential surface 40 B of the reeling wheel axle 15 B. A circumferential surface 48 B of the reeling wheel axle 15 B is fit to a central through hole 38 of the left disk 17 . There are four shaped keys 57 in a shape of on the circumferential surface 48 B of the reeling wheel axle 15 B that can fit with the shaped grooves 56 of the first clutch half 20 .
When the hose is pulled out, the lever 34 is in the start position and the clutch 47 is in the disengaged state. At this time the reeling wheel axle 15 B remains stationary and the reeling wheel rotates counterclockwise about the reeling wheel axle 15 B.
When the treadle 35 is being pressed down, the lever 34 drives the internal sector gear 30 to rotate counterclockwise. Under the action of the internal sector gear 30 , the transmission gear 29 rotates counterclockwise. Since the driving gear 27 and the transmission gear 29 are fixed coaxially, the driving gear 27 rotates counterclockwise under the driving of the transmission gear 29 . Acted by the driving gear 27 , the driven gear 28 rotates clockwise. Since the driven gear 28 is fixed to the reeling wheel axle 15 B, the reeling wheel axle 15 B rotates clockwise under the action of the driven gear 28 . The rotation of the reeling wheel axle 15 B causes the first clutch half 20 to rotate clockwise. Since at this time the one-way cogs 55 of the first clutch half 20 are engaged with the recesses 58 of the control member 21 and the detent 22 damps down the rotation of the control member 21 , the movement of the first clutch half 20 lags behind the movement of the semi reeling wheel axle 16 . Under the camming actions between the slopes of the shaped keys 57 of the reeling wheel axle 15 B and the slopes of the shaped grooves 56 of the first clutch half 20 , the one-way cogs 55 of the first clutch half 20 slide out of the recesses 58 of the control member 21 , and the first clutch half moves toward the second clutch half 18 , resulting in the engagement of the teeth 51 of the first clutch half 20 with the teeth 52 of the second clutch half 18 . Therefore, the first clutch half and the second clutch half are engaged with each other axially. Then the first clutch half 20 drives the second clutch half 18 to rotate clockwise, and in turn, drives the reeling wheel to rotate clockwise. Thus, the retraction of the hose is achieved. At this time, the tension spring 31 is in tension.
Once the clockwise rotation speed of the reeling wheel is higher than that of the reeling wheel axle 15 B due to the action of the inertia during the retraction of the hose, there will be a relative rotation between the reeling wheel and the reeling wheel axle 15 B. Since the first clutch half 20 rotates clockwise as the reeling wheel rotates, that means there is a relative rotation between the reeling wheel axle 15 B and first clutch half 20 . When the shaped key 57 of the reeling wheel axle 15 B slides along the slope of the shaped groove 56 to the opening 59 of the shaped groove 60 (i.e., a portion without slope) as the reeling wheel axle 15 B rotates, the first clutch half 20 moves axially away from the second clutch half 18 under the action of the compression spring 19 , and therefore the clutch is in the disengaged state. In this way, the reeling wheel is allowed to rotate in a speed higher than that of the reeling wheel axle 15 B.
When the treadle 35 is released, the lever 34 drives the internal sector gear 30 to rotate clockwise under the action of the tension spring 31 , and the transmission gear 29 rotates clockwise under the action of the internal sector gear. Since the driving gear 27 is coaxially fixed to the transmission gear 29 , the driving gear 27 rotates clockwise under the driving of the transmission gear 29 , and the driven gear 28 rotates counterclockwise under the action of the driving gear 27 . Since the driven gear 28 is fixed to the reeling wheel axle 15 B, under the action of the driven gear 28 , the reeling wheel axle 15 B rotates counterclockwise. During the counterclockwise rotation of the reeling wheel axle 15 B, due to the axial bias of the compression spring 19 to the first clutch half 20 and the camming action of the recesses 58 of the control member 21 on the one-way cogs 55 of the first clutch half 20 , the first clutch half 20 moves axially away from the second clutch half 18 until the one-way cogs 56 of the first clutch half 20 entirely fall into the recesses 58 of the control member 21 , and therefore the clutch 47 is in the disengaged state.
Fifth Embodiment
See FIGS. 28-30 which show a hose reeler according to the fifth embodiment of the invention. This embodiment is substantially the same as the second embodiment of the invention with the difference only lying in that the coil spring in the second embodiment is not used and a single axle is employed here as a reeling wheel axle to replace the combination of the principal reeling wheel axle and the semi reeling wheel axle in the second embodiment. Therefore, only the portion different from the first embodiment will be described, and the remainder can refer to the second embodiment.
In this embodiment, since no coil spring is used in the reeling wheel assembly 46 C, the reeling wheel axle 15 C can be a single axle. There is an axial hole 42 B at one end of a stationary axle 4 proximate to the reeling wheel axle 15 C. The axial hole 42 B can movably fit with a circumferential surface 40 C of the reeling wheel axle 15 C which in turn is fit to a central through hole 38 in the left disk 17 of the reeling wheel. There is a length of external thread 65 on a side of reeling wheel axle 15 C proximate to the left disk 17 .
When the hose is pulled out, the lever 34 is in the start position and the one-way teeth 63 on the driven gear 28 B and the one-way teeth 61 on the transmission connector 18 B are disengaged, and the clutch 47 B is in the disengaged state. At this time, the reeling wheel axle 15 C remains stationary, and the reeling wheel rotates counterclockwise about the reeling wheel axle 15 C.
When the treadle 35 is being pressed down, the lever 34 drives the internal sector gear 30 to rotate counterclockwise, and the transmission gear 29 rotates counterclockwise under the driving of the internal sector gear 30 . Since the driving gear 27 and the transmission gear 29 are fixed coaxially, the driving gear 27 rotates counterclockwise under the driving of the transmission gear 29 . Acted by the driving gear 27 , the driven gear 28 B rotates clockwise. Since the driven gear 28 B is fit with the reeling wheel axle 15 C by means of threads, the clockwise rotation of the driven gear 28 B causes the reeling wheel axle 15 C to rotate clockwise therewith. However, due to the damping action of the detent 22 on the wave wheel 21 B, the rotation of the reeling wheel axle 15 C lags behind the rotation of the driven gear 28 B. In this case, the driven gear 28 B moves toward the transmission connector 18 B via screwing action, until the one-way teeth 63 on the driven gear 28 B mesh with the one-way teeth 61 on the transmission connector 18 B, and the transmission connector 18 B rotates clockwise under the action of driven gear 28 B thereby to drive the reeling wheel, which is fixed to the transmission connector, to rotate clockwise. Therefore the hose is retracted. At this time, the tension spring 31 is in tension.
During the retraction of the hose, once the clockwise rotation speed of the reeling wheel is higher than that of the reeling wheel axle 15 C due to the action of inertia (i.e., there is a relative rotation between the transmission connector 18 B and the driven gear 28 B, and the movement of the driven gear 28 B lags behind that of the transmission connector 18 B), the reeling wheel axle 15 C remains stationary relative to the driven gear 28 B due to the damping action of the detent 22 on the wave wheel 21 B. The one-way teeth 63 of the driven gear 28 B escape from the one-way teeth 61 of the transmission connector 18 B under the action of the one-way teeth 61 of the transmission connector 18 B and the compression spring 19 B, and the transmission gear 28 B moves away from the transmission connector 18 B until the one-way teeth 63 of the driven gear 28 B is disengaged from the one-way teeth 61 of the transmission connector 18 B. In this way, the reeling wheel is allowed to rotate in a speed higher than that of the reeling wheel axle 15 C.
When the treadle 35 is released, the lever 34 drives the internal sector gear 30 to rotate clockwise under the action of the tension spring 31 , and the transmission gear 29 rotates clockwise under the action of the internal sector gear 30 . Since the driving gear 27 is coaxially fixed to the transmission gear 29 , the driving gear 27 rotates clockwise under the driving of the transmission gear 29 , and the driven gear 28 B rotates counterclockwise under the action of the driving gear 27 . Due to the damping action of the detent 22 on the wave wheel 21 B, the reeling wheel axle 15 C remains stationary relative to the driven gear 28 B. Then the one-way teeth 63 of the driven gear 28 B escape from the one-way teeth 61 of transmission connector 18 B and the driven gear 28 B move away from transmission connector 18 B. Therefore, the driven gear 28 B is in idle running about the axis of the reeling wheel axle 15 C.
FIG. 31 shows an optional modification of the internal sector gear and the lever of the reeling wheel drive shown in FIG. 1 in accordance with the present invention. In this modification, the internal sector gear 30 ′ and the lever 34 ′ are at the same side of the pivot P (corresponding to the axis of the secondary axle 26 in FIG. 1 ). Swinging about the pivot P, the lever 34 ′ drives the internal sector gear 30 ′ to swing, and therefore the transmission gear 29 which internally meshes with the internal sector gear 30 ′ is driven. This modification is helpful in reducing the size of the lever-internal sector gear assembly.
FIG. 32 shows a modification of the control mechanism of the overrunning clutch shown in FIG. 1 and FIG. 8 in accordance with the present invention. FIG. 32( a ) is a perspective view of a control member of the mechanism and FIG. 32( b ) is a schematic diagram which shows the assembly of the control member. In the modification, the control member is a belt pulley 21 ′ having a belt winding portion 211 ′ on its circumference and a belt 22 ′ winding around the belt winding portion 211 ′. Opposite ends of the belt 22 ′ are fixed to a stationary portion (for example, the left housing 24 ) with one end tensioned by a spring 23 ′ at a predetermined tension force. That is to say, the control member 21 , the detent 22 and the spring 23 constituting the control mechanism of the first embodiment of the invention are replaced by a control member in the form of a belt pulley 21 ′, a belt 22 ′ and a spring 23 ′, with the semi reeling wheel axle 16 unchanged. Except the belt winding portion 211 ′, the structures of the control member 21 ′ are substantially the same as the control member 21 in the first embodiment. When the belt pulley 21 ′ rotates in one direction (the counterclockwise direction in FIG. 32( b )), the spring 23 ′ is tensioned, and therefore the damping force applied by belt 22 ′ to the belt pulley 21 ′ is increased and the rotation of the belt pulley is damped down. This shows that the function of the above pulley-belt arrangement is substantially the same as that of the wave wheel-detent arrangement in the first embodiment of the invention, i.e., both to damp down the rotation of the control member.
A detailed description has been given to the various embodiments of the invention in the above. It is understood that the invention is not limited to these exemplary embodiments. Those skilled in the art can make varieties of equivalent modifications and changes to the above embodiments within the present inventive concept. For example, although in the embodiments described herein the lever in the reeling wheel drive is a foot-treading type, a hand pulling or other appropriate types can be adopted. Although in the described embodiments an automatic overrunning clutch is used, a manually operated or other appropriate clutches can be used, e.g., a manually operated clutch (such a manual-type clutch is well known) comprising first and second clutch halves that can be engaged with or disengaged from each other axially and a manually operated mechanism that is connected with one of the first and second clutch halves and extends out of a housing of a hose/cable reeler for manipulation by an operator to control the engagement and disengagement between the halves. Although in the described embodiments the transmission member in the reeling wheel drive is a gear rack or an internal sector gear, an external gear or other appropriate forms can be employed. Although in the described embodiments the rotation damping mechanism comprises a wave wheel-detent or a pulley-belt arrangement, any other known appropriate structures which can damp down the rotation can be used. Therefore, the scope of the invention should not limited to the described embodiments and is intended to be defined by the appended claims. | This invention discloses a hose or cable reeler that can retract a hose or cable without the need for a retracting coil spring. The reeler generally comprises a reeling wheel assembly and a reeling wheel drive. The reeling wheel assembly is detachably coupled with the reeling wheel drive by means of a clutch. The reeling wheel drive mainly comprises a gear transmission chain, and is operated through a lever by manpower (e.g., treading of a foot). Since manpower is used to retract the hose or cable, this invention avoids the related problems that may occur when the retraction is achieved completely relying on the coil spring. For example, the disordered brandish, which may occur owing to an excessive retractive force, can be avoided during the retraction of the hose or cable, and a combined drive of manpower and retractive force of the coil spring is possible. Therefore, the hose (cable) reeler of this disclosure allows for an operation of the hose or cable in a relatively laborsaving, convenient and safe manner. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to use of a specific class of diaminoalcohols in admixture with an amino acid as cosolvent therefor in an aqueous absorbing solution for "hot pot" type acid gas scrubbing processes.
2. Description of Related Patents
Recently, it was shown in U.S. Pat. No. 4,112,050 that sterically hindered amines are superior to diethanolamine (DEA) as promoters for alkaline salts in the "hot pot" acid gas scrubbing process. U.S. Pat. No. 4,094,957 describes an improvement to this process whereby amino acids, particularly sterically hindered amino acids, serve to prevent phase separation of the aqueous solution containing sterically hindered amines at high temperatures and low fractional conversions during the acid gas scrubbing process.
While combinations of sterically hindered diamines such as N-cyclohexyl propanediamine (CHPD) with a cosolvent such as pipecolinic acid represent preferred activator systems in U.S. Pat. No. 4,094,957 for promoting hot carbonate CO 2 scrubbing operations, there are certain disadvantages associated therewith. One difficulty is that sterically hindered primary-secondary diamines such as CHPD are unstable in the presence of CO 2 and tend to enter into undesirable intramolecular condensation reactions therewith to form a cyclic urea precipitate, which reactions are catalyzed by any H 2 S present in the gaseous system. The side reaction of CHPD with CO 2 can be represented as follows: ##STR1## Not only is the diamine consumed by this reaction, but the insoluble cyclic urea must be removed from the system to avoid congestion of the plant operation. Another drawback is that many sterically hindered diamines are highly volatile, resulting in substantial loss thereof during the scrubbing process. This volatility problem is not unique to unstable diamines but is also encountered with many other diamines which are stable in the presence of CO 2 and are effective in enhancing the rate of CO 2 scrubbing.
SUMMARY OF THE INVENTION
It has now been discovered that a certain family of non-sterically hindered diaminoalcohol compounds containing at least one hydroxyl group and a tertiary amino group separated by four methylene groups from a primary amino group are stable in the presence of a CO 2 and H 2 S gaseous mixture, are nonvolatile, and, together with an amino acid cosolvent, form a soluble amino activator system which perform effectively in hot carbonate scrubbing operations. This discovery is unexpected since closely analogous diaminoalcohols having three methylene groups between the amino groups were found to be unstable in the presence of CO 2 and H 2 S.
In one embodiment of the present invention there is provided a process for the removal of CO 2 from a gaseous stream containing CO 2 which comprises (1) in an absorption step, absorbing CO 2 from said gaseous stream with an aqueous absorbing solution comprising (a) a basic alkali metal salt or hydroxide selected from the group consisting of alkali metal bicarbonates, carbonates, hydroxides, borates, phosphates and their mixtures, and (b) an activator or promoter system for said basic alkali metal salt or hydroxide comprising (i) at least one diaminoalcohol of the following general formula:
H.sub.2 N--(CH.sub.2).sub.4 --NRR'
wherein R and R' each independently represent a C 1 -C 6 alkyl group and either R or R' or both R and R' have a terminal or pendant hydroxyl group, and (ii) an amino acid which has the capability to increase the solubility of said diaminoalcohols in alkaline aqueous conditions at elevated temperatures, and (2) in a desorption and regeneration step, desorbing at least a portion of the absorbed CO 2 from said absorbing solution.
As another embodiment of the invention there is provided an aqueous acid gas scrubbing composition comprising: (a) 10 to about 40% by weight of an alkali metal salt or hydroxide, (b) 2 to about 20% by weight of a diaminoalcohol of the formula given above, (c) 2 to about 20% by weight of an amino acid which has the capability to increase the solubility of the diaminoalcohols in alkaline aqueous conditions at elevated temperatures, and (d) the balance, water.
The mole ratio of diaminoalcohol to amino acid may vary widely but is preferably 1:3 to 3:1, most preferably 1:1. The amino acid may be added to the scrubbing solution containing the diaminoalcohol all at once or in increments during the gas scrubbing operation.
The non-sterically hindered diaminoalcohol compound herein may be any compound which is water soluble in the presence of the amino acid co-promoter and has at least one hydroxyl group and a tertiary amino group separated by four methylene groups from a primary amino group, as represented by the formula given above. Typical such diaminoalcohols include N-(2-hydroxyethyl)-N-(n-propyl)-1,4-butanediamine, N-(2-hydroxyethyl)-N-(isopentyl)-1,4-butanediamine, N,N-di(2-hydroxyethyl)-1,4-butanediamine, N-(2-hydroxypropyl)-N-methyl-1,4-butanediamine, and the like. The preferred diaminoalcohols herein are those containing only one hydroxyl group, and most preferred is N-(2-hydroxyethyl)-N-(n-propyl)-1,4-butanediamine.
The amino acids herein include any amino acids which are soluble in the alkaline aqueous solution to be used in the acid gas treating solution. Preferably, the amino acid will have 4 to 8 carbon atoms and one amino moiety and will be free of any hydroxyl group. Especially preferred within this category are tertiary amino acids, defined as amino acids wherein the amino moiety is a tertiary amino moiety such as N,N-dimethyl glycine and N,N-diethyl glycine. Also especially preferred are sterically hindered amino acids of 4 to 8 carbon atoms defined as those containing at least one secondary amino moiety attached to either a secondary or tertiary carbon atom or a primary amino moiety attached to a tertiary carbon atom. At least one of the nitrogen atoms will have a sterically hindered structure. Typical sterically hindered amino acids useful in the practice of the present invention will include N-secondary butyl glycine, pipecolinic acid, N-isopropyl glycine, N-2-amyl glycine, N-isopropyl alanine, N-secondary butyl alanine, 2-amino-2-methyl butyric acid, and 2-amino-2-methyl valeric acid.
In general, the aqueous scrubbing solution will comprise an alkaline material comprising a basic alkali metal salt or alkali metal hydroxide selected from Group IA of the Periodic Table of Elements. More preferably, the alkali metal salt or hydroxide in the scrubbing solution is potassium or sodium borate, carbonate, hydroxide, phosphate, or bicarbonate, or mixtures thereof. Most preferably, the alkaline material is potassium carbonate.
The alkaline material comprising the basic alkali metal or salt or alkali metal hydroxide may be present in the scrubbing solution in the range from about 10% to about 40% by weight, preferably from 20% to about 35% by weight. The actual amount of alkaline material chosen will be such that the alkaline material and the amino acid activator or promoter system remain in solution throughout the entire cycle of absorption of CO 2 from the gas stream and desorption of CO 2 from the solution in the regeneration step. Likewise, the amount and mole ratio of the amino acid to the diaminoalcohol is maintained such that they remain in solution as a single phase throughout the absorption and regeneration steps. Typically, these criteria are met by including from about 2 to about 20% by weight of the amino acid, preferably from 5 to 15% by weight, more preferably, 5 to 10% by weight of the amino acid and from 2 to about 20% by weight, preferably, 5 to about 15% by weight of the diaminoalcohol.
The aqueous scrubbing solution may include a variety of additives typically used in acid gas scrubbing processes, e.g., antifoaming agents, antioxidants, corrosion inhibitors and the like. The amount of these additives will typically be in the range that they are effective, i.e., an effective amount.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The term acid gas includes CO 2 alone or in combination with H 2 S, CS 2 , HCN, COS and the oxides and sulfur derivatives of C 1 to C 4 hydrocarbons. These acid gases may be present in trace amounts within a gaseous mixture or in major proportions.
The contacting of the absorbent mixture and the acid gas may take place in any suitable contacting tower. In such processes, the gaseous mixture from which the acid gases are to be removed may be brought into intimate contact with the absorbing solution using conventional means, such as a tower packed with, for example, ceramic rings or with bubble cap plates or sieve plates, or a bubble reactor.
In a preferred mode of practicing the invention, the absorption step is conducted by feeding the gaseous mixture into the base of the tower while fresh absorbing solution is fed into the top. The gaseous mixture freed largely from acid gases emerges from the top. Preferably, the temperature of the absorbing solution during the absorption step is in the range from about 25° to about 200° C., and more preferably from 35° to about 150° C. Pressures may vary widely; acceptable pressures are between 5 and 2000 psia, preferably 100 to 1500 psia, and most preferably 200 to 1000 psia in the absorber. In the desorber, the pressures will range from about 5 to 100 psig. The partial pressure of the acid gas, e.g., CO 2 in the feed mixture will preferably be in the range from about 0.1 to about 500 psia, and more preferably in the range from about 1 to about 400 psia. The contacting takes place under conditions such that the acid gas, e.g., CO 2 , is absorbed by the solution. Generally, the countercurrent contacting to remove the acid gas will last for a period of from 0.1 to 60 minutes, preferably 1 to 5 minutes. During absorption, the solution is maintained in a single phase. The amino acid aids in reducing foam in the contacting vessels.
The aqueous absorption solution comprising the alkaline material and the activator system of diaminoalcohol and amino acid which is saturated or partially saturated with gases, such as CO 2 and H 2 S, may be regenerated so that it may be recycled back to the absorber. The regeneration should also take place in a single liquid phase. Therefore, the presence of a highly water-soluble amino acid as cosolvent provides an advantage in this part of the overall acid gas scrubbing process. The regeneration or desorption in accomplished by conventional means, such as pressure reduction, which causes the acid gases to flash off by passing the solution into a tower of similar construction to that used in the absorption step, at or near the top of the tower, and passing an inert gas such as air or nitrogen or preferably steam up the tower. The temperature of the solution during the regeneration step may be the same as used in the absorption step, i.e., 25° to about 200° C., and preferably 35° to about 150° C. The absorbing solution, after being cleansed of at least a portion of the acid bodies, may be recycled back to the absorbing tower. Makeup absorbent may be added as needed. Single phase is maintained during desorption by controlling the acid gas, e.g., CO 2 , level so that it does not fall into the region where two liquid phases form. This, of course, following the practice of the present invention, is facilitated by the use of a highly water soluble amino acid in the mixture.
As a typical example, during desorption, the acid gas (e.g., CO 2 ) - rich solution from the high pressure absorber is sent first to a flash chamber where steam and some CO 2 are flashed from solution at low pressure. The amount of CO 2 flashed off will, in general, be about 35 to 40% of the net CO 2 recovered in the flash and stripper. This is increased somewhat, e.g., to 40 to 50%, with the high desorption rate promoter system owing to a closer approach to equilibrium in the flash. Solution from the flash drum is then steam stripped in the packed or plate tower, stripping steam having been generated in the reboiler in the base of the stripper. Pressure in the flash drum and stripper is usually 16 to about 100 psia, preferably 16 to about 30 psia, and the temperature is in the range from about 25° to about 200° C., preferably 35° to about 150° C., and more preferably 100° to about 140° C. Stripper and flash temperatures will, of course, depend on stripper pressure, thus at about 16 to 25 psia stripper pressures, the temperature will preferably be about 100° to about 140° C. during desorption. Single phase is maintained during desorption by regulating the amount of acid gas, e.g., CO 2 , recovered.
In the most preferred embodiment of the present invention, the acid gas, e.g., CO 2 is removed from a gaseous stream by means of a process which comprises, in sequential steps, (1) contacting the gaseous stream with a solution comprising 10 to about 40 weight percent, preferably 20 to about 30 weight percent of potassium carbonate, an activator or promoter system comprising 2 to about 20 weight percent, preferably 5 to about 15 weight percent, of the diaminoalcohol as herein defined, and 2 to about 20 weight percent, preferably 5 to about 15 weight percent, more preferably 5 to about 10 weight percent, of the amino acid as herein defined, the balance of said solution being comprised of water, said contacting being conducted at conditions whereby the acid gas is absorbed in said solution, and preferably at a temperature ranging from 25° to about 200° C., more preferably from 35° to about 150° C. and a pressure ranging from 100 to about 1500 psia, and (2) regenerating said solution at conditions whereby said acid gas is desorbed from said solution. By practicing the present invention, one can operate the process above described at conditions whereby the working capacity, which is the difference in moles of acid gas absorbed in the solution at the termination of steps (1) and (2) based on the moles of potassium carbonate originally present, is comparable to that obtained under the same operating conditions for removing acid gases from gaseous streams, wherein sterically hindered diamines or diaminoalcohols with fewer methylene groups between the amino groups are employed with an amino acid cosolvent. In other words, working capacity is defined as follows: ##EQU1##
It should be noted that throughout the specification wherein working capacity is referred to, the term may be defined as the difference between CO 2 loading in solution at absorption conditions (step 1) and the CO 2 loading in solution at regeneration conditions (step 2) each divided by the initial moles of potassium carbonate. The working capacity is equivalent to the thermodynamic cyclic capacity, that is, the loading is measured at equilibrium conditions. This working capacity may be obtained from the vapor-liquid equilibrium isotherm, that is, from the relation between the CO 2 pressure in the gas and the acid gas, e.g., CO 2 loading in the solution at equilibrium at a given temperature. To calculate thermodynamic cyclic capacity, the following parameters must usually be specified: (1) acid gas, e.g., CO 2 , absorption pressure, (2) acid gas, e.g., CO 2 , regeneration pressure, (3) temperature of absorption, (4) temperature of regeneration, (5) solution composition, that is, weight percent amino acid, weight percent diaminoalcohol and weight percent of the alkaline salt or hydroxide, for example potassium carbonate, and (6 ) gas composition.
Besides providing working capacity and rates of absorption and desorption which are comparable to that of the sterically hindered diamines and other diaminoalcohols useful for this purpose, the specific class of diaminoalcohols herein have lower volatility than many sterically hindered diamines and have increased stability in the presence of CO 2 gas.
Steam requirements are the major part of the energy cost of operating an acid gas, e.g., CO 2 scrubbing unit. Substantial reduction in energy, i.e., operating costs will be obtained by the use of the process wherein the mixture is utilized. Additional savings from new plant investment reduction and debottlenecking of existing plants may also be obtained by the use of the mixture of the invention. The removal of acid gases such as CO 2 from gas mixtures is of major industrial importance, particularly the systems which utilize potassium carbonate activated by the unique activator or promoter system of the present invention.
While the sterically hindered amines, as shown in U.S. Pat. No. 4,112,050, provide unique benefits in their ability to improve the working capacity in the acid scrubbing process, their efficiency may decrease in alkaline "hot pot" (hot potassium carbonate) scrubbing systems at high temperatures and at low concentrations of the acid gas due to phase separation. Therefore, full advantage of the highly effective sterically hindered amines cannot always be utilized at these operating conditions. The addition of an amino acid, as a cosolvent, as shown in U.S. Pat. No. 4,094,957, solves the problem of phase separation and enables a more complete utilization of sterically hindered amines as the alkaline materials activator or promoter. This result was unexpected for the reason that many sterically hindered amino acids (including the sterically hindered amino acid, pipecolinic acid) alone, while soluble in these alkaline systems, are not as effective as activators in acid gas scrubbing processes as the other sterically hindered amino compounds. The specific admixture, as instantly claimed and disclosed, while not employing a sterically hindered diamino compound, provides the same working capacity and/or rates of CO 2 absorption as those previously reported in U.S. Pat. No. 4,094,957, particularly the N-cyclohexyl 1,3-propanediamine and pipecolinic acid promoter system.
The absorbing solution of the present invention, as described above, will be comprised of a major proportion of the alkaline materials, e.g., alkali metal salts of hydroxides and a minor proportion of the amine activator system. The remainder of the solution will be comprised of water and/or other commonly used additives, such as anti-foaming agents, antioxidants, corrosion inhibitors, etc. Examples of such additives include arsenious anhydride, selenious and tellurous acid, protides, vanadium oxides, e.g., V 2 O 3 , chromates, e.g., K 2 Cr 2 O 7 , etc.
Representative non-sterically hindered diaminoalcohol compounds for use in the present invention include: N-(2-hydroxyethyl)-N-(n-propyl)-1,4-butanediamine, N-(2-hydroxyethyl)-N-(isopentyl)-1,4-butanediamine, N,N-di(2-hydroxyethyl)-1,4-butanediamine, N-(2-hydroxypropyl)-N-methyl-1,4-butanediamine, and the like.
Many of the amino acids useful in the practice of the present invention are either available commercially or may be prepared by various known procedures. Representative amino acids applicable herein include: N,N-diethyl glycine, N,N-dimethyl glycine, pipecolinic acid, N-secondary butyl glycine, N-2-amyl glycine, N-isopropyl glycine, N-secondary butyl-alpha-alanine, 2-amino-2-methyl butyric acid, and 2-amino-2-methyl valeric acid. Particularly preferred for use herein are pipecolinic acid and N-secondary butyl glycine.
The invention is illustrated further by the following examples which, however, are not to be taken as limiting in any respect. All parts and percentages, unless expressly stated to be otherwise, are by weight.
EXAMPLE 1
The reaction apparatus consists of an absorber and a desorber as shown in FIG. 1 of U.S. Pat. No. 4,112,050 incorporated herein by reference. The absorber is a vessel having a capacity of 2.5 liters and a diameter of 10 cm, equipped with a heating jacket and a stirrer. A pump removes liquid from the bottom of the reactor and feeds it back to above the liquid level through a stainless-steel sparger. Nitrogen and CO 2 can be fed to the bottom of the cell through a sparger.
The desorber is a 1-liter reactor, equipped with teflon blade stirrer, gas sparger, reflux condenser and thermometer.
The following reagents were put into a 2-liter Erlenmeyer flask:
0.35 mole of the amine indicated in Table 1
0.17 mole of pipecolinic acid
225 g of K 2 CO 3
water to make 750 g total solution
When all solids had dissolved, the mixture was put into the absorber and brought to 80° C. The apparatus was closed and evacuated until the liquid began to boil. At this point CO 2 gas was admitted. At the end of the absorption the rich solution was transferred to the desorber and boiled for one hour to desorb the CO 2 gas.
The regenerated solution so obtained was transferred back to the absorber and cooled to 80° C. The apparatus was closed and evacuated until the liquid began to boil. At this point CO 2 gas was admitted. The amount of time taken for the solution to reabsorb 10, 15 and 20 l of CO 2 gas was measured, as well as the total amount of CO 2 gas reabsorbed in the process, designated as capacity to reabsorb.
The rich solution containing K 2 CO 3 , amine and amino acid was regenerated by boiling for an hour, and then was used for a phase-behavior study.
About 600 g of regenerated solution were charged into a 1-liter autoclave equipped with Herculite (trademark) window, reflux condenser and inlet and outlet for gases. The autoclave was brought to 121° C. while blowing a mixture containing 0.2% CO 2 gas and 99.8% He gas at about 0.2 liters/minute. When the outgoing gas had the same composition as the entering gas, equilibrium was reached. Only one phase was present in each case.
When the experiment was repeated, replacing pipecolinic acid with water, two liquid phases were present at equilibrium.
From the results of these tests, shown in Table 1, it can be seen that the rates of absorption and the solubilities of all non-sterically hindered diaminoalcohols tested were comparable to the absorption rate and solubility of CHPD (the preferred sterically hindered diamine in U.S. Pat. Nos. 4,094,957 and 4,112,050).
TABLE I__________________________________________________________________________ Time (min:sec) to absorb Capacity (liters indicated volume of CO.sub.2 Lean Amine* of CO.sub.2 reabsorbed) 10 1 15 1 20 1 Solubility__________________________________________________________________________N--cyclohexyl propanediamine** 30.0 0:53 1:30 2:21 one phaseN--(n-propyl)-N--(2-hydroxyethyl)-1,3 propanediamine** 31.6 0:51 1:25 2:08 one phaseN--(n-butyl)-N--(2-hydroxyethyl)-1,3-propanediamine** 32.7 0:56 1:35 2:19 one phaseN--(n-propyl)-N--(2-hydroxyethyl)-1,4-butanediamine 31.8 0:50 1:30 2:30 one phase__________________________________________________________________________ *In combination with pipecolinic acid **Controls
EXAMPLE 2
The following experiments were carried out to ascertain the stability of the diaminoalcohols herein under accelerated-simulated acid gas treating conditions.
Five standard lean solutions were prepared with the following ingredients:
7.4% by weight of the amine indicated in Table II
3.0% by weight of pipecolinic acid
26.1% by weight of KHCO 3 *
3.9% by weight of K 2 S**
59.6% by weight of water
A total of 5.4 g of each of these solutions was charged separately into five 10-ml, stainless-steel ampoules, which were each flushed with nitrogen gas and sealed. All of the ampoules were then immersed simultaneously into an oil bath at 140° C. and monitored each day by means of gas chromatographic analysis for the amount of original amine remaining in solution. Higher amounts of amine indicate less conversion to by-products and thus greater stability as well as non-volatility at temperatures of 140° C. The results are given in Table II.
TABLE II______________________________________ % of OriginalAmine Days at 140° C. Amine Remaining______________________________________CHPD* 7 <10N--(n-propyl)-N--(2-hydroxyethyl)-1,3- 7 <8propanediamine*N--(n-propyl)-N--(2- 2 66hydroxypropyl)-1,3- 5 44propanediamine* 12 16N--(n-propyl)-N--(3- 2 20hydroxypropyl)-1,3-propanediamine* 5 9N--(n-propyl)-N--(2- 2 80hydroxyethyl)-1,4- 5 73butanediamine 12 59______________________________________ *Controls
It can be seen that the diaminoalcohol of this invention, represented by the fifth amine in this table, exhibited superior stability as compared not only with CHPD, but also with homologous diaminoalcohols.
In summary, the present invention is seen to provide a class of non-sterically hindered diaminoalcohols which not only perform effectively in acid gas scrubbing processes but are also relatively non-volatile and stable to the acid gases present in the system.
While the invention has been described in connection with specific embodiments thereof, it will be understood that it is capable of further modification, and this application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains and as may be applied to the essential features hereinbefore set forth, and as fall within the scope of the invention. | Acidic gases containing carbon dioxide are removed from a normally gaseous mixture by absorbing CO 2 from the gaseous mixture with an aqueous solution comprising a basic alkali metal salt or hydroxide and an activator or promoter system for the salt or hydroxide which contains (i) at least one diaminoalcohol of the formula:
H.sub.2 N--(CH.sub.2).sub.4 --NRR'
wherein R and R' each independently represent a C 1 -C 6 alkyl group and either R or R' or both R and R' have a pendant hydroxyl group, and (ii) an amino acid, and desorbing at least partially the absorbed CO 2 from the aqueous solution. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Technical Field
[0002] This invention relates generally to heavy-duty flat wiper blade assemblies.
[0003] 2. Related Art
[0004] Heavy-duty flat wiper blade assemblies are known having a straight body mounting a rubber wiper element. In one known construction, the body is extruded from a plastic which is, in turn, reinforced by a metal stiffener to provide sufficient structural rigidity to the body, as shown in U.S. Pat. No. 3,107,384. In another known construction, the body is fabricated from a strip of steel which is bent into a generally U-shaped profile in cross-section and crimped along its length to the rubber wiper element to secure the wiper element. In this case, the flat steel body component is cut to length along with the wiper element prior to folding the flat steel over the wiper element.
[0005] Both such constructions are costly to manufacture and are limited in the features and advantages they can offer.
[0006] Heavy-duty flat wiper blade assemblies constructed according to the present invention overcome or greatly minimize the foregoing limitations of prior wiper blade assemblies.
SUMMARY OF THE INVENTION
[0007] A heavy-duty flat wiper blade assembly has a wiper element and an extruded metallic frame. The frame has a bottom channel with a slot and an upper channel separate from the bottom channel. The wiper element is disposed in the bottom channel and extends through the slot to make contact with a surface to be wiped. The upper channel is closed and may optionally be provided with a fluid inlet opening for receiving wiper fluid into the channel and a fluid outlet opening for discharging the wiper fluid from the upper channel and onto a surface to be wiped.
[0008] Additionally, a method for manufacturing a wiper blade is provided wherein a wiper element is slidably inserted into a bottom channel of an extruded metallic frame. The wiper element depends from the bottom channel and through a slot in the bottom channel to make wiping contact with a surface to be wiped. A wall of the bottom channel is then staked to fix the wiper element within the bottom channel. An optional method eliminates the staking step and installs a pair of end plugs into each end of the frame to releasably maintain the wiper element within the bottom channel.
[0009] Some advantages of the invention include providing for increased efficiencies in the manufacture and assembly of a heavy-duty wiper blade assembly by reducing the number of operations required to produce the wiper blade assembly, by reducing the scrap, by improving the handling of the wiper blade components during assembly and by reducing the time required for assembly, thus reducing the total costs of producing the wiper blade assembly.
[0010] Another advantage of the invention is the ability to utilize the closed upper channel as a passage for conveying wiper fluid from which the fluid may be dispensed directly on the surface to be wiped.
[0011] Another advantage of the invention is a reduction in the amount of material used in the wiper element.
THE DRAWINGS
[0012] These and other features and advantages of the present invention will become more readily appreciated when considered in connection with the following detailed description and appended drawings, wherein:
[0013] [0013]FIG. 1 is a perspective view of a wiper blade assembly showing a first preferred embodiment of the present invention;
[0014] [0014]FIG. 2 is a cross-sectional view taken generally along lines 2 - 2 of FIG. 1;
[0015] [0015]FIG. 3 is a front elevation view of a second embodiment of the present invention;
[0016] [0016]FIG. 4 is a fragmentary isometric view of the blade assembly of FIG. 3;
[0017] [0017]FIG. 5 is a cross-sectional view taken generally along lines 5 - 5 of FIG. 4;
[0018] [0018]FIG. 6 is a cross-sectional view taken generally along lines 6 - 6 of FIG. 4; and
[0019] [0019]FIG. 7 is an enlarged fragmentary elevation view, shown partly in section, of FIG. 4.
DETAILED DESCRIPTION
[0020] [0020]FIGS. 1 and 2 show a heavy-duty wiper blade assembly 10 constructed according to a first preferred embodiment of the present invention. The wiper blade assembly 10 has an extruded frame 12 having a bottom channel 14 that receives a wiper element 16 , and an upper channel 18 that is separate from the bottom channel 14 . The wiper element 16 is slidably received in the bottom channel 14 and is maintained in the bottom channel 14 by a protuberance or preferably a plurality of protuberances 20 .
[0021] The frame 12 of the wiper blade assembly 10 is extruded from a metallic material, such as aluminum, or any other extrudable metallic material. The finished frame 12 has a pair of ends 24 , 26 . The bottom channel 14 and upper channel 18 extend between the ends 24 , 26 .
[0022] The bottom channel 14 has slot 28 formed along the bottom channel 14 between the pair of ends 24 , 26 having openings 27 , 29 such that a bottom surface 30 of the bottom channel 14 preferably has a pair of opposing lips 31 , 32 extending generally toward one another, thus causing the bottom channel 14 to be generally C-shaped in cross-section, as shown best in FIG. 2.
[0023] The upper channel 18 of the frame 12 is a generally closed channel other than openings 34 , 36 at the ends 24 , 26 of the frame 12 , and an aperture 38 formed in a sidewall or opposing sidewalls 40 , 42 of the upper channel 18 between the ends 24 , 26 of the frame 12 .
[0024] The aperture 38 formed in the opposing sidewalls 40 , 42 of the upper channel 18 is preferably formed equidistant from either end 24 , 26 and receives a mounting pin (not shown) therethrough so that the wiper blade assembly 10 can be attached to a wiper arm (not shown).
[0025] As best shown in FIG. 2, the wiper element 16 has a crown portion 44 , a neck portion 46 , a bumper portion 48 , a hinge portion 50 , and a body portion 52 . The wiper element 16 is received by the bottom channel 14 by sliding the crown portion 44 of the wiper element 16 into one of the openings 27 , 29 of the bottom channel 14 . The pair of opposing lips 31 , 32 forming the bottom surface 30 of the bottom channel 14 extend generally inwardly toward the neck portion 46 such that they capture and releasably maintain the wiper element 16 . Though the wiper element 16 is releasably maintained within the channel 14 by the lips 31 , 32 , the wiper element 16 is still able to slide transversely within the bottom channel 14 .
[0026] Preferably, the crown portion 44 of the wiper element 16 conforms generally in shape to the bottom channel 14 . A bottom surface 53 of the crown portion 44 is preferably in mating contact with an upper surface 54 of the lips 31 , 32 such that the crown portion 44 is maintained within the bottom channel 14 during assembly 10 . The neck portion 46 of the wiper element 16 depends from the crown portion 44 and passes between the lips 31 , 32 of the frame 12 and joins the bumper portion 48 of the wiper element 16 . The bumper portion 48 of the wiper element 16 contacts the bottom surface 30 of the lips 31 , 32 . The wiper element 16 can be secured against relative sliding movement within the channel 14 by staking a sidewall or sidewalls 40 , 42 of the bottom channel 14 , such that a plurality of protuberances 20 extend laterally inwardly into gripping engagement with the crown portion 44 of the wiper element 16 . As shown in FIG. 1, preferably two protuberances 20 are staked adjacent each end 24 , 26 of each side-wall 40 , 42 of the frame 12 . However, it should be recognized that any number of protuberances 20 may be staked depending on the requirements of the wiper blade application.
[0027] FIGS. 3 - 7 show an alternative embodiment of a wiper blade assembly of the invention generally at 110 . The same reference numerals are used to designate like features to those of the first embodiment, but are offset by 100. The assembly 110 includes an upper channel 118 in which a pair of end plugs 22 , 23 are installed. The channel 118 communicates with a source of pressurized wiper fluid (not shown) through one of the end plugs 22 , 23 . The wiper fluid can travel through and be dispensed from the upper channel 118 directly onto the surface to be wiped by the wiper blade assembly 110 . Also, the wiper element 116 is preferably releasably maintained in the bottom channel 114 by a bottom portion 56 of the pair of end plugs 22 , 23 , thus enabling the wiper element 116 to be quickly and easily replaced when needed. It should be recognized however, that a staking operation could be used here as performed in the first preferred embodiment.
[0028] The pair of end plugs 22 , 23 are preferably sized so that they can be press fit into the openings 134 , 136 at the ends 124 , 126 of the upper channel 118 such that they have an interference fit or other suitable mechanical retention (e.g. latches), and create a generally fluid tight seal therein. The end plugs 22 , 23 are shaped to have a plug portion 58 that fits within the upper channel 118 , and a face portion 60 that remains in mating contact with an end 124 , 126 of the frame 112 . One end plug 22 preferably has a through hole 62 such that a hose 64 can be connected in the through hole 62 of the end plug 22 to provide for communication of fluid between the upper channel 118 and the source of pressurized wiper fluid. The wiper fluid can then be received within the upper channel 118 of the wiper blade assembly 110 and be dispensed from the upper channel 118 through a nozzle 64 and directed onto the surface to be wiped by the wiper blade assembly 110 . It should be recognized however, that the hose 64 could be received in an opening anywhere along the upper channel 118 between the two ends 24 , 26 of the upper channel 118 , and not through one of the end plugs 22 , 23 in the pair of ends 124 , 126 of the frame 112 .
[0029] The end plugs 22 , 23 preferably extend downwardly from the upper channel 118 so that the face portion 60 blocks or covers at least a portion of the bottom channel 114 . With at least one end plug 22 , 23 removed from the bottom channel 114 , the wiper element 116 can be slidably received within the bottom channel 114 , and the end plug or end plugs 22 , 23 can then be press fit into the bottom channel 114 . The face portions 60 of the plugs 22 , 23 then releasably maintain the wiper element 116 within the bottom channel 114 . If the wiper element 116 needs replacing, one of the end plugs 22 , 23 can simply be removed to slidably remove the wiper element 116 from the bottom channel.
[0030] As best shown in FIG. 6, another opening 66 in one of the side walls 40 , 42 of the upper channel 118 has the nozzle 64 received therein. The nozzle 64 is fixed in the opening 66 of the upper channel 118 such that the nozzle 64 is maintained in sealing engagement with the opening 66 . The nozzle 64 has a through hole 68 that is formed to dispense wiper fluid from the upper channel 118 such that the wiper fluid exits preferably in a desired spray pattern. The nozzle 64 is shown here to be generally equidistant between the two ends 24 , 26 of the upper channel 118 . It should be recognized however, that the opening 66 used to receive the nozzle 64 can be placed anywhere along the length between the two ends 24 , 26 of the upper channel 118 , as best suited for the application. It should also be recognized that any number of nozzles 64 can be employed within the sidewalls 140 , 142 to insure adequate coverage of wiper fluid on the surface to be wiped by the wiper blade assembly 110 .
[0031] As best shown in FIG. 5, a grommet 70 is installed in the aperture 138 to create a fluid tight seal between the mounting pin and the upper channel 118 to prevent any wiper fluid from leaking between the aperture 138 and the mounting pin. Ends 72 , 74 of the grommet 70 are formed with radially enlarged flanges 76 , 78 for securing and sealing the grommet 70 within the aperture 138 . The grommet 70 has a tubular body passing through the upper channel 118 , defining a through hole 80 for accommodating the mounting pin (not shown). Other suitable means for creating a seal between the aperture 138 and the mounting pin to prevent wiper fluid from exiting the aperture 138 is contemplated by this invention, such as applying a coating to the walls of the aperture 138 or to the mounting pin so that the coating provides a fluid-tight seal.
[0032] Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described. The invention is defined by the claims. | A heavy-duty flat wiper blade assembly has a wiper element and an extruded metallic frame. The frame has a bottom channel with a slot traversing its length in which the wiper element is maintained. The wiper element extends through the slot and outwardly from the bottom channel to make contact with a surface to be wiped. The frame has a closed upper channel that may include a fluid inlet opening for receiving wiper fluid into the channel and a fluid outlet opening for discharging the wiper fluid from the upper channel onto a surface to be wiped. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention, in general, relates to a front-loading washing machine and, more particular, to a front-loading washing machine of the kind provided with a housing with a substantially cylindrical sudsing container resiliently suspended therein and a cylindrical drum rotatably arranged within the sudsing container, the front walls or caps of the drum and of the sudsing container as well as the front of the housing being provided with substantially circular and coaxially disposed loading openings, and with an elastomeric folding bellows which sealingly connects the circumferential rim of the openings in the front of the housing and in the sudsing container and which is provided with a crease facing the common axis, and with an at least partially elastomeric extension protruding into the intermediate space between the crease and the rim of the loading opening of the drum, the rim, the upper end of the extension and a part of the crease being at least partially aligned in the axial direction. The invention also relates to a method of manufacturing such a washing machine.
[0003] 2. The Prior Art
[0004] A washing machine of the kind referred to is known from DE 90 15 420 U1. In washing machines of this type, the crease is provided for absorbing oscillations caused by imbalances during spinning and leading to a relative movement or displacement between the sudsing container and the housing. In order to prevent wear of the folding bellows in the area of its crease as a result of friction at the rotating rim of the loading opening of the drum (drum rim), a sufficiently large spacing between the crease and the drum rim is required. This may lead to laundry extending over the rim of the drum slipping deeply into the gap and tearing as a result of the increased friction between the rotating drum and the stationary sudsing container. The extension shown in FIG. 2 of DE 90 15 420 U1 serves as a laundry deflector by reducing the gap between the rim of the drum and the gap, thereby preventing laundry from being pulled into the gap. The friction of the extension at the drum is not critical since its wear does not adversely affect the sealing of the folding bellows.
[0005] German Patent DE 102 37 017 B3 discloses a washing machine which in the area of the upper apex of the loading opening of the drum is provided with a laundry deflector. The laundry deflector extends into the space between the crease of the elastomeric folding bellows and the rim of the loading opening of the drum. By an L-shaped bend in the direction of the interior chamber of the drum, any pulled-in laundry is securely guided out of the crease or gap, as the case may be, and falls back into the drum. To this end, a deformation is required in the circumferential rim of the folding bellows in the area of the laundry deflector so that the laundry deflector may extend outwardly between the folding bellows and the rim of the loading opening of the drum. Hence, this area of the folding bellows is subject to premature wear.
[0006] It has, however, been found that the function of the deflector principle requires the gap to be adjusted with great precision which, in turn, requires a structurally stable hammer. Narrowing or contractions of the gap lead to wedging or squeezing in of laundry tips and, therefore, to excessive wear of the laundry. These conditions may be satisfied with relative ease in household laundry machines provided with loading openings of a diameter up to about 30 cm. Larger openings not only result in a reduced structural stability of the extension, but during assembly the adjustment of the gap becomes more difficult and complex as the diameter of the folding bellows increases.
OBJECTS OF THE INVENTION
[0007] It is, therefore, an object of the invention to provide a front-loading washing machine of the kind referred to supra in which maintenance of the desired gap dimension between the extension and the rim of the drum during assembly is simplified.
[0008] Moreover, it is an object of the invention to provide a method of manufacturing a washing machine of the kind referred to supra, in which it is simple to maintain the desired gap between the extension and the rim of the drum.
SUMMARY OF THE INVENTION
[0009] In accordance with the invention, the object is accomplished by a front-loading washing machine the front wall of the sudsing container of which is provided with at least one bracket extending in the direction of the common axis and by the extension being provided with a fastening element mounted on the bracket for axial movement relative thereto.
[0010] The method in accordance with the invention is accomplished by aligning the extension at a predetermined distance from the rim of the loading opening of the drum after the retaining element has been placed on the bracket.
[0011] Other and advantageous features of the washing machine in accordance with the invention will in part be obvious and will in part become apparent as the description unfolds.
[0012] The structure in accordance with the invention of the sudsing container front wall in the area of the rim of its loading opening and the mounting of a moveable retaining element at the extension make possible, during assembly, a very simple yet exact alignment relative to the rim of the drum. In an advance assembly operation, the retaining element may be connected to the resilient or elastic portion of the extension.
[0013] Advantageously, the bracket is of annular configuration.
[0014] In a further advantageous embodiment, the retaining element is structured as a slotted receiving element.
[0015] In an advantageous embodiment, the retaining element is structured as a support ring which in its mounted state at least partially engages the bracket or brackets, as the case may be. In this manner, it is easy to move the retaining element relative to the bracket.
[0016] In a further advantageous embodiment, the bracket and the retaining element are provided with matching threads. In this manner, following its adjustment the dimension of the gap remains constant over the entire circumference of the extension or rim of the drum because jamming between retaining element and bracket is prevented.
[0017] It is also advantageous angularly to bend the retaining element so that an arm disposed normal to the bracket will support the extension which is of T-shaped cross-section. In this manner, the extension may be fabricated in a simple manner, particularly if the extension consists of an angular plastic core and an elastomeric coating.
[0018] It is possible integrally to mold the elastomeric portion of the extension on the folding bellows. Alternatively, the extension may be structured as a separate component which makes it possible to structure its elastomeric portion harder than the folding bellows. The greater hardness results in reduced wear and tear and in a greater structural stability. Moreover, the assembly is simplified. In connection with sudsing containers provided with a plastic front wall the mounting of the extension and of the folding bellows is simplified by a clamping rod for the folding bellows is molded in addition to the bracket.
[0019] In a further advantageous embodiment, the extension with a margin angled towards the sudsing container consists of a hard plastic or of a hard elastomeric component with which the folding bellows of soft elastomeric material is integrally formed. The margin angled in the direction of the sudsing container and which circumscribes the bracket of the sudsing container is attached by a circumferential clamping ring.
[0020] To prevent the extension from axially slipping on the bracket of the sudsing container, the angled bracket and the retaining element of the sudsing container may in their engagement section be of toothed, undulating or saw-tooth or similar interlocking configuration.
DESCRIPTION OF THE SEVERAL DRAWINGS
[0021] The novel features which are considered to be characteristic of the invention are set forth with particularity in the appended claims. The invention itself, however, in respect of its structure, construction and lay-out as well as manufacturing techniques, together with other objects and advantages thereof, will be best understood from the following description of preferred embodiments when read in connection with the appended drawings, in which:
[0022] FIGS. 1, 2 , 3 and 4 are schematic views of partial sections of washing machines in accordance with the invention in the lower portion of the loading openings; and
[0023] FIGS. 1 a, 1 b, 1 c and FIGS. 2 a, 2 b, 2 c depict the extension and parts thereof in detailed views.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] As is well known, a washing machine is provided with a housing within which a substantially cylindrical sudsing container is resiliently suspended. Within the sudsing container, a drum is journaled for rotations, the axis of rotation of the drum and the axis of symmetry of the sudsing container coinciding as substantially common axis 6 . In the examples shown, the common axis 6 extends horizontally. It may, however, also be slightly inclined (not shown) towards the rear of the housing. The front walls 2 and 3 , hereinafter sometimes referred to as caps, of the drum and of the sudsing container are provided with circular loading openings. The rim of the front wall 3 of the drum is bent about 45° relative to the exterior of the drum and is curled in its outer marginal section. This section will hereafter be referred to as drum rim 4 . The front cap 2 of the sudsing container may be made of plastic (fiber-glass reinforced polypropylene) are ferrous sheet metal. In either case, the rim of the front cap 2 facing the opening is provided with an annular bracket 5 angled by 90°. In terms of its function to be described, it is important to note that the bracket in its marginal section depicted to the right of the drawings is not provided with any flange or the like; it is merely extending in the direction of the axis 6 . In the case of a plastic sudsing container, the bracket 5 is connected by injection molding. In a sheet-metal sudsing container the bracket is formed by bending the margin. A loading opening is also provided in the front wall 1 of the housing which is sealed in a liquid-proof manner by a door not shown in the drawings. The margin of every one of the three loading openings includes a circular surface disposed vertically and symmetrically with respect to the axis 6 .
[0025] To prevent water from escaping from the sudsing container into the interior of the housing, the sudsing container cap 2 and the front wall 1 of the housing are connected in the marginal area of their loading openings by a folding bellows 7 made of EPDM of a Shore A hardness of 35 to 40. As seen in FIG. 1 , a clamping ring 8 is formed on the plastic sudsing container cap 2 for accepting the rim 9 of the folding bellows 7 facing the sudsing container which is thereafter affixed to the ring by a clamping ring 10 . FIGS. 2 and 3 depict embodiments in which the folding bellows 7 is affixed to the lower surface of a bracket 5 . In the area of the rim 11 of the loading opening the front wall 1 of the housing is flanged so that the rim 12 of te folding bellows 7 facing the housing may also be attached by a clamping ring 13 .
[0026] A laundry deflector structured as an extension 15 is inserted into the gap formed between the drum rim 4 and the crease 14 of the folding bellows 7 directed towards the axis 6 . The upper end 15 of the deflector extends to the height of a connecting line between the drum rim 4 and the upper margin of the crease 14 , so that these three components are at least in part axially aligned. At its other end, the extension 15 is provided with a retaining element at least a part of which is extending in the direction of the bracket 5 . FIG. 1 depicts a variant in which the retaining element is structured as an angular support ring 17 . Its horizontal arm 18 at least partially engages the bracket 5 ; its vertical arm 19 supports an elastomeric component 20 of T-shaped cross-section and made of EPDM. By means of a slide connection ( FIG. 1 a ) , a threaded connection 21 ( FIG. 1 b ) or a toothed snap connection 22 ( FIG. 1 c ), the support ring may thus be moved in the direction of the axis 6 , and the distance s between the upper end ' 6 of the extension 15 and the drum rim 4 may thus be adjusted. Following alignment of the extension 15 , the support ring 17 may be permanently affixed to the bracket 5 by a welded connection 23 ( FIG. 1 a , a safety screw 23 ( FIG. 1 b ) or clamping ring 25 ( FIG. 1 c ). Any combination of the alignment of the gap s and the permanent attachment is possible. In the case of a permanent attachment by a welding connection, the bracket 5 and the support ring 17 should consist of the same material.
[0027] FIG. 2 and FIGS. 2 a , 2 b and 2 c depict embodiments in which the retaining element is structured as a slotted receptacle 26 and is connected to the extension. In this case, too, the previously mentioned ways of adjusting the gap and permanent mounting on the bracket may be freely varied. In some examples ( FIGS. 2, 2 a , 2 b ), the extension 15 consists of a plastic core 27 with an elastomeric coating 28 . FIG. 2 c depicts a one-piece extension 15 made of an elastomeric material, e.g. EPDM. All variants are provided with an integral deflector lip 29 for preventing small articles (coins, nails, etc.) inadvertently left in the pockets of laundry from moving into the area between the drum and the sudsing container where they may damage the output section of the sudsing container.
[0028] In the embodiments of FIGS. 1, 1 a , 1 b as well as in the embodiments of FIG. 2 c it was shown to be useful, to use a material for the elastomeric component 20 or the coating 27 of the extension 15 which is of greater hardness than the folding bellows 7 . This ensures greater structural stability and abrasion resistance and, in turn, a constant gap dimension s over the entire life of the washing machine. In these embodiments, a covering ring of chromium steel may be placed on the upper end 16 of the extension 15 (not shown).
[0029] In the variant shown in FIG. 3 , the elastomeric component of the extension is molded onto the folding bellows. This component is provided with a receiving slot 30 in which an angled support ring 17 (see FIG. 1 ) is supported. It is thus possible after aligning the extension 15 to attach the extension 15 and the folding bellows with but one clamping ring 10 . This requires accepting the disadvantage of the extension 15 also consisting of the material of lower hardness which must be used for manufacturing the folding bellows 7 .
[0030] FIG. 4 depicts an embodiment in which the extension 15 a is unitary with the folding bellows 7 a , the extension 15 a consisting of a hard material and the folding bellows 7 a consisting of a soft material, e.g. of a soft elastomeric material. It may be fabricated, for instance, in a two-component injection molding process. Alternatively, the folding bellows 7 a made of a soft material may be adhesively connected or welded to the extension 15 a . At its lower surface the extension 15 a is bent 9 a at an angle in the direction of the sudsing container and is pushed over the bracket 5 of the sudsing container. The angled portion 9 a is attached to the bracket 5 by a clamping ring 10 . The extension 15 a is thus affixed to the bracket 5 . In order to prevent axial movement of the extension 15 a or during assembly to arrest it in a preferred position, the angle portion 9 a and the bracket 5 in the area of contact are provided with an interlocking undulation 21 a , triangular teeth 22 a ( FIG. 4 a ) or a saw-tooth arrangement 22 b ( FIG. 4 b ). | A front loading washing machine with a housing, a sudsing container and a drum having openings in substantially coaxial alignment, the sudsing container and the housing being connected by a folding bellows surrounding marginal portions of their respective openings and provided with a crease. An extension protruding into a gap between the crease and the rim of the opening of the drum, with the rim, the upper end of the extension and a portion of the crease being in at least partial coaxial alignment. | 3 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to the field of heat transfer devices. More specifically, the present invention relates to a fan retainer clip that allows the field removal of a defective fan from a heat transfer device without disturbing the heat transfer device or the component it is cooling.
BACKGROUND OF THE INVENTION
[0002] The electronics and computer industries are constantly expanding and pushing the limits of both performance and quality. The increased speeds and reduction in component size requirements have also required increased performance from cooling systems to prevent product degradation due to high performance temperatures. In general, heat transfer systems transfer heat from a heat-generating source to the surrounding air by the use of a combination of fans and heat transferring fins or heat sinks. As used herein, and in the appended claims the terms “heat transfer device” or “heat sink” will be understood to refer to all such devices that transfer heat from components using any combination of fans, fins or similar members.
[0003] Generally, heat transfer systems use a combination of conduction and convection or forced convection to transfer heat from heat generating components. A heat-producing component is placed in contact with the base of the heat transfer device. The heat transfer device is made of a material that readily conducts or transfers thermal energy through contact. Examples of such materials include aluminum and copper. The heat from the heat producing electronic device is transferred through the conductive base to the rest of the heat transfer device. The base of the heat transfer device is formed with a number of fins or other shaped extrusions that maximize surface area on the opposing side of the contact surface. The transferred thermal energy is then transferred from the conductive base to the fins. The thermal energy is then transferred from the large surface area of the fins to the surrounding medium (air or liquid) through convection. Convection is the flow of thermal energy from a solid to a liquid or gaseous medium. In most heat transfer devices, the use of stagnant air is not sufficient so the convection (or transfer of heat energy from the solid to the liquid/gaseous medium) is increased through forced convection. Forced convection includes the use of a fan or other transfer device to force the liquid/gaseous medium over the increased surface area of the fins. This increased flow of the liquid/gaseous medium increases the transfer of heat energy from the fins to the cooling medium thereby increasing the rate of cooling of the heat-producing component.
[0004] During the heat transfer process, the circulation of the air, and therefore the rate of transfer of the heat energy from the fins, is dependant upon the performance of the fan. If the fan is under performing or malfunctioning it may effectively reduce the efficiency of the heat transfer device and damage the electronic heat-producing component by allowing it to overheat. When the fan of a heat transfer device is malfunctioning, a great need arises to immediately replace it. Replacement of a faulty fan produces a number of problems due to the current manner of securing the fan to the base of the heat transfer device.
[0005] [0005]FIG. 6 illustrates a conventional heat transfer system. As shown in FIG. 6 and described in U.S. Pat. Nos. 6,345,664 and 6,351,044 (which are incorporated herein by reference), a cooling fan ( 50 ) is generally attached to the base ( 44 ) of a heat transfer device by adhesives ( 60 ). The fan ( 50 ) includes fan blades ( 52 ) that, when rotated, force air or other cooling medium over a set of fins ( 42 ). Power for the fan ( 50 ) is provided through a wire ( 56 ). The prior solution of using adhesive ( 60 ) to attach the fan ( 50 ) to the heat sink is not field-repairable and involves complicated heat sink removal procedures in the case of a failed heat sink fan. Additionally, the complexity of the removal procedures increases the amount of down time needed to replace a faulty fan and usually disturbs both the functioning of the heat producing component and the heat transfer device.
[0006] Other prior art solutions involve screwing the fan to the heat transfer device by placing screws through the fan housing. In many cases, however, there is no fan housing; rather the fan motor needs to be directly attached to the fin base of the heat transfer device. Screwing the fan to the base would be possible with a number of plastic fan designs, but the screw heads would be difficult to reach without disturbing the heat transfer device, and it is unlikely that fan vendors will be willing to incur increased costs by changing the design of their fan housings.
[0007] U.S. Pat. No. 6,109,340; U.S. Pat. No. 5,484,013; and U.S. Pat. No. 5,615,998 (incorporated herein by reference) demonstrate attempted solutions to the problems associated with connecting the fan by adhesives. In U.S. Pat. No. 6,109,340, the fan is integrally connected to the fan housing which is then designed to be easily removed and attached to the heat transfer device. However, by integrally connecting the fan to the housing it becomes impossible to replace the fan without replacing both the fan and the fan housing. This increases both replacement costs and manufacturing costs of the fan due to increased complexity of molds required to form the fan and housing as well as increasing the material required to manufacture the part.
[0008] Another possible solution to the removal problems associated with bonding the cooling fan with adhesives is addressed by U.S. Pat. No. 6,343,012 and U.S. Pat. No. 6,343,012. (incorporated herein by reference). In these patents, a retaining clip is affixed to the heat transfer device containing female threads. The fan is then manufactured with corresponding male threads integrally connected to the base of the cooling fan. To assemble the invention the male threads are affixed to the female threads of the retaining clip. While the fan is manufactured independently of the retaining clip, overall manufacturing costs of the fans are increased due to the increased complexity of the threaded base. Additionally, it is both difficult and time consuming to rotatably release a fan in compact situations such as cylindrically shaped heat transfer devices.
SUMMARY OF THE INVENTION
[0009] One embodiment of the present invention provides a fan-securing device for securing a fan to a heat transfer device that allows for the rapid removal of the fan without disturbing the remainder of the heat transfer device. The fan-securing device includes a base, a fastener for securing the body base to the heat transfer device, and compression tabs for securing the fan to the base.
[0010] In another embodiment, the present invention provides a heat transfer device that includes a heat transfer base for contacting with a heat producing component, fins protruding from the heat transfer base for conducting heat from the heat transfer base; a fan for transferring air through the fins; and a fan-securing device that includes a body, a hole and compression tabs, where the tabs come in contact with the base of the fan thereby securing the fan in the fan-securing device.
[0011] In another embodiment, the present invention provides a fan-securing device for securing a fan to a heat transfer device that allows for the rapid removal of the fan without disturbing the remainder of the heat transfer device. The fan-securing device includes a body, a securing means for securing the body to the heat transfer device, and a retaining means for retaining the fan to the body, the retaining means being releasable.
[0012] In another embodiment, the present invention provides a method for securing a fan to a heat transfer device that allows for the rapid removal of the fan without disturbing the remainder of the heat transfer device by attaching a fan-securing device having compression tabs to the base of the heat transfer device, and pushing the fan into the fan-securing device such that the compression tabs securely attach the fan to the fan-securing device.
[0013] Additional advantages and novel features of the invention will be set forth in the description which follows or may be learned by those skilled in the art through reading these materials or practicing the invention. The advantages of the invention may be achieved through the means recited in the attached claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The accompanying drawings illustrate preferred embodiments of the present invention and are a part of the specification. Together with the following description, the drawings demonstrate and explain the principles of the present invention. The illustrated embodiments are examples of the present invention and do not limit the scope of the invention.
[0015] [0015]FIG. 1 shows an exploded perspective view of an embodiment of a fan-securing apparatus according to principles of the present invention.
[0016] [0016]FIG. 2 shows an assembled perspective view of an embodiment of the fan-securing apparatus in conjunction with a heat transfer device.
[0017] [0017]FIG. 3 shows a perspective view of an embodiment of the present invention secured to the heat transfer device in conjunction with a cooling fan.
[0018] [0018]FIG. 4 shows a perspective view of an embodiment of the present invention fully assembled.
[0019] [0019]FIG. 5 is a cross-sectional view of an embodiment of a compression tab according to principles of the present invention.
[0020] [0020]FIG. 6 illustrates a heat dissipating apparatus according to the prior art.
[0021] Throughout the drawings, identical reference numbers designate similar, though not necessarily identical, elements.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0022] [0022]FIG. 1 illustrates an embodiment of a fan-securing device according to the principles of the present invention. As shown in FIG. 1, such a fan-securing device ( 10 ) preferably includes a base or body ( 28 ), a recessed receiver member ( 30 ), a hole in the middle of the recessed receiver member (not shown), a side housing ( 12 ), compression tabs ( 18 ) with protruding pawls ( 18 a ) and a compression tab neck ( 18 b ), a spring retaining clip ( 20 ), a wire guard ( 26 ) with compression legs ( 24 ) and release tabs ( 22 ), a spring ( 16 ), and a screw ( 14 ).
[0023] [0023]FIG. 2 illustrates how an embodiment of the fan-securing device ( 10 ) is secured to a heat transfer device ( 40 ). Heat transfer device ( 40 ) preferably includes a base ( 44 ) and a cylindrically-shaped set of fins ( 42 ). When securing the fan-securing device ( 10 ) to the heat transfer device ( 40 ), a hole is first tapped into the heat transfer device ( 40 ). This hole is for receiving the screw ( 14 ) used to secure the fan-securing device ( 10 ). The fan-securing device ( 10 ) is lowered onto the heat transfer device ( 40 ) lining up the hole (not shown) in the center of the recessed receiver member ( 30 ) with the tapped hole in the heat transfer device ( 40 ). Once the holes are lined up, the screw ( 14 ) is threaded into the tapped hole thereby securing the base ( 28 ) of the fan-securing device ( 10 ) to the base ( 44 ) of the heat transfer device ( 40 ).
[0024] [0024]FIG. 2 illustrates that a portion of a fin may be removed from the set of fins ( 42 ) on the heat transfer device base ( 44 ) to form a gap ( 45 ). This gap ( 45 ) provides clearance for the wire guard ( 26 ) when the fan-securing device ( 10 ) is installed. Once the base ( 28 ) of the fan-securing device ( 10 ) has been secured to the base ( 44 ) of the heat transfer device ( 40 ), the spring ( 16 ) is inserted into the recessed receiver member ( 30 ). Preferably, the spring ( 16 ) is a conical snap-in spring, which fits tightly over the head of the screw ( 14 ). The interference fit between the conical spring ( 16 ) and the head of the screw ( 14 ) prevents movement or loss of the screw ( 14 ). Additionally, some embodiments of the invention may include a spring retaining clip ( 20 ), which protrudes from the side of the recessed receiver member ( 30 ). Once the spring ( 16 ) is inserted into the recessed receiver member ( 30 ), the protruding nature of the spring retaining clip ( 20 ) prevents the spring ( 16 ) from exiting.
[0025] Once the fan-securing device ( 10 ) is attached to the base ( 44 ) of the heat transfer device ( 40 ), the fan ( 50 ) may be inserted as demonstrated by FIGS. 3 and 4. FIG. 3 shows the fan ( 50 ) as it is about to be installed into the fan-securing device ( 10 ). To secure the fan ( 50 ), The fan is simply pushed down into the center of the fan-securing device ( 10 ). As the fan ( 50 ) is pushed towards the base ( 28 ) of the fan-securing device ( 10 ) the spring ( 16 ) is compressed.
[0026] When the fan ( 50 ) is inserted in the fan-securing device ( 10 ) to the base ( 28 ), the compression tabs ( 18 ) are able to secure the fan ( 50 ). The protruding pawls ( 18 a ) located on the fan side of the compression tabs ( 18 ) engage with a recessed groove ( 54 ) on the base of the fan ( 50 ). FIG. 4 illustrates the fan ( 50 ) fully installed in the fan-securing device ( 10 ) and the heat transfer device ( 40 ).
[0027] [0027]FIG. 5 illustrates an embodiment of the present invention where the protruding pawls ( 18 a ) engage with the recessed groove ( 54 ) of the fan ( 50 ). Once the pawls ( 18 a ) have engaged, they secure the fan ( 50 ) by preventing it from moving vertically. Additionally, the side housing ( 12 ) prevents the fan ( 50 ) from translational movement thereby securing it in the fan-securing device ( 10 ). The spring ( 16 ) also pushes the fan ( 50 ) upward against the pawls ( 18 a ). This ensures a tight and secure fit between the pawls ( 18 a ) and the fan ( 50 ) and compensates for any dimensional variability in the assembly components.
[0028] The recessed groove ( 54 ) can be provided in several ways. In one embodiment, the groove is formed by the interface between two different pieces, 1) the fixed motor base of the fan and 2) the fan rotor. In this embodiment, the “groove” ( 54 ) is actually a natural gap between these two components, the motor base and fan rotor. The pawls ( 18 a ) grab onto the non-rotating piece, the motor base. In alternative embodiments, the groove ( 54 ) may be an interface between components of the fan or an actual groove carved in an exterior housing or other component of the fan.
[0029] Upon securing the fan ( 50 ) to the fan-securing device ( 10 ), the fan wires ( 56 ; FIG. 4) are inserted to the wire guard ( 26 ; FIG. 4). The wires ( 56 ) are inserted into the compression legs ( 24 ), which compress the fan wires ( 56 ). By securing the fan wires ( 56 ), the compression legs ( 24 ) prevent the fan wires ( 56 ) from interfering with the fan blades ( 52 ) and from chafing against the sharp fin edges ( 42 ).
[0030] To remove the fan ( 50 ) from the heat transfer device ( 40 ), the compression tabs ( 18 ) are pushed one at a time with a small screwdriver or other instrument. When the compression tabs ( 18 ) are pushed downward the neck of the compression tabs ( 18 b ) bend retracting the protruding pawl ( 18 a ) from the recessed groove ( 54 ) in the fan ( 50 ). When the protruding pawl ( 18 a ) is retracted enough to reduce the interference between the protruding pawl ( 18 a ) and the recessed groove ( 54 ), the spring ( 16 ) ejects the fan ( 50 ). The fan wires ( 56 ; FIG. 4) are then released by applying pressure in opposing directions to the release tabs ( 22 ) on the wire guard ( 26 ; FIG. 4). The pressure spreads the compression legs ( 24 ) thereby widening the gap allowing for the removal of the fan wires ( 56 ).
[0031] It will be appreciated by those of skill in the art, that the function of the recessed groove ( 54 ) could alternatively be performed by a number of configurations. One alternative configuration includes protruding notches on the base of the fan ( 50 ), each of which corresponds to a compression tab ( 18 ). When the protruding notch is inserted past the compression tab ( 18 ), the interference with the protruding pawl ( 18 a ) is again formed, securing the fan ( 50 ). Other securing configurations may include interference posts in conjunction with a hole or additionally a compression ring could be used to secure the fan ( 50 ).
[0032] It will also be appreciated by those of skill in the art, that the fan-securing device ( 10 ) doesn't have to be secured to the base of the heat transfer device ( 40 ) by the screw ( 14 ). An adhesive or any other securing means known in the art could secure the fan-securing device and still perform the desired function of allowing easy and quick removal of a malfunctioning fan.
[0033] Moreover, it will be appreciated by those of skill in the art that the invention could be made of a number of materials including, but not limited to, plastic, aluminum, or copper. Moreover, a number of processes may be employed to form the invention including, but not limited to, injection molding, thermo molding, pressing, stamping, casting, or milling.
[0034] In conclusion, the present invention, it its various embodiments, reduces the assembly and removal time of a fan ( 50 ) associated with a heat transfer device ( 40 ). Moreover, the invention is designed so that a fan snaps into the fan-securing device ( 10 ) and is easily removable, allowing replacement of a failed fan ( 50 ) without disturbing the heat transfer device ( 40 ) or the component it is cooling.
[0035] The preceding description has been presented only to illustrate and describe the invention. It is not intended to be exhaustive or to limit the invention to any precise form disclosed. Many modifications and variations are possible in light of the above teaching.
[0036] The preferred embodiment was chosen and described in order to best explain the principles of the invention and its practical application. The preceding description is intended to enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as is suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims. | A fan-securing device secures a fan to a heat transfer device that allows for the rapid removal of the fan without disturbing the remainder of the heat transfer device. The fan-securing device includes a base, a fastener for securing the body base to the heat transfer device, and compression tabs for securing the fan to the base. | 7 |
FIELD OF THE INVENTION
The invention generally relates to the field of multiprocessing systems and architecture. More specifically, the invention has to do with synchronizing time representations, or "clocks," maintained by various processors in a multiprocessing network.
BACKGROUND OF THE INVENTION
In many applications, computers and processors maintain some form of real time for reference and sequencing purposes, and for the purpose of synchronization of activities with other computers or processors. In particular, in network and multiprocessing architectures, such as that shown in FIG. 11, time synchronization between network nodes 100 is important. The common terminology is to say that a node maintains a "clock", and that "clock synchronization" is the process by which the nodes maintain the time values of their clocks.
Generally, such devices maintain a register or other hardware or software structure which contains a representation of real time. This time representation can be either a political time (such as Universal Time, Greenwich Mean Time, Eastern Standard Time, etc.) or some suitable form of logical time. In either case, the device maintaining the time representation updates the time internally on a real time basis. For instance, a processor might have a hardware oscillator which provides a signal at a known real time interval, measured in terms of system hardware clock cycles. Responsive to the signal, the processor updates its internal time in accordance with the known real time interval between signals.
In addition to maintaining and updating time internally, a processor or network node synchronizes its internal time with an external reference time source 102. A processor which has been synchronized to an external time source measures time in accordance with its internal hardware clock, which operates at a known frequency. Since the hardware clock frequency is inevitably not perfectly accurate, as time goes by the internal time maintained by a processor diverges from the external time with which the processor was previously synchronized. This time divergence is sometimes called "clock drift". Typically the processor's time drifts away from the external time as a linear function of elapsed time since synchronization. To prevent the clock drift from getting too large, from time to time the processor resynchronizes its internal time with the external reference time.
In general, a time is represented, not as a single time value, but rather as an interval, such as a time value, plus or minus an error bound value. A time expressed as an interval is considered to be "correct" if a reference time falls within that interval. For instance, if the time according to an external reference is 12:00:00, then a time representation of 11:59:50±0:00:15, which runs from 11:59:35 to 12:00:05, would be considered correct.
Because of clock drift, a time representation must gradually increase the error bound in order to remain correct. Eventually, the error bound grows large enough to be disadvantageous or unsuitable for operation. Then, a resynchronization procedure is executed, and a new time is adopted. In particular, the resynchronization procedure produces a new, smaller error bound to go with the new time.
Various arrangements may be used for providing a reference time source. For instance, in a network comprising a plurality of nodes, one of the nodes serves as a repository of a reference time. All other nodes of the network are synchronized with that node's time. Another time synchronization method involves reception of a reference time from a time source external to the network. Time services exist, which provide accurate time information for various purposes, including computer or network synchronization. One well known time service is WWV, which broadcasts a Universal Time signal. WWV and other similar time sources may be used to provide time synchronization to computers and processors.
As described above, a processor which is synchronized with such a time source gradually drifts out of synchronization. Also, time sources such as WWV occasionally introduce "leap seconds" to synchronize their time with the motions of the planet Earth. To prevent error from accumulating due to drift and leap seconds, it is particularly desirable that a processor synchronize itself with an external time source from time to time in the normal course of its operation.
In architectures in which a predetermined node is a reference time source, or in which an external reference time source, such as a subscription time service, is coupled through a suitable communication link or interface 104 to a predetermined node of a network, the predetermined node may be characterized as a master node. In order for the master node to synchronize other nodes, the master node conventionally must know which other nodes it is responsible for updating, so that it can direct appropriate time update messages to those nodes. The master node sends synchronization messages to other nodes coupled to the network, which are slave nodes relative to the predetermined node.
In addition, to guarantee that the slave nodes are properly updated, the master node must receive responses from each of the slave nodes. In this scenario, a round trip scheme is employed between each slave node and the master node, in which a message is sent and then an acknowledgement is awaited. A round trip scheme is also employed if a slave node sends a synchronization request message to the master node, and the master node responds by sending a synchronization message. The inaccuracy of time provided to a slave node in these scenarios is directly related to the total elapsed time for the round trip sequence of messages. Thus, the precision with which clock synchronization can be achieved is limited by the time required for round trip synchronization.
ROUND TRIP CLOCK SYNCHRONIZATION
A more detailed description of round trip synchronization will now be given. A particular type of round trip synchronization, called Probabilistic Clock Synchronization (hereinafter PCS) has been used for synchronizing internal times of nodes with reference time from a designated reference node or from an external source. The technique is described in Cristian, "Probabilistic Clock Synchronization", IBM Technical Disclosure Bulletin, Vol. 31, No. 2 (July 1988), p. 91.
The basic round trip synchronization sequence works as follows: A slave node sends a synchronization request at a time t, according to its clock. A master responds with a message giving a time T, according to the master's time clock. The slave receives the response at a time t', according to its clock. It is thus established that the master's time T falls somewhere within the time interval between the slave's times t and t'. The slave then updates its internal time in accordance with a difference between the reference time T and an internal time somewhere between t and t'.
(Note that the above paragraph presupposes that the slave node is to synchronize its clock with the reference time falling between two of its local times. The reverse can also be done; that is, two reference times can be obtained, a local time falling between the two reference times, and the local time can be synchronized with a time falling between the two reference times.)
While the reference time T can be synchronized with any local time t* within the interval from t to t', the precision is given by the larger of the two differences t*-t and t'-t*. To minimize this interval, and therefore make the precision as good as possible, it is preferable to synchronize T with the midpoint of the interval between t and t'. That is, T is synchronized with the local time t* =(t'-t)/2. Thus, the precision of the slave node's synchronization is accurate to within (t'-t)/2.
In particular, Cristian's PCS technique includes checking the precision which is achievable from a given set of times identified as above. If the achievable precision is not considered good enough, the round trip message exchange sequence is repeated to provide another set of time intervals with which the above method can be used to synchronize the slave node. If the process is repeated until a suitably short interval is obtained, the precision of synchronization is improved.
Thus, the probabilistic clock synchronization technique described in Cristian advantageously provides both synchronization and a quantitative estimation of the precision of synchronization, i.e., an upper bound of synchronization error. However, because this technique uses a round trip protocol for providing synchronization intervals to slave nodes on an individual basis, it has the drawback that the bidirectional message protocol requires a substantial amount of processing overhead. This is particularly true for the reference time source, which must go through the synchronization protocol for each slave node for which the master is responsible. As a consequence, the time interval t'-t is of a size commensurate with the processing time. It would be desirable to perform clock synchronization using a smaller interval, and thereby improve the accuracy of synchronization.
A further complication is added when it is taken into account that each of the three times t, T, and t' has a precision value associated with it. That is, instead of having one discrete point in time, according to a first time scale, falling somewhere between two discrete points in time, according to a second time scale, each of the three points in time has a "halo," or plus-or-minus precision range, surrounding it. A clock synchronization scheme should take these precision ranges into account, in determining the accuracy of synchronization.
With this additional consideration of plus-or-minis precision ranges in mind, the Background section of this patent application will conclude with a discussion of the intervals in a PCS sequence, in terms of a notating convention describing both times and precision intervals. This same notation will be used further in the discussion of the invention which follows.
Round trip synchronization, in essence, follows the following steps, which will be illustrated with reference to the timing diagram of FIG. 1. For clarity, FIG. 1 shows plus-or-minus precision ranges which are small, relative to the intervals between the time points, and which therefore do not intersect. In some realistic situations, however, there may be substantial overlap between the intervals.
Process A obtains a time stamp, from its local clock, of a time T, plus or minus a precision estimate P (2). Next, Process A sends a message (4) to Process B, which receives the message some time later. Process B then obtains a time stamp, from its local clock, of a time U, plus or minus a precision estimate Q (6). Process B then sends a response (8) back to Process A, which receives the response at a still later time. Upon receipt, Process A obtains, from its local clock, a time stamp of a time V plus or minus a precision estimate R (10).
A PCS scheme selects a time, in terms of Process A's time scale, which is to be treated as equal to the Process B time Q, for synchronization. As discussed above, the midpoint (V+T)/2 of the interval between the two Process A times T and V produces the best precision (12). Therefore, when performing PCS synchronization, the Process B time U (6) and the midpoint (V+T)/2 of the interval between the Process A times T and V are synchronized with each other.
This synchronization involves changing Process A's time by the difference between U and (V+T)/2 (14). Process A's current time is V, so the synchronization process adds (U-(V+T)/2) to V, to produce the resynchronized time U+(V-T)/2 (16).
Next, the precision values Q and R and the interval V-T are used to compute a precision range for the new synchronized value. According to Process B, the precision at time U was plus or minus Q. Since the new precision can be as great as (V-T)/2, that is, half of the interval between T and V, and since there is already an existing precision of Q, the new precision s the sum of these two terms, or Q+(V-T)/2.
In summary, given the above sequence of messages, a single round trip according to the PCS scheme produces, for Process A, a new time U+(V-T)/2 plus or minus a precision of Q+(V-T)/2. The endpoints of this new interval, as of the present time, are U-Q and U+Q+V-T.
This new time, including the time value itself and the precision interval, is adopted as Process A's new time if (i) the precision Q+(V-T)/2 is less than Process A's current precision R, and (ii) the precision is less than a user supplied parameter, a requested precision. (The smaller the precision value, the better the precision. ) If one of these two conditions is not met, the preexisting Process A time and precision interval of V plus or minus R is kept. Another PCS round trip may then be attempted, to try to obtain a precision good enough to adopt. However, as discussed above, it would be desirable further to improve precision of synchronization.
SUMMARY OF THE INVENTION
It therefore is an object of the invention to provide a clock synchronization method which has the advantages of probabilistic clock synchronization, and which also provides enhanced synchronization accuracy.
To achieve this and other objectives, there is provided in accordance with the invention a method for synchronizing the time representations of nodes in a multiprocessing network. The network typically includes first and second nodes coupled to a communication network. Each of the first and second nodes maintains a respective time representation to within a respective precision.
The method includes the initial step of obtaining one time value for each of two time scales maintained by two nodes which are to be synchronized with each other. This is preferably done using a suitable method, such as a Probabilistic Clock Synchronization or other round trip method, by exchanging a predetermined sequence of messages between the first and second nodes. As described above, the midpoint between the two Process A times and the Process B time are used as the time values for the two time scales.
More specifically, the time values are to be obtained in terms of an instantaneous time value and a precision value, such as a plus-or-minus accuracy range or interval. As will be discussed in detail below, the intervals of the two times will have one of a predetermined set of intersection patterns.
The method further includes the step of computing a new estimated correct time, and a new precision range about the estimated correct time. The estimation is made in terms of the time values and precision ranges of the intervals of the exchanged messages. In accordance with the invention, this step employs a technique of noting the intersection, if any, between the time-and-precision-value intervals for the two time scales. The intersection, if any, between the two intervals is treated as a new interval for the newly resynchronized time.
To produce an instantaneous time value and a plus-or-minus precision interval surrounding the instantaneous time value, the intersection interval is bisected to determine its midpoint. The midpoint thus produced is the new time value. Also, one half of the length of the intersection interval is used as the new precision. As a result, the plus-or-minus precision range of the new synchronized time value is identical to the intersection interval.
It will be understood that two intervals can intersect in several different ways. Referring back to the final portion of the Background, the endpoints of the possible intersection intervals are given in terns of the times T, U, and V, and the precisions P, Q, and R. As a consequence, the calculation of the new time and precision is made from one of a predetermined number of respective formulas. The formulas correspond with the intersection patterns of the possible intersection intervals, and the particular formula used is the one which corresponds with the intersection pattern of the intervals in the particular case.
While the invention is primarily disclosed as a method, it will be understood by a person of ordinary skill in the art that an apparatus (FIG. 12), such as a conventional data processor 200, including a CPU 202, memory 204, I/O 206, program 208, a connecting bus 210, and other appropriate components, could be programmed or otherwise designed to facilitate the practice of the method of the invention. Such a processor would include appropriate program means for executing the method of the invention. Also, an article of manufacture, such as a pre-recorded disk 212 or other similar computer program product, for use with a data processing system, could include a storage medium and program means recorded thereon for directing the data processing system to facilitate the practice of the method of the invention. It will be understood that such apparatus and articles of manufacture also fall within the spirit and scope of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a timing diagram showing a round trip synchronization sequence according to the conventional Probabilistic Clock Synchronization method.
FIG. 2 is a timing diagram showing the conventional use of the intersection of intervals to establish a correct time for synchronization, as taught in Distributed Computing Environment, Time Service Specification, Version T1.1.0 (Jun. 11, 1991), Section 2.3, pp. 8-11.
FIGS. 3, 4, 5, and 6 are timing diagrams showing four possible intersection patterns for two intervals, the intersection patterns being used, in accordance with the invention, for time synchronization.
FIG. 7 is a flowchart showing a preferred implementation of the method of the invention.
FIGS. 8, 9, and 10 are flowcharts showing a more detailed description of preferred embodiments of respective steps of FIG. 7.
FIG. 11 is a block diagram showing a system for practicing the method of the invention.
FIG. 12 is a schematic diagram of a processor (i.e., node) according to the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Initially, a discussion of the use of the intersection of intervals for obtaining a correct time for synchronization will be discussed, in connection with the prior art teaching in Distributed Computing Environment, Time Service Specification, Version T1.1.0 (Jun. 11, 1991), Section 2.3, pp. 8-11. FIG. 2 of the present patent application is reproduced from FIG. 2.2 of this document.
A plurality of times are received from one or more Time Providers, such as external reference time sources or time services. Each of the received times includes a precision range. Accordingly, the times are shown in FIG. 2 as intervals in time lines.
The intervals from the different Time Providers need not be identical to each other, and are likely to be somewhat different from each other, due to factors such as clock drift. Moreover, it is possible that one or more of the Time Providers might be faulty, and therefore that its time interval might be far away from the correct time.
Assuming that all of the intervals were provided by operational Time Providers, it will likely be the case that all of the intervals have a finite intersection, and it may be assumed that the correct time falls within that intersection of the intervals. An example is shown in FIG. 2, in which a correct Universal Coordinated Time (UCT) falls within the intersection of three intervals S 1 , S 2 , and S 3 .
An additional discussion of intervals in connection with clock synchronization from multiple time sources is given in Marzullo, "Maintaining the Time in a Distributed System: An Example of a Loosely-Coupled Distributed Service", Ann Arbor, Mich.: University Microfilms International (1984), a Stanford University Ph.D. dissertation.
Marzullo recognizes that, in a distributed system, a clock time is given in terms of a clock value and an error bound, thus given as a time interval. See Section 2.2 and FIG. 2.1 in Marzullo. Additionally, Marzullo teaches a scheme for using intersection of intervals in connection with clock synchronization in distributed systems, in sections 3.1 and 3.2. Assuming that there are several clock sources, each having an interval made up of a time and a precision range, Marzullo teaches finding an intersection of the intervals for all of the time sources (if there is such an intersection), and using that intersection interval for synchronization. The intersection interval is made up of the greatest lower bound and the least upper bound. Typically, for fairly accurate clock sources, this intersection interval will be finite in size, but smaller than any one of the intervals for any of the individual clock sources. The intersection interval may then be used to establish a precision range for the newly synchronized time.
THE INVENTION
The present invention utilizes the basic theory of interval intersections as applied to clock synchronization in a context different from that which Marzullo contemplated. In Marzullo's context, several different remote clock sources send times, including precision ranges given as intervals, to a local node wishing to synchronize its internal clock. The intervals have some intersection, which is then used for the synchronization.
By contrast, the present invention is applicable to situations where a local node seeks to synchronize its local clock, and only a single remote clock are available. As a consequence, there will not be multiple external times to intersect, as was the case with Marzullo's scheme. Through a suitable process, such as a round trip message exchange sequence, the local node identifies a local time and a remote time, each having a precision range given in terms of a time interval, which are to be used for the synchronization. Then, the intersection of the two intervals is used to establish the new, synchronized time, including its precision range.
Let us now return to the PCS sequence described in the Background. In accordance with the PCS scheme, as modified in accordance with the invention, the midpoint (T+V)/2 between Process A's two time stamps T and V is to be synchronized with the time stamp U from Process B, and a precision range is to be calculated for the newly synchronized time, based on the times T, U, and V, and their respective precisions P, Q, and R.
For the discussion which follows, it will be assumed that Process A (the process whose two times surround the Process B time), is the local node, and is the node whose time value will be adjusted. However, it will be understood that the local node whose time is to be adjusted could also be the Process B node, whose time falls between the two received Process A time stamps. The method of the invention works either way.
If there were no precisions to worry about, but merely instantaneous time values, then Process A would adjust its clock to compensate for the difference between U and (T+V)/2. However, because each time stamp has a precision interval associated with it, the synchronization problem is not the difference between two instantaneous points according to two time scales, but rather the synchronization of two time intervals according to two time scales.
Initially the midpoint between T and V is taken as the Process A instantaneous time which is to be used for synchronization. Next, the precision interval around that point must be determined. Assuming that the precision interval for Process A increases with time, due to factors such as clock drift, it will be understood that at time (T+V)/2, the precision was somewhere between P and R.
However, in accordance with the invention, it is taken into account that the time is no longer (T+V)/2 or U, but the later time V (or actually a little later than V, allowing for processing time). Therefore, the additional clock drift between the two Process A times (T+V)/2 and V has caused the precision error to grow from P to R (or actually a little greater than R, allowing for the additional clock drift which accrues during the processing time). Therefore, for the purpose of comparing intervals for synchronization, the precision error about the midpoint (T+V)/2 is taken as R. That is, one of the two intervals to be intersected is the Process A interval, (T+V)/2±R.
The Process B interval provided with the response message was U±Q. This could be used as the interval. However, in accordance with the PCS message exchange scheme, the Process B time U could fall anywhere between T and V. As a consequence, the precision of the Process B interval is expanded to include the maximum possible additional error, (V-T)/2. Thus, instead of the Process B interval being U±Q as per the response message, the Process B interval will now be U±(Q+(V-T)/2).
From the above discussion, expressions have been defined which identify midpoints and endpoints for the two intervals, identified through use of the PCS message exchange scheme, which are to be intersected, in accordance with the invention, to provide a synchronization time and precision range.
For the two intervals, there are four possible intersection patterns. These four patterns are shown in FIGS. 3, 4, 5, and 6. These four FIGURES are timing diagrams, in which the two intervals are shown on time lines labeled for the respective processes whose times are depicted on the time lines. The endpoints of the time intervals are labeled in accordance with the derived expressions given above. For each pair of intervals, a third interval is given, showing the intersection of the two intervals.
Note that a fifth possibility is that the intervals do not intersect at all. If this were the case, then the PCS round trip message exchange will have failed to produce intervals upon which synchronization can take place. Another attempt to run the PCS message exchange may then be made, to try again to get suitable intervals. Alternatively, this failure of the intervals to intersect at all may be taken as a system failure or a catastrophic failure of clock synchronization, and an alarm or appropriate diagnostic procedure may then be invoked.
Let us now consider the four possible intersection intervals given, to see how they are used, in accordance with the invention, to obtain better precision in synchronization. In the case of FIGS. 3 and 4, one interval is contained entirely within the other, so the intersection is equal to the shorter of the two intervals. These two cases correspond with conventional PCS.
Let us consider first FIG. 3. Process A, whose time is to be adjusted for synchronization, has a relatively narrow precision range of ((T+V)/2)±R. The Process B time has a larger precision range, as shown, so Process A's precision would not improve if Process A performed a synchronization based on this exchange of messages. Accordingly, Process A does not perform a synchronization based on this message exchange. Instead, Process A initiates another message exchange, takes other appropriate action or just maintains its current time. The scenario in FIG. 3 is equivalent to the conventional PCS scenario where the message exchange does not provide for synchronization which improves, in precision, on the current time.
Next, let us consider FIG. 4. Here, the Process B time interval is smaller than the Process A time interval. Process A would improve its precision by synchronizing with the Process B time, and therefore does so. This is equivalent to the conventional PCS scenario where the message exchange does provide for synchronization which would improve Process A's precision.
The two cases shown in FIGS. 5 and 6 are those for which, in accordance with the invention, the improved precision is achieved. In these two cases, the intersection between the two intervals is less than either of the two intervals in their respective entireties. However, the assumption is made that the correct time falls within the intersection of the two intervals. Thus, the precision achieved is related, not to the full size of either the Process A or the Process B interval, but, rather, to the smaller size of the intersection of the two intervals. Because of this assumption, the precision range of the intersection interval is smaller, and correspondingly better, than that achieved if either of the two intervals, in its entirety, were used for synchronization.
Let us consider first FIG. 5, which shows the result of a PCS message exchange in which the latter part of the Process A interval overlaps the initial part of the Process B interval. In accordance with the invention, the assumption is made that intersection of the two intervals encloses the correct time, so this interval may be used as the precision range for the newly synchronized time. In the scenario of FIG. 5, that interval runs from U-(Q+(V-T)/2) to (T+V)/2+R. Since this interval is shorter than either of the Process A and B intervals, use of this interval as the precision range for the resynchronization produces advantageously greater precision.
There remains the task of determining where, within this interval, lies the time which will be taken as the instantaneous time. As discussed above, a precision is best when the precision range above and below the time are equal; that is, when the instantaneous time is the midpoint of the precision interval. Accordingly, the instantaneous time for the intersection interval of FIG. 5 may be computed from the sum of the two endpoints, divided by 2, or (T+U-Q+R)/2. Similarly, the precision range is given by taking the difference of the endpoints and dividing by 2, or (V-U+R+Q)/2.
Therefore, the synchronization is to be made by adjusting the instantaneous time of Process A to compensate for the difference between (T+V)/2 and the midpoint of the intersection interval, (T+U-Q+R)/2. Since the present time, according to Process A's time scale, is V±R, the midpoint is determined by adding, to the current time V, the compensation factor given by the difference (T+U-Q+R)/2-(T+V)/2. Thus, the new instantaneous time is (V+U-Q+R)/2. The plus-or-minus precision range is as given above
Finally, let us consider FIG. 6, which shows the result of a PCS message exchange in which the initial part of the Process A interval overlaps the latter part of the Process B interval. In accordance with the invention, the assumption is again made that the falls within the intersection of the two intervals. In the scenario of FIG. 6, that interval runs from (T+V)/2-R to U+(Q+(V-T)/2). Since this interval is shorter than either of the Process A and B intervals, use of this interval as the precision range for the resynchronization also produces advantageously greater accuracy.
There remains the task of determining where, within this interval, lies the time which will be taken as the instantaneous time. Again, the instantaneous time is preferably taken as the midpoint of the precision interval. Accordingly, the instantaneous time for the intersection interval of FIG. 6 may be computed from the sum of the two endpoints, divided by 2, or (V-R+U+Q)/2. Similarly, the precision range is given by taking the difference of the endpoints and dividing by 2, or (U-T+Q+R)/2.
Therefore, the synchronization is to be made by adjusting the instantaneous time of Process A to compensate for the difference between (T+V)/2 and the indpoint of the intersection interval, (V-R+U+Q)/2. Since the present time, according to Process A's time scale, is V±R, the midpoint is determined by adding, to the current time V, the compensation factor given by the difference (T+V)/2-(V-R+U+Q)/2. Thus, the new instantaneous time is V +(U+Q-R-T)/2. The plus-or-minus precision range is as given above
The above discussion provides a detailed mathematical analysis of the method of the invention, as preferably practiced using Process A and Process B synchronization intervals provided by means of a PCS message exchange, and by following the general assumption that the best overall precision for a time expressed in terms of an instantaneous time and a precision range having the instantaneous time as its midpoint. It will be understood, however, that other techniques can be used to identify Process A and Process B intervals which are to be used for synchronization. Also, the instantaneous time value need not be the midpoint of a precision interval, although, as discussed above, the precision is best when this is so. However, the analysis of the possible intersections of the two intervals to identify endpoints of the intersection intervals, and the identification of an instantaneous time point will proceed substantially as above, except for suitable alterations that satisfy the particular techniques used.
The present discussion will conclude with a description of the method of the invention, as shown in the accompanying flowcharts. FIG. 7 is a flowchart showing the overall method of the invention. Initially, in step 20, two times, given in terms of an instantaneous time value and a precision range around that value, are obtained. As discussed above, this is preferably done through the use of a PCS message exchange sequence.
Such an exchange is briefly summarized in FIG. 8. As discussed above in connection with FIG. 1, Process A sends a message at its time T±P. Process B later receives the message at a later time U±Q, and sends a response with a time stamp. Process A later receives the response, at its time V±R. Thus, it is established that the time U±Q falls between the times T±P and V±R. Step 22 in FIG. 8 shows this step.
Again, it should be borne in mind that a suitable message exchange could alternatively identify two Process B times, between which a Process A time falls. The remainder of the method of the invention is then suitably modified.
Referring again to FIG. 8, the instantaneous time according to Process A which is to be synchronized with the Process B time stamp (or vice versa, as above) is identified, preferably as the midpoint between the two times (step 24). Finally, a precision range interval about that instantaneous time is determined (step 26).
Returning now to FIG. 7, step 28 tests which of several possible intersection patterns result from the intersection of the Process B interval and the interval produced for Process A as per FIG. 8. If the intervals do not intersect at all (step 30 ), then the synchronization cannot proceed. A retry may be executed by repeating step 20, or a suitable error condition may be flagged, as appropriate (step 32).
If one interval falls completely inside the other (step 34), as illustrated in FIGS. 3 and 4, then the intersection of the intervals in accordance with the invention does not produce an advantageous improvement in precision. Rather, the precision achieved is the same as that according to conventional clock synchronization. Accordingly, Process A proceeds as per a conventional synchronization technique, either synchronizing, if a desired precision improvement would result, or, if it would not, then retrying or not proceeding further (step 36).
A more detailed description of step 36 is given in the flowchart of FIG. 9. The determination of which of the two cases (FIGS. 3 and 4) has occurred is given schematically as step 38. If the local interval (T+V)/2±R is smaller than, and contained entirely within, the remote interval U±(Q+(V-T)/2), so no improvement would result from the synchronization (step 40), then the local node simply maintains its time as V±R. Depending on the particular circumstances, the local node either retries the PCS message exchange to try to obtain a more favorable pair of intervals, or simple keeps its current time. This is shown in step 42.
On the other hand, if step 38 determines that the remote interval U±(Q+(V-T)/2) is smaller than, and contained entirely within, the local interval (T+V)/2±R, then the local node can improve its precision by performing the synchronization. Step 44 then tests whether the improvement in precision is great enough to satisfy a threshold condition. Any suitable threshold condition may optionally be used here. If not, the processing proceeds to step 42, as described above.
If, on the other hand, the precision improvement which would be realized by synchronization on these intervals is great enough to satisfy the threshold condition, then synchronization actually proceeds (step 46). As described in the Background, the local node synchronizes its time from V +R to (U+(V+T)/2)±(Q+(V-T)/2).
Let us now consider the remaining two cases provided for in FIG. 7. If the two intervals both partially overlap each other (step 48 ), then synchronization is performed, and a precision range is determined based on the intersection between the two intervals (step 50). This may be done using the formulas given above, or by suitable alternative formulas which would be derived, in the same manner as given above, based on the particular circumstances in the alternative situation.
FIG. 10 is a more detailed flowchart showing the operation of step 50 of FIG. 7. Initially, a determination is made as to how the two intervals overlap. For convenience, this is shown as a test step 52. The two possible intersection patterns are as given in FIGS. 5 and 6, so for convenience, steps are shown which refer to FIGS. 5 and 6, respectively.
If the intervals intersect as per FIG. 5 (step 54), then the Process A (local) time is synchronized as per the discussion given in connection with FIG. 5 (step 56). If they intersect as per FIG. 6 (step 58), then the intervals intersect as per the discussion given in connection with FIG. 6 (step 60).
Therefore, in either event, Process A's current time V will have been synchronized in accordance with a difference between Process A's previous time (T+V)/2 and the midpoint of the intersection interval, given by the appropriate formula. The new precision for the Process A time is given by the size of the intersection interval. Accordingly, an improved precision is obtained where the intersection is smaller than either of the Process A or Process B intervals, taken by themselves.
Those skilled in the art will recognize that the foregoing description has been presented for the purposes of illustration and description only. It is 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.
Therefore, the embodiments set forth herein are presented in order to best explain the principles of the present invention and its practical applications to thereby enable others skilled in the art to best utilize the present invention in various embodiments, modifications, and equivalents as are suited to the particular use contemplated. | A probabilistic dock synchronization scheme for synchronization of time docks between nodes on a communication network is disclosed, in which a round trip exchange of messages is used to establish that one time according to a first time scale falls between two times according to a second time scale. A time related to the two second time scale times, preferably midway between the two times, is used for synchronizing with the time according to the first time scale. Each time is given in terms of a time value and a plus-or-minus precision range, thereby defining an interval. Enhanced precision is achieved by computing a new precision range for the synchronized time based on an intersection between the intervals of the related time and the time according to the first time scale. | 7 |
REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of my prior copending application Ser. No. 174,428, filed Mar. 28, 1988, now abandoned all disclosure of which is incorporated herein by reference.
TECHNICAL FIELD
This invention relates to means for controlled propulsion of boats, and in this context to new, useful and highly efficacious variable pitch propeller blade constructions, and drive and adjusting mechanisms for such propellers.
BACKGROUND
Various mechanisms for adjusting the pitch of rotatable blades (propellers, fan blades, etc.) have been described heretofore. See for example U.S. Pat. Nos. 494,014; 573,977; 810,032; 1,332,475; 1,407,080; 1,491,589; 1,779,050; 1,806,325; 1,869,280; 2,084,655; 2,354,465; 2,394,011; 2,470,517; 2,478,244; 2,711,796; 2,870,848; 2,885,013; 2,939,334; 3,122,207; 3,138,136; 3,518,022; 3,795,463; Canadian 463,179; French 1,177,427; Italy 547,875; and Japan 57-46091.
Although differently shaped blades have been described for use in driving a boat or other vessel through water, the most commonly used type involves a blade having a helically shaped (twisted) configuration.
Heretofore, when flat bottom boats or other boats of shallow draft entered marshy areas choked with vegetation or thick muddy areas covered with but a few inches of water--situations which can readily be encountered in swamps such as exit in southern Louisiana and in other swampy regions--it was very likely that the boats would become mired and bogged down so that they could not move in any direction. Contributing to the problem was the fact that the driving mechanisms for small boats available on the open market rotate in only one direction and are equipped with helically twisted propellers that can readily become entangled in thick vegetation.
SUMMARY OF THE INVENTION
An object of this invention is to provide new, useful and highly efficacious variable pitch propeller blade constructions which work well in propelling boats, especially flat bottom boats, through very shallow water, or mud, or swampy or marshy areas, even those choked with vegetation.
A further object is to provide a variable pitch propeller blade configuration which when used with conventionally sized and rated outboard motors or engines (e.g., 10-25 hp) provides the power needed to drive flat bottom boats and other boats of shallow draft through wet muds and marshes, even when the area is choked with swamp grasses and other similar vegetation commonly encountered in swampy and marshy areas.
Still another object is provide a variable pitch propeller blade configuration which can be used to propel the boat--including flat bottom boats--through wet muds and marshes under conditions of the type just described, yet which can propel the very same boat at a relatively high rate of speed through open water, again without need for more powerful motors or engines than are customarily used as outboard motors for boats.
Yet another object is to provide variable pitch propeller blades that can be adjusted by the operator through a continuum of positions ranging from fast forward to fast reverse so that the boat can be operated at a full range and variety of speeds, can be stopped rapidly, and can be maneuvered with precision.
A further object is to provide a propeller blade configuration and mechanism enabling the operator to run the boat at any particular speed within a continuous range of speeds, and, without changing engine speed, swiftly stop the boat and even reverse its direction of movement if the need or desire to do so arises.
Another object is to provide a mechanism that will enable the operator to run the boat at very slow or fast speeds with a minimum of noise.
Still another object is to provide a propeller blades and propeller blades assemblies that can be serviced and repaired easily and quickly.
These and other objects, features and embodiments of this invention will become further apparent as the discussion proceeds.
In accordance with one embodiment of this invention a variable pitch propeller blade is provided in which the blade is of generally planar configuration, i.e., there is no twist or helical configuration in the blade. One portion of the blade (the leading edge portion) is relatively thin and another portion (a median and/or a trailing edge portion) is somewhat thicker to provide the necessary strength and rigidity to the blade. The blade is configured such that the thin leading edge portion of the blade has a swept back or retracted curvature along a substantial portion of its length when proceeding in the direction of inner end to outer end. While such blades may have generally convex or concave outer surfaces (faces), it is preferable that they have substantially flat outer surfaces. In other words, the front and rear faces of such blades may be convex or slightly concave between the leading and trailing edge portions, but preferably, are substantially flat between the leading and trailing edge portions. Affixed to the inner ends of each such blade is a means (preferably a cylindrical stub or the like) for rotating the blade in a continuous series of planes whereby the position of the blade can be adjusted to and from a fast forward position through neutral and to and from a fast reverse position, and can be set at any and all stages therebetween so that the boat may be operated in either direction (forward or reverse) without adjusting the speed of the engine and can be manuevered with quick response and precision. Indeed, these blades enable the boat to be rocked back and forth while the boat is being turned in a very small space, and this in turn enables the boat to be disengaged from thick vegetation rather than becoming mired and bogged down as is the case with boats equipped with conventional propellers and propulsion systems. When the blade is in a forward propelling position the leading or sharp edge of the blades projects forwardly of the plane which is perpendicular (transverse) to the axis of the propeller shaft. When the blade is in a rearward propelling position the leading or sharp edge of the blade projects rearwardly of the plane perpendicular (transverse) to the axis of the propeller shaft). And when the blade is in its neutral position (propelling neither forwardly or rearwardly) the plane of the blade falls substantially along the plane which is perpendicular (transverse) to the axis of the propeller shaft. The angular displacement between the plane of the blade and the perpendicular plane governs the speed at which the boat will be propelled: the greater the angle, the higher the speed. For most types of general service, provision will be made to allow the angular displacement between the plane of the blade and the perpendicular plane to be adjusted to as much as 45° in both forward and reverse. However the limits of adjustment for these ranges may be varied as deemed necessary or desirable. Normally, and preferably, these stubs in turn will be received within a hub containing a suitable mechanism for applying a rotational torque to the stubs to rotate the stubs about their respective axes and thereby rotate the planar blades and adjust their pitch while at the same time causing the blades to be rotated about the axis of the propeller shaft so that the leading edge is always the forwardmost portion of the blade cutting into the water (whether operating in forward, reverse or neutral). In a preferred embodiment two such blades are disposed on and extend from opposite sides of a rotatable hub and are operatively connected to means for translating linear motion into axial rotational torque upon the blade stubs for adjusting the pitch of the blades as desired by the operator.
Flat planar blades of the type described in the immediately preceding paragraph generate the greatest amount of power both in the forward and rearward directions. Thus such essentially flat planar blades with a relatively sharp leading edge portion and a relatively thicker median and/or trailing edge portion are preferred for use in mud boats and other similar flat bottom boats to be used in swamps and marshes, especially where the water is as shallow as one to two inches or less, and where thick mud and/or heavy vegetation may be encountered. For convenience these blades will often be referred to hereinafter as the "flat planar blades".
In another embodiment of the this invention a variable pitch propeller blades of the type described above is provided differing in that the plane of the blade is curved or bent along its length. The curvature commences at a locus at least about one-half (preferably between about one-half and about three-fourths, most preferably about two-thirds) the distance from the innermost portion of the blade to the outermost portion of the blade. The direction of the bend is always toward the front of the boat. Thus there are basically two such curved blade configurations, depending upon the direction in which the hub and blades are to be rotated. If the propeller drive train is arranged so that the hub and blades rotate clockwise (when viewed from behind the propeller and looking in the direction of forward boat travel) the plane of the blade curves toward the front of the boat and when the blades are in the 12 o'clock position, the relatively sharp leading edge is toward the right hand side. However, if the propeller drive train is arranged so that the hub and blades rotate counter-clockwise (when viewed from behind the propeller and looking in the direction of forward boat travel) the plane of the blade again curves toward the front of the boat, but when the blades are in the 12 o'clock position, the relatively sharp leading edge is toward the left hand side. It is to be noted that although the outer end portion of the blade is bent in the appropriate direction (i.e., toward the front of the boat), the blade is not helically twisted. Rather, the blade when viewed edgewise is substantially flat, but bent along an outer portion of its length. For convenience these blades will often be referred to hereinafter as the "bent planar blades", and collectively the "flat planar blades" and the "bent planar blades" will often be referred to collectively hereinafter as the "planar blades". It will thus be understood that in all cases the planar blades have a relatively sharp, outwardly receding or retracted (swept back) leading edge and a somewhat thicker median zone or trailing edge (which may itself be rounded off, squared off or even tapered down in thickness for a short distance), and most preferably their front and rear faces are substantially flat (as distinguished from being radially twisted).
The bent planar blades generally do not generate quite as much power in the forward and rearward directions as the flat planar blades, yet they still can provide enough power to move even flat bottom boats through reasonably thick muds and marshes. An advantage of the bent planar blades is that they make possible the attainment of higher boat speeds than the flat planar blades. Accordingly the bent planar blades represent an excellent compromise between speed and power, and are thus well suited for use in mud boats and other similar flat bottom boats to be used both in open water and in swamps and marshes, even where water as shallow as one to two inches and where mud and/or vegetation may be encountered.
The receding or swept back (retracted) curved leading edge is one of very important features enabling the blades, especially the flat planar blades, to cut through thick muds covered with but a few inches of water or through marshy areas choked with vegetation such as swamp grasses, water lilies, and the like. This and the fact that the planar blades of this invention are adapted to be rotated on the axis of their stubs enables the blades to maneuver the boats back and forth with great precision in extricating the boat from thickly vegetated areas, to cut through snags and snares that would tend to foul conventional propellers, and to shed vegetation that would choke and foul conventional propellers. Helically twisted and even planar blades that are paddle shaped with more or less convex leading and trailing edges are incapable of performing effectively under such conditions. Likewise planar blades with more or less straight leading edges cannot operate effectively under these conditions.
It will be appreciated that the receding or swept back (retracted) curved leading edge need not be (but preferably is) composed of a smooth uninterrupted curve. In lieu thereof the curvature of the swept back leading edge may include in whole or in part a series of short straight adjacent segments arranged tangentially on an imaginary smooth curved leading edge with the segments successively intersecting each other so that the overall effect is one of approximating a smooth retracted curved leading edge by means of such short adjacent straight segments. Similarly, the smooth retracted curved leading edge may be interrupted along its length by one or more spaced-apart short segments of this type whereby once again a smooth retracted curved leading edge is closely approximated. Further, the swept back leading edge may be smooth or serrated.
In accordance with a particularly preferred embodiment of this invention at least the innermost end of the leading edge of each planar blade is in very close proximity to, and most preferably projects from, an arcuate recess in the exterior of the hub, and most preferably such leading edge extends substantially tangentially from the hub for a short distance outwardly from the hub when the blade is in the neutral position--i.e., when the blade has been rotated on its axis such that the leading edge of the blade falls in a plane perpendicular to the axis of the hub and propeller shaft. The arcuate recess in the hub serves a twofold purpose. First, it enables the inner end of the leading edge to be in direct or substantially direct contact with the hub irrespective of the extent to which the blade is rotated radially about its axis. This prevents or at least greatly reduces the chances of vegetation or other debris becoming wedged or entangled between the blade and hub. Secondly, the lateral ends of the recess can serve as stops to prevent over-rotation of the blade in either direction when adjustments in blade pitch are being made. Such blades of course also possess the swept back curved leading edge described above. For convenience such blades are sometimes referred to hereinafter as the "grooved tangential swept back planar blades". In this connection, the term "grooved" is used in the sense that the inner end portion of the leading edge portion of the blade is positioned or is to be positioned such that it fits into an arcuate groove in the exterior of the hub--it does not mean that the blade itself is grooved. Experiments conducted under actual service conditions have shown that grooved tangential swept back flat planar blades of the type referred to in this paragraph can give the very best results as they most effectively (a) cut through mud and vegetation, (b) shed the cuttings, (c) avoid fouling at all locations on the blade and hub, (d) drive the boat at high speeds when conditions warrant, and (e) maneuver the boat under conditions where conventionally propelled boats would become bogged down and hopelessly mired in the swamp. Such blades are virtually foul-proof.
The blades of this invention can be utilized with any mechanism or system which enables the stubs on the blades to be axially rotated such that the pitch of the blades can be adjusted by the operator throughout the desired range of positions, and yet held fast in the selected position. However it is definitely preferred to utilize a variable pitch propeller drive and adjusting mechanism of the type described hereinafter. Thus in accordance with a further embodiment of this invention a variable pitch propeller drive and adjusting mechanism is provided which comprises: (a) a hollow drive shaft terminating in a hub; (b) a pitch adjusting shaft rotatable with and longitudinally moveable in the drive shaft; (c) a pair of planar blades (of the types described hereinabove) each with a cylindrical stub on its inner end portion, the stubs extending into the hub through a pair of hereinafter-referred-to bearings; (d) means within the hub translating longitudinal movement of the pitch adjusting shaft into opposed rotational movement of the stubs about an axis perpendicular to and extending through the axis of the drive shaft; and (e) a pair of bearings mounted in and affixed to the hub to accommodate such rotational movement of the respective stubs; the apparatus being further characterized in that (f) the blade stubs within the hub are shaped to axially abut and rotatably engage each other; and (g) the pitch adjusting shaft is slidably fitted within one or more bushings or bearings mounted in the drive shaft.
The longitudinal position of the pitch adjusting shaft within the hollow drive shaft can be adjusted by means of a control or shaft lever mechanism. A feature of this invention is that the pitch of the planar blades can thus be adjusted through a continuum of positions ranging from fast forward to fast reverse without need for stops or other restraining means imposed on the shift lever. Undesired changes in the pitch of the planar blades due to torsional forces generated in the water by the rotation therein of the blades around the axis of the drive shaft can be successfully nullified without need for such stops or like restraining means. Without desiring to be bound by theoretical considerations, it is believed that at least two combined effects are responsible for such nullification. First, undesired changes in the pitch of the rotating planar blades is believed to be resisted by the axial abutment and rotatable engagement between the ends of the stubs within the hub. This mechanical arrangement is believed to couple and pit the torsion derived forces from the blades against each other so that these forces tend to neutralize each other. Secondly, it is believed that the friction of the slidable fit of the pitch adjusting shaft within the bearing(s) or bushing(s) in the drive shaft and the centrifugal forces generated by the drive shaft bearing(s) and the pitch adjusting shaft rotating in unison tend to resist undesired change in the longitudinal position of the pitch adjusting shaft in the drive shaft, and as a consequence these factors also tend to prevent undesired changes in the pitch of the planar blades as the blades rotate in the water around the axis of the drive shaft. Whatever the mechanism may be, the plain fact is that prototype systems of this invention have been constructed in the manner disclosed and depicted herein and found to work well in actual service for suitably long periods of time.
Another feature of this invention is that by eliminating the need for stops or other restraining means on the control or shift lever mechanism to prevent unwanted pitch changes in the planar blades, the planar blades can under special or emergency conditions be rotated around the axes of their stubs. For example, if the planar blades strike a submerged log or other substantial underwater obstacle, the extra torsional force imposed on them by such impact can override the factors normally holding the blades in their selected pitch positions and thus move the blades to another position, usually neutral or close thereto, and thereby reduce the likelihood of damage to the planar blades or to other parts of the over-all mechanism.
It will be appreciated that while stops or other restraining means on the control or shift lever mechanism are not required, they may be used, if desired. In other words, it is not necessary to the practice of this invention that the system be constructed so that such stops or other restraining means are unnecessary. If such stops or other restraining means are found necessary or desirable in any given type of construction, they should of course be used. In one preferred system of this invention when adapted for use with mud boats propelled with engines or other prime movers providing up to about 25 horsepower (hp), the only such restraining means used is a pair of stops to prevent the pitch of the planar blades to exceed about 45 degrees from neutral in the forward or reverse position and more preferably up to about 25 degrees in the reverse position, so as to prevent the engine speed and load from becoming excessive and causing possible damage to the engine. Within these extremes the pitch of the planar blades may be adjusted as a continuum. This makes it possible to maximize engine and boat performance which may vary from case to case depending on the size and characteristics of the particular engine, boat and planar blades used. As noted above, when grooved tangential swept back planar blades are used, the lateral ends of the grooves can serve as the stops in lieu of other forms of restraining means to prevent overrotation of the blades. However, other forms of restraining means associated with the control lever may be employed along with the grooves in order to keep the blades in specific positions within the limits afforded by the lateral ends of the grooves.
Thus, in a particularly preferred system of this invention adapted for use with mud boats propelled with engines or other prime movers providing up to about 25-35 horsepower, the restraining means used is comprised at least in part of an arcuate groove or recess in the hub into which is fitted the inner end of the leading edge portion of a planar blade, the leading edge of which extends substantially tangentially from the hub for a short distance outwardly from the hub when the blade is in the neutral position, the lateral ends of the arcuate groove serving as stops to prevent overrotation of the blades on their axes.
Another embodiment of this invention provides a variable pitch propeller drive and adjusting mechanism which is readily serviced (e.g., packed with grease or other suitable lubricant) and, if need be, repaired. This mechanism comprises (a) a hollow drive shaft; (b) an open-ended hollow housing mounted on the end of the shaft and rotatable therewith; (c) a hub end cap detachably secured to the housing to cover the open end thereof and thereby form a hollow hub; (d) a pitch adjusting shaft rotatable with and longitudinally moveable in the drive shaft; (e) a pair of planar blades (of the types described hereinabove) each with a cylindrical stub on its inner end portion, the stubs extending into the hub through a pair of bearings (referred to hereinafter); (f) means within the hub translating longitudinal movement of the pitch adjusting shaft into opposed rotational movement of the stubs about an axis perpendicular to and extending through the axis of the drive shaft; and (g) a pair of bearings in the hub to accommodate such rotational movement of the respective stubs, each such bearing comprising a split bushing with one-half of the bushing mounted in and affixed to a recess in the housing at its open end and the other half of the bushing mounted in and affixed to an opposed recess in the hub end cap. It will be seen that this construction enables ready access to the means within the hub translating longitudinal movement of the pitch adjusting shaft into opposed rotational movement of the stubs, these being the elements that require most servicing (lubrication).
In each of the foregoing embodiments other features of this invention may be and preferably are employed. For example, the means translating longitudinal movement of the pitch adjusting shaft into opposed rotational movement of the stubs comprises (i) a yoke mounted on the end of the pitch adjusting shaft, the yoke including a pair of ears extending longitudinally beyond the end of the pitch adjusting shaft; (ii) a pair of lobes, each integral with a respective stub and extending radially along an axis perpendicular to the axis of the stub thereby forming a crank thereon, said lobes extending in generally opposite directions from each other; and (iii) a pair of links, each pivotally connected to a respective ear of the yoke and to the crank of the proximate stub. In mechanisms adapted for use in marshy areas containing marsh grasses or like vegetation, it is preferred that the drive shaft be rotatably supported within a casing, which casing has elongated substantially triangular fins mounted on and extending radially outwardly from opposite sides of its exterior such that the fins each provide in profile an inclined plane of progressively increasing height terminating in front of and in proximity to the transverse circular locus of rotation of the planar blades, the apex of such inclined plane extending radially to at least about the midpoint of the radial length of the blades. Another preferred feature for inclusion in such apparatus are (i) means for mounting a prime mover above the hollow drive shaft, and (ii) means for affixing an endless belt between the prime mover and the hollow drive shaft to enable the drive shaft to be rotated by the prime mover.
The above and still other embodiments and features of this invention should be readily apparent from the ensuing description, appended claims and accompanying drawings.
THE DRAWINGS
FIG. 1 is a side view of a preferred mechanism of this invention.
FIG. 2 is a top view, partly in phantom, of the mechanism of FIG. 1.
FIG. 3 is a section, partly in phantom, taken along line 3,3 of FIG. 1.
FIG. 4 is a side view of the hollow drive shaft with an open-ended hollow housing affixed thereto.
FIG. 5 is a front view of the inside of a hub end cap detachably securable to the hollow housing of FIG. 4.
FIG. 6 is an exploded side view in vertical section of the drive shaft and the hollow housing of FIG. 4 together with the hub end cap of FIG. 5.
FIG. 7 is a side view of a pitch adjusting shaft longitudinally slidable in bushings disposed in the drive shaft of FIGS. 4 and 6.
FIG. 8 is a top view of the pitch adjusting shaft of FIG. 7.
FIG. 9 is a back view of the outside of the hub end cap of FIG. 5.
FIG. 10 is a side view, partly in section, of a hub with means therein for translating longitudinal movement of the pitch adjusting shaft into rotational movement for adjusting the pitch of the blades.
FIG. 11 is a transverse exploded view of a pair of propeller blades each with a cylindrical stub and a lobe utilized, inter alia, for translating longitudinal movement of the pitch adjusting shaft into rotational movement for adjusting the pitch of the blades.
FIG. 12 is an end view taken along line 12,12 of FIG. 11 and showing, inter alia, a generally planar blade having convex outer transverse surface.
FIG. 13 is a transverse cross-section of a blade having a generally flat outer surface and one relatively thick edge and one relatively thin edge, the view taken along line 13,13 of FIG. 11.
FIG. 14 is an elevational view of the back end of a hub into which are fitted a pair of flat planar blades of preferred configuration pursuant to this invention.
FIG. 15 is a view of the upper blade of FIG. 14 looking in the direction of line 15,15 of FIG. 14.
FIG. 16 is a section of the upper blade of FIG. 14 taken along line 16,16 of FIG. 14.
FIG. 17 is an elevational view of the back end of a hub into which are fitted a pair of bent planar blades of preferred configuration pursuant to this invention, these blades being adapted for rotation in the clockwise direction (as viewed in this Figure).
FIG. 18 is a view of the upper blade of FIG. 17 looking in the direction of line 18,18 of FIG. 17.
FIG. 19 is a section of the upper blade of FIG. 17 taken along line 19,19 of FIG. 17.
FIG. 20 is an elevational view of the back end of a hub into which are fitted a pair of bent planar blades of preferred configuration pursuant to this invention, these blades being adapted for rotation in the counter-clockwise direction (as viewed in this Figure).
FIG. 21 is a view of the upper blade of FIG. 20 looking in the direction of line 21,21 of FIG. 20.
FIG. 22 is a section of the upper blade of FIG. 20 taken along line 22,22 of FIG. 20.
FIG. 23 schematically depicts in plan view the positioning of the planar blades in the fast forward position in a system involving clockwise rotation (as viewed in the direction of the arrow therein).
FIG. 24 schematically depicts in plan view the positioning of the planar blades in a reverse position in a system involving clockwise rotation (as viewed in the direction of the arrow therein).
FIG. 25 is an elevational view of the back end of a hub into which are fitted a pair of grooved tangential swept back flat planar blades of particularly preferred configuration pursuant to this invention.
FIG. 26 is a view of the upper blade of FIG. 25 looking in the direction of line 26,26 of FIG. 25.
FIG. 27 is a section of the upper blade of FIG. 25 taken along line 27,27 of FIG. 25.
FIG. 28 is a top plan view of the upper blade and the upper portion of the hub of FIG. 25.
FIG. 29 is a fragmentary section of the hub of FIG. 25 taken along line 29,29 of FIG. 28.
FIG. 30 is an elevational view, partly in section, of a hub and a pair of grooved tangential swept back flat planar blades with a preferred mechanism within the hub for rotating the blades on the axis of their respective stubs.
DESCRIPTION OF PREFERRED EMBODIMENTS
In order to still further illustrate the practice and advantages of this invention reference is now made to the Drawings in which like numerals represent like parts among the several views. The Drawings, which are not to scale, depict and illustrate only certain preferred forms of the invention. Other forms of the invention and apparatus provided thereby will be readily apparent from a consideration of this entire disclosure.
The Planar Blades of the Invention
Turning first to FIGS. 14 through 16, the flat planar blades 46 of this invention in the form therein depicted have a relatively sharp leading edge 51 and a relatively thick or blunt trailing edge 47. Each blade is affixed at its inner end as by welding or the like to a cylindrical stub 50 which is adapted to be axially rotated by adjusting means, preferably of the type described hereinafter. Such rotation allows the pitch of the blades to be adjusted. Hollow hub 45 contains some of the mechanism (not shown in FIGS. 14-16, but a preferred form of which is described hereinafter in connection with FIGS. 10, 11 and 30) for effecting such axial rotation. In the system as depicted in FIGS. 14-16, hub 45, and each blade 46 and its stub 50, are rotated in the direction of arrow 90 by a drive shaft and drive train (not shown in FIGS. 14-16, but a preferred form of which is described hereinafter in connection with FIGS. 3-11) so that leading edge 51 cuts into the water. It is to be understood that if the rotation by the drive shaft and drive train is arranged to be in the counter-clockwise direction (opposite to the clockwise direction of arrow 90) then each of the flat planar blades 46 of FIG. 14 would be rotated 180° on the axis of its stub 50 so that the positions of the leading edge 51 and the trailing edge 47 would be the reverse of the positions shown. The swept back configuration of leading edge 51 as depicted in FIG. 14 should be noted. Of this, more will be said hereinafter.
FIG. 15 illustrates the fact that in their most preferred form the respective faces 92 and 93 of flat planar blades 46 are essentially completely flat from inner end to outer end with only a small degree of curvature or taper or thinning outer as at 94a near the outer end. FIGS. 15 and 16 illustrate the fact that in their most preferred form the respective faces 92 and 93 of flat planar blades 46 are likewise essentially completely flat from leading edge 51 to trailing edge 47, but that the thickness of the blade is more or less progressively increased from thin edge 51 to thick edge 47. The forward edge portion of the blade may additionally be sharpened or thinned out even more near the leading edge 51 as at 94b. Trailing edge 47 may be squared off (as shown) or it may be rounded off so that there are no relatively sharp corners. Likewise it may be tapered down in thickness. In short, the thicker portion of the blade is either at the trailing edge of the blade or is somewhere between about the median portion of the blade and its trailing edge. The presence of the thicker portion of the blade is to insure that the blade has sufficient strength to apply the necessary force against the water to propel the boat. For best results face 92--the face away from the rear of the boat--should be flat and any taper or the like should be in face 93 (such as is depicted in FIGS. 15 and 16). The blade may be be thin and completely uniform in cross section (e.g., 1/32 inch) if made from a material having sufficient strength to propel the boat without becoming distorted or undergoing physical deterioration (fatigue) after prolonged usage.
FIGS. 17 through 19 depict in a preferred configuration bent planar blades 46a. It can readily be seen that these bent planar blades can possess all of the structural features as the flat planar blades just described, but differ therefrom in that they possess a progressive bend along their outermost portions. This bend preferably commences at a locus 95 which is between about 1/2 to about 3/4 (most preferably about 2/3) the distance from the inner end and the outer end of the blade. The blades depicted in these Figures are adapted for use in propulsion systems in which the propeller shaft and hub 45 rotate clockwise (when viewed from a location behind the boat and propeller) in the direction of arrow 97. Thus in this case the relatively thin leading edge 51 of the upper blade in FIG. 17 (the blade in the 12 o'clock position) is on the right hand side of FIG. 17, since this is the direction toward which the blade is rotated by rotation of the propeller shaft. When this same blade is rotated to the 6 o'clock position (the position of the lower blade in FIG. 17), its leading edge will of course be toward the left hand side of that Figure. As FIG. 18 indicates, the bend of planar blades 46a,46a is toward the front of the boat (i.e., toward the direction in which the boat normally travels). It will be seen that both blades 46a,46a are of the same geometrical and structural configuration--they are interchangeable with each other. Therefore, for systems in which the rotation is clockwise, only one type of blade-- a blade preferably configured as blade 46a in FIGS. 17-19--need be manufactured and maintained in inventory, and moreover in the event one blade is damaged it can be replaced without need for relacing the entire propeller assembly as is often the case. Nevertheless, to insure optimum performance it may be desired to substitute a matched pair of new replacement blades in the event one of the blades in the system becomes damaged.
Once again the swept back configuration of leading edge 51 as depicted in this case in FIG. 17 should be noted. Of this, more will be said hereinafter.
FIGS. 20 through 22 depict in a preferred configuration bent planar blades 46b. It can be readily be seen that these bent planar blades possess all of the structural features as the bent planar blades 46a just described, but differ therefrom in that the positions of the leading edge 51 and the trailing edge 47 are reversed relative to the progressive bend along their outermost portions. As in the embodiment depicted in FIGS. 17-19, this bend preferably commences at a locus 95 which is between about 1/2 to about 3/4 (most preferably about 2/3) the distance from the inner end and the outer end of the blade. However the blades depicted in FIGS. 20-22 are adapted for use in propulsion systems in which the propeller shaft and hub 45 rotate counter-clockwise (when viewed from a location behind the boat and propeller) in the direction of arrow 99. Thus in this case the relatively thin leading edge 51 of the upper blade in FIG. 20 (the blade in the 12 o'clock position) is on the left hand side of FIG. 20, since this is the direction toward which the blade is rotated by rotation of the propeller shaft. When this same blade is rotated to the 6 o'clock position (the position of the lower blade in FIG. 20), its leading edge will of course be toward the right hand side of that Figure. As FIG. 21 indicates, the bend of planar blades 46b,46 b is toward the front of the boat (i.e., toward the direction in which the boat normally travels). It will be seen that both blades 46b,46b are of the same geometrical and structural configuration--they are interchangeable with each other. Therefore, for systems in which the rotation is counter-clockwise, only one type of blade--a blade preferably configured as blade 46b in FIGS. 20-22--need be manufactured and maintained in inventory, and moreover in the event one blade is damaged it can be replaced without need for relacing the entire propeller assembly as is often the case. Here again, to insure optimum performance it may be desired to substitute a matched pair of new replacement blades in the event one of the blades in the system becomes damaged.
FIGS. 14, 17, and 20 illustrate a very important feature of the planar blades of this invention, namely that the leading edge 51 is swept back or retracted for a substantial portion of its length (preferably more than 50% of the distance from inner end to outermost end). This permits the blade to slice through the medium in which it being rotated and thus a substantial portion of the leading edge does not confront the medium head-on or tend to force the medium inwardly toward the hub, but rather a substantial portion of the leading edge tends to force the medium outwardly away from the hub. This may explain why such blades are able to cut through wet mud and vegetation under conditions where a helically-twisted or even a paddle-shaped or rectangularly-shaped blade could not operate. Whatever the mechanism or explanation, this feature has been found in actual practice to greatly reduce the incidence of boats becoming mired and bogged down when operating in wet mud or in thickly overgrown marshy areas.
FIGS. 23 and 24 schematically illustrate how the pitch of the planar blades 46 (whether they are flat planar blades 46 or bent planar blades 46a or 46b) can be adjusted for forward and rearward travel, respectively. In these Figures the drive shaft 14 (shown for simplicity as a line) and hub 45 are caused to rotate in a clockwise direction when viewed in the direction of arrow 65 (i.e., viewed from a location behind the boat and propeller, and looking toward the direction in which the boat normally travels). The leading edge 51 of blade 46 (shown for simplicity as a line) is thus toward the top of these Figures since these Figures are plan views with the viewer of course looking down at the system depicted. In FIG. 23 planar blade 46 is in a fast forward position with angle beta being as much as 45°. In FIG. 24 planar blade 46 is in a reverse position with angle gamma being as much as 45°, but preferably no more than about 25°. When blade 46 is axially rotated so that its plane coincides with transverse plane 85 (i.e., angle beta in FIG. 23 and angle gamma in FIG. 24 is 0°), the blades are in their neutral position and the boat is neither driven forward or in reverse. The preferred system of this invention enables these changes in blade pitch to be made quickly, easily and safely through a continuum of positions ranging from fast forward (FIG. 23) to reverse (FIG. 24). Thus flat bottom boats even when operated in thickly vegetated, muddy marshes can now be maneuvered so that they do not become stuck or mired. Persons in south Louisiana having first-hand familiarity with the problems that can be encountered in such operation have expressed, often spontaneously, and occasionally in less than polite language, their utter amazement at the handling characteristics and maneuverability and performance of a flat bottom boat equipped with a preferred system of this invention utilizing a pair of flat planar blades 46 and a mere 18 hp gasoline engine as the power source.
A most preferred planar blade construction pursuant to this invention is illustrated in FIGS. 25 through 29 to which attention is now invited. Depicted in these figures are the grooved tangential swept back flat planar blades of this invention. It can be seen that in this configuration the blades possess the swept back (retracted) leading edge feature and otherwise resemble the blades of FIGS. 14-22 described above except that the inner portion of leading edge 51 projects substantially tangentially from hub 45 for part of the distance from inner end toward the outer end (i.e., along segment "T") when the blades are in or close to their neutral position (depicted in FIG. 28) where the blade is transverse or substantially transverse to the axis of the drive shaft (not depicted in FIGS. 25-29) and of hub 45. In addition, the inner end of the leading edge portion fits into an arcuate groove 77 shaped to permit and accommodate rotation of the blade in either direction from neutral (as depicted by arrows 98 in FIG. 28). To facilitate an understanding of this grooved construction, arcuate groove 77 is depicted in plan in FIG. 28 as if the groove is in a flat planar surface rather than being cut into the surface of a cylindrical surface of hub 45, which in fact it is. The distortion of arcuate groove 77 when viewed in a plan view as it actually exists in the cylindrical surface of hub 45 might tend to be somewhat confusing, hence the simplification for the sake of better communicating the concepts involved in the actual construction. In this same connection, it will be appreciated that another such groove would be provided for each blade carried by the hub, in this case one additional groove (not shown) for the blade extending from the opposite side of hub 45.
The respective ends 79 of groove 77 serve as stops to prevent over-rotation of the blade in either such direction. As can be appreciated (and as indicated in FIG. 29) groove 77 becomes deeper when proceeding in the direction of midpoint (i.e., transverse to the axis of hub 45) to the respective ends 79,79. The planar blades of this invention which include these tangential and grooved configurations possess all of the advantageous features of the blades of FIGS. 14-22, but additionally have the advantage that vegetation and other debris rarely if ever become entangled with the blades or wedged between the blades and hub. As a consequence, these particularly preferred blades enable operation in swamps with an efficiency which, to the best of our knowledge and belief, has never been achieved heretofore with any other propeller design, drive system and engine of equal horsepower.
As will be appreciated by those skilled in the art, the amount of surface area of the blades used should not require driving power in excess of the power available from the engine or other prime mover being used to supply the power needed to propel the boat under the service conditions to be encountered. If, in other words, the blades are too large to be effectively driven through the water or wet mud or vegetation-rich swamp by a given engine, one should either use smaller blades of the same configuration or a more powerful engine, or both, so that the prime mover has the capacity to effectively propel the boat under the service conditions to be encountered. On the other hand, the surface area of the blades should be large enough to take advantage and make effective use of the power available from the engine being used. The relationship between blade surface area and engine horsepower to achieve best performance will depend on various factors such as the size and shape of the boat hull, the number of blades being used, the load to be carried in the boat, the frictional characteristics of the drive train, the density of the wet mud and foliage in which the boat may be operated, and so on. The following relationships, which are presented for purposes of illustration and not limitation, should be of help in designing or selecting components for a two-bladed propeller and drive and pitch-adjusting system of the type described herein:
______________________________________ Approximate Number of Square Inches of Surface AreaEngine Horsepower for One Face of One Planar Blade______________________________________12-14 About 6 to about 718 About 8 to about 925 About 10 to about 11______________________________________
It will be seen that, generally speaking, the higher the horsepower, the larger the blade surface area. Thus with a 50 hp engine the most suitable blade surface area will be larger than about 11 square inches, and with 100 hp engines it will be larger still.
Referring again to FIGS. 25 to 29, another surprising feature of these particular blades is that when the surface area is adjusted as indicated in the above table and this surface area is properly apportioned between the areas fore and aft of centerline CL in FIG. 25 the best overall performance can be achieved. For example, with an 18 hp engine, a variable pitch control and drive system of the type described hereinafter, and with a pair of variable pitch grooved tangential swept back flat planar blades of the type depicted in FIG. 25 in which the ratio between area "A" to the foreward side of centerline CL and area "B" to the rearward side of centerline CL is about 45:55, there is no tendency for control lever 11 of the system described hereinafter (see FIGS. 1 and 2) to move in either direction even when not held in any given position by the operator. However the maximum boat speed is not obtainable from this particular system under these particular circumstances. When the same type of blade is slightly modified such that the ratio between area "A" to the foreward side of centerline CL and area "B" to the rearward side of centerline CL is about 42:58 again there is no tendency for control lever 11 to move in either direction even when not held in any given position by the operator, and in this particular case the boat can be operated smoothly at all speeds, including high speeds. When under these same conditions this same ratio is adjusted to about 40:60 very similar results are achieved except that there is a slight tendency for control lever 11 to move when not held in position by the operator, but only at the highest speeds of boat operation. And when under these same conditions this same ratio is adjusted to about 38:62, very high speed boat operation can be achieved but in this particular case and under these particular conditions there is a sufficient tendency for control lever 11 to move when not held in position by the operator that it is desirable to provide means for holding lever 11 in whatever position it is moved into by the operator. Each of the foregoing situations provides acceptable operation pursuant to this invention. Thus the selection of any given ratio as between area "A" and area "B" will depend on the type of operation and service sought to be designed into any given system. If speed is of paramount importance, a ratio such as 38:62 may be selected and means provided to lock lever 11 in whatever position the operator may select. On the other hand, if a system in which lever 11 is unrestrained and automatically stays where placed by the operator, but high speed operation is not an objective, a ratio of about 45:55 may be selected. An ideal compromise in order to achieve both high speed and unrestrained operation of lever 11 would involve use of a ratio of about 42:58. The foregoing relationships among engine horsepower, blade configuration, blade size and blade area distribution, which are presented for purposes of illustration and not limitation, should be of further help in designing or selecting components for a two-bladed propeller and drive and pitch-adjusting system of the type described herein.
Variable Pitch Adjusting System and Drive Mechanism
At the outset it is to be understood and appreciated that the blades of this invention can be effectively used with any suitable drive and pitch-adjusting system, such as those described in some of the patents cited hereinabove. However for best results a system of the type described hereinafter should be used, and the combination of the blades of this invention and a system of the type described hereinafter constitutes an especially preferred embodiment of this invention.
The preferred form of variable pitch and adjusting mechanism and drive system for use with the planar blades of this invention, in its preferred form depicted, is especially adapted for use with flat bottom mud boats utilizing a relatively small engine (e.g., up to about 25 hp) as the prime mover 10 (note FIG. 3). Platform 12 is disposed above the inner end portion of hollow drive shaft 14, and serves as a means for mounting prime mover 10 on the upper portion of the mechanism to conserve space within the boat (not shown). As best seen in FIG. 3, an endless belt 16 driven by pulley 18 passes over and rotates drive shaft 14. A pulley (not shown) may be affixed to drive shaft 14 to accommodate belt 16, if desired. Rotatable belt tensioner 20 is adjustably secured in position to enable the tension on belt 16 to be properly adjusted. Thus operation of prime mover 10 causes rotation of drive shaft 14 by means of belt 16.
Drive shaft 14 is rotatably secured along a portion of its length within shaft housing 22 by means of bearings (not shown). Drive shaft 14 is hollow along its length (note FIG. 6) and in the form depicted is affixed at its outer end to open-ended hollow housing 24 which is rotatable therewith. Mounted within drive shaft 14 is pitch adjusting rod or shaft 26 which is longitudinally slidable within bearings or bushings 28 secured within drive shaft 14. Shaft 26 and bearings or bushings 28 rotate in unison with drive shaft 14 and housing 24. Hub end cap 30 is adapted to be detachably secured to housing 24 by means of threaded studs 32 (which pass through matching apertures 34) and exteriorly affixed nuts 36. A pair of split bushings 38 are mounted and affixed (for example by welding) in matching recesses 40 on opposite sides of the outer end of housing 24, and a matching pair of split bushings 42 are mounted and similarly affixed in matching recesses 44 on opposite sides of the inner end of end cap 30. Thus when end cap 30 is secured to housing 24 there is formed a hollow hub 45 together with a pair of bearings formed from the respective opposed pairs of stationary split bushings 38,42. As seen from FIGS. 1 and 2, planar blades 46 are carried by hub 45.
Within hub 45 is contained means for translating longitudinal movement of shaft 26 into rotational movement of blades 46 around their own axes in order to change the pitch of the blades. Secured to the outer end portion of shaft 26 is yoke 48 comprising a pair of laterally spaced, axially projecting ear portions 49. Secured to the interior portion of each blade 46 is a cylindrical stub 50 having a lobe portion 52 integral therewith. As can be seen from FIGS. 10, 11 and 12, the lobe portions 52 extend radially along an axis perpendicular to the axis of stub 50 and thereby form a crank thereon. As shown by FIG. 11, the two lobe portions 52 extend in generally opposite directions, one extending generally upwardly and the other generally downwardly. A link 55 is pivotally mounted on and connects each of the repective lobe portions 52 to the transversely proximate ear portion 49 of yoke 48. Thus as viewed in FIG. 10 one of the links 55 is connected between the transversely remote ear portion 49 and the transversely remote lobe portion 52. It will be understood and appreciated therefore that the same linkage applies to the transversely proximate ear portion 49 and the transversely proximate lobe portion 52 (not shown in the sectional view of FIG. 10) nearer the viewer, except that the positions of this proximate link 55 and this proximate lobe portion 52 will be inverted as compared to those depicted in FIG. 10. Thus as indicated for example in FIGS. 10 and 12, longitudinal movement of shaft 26 causes rotation of the respective lobe portions 52 in opposite directions which in turn causes the respective stubs 50 and planar blades 46 to rotate around their axes in opposite directions so that the pitch of the planar blades can thereby be adjusted within a continuum of positions.
FIG. 30 depicts a hub 45 containing means as described above for translating longitudinal movement of shaft 26 into rotational movement of blades 46 around the axis of their respective stubs 50 in order to change the pitch of the blades. In FIG. 30 the blades are a pair of grooved tangential swept back planar blades of the type described hereinabove. The blades are attached to their respective stubs 51 by means of a ground weld as at 75.
A feature of this invention is illustrated in FIGS. 11 and 30, viz., the particularly preferred way in which the blade stubs 50 axially abut and rotatably engage each other. As depicted in FIGS. 11 and 30, the inner end of each stub 50 has an axially positioned cylindrical recess 58 thereby forming an annular face 59 on the end of each stub. The recesses are sized and shaped to slidably receive dowel 57 to keep both stubs in axial alignment. In addition, the opposed faces 59,59 abut each other around dowel 57. This construction provides a large area of slidable contact between the respective stubs and as explained hereinabove, it is believed that this coupling of opposed torsion derived forces imposed on the blades 46 as they are rotated in the water around the axis of shaft 14 tends to pit these counter-rotational forces against each other so that the selected pitch of the blades resists change caused by such forces except in extenuating circumstances such as a blade striking a heavy submerged object. In this same connection, FIG. 10 illustrates that while a longitudinal force imposed on shaft 26 will cause rotation of stub 50 and a change in the pitch of propeller blade 46, undesired longitudinal movement of shaft 26 tends to be resisted by the frictional contact between shaft 26 and bushing 28. Further, since the entire unit depicted in FIG. 10 is rotating around the axis of shaft 26, it is believed that centrifugal forces generated in such rotation tend to provide resistance against undersired longitudinal movement of shaft 26. It is to be understood and appreciated, however, that this invention is not intended to be limited, nor should it be limited, to any theory of operation. The invention has been found to work, and to work very well under actual service conditions, irrespective of the theoretical niceties of why it works.
Another important advantage of the construction depicted in FIG. 11 is the fact that both blade-stub assemblies are identical to each other, both in size and shape and weight. Thus if one planar blade is damaged during use, it can be replaced by another identical blade-stub assembly--there is no need to stock two differently constructed blade-stub assemblies. Moreover the fact that the two halves of the blade-stub assemblies are the same (except disposed in inverted positions relative to each other, as depicted) insures that the entire system is well balanced and will provide smooth operation. In this connection, it is desirable in the case of stainless steel blades to match the weight of the respective blade-stub assemblies to within about 1/2 of an ounce.
FIGS. 12 and 13 illustrate respective features of the planar blades. In one form the blades preferably have in transverse profile a convex shape as indicated in FIG. 12 whereas in other preferred forms they have a substantially flat transverse profile as indicated in FIG. 13. FIG. 13 illustrates still another preferred feature, namely that the blades, whether of a convex or flat generally planar profile, can have one relatively thick edge 47 and in any event do have one relatively thin edge 51, the latter serving as the leading edge. This feature has been found particularly desirable in mechanisms used in propelling mud boats in swampy or marshy areas. For example, with a pair of blades each having on one side a facial area of about ten square inches, one edge (the trailing edge) preferably has a thickness in the range of about 1/8 to about 3/8 inch, most preferably about 1/4 inch, whereas the other edge (the leading edge) should be sharp or relatively sharp, e.g., it is preferably no more than about 1/32 inch in thickness.
As depicted in FIGS. 1 and 2 control lever 11 is pivotally connected to the mechanism so that forward or rearward movement of the lever as indicated by the arrows in FIG. 1 causes longitudinal movement of shaft 26 and consequent adjustment in the pitch of the blades. As noted hereinabove, lever 11 need not be equipped with stops for specified intermediate positions, although such stops may be provided, if desired. It is however desirable to provide stops to confine the limits of forward and reverse travel of lever 11 so that the engine or other prime mover is not subjected to excessive speeds or stress during operation. In the system of FIGS. 25-30 the ends 79,79 of groove 77 can serve as stops.
FIG. 1 also illustrates the fact that for flat bottom boat operation the mechanism is preferably mounted on the boat so that its angle of rearward decline (angle alpha) from the horizontal is between about 10 and about 12 degrees, most preferably about 10 degree.
Other preferred features depicted in FIGS. 1 and 2 include the provision of an elongated mounting plate 15 above a substantial portion of shaft housing 22. Plate 15 is placed against the bottom of a flat bottom boat so that the propeller is below but close to the rear transom of the boat, and the overall mechanism of this invention is then bolted to the boat through apertures in plate 15 and the bottom of the boat. It will thus be appreciated that shaft housing 22 extends up into the boat through a suitable opening in the boat which is covered by plate 15. Keel or rod 17 which may be square, round, or etc. and either solid or hollow, is preferably about 5/8 to 3/4 inch in cross-section. It declines rearwardly somewhat more than angle alpha and thus as the boat is propelled forwardly, rod 17 tends to impose an upward lift in the event a submerged stump or other obstacle is encountered. Upper vertical plate 19 provides connection between the median lower portion of mounting plate 15 and the median upper portion of shaft housing 22. Lower vertical plate 21 provides connection between the lower median portion of shaft housing 22 and the median upper portion of rod 17.
As can be seen from FIGS. 1 and 2, affixed to the rearward portion of shaft housing 22 are a pair of elongated triangular fins 23,23 which extend radially outwardly from opposite sides of the exterior of housing 22. As depicted in FIG. 2, each such fin provides in profile (i.e., when viewed from above) an inclined plane of progressively increasing height terminating in front of and in proximity to the transverse circular locus of rotation of blades 46,46. The apex of this triangular profile extends (as depicted) to at least about the midpoint of the radial length of the blades to the extent they project from hub 45. These fins assist in preventing fouling when operating in marshy areas thick with grasses and other plant life.
The boat itself may be made of metal such as aluminum, plastics, laminates, wood or the like.
Boats equipped with systems of this invention are generally operated at conventional engine speeds, e.g., about 2500 to about 3200 rpm, and at slower idle speeds. Among the advantages of this invention is the fact that the system may be shifted very easily, smoothly, and rapidly from full speed forward to full speed reverse without changing engine speed--none of this is possible with conventionally equipped power boats.
This invention thus makes possible the following advantages:
1) Fouling of propeller blades can be avoided even when operating in thickly vegetated marshy areas.
2) Boats can be maneuvered such that they can extricate themselves from mud and vegetated areas in which conventional boats would become mired and bogged down.
3) Boats can be operated at a wide range of speeds, both in forward and in reverse.
4) Boats can be stopped easily, rapidly and smoothly, and can be caused to reverse directions, all without changing engine speed.
5) Systems can be provided in which conventional restraining means for the pitch control lever need not be used.
6) Durable systems easy to service and maintain can be provided.
7) Very quiet boat operation is readily achieved.
8) Ordinary low to medium horsepower engines can be used.
9) Systems can be provided which do not occupy much boat space.
This invention is susceptible to considerable variation in its practice and it is not intended that it be limited by the illustrative embodiments described herein. Rather, this invention is embodied in the spirit and scope of the ensuing claims. | A propeller blade having (i) a planar configuration (ii) an inner end portion, (iii) an outer end portion, (iv) a relatively sharp, outwardly swept back leading edge portion, and (v) a cylindrical stub axially aligned with the plane of the blade and affixed to the inner end portion of the blade. Also described is a mechanism that enables the pitch of the blades to be adjusted by the operator through a continuum of positions ranging from fast forward to fast reverse so that the boat can be operated at a full range and variety of speeds, can be stopped rapidly, and can be maneuvered with precision. The mechanism can be used for operating flat-bottom boats ("mud boats") in swamps, shallow water, bayous, lakes, rivers and the like, and pass through wet mud and swampy marshes choked with mud or vegetation without excessively fouling the propellers. The mechanism can be serviced and repaired easily and quickly, and can be employed to operate small craft such as mud boats with a minimum loss of interior boat space. | 1 |
BACKGROUND OF THE INVENTION
1. The Field of the Invention
The present invention relates to the use of low frequency energy (in the acoustic range) to selectively affect the permeability in a reservoir to control fluid flow and, in particular, to a technique involving the use of synchronized vibratory sources spaced in a patterned array with respect to the reservoir to impart low frequency energy which can be focused selectively on localized zones within the reservoir.
2. The Prior Art
It is well known to use acoustic wave energy for the purpose of making seismic surveys, see U.S. Pat. No. 4,008,459 for example. It is also well known to impress a coding format on these acoustic wave signals to obviate problems with interference and/or false returns, see U.S. Pat. No. 4,969,129 for example. It is further well known to place acoustic wave generating sources down well bores and to conduct seismic surveying subsurface between wells, see U.S. Pat. No. 5,042,611 for example. However, no one to date has proposed to apply acoustic wave energy to a formation in such a manner as to improve the production therefrom.
There are a number of publications which suggest that the application of acoustic energy to a reservoir can possibly have an effect on the volume of fluids produced therefrom. This phenomena is not well understood and is not commonly used in the United States at this time. Although work was done in the area in the United States over twenty years ago, it was not subsequently actively pursued. The technique has been used to some extent in the former Soviet Union. There has been a recent revival of interest in this concept in the United States by several major oil companies.
SUMMARY OF THE INVENTION
The present invention improves the flow rate of fluid in a reservoir by providing a patterned array of acoustic devices about the reservoir and selectively energizing them in such fashion that the vibrational energy can be directed throughout the reservoir to focus in designated regions to encourage fluid flow other than through channels formed during conventional enhanced oil recovery operations. The vibratory energy sources can be synchronized to direct the resultant waves. The acoustic sources can be arranged in arrays at the surface (planar), in arrays suspended in a plurality of well bores (vertical), or in combination of surface (planar) and in-well (vertical) arrays.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described, by way of example, with reference to the accompanying drawings in which:
FIG. 1 is a schematic representation of a vertical section though a typical producing field with, in accordance with the present invention, a patterned array of acoustic wave generators at the surface and adapted to focus acoustic energy subsurface;
FIG. 2 is a schematic, similar to FIG. 1, showing a variation of the present invention with a plurality of acoustic wave generators suspended downhole; and
FIG. 3 is a schematic, similar to FIGS. 1 and 2, showing a further variation of the present invention with a combination of surface and down hole acoustic wave generators.
DETAILED DESCRIPTION OF THE INVENTION
The present invention utilizes a plurality of acoustic wave generators in a patterned array and means for controlling the acoustic wave generators in such fashion that the combined waves generated produce a controlled and defined acoustic wave pattern subsurface. It is possible to direct nodes formed by the acoustic waves, at points where the acoustic waves meet, by varying the output of individual acoustic wave generators.
A first embodiment is shown in FIG. 1 wherein an array of acoustic wave generating sources 10, 12, 14 are placed in a patterned array with respect to a subsurface fluid reservoir 16. These acoustic wave generating sources, which can be selected from any of the well known types, are shown arranged in a planar array along the surface 18 of the earth. Acoustic wave generator control means 20 is provided operatively connected to energize the acoustic wave generating sources. The sources can be energized selectively, in synchronization, with various powers, with different frequencies, in different combinations or in any other known fashion to produce the desired subsurface acoustic wave patterns. Thus it is possible to produce a controlled and defined acoustic wave pattern selectively within any specific zone of the reservoir 16. The acoustic waves 22, 24, 26 emanating from the respective acoustic wave generating sources 10, 12, 14 will form a plurality of controlled nodes by adding in some regions while cancelling in other regions. By adjusting the relative phases and frequencies of the respective acoustic wave generating sources, it is possible to selectively steer the nodes of maximum amplitude to specific places in the reservoir.
An alternative embodiment is shown in FIG. 2 with a plurality of well bores 28, 30, 32 each having an acoustic wave generator 34, 36, 38, respectively, suspended therein. These generators produce acoustic waves 40, 42, 44, respectively.
A further alternative embodiment is shown in FIG. 3 combining both surface mounted and well bore suspended acoustic wave generator sources. For convenience, like reference numerals have been used in FIG. 3 for like features and components appearing in FIGS. 1 and 2.
The acoustic waves can be generated either as steady signals or in short periodic pulses. Preferably they should be in the frequency range of 20-100 Hz for the surface mounted generating sources and 300-2000 Hz for the subsurface suspended generating sources in order to achieve wave prorogation over a reasonable distance in the reservoir field.
By selectively focusing the acoustic energy in a specific region, it should be possible to encourage fluid flow of hydrocarbons in the reservoir through channels other than those formed during standard enhanced oil recovery operations. The passage of the acoustic waves through the formation should have a controlling effect on the rate of chemical reactions involved in the various known well treatment chemicals and/or foaming agents injected during enhanced oil recovery operations. The present invention should provide a means to cause the desired chemical action of a known secondary recovery treatment to occur in specific regions where that treatment is required. The acoustic waves could also be used to influence the direction of flow taken by the injected chemicals.
It should be noted that there are two basic embodiments of the present invention, which embodiments could be used either separately or in combination as a third embodiment. The first embodiment provides an array formed by a plurality of acoustic wave generating sources distributed about the surface over a known reservoir. The second embodiment provides a plurality of acoustic wave generating sources suspended in an array of boreholes throughout the reservoir site. Each suspended array can have more than one acoustic wave generating source. The combination would be to have acoustic wave generating sources both at the surface and suspended in selected boreholes thereby creating a three dimensional array of acoustic wave generating sources.
There are a number of reservoir parameters which must be determined and which could be critical to the effective use of the present invention. For example, mud filtration damage reduction, fines migration damage reduction, flow enhancement, paraffin damage removal, polymer completion fluid damage reduction are all considerations which must be taken into account. Each of these reflect on the condition of the reservoir from prior treatment and which would have a direct effect on the application of the present invention to that reservoir.
The formation of scale and various other deposits in production and injection wells has been a recognized problem for many years. This problem arises because moving fluids carry with them, or gather enroute, various minerals and chemical elements indigenous to their originating or surrounding environment. These minerals and/or elements may remain in solution and/or suspension as long as the physical conditions in the reservoir remain reasonably constant, namely, temperature, pressure, saturation level, rate of flow, etc. Changes in one or more of these conditions can allow the minerals and/or elements to precipitate or unite with other chemical forms causing a deposition of scale at the point of change. The buildup of scale is generally found formed in the wellbore, at the face of the formation, and for some limited radius around the wellbore into the formation, thus plugging off or sealing off the wellbore from the producing formation. In the past this condition has been treated mainly by further chemical operations or by mechanical methods including scrapers and reamers and explosive devices to create fracturing of the strata.
The present invention employs continuous application of high or ultra high frequencies upon the reservoir. The continuous influence causes extreme acceleration of molecular activity and sympathetic or resonant sonic pockets (nodes) begin to form in the material or transmitting medium. Given sufficient energy dissipation, this agitation can be increased to a point beyond material endurance and destruction occurs separating and breaking up the scale. Utilizing transducers, such as ceramic sonic generators, it was found that while the high frequency agitation performed well on thin scales, the effects were attenuated rapidly with penetration. Another drawback was that continuous power levels sufficient to destroy heavier accumulations tended to cause by the failure of the transducers.
Primary and secondary oil recovery efforts have historically been hampered by localized permeability damage caused by deposition of scale and other plugging materials. The heretofore methods for removing these plugging materials have been inadequate and the results generally are rather short lived. The application of sonic energy can be used to remove the deposits that are relatively unaffected by previous methods. It is to be expected that the present invention will have a longer lasting effect on correcting this situation.
It is to be understood that the acoustic generators can be designed to generate focused beams which then can be directed to intersect with similar beams at a particular substrate location to solve a particular problem, such as the abovementioned scale or deposition of materials.
The present invention may be subject to many modifications and changes without departing from the spirit or characteristics thereof. The present embodiments should therefore be considered in all respects as illustrative and not as restrictive as to the scope of the invention as defined by the appended claims. | A method for selectively affecting the permeability of reservoirs to enhance fluid flow therein includes placing a plurality of acoustical wave generator means in a patterned array with respect to the reservoir and energizing them to create acoustic nodes at targeted areas of the reservoir. The acoustic wave generator means can be located solely on the surface, only below surface or in combination above and below surface. The acoustic wave generator means can be selectively simultaneously or sequentially energized to create nodes at targeted areas of the reservoir. | 4 |
BACKGROUND OF THE INVENTION
This invention relates to a process for forming selectively an Al film or a silicon substrate by chemical vapor deposition, an Al selective deposition material to be used in the process and a process for preparing the same.
DESCRIPTION OF THE RELATED ART
Selective growth of Al film is applied, for example, in the formation of interconnection on a semiconductor substrate so as to achieve higher densification or planarization of the interconnection by filling the fine through-holes which has been impossible by the conventional sputtering process and to reduce the interconnection resistivity by application of an Al film to a polycrystalline silicon interconnection.
As the selective growth of Al film, a process using triisobutyl aluminum ((i--CH 4 H 9 ) 3 Al) has been reported as described in the Extended Abstracts of the 18th Conference on Solid State Devices and Materials (1986), pp. 755-756. In this process, selective formation of Al film is achieved by depositing Al selectively by means of chemical vapor deposition (CVD) onto the exposed portions of a silicon substrate having a silicon oxide pattern formed thereon.
However, the conventional process of the selective formation of Al films using triisobutyl aluminum suffers practical problems that the vapor pressure of the starting material triisobutyl aluminum is as low as 0.5 Torr at 25° C., and thus a sufficient amount of starting material cannot be fed, retarding the film formation speed by about two figures compared with that in the sputtering process currently employed in the processing of semiconductors, and that the starting material gas must preliminarily be subjected to vapor phase cracking.
No successful selective deposition of Al by thermal CVD using trimethyl aluminum has so far been reported. Although it was confirmed by the experiments made by the present inventor that the thermal CVD using dimethyl aluminum hydride can achieve such selective deposition, this process suffer problems that the selectivity is not necessarily exhibited to a sufficient level and further the resistivity of the thus formed Al film is greater than the one formed by the conventional process using triisobutyl aluminum (approximately the same as the ideal bulk resistivity).
SUMMARY OF THE INVENTION
This invention has been accomplished with a view to overcoming the problems inherent in the conventional processes and is directed to provide a process for selectively forming with high selectivity an Al film at a high deposition rate, an Al selective CVD material and a process for preparing the same.
One aspect of this invention to provide a process for selectively forming an Al film by means of chemical vapor deposition at the uncoated portions of a substrate coated with a masking material, characterized in that a molecular compound of trimethyl aluminum and dimethyl aluminum hydride is used as a starting material gas.
Another aspect of this invention is to provide an Al selective CVD material characterized in that it is an organic Al compound represented by the following formula:
(CH.sub.3).sub.3 Al--(CH.sub.3).sub.2 AlH
obtained through intermolecular binding between trimethyl aluminum and dimethyl aluminum hydride.
A further aspect of this invention is to provide a process for preparing the organic Al selective compound, which comprises mixing liquid trimethyl aluminum with liquid dimethyl aluminum hydride in an inert gas atmosphere, followed by vacuum distillation of the mixture to give the desired compound represented by the formula:
(CH.sub.3).sub.3 Al--(CH.sub.3).sub.2 AlH
obtained through intermolecular binding between the trimethyl aluminum and the dimethyl aluminum hydride.
This invention will better be appreciated by reading the following detailed description of the invention referring to the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a constitution of an exemplary apparatus to be used for selective formation of an Al film according to one embodiment of this invention;
FIG. 2a-2c shows mass spectra of the Al selective CVD material (2a) and of the starting materials (2b, 2c) thereof to be used according to this invention;
FIG. 3a-3b the molecular structures of the Al selective CVD material (3b) and of the starting material (3a) thereof; and
FIG. 4 is a flow chart showing an exemplary process for preparing the Al selective deposition material to be used according to this invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In this invention the molecular compound of trimethyl aluminum (hereinafter abbreviated as TMA) and dimethyl aluminum hydride (hereinafter abbreviated as DMAH) is used as a starting material gas.
It was confirmed that the molecular compound of TMA and DMAH can form an Al film having excellent electrical conductivity with good selectivity and at a high film formation rate as the Al selective CVD material.
the vapor pressure of the starting material gas is relatively as high as the intermediate value of TMA's (12 Torr, 25° C.) and DMAH's (2 Torr, 25° C.). Accordingly, the feed of the raw material can be increased by the order of 1 to 2 figures compared with that of the conventional triisobutyl aluminum. It is known by experiments that at the temperature where the raw material shows selectivity, the film formation rate increases with the increase of feed, although the rate is not absolutely determined by the feed. Thus, the increase of feed can achieve increase of film formation rate by the order of one figure.
According to the new finding made by the present inventor after experiments, use of the molecular compound of TMA and DMAH is as a whole superior to the single use of DMAH in terms of selectivity and resistivity (approximately the same as bulk resistivity) of the Al film selectively deposited.
In the third aspect of this invention to prepare the molecular compound of TMA and DMA, while a liquid TMA and a liquid DMAH are mixed, followed by distillation with heating, this action can be explained as follows.
TMA and DMAH are dimers which are stable at room temperature. As described in Journal of American Chemical Society, p. 3121 (1967), the TMA dimer has a bridge structure with the aluminum atoms being crosslinked via carbon atoms; whereas the DMAH dimer has a bridge structure with the aluminum atoms being crosslinked via hydrogen atoms as described in Chemical Communications p. 480 (1971). In the case of DMAH, since it has methyl groups in the molecule, the carbon atoms thereof can possibly be utilized in the crosslinking. However, the fact that hydrogen atoms are actually utilized in the crosslinking seems to prove better energy stability of the hydrogen atoms in achieving the crosslinking.
The crosslinking achieved via hydrogen atoms is more stable than in the crosslinking achieved via carbon atoms. Therefore, the TMA-DMAH molecular compound is more stable than the TMA dimer and a little less stable than the DMAH dimer, since the crosslinking in TMA-DMAH molecular compound is achieved via a hydrogen atom and a carbon atom.
When a mixture of TMA and DMAH is heated, the TMA dimer and DMAH dimer both undergo separation, and recombination of TMA and DMAH occurs to form a TMA-DMAH molecular compound; wherein by using the DMAH in a molecular weight of at least twice as much as the molecular weight of TMA, a mixture of DMAH dimer which is stabler than the TMA dimer and TMA-DMAH molecular compound which is stabler than the TMA dimer is resulted. At this temperature, since the vapor pressure of TMA-DMAH molecular compound is higher than that of DMAH, the TMA-DMAH molecular compound can be separated by vacuum distillation utilizing the difference in the vapor pressures.
Now preferred embodiments of this invention will be described referring to the drawings.
Application of the present Al selective CVD material to selective CVD will first be described. FIG. 1 shows a constitutional view of a gas mixer and a vacuum CVD apparatus to be used for selective formation of an Al film; wherein 1 is a carrier gas tank, 2 a mass flow controller for controlling the flow rate of a carrier gas, 3 a bubbler vessel for mixing the starting material with the carrier gas, 4 a temperature adjuster for controlling the vapor pressure of the starting material in the bubbler, 5 a growth chamber, 6 a wafer, 7 a heater for adjusting the temperature of the wafer, and 8 an evacuation system.
The TMA-DMAH molecular compound is sealed in the bubbler vessel 3, and hydrogen gas is introduced thereto from the carrier gas tank 1 to mix it with the vapor of raw material in the bubbler vessel 3 under control of the hydrogen gas flow rate by the mass flow controller 2. The mixture is then introduced to the growth chamber 5 whose pressure is reduced to several Torr by the evacuation system 8.
In this process, the pressure in the growth chamber 5 is maintained to 1 Torr, and the carrier gas of hydrogen is controlled to 60 SCCM (cm 3 /min as measured at 0° C. in terms of 1 atm) by the mass flow controller 2, with the temperature of the bubbler vessel 3 being maintained to 25° C. by the temperature adjuster 4; wherein the partial pressure of the raw material gas in the growth chamber is estimated to be 0.1 Torr. The wafer 6 placed in the growth chamber 5 is maintained by the heater 7 to the temperature where the starting material can show selectivity. The raw material introduced to the growth chamber 5 is heated on the wafer 6 to deposit Al thereon through pyrolysis.
Selective CVD was carried out using the TMA-DMAH molecular compound and DMAH, respectively, under the same conditions to compare film deposition rate, resistivity, surface condition and composition. The results are shown in Table 1.
TABLE 1______________________________________Comparison of TMA-DMAH molecular compound andDMAH in the film forming properties Starting material TMA-DMAH molecularEvaluation items compound DMAH______________________________________Deposition rate ca. 0.12 ca. 0.22(μm/min)Resistivity 3.6 ± 0.1 7.0 ± 1.2(μΩ · cm)Impurity content(atom %)Si 0.02 1.2C 0.2 0.8O 0.8 2.2H 0.1 0.3Surface roughness 25 75(nm)______________________________________
As shown in Table 1 both TMA-DMAH molecular compound and DMAH showed relatively high deposition rates (about 0.12 μm/min vs about 0.22 μm/min). Resistivity of the TMA-DMAH molecular compound (ca. 3.6 μΩ·cm) was higher than that of DMAH (ca. 7 μΩ·cm), and the reason for the higher resistivity of DMAH seems to be attributable to the impurities contained in the film and roughness thereof. The impurity contents in the film was determined by SIMS analysis for the depth profiles of Si, C, O and H. As for the impurity contents in the Al films, DMAH showed higher Si concentration than in TMA-DMAH molecular compound by two figures, and several times higher concentrations of the other impurities. Selectivities of the two were compared by the number or density of the islands per unit area observable by an optical microscope (magnification 700). The island density when the TMA-DMAH molecular compound was used is by far smaller than when DMAH was used.
When CVD was carried out using the TMA-DMAH molecular compound on a silicon substrate having a silicon oxide pattern formed thereon, Al was deposited with good selectivity on the exposed portions of the silicon substrate through the opening of the masking pattern; wherein it was confirmed that sufficient selectivity can be exhibited in the temperature range of 220° to 250° C.
The effect of this invention can also be obtained by using other materials such as SiNx and PSG instead of the silicon oxide as used in the above embodiment. Further, while hydrogen was used as the carrier gas in the above embodiment, the effect of this invention can also be exhibited by use of argon or helium.
Incidentally, the means for feeding the TMA-DMAH molecular compound is not limited to the one exemplified in this embodiment, and as another effective means, for example, the two gas phase components can be transported from a bubbler having a TMA solution sealed therein and a bubbler having DMAH solution sealed therein using hydrogen as a carrier gas, respectively, to be mixed at a section immediately upstream the growth chamber 5.
Next, the properties of the raw material gas used for Al selective CVD will be described.
FIG. 2-(a) shows a mass spectrum of the vapor phase component of the TMA-DMAH molecular compound which is the Al selective CVD material of this invention containing helium as a carrier gas determined by quadruple mass spectrometer. For the purpose of comparison, FIGS. 2-(b) and 2-(c) show mass spectra of TMA and DMAH, respectively.
The axis of ordinates show ion current and the axis of absissas shows mass/unit electric charge (m/e). The same peaks of ion current were observed in all of these spectra at m/e=2, 15, 16, 27, 42, 43 and 57. The fragment observed at m/e=4 is of the helium carrier gas, while the fragments at m/e=17, 18 and 28 are of background impurities.
A fragment specific to the TMA-DMAH molecular compound (mass=130) is observed at m/e=115, which is of the (CH 3 ) 4 Al 2 H + separated from the TMA-DMAH molecular compound upon fragmentation.
On the other hand, a fragment is observed at m/e=129 in the mass spectrum pattern of TMA shown in FIG. 2-(b), which is of the (CH 3 ) 5 Al 2 + separated from the TMA dimer upon ionization. Fragments specific to DMAH are observed at m/e=101 and 115 in the mass spectrum pattern of DMAH, which are of the (CH 3 ) 3 Al 2 H 2 + and of the (CH 3 )) 4 Al 2 H + separated from the DMAH dimer (mass+116), respectively.
The TMA-DMAH molecular compound can be determined by the presence of fragment at m/e=115 from the mass spectrum of the starting material gas.
Now, the chemical structure of the TMA-DMAH molecular compound will be discussed. As described in Chemical Communications, p. 480 (1971), the DMAH dimer has been proved to have a bridge structure where the two Al atoms are crosslinked via hydrogen atoms by electron beam diffraction as shown in FIG. 3-(a). Thus, it can be seen that the Al atoms can be crosslinked more stably by hydrogen atoms than by methyl groups. Accordingly, it can be concluded that the TMA-DMAH molecular compound has a structure where the two Al atoms are linked via a methyl group and a hydrogen atom.
Next, the present process for preparing the Al selective CVD material will be described. FIG. 4 is a flow chart showing the process for preparing the Al selective CVD material to be used according to this invention. The entire process is carried out in an inert gas atmosphere or in an atmosphere where only the starting materials are present, since TMA, DMAH and the product to be formed therefrom are readily reactive with water and oxygen.
A liquid TMA and a liquid DMAH are weighed, respectively, at the weight ratio of the former to the latter of 3:7 at room temperature and they are mixed by stirring. The mixing can be carried out with heating to accelerate formation of the molecular compound, and vacuum distillation was used in this embodiment under the conditions of 46° C. temperature and 50 Torr pressure. The thus obtained TMA-DMAH molecular compound can form an Al film having good electrical conductivity by thermal CVD with excellent selectivity.
As described heretofore, this invention provides a process for forming an Al film by CVD using an Al selective deposition material which can form with high selectivity an Al film having good electrical conductivity without subjecting it preliminarily to cracking.
Further, according to the process of this invention the Al selective deposition material can easily be prepared from TMA and DMAH which has conventionally been used. | This invention provides a process for forming with high selectivity an Al film having good electrical conductivity at the uncoated portions of a substrate coated with a masking material by means of chemical vapor deposition, using an Al selective deposition material having good electrical conductivity without subjecting it preliminarily to cracking, characterized in that the process employs a molecular compound of trimethyl aluminum and dimethyl aluminum hydride as a starting material gas. This invention also provides an Al selective CVD material characterized in that it is an organic Al compound represented by the following formula:
(CH.sub.3).sub.3 Al--(CH.sub.3).sub.2 AlH
obtained through intermolecular binding between trimethyl aluminum and dimethyl aluminum hydride. This invention further provides a process for forming the Al selective CVD material which comprises mixing a liquid trimethyl aluminum with a liquid dimethyl aluminum hydride in an inert gas atmosphere, followed by vaccum distillation of the mixture to give the desired compound represented by the above formula. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates to vehicle garnishes. Specially, to a garnish designed to cover a hinge arm attached to a deck lid covering a vehicle's trunk.
BACKGROUND OF THE INVENTION
[0002] Garnishes have been used to cover various parts and components of vehicles for quite some time. Garnishes help to separate the user or occupant of the vehicle from mechanical, electrical, and structural components of the vehicle. Garnishes provide a physical barrier that protects the vehicle and the passengers, while at the same time providing an appearance that is more refined and luxurious.
SUMMARY OF THE INVENTION
[0003] The present invention is a garnish that is specially designed to cover a hinge arm connecting a vehicle truck lid to the vehicle. The garnish includes a cover that has an inside surface, an outside surface, a first end and a second end. The garnish further includes a rib and a flange portion. The rib is located along the inside surface of the cover at the first end. Opposite the rib, the flange portion extends generally orthogonally from the first end of the cover. The rib and flange portion help to provide structural support between the hinge arm, hinge garnish, and trunk lid garnish which achieves an improved fitting appearance between all parts.
[0004] When the garnish is installed onto the hinge arm connecting the vehicle to the trunk lid, the garnish is secured by being sandwiched, at least in part, between the hinge arm and a trunk lid garnish covering a portion of the trunk lid. The rib projects from the cover to contact the hinge arm, thus utilizing the rigid hinge arm as a structural datum, and the flange portion extends to contact the trunk lid garnish which serves as a rigid planar support for the flexible trunk lid garnish, thereby helping to maintain a good fitting appearance between the hinge garnish and the trunk lid garnish.
[0005] Other features and advantages of the present invention will become apparent from the following detailed description with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] To complement this description and in order to aid in a better understanding of the invention's characteristics, a set of illustrative and non-limiting drawings is included as follows:
[0007] FIG. 1 shows a perspective view of a rear end of a vehicle having an open trunk lid with hinge arms covered by hinge arm garnishes;
[0008] FIG. 2 shows a perspective view of a portion of the hinge arm garnish nearest the trunk lid;
[0009] FIG. 3 shows a perspective view of a first end of the garnish;
[0010] FIG. 4 shows a perspective view of the inside surface of the first end of the garnish; and
[0011] FIG. 5 shows a cross sectional view of the first end of the garnish installed onto the hinge arm.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] With reference now to FIG. 1 , a garnish 10 of the present invention designed for a hinge arm 15 (not shown in FIG. 1 because it is disposed under the garnish 10 ) connecting a trunk lid 20 to a vehicle 25 is shown. The garnish 10 includes a cover 30 with an inside surface 35 , an outside surface 40 , a first end 45 and a second end 50 . The garnish 10 also includes a rib 55 , and a flange portion 60 , shown in FIGS. 3 and 4 .
[0013] The cover 30 has a curved profile from the first end 45 to the second end 50 . The curved profile is designed to minor that of the hinge arm 15 to be covered by the garnish 10 . The first end 45 of the cover 30 is designed to be located at an end of the hinge arm 15 that attaches to the trunk lid 20 , and the second end 50 is designed to be located at an end of the hinge arm 15 closer to the interior of the trunk 65 of the vehicle 25 .
[0014] With reference now to FIG. 4 , the rib 55 is disposed on the inside surface 35 of the first end 45 of the cover 30 . The rib 55 is rectangular in shape, and includes rounded corners. The rib 55 is designed so as to contact the hinge arm 15 when the garnish 10 is installed onto the vehicle 25 .
[0015] As shown in FIG. 3 , the flange portion 60 extends generally orthogonally from the first end 45 of the cover 30 . The flange portion 60 extends from the outside surface 40 of the cover 30 . In the preferred embodiment, the outside surface 40 of the cover 30 faces three directions and the flange portion 60 extends away from the cover 30 so as to include all three directions. A transition area 70 between the cover 30 and the flange portion 60 includes a curvature or radius on the inside surface 35 and the outside surface 40 of the cover 30 . The curved transition area 70 produces a more aesthetically pleasing part, and aids in installation by reducing the number of sharp corners. The orthogonally extending flange portion 60 covers the attachment of the hinge arm 15 to the trunk lid 20 and provides a contact surface to aid in securing the garnish 10 , as discussed below.
[0016] Again with reference to FIG. 4 , the rib 55 extends generally orthogonally from the inside surface 35 of the cover 30 . The generally orthogonal orientation of the rib 55 can be compared to a line that is tangent to the cover 30 where the rib 55 is located. Because the cover 30 mirrors the hinge arm 15 , the rib 55 should be generally orthogonal to the hinge arm 15 when the garnish 10 is installed, thereby applying pressure to the rib 55 in a direction that is parallel to the orientation of the rib 55 .
[0017] The rib 55 is reinforced with one or more support structures 75 . The support structure(s) 75 span from the rib 55 to the inside surface 35 of the cover 30 . The support structure(s) 75 are generally triangular in shape and extend generally perpendicular from the cover 30 and generally perpendicular from the rib 55 . The preferred embodiment includes three support structures 75 . One support structure 75 a is located on one side of the rib 55 near the middle, and the other two support structures 75 b are located on the opposite side of the rib 55 and spaced apart from the middle.
[0018] With reference now to FIGS. 1-4 , the cover 30 includes a center portion 80 and two side portions 85 . The side portions 85 extend generally perpendicular from center portion 80 . The center portion 80 and the side portions 85 form a general U-shape with a flat bottom when viewed in cross section. Similar to the cover 30 discussed above, the generally U-shape formed by the center portion 80 and the side portions 85 follows a profile running from the first end 45 to the second end 50 of the cover 30 that is similar to the profile of the hinge arm 15 .
[0019] In one embodiment, the rib 55 extends from the center portion 80 and is disposed between the two side portions 85 . The rib 55 is orthogonal to the center portion 80 and perpendicular to the side portions 85 . A space exists between the rib 55 and the side portions 85 .
[0020] The garnish 10 is installed over the hinge arm 15 . The garnish 10 extends along the length of the hinge arm 15 at least as far as would be visible to a user opening or closing the trunk 20 . The flange portion 60 of the garnish 10 is disposed near the trunk lid 20 . A trunk lid garnish 90 covers the inside surface of the trunk lid 20 , and includes an opening 95 for the hinge arm 15 and hinge arm garnish 10 . The trunk lid garnish 90 is attached to the trunk lid 20 and helps to secure the hinge arm garnish 10 . As shown in FIG. 5 the garnish 10 is sandwiched by the trunk lid garnish 90 contacting the flange portion 60 on one side of the garnish 10 , and by the hinge arm 15 contacting the rib 55 on the other side of the garnish 10 . The opposing force generated by these two contact points secures, at least in part, the garnish 10 relative to the hinge arm 15 and trunk lid garnish 90 .
[0021] When installed, the garnish 10 covers the hinge arm 15 and the attachment of the hinge arm 15 to the trunk lid 20 . The U-shape cross section covers three sides of the hinge arm 15 , essentially hiding the hinge arm 15 from view of a user opening or closing the trunk. The flange portion 60 extends to cover the attachment of the hinge arm 15 to the trunk lid 20 by extending underneath the trunk lid garnish 90 thereby hiding from view any components that would be visible though the opening 95 in the trunk lid garnish 90 designed to receive the hinge arm 15 and hinge arm garnish 10 .
[0022] The garnish 10 can be integrally molded from plastic as a single unit using injection molding. Based on the above teachings, other materials and manufacturing methods known to those skilled in the art can be used to produce the garnish 10 .
[0023] Obviously, many modifications and variations of the present invention are possible in light of the above teachings and may be practiced otherwise then as specifically described while within the scope of the appended claims. | The present invention is a garnish that is specially designed to cover the hinge arm connecting a vehicle truck lid to the vehicle. The cover includes an inside surface, a first end and a second end. The cover further includes a rib and a flange portion. The rib is located along the inside surface of the cover at the first end. Opposite the rib, the flange portion extends generally orthogonally from the first end of the cover. The rib and flange portion help to secure the garnish and increase its effectiveness at covering other components of the vehicle. | 4 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a method of tuning an active safety system of a motor vehicle, notably an antilock braking system (ABS), an anti-skid system (ARS or TSC), a path control device (ESP), an overall motor vehicle chassis control system (VDM) or similar, and an active safety system obtained by said method and/or the motor vehicles equipped with such an active safety system.
[0002] As is known, the behaviour of the vehicles depends on the tyre grip of the wheels on the rolling surface. This behaviour is notably degraded when said tyre grip diminishes, for example on wet ground, on wet grass, on oil puddles, on snow or on black ice. Thus, the motor vehicle manufacturers have been urged to equip the vehicles with active safety devices or systems referred to in the art by their English abbreviations ABS, ESP, ASR, ACC, VDM, at least partially compensating for the degradation of the behaviour of the vehicle rolling on a surface with low or very low tyre grip. Unfortunately, developing these systems demands the availability of a rolling surface with the desired tyre grip. Tests on tracks made of polytetrafluoroethylene (PTFE), sprinkled with water, may give a first approximation of the behaviour of the vehicle, but do not allow for fine adjustment. Thus, extremely costly tests are needed on snow and/or on ice.
SUMMARY OF THE INVENTION
[0003] Consequently, one aim of the present invention is to offer a method of tuning effective active safety systems without having to use rolling surfaces with low tyre grip.
[0004] Another aim of the present invention is to offer a method of tuning active safety systems in an environment with temperate, that is to say above 0° C.
[0005] Another aim of the present invention is to offer a method of tuning effective active safety systems on non-uniform surfaces such as sheets of black ice or puddles of oil.
[0006] Another aim of the present invention is to offer active safety systems that are extremely effective on rolling surfaces with low tyre grip such as snow or black ice.
[0007] Another aim of the present invention is to offer vehicles equipped with such active safety systems.
[0008] These aims are achieved, according to the present invention, with a method of tuning active safety systems employing a vehicle comprising at least one wheel equipped with a coating with low tyre grip advantageously made of a plastic material with low friction coefficient, preferably of the polytetrafluoroethylene (PTFE) type or a mixture or an alloy of PTFE with other materials.
[0009] The main subject of the invention is a method of tuning an active safety system of a motor vehicle comprising steps consisting in:
[0010] a) storing parameters in storage means;
[0011] b) testing the behaviour of a reference vehicle with said parameters stored in said storage means with tyre grip values for the tyre treads of areas on a rolling surface less than 0.6;
[0012] c) modifying the stored parameters according to the behaviour of the vehicle until a desired vehicle behaviour is obtained, characterized in that it also comprises a step;
[0013] d) of equipping the vehicle with at least one area comprising a tyre tread that has a tyre grip less than 0.6 at a temperature above 0°.
[0014] Another subject of the invention is a method that is characterized in that the step d) comprises a step d 1 ) for fitting a ring made of a material with low friction coefficient around a tyre of an area and a step d 2 ) for mounting said wheel on said vehicle.
[0015] Another subject of the invention is a method characterized in that the ring is made of a material comprising PTFE.
[0016] Another subject of the invention is a method characterized in that it also comprises a step e) for writing the parameters retained on completion of the step c) into a permanent memory of a computer of an active safety system.
[0017] Another subject of the invention is a method characterized in that said parameters comprise threshold values of the regulator of said active safety system.
[0018] Another subject of the invention is a method characterized in that said parameters comprise gain values of the regulator of said active safety system.
[0019] Another subject of the invention is a method characterized in that it comprises a step b) with a tyre grip less than or equal to 0.1.
[0020] Another subject of the invention is a method characterized in that, in the step d), the vehicle is equipped with four wheels, each comprising a tyre tread that has a tyre grip less than 0.6.
[0021] Another subject of the invention is an active safety system characterized in that it comprises storage means in which are stored the parameters determined by the method.
[0022] Another subject of the invention is a motor vehicle characterized in that it comprises an active safety system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The present invention will be better understood from the following description and the appended figures given as nonlimiting examples and in which:
[0024] FIG. 1 is a perspective view of a coating with low tyre grip likely to cover a wheel of a motor vehicle when tuning the method according to the present invention;
[0025] FIG. 2 is a perspective view of a wheel of a motor vehicle equipped with the coating of FIG. 1 ;
[0026] FIG. 3 is a plan schematic view of the preferred exemplary embodiment of the coating employed by the method according to the present invention;
[0027] FIG. 4 is a flow diagram illustrating the implementation of the method according to the present invention;
[0028] FIG. 5 is a flow diagram detailing an important step of the method illustrated in FIG. 4 ;
[0029] FIG. 6 is a flow diagram illustrating the preferred mode of implementation of the method according to the invention.
DETAILED DESCRIPTION
[0030] In FIGS. 1 to 6 , the same references are used to denote the same elements.
[0031] FIG. 1 shows, in perspective, a ring made of a material with low friction coefficient, such as, advantageously, PTFE or a PTFE-based material, comprising a radially internal surface 3 intended to receive the tyre tread of a tyre 5 ( FIG. 2 ) and a radially external surface 7 forming tyre tread during the tuning method according to the present invention. The ring 1 advantageously covers the entire width of the tyre 5 and may include, as illustrated in FIG. 3 , rounded portions 9 . The external surface 7 is advantageously smooth. The internal surface 3 is either smooth, as illustrated, or equipped with protuberances advantageously of a shape complementing the profiles of the tyre to be equipped, so as to improve the anchoring of the ring 1 on the tyre 5 . The thickness of the ring 7 (that is to say the distance between the radially internal surface and the radially external surface according to a diameter of the ring 1 ) is sufficient to, on the one hand, confer a traction resistance that is sufficient to allow mounting around a deflated tyre then secure attachment by inflating the tyre, and, on the other hand, to withstand wear for a reasonable time corresponding to all or some of the tuning operations to be carried out. This thickness is, for example, between 1 mm and 10 cm, preferably between 3 mm and 3 cm, and even more preferably between 5 mm and 1.5 cm, for example equal to 8 mm, 10 mm or 12 mm.
[0032] Advantageously, a set of calibrated rings 1 is produced, whose tyre grip, on a reference surface, for example dry asphalt, asphalt sprinkled with water or similar, corresponds to a longitudinal tyre grip ranging from 0.5 to 0.1, in combination with transversal tyre grips ranging from 0.5 to 0.1.
[0033] Advantageously, the rings 1 are provided with markings and/or automatic identification systems such as bar codes or RFID markings to facilitate the traceability of the tests carried out during the tuning procedure according to the present invention. This marking is used to identify the ring and its characteristics.
[0034] To perform tests, the tyre 5 of a standard wheel is deflated so as to facilitate the fitting of the ring around the tyre 5 (internal surface 3 of the ring 1 facing the tyre tread of the tyre 5 ) and, once the ring 1 is fitted around the tyre 5 , the tyre is reinflated to a pressure allowing an angular secure fixing between the tyre 5 and the ring 1 . Typically, tyres are reinflated to the usual pressures or to slightly higher pressures, typically between 10 5 Pa and 10 6 Pa, preferably between 2 10 5 Pa and 3.5 10 5 Pa.
[0035] Although the wheel illustrated in FIG. 2 corresponds to the preferred exemplary embodiment, it is obvious that the use of other wheels that have a rolling surface with a tyre grip on a standard rolling surface such as asphalt of between 0.5 and 0.1 will not depart from the context of the present invention. For example, the production of tyres made of PTFE, of tyres whose tyre tread is directly made of PTFE or of solid tyres with a tyre tread made of PTFE or of a similar material will not represent a departure from the context of the present invention.
[0036] FIG. 4 shows a flow diagram illustrating the method according to the present invention. In 11 , a startup phase is carried out corresponding to the configuration 13 of the tuning equipment. The phase 11 and the configuration 13 are similar to the startup phases of known-type methods.
[0037] The next step is 15 . In 15 , the active safety systems are tuned on high tyre grip, that is to say on a tyre grip greater than 0.6. For example, as illustrated in 17 , the thresholds and gains of the regulators of the active safety systems to be tuned, such as ABS, TSC, ESC, are adjusted by using conventional tyres on a conventional surface. The step 15 is similar to the high tyre grip tuning steps of known type.
[0038] The next step is 19 . In 19 , at least one wheel of the vehicle for which the active safety system is being tuned is equipped with a ring 1 . Typically, all four wheels of the vehicle are equipped with rings 1 for the adjustment of thresholds and gains of regulators, notably of ABS, TSC, ESC, by simulating the behaviour of the vehicle on snow and on ice by low tyre grip of the external surface 7 of the rings 1 . In a first exemplary embodiment, the vehicle is equipped with a braking system provided with a standard brake fluid. In a variant, this brake fluid may be replaced with a fluid having characteristics similar to those of the brake fluid at low temperature, such as, for example, an oil with high viscosity. Thus, the presence of snow or black ice and cold are simultaneously simulated.
[0039] The method according to the present invention makes it possible to simulate rare events that are difficult to produce during tests of known type such as, for example, a tyre grip on the front wheel trains that is different from that of the rear wheel trains of the vehicle corresponding, for example, to a sheet of black ice, a tyre grip that is different on the left side of the vehicle from that on the right side of the vehicle corresponding, for example, to a start on a road with two wheels already positioned in snow whereas the other two wheels of the vehicle are still on the road or other surface. Thus, advantageously, the method according to the present invention comprises a step 19 with four wheels equipped with rings 1 then the equipping of the two in-line wheels with the rings 1 on one side and/or the other of the vehicle, equipping of the two diagonal wheels with rings 1 and the equipping of a front wheel with a ring 1 notably for traction tests for TSC systems and the equipping of a rear wheel for the creation of instability for the type of tests encountered on sheets of black ice.
[0040] The tests are advantageously repeated with various friction coefficients of the ring 1 and/or with sprinkling of the test track so as to reproduce the behaviour of the vehicle for various tyre grips between 0.5 and 0.1.
[0041] The next step is 23 . The step 23 covers a final integration on high tyre grip and final validation with, as illustrated in 25 , final adjustments of the regulators of the safety system.
[0042] FIG. 5 shows the step 19 of FIG. 4 in more detail. In 27 , the tyre grip to be tested, for example 0.5, 0.3 or 0.1, is determined. The next step is 29 . In the phase 29 , the vehicle is equipped accordingly, that is to say, according to the test or tests to be carried out, the vehicles are equipped with one, two, three or four wheels comprising rings whose tyre grip on the test track corresponds to that determined in 27 .
[0043] The next step is 31 . In 31 , the applicator in charge of the tests enters parameters of the active safety system into the test system. These parameters correspond in particular to the threshold and gain of the regulators. The initial values correspond, for example, to the values retained for a similar vehicle previously tuned.
[0044] The next step is 33 . In 33 , the applicator drives the vehicles in normal conditions and extreme conditions so as to check the correct behaviour of the vehicle equipped with the active safety system according to the present invention. If the system behaves in a manner that conforms to the specifications with regard to safety and/or comfort, the method goes on to step 35 . Otherwise, the method returns to 31 . In 31 , the applicator modifies the parameters, notably the thresholds and gains of the regulators, according to the behaviour of the vehicle during the preceding test or tests 33 .
[0045] If yes, the step 19 is terminated at 37 . In 35 , a check is carried out to ensure that all the configurations, notably all the tyre grips, have been tested, otherwise the method returns to 27 . In 27 , the tests are begun for another configuration, for example, another tyre grip or another arrangement of the wheels equipped with rings 1 .
[0046] In the example of FIG. 4 , the step 15 is separate from the step 19 by analogy with the known-type tuning method. However, it may prove advantageous, as illustrated in FIG. 6 , to combine the steps 15 and 19 in a single step 19 ′, during which the tuning of all the tyre grips is performed with, as illustrated in 21 ′, the adjustment of all the parameters, notably the threshold and gain of the regulators. The tests are thus accelerated according to the availabilities of the applicators and of the vehicle prototypes to be tuned and of the test rigs.
[0047] The parameters determined in 31 / 19 and validated in 23 , notably the regulator threshold and gain adjustment, are stored in the permanent program memory of the computer of the active safety system intended for the production-line vehicles whose assembly is handled by the motor vehicle manufacturer. A permanent memory of the read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM) and/or flash EEPROM type is used.
[0048] The present invention applies notably to the motor vehicle industry.
[0049] The present invention applies mainly to the active safety system industry.
REFERENCES
[0050] Ring: 1
[0051] Internal surface: 3
[0052] Tyre: 5
[0053] External surface: 7
[0054] Rounded edge 9
[0055] Startup phase: 11
[0056] Configuration: 13
[0057] Tuning high tyre grip: 15
[0058] Adjustment of regulators: 17
[0059] Tuning low tyre grip: 19
[0060] Adjustment of regulators: 21
[0061] Integration and validation: 23
[0062] Adjustment of regulators: 25
[0063] Choice of tyre grip: 27
[0064] Vehicle equipment: 29
[0065] Choice and/or storage of parameters 31
[0066] Checking conformity of 33
[0067] vehicle behaviour with
[0068] desired behaviour
[0069] Checking exhaustiveness of tests 35
[0070] End 37 | The present invention relates to a method of tuning an active safety system of a motor vehicle, notably an antilock braking system (ABS), an anti-skid system (ARS or TSC), a path control device (ESP), an overall motor vehicle chassis control system (VDM) or similar, and an active safety system obtained by said method and/or the motor vehicles equipped with such an active safety system.
The subject of the present invention is a method of tuning active safety systems employing a vehicle comprising at least one wheel equipped with a coating ( 1 ) with low tyre grip advantageously made of a plastic material with low friction coefficient, preferably of the polytetrafluoroethylene (PTFE) type or a mixture or an alloy of PTFE with other materials.
The present invention applies notably to the motor vehicle industry.
The present invention applies mainly to the active safety system industry. | 1 |
BACKGROUND OF THE INVENTION
The present invention relates to a new and improved construction of measurement apparatus for determining the degree of filling of a casting mold -- also conveniently simply referred to as a mold --, having mold halves or parts which are supported against one another, against the action of a molding mass or material filled under pressure into a molding compartment or cavity of the mold, by means of a displacement device embodying a closure device comprising a closure cylinder and a closure piston.
It is already known to the art in the case of injection molding machines for processing plastic materials which can be plasticized, to automatically regulate parameters influencing the degree of filling of the mold, such as for instance the injection pressure, the after-pressure, the dosing volume or the setting time of the injected material, as a function of the relative movement occurring between the two mold halves which is in the sense of opening the mold due to the action of the pressure of the injected mass of material during the injection molding operation. It has already been proposed to arrange measurement or measuring devices at the mold, which devices sense the changes in shape or position of the mold brought about by the pressure of the injection molding material in the form of a signal value or amplitude. Measuring devices of this type are associated with a number of different drawbacks. What should be readily apparent is especially the disadvantage that each time the mold must be replaced it is equally necessary to exchange the measurement device together with the mold, and thus, sensitive components of such measurement device are exposed to the danger of damage. There can be however also provided for each mold a separate measurement device, but such is associated with considerable additional costs.
Furthermore, it has been found in the case of measurement devices which are arranged at the mold the measurement operation is exposed to disturbance factors which falsify the measurement result and lead to disturbances in the regulating function. Thus, for instance, the measurement operation can be influenced by the thermal energy transmitted from the heated mold to the measurement device.
Disturbance factors also have been then ascertained when the measurement device is arranged at one of both mold clamping or mounting plates because the bending-through of such mold mounting plates -- and which bending-through arises under the action of the closing pressure of the mold -- influences the measurement result.
SUMMARY OF THE INVENTION
Hence, it is a primary object of the present invention to provide a new and improved construction of measurement apparatus for determining the degree of filling of a mold which is not associated with the aforementioned drawbacks and limitations of the prior art proposals.
Further, in consideration of the aforementioned drawbacks, it is an additional noteworthy objective of the present invention to carry out the measurements for determining the degree of filling of the mold, independently of the exchange of the mold, by means of a measurement device which continuously remains at the molding machine, leding to the beneficial result that the disturbance factors which arise at the region of the mold do not effect the measurement results.
Yet a further object of the present invention aims at the provision of a new and improved construction of measurement apparatus for determining the degree of filling of a mold, said measurement apparatus being structured and oriented such that it need not be replaced each time that the mold is exchanged, rather remains affixed to the molding machine, and disposed at a location where it is not exposed to disturbances or other factors which could produce spurious measurement results.
Now in order to implement these and still further objects of the invention, which will become more readily apparent as the description proceeds, the measurement apparatus of this development is manifested by the features that there is provided a measurement value transmitter responsive to the relative position of the closure piston which is movable to a limited degree with respect to the closure cylinder, wherein a first transmitter component or part of the measurement value transmitter is connected to the closure cylinder and a second transmitter component or part is connected with the closure piston. According to a preferred arrangement of the measurement value transmitter, a first transmitter component is secured to a cylinder flange and a second transmitter component is coupled with a piston neck or rod of the closure piston, this coupling advantageously occurring in a force-locking manner, in other words for instance, frictionally or drag connected.
BRIEF DESCRIPTION OF THE DRAWINGS
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 drawings on the basis of which the invention will be explained in conjunction with four exemplary embodiments illustrated in the drawings and wherein:
FIG. 1 illustrates a contactless measurement feeler shown in three different arrangements at a closure unit or device of an injection molding machine illustrated in side view;
FIG. 2 is an enlarged view showing details of one of the measurement feeler-arrangements portrayed in FIG. 1 and
FIG. 3 is a view similar to the showing of FIG. 2 of a measurement device employing wire strain gauges or the like.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Describing now the drawings, it is to be first of all understood that only enough of the details of the molding machine, with which there is employed the measurement apparatus of this development for determining the degree of filling of a mold thereof, has been shown in order to enable those skilled in the art to readily understand the basic concepts and underlying principles of the present invention. Hence, there is shown in FIG. 1 an injection molding machine, generally indicated by reference character 100, wherein at a mold closure unit thereof for closing the mold 11, 12 a stationary mold mounting plate 3 is anchored at the columns 1 by means of nut members 2 or equivalent structure. The mold mounting or clamping plate 3 is appropriately interrupted at location 3a to form a pour opening 4 for the introduction of a not particularly illustrated but conventional injection cylinder, as is well known in this particular field of technology. With the aid of for instance identical nut members 2 or equivalent structure a closure cylinder 6 is secured by means of its cylinder flange or flange means 5 at the other end of the columns 1.
A closure piston 9 is mounted to be axially displaceable within the closure cylinder 6. This closure piston 9 can be conventionally impinged by a suitable fluid medium, typically an hydraulic medium such as oil. Closure piston 9 will be seen to comprise for example a piston head 7 and a piston neck or rod 8 or the like. The closure piston 9 and a movable mold mounting plate 10 form as a rigid unit the movable portion of a displacement device which also embodies the closure cylinder 6. Hence, the displacement device may be considered to comprise the closure cylinder 6 and the therein mounted closure piston 9 together with the movable mold mounting plate 10. The mold mounting plates 10 and 3 each carry one respective mold part or half 11 and 12 these mold halves 11 and 12, when the mold 11, 12 is closed, enclosing a mold compartment or cavity 14 at the region of a mold separation plane 13.
For the injection molding machine portrayed in FIG. 1 there have been shown three different arrangements of measurement value transmitters A, B, and C. Initially, with respect to FIG. 2 there will be considered the measurement value transmitter A which comprises a transmitter component or part 15 which is connected by means of a permanent magnet 16 with the cylinder flange 5 of the closure cylinder 6. This transmitter component 15 which is provided with a recess 17 and a bore 18 carries at its underside two seals 19. A second transmitter component or part 20 is inserted with lateral play into the recess 17 of the first transmitter component 15 and adheres by means of a permanent magnet 21 at the piston neck 8, a sliding sole or base 22 formed of a material having good sliding or antifriction properties being interposed between the permanent magnet 21 and the piston neck 8. The transmitter component 20 which is assembled together from two halves 20a by means of screws 23 or other suitable fastening expedients houses therein an inductive measurement feeler 24 composed of the measurement coils 24a. The measurement feeler 24 is a conventional commercially available measurement feeler and both of the measurement coils 24a form one-half of a Wheatstone bridge. These measurement coils 24a are augmented by standard resistors, which have not been particularly illustrated, into a full measuring bridge at a not particularly illustrated measurement amplifier which is connected via a measurement line or conductor 25 with the measurement feeler 24. The measurement coils 24a are advantageously flush at their end faces 24b with the side walls 20b of the transmitter component 20, as shown. The pick-up of the signal representing the measurement value occurs in such a manner that the apparent resistance or image impedance of the measurement coils 24a is influenced by changing two measurement gaps or spaces 26 and 27 formed by the end faces 24b of the measurement coils 24a and the side walls 17a of the recess 17, and thus there occurs a relatively small detuning of the balanced bridge circuit. At the output of the bridge circuit there appears a measurement voltage which is proportional to the small bridge detuning or imbalance which can be linearly amplified a number of times in a standard measurement amplifier and rectified in such a manner that a voltage serving as a regulation magnitude can be delivered to a conventional indicating- or regulation device. To simplify the illustration of the drawings the resistors or equivalent structure completing the Wheatstone bridge, the measurement amplifier, the indicator- or regulation device have not been particularly shown since the same constitute standard components and the details thereof are not considered important to the understanding of the principles of the invention by those skilled in the art beyond what has been explained above.
Prior to the injection molding operation the mold half 11 is brought into contact at the mold separation plane 13 with the mold half 12 due to the displacement movement or stroke of the closure piston 9 and is held in the mold closure or closed position with a predetermined, constant holding force. The force of the magnet 21 is dimensioned such that with the displacement of the closure piston 9 the piston neck 8 thereof initially displaces the transmitter component 20 until it impacts against the right-hand side of the transmitter component 15 and thereafter upon nullifying the measurement gap 27 allows such transmitter component 20 to remain at rest.
During the subsequent injection molding operation in the terminal phase of filling of the injection mold compartment 14 there is effective a pressure of the injected mass of material which counteracts the constant holding force of the closure piston 9, and accordingly, has the tendency of displacing the closure piston 9 in the opposite direction. This return displacement or stroke must be only of such a magnitude that at the mold separation plane 13 there is not formed any or only a very small mold gap in order to prevent an impermissibly large formation of flash or the like at the finished molded article. With this very small return stroke or displacement of the closure piston 9 which occurs relative to the closure cylinder 6 there is also displaced the transmitter component 20 which frictionally adheres by the magnetic force at the piston neck 6. As a result, the measurement gap 27 which was previously annihilated during the closing movement of the closure piston 9 is again formed and the measurement gap 26 located at the left-hand side of the transmitter component 20 again becomes smaller, and specifically, both changes in the dimensions of the measurement gaps or spaces 26, 27 take place exactly as a function of the pressure of the mass prevailing in the molding compartment 14 and acting against the constant holding force of the closure piston 9. With the so-to-speak mirror-image arrangement of both measurement coils 24a with respect to the transmitter component 15 both measurement coils 24a participate in the formation of the measurement value. Each displacement of the transmitter component or part 20 brings about an equal size, however opposing change of the measurement gaps or spaces 26 and 27. As a result, the inductances of the coils 24a are opposingly altered and thus the measurement sensitivity is additively increased. With this pick-up of the measurement value of the measurement value transmitter A it is possible by means of a suitable regulation device to regulate the control or regulation magnitudes which influence the degree of filling of the mold, such as for instance the injection pressure, the after-pressure, the dosing volume or the setting time of the injected plastic mass.
A different arrangement of measurement value transmitter B has been shown in FIG. 1 wherein the same is located, for instance, at the extreme left-hand bottom portion or end of the closure cylinder 6. With this constructional embodiment of measurement value transmitter B a rod 28 anchored at the piston head 7 is guided through the base or bottom portion of the closure cylinder 6 and extends with its free end 28a through a housing-like transmitter component or part 29, in the side walls of which there are embedded two measurement coils 30. Within the transmitter component 29 there is provided a second transmitter component or part 32 which is suitably force-lockingly or frictionally coupled at the rod 28 by means of for instance a magnet 31. Owing to the lateral play of the second transmitter component 32 there are located in front of both measurement coils 30 two measurement gaps or spaces 33 and 34. In contrast to the previously described measurement value transmitter A, in the case of the measurement value transmitter B the transmitter component 29 carrying the measurement coils 30 is stationary and the transmitter component 32 forming the armature is movable. However, functionally considered in both exemplary embodiments there is no difference inasmuch as also here the return displacement or stroke of the closure piston 9 opposingly varies the measurement gaps or spaces 33 and 34 and thus two measurement coils 30 participate in the formation of the measurement value.
As a further exemplary embodiment of the invention there is illustrated in FIG. 1 a measurement value transmitter C in which an inductive measurement feeler 35 is mounted in such a manner in the cylinder flange 5 that such feeler when the mold is closed, forms together with the piston head 7 a measurement gap or space 36. The measurement feeler 35 thus forms the transmitter component or part, secured at the closure cylinder and the piston head 7 forms the second transmitter component connected with the closure piston. In the case of the measurement feeler 35 only one measurement coil detects the changes of the measurement gap or space 36, whereas a reference gap of a second passive coil remains constant. Since in this case only one branch of the bridge of the half-bridge is detuned or placed into imbalance, the effect upon the total measurement bridge circuit and thus the measurement sensitivity is less than with the measurement value transmitters A and B previously discussed above.
According to a still further embodiment of measurement value transmitter D as shown in FIG. 3 a transmitter component or part 38 is connected by means of screws 37 or the like at the cylinder flange 5 and which possesses an opening 39 disposed over the piston neck or rod 8. By means of a screw 40 or equivalent structure there is fixedly clamped a leaf or blade spring 42 between the transmitter component 38 and a clamping plate 41, this leaf spring 42 being bent into a loop 43 and is anchored at its other end between two pins 44 at a second transmitter component or part 45. The transmitter component 45 which is mounted in the opening 39 with lateral play between two stops or impact members 46 adheres by means of a magnet 47 or the like at the piston neck or rod 8. At the leaf spring 42 there are mounted two wire strain gauges 48 or equivalent structure which are connected via the lines or conductors 49 with a connection location or terminal 50.
With the movement of the closure piston 9 into the mold closure piston the transmitter component 45 frictionally adhering to the piston neck 8 is displaceably entrained until reaching the right-hand located stop or impact member 46. The leaf spring 42 thus experiences a small bending or deflection as a result of which there occurs between both strain gauges 48 a length- or resistance difference. With the return displacement or stroke of the closure piston 9 which occurs during the injection molding operation the transmitter component 45 is shifted towards the left as a function of the pressure of the mass which prevails in the mold compartment or cavity 14. The resistance difference of both wie strain gauges 48 which previously arose due to bending of the blade or leaf spring 42 changes in accordance with the return displacement of the transmitter component 45 and the restoring or return bending movement of the leaf spring 42. The measurement value recorded or sensed by the wire strain gauges 48 and produced due to the relative movement between the transmitter component 38 and the transmitter component 45 is delivered to a conventional measurement amplifier where the wire strain gauges likewise can be connected into a Wheatstone bridge. The loop 43 has the function of compensating the distance changes, occurring during displacement of the transmitter component 45, between the clamping locations of the leaf or blade spring 42.
All of the exemplary embodiments have common therewith the feature that the measurement value transmitter is arranged externally of the region of the mold and its neighboring components. The measurement value transmitter thus can always remain in the machine independently of any exchange or replacement operation which has to be carried out at the mold and the measurements are not exposed to disturbing influences or factors emanating from the mold.
The pressure of the mass in the mold, i.e. the degree of filling is then most reliably determinable i.e. regulatable if the relative movement between the closure piston and the closure cylinder can be measured without any foreign disturbances, for instance bending of parts of the closure device. This is especially then the case when the measurement value transmitter is arranged directly at the location where the relative movement between the closure piston and the closure cylinder directly occurs. In this regard it is advantageous to arrange a transmitter component at the cylinder flange and a second transmitter component of the measurement value transmitter at the piston neck or rod or the like.
The measurement value transmitter, during each measurement, automatically selects a basic or starting position when a transmitter component of the measurement value transmitter is coupled in the manner of a drag connection in a limited range of movement with the closure piston in a force-locking or frictionally connected manner and loses the force-locking or frictional-connection with the closure piston by impacting at a second transmitter component. The measurement apparatus of this development is also usable in the case of hydraulic-mechanical closure devices, for instance in the case of combinations employing toggle lever-systems or the like.
While there are shown and described present preferred embodiments of the invention, it is to be distinctly understood that the invention is not limited thereto, but may be otherwise variously embodied and practiced within the scope of the following claims.
Accordingly, | A measurement apparatus for use with a molding machine comprising an electrical measurement value transmitter responsive to distance variations for determining the degree of filling of a casting mold, the mold parts of which are supported against one another in the closed position of the mold by means of at least one fluid-operated, for instance, hydraulic displacement device incorporating a closure cylinder and closure piston. One transmitter component of the electrical measurement value transmitter is operatively coupled with the closure cylinder and a second transmitter component of the measurement value transmitter is operatively coupled with the closure piston. | 1 |
This application is a continuation of Ser. No. 07/757,549, filed Sep. 11, 1991, now abandoned.
BACKGROUND OF THE INVENTION
This invention relates to mat forming apparatus or generally to material handling apparatus.
There are various applications where various mat-forming materials, such as natural and man-made fibers, particles, granules, filaments, slivers, strands, flakes, and the like, are processed to form a mat which is then further processed to arrive at a desired product. Such products can be reconstituted fiberboard, reinforced plastics, other composite articles, or the like. Various arrangements have been proposed for building such mats, for example gravity feed of the materials into a suitable mold, die, or other holding device, and arrangements which add a vibratory mechanism to the gravity feed. Some of the problems encountered in such prior art arrangements are the materials are either entangled at the start or become entangled in the process, such that they are delivered to the die in clumps. Also, they may become undesirably stratified due to differences in specific gravity, size and geometry of different materials. In addition, they may have a moisture content which is too high and, therefore, must be separately dried before further processing.
By way of further explanation, if delivered in clumps, or undesirably stratified, the uniformity and structural characteristics of the final product is affected. As a specific prior art problem, mats can be processed to composite articles through a compaction step wherein the fibers, with suitable binders, are compressed under heat and pressure. Too high a moisture content in the mats can result in steam being generated in the compaction step which can interfere with the compaction step and/or adversely affect the end product.
Among the objects of this invention is to provide a mat forming apparatus which provides generally uniform distribution of various materials or material mixes throughout the formed mat.
Another object of this invention is to provide a mat forming apparatus which inherently reduces the high moisture content of the materials being used to form the mat and which lends itself well to additional moisture removal.
A more general object of this invention is to provide apparatus capable of breaking up entangled materials and/or drying such materials as desired.
For the achievement of these and other objects, this invention proposes having a hollow material transporting member and drive means for producing a pressure differential across spaced portions of the transporting member so that materials are propelled from one spaced portion to the other within the hollow transporting member. Material directing means is also provided which communicates with the drive means for receiving materials from the hollow transporting means and, responsive to the drive means, is operative to direct received materials in a predetermined path. The hollow transporting member has a non-linear inner surface so that flow therethrough is turbulent causing materials being transported therein to experience turbulent flow in traveling from one spaced portion to the other. The apparatus may also include an arrangement associated with said material directing means for receiving the materials and confining received materials in a defined space.
Preferably, mat forming apparatus is made up of a blower and an elongated, hollow corrugated hose or tube, one end of which is open and the other end of which is attached to the inlet end of the blower so that the blower produces a pressure differential across the ends of the corrugated tube and the materials are propelled from the open end of the corrugated tube to the other end. A hollow, generally flexible or rigid, but swingable, tubular member has one end connected to the outlet of the blower and its other end freely movable and operative to direct received materials in a predetermined path or direction. The corrugated tube defines a non-linear inner surface so that flow in the corrugated tube is turbulent and causes materials to experience turbulent flow in being propelled from the open end to the blower. The arrangement also includes a frame associated with the hollow, flexible member for receiving and confining received materials in a defined space.
Preferably, the drive is a centrifugal blower and the materials are transported through the blower where they are further separated or mixed. Also, the apparatus includes a member having an interstitial construction such as a screen extending across the lower end of the frame to provide, at that point, a generally open construction permeable to air while preventing the passage therethrough of materials so that materials are accumulated in the frame. It is also contemplated that an exhaust arrangement will be associated with the frame to receive air passing through the frame, the exhaust mechanism itself being covered by the same type of member extending over the lower end of the frame and through which air must pass and against which the materials are directed. Means can also be included for withdrawing air from the interior of the exhaust mechanism to thereby enhance the overall flow of air through the apparatus while further augmenting the collection of the material in the formation of the mat.
Other objects and advantages will be pointed out in, or be apparent from, the following specification and claims as will obvious modifications of the embodiment shown in the drawings in which:
FIG. 1 is a perspective view of the preferred embodiment;
FIG. 2 is a sectional view taken along line 2--2 in FIG. 1;
FIG. 3 is a sectional view similar to FIG. 2 but showing the device in use, building up a mat;
FIG. 4 is a top view of FIG. 2 with parts broken away for clarity;
FIG. 5 is a sectional view similar to FIG. 3, showing an alternative embodiment;
FIG. 6 is a partial section of a compacted mat, prior to inverting;
FIG. 7 is a partial section of an inverted frame, with the mat deposited for transfer to a finishing station; and
FIG. 8 is a partial section of an alternative embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of this invention is illustrated in the drawings. Examples of materials which can be processed effectively with this arrangement are whiskers, filaments, wools, fibers, particles, granules, slivers, small strands or flakes, and the likes of alumina, asbestos, beryllium, boron, carbon (graphite), ceramics, glasses, kevlar, molybdenum, nylon, thermoplastic and thermosetting resins, rocks, rubbers and other elastomers, silicon carbide, steel, titanium, tungsten, other natural and man-made materials or mixtures of such materials or other similar materials. For convenience, the invention will be described with reference to wood fibers, it being appreciated that it does have other applications. Whatever material, or materials, that are being processed will come from a source S.
A blower 10 is connected to an elongated hose 12 and a second, elongated hose, or spout, 14. The blower is a centrifugal type blower and hose 12 is connected to the inlet of the blower through a suitable fitting 16. Similarly, spout 14 is connected to the outlet of the blower through a suitable fitting 18. With this arrangement, the blower provides a drive mechanism for drawing material through hose 12 and through the blower body, discharging that material through the spout 14. More particularly, the blower creates a pressure drop across the open or free end 20 of the hose 12 and the end of that hose connected to fitting 16 which causes material to flow through the hose to the blower.
Blower 10 is suitably connected to a bracket assembly 22 with the hoses 12 and 14 attached to and hanging loosely relative to the blower body.
A receiving assembly 24 is located beneath the blower 10, specifically beneath spout 14. This assembly includes a basic frame 26. The frame 26 is positioned beneath spout 14 and is made up of sidewalls 26a, b, c, and d. which define opposite vertical ends 28 and 30. Material drawn through hoses 12 and expelled through spout 14 is discharged into the frame 26. The spout 14, being flexible or rigid but swingable, can be manipulated to provide an even distribution of the material across the horizontal extent of the frame 26.
The simplest form of frame 26 is to have a closed bottom, such as a plate 27 attached to the underside of the frame as shown in FIG. 8, for the collection of fibers. To facilitate and enhance depositing the materials in an effective manner in frame 26, the lower end 30 of frame 26 is covered with a member having an interstitial type construction, i.e., a member having intersecting elements with spaces therebetween. The size of the openings depends on the size of the fibers being processed, the purpose being to allow the transporting airstream to pass freely while the fibers are captured by the frame. In the preferred embodiment, a screen 32 of suitable, predetermined mesh size is used. This screen is attached to the bottom end of the frame by brackets 34 and 36 attached to the frame.
Frame 26 and screen 32 are positioned above an exhaust box 38. The exhaust box is open to the screen 32 and forms a false bottom for frame 26. In this manner, the flow of material toward frame 26 is interrupted by screen 32 while the air, which provides the moving force for the fibers, can pass freely through the screen. More particularly, the air moves through screen 32 into the exhaust box 38 which also may be provided with a blower 40 connected in a conventional manner to the interior of box 38 and capable, when energized, to draw a vacuum in box 38. This vacuum enhances the flow of the materials into the frame 26 and further enhances the effective depositing of the materials above screen 32. A variable transformer 42 is connected to blower 40 so that the speed of the blower can be adjusted as desired. Similarly, a variable transformer (not shown) may be attached to blower 10 to control its speed.
It should be noted at this point, that hose 12 is corrugated and the interior surface 12b thereof, shown in a cut-away in FIG. 1, is interrupted and non-linear. By providing the interrupted surface on the interior of the hose 12, the air being drawn through that hose does not follow a linear path but is generally turbulent. As a result of this turbulence, materials drawn into the hose 12 through open end 20 also follow a non-linear, turbulent path. The advantages of this turbulence within the hose is that it tends to break up clumps of material into individual fibers or smaller clumps and, as will be discussed hereinafter, if a number of materials are used, tends to thoroughly mix those materials. Entanglement of materials may be caused by, for example, the natural tendency of certain materials to become entangled, attachment through adhesive coating where such coatings are used and/or static electricity. The individual fibers and/or smaller clumps when deposited in frame 26, make for a mat build-up which has a more uniform consistency.
In that same regard, the advantage of using a centrifugal blower is that the fibers are drawn through the interior of the blower, i.e., through the blower impeller blades 51, which will break up clumps of and/or mix the fibers further. The fibers, then in discrete form or in smaller clumps, are discharged through the spout 14 and into the frame. It will be noted that spout 14 is larger in diameter than hose 12. The advantage here is that a smaller diameter hose 12 enhances the turbulence within that hose which then provides thorough breakdown of the clumps and/or thorough mixing of the materials. The mixed and/or broken down materials, as they leave blower 10, are readily accommodated in the greater diameter spout 14 from which they are deposited in frame 26 in that separated, discrete form and are not given the opportunity to co-mingle and form clumps again.
It has been found that by breaking down clumps of the materials and by the mixing action in hose 12 due to the corrugated inner surface, and then propelling those particles into the frame 26 with the air from blower 10 as a driving or motive force, an even distribution in the materials in the frame 26 to provide a mat with consistent material characteristics is achieved. This is improved as compared to a strict gravity feed or even a gravity feed enhanced by a vibratory mechanism, in which arrangements the materials tend to stratify in the mat based on their specific gravity, size, and/or geometry. That is, with a straight gravity feed or even one used with a vibratory assembly, the higher specific gravity and finer materials will tend to accumulate toward the bottom of the mat, while the lesser specific gravity or bulky materials will tend to accumulate toward the top of the mat. Obviously, any clump of material is an undesirable feature as it produces an undue concentration in one area of the mat and, similarly, uneven distribution of materials is not desirable.
It is also desirable to have a second screen 44 extend across the opening 46 in exhaust box 38 at the outlet of frame 26 and beneath screen 32. This provides a better base against which material can accumulate while allowing free passage of air.
To complete the mat forming procedure, the mat is removed from the overall apparatus in the following manner. Optionally, a compactor 48 is placed on the upper surface of the formed mat and can be pressed down manually or through some automatic means (not shown), and optionally with the concurrent of vacuum suction in box 38 to remove air trapped in the mat. Once the desired compactness of the mat has been achieved, the frame 26 is removed from the apparatus. A plate 50, preferably of metal, is inserted between screens 32 and 44 before removal, plate 50 can be impervious to air or a stiff screen as desired.
After the compactor is removed, a second impervious plate 52 is placed over the top of the formed mat. The assembly consisting of frame 26 and, from top to bottom, plate 52, the formed mat, screen 32 and plate 50 is inverted. The frame 26 assists in retaining materials in the loose mat during the inversion and assists in reducing the sideway spread of dust materials during the post-mat forming cold and hot pressing operation. After removing the frame 26, plate 50 and screen 32, a formed mat is left on the second plate 52. The formed mat can then be taken to another station (not shown) for further processing. For example, where the materials are wood fibers and the final product is a reconstituted wood fiber product, the wood fiber, coated with the binder, either before or after collection in frame 26, is moved to a press arrangement wherein the final form and thickness of the wood fiber product is achieved under pressure and temperature. The temperature causes the binder to set in the final reconstituted wood fiber product. All of these subsequent steps are performed in a conventional manner.
An auxiliary frame extension 54 can be provided if it is desired to provide a mat with a greater depth than that which can be provided in frame 26.
Both frames 26 and 54 are suitably lined to prevent adherence of the materials to their inner walls, for example lined with plexiglas 29 or are treated with an antistatic coating.
An added advantage of this mat forming apparatus is that in transporting the materials through hose 12 and blower 10, the moisture content of wet fibers can be inherently greatly reduced. For example, in the case of wood fibers, it has been recognized that the moisture content can be reduced to as low as 50%. With the preferred embodiment, it is also possible to provide heated air or an auxiliary heating arrangement associated with hose 12 to achieve even further drying of the materials. That heater can be in the form as shown in FIG. 1 where a heater 58 is wrapped on coil 12 and energized from a suitable electrical source 60.
In the preferred embodiment, the hose 12 has a diameter of 11/4". However, larger diameters may be preferred when larger size materials are being used to form mats. Whereas the diameter of spout 14 is approximately 4", its size and shape can be modified to define the discharge materials in a predetermined path. In addition, spout 14 may be provided with a nozzle 62 which operates to further confine the discharge of the materials for better placement of those materials in the frame 26. The advantage, as stated above, is that materials are broken down in the hose 12 to discrete fibers or smaller clumps. This comes about due to the interrupted interior surface of the corrugated hose where the turbulence causes friction, impaction, rubbing and shearing action between the fibers and/or fibers otherwise clumped into a ball. In addition, where it is desired to mix several different materials which will go into the make-up of the mat, this same phenomena insures thorough mixing within the hose.
Another advantage is the fibers, throughout their transport to the mat, are generally confined and not exposed to the environment. This reduces the discharge into the area surrounding the apparatus of undesirable particles, dust, and like.
FIG. 5 illustrates an alternative embodiment. Here a battery of parallel, defined open spaces are assembled into a honeycomb plate 61 and is positioned beneath screen 44 on the exhaust box. With this plate 61, the positioning of fibers in the frame can be naturally and pneumatically guided by the preferential flow of air through the mat where less materials are deposited. This process assists in making mats with more uniform thickness if desired.
Although this invention has been illustrated and described in connection with particular embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. | Mat forming apparatus comprising, in combination, a hollow material transporting member, drive structure for producing a pressure differential across spaced portions of the transporting member so that material is propelled from one of the spaced portions to the other within the hollow transporting member, material directing structure communicating with the drive structure for receiving material from the hollow transporting structure and, responsive to the drive structure, operative to direct the received material in a predetermined path, the hollow transporting member having a non-linear inner surface so that flow in the hollow transporting member is turbulent causing the material being transported therein to experience turbulent flow in being propelled from one of the spaced portions to the other, and structure associated with the material directing structure for receiving the material and confining the received material in a defined space. | 3 |
This is a continuation of application Ser. No. 09/025,184, filed Feb. 18, 1998 now U.S. Pat. No. 6,202,526.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to data communication apparatus and method for effectively communicating image data.
2. Related Background Art
Conventionally, in image communication to transmit and receive image information between terminals, especially, when it aims to transmit the image information to a specified individual, a facsimile apparatus for transmitting and receiving the image information based on a dedicated protocol by using mainly a public line, a method for adding an image file to an electronic mail transmitted between computer terminals connected to a network, or the like has been utilized.
Further, although it does not aim to transmit the image information to the specified individual, a WWW (World Wide Web) system utilizing a computer communication network becomes noticeable since an internet has been popularized. Like an internet application such as the electronic mail or the like, such the WWW system is a client/server system based on a communication protocol called a TCP/IP (Transmission Control Protocol/Internet Protocol). Further, such the WWW system has been developed as an information retrieval/provision system which can be realized by communicating not only the image information but also data such as text data, voice data, animation data and the like handled in a computer, between a client application having a GUI (Graphical User Interface) called a WWW browser and a WWW server application.
However, in case of utilizing the image communication performed by the above conventional facsimile apparatus, a reception side can not confirm or know what kind of image was transmitted until the transmitted image is actually printed. For this reason, there has been a problem that, even if the transmitted image is unnecessary information for the reception side, an operator at the reception side can not previously confirm contents of such the information to cancel unnecessary reception. Further, the facsimile apparatus tends to be utilized in common by plural operators, there is a premise that the image is transmitted between the two facsimile apparatuses, and the image is transmitted based on one-sided intention of the operator at the transmitter-side facsimile apparatus. Therefore, there have been problems that it is not assured that the transmitted image certainly reaches the operator (individual) at an intended destination, and also there is some fear that contents of the transmitted image are seen by a person other than the operator at the destination. Furthermore, when the operator at the transmission side aims to cause the operator at the destination to confirm necessity or unnecessity of the transmitted image, there has been inconvenience that the operator at the transmitter side must utilize other means, e.g., a telephone or the like, for such confirmation.
On the other hand, in such the conventional method as the image file is added to the electronic mail transmitted between the computer terminals connected to the network, since the electronic mail essentially intended for the individual is utilized, it is possible to solve the above-described problem by securing certainty that the image is transmitted to the operator at the destination. However, like the case where the facsimile apparatus is used, if the communication is not completed, the operator on the reception side can not confirm the received image. Therefore, there has been a problem that, even if the transmitted information is unnecessary for the reception side, the operator on the reception side can not previously confirm it and thus can not previously avoid receiving it. Further, since the electronic mail essentially aims to transmit and receive text data, if such the high-resolution and high-quality image file as used in the printing is added to the electronic mail, the data of which amount is significantly large must be transmitted, thereby seriously loading an electronic mail server. Furthermore, in order to display such the image file on a display device of the reception terminal, there has been a problem that a display application software is necessary, and a large-capacity memory is also necessary, thereby seriously loading a CPU.
SUMMARY OF THE INVENTION
An object of the present invention is to provide data communication apparatus and method which solve or eliminate the above-described conventional problems.
An another object of the present invention is to provide data communication apparatus and method which can transmit image information to a destination without increasing a load to a mail server.
A still another object of the present invention is to provide image communication apparatus and method which can transmit image data on the basis of an instruction from a reception side.
A still another object of the present invention is to provide image communication apparatus and method which can switch a communication method according to communication contents.
The above and other objects, features, and advantages of the present invention will be apparent from the following detailed description and the appended claims in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram showing schematic structure of an image communication apparatus according to an embodiment of the present invention;
FIG. 2 is a view showing structure of an image communication system according to the embodiment of the present invention;
FIG. 3 is a flow chart showing a process for transmitting an electronic mail by an image communication apparatus a;
FIG. 4 is a flow chart showing a process performed on the electronic mail received by a terminal 24 at a transmission destination; and
FIG. 5 is a flow chart showing a process as to handling of image data by the image communication apparatus.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinafter, an embodiment of the present invention will be explained in detail with reference to the accompanying drawings.
FIG. 1 is a block diagram showing structure of an image communication apparatus according to the present embodiment.
In FIG. 1 , reference numeral 11 denotes a CPU (central processing unit) which controls each unit in the apparatus based on programs stored in a ROM (read-only memory). Reference numeral 12 denotes a display unit which performs various displaying. For example, the display unit 12 displays a state of the apparatus, a screen for urging an operator to perform various operations, and the like. Reference numeral 13 denotes a console unit by which the operator inputs instructions according to the displaying on the display unit 12 . The console unit 13 may comprise any input device such as a key input button, a pointing device (e.g., mouse), a touch panel or the like. Reference numeral 14 denotes a storage unit which stores data representing an input image or the like as a file. Reference numeral 15 denotes a communication control unit which controls connection of the apparatus to an external network.
An image input unit 18 and an image output unit 19 are connected to an image input/output control unit 17 and controlled according to instructions from the CPU 11 . An image conversion unit 16 converts image quality such as resolution or the like.
FIG. 2 is a view showing system structure of an image communication system to which the image communication apparatus according to the present embodiment is connected.
In FIG. 2 , reference numerals 21 and 22 respectively denote the image communication apparatuses shown in FIG. 1 . To simplify the explanation, it is assumed that the apparatus 21 is handled as an image communication apparatus a to be used for transmitting the data and the apparatus 22 is handled as an image communication apparatus b to be used for outputting a received image.
Each of the image communication apparatuses 21 and 22 has an image input/output function, a network communication function based on TCP/IP (Transmission Control Protocol/Internet Protocol) connection, a WWW (World Wide Web) server function, and an electronic mail transmission/reception function. Reference numeral 23 denotes a terminal which has been registered as a reply destination used when the image transmission is performed by the image communication apparatus a, and reference numeral 24 is a terminal which has been registered as an image transmission destination to which the image transmission is performed from the image communication apparatus a. These terminals are computer terminals (including CPU, memory, display unit and the like) which are connected to a network 26 . Further, reference numeral 25 denotes a mail server which provides electronic mail services to the terminals respectively connected to the network 26 . The apparatuses 21 and 22 and the terminals 23 and 24 are all connected to others by means of the network 26 . In this network 26 , if each apparatus or terminal is connected based on the TCP/IP, they may be connected to others through any line and/or any protocol conversion on the way.
Subsequently, the operation of the image communication apparatus of such the structure as described above in the present embodiment will be explained in detail with reference to flow charts shown in FIGS. 3 to 5 . These flow charts correspond to the control flows which are performed by the CPU 11 on the basis of program data stored in the memory of the apparatus.
FIG. 3 is the flow chart showing the operation that an operator of the image communication apparatus a performs the transmission operation and thus an electronic mail is transmitted to a transmission destination.
In FIG. 3 , in a step S 101 , it is initially recognized that an original to be transmitted to the image input unit 18 has been set by the operator. Then, in a step S 102 , it is further recognized the transmission destination and an instruction reply destination which have been set by the operator from the console unit 13 according to guidance displayed on the display unit 12 . At this time, it is possible to add previously prepared fixed-form text and/or comment by operator's input operation or preliminary setting. After confirming the input setting, the flow advances to a step S 103 .
In the step S 103 , it waits for key inputting to start the transmission. When it is instructed by the operator from the console unit 13 to start the transmission, the flow advances to a step S 104 . In the step S 104 , the image on the original to be transmitted which has been set from the image input unit 18 connected to the image input/output control unit 17 is read with a first image quality, the obtained image data is stored as an image file in the storage unit 14 , and then the flow advances to a step S 105 . In the step S 105 , the setting is changed to store the image file based on a second image quality of which resolution and color reproducibility are different from those of the first image quality. According to the changed setting, in a step S 106 , it is instructed to store the image file based on the second image quality. In this case, the original to be transmitted may be again read from the image input unit 18 to obtain the image data of the second image quality, or the image file of the second image quality may be formed by converting the data of the image file based on the first image quality with the image conversion unit 16 . In any case, the image files based on the two kinds of image qualities are formed from the identical image. The image files of the different image qualities formed and stored in such the manner as above are utilized as a display image (coarse image of which data amount is small) and a print image (high-quality image). The display image is displayed on a terminal on a receiver side and used to confirm the received image, and the print image is transferred as print data after the receiver side confirmed such the display image. It is possible to prepare the plural display images and the plural print images to enable providing them according to display capability and print capability of the terminal on the receiver side or the image communication apparatus used for the image outputting. Further, the display image and the print image can be appropriately converted by the image conversion unit 16 . By such the processes, when the image files of the respective image qualities are correlated with the information set in the step S 102 and then stored into the storage unit 14 , the flow advances to a step S 107 . In the step S 107 , locations of the display image files and the print image files formed and stored till that time are described in an HTML (HyperText Markup Language) and then stored in the storage unit 14 .
The locations of such the HTML file and the display data are described in a URL (Uniform Resource Locater) which integratively describes information resources on an internet. A general format of the URL to be utilized in a WWW system is shown as “resource_type://host.domain/path”.
In this case, the format “resource_type” shows the used protocol or services, and designates an http (hypertext transfer protocol) in the image communication apparatus of the present embodiment. In other cases, although such a protocol as “gopher”, “ftp”, “nntp” or the like may be designated, the concrete explanation thereof is omitted. Further, the format “host.domain” shows an address of the server on the internet to be accessed, and is designated in an IP address format or a domain address format. In the image communication apparatus of the present embodiment, the IP address of the WWW server is designated. Furthermore, the format “path” shows a position of the file in the server. For example, in the image communication apparatus of the present embodiment, the location of the HTML file is described as “http://Server_ip_address/□□□/xxx.html”. Further, the location of the display data for confirming the stored transmission image is described as “<IMG SRC = “http://Server_ip_address/□□□/∘∘∘.ΔΔΔ”>” in an HTML tag system.
In this case, the extension “ΔΔΔ” generally uses a compression image file format such as GIF, JPG or the like. Such the extension is interpreted by using a WWW browser being the client application in the WWW system. When demanding the image file such as “∘∘∘.ΔΔΔ” from a WWW server of the image communication apparatus, the WWW browser can display such the image file.
In a step S 108 , the transmission text (i.e., text to be transmitted) including the transmission destination, the instruction reply destination, the fixed-form text, the comment input and the like set in the step S 102 is formed based on a known general-purpose electronic mail format. Further, the location of the HTML file formed and stored in the step S 107 is added to the transmission text of the electronic mail. In a step S 109 , the transmission text of the electronic mail formed in such the manner as above is transmitted to the destination designated based on the transmission function of the electronic mail included in the image transmission apparatus a, as the electronic mail. Then, the transmitted electronic mail is sent to the transmission terminal 24 through the mail server 25 .
Subsequently, with reference to FIG. 4 , it will be explained in detail the operation that the receiver at the transmission destination receives the electronic mail, confirms the display image and provides various instructions to the image communication apparatus a at the transmission source. This flow chart corresponds to the control flow which is performed by the CPU on the basis of a program installed in the memory of the terminal 24 at the transmission destination.
In FIG. 4 , initially in a step S 111 , the receiver who received the electronic mail causes the display unit to display the text contents of the received electronic mail and confirms the displayed contents, by using an electronic mail client application. Such the contents of the electronic mail include information representing that this electronic mail was sent by such special image transmission service as described in the present embodiment, a message to urge the operator to access the added URL by using the WWW browser, information concerning the transmitter, a comment from the transmitter and the like, but the contents described in the electronic mail are not limited thereto. Such the contents can be implicitly managed depending on circumstance.
In a step S 112 , it is judged whether or not the receiver of the electronic mail instructs (by clicking the URL portion described in the HTML text with use of the pointing device or the like) to confirm the image on the basis of the described contents. If there is the receiver's instruction, the flow advances to a step S 113 . In this case, if the electronic mail client application having a function to initiate the WWW browser from the URL described in the text of the electronic mail is utilized, it is possible to immediately confirm the image. However, even if the electronic mail client application not having such the function is utilized, it is possible to confirm the image by initiating the WWW browser independently.
In the step S 113 , the WWW browser demands, from the image communication apparatus a, the HTML file which was formed and stored in the image communication apparatus a in the step S 107 and is represented by the above URL. Since the image communication apparatus a has a WWW server function, the apparatus a supplies responsive to the demand from the WWW browser the designated HTML file to such the WWW browser. Further, the WWW browser analyzes the supplied HTML file. Then, according to the URL in which the display image described in the text and being a source object to be displayed has been described, the WWW browser again demands to display such the display image.
In a step S 114 , since the display image demanded by the WWW browser is supplied, the WWW browser causes the display unit of the terminal 24 to display the supplied display image. As a result, the receiver of the electronic mail can confirm, as a visible image, outline of the image transmitted from the image communication apparatus a on the display unit of the transmission destination terminal 24 logged in by the user at the destination.
After the confirmation of the display image by the receiver of the electronic mail, the flow further advances to a step S 115 . In an image communication system according to the present embodiment, since the image is displayed on the transmission destination terminal 24 , the operator can instruct the apparatus to print out the high-quality print image simultaneously with the confirmation of the image. In the step S 115 , the displaying to instruct whether or not the print image is to be printed out is performed on the same screen as that for the display image, and the instructed contents responsive thereto are transmitted to the image communication apparatus a.
The function included in the WWW browser can be utilized in such an instruction and transmission method. That is, the WWW system includes a CGI (Common Gateway Interface) for transferring the input from the client (i.e., WWW browser) to the server to process such the input based on an external program. For example, in a case where an object (text, bit map data or the like) for instructing the printout of the print image is buried in the HTML text displayed on the WWW browser and it is set that the previously prepared instruction contents are transferred to the server if the object is selected, it is possible that the server which received the transferred instruction analyzes the instruction contents and initiates the program to transfer and print the print data. Further, by utilizing the CGI, it becomes possible to transfer not only the previously prepared instruction contents but also the data inputted by the operator. Therefore, by utilizing the data inputted by the operator, it becomes possible to instruct the system to transfer and print out the print image to not only the specific image communication apparatus but also the arbitrary image communication apparatus based on such the input data. In any case, the above instruction and transmission method is not limited to the method which utilizes the above CGI. That is, any instruction and transmission method may be used, if such the method is based on the application executable between the server (i.e., the image communication apparatus a) and the client (i.e., the terminal displaying the display image). If the printout of the print image is instructed in the step S 115 , the flow advances to a step S 116 to transfer the instruction contents to the image communication apparatus a in the above-described instruction and transmission method.
If the operator does not instruct the apparatus to print out the print image in the step S 115 , the flow advances to a step S 117 . In the step S 117 , it is selected by the operator whether the image data of which printout is not instructed is not to be printed out but to be stored as the file after the print image was transferred, or the image data is to be abandoned or deleted. If it is selected to transfer and store the print image in the step S 117 , the flow advances to a step S 118 . On the other hand, if it is selected to abandon the print image, the flow advances to a step S 119 . In the steps S 118 and S 119 , like the above-described print instruction, the instruction contents are transmitted to the image communication apparatus a.
Subsequently, with reference to the flow chart shown in FIG. 5 , it will be explained in detail the operation that the image communication apparatus a receives the instruction contents from the receiver and analyzes the received contents, and then the process terminates.
In FIG. 5 , initially in a step S 121 , the received instruction contents (either one of instructions in the steps S 116 , S 118 and S 119 ) are stored in the storage unit 14 . After then, the flow advances to a step S 122 to specify the setting on the transmission image in the step S 102 performed at the image transmission time on the basis of the received instruction contents, and transfer such the instruction contents to the reply destination terminal 23 being the instruction reply destination on the basis of the instruction reply destination information. In this case, the transferring of the instruction contents to the instruction reply destination is realized by transmitting the electronic mail. The instruction reply destination which received the instruction contents through the electronic mail can confirm transmission destination's action (i.e., abandonment, storage, print) on the image transmitted from the image communication apparatus a on the basis of the displaying on the display unit of the terminal. For this reason, it becomes possible to confirm whether or not the transmitted image was confirmed by the transmission destination. Further, it becomes possible to confirm the instruction on the transmitted image sent from the partner (i.e., transmission destination). After transferring the instruction contents to the instruction reply destination, the flow advances to a step S 123 .
In the step S 123 , the received instruction contents are analyzed. If the contents instruct to abandon the image data, the flow advances to a step S 124 to delete the image file stored in the storage unit 14 , and then the process terminates. On the other hand, if the contents instruct to transfer and print the image data or transfer and store the image data, the flow advances to a step S 125 . In the step S 125 , the print image is transferred to the previously designated image communication apparatus or to the image communication apparatus based on the data inputted by the operator of the reply destination terminal 24 . In this case, the data transferring from the image communication apparatus a to the image communication apparatus b and the data storing as the file are performed without using the mail server 25 . When such the data transferring and the file storing terminate, the flow advances to a step S 126 . In the step S 126 , based on the instruction from the image communication apparatus a 21 , the image communication apparatus b 22 judges whether or not the print image transferred and stored as the file is to be printed. If not printed, the process terminates as it is. On the other hand, if printed, the flow advances to a step S 127 , the print image is transferred from the storage unit 14 to the image input/output control unit 17 and then printed out by the image output unit 19 . After then, the process terminates.
It should be noted that all the operations shown in the flow charts of FIGS. 3 to 5 are confirmed as a series of communication on the identical image by checking IDs.
As explained above, according to the present embodiment, by utilizing the WWW server function and the transmission/reception function of the electronic mail, the image files of plural image qualities are stored, the file for describing by the HTML text the location of the file suitable to display the image outline is generated from the stored image files, and the electronic mail in which the location of the HTML file was added to transmission guide information concerning the transfer image is transmitted to the electronic mail address at the designated destination. Therefore, the transmitter who transmits the image information from the image communication apparatus a can certainly transmit the information to the specific individual destination, and the receiver who received the electronic mail from the image communication apparatus a can display and confirm the outline of the transmitted display image on the computer terminal, e.g., the terminal 24 , which received the electronic mail, by utilizing a WWW server and client system through the network.
Further, the instruction to the image file based on the operation by the receiver who received the electronic mail is received by a communication means, the image file of desired image quality is selected from among the stored image files according to the received instruction and is transferred to the designated image communication apparatus b, and then the image is outputted based on the transferred image file. Therefore, the image data is directly transferred between the image communication apparatuses on the basis of the judgment by the receiver who confirmed the image, whereby the image reproduced by the high-quality print image data can be transmitted without adding the large-capacity file data probably loading the electronic mail system and the reception terminal.
Furthermore, on the basis of the operation by the operator who received the electronic mail, the designated image communication apparatus b is instructed to output the image file of desired image quality the moment that this file is transferred to this apparatus, to store this image file without the outputting, or to abandon the stored image file. Therefore, it is possible to avoid the transferring of unnecessary information according to circumstances, and also it is possible to postpone the printing output according to secretion of information.
Furthermore, the instruction contents from the receiver of the electronic mail are stored, and the stored instruction contents are transmitted by means of the electronic mail to the destination previously designated by the operator on the transmission side, whereby the transmitted image can certainly reach the destination individual. Therefore, such the transmitted image can be utilized, when the terminal, e.g., the terminal 23 , at the destination designated by the operator on the transmission side confirms that the image was confirmed by the operator himself on the reception side, and that the image was transferred and printed or the image was judged to be unnecessary and thus data abandonment was instructed.
The present invention may be applied to a system constituted by plural apparatuses (e.g., host computer, interface unit, reader, printer and the like) or to a system constituted by a single apparatus (e.g., copy machine or facsimile machine).
The invention employed by a method wherein program codes of a software to realize the functions of the above-described embodiment are supplied to a computer in an apparatus or a system connected to various devices so as to make the devices operative in order to realize the functions of the above-described embodiment and the various devices are operated in accordance with the programs stored in the computer (CPU or MPU) of the system or apparatus is also included in the scope of the present invention.
In such the case, the program codes themselves of the software realize the functions of the above-described embodiment and the program codes themselves and means for supplying the program codes to the computer, e.g., a storage medium in which the program codes have been stored, construct the present invention.
As such the storage medium to store the program codes, for example, a floppy disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM or the like can be used.
Also, in not only a case where the functions of the above-described embodiment are realized by executing the supplied program codes by the computer but also a case where the functions of the above-described embodiment are realized in cooperation with an OS (operating system) by which the program codes operate in the computer or another application software or the like, such the program codes are of course included in the scope of the present invention.
Further, of course, the present invention also includes a case where the supplied program codes are stored in a memory provided for a function expansion board of a computer or a function expansion unit connected to a computer and, after that, a CPU or the like provided for the function expansion board or the function expansion unit executes a part or all of the actual processes based on the instructions of the program codes, and the functions of the above-described embodiment are realized by such the processes.
As explained above, according to the present embodiment, since based on the contents of the electronic mail the image data is transmitted by using the means other than the electronic mail, the image data can be easily and certainly transmitted to the receiver without loading the mail server or the like.
The present invention has been described in connection with the above preferred embodiment. However, the present invention is not limited only to the above-described embodiment, but various modifications are possible without departing from the scope of the appended claims. | A data communication device and method for reducing a load on a mail server. The device transmits image data from an electronic mail without using the electronic mail itself. The device functions by inputting image data, storing the image data, transmitting non-image data relating to the image data to a destination by electronic mail, recognizing an instruction received from that destination, and transmitting the stored image data without using electronic mail, but rather in a way requested in the instruction. | 7 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application Serial No. 60/148,037, filed on Aug. 10, 1999, which is incorporated herein by reference in its entirety.
The present invention is based, in part, on the discovery that aspirin reverses insulin resistance in liver and fat cells, e.g., by targeting IKK-β. Thus, IKK-β was discovered as a target for identifying compounds for the treatment of disorders associated with insulin resistance.
Accordingly, in one aspect, the invention features a method of identifying, evaluating or making a compound or agent, e.g., a candidate compound or agent, for treatment of a disorder characterized by insulin resistance. The method includes evaluating the ability of a compound or agent to interact with, e.g., bind, IKK-β, to thereby identify a compound or agent for the treatment of a disorder characterized by insulin resistance.
In a preferred embodiment, the disorder is diabetes, e.g., Type I or Type II diabetes, obesity, polycystic ovarian disease or syndrome X.
In a preferred embodiment, the compound is: a polypeptide, e.g., a randomly generated polypeptide which binds IKK-β; an antibody, e.g., an intrabody or a randomly generated antibody which binds IKK-β; a small molecule, e.g., a small molecule which binds IKK-β.
In a preferred embodiment, the method further includes contacting the identified compound with IKK-β, e.g., purified IKK-β, to thereby evaluate binding between the compound and IKK-β.
In a preferred embodiment, the method further includes contacting the identified compound with a cell, e.g., a fat cell or a liver cell, to thereby evaluate the effect of the compound on an IKK-β activity of the cell. For example, the ability of the compound to modulate, e.g., reduce or reverse, insulin resistance in a cell.
In a preferred embodiment, the method further includes administering the identified compound to a subject to, evaluate the effect of the compound on insulin resistance. In a preferred embodiment, the subject is a mouse (e.g., a NOD mouse, an ob/ob mouse, a db/db mouse) or a rat (e.g., a Zucker fatty rat, a streptozotocin rat).
In another aspect, the invention features a method of identifying a compound or agent for treatment of a disorder characterized by insulin resistance. The method includes contacting IKK-β, or a cell expressing IKK-β with a test compound; and determining whether the test compound binds to IKK-β, to thereby identify a compound.
Methods for identifying a compound or an agent can be performed, for example, using a cell free assay. For example, the IKK-β can be immobilized to a suitable substrate, e.g., glutathoine sepharose beads or glutathoine derivatized microtiter plates, using a fusion protein which allows for IKK-β to bind to the substrate, e.g., a glutathoine-S-transferase/IKK-β fusion protein.
In a preferred embodiment, the ability of a test compound to bind IKK-β can be determined by detecting the formation of a complex between IKK-β and the compound. The presence of the compound in complex indicates the ability to bind IKK-β.
In a preferred embodiment, IKK-β is further contacted with aspirin.
In another preferred embodiment, a compound is identified using a cell based assay. These methods include identifying a compound based on its ability to modulate, e.g., inhibit, an IKK-β activity of the cell. For example, the ability of a compound to modulate, e.g., reduce or reverse, insulin resistance in a cell, e.g., a fat cell or a liver cell, can be determined.
In a preferred embodiment, the method further includes contacting the identified compound with IKK-β, e.g., purified IKK-β, to thereby evaluate binding between the compound and IKK-β.
In a preferred embodiment, the method further includes contacting the identified compound with a cell, e.g., a fat cell or a liver cell, to thereby evaluate the effect of the compound on an IKK-β activity of the cell. For example, the ability of the compound to modulate, e.g., reduce or reverse, insulin resistance in a cell can be evaluated.
In a preferred embodiment, the method further includes administering the identified compound to a subject to evaluate the effect of the compound on insulin resistance. In a preferred embodiment, the subject is a mouse (e.g., a NOD mouse, an ob/ob mouse, a db/db mouse) or a rat (e.g., a Zucker fatty rat, a streptozotocin rat).
In a preferred embodiment, the compound is: a polypeptide, e.g., a randomly generated polypeptide which interacts with, e.g., binds, IKK-β; an antibody, e.g., an intrabody or a randomly generated antibody which interacts with IKK-β; a small molecule, e.g., a small molecule which interacts with IKK-β.
In a preferred embodiment, the compound is a compound other than aspirin.
In a preferred embodiment, the disorder is diabetes, e.g., Type I or Type II diabetes, obesity, polycystic ovarian disease or syndrome X.
In another aspect, the invention features a method of identifying a compound or agent for treatment of diabetes, e.g., Type I or Type II diabetes. The method includes contacting IKK-β, or a cell expressing IKK-β with a test compound; and determining whether the test compound binds to IKK-β, to thereby identify a compound for treatment of diabetes.
Methods for identifying a compound or an agent can be performed, for example, using a cell free assay. For example, the IKK-β can be immobilized to a suitable substrate, e.g., glutathoine sepharose beads or glutathoine derivatized microtiter plates, using a fusion protein which allows for IKK-β to bind to the substrate, e.g., a glutathoine-S-transferase/IKK-β fusion protein.
In a preferred embodiment, the ability of a test compound to bind IKK-β can be determined by detecting the formation of a complex between IKK-β and the compound. The presence of the compound in complex indicates the ability to bind IKK-β.
In a preferred embodiment, IKK-β is further contacted with aspirin.
In another preferred embodiment, a compound is identified using a cell based assay. These methods include identifying a compound based on its ability to modulate, e.g., inhibit, an IKK-β activity of the cell. For example, the ability of a compound to modulate, e.g., reduce or reverse, insulin resistance in a cell, e.g., a fat cell or a liver cell, can be determined.
In a preferred embodiment, the method further includes contacting the identified compound with IKK-β, e.g., purified IKK-β, to thereby evaluate binding between the compound and IKK-β.
In a preferred embodiment, the method further includes contacting the identified compound with a cell, e.g., a fat cell or a liver cell, to thereby evaluate the effect of the compound on an IKK-β activity of the cell. For example, the ability of the compound to modulate, e.g., reduce or reverse, insulin resistance in a cell.
In a preferred embodiment, the method further includes administering the identified compound to a subject to evaluate the effect of the compound on insulin resistance. In a preferred embodiment, the subject is a mouse (e.g., a NOD mouse, an ob/ob mouse, a db/db mouse) or a rat (e.g., a Zucker fatty rat, a streptozotocin rat).
In a preferred embodiment, the compound is: a polypeptide, e.g., a randomly generated polypeptide which interacts with, e.g., binds, IKK-β; an antibody, e.g., an intrabody or a randomly generated antibody which interacts with IKK-β; a small molecule, e.g., a small molecule which interacts with IKK-β.
In a preferred embodiment, the compound is a compound other than aspirin.
In another aspect, the invention features a method of treating a subject having a disorder characterized by insulin resistance. The method includes: administering a compound or agent which interacts with, e.g., binds, IKK-β, to thereby treat the disorder.
In a preferred embodiment, the disorder is diabetes, e.g., Type I or Type II diabetes, obesity, polycystic ovarian disease or syndrome X.
In a preferred embodiment, the compound is: a compound other than aspirin; a polypeptide, e.g., a randomly generated polypeptide which interacts with IKK-β; an antibody, e.g., an intrabody or a randomly generated antibody which interacts with IKK-β; a small molecule, e.g., a small molecule which interacts with IKK-β. In a preferred embodiment, the method includes administering a nucleic acid encoding one of the above-described compounds. In a preferred embodiment, the compound is a compound identified by a method described herein.
In a preferred embodiment, the compound is administered parenterally, e.g., intravenously, intradermally, subcutaneously, orally (e.g., inhalation). In a preferred embodiment, the administration of the compound is time-released.
In a preferred embodiment, the subject is a human. In another preferred embodiment, the subject is a NOD mouse, an ob/ob mouse, a db/db mouse, a Zucker fatty rat, or a streptozotocin induced rat.
In another aspect, the invention features a method of treating a subject having diabetes, e.g., Type I or Type II diabetes. The method includes administering to a subject a compound or agent which interacts with, e.g., binds, IKK-β, to thereby treat the diabetes.
In a preferred embodiment, the compound is: a compound other than aspirin; a polypeptide, e.g., a randomly generated polypeptide which interacts with IKK-β; an antibody, e.g., an intrabody, e.g., an anti-IKK-β antibody or a randomly generated antibody which interacts with IKK-β, a small molecule, e.g., a small molecule which interacts with IKK-β. In a preferred embodiment, the method includes administering a nucleic acid encoding one of the above-described compounds. In a preferred embodiment, the compound is a compound identified by a method described herein.
In a preferred embodiment, the compound is administered parenterally, e.g., intravenously, intradermally, subcutaneously, orally (e.g., inhalation). In a preferred embodiment, the administration of the compound is time-released.
In a preferred embodiment, the subject is a human. In another preferred embodiment, the subject is a NOD mouse, an ob/ob mouse, a db/db mouse, a Zucker fatty rat, or a streptozotocin induced rat.
In another aspect, the invention features compounds for the treatment of disorders characterized by insulin resistance, identified by the methods described herein.
The terms protein, polypeptide and peptide are used interchangeably herein.
A subject, as used herein, refers to a mammal, e.g., a human. It can also refer to an experimental animal, e.g., an animal model for an insulin-related disorder, e.g., a NOD mouse, an ob/ob mouse, a db/db mouse, a Zucker fatty rat, or a streptozotocin induced mouse or rat. The subject can be a human which is at risk for a disorder characterized by insulin resistance. Such disorders include diabetes, e.g., Type I or Type II, obesity, polycystic ovarian disease and syndrome X.
DETAILED DESCRIPTION OF THE INVENTION
Primary High-Through-Put Methods for Screening Libraries of Peptide Fragments
Various techniques are known in the art for screening gene libraries including existing gene libraries as well as generated mutant gene libraries. Techniques for screening large gene libraries often include cloning the gene library into replicable expression vectors, transforming appropriate cells with the resulting library of vectors, and expressing the genes under conditions in which detection of a desired activity, e.g., in this case, binding to IKK-β, facilitates relatively easy isolation of the vector encoding the gene whose product was detected. Each of the techniques described below is amenable to high through-put analysis for screening large numbers of sequences.
Two Hybrid Systems
Two hybrid (interaction trap) assays can be used to identify peptides which bind IKK-β (see e.g., U.S. Pat. No. 5,283,317; PCT publication WO94/10300; Zervos et al. (1993) Cell 72:223-232; Madura et al. (1993) J Biol Chem 268:12046-12054; Bartel et al. (1993) Biotechniques 14:920-924; and Iwabuchi et al. (1993) Oncogene 8:1693-1696). These assays rely on detecting the reconstitution of a functional transcriptional activator mediated by protein-protein interactions with a bait protein. In particular, these assays make use of chimeric genes which express hybrid proteins. The first hybrid comprises a DNA-binding domain fused to the bait protein. e.g., IKK-β or a fragment thereof. The second hybrid protein contains a transcriptional activation domain fused to a “fish” protein, e.g. an expression library. If the fish and bait proteins are able to interact, they bring into close proximity the DNA-binding and transcriptional activator domains. This proximity is sufficient to cause transcription of a reporter gene which is operably linked to a transcriptional regulatory site which is recognized by the DNA binding domain, and expression of the marker gene can be detected and used to score for the interaction of the bait protein IKK-β with another protein.
Display Libraries
In one approach to screening assays, the candidate peptides are displayed on the surface of a cell or viral particle, and the ability of particular cells or viral particles to bind IKK-β or a fragment thereof via the displayed product is detected in a “panning assay”. For example, the gene library can be cloned into the gene for a surface membrane protein of a bacterial cell, and the resulting fusion protein detected by panning (Ladner et al., WO 88/06630; Fuchs et al. (1991) Bio/Technology 9:1370-1371; and Goward et al. (1992) TIBS 18:136-140).
A gene library can be expressed as a fusion protein on the surface of a viral particle. For instance, in the filamentous phage system, foreign peptide sequences can be expressed on the surface of infectious phage, thereby conferring two significant benefits. First, since these phage can be applied to affinity matrices at concentrations well over 10 13 phage per milliliter, a large number of phage can be screened at one time. Second, since each infectious phage displays a gene product on its surface, if a particular phage is recovered from an affinity matrix in low yield, the phage can be amplified by another round of infection. The group of almost identical E. coli filamentous phages M13, fd., and fl are most often used in phage display libraries. Either of the phage gIII or gVIII coat proteins can be used to generate fusion proteins without disrupting the ultimate packaging of the viral particle. Foreign epitopes can be expressed at the NH 2 -terminal end of pIII and phage bearing such epitopes recovered from a large excess of phage lacking this epitope (Ladner et al. PCT publication WO 90/02909; Garrard et al., PCT publication WO 92/09690; Marks et al. (1992) J. Biol. Chem. 267:16007-16010; Griffiths et al. (1993) EMBO J 12:725-734; Clackson et al. (1991) Nature 352:624-628; and Barbas et al. (1992) PNAS 89:4457-4461).
A common approach uses the maltose receptor of E. coli (the outer membrane protein, LamB) as a peptide fusion partner (Charbit et al. (1986) EMBO 5, 3029-3037). Oligonucleotides have been inserted into plasmids encoding the LamB gene to produce peptides fused into one of the extracellular loops of the protein. These peptides are available for binding to IKK-β. Other cell surface proteins, e.g., OmpA (Schorr et al. (1991) Vaccines 91, pp. 387-392), PhoE (Agterberg, et al. (1990) Gene 88, 37-45), and PAL (Fuchs et al. (1991) Bio/Tech 9, 1369-1372), as well as large bacterial surface structures have served as vehicles for peptide display. Peptides can be fused to pilin, a protein which polymerizes to form the pilus-a conduit for interbacterial exchange of genetic information (Thiry et al. (1989) Appl. Environ. Microbiol. 55, 984-993). Because of its role in interacting with other cells, the pilus provides a useful support for the presentation of peptides to the extracellular environment. Another large surface structure used for peptide display is the bacterial motive organ, the flagellum. Fusion of peptides to the subunit protein flagellin offers a dense array of may peptides copies on the host cells (Kuwajima et al. (1988) Bio/Tech. 6, 1080-1083). Surface proteins of other bacterial species have also served as peptide fusion partners. Examples include the Staphylococcus protein A and the outer membrane protease IgA of Neisseria (Hansson et al. (1992) J. Bacteriol. 174, 4239-4245 and Klauser et al. (1990) EMBO J. 9, 1991-1999).
In the filamentous phage systems and the LamB system described above, the physical link between the peptide and its encoding DNA occurs by the containment of the DNA within a particle (cell or phage) that carries the peptide on its surface. Capturing the peptide captures the particle and the DNA within. An alternative scheme uses the DNA-binding protein Lacd to form a link between peptide and DNA (Cull et al. (1992) PNAS USA 89:1865-1869). This system uses a plasmid containing the LacI gene with an oligonucleotide cloning site at its 3′-end. Under the controlled induction by arabinose, a LacI-peptide fusion protein is produced. This fusion retains the natural ability of LacI to bind to a short DNA sequence known as LacO operator (LacO). By installing two copies of LacO on the expression plasmid, the LacI-peptide fusion binds tightly to the plasmid that encoded it. Because the plasmids in each cell contain only a single oligonucleotide sequence and each cell expresses only a single peptide sequence, the peptides become specifically and stably associated with the DNA sequence that directed its synthesis. The cells of the library are gently lysed and the peptide-DNA complexes are exposed to a matrix of immobilized receptor to recover the complexes containing active peptides. The associated plasmid DNA is then reintroduced into cells for amplification and DNA sequencing to determine the identity of the peptide ligands. As a demonstration of the practical utility of the method, a large random library of dodecapeptides was made and selected on a monoclonal antibody raised against the opioid peptide dynorphin B. A cohort of peptides was recovered, all related by a consensus sequence corresponding to a six-residue portion of dynorphin B. (Cull et al. (1992) Proc. Natl. Acad. Sci. U.S.A. 89-1869).
This scheme, sometimes referred to as peptides-on-plasmids, differs in two important ways from the phage display methods. First, the peptides are attached to the C-terminus of the fusion protein, resulting in the display of the library members as peptides having free carboxy termini. Both of the filamentous phage coat proteins, pIII and pVIII, are anchored to the phage through their C-termini, and the guest peptides are placed into the outward-extending N-terminal domains. In some designs, the phage-displayed peptides are presented right at the amino terminus of the fusion protein. (Cwirla, et al. (1990) Proc. Natl. Acad. Sci. U.S.A. 87, 6378-6382) A second difference is the set of biological biases affecting the population of peptides actually present in the libraries. The LacI fusion molecules are confined to the cytoplasm of the host cells. The phage coat fusions are exposed briefly to the cytoplasm during translation but are rapidly secreted through the inner membrane into the periplasmic compartment, remaining anchored in the membrane by their C-terminal hydrophobic domains, with the N-termini, containing the peptides, protruding into the periplasm while awaiting assembly into phage particles. The peptides in the LacI and phage libraries may differ significantly as a result of their exposure to different proteolytic activities. The phage coat proteins require transport across the inner membrane and signal peptidase processing as a prelude to incorporation into phage. Certain peptides exert a deleterious effect on these processes and are underrepresented in the libraries (Gallop et al. (1994) J. Med. Chem. 37(9):1233-1251). These particular biases are not a factor in the LacI display system.
The number of small peptides available in recombinant random libraries is enormous. Libraries of 10 7 -10 9 independent clones are routinely prepared. Libraries as large as 10 11 recombinants have been created, but this size approaches the practical limit for clone libraries. This limitation in library size occurs at the step of transforming the DNA containing randomized segments into the host bacterial cells. To circumvent this limitation, an in vitro system based on the display of nascent peptides in polysome complexes has recently been developed. This display library method has the potential of producing libraries 3-6 orders of magnitude larger than the currently available phage/phagemid or plasmid libraries. Furthermore, the construction of the libraries, expression of the peptides, and screening, is done in an entirely cell-free format.
In one application of this method (Gallop et al. (1994) J. Med. Chem. 37(9):1233-1251), a molecular DNA library encoding 10 12 decapeptides was constructed and the library expressed in an E. coli S30 in vitro coupled transcription/translation system. Conditions were chosen to stall the ribosomes on the mRNA, causing the accumulation of a substantial proportion of the RNA in polysomes and yielding complexes containing nascent peptides still linked to their encoding RNA. The polysomes are sufficiently robust to be affinity purified on immobilized receptors in much the same way as the more conventional recombinant peptide display libraries are screened. RNA from the bound complexes is recovered, converted to cDNA, and amplified by PCR to produce a template for the next round of synthesis and screening. The polysome display method can be coupled to the phage display system. Following several rounds of screening, cDNA from the enriched pool of polysomes was cloned into a phagemid vector. This vector serves as both a peptide expression vector, displaying peptides fused to the coat proteins, and as a DNA sequencing vector for peptide identification. By expressing the polysome-derived peptides on phage, one can either continue the affinity selection procedure in this format or assay the peptides on individual clones for binding activity in a phage ELISA, or for binding specificity in a completion phage ELISA (Barret, et al. (1992) Anal. Biochem 204,357-364). To identify the sequences of the active peptides one sequences the DNA produced by the phagemid host.
Other Methods of Identifying Small Molecules which Interact with IKK-β
Computer-based analysis of a protein with a known structure can also be used to identify molecules which will bind to the protein. Such methods rank molecules based on their shape complementary to a receptor site. For example, using a 3-D database, a program such as DOCK can be used to identify molecules which will bind to IKK-β. See DesJarlias et al. (1988) J. Med. Chem. 31:722; Meng et al. (1992) J. Computer Chem. 13:505; Meng et al. (1993) Proteins 17:266; Shoichet et al. (1993) Science 259:1445. In addition, the electronic complementarity of a molecule to a targeted protein can also be analyzed to identify molecules which bind to the target. This can be determined using, for example, a molecular mechanics force field as described in Meng et al. (1992) J. Computer Chem. 13:505 and Meng et al. (1993) Proteins 17:266. Other programs which can be used include CLIX which uses a GRID force field in docking of putative ligands. See Lawrence et al. (1992) Proteins 12:31; Goodford et al. (1985) J. Med. Chem. 28:849; Boobbyeretal. (1989) J. Med. Chem. 32:1083.
Secondary Screens
The high through-put assays described above can be followed by secondary screens in order to identify further biological activities which will, e.g., allow one skilled in the art to differentiate agonists from antagonists. For example, a cell based assay can be used to identify compounds which have the ability to modulate, e.g., inhibit, IKK-β activity of a cell. For example, the ability of a compound to modulate, e.g., inhibit, insulin resistance in a cell in vitro or in vivo. Cultured cells which can be used to determine the effect of a compound on insulin resistance include liver and fat cells.
For in vivo testing of a compound to reduce or inhibit insulin resistance, the compound can be administered to an accepted animal model. Experimental models for insulin resistance include NOC mice, ob/ob mice, db/db mice, Zucker fatty rats and streptozotocin induced rats.
Once the core sequence of interest is identified, it is routine to perform for one skilled in the art to obtain analogs and fragments. | The invention features a method of identifying, evaluating or making a compound or agent, e.g., a candidate compound or agent, for treatment of a disorder characterized by insulin resistance. The method includes evaluating the ability of a compound or agent to interact with, e.g., bind, IKK-β, to thereby identify a compound or agent for the treatment of a disorder characterized by insulin resistance. The invention also features compounds for treating insulin resistance identified by such methods, and methods of treating a subject having a disorder characterized by insulin resistance by administering such agents. | 6 |
TECHNICAL FIELD
This invention relates to semiconductor processing of substrates, and more particularly to shadow frames used to prevent deposition on the edge and backside of a substrate.
BACKGROUND
The semiconductor industry has been using single substrate (silicon wafer) processing chambers for some time because the chamber volume can be minimized, contamination of the substrate reduced, process control increased. Therefore, yields are improved. Further, vacuum systems have been developed, such as described in U.S. Pat. No. 4,951,601, that allow several sequential processing steps to be carried out in a plurality of vacuum processing chambers connected to a central transfer chamber, so that several processing steps can be performed on a substrate without its leaving a vacuum environment. This further reduces the possibility of contamination of the substrates.
Recently the interest in providing large glass substrates with active thin film transistors thereon for applications such as active matrix TV and computer displays has been heightened. These large glass substrates require vacuum processing chambers for deposition of thin films. The basic methods and processing chambers, e.g., plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD or “sputtering”) etch chambers and the like, are similar to those used for depositing layers and patterning thin films on silicon wafers. A practicable system that can perform multiple process steps on glass substrates is disclosed by U.S. Pat. No. 5,512,320, hereby incorporated by reference. However, because of the large size of the glass substrates, several problems have been noted in their handling and processing in vacuum processing chambers.
During processing, the edge and backside of the glass substrate must be protected from deposition. A deposition-masking rectangle or shadow frame is placed about the periphery of the substrate to prevent processing gases or plasma from reaching the edge and backside of the substrate in a CVD chamber for example. The susceptor, with a substrate mounted thereon, can have a shadow frame which will surround and cover several millimeters of the periphery of the front surface of the substrate. This will prevent edge and backside deposition on the substrate. If, however, the shadow frame is not properly centered with respect to the substrate during processing, the amount of shadowing that occurs on each edge of the substrates will be unequal and unacceptable.
In substrate processing in general, and in PVD (sputtering) processing in particular, particulates which are present and are generated in the processing chamber can contaminate and destroy the substrate being processed. When such particulates (also known as “free” particulates) land on the substrate being processed, they contaminate a small area of the substrate which can be discarded if the substrate is die cut into separate chips. However, when a large substrate is intended for subsequent use as a single item (e.g. as a flat panel display), one defect causes the whole unit to be rejected.
The contaminating particulates originate from several sources. Incomplete or defective cleaning of the chamber allows particulates to remain in the chamber and cause contamination. However, even when the processing chamber is clean, contaminants can be and are generated during the sputtering process. One type of contaminating particulate originates from sputter deposited material which has deposited itself on processing chamber surfaces other than the substrate intended for deposition, and subsequentially detaches (peels off or falls off) from the location inside the vacuum processing chamber where it originally had been deposited. These particulates are usually cool, multi-molecular sized specks of sputter deposited material which were hot during the sputtering process, but have since cooled as a result of their contact with surrounding surfaces. However, unlike the hot material being sputter deposited when the cool specks (particulates) land on and are embedded in the substrate, they can create defects which cause rejection of the substrate.
Another source of particulates is electrical arcing between the highly charged (biased) target and its surrounding uncharged (grounded) pieces. Arcing occurs in PVD processing chambers at locations between the edge of the target and surrounding surfaces (usually a shield enclosing the target and protruding into the space adjacent to the target which is known as “the dark space ring or groove”). Arcing between adjacent pieces causes a severe localized temperature spike which in most cases releases molecules of one or both of the materials between which the spark arcs. If the released molecules settle on the substrate, at best, they create a slight but acceptable anomaly in the coating pattern, or at worst when a particulate is a foreign material, the substrate will be contaminated and will have to be rejected.
SUMMARY
In one aspect, the invention is directed to a vacuum processing chamber. The chamber has walls defining a cavity for processing a substrate, a substrate support for supporting a substrate being processed in the cavity, a shadow frame for preventing processing of a perimeter portion of the substrate, and a shadow frame support supporting the shadow frame within the cavity. The shadow frame is positionable with a gap between an underside of the shadow frame and an upper surface of the substrate, and the shadow frame support has at least one conductive element insulated from the walls and establishing a conductive path from the shadow frame to outside the cavity.
Implementations of the invention may include the following. The substrate support may include a susceptor having an upper surface to support the substrate, and a plurality of lift pins vertically movable relative to the susceptor to contact the underside of the substrate to support the substrate. A bias voltage source may be coupled to the conductive element and configured to apply a bias voltage to the shadow frame selected to prevent arcing between a portion of the substrate being processed and the shadow frame. The bias voltage source may be configured to apply a second bias voltage to the shadow frame to attract charged particles, released by termination of a plasma within the chamber, to the shadow frame, so that there is a preferential accumulation of such particles on the shadow frame relative to the substrate. A voltage measurement device may be coupled to the conductive element and configured to measure a voltage of the shadow frame. A grounding circuit may couple the conductive element to ground, and it may be configured so as to discharge a first charge accumulated by the shadow frame during processing. The discharge may maintain the shadow frame at a potential sufficient to substantially prevent arcing between the shadow frame and the substrate. The grounding circuit may include a resistor to continuously discharge charge accumulated by the shadow frame, a switch connecting the at least one conductive element to ground, a voltage measurement device configured to close the switch if the charge on the shadow frame exceeds a threshold, or a control system configured to close the switch after a predetermined number of substrates have been processed. The conductive element may be a height-adjustable generally vertical member, which may be adjusted to determine the height of the shadow frame within the cavity. The shadow frame support includes a mounting flange insulated from the conductive element. The height-adjustable member may include an upper member having an at least partially cone-shaped upper end in physical and electrical contact with a mating feature in an underside of the shadow frame and a lower end having a threaded central aperture, a lower member having an externally threaded upper portion in threaded engagement with the threaded central aperture of the upper member, and a lock nut in threaded engagement with the externally threaded upper portion and configured to bear against the lower end of the upper member to lock the upper member relative to the lower member. The support may be movable in a vertical direction to move the substrate between a loading height and a processing height, above the loading height;
In another aspect, the invention is directed to a process for sputter deposition from a sputtering target onto a surface of a substrate positioned in a processing region of a vacuum chamber. In the process, a plasma is generated between the target and the surface of the substrate, material is sputtered from the target onto the surface of the substrate to form sputter deposited material thereupon, the generation of the plasma is terminated as to release particles having a charge, and a bias voltage is applied to a shadow frame sufficient to attract at least a portion of the particles to the shadow frame, whereby the portion of the particles does not contaminate the surface of the substrate.
Implementations of the invention may include the following. The plasma may be moved between first and second positions in the vacuum chamber by moving a magnet in a magnet region of the vacuum chamber between a home position and a remote position at extremes of a range of the magnet. The step of applying a bias voltage may occur while the magnet is substantially at said home position. The sputtering step may be performed with a substantial quantity of argon gas in the vacuum chamber and the bias voltage may be a positive voltage.
In another aspect, the invention is directed to a process for sputter deposition from a sputtering target onto a surface of a substrate positioned in a processing region of a vacuum chamber. In the process a plasma is generated between the target and the surface of the substrate, material is sputtered from the target onto the surface of the substrate to form sputter deposited material thereupon, and the generation of the plasma is terminated. Charge is discharged from a shadow frame at a rate sufficient to maintain the shadow frame at a potential that substantially prevents arcing between the shadow frame and the substrate.
Implementations of the invention may include the following. The charge may be discharged continuously through a resistor. The voltage of the shadow frame may be measured, and the charge may be discharged when the measured voltage exceeds a threshold. The charge may be discharged after a predetermined number of substrates have been processed.
In another aspect, the invention is directed to a vacuum processing chamber. The chamber has walls defining a cavity for processing a substrate within the cavity, a substrate support for supporting the substrate being processed in the cavity, a shadow frame for preventing processing of a perimeter portion of a substrate, and a shadow frame support supporting the shadow frame within the cavity. The shadow frame is positionable with a gap between an underside of the shadow frame and an upper surface of the substrate, and the shadow frame support has a plurality of conductive elements insulated from the walls and establishing at least one conductive path from the shadow frame to outside the cavity in order to discharge charge from the shadow frame at a rate sufficient to prevent a voltage differential from accumulating between the shadow frame and the substrate which would cause arcing therebetween.
Among the advantages of the invention are the following. Arcing between the substrate and the shadow frame may be reduced, thereby decreasing the accumulation of contaminating particles on the substrate.
The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a cross-sectional view of a processing chamber according to the invention.
FIG. 2 is a cross-sectional view of the chamber of FIG. 1 .
FIG. 3 is a top view of a shadow frame from the chamber of FIG. 1 .
FIG. 4 is a bottom view of the shadow frame of FIG. 3 .
FIG. 5 is a cross-sectional view of the shadow frame of FIG. 3 taken along line 5 — 5 .
FIG. 6 is partially a detailed cross-sectional view of the processing chamber of FIG. 1 with a susceptor at a loading height, and partially a schematic circuit diagram.
FIG. 7 is a detailed cross-sectional view of the processing chamber of FIG. 1 with the susceptor at a processing height.
Like reference numbers and designations in the various drawings indicate like elements.
DETAILED DESCRIPTION
As noted, a problem with prior art systems in which the shadow frame is grounded (e.g., through electrical contact with the susceptor) is arcing between the substrate and the shadow frame. Such arcing is a particular problem in the processing of insulative substrates such as glass rather than semiconductor substrates because the latter type of substrate effectively grounds the deposited layers to the susceptor whereas the former insulates the two and allows the deposited layers to accumulate charge. Discharge of such charge produces the arcing and damages the substrate involved and generates particles which may adversely effect the processing of subsequent substrates.
In one attempted solution to the arcing problem, a shadow frame may be supported within the chamber in such a way as to electrically float. However, in experiments with an electrically floating shadow frame, arcing was nevertheless observed. The observed arcing occurred after a number of depositions, e.g., approximately every tenth substrate. Without being limited to any particular theory, one possible explanation is that arcing occurs toward the end of or after deposition on a substrate when the deposited layers on the upper surface of the substrate accumulate sufficient negative charge to arc to the shadow frame. With a floating shadow frame, however, the shadow frame itself picks up a negative charge and, once sufficient charge has been accumulated, when a fresh substrate is introduced to the chamber, arcing may occur between the shadow frame and the substrate before the substrate has accumulated charge of the same sign as that on the shadow frame.
In a floating shadow frame, the bulk of the charge acquisition by the shadow frame appears to occur after termination of deposition (e.g., when flow of reactive gases and plasma generation are terminated). By way of example, in one process commenced with a shadow frame initially uncharged, the shadow frame quickly picked up a negative charge of approximately −30-40V. After deposition was terminated, the negative charge further increased in magnitude to below −250V.
Another problem is that in certain systems there is a particle accumulation on the upper surface of the substrate adjacent one edge. This may be associated with the home position of a magnet used in plasma generation. In such systems, the magnet reciprocates from side to side over the substrate with a target interposed between the substrate and magnet. A plasma is generated between the target and substrate to facilitate deposition. It is in the home position (typically above one edge of the substrate) that generation of the plasma is initiated and terminated at the beginning of and end of deposition. One possible explanation is that negatively charged particles trapped in the plasma fall to the substrate when the plasma is terminated.
As shown in FIGS. 1 and 2, a processing chamber 20 has a plurality of walls 22 A- 22 F which bound and define a cavity 30 in which substrates may be processed. Substrate ingress and egress may be provided through one or more gate valves (not shown). A susceptor 32 which may generally be formed as a rectangular plate, has a flat central upper surface portion 34 for supporting a substrate 36 during processing. The substrate has an upper surface 38 on which material is to be deposited, a lower surface or underside 40 , and a perimeter comprising the four edges of the substrate. A central shaft 42 depends from the susceptor and serves as a pedestal for supporting the susceptor to raise and lower the susceptor as described below. A pin plate 44 is located below the susceptor 32 and is supported by a sleeve 46 encompassing the shaft 42 and mounted to permit the pin plate to be raised independently of the susceptor. Extending upward from the pin plate are a plurality of lift pins 48 and alignment pins 49 accommodated by apertures in the susceptor. The upper ends or tips of the lift pins are configured to contact the underside of a substrate to hold the substrate elevated above the susceptor during transfer of the substrate to and from the chamber by a robot (not shown). During transfer, the end effector (also not shown) of the robot is accommodated between the susceptor and underside of the substrate, passing laterally around the lift pins.
In operation, the end effector introduces the substrate to the chamber through a gate valve. With the lift pins protruding through the upper surface of the susceptor, the combined susceptor and pin plate are elevated slightly. If the substrate is not laterally aligned with its target position, the elevation causes the angled sides of one or more of the alignment pins 49 to contact the substrate perimeter and shift the substrate laterally toward the target position. As the lift pins are raised to an intermediate stage of elevation, the lift pins 48 contact the underside of the substrate and raise the substrate slightly above the end effector. The end effector may then be withdrawn. Finally, the susceptor may be further raised (absolutely and relative to the pin plate) to lift the substrate off the lift pins (the lift pins receding into the apertures within the susceptor) and raise the substrate to a processing height (see FIG. 7 ).
When the substrate is at the processing height as shown in FIG. 7, a perimeter portion of the upper surface of the substrate is in close parallel relation to an inboard edge of the underside of a shadow frame 60 . As described below in greater detail, the shadow frame 60 is discharged at a rate sufficient to prevent a large voltage differential from accumulating betweeen the shadow frame and the substrate so as to substantially prevent arcing therebetween.
As shown in FIGS. 3 and 4, the shadow frame 60 is formed in rectangular shape with a central aperture 61 as the unitary combination of side members 62 A, 62 B, 64 A and 64 B. In the illustrated embodiment, the side members 62 A and 62 B are shorter than the members 64 A and 64 B and are designated as ends. The side members 62 A, 62 B, 64 A, and 64 B have substantially identical overall cross-section. As shown in FIG. 5, the lower surface of each side member has a generally flat outboard portion 66 and a generally flat inboard portion 68 , separated from the outboard portion by an angled bevel or shoulder 70 . The inboard portion 68 is dimensioned to overlie (with a slight gap) the substrate adjacent the substrate 36 perimeter during processing (see FIG. 7 ). The upper surface of each member 62 A, 62 B, 64 A, 64 B has a generally flat outboard portion 72 parallel to the outboard portion 66 and a generally flat inboard portion 74 angled downward from the outboard portion 72 to reach close proximity with the inboard portion 68 adjacent the central aperture of the frame.
Referring to FIG. 6, the shadow frame is supported by four supports 80 which contact the underside of the shadow frame. Each support 80 includes an electrical feedthrough 82 having a vertically extending conductor/shaft 84 and a mounting flange 86 electrically insulated from the shaft 84 . The flange 86 is secured to the underside of the bottom wall 22 B of the chamber with the shaft 84 extending through an aperture in such wall and into the cavity 30 . In the illustrated embodiment, the feedthrough 82 may be provided by a high voltage, medium current feedthrough, e.g., available from MDC Vacuum Products, Inc., of Haywood, Calif. In the illustrated embodiment, spanning between the shaft 84 and the shadow frame 60 each support 80 includes an adjustable engagement member 88 having an internally threaded stainless steel distal tip portion 90 . The upper end of the tip 90 has a conical surface 92 for engaging the shadow frame. The tip 90 has an internally threaded aperture extending upward from its lower end which receives a mating externally threaded upper portion of a proximal extension portion 94 . The extension 94 has an aperture extending upward from its lower end, into which the upper portion of the shaft 84 is press fit. A lock nut 96 rides on the threaded upper end of the extension 94 and may be tightened against the bottom end surface of the tip 90 to lock the tip 90 in place. By rotation of the tip 90 relative to the extension 94 , the tip 90 may be raised and lowered to establish a preferred height for the shadow frame to accommodate substrates of different thickness and/or vary the gap between the substrate and frame and/or vary the gap between the substrate and the target. Each conical surface 92 rides in an associated elongated conical slot 100 in the lower outboard surface portion 66 of the shadow frame. In the illustrated embodiment, there are four slots 100 (FIG. 4) aligned so as to converge in the center of the shadow frame. With thermal expansion or contraction of the shadow frame relative to the remainder of the chamber, the conical surfaces 92 may slide within the slots 100 .
A sputtering target 120 is provided in the chamber above the shadow frame and substrate. As shown in FIGS. 1 and 2, the target 120 divides the chamber in two, defining a magnet chamber portion above the target and a reaction portion below the target. The target is generally rectangular and of somewhat greater area than the substrate and the susceptor. A magnet 124 is carried above the target 120 via a drive mechanism 126 and may be reciprocated over the target between a first or home position proximate one side of the chamber (shown in solid lines in FIG. 1) and a second position proximate an opposite side of the chamber (shown in broken lines in FIG. 1 ). The drive mechanism may be coupled to a control system 130 which also controls the movement of the susceptor, pin plate, valves, plasma generator, vacuum pumps, reactant gas supplies, and other elements of the system.
In operation, a gas (e.g., argon) is introduced into the processing chamber and the gas molecules are ionized as a result of a combination of magnetic field and DC power. Once ionized, the gas molecules bombard the sputtering target 120 , causing the target material to be released into chamber 30 as molecular size ballistic particles. The particles of the target material then travel through the chamber to bombard and accumulate on the substrate 36 . In addition, the plasma may be moved in the vacuum chamber by moving a magnet in the magnet region of the vacuum chamber between a home position and a remote position (shown in phantom).
Referring to FIG. 6, in one embodiment, the conductors or conductor shafts 84 may be linked to ground via a resistor 140 . An individual resistor 140 may be associated with each feedthrough 82 or a single resistor may be connected to more than one feedthrough. The value of the resistor(s) is chosen to allow a gradual discharge of charge from the shadow frame. The rate of discharge is such to maintain the shadow frame at a potential sufficient to substantially prevent arcing between the shadow frame and the substrate. Specifically, the rate of discharge is fast enough to prevent so much charge from accumulating on the shadow frame so that the potential of the shadow frame sufficiently below the potential of the substrate that arcing occurs, but slow enough that if the substrate acquires additional negative charge during processing, the potential of the substrate will not drop so far below the potential of the shadow frame that arcing occurs. In one exemplary application, the value of the resistor may be chosen so that during sequential processing, the shadow frame remains at a potential of approximately −30V or such other amount as may be sufficient to avoid arcing between the shadow frame and a substrate that acquires a negative charge of even greater magnitude.
In another embodiment shown in FIG. 6, the conductor may be coupled to voltage measurement equipment 150 (which may be included in the control system 130 ) to monitor the charge accumulation of the shadow frame. When the charge exceeds a certain amount, the charge may entirely or partially be discharged to ground such as via a switch 152 which may be directly coupled to ground or may be coupled to ground via a resistor 154 . Alternatively, the discharge to ground may be initiated after a predetermined number of substrates have been processed, which predetermined number is less than the number of sequential substrates being processed which would be expected to induce arcing.
In a further embodiment shown in FIG.6, shaft/conductors 84 may be coupled to a voltage source 156 to maintain the shadow frame at a bias voltage. For example, the bias voltage could be a −30V DC potential. The bias voltage may be selected by the user to be appropriately related to the extremes of voltage of the deposited layers on the upper surface of the substrate so that arcing does not occur at any point during processing. In the exemplary application, the extremes may be about from a voltage of between −200V to −300V after processing and approximately neutral voltage at the beginning of processing. In this embodiment, a second opposite bias voltage may be briefly applied to the shadow frame upon termination of the plasma to prevent the particles in the plasma from falling to the substrate. In the exemplary application, if, contemporaneously with terminating the plasma, the shadow frame is raised to +30V, negatively charged particles trapped in the plasma will be drawn to the shadow frame rather than to the substrate. In still another exemplary application, the bias voltage is applied while the magnet is at the home position.
A number of embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. For example, the invention may be adapted for use with a variety of chamber configurations. Various parameters may be influenced by and optimized for the particular chamber involved and process being performed. Accordingly, other embodiments are within the scope of the following claims. | A vacuum processing chamber with walls defining a cavity for processing a substrate. The processing chamber includes a substrate support for supporting a substrate being processed in the cavity, a shadow frame for preventing processing of a perimeter portion of the substrate, and a shadow frame support supporting the shadow frame within the cavity. The shadow frame is positionable with a gap between an underside of the shadow frame and an upper surface of the substrate. At least one conductive element insulated from the walls and establishes a conductive path from the shadow frame to outside the cavity. The conductive path may be used to discharge charge from the shadow frame at a rate sufficient to prevent a voltage differential from accumulating between the shadow frame and the substrate which would cause arcing therebetween, or to apply a bias voltage to the shadow frame sufficient to attract particles to reduce contamination of the substrate. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to a maximum likelihood sequence estimation apparatus which improves data transmission characteristic by eliminating distortion due to sampling timing error or inter symbol interferences (ISI) in case of transmitting data through time varying transmission paths causing inter symbol interferences.
Since it is difficult to obtain an optimum sampling timing from a receiving signal distorted by inter symbol interferences, a system is proposed to equalize and decode the signal using the signal sampled at a sampling frequency equal to an integer number of times of the symbol rate. One example of such system is to equalize and decode using a decision feedback equalizer of fractional interval. (See, for example, "Decision Feedback Equalization for Digital Cellular Radio" by S. Chennakeshu, et al., IEEE, Conf. Record on ICC '91, 339.4.1-339.4.5.)
A maximum likelihood sequence estimation apparatus is known to be an optimum system to eliminate distortion due to inter symbol interferences. (See, for example, "Digital Communications" by J. G. Proakis, McGraw-Hill, 1983.)
However, the conventional maximum likelihood sequence estimation system is incapable of correcting distortion due to sampling timing error because only known sampling frequency is equal to the symbol rate.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provide a maximum likelihood sequence estimation apparatus capable of eliminating distortion due to sampling timing error from the optimum sampling timing and also distortion caused by inter symbol interferences.
For this end, the maximum likelihood sequence estimation apparatus according to the present invention is to decode a digital data signal and comprises sampling means to perform sampling and output a received signal by sampling pulses having a constant time interval T and N different sampling phases, operation means to operate branch metric of the received signal sampled by the N different sampling phases, and means to perform the maximum likelihood sequence estimation of the branch metric.
The maximum likelihood sequence estimation apparatus according to the present invention will be understood from the following description by reference to the accompanying drawings illustrating preferred embodiments of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of one embodiment of the first invention of the maximum likelihood sequence estimation apparatus;
FIG. 2 is a block diagram of one embodiment of the second invention of the maximum likelihood sequence estimation apparatus;
FIG. 3 is a block diagram of one embodiment of the third invention of the maximum likelihood sequence estimation apparatus;
FIG. 4 is a block diagram of one embodiment of the fourth invention of the maximum likelihood sequence estimation apparatus;
FIG. 5 is an example of the branch metric calculation circuit;
FIG. 6 is an example of the branch metric composite circuit;
FIG. 7 is a block diagram of one example of a channel impulse response estimation circuit;
FIG. 8 is a block diagram of one example of a channel impulse response estimation circuit;
FIG. 9 is a block diagram of one example of the branch metric composite circuit; and
FIG. 10 is a block diagram of one example of the sampling and output means for sampling the received signal by sampling in N different sampling phases using sampling pulses having a constant time interval T and N (N>1) different phases.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, represented by reference numerals 10, 11(1) through 11(N-1), 12, 13(1) through 13(N), 14, 15 and 16 are an input terminal, delay circuits to provide different delay times, a pulse generator circuit, samplers, a branch metric calculation circuit, a Viterbi processor and an output terminal, respectively.
A received input signal through the input terminal 10 is delayed by a bank of delay circuits 11(1) through 11(N-1) before reaching respective samplers 13(2) through 13(N). Also, the received signal is directly applied to the sampler 13(1) with no delay. The samplers 13(1) through 13(N) perform signal sampling of the received signal, and the outputs from the delay circuits 11(1) through 11(N) at the timing of the pulse generated from the pulse generator 12. When the sampling pulse frequency is 1/T, the delay times of the delay circuits 11(1) through 11(N-1) are set to iT/N (i=1, 2, . . . , N-1), thereby sampling the received signal in sequentially different sampling phases by the samplers 13(1) through 13(N).
An alternative sampling means of sampling the received signal in different sampling phases is illustrated in FIG. 10. Shown in FIG. 10 is a block diagram of one example of the sampling means to perform sampling the received signal in N different sampling phases using sampling pulses of N (N>1) different phases but each having a constant time interval T. In FIG. 10, a reference numeral 1004 is an input terminal, 1000 is a pulse generator to generate a sampling pulse having frequency equal to 1/NT, 1001(1) through 1001(N) are frequency dividers to divide at different phases, 1002(1) through 1002(N) are samplers and 1003(1) through 1003(N) are output terminals.
In FIG. 10, the output from the pulse generator 1000 which generates the sampling pulse having the frequency equal to 1/NT is frequency divided at different phase angles by the frequency dividers 1001(1) through 1001(N) to supply the desired sampling pulses to the samplers 1003(1) through 1003(N).
It is also possible to generate the sampling pulse having the frequency equal to 1/LT (L<N) to generate the signal sampled in N different phases by means of interpolation and the like of the received signal sequence sampled in L different phases.
The signals sampled by the samplers 13(1) through 13(N) are supplied to the branch metric calculation circuit 14 to obtain the branch metric. The branch metric circuit 14 may be constructed, for example, as shown in FIG. 5. The outputs from the samplers 13(1) through 13(N) are supplied to the input terminals 50(1) through 50(N). The outputs to the input terminals 50(1) through 50(N) are applied to both of the channel impulse response estimation circuits 51(1) through 51(N) and the partial branch metric calculation circuits 52(1) through 52(N).
Each of the channel impulse response estimation circuits 51(1) through 51(N) may comprise a circuit to obtain correlation between the received signal and the preamble sequence as illustrated, for example, in FIG. 3 of European patent laid-open number A2-0396101 (laid open on Nov. 7, 1990) when using the preamble sequence exhibiting an impulse form of self-correlation function as shown in FIG. 2, for example, in the above European patent application. The channel impulse response estimation circuits 51(1) through 51(N) output channel impulse response vectors H(1) through H(N) of different sampling phases from the signals sampled in different phases. Each of the partial branch metric calculation circuits 52(1) through 52(N) receive as inputs the channel impulse response vectors H(1) through H(N) of different phases and the signal sampled in the phase corresponding to the sampling phase of the channel impulse response vector to calculate the partial branch metric. The partial branch metric will be obtained in the manner as given, for example, in the right member of the equation in J. F. Hayes, "The Viterbi Algorithm Applied to Digital Data Transmission" IEEE, Communication Society, No. 13, p 18, 8b, 1975. The output from the partial branch metric calculation circuits 52(1) through 52(N) are added to one another in an adder 53 to output the branch metric from the output terminal 54.
The calculated branch metric is applied to the Viterbi processor 15 to derive the decision result from the output terminal 16. The Viterbi processor 15 may be realized by a normal soft decision Viterbi decoder comprising an ACS (Add-Compare-Select) circuit and a path memory (See, for example, Suzuki and Tajima, "Implementation of Maximum Likelihood Decoder for Convolutional Codes" Electronic Information Communication Institute Report A, Vol. J73-A, No. 2, pp 225-231, February 1990).
This system can be easily applied to the diversity reception system having a plurality of branches. That is, each diversity branch is provided with a bank of delay circuits 11(1) through 11(N-1), a pulse generator (12), samplers 13(1) through 13(N) and a branch metric calculation circuit 14. The output from the branch metric calculation circuit in each diversity branch is composed by, for example, summation, thereby applying the composed value to the Viterbl processor as the branch metric of the entire diversity.
Illustrated in FIG. 2 is a block diagram of one embodiment of the maximum likelihood sequence estimation apparatus according to a second invention. In FIG. 2, represented by a reference numeral 100 is an input terminal, 101(1) through 101(N) are pulse generators for generating sampling pulses at the frequency (1/T) equal to the symbol rate but in different phases, 102(1) through 102(N) are A-D (analog-to-digital) converters, 103(1) through 103(N) are channel impulse response estimation circuits, 104(1) through 104(N) are branch metric calculator circuits, 105 is a branch metric composite circuit, 106 is a Viterbi processor, and 107 is an output terminal.
The input signal received at the input terminal 100 is sampled and digitized by the A-D converters 102(1) through 102(N) at the timing of the respective pulses of different phases generated from the pulse generators 101(1) through 101(N). The outputs from the A-D converters 102(1) through 102(N) are applied to the channel impulse response estimation circuits 103(1) through 103(N) and the branch metric calculation circuits 104(1) through 104(N) o
Each of the channel impulse response estimation circuits 103(1) through 103(N) may comprise a circuit to obtain correlation between the received signal and the preamble sequence as illustrated, for example, in FIG. 3 of European patent laid-open number A2-0396101 (laid open on Nov. 7, 1990) when using the preamble sequence exhibiting an impulse form of self-correlation function as shown in Fig. 2, for example, in the above European patent application. The channel impulse response estimation circuits 103(1) through 103(N) output channel impulse response vectors H(1) through H(N) of different sampling phases from the signals sampled in different phases. Each of the partial branch metric calculation circuits 104(1) through 104(N) receive as inputs the channel impulse response vectors H(1) through H(N) of different phases and the signal sampled in the phase corresponding to the sampling phase of the channel impulse response vector to calculate the partial branch metric. The partial branch metric will be obtained in the manner as given, for example, in the right member of the equation in J. F. Hayes, "The Viterbi Algorithm Applied to Digital Data Transmission" IEEE, Communication Society, No. 13, p 18, 8b, 1975.
The branch metric composite circuit 105 composites the branch metrics corresponding to the received signals of different sampling phases obtained from the branch metric calculation circuits 104(1) through 104(N), thereby outputting the composite branch metric. The branch metric composite circuit 105 may be configured, for example, as shown in FIG. 6. In FIG. 6, applied to the input terminals 600(1) through 600(N) are the branch metrics corresponding to the received signals of different sampling phases derived from the branch metric calculation circuits 104(1) through 104(N). The added output is derived from the output terminal 602 as the composite branch metric. The composite branch metric thus derived is applied to the Viterbi processor 106 and the decision result is derived from the output terminal 107.
The Viterbi processor 15 may be realized by a normal soft decision Viterbi decoder comprising an ACS (Add-Compare-Select) circuit and a path memory (See, for example, Suzuki and Tajima, "Implementation of Maximum Likelihood Decoder for Convolutional Codes" Electronic Information Communication Institute Report A, Vol. J73-A, No. 2, pp 225-231, February 1990).
Shown in FIG. 3 is a block diagram of one embodiment of the maximum likelihood sequence estimation apparatus according to a third invention. In FIG. 3, represented by a reference numeral 200 is an input terminal, 201 is a pulse generator circuit to generate a sampling pulse at frequency (1/T) equal to the symbol rate, 202(1) through 202(N) are A--D converters, 203(0) through 203(N-1) are delay circuits to provide respectively delay time iT/N (i=1, 2, . . . , N-1), 204(1) through 204(N) are channel impulse response estimation circuits, 205(1) through 205(N) are branch metric calculation circuits, 206 is a branch metric composite circuit, 207 is a Viterbi processor, and 208 is an output terminal.
The sampling pulse generated by the pulse generator circuit 201 is directly applied to the A-D converter 202(1) and also applied to the A-D converters 202(2) through 202(N) by way of the delay circuits 203(0) through 203(N-1). Sampling of the received signal supplied from the input terminal 200 is performed in the A-D converters 202(1) through 202(N) whenever the sampling pulse is applied thereto for digitizing the received signal. The outputs from the A-D converters 202(1) through 202(N) are supplied to the respective channel impulse response estimation circuits 204(1) through 204(N) and branch metric calculation circuits 205(1) through 205(N). Each of the channel impulse response estimation circuits 204(1) through 204(N) receives as inputs the decision result from the Viterbi processor 207 and the output from the respective A-D converters 202(1) through 202(N) for outputting the M dimensional channel impulse response estimation vectors H(1) through H(N) corresponding to the respective output from the A-D converter circuits 202(1) through 202(N). Each of the channel impulse response estimation circuits 204(1) through 204(N) may be implemented, for example, as shown in FIG. 7.
In FIG. 7, applied to the input terminal 700 is the decision result from the Viterbi processor 207 while applied to the input terminal 701 is the output from the respective A-D converters 202(1) through 202(N). A replica of the received signal is obtained by convolution of the decision result and the M dimensional channel impulse response estimation vectors H(i), i=1, 2, ..., N using an M-tapped transversal filter 706. It is to be noted here that any timing error between the replica of the received signal and the actual received signal due to decoding delay time is compensated by delaying the actual received signal from the input terminal 700 using a delay circuit 703 (See, for example, Proakis, "Digital Communications", McGraw-Hill, 1983.) A subtraction circuit 704 detects an error between the output from the delay circuit 703 and the output from an adder 702. An adaptive control processor 705 sequentially updates the channel impulse response estimation vector H(i) in such a manner that the replica of the received signal is equal to the actual received signal. An example of the adaptive control processor 705 is an LSM algorithm (as described, for example, in Proakis, "Digital Communications", McGraw-Hill, 1983) to perform the following mathematical expression (1):
H(i)k+1=H(i)k+,δε(k)S(k) (1)
where, S(k) is the input to the delay circuit 708(1) and the output signal vectors from the delay circuits 708(1) through 708(M+1) at time k or the vector comprising decision results obtained from the time (k-(M-1))T to the time kT, ε(k) is an error signal derived from the subtraction circuit 704 at time k, and H(i) is the channel impulse response estimation vector. In accordance with the above algorithm, H(i)k is updated to output from the output terminals 707(1) through 707(M). Other algorithms may be applied as well.
Each of the branch metric calculation circuits 205(1) through 205(N), the branch metric composite circuit 206 and the Viterbi processor may be similar configuration to 104 (1) through 104(N), 105 and 106 in FIG. 2, respectively.
Now, illustrated in FIG. 4 is a block diagram of an embodiment of the maximum likelihood sequence estimation apparatus in accordance with a fourth invention. In FIG. 4, represented by a reference numeral 300 is an input terminal, 301 is a pulse generator to generate the sampling pulse of the frequency (1/T) equal to the symbol rate, 302 (1) through 302(N) are A-D converters, 303(0) through 303 (N-1) are delay circuits to provide delay times it/N (i =1, 2, . . . , N-1), 304(1) through 304(N) are channel impulse response estimation circuits, 305(1) through 305(N) are branch metric calculation circuits, 306 is a branch metric composite circuit, 307 is a Viterbi processor, and 308 is an output terminal. The pulse generator circuit 301, the A-D converters 302(1) through 302(N), the delay circuits 303(0) through 303(N-1), the branch metric calculation circuits 305(1) through 305(N), and the Viterbi processor 307 may be configured similarly to the pulse generator circuit 201, the A-D converters 202(1) through 202(N), the delay circuits 203(0) through 203(N-1), the branch metric calculation circuits 205(1) through 205(N), and the Viterbi processor 207 in FIG. 3, respectively. Each of the channel impulse response estimation circuits 304(1) through 304(N) may be configured as illustrated in FIG. 8.
In FIG. 8, represented by reference numerals 800 and 801 are input terminals, 802 is an adder, 803 is a delay circuit, 804 is a subtraction circuit, 805 is an adaptive control processor, 806 is an M-tapped transversal filter, 807(1) through 807(54) and 810 are output terminals, 808(1) through 808(M-1) are delay circuits, and 809(1) through 809(54) are multiplier circuits. The difference between the channel impulse response estimation circuits in FIGS. 7 and 8 is that the output from the subtraction circuit 704 in FIG. 7 is applied only to the adaptive control processor 705 while the output from the subtraction circuit 804 in FIG. 8 is applied not only to the adaptive control processor 805 but also to the output terminal 810 as estimation process information. Also, the branch metric composite circuit 306 receives as inputs the branch metrics corresponding to the receive d signals of different phases derived from the branch metric calculation circuits 305(1) through 305(N) as well as the estimation process information derived from the channel impulse response estimation circuits 304(1) through 304(N) for outputting the composite branch metric.
The branch metric composite circuit 306 may be configured, for example, as illustrated in FIG. 9. In FIG. 9, represented by reference numerals 900(1) through 900(N) and 901(1) through 901(N) are input terminals, 902(1) through 902(N) are power detection circuits, 903(1) through 903(N) are comparator circuits, 904(1) through 904(N) are gate circuits, 905 is an adder, and 906 is an output terminal. In FIG. 9, applied to the input terminals 900(1) through 900(N) are the signals on the output terminals (810) from the channel impulse response estimation circuits 304(1) through 304(N) constituting the channel impulse response estimation circuit in FIG. 8. Also, applied to the input terminals 901(1) through 901(N) are the branch metrics derived from the branch metric calculation circuits 305(1) through 305(N) corresponding to the channel impulse response estimation circuits 304(1) through 304(N).
The power detection circuits 902(1) through 902(N) detect the signal power from the respective input terminals 900(1) through 900(N) for application to the comparator circuits 903(1) through 903(N). Each of the comparator circuits 903(1) through 903(N) compares the input level with a predetermined threshold level to output either "1" or "0" if the input level is larger or smaller than the threshold level, respectively. Such comparison output is applied to the gate circuits 904(1) through 904(N). Each of the gate circuits 904(1) through 904(N) disturbs the signal from the input terminals 901(1) through 901(N) when the input from the respective comparator circuits 903(1) through 903(N) is "1", but allows the signal from the input terminals 901(1) through 901(N) to pass when the input from the comparator circuits 903(1) through 903(N) is "0". The adder 905 adds only the branch metrics selected by the gate circuits 904(1) through 904(N) to output the composite branch metric from the output terminal 906. Hysteresis may be provided to the gate circuits 904(1) through 904(N) so that the signal is kept disturbed until the gate circuits are reset if "1" is entered once. It is also possible to apply to the input terminals 900(1) through 900(N) of the branch metric composite circuit 306 the current channel impulse response estimation vectors H(i)K (i=1, 2, . . . , N) for weighting the inputs from the input terminals 901(1) through 901(N) in accordance with H(i)K (i=1, 2, . . . , N), thereby obtaining the similar effect to the maximum ratio composite diversity as described, for example, in S. Stain, J. J. Jones, translated by Hideo Seki, "Modern Communication Circuit Theory", Morikita Publishing Co., 1970.
In case of applying the present invention to the burst mode transmission such as TDMA and the like, it is also possible to process the received signal after storing one burst length of outputs from the samplers 13(1) through 13(N) in FIG. 1. The constructions as illustrated in FIGS. 2 through 4 are easily applicable to such system.
As apparent from the above description, the present invention eliminates distortions due to sampling timing error from the optimum sampling timing and inter symbol interferences in a case of transmitting data by way of channels causing inter symbol interferences. | A maximum likelihood sequence estimation apparatus decodes a digital data signal. The apparatus includes: a sampling device to perform sampling and to output a received signal by sampling pulses having a constant time interval T and N different sampling phases; an operation device to operate a branch metric of the received signal sampled by the N different sampling phases; and a device to perform maximum likelihood sequence estimation of the branch metric. | 7 |
FIELD OF THE INVENTION
The present invention is directed to pharmaceutical compositions containing the protein human tissue plasminogen activator (t-PA) and to methods for making and using such compositions. More particularly, this invention relates to such pharmaceutical compositions having increased stability and solubility characteristics for the t-PA component, and those affording ready lyophilizability, making possible the ability to create stable, lyophilized forms thereof for safe, effective therapeutic administration to human subjects.
BACKGROUND OF THE INVENTION
The instability of vascular plasminogen activator extracted from the vascular trees of human cadavers is described by Aoki, J. Biol. Chem. (Tokyo), 75, 731 (1974). Aoki found that the activator was stabilized only by high sodium chloride concentrations, greater than about 0.5M.
Binder, et al. J. Biol. Chem. 254, 1998 (1979) describe the use of high salt and arginine containing buffer during a multi-step purification procedure as essential to maintain the activity of vascular plasminogen activator derived from human cadaver perfusates. The purification steps where carried out in the presence of 0.3 to 1.0M NaCl and 0.1M arginine.
Radcliffe et al., Arch. of Biochem. & Biophy. 189, 185 (1978) describe the separation of plasminogen activator from human plasma by chromatography on lysine-Sepharose. In one experiment, crude plasminogen activator from stabilized plasma was eluted from lysine-Sepharose using a gradient of 0M to 0.5M arginine in 0.6M NaCl.
Human tissue plasminogen activator derived from natural tissue source is described by Collen et al. in European Patent Application Publication No. 041766, published Dec. 16, 1981 based upon a first filing of June 11, 1980. The authors employed a purification scheme that affords tissue plasminogen activator at relatively high purity levels. Collen et al. studied the stability of preparations of their purified tissue plasminogen activator both in the liquid and lyophilized states, and found that the lyophilized forms were repeatedly unstable even when prepared from solutions containing 0.3M NaCl.
In order that materials like tissue plasminogen activator be provided to health care personnel and patients, these materials must be prepared as pharmaceutical compositions. Such compositions must be stable for appropriate periods of time, must be acceptable in their own right for administration to humans, and must be readily manufacturable. An example of such a composition would be a solution designed for parenteral administration. Although in many cases pharmaceutical solution formulations are provided in liquid form, appropriate for immediate use, such parenteral formulations may also be provided in frozen or in lyophilized form. In the former case, the composition must be thawed prior to use. The latter form is often used to enhance the stability of the medicinal agent contained in the composition under a wider variety of storage conditions, as it is recognized by those skilled in the art that lyophilized preparations are generally more stable than their liquid counterparts. Such lyophilized preparations are reconstituted prior to use by the addition of suitable pharmaceutically acceptable diluent(s), such as sterile water for injection or sterile physiological saline solution, and the like.
SUMMARY OF THE INVENTION
It is an object of the present invention to prepare stable compositions of human tissue plasminogen activator, particularly those in stable, lyophilized form.
The present invention is based upon the discovery that the inclusion of arginine (as arginium ion) in a pharmaceutically acceptable composition of tissue plasminogen activator (t-PA) significantly increases the stability and solubility of t-PA, and further, together with a choice of suitable counterions, makes possible the preparation of stable, lyophilized forms thereof. The invention is thus directed to such compositions and to all associated equivalents and to means to effectively produce such compositions and equivalents.
In general, the compositions may contain other components in amounts preferably not detracting from the preparation of stable, lyophilizable forms and in amounts suitable for effective, safe pharmaceutical administration.
Suitable pH ranges for the preparation of the compositions hereof are from about 4 to about 9, preferably, as these compositions are designed for pharmaceuticals, in the physiological pH span, i.e., about neutral. In this pH range arginine exists primarily as a protonated cation with net charge +1, which can be termed "argininium ion". The term "arginine" is used interchangeably herein with "argininium ion" because due to pH of system, "argininium ion" is an equivalent description. To retain electrical neutrality, the argininium ion must be balanced by an equivalent amount of oppositely charged (i.e. negatively charged) ionic species, which can be termed "counterions". The combination of argininium ion, other cationic species, and the various counterions can be termed an "argininium ion-containing buffer system". Acceptable counterions include those that are pharmaceutically acceptable and additionally those that are capable of adjusting the apparent eutectic or collapse temperature of the composition such that the composition is particularly suited for ready lyophilization. Examples of such counterions are acetate, phosphate, citrate, succinate, sulfate, tartrate, malate, maleate, carbonate, and the like, as well as functional equivalents thereof. An example of a counterion that is not well suited is chloride ion.
As stated above, the inventors have found that inclusion of arginine (as argininium ion) in pharmaceutical compositions of t-PA markedly increases the solubility and stability of the t-PA in these compositions. Arginine concentrations may range from about 0.02M to 1M, preferably from about 0.05M to about 1.0M and more preferably from about 0.1M to about 0.5M in the administered solution, and/or, in the case of a lyophilized preparation, in the prelyophilization solution.
Additionally, the improved compositions may optionally include one or more nonionic detergents, such as polysorbate 20 and polysorbate 80 and the like, in amounts of about 0.001 to about 1 percent, in order to enhance further the stability of the t-PA. In addition, other pharmaceutically acceptable excipients well known to those skilled in the art may also form a part of such compositions. These can include, for example, various bulking agents, additional buffering agents, chelating agents, antioxidants, preservatives, cosolvents, and the like; specific examples of these could include mannitol, tromethamine salts ("Tris buffer"), disodium edetate, gelatin, human serum albumin or other polypeptides, various small peptides such as glycylglycine, and so forth.
The t-PA compositions of the present invention surprisingly do not require the use of high concentrations of sodium chloride, i.e., about 0.3M or above. In fact, high concentrations of chloride ion are detrimental to the lyophilizability of these improved compositions. Although some amount of chloride ion is tolerated, low concentrations are preferred, e.g., less than about 0.3M and are preferably not greater than normal physiological levels i.e., about 0.12M NaCl. Most preferably, chloride ion is excluded from the composition.
A "pharmaceutically effective amount" of t-PA refers to that amount which provides therapeutic effect in various administration regimens. The composition hereof may be prepared containing amounts of t-PA at least about 0.1 mg/ml, upwards of about 50 mg/ml, preferably from about 0.4 mg/ml to about 5 mg/ml. For use of these compositions in administration to human patients suffering from myocardial infarctions, for example, these compositions may contain from about 0.4 mg/ml to about 3 mg/ml t-PA, corresponding to the currently contemplated dosage rate for such treatment.
The compositions hereof including lyophilized forms, are prepared in general by compounding the components using generally available pharmaceutical compounding techniques, known per se. Likewise, standard lyophilization procedures and equipment well-known in the art are employed. A particular method for preparing a pharmacuetical composition of t-PA hereof comprises employing purified (according to any standard protein purification scheme) t-PA in any one of several known buffer exchange methods, such as gel filtration. This preferred method was used to isolate and purify the t-PA used as starting material in the stability and solubility studies which follow. The t-PA used in the preferred method was obtained from recombinantly altered Chinese Hamster Ovary Cells (CHO cells) capable of expressing t-PA as a secreted product in the CHO cell culture medium.
DETAILED DESCRIPTION
Applicants have discovered the demonstrative effect that pharmaceutical compositions of t-PA have significantly stabilized biological activity when argininium ion containing buffer is a component and that such formulations do not require sodium chloride for stability, although salt concentrations lower than 0.3M may be employed. In a preferred embodiment, the chloride ion concentration is 0.1M or less. In the neutral pH range, e.g., about pH 6 to 8, the solubility of t-PA is increased by presence of argininium ion such that it is subject to formulation in relatively high concentrations, even without the presence of what the art has regarded as necessary, high stabilizing amounts of salt.
As used herein, the terms "human tissue plasminogen activator", "human t-PA" or "t-PA" denotes human extrinsic (tissue type) plasminogen activator, produced, for example, from natural source extraction and purification (see Collen et al., supra.), and by recombinant cell culture systems as described herein. Its sequence and characteristics are set forth, for example, in European Patent Application Publn. No. 93619, (published 9 Nov. 1983) based upon a first filing on 5 May 1982, incorporated herein by reference. See also European Patent Application Publication No. 41766 (published 16 Dec. 1981) based upon a first filing of 11 June 80 and Rijken et al. Journal of Biol. Chem. 256, 7035 (1981), also incorporated herein by reference. The terms likewise cover biologically active human tissue plasminogen activator equivalents, differing in one or more amino acid(s) in the overall sequence, or in glycosylation patterns, which are thought to be dependent on the specific culture conditions used and the nature of the host from which the tissue plasminogen activator is obtained.
A. Figures
FIG. 1 depicts the stability of t-PA in various formulations.
FIG. 2 depicts the effect of arginine concentration on the solubility of t-PA.
FIG. 3 depicts the solubility limits of t-PA in various concentrations of argininium phosphate buffers at pH6, 4° C.
B. Lyophilization
Lyophilization, or freeze-drying, of the composition is carried out using procedures and equipment well-known to those skilled in the art. Typically, a composition is first frozen to a temperature below its apparent eutectic or collapse temperature. Vacuum is then applied, and heat applied to the lyophilizer shelves, in order to drive off the ice by sublimation, with shelf temperature and chamber pressure adjusted such that the temperature of the frozen mass remains below the apparent eutectic or collapse temperature until essentially all the ice is removed. Following this "primary drying" phase, the shelf temperature may be raised further (with or without a change in chamber pressure) and residual moisture in the freeze-dried cake is driven off.
C. S-2288 Assay
A synthetic peptide substrate, S-2288 (H-D-Ile-Pro-Arg-p-nitroanilide.2HCl) is hydrolyzed by t-PA forming colored p-nitroaniline and tripeptide. The maximum differential absorbance between substrate and product (p-nitroaniline) occurs at 405 nm. Production of p-nitroaniline is monitored spectrophotometrically by following absorbance at 405 nm as a function of time. The resulting slope of absorbance versus time is proportional to t-PA activity. This assay is run at 37°±0.2° C.
For this assay, 20-100 microliters of a given t-PA sample was added to a 1.2 mL reaction mixture containing 0.33 mM S-2288, 0.067M Tris buffer (pH7.4), 0.07M NaCl and incubated at 37° C. for 10 minutes.
The change in absorbance was monitored for 1 minute and the activity was calculated from the absorbance at 405 nm using the following equation, standardized by the manufacturer: ##EQU1##
D EXAMPLES
Example 1
Purified t-PA was diluted to give a final concentration of 0.2 mg/ml, aliquoted and dialyzed against the buffers shown in Table 1.
TABLE 1______________________________________ Dialysis ConcentrationDialysis Buffer containing Arginine0.01% Polysorbate 80 NaCl (as hydrochloride)______________________________________1. 0.01 M Sodium Phosphate pH 6, -- --2. 0.01 M Sodium Phosphate pH 6, 0.12 M 0.2 M3. 0.01 M Sodium Phosphate pH 6, -- 0.2 M4. 0.01 M Sodium Acetate pH 5, -- --5. 0.01 M Sodium Acetate pH 5, 0.12 M 0.2 M6. 0.01 M Sodium Acetate pH 5, -- 0.2 M______________________________________
After dialysis, the samples were centrifuged and the supernatant lyophilized in 1 ml aliquotes. Lyophilized samples were reconstituted with water and assayed for t-PA activity in the S-2288 assay. Each reconstituted sample was thereafter placed at 37° C. and assayed at various times.
The results of this experiment are shown in FIG. 1. As can be seen, those systems not containing arginine do not prevent the loss of t-PA activity with time. t-PA activity in those samples containing 0.2M arginine, or 0.2M arginine plus physiological amounts of chloride, retain almost all of the initial t-PA activity after incubation for 4 days at 37° C. These results demonstrate that 0.2M arginine with or without NaCl significantly stabilizes t-PA.
Example 2
The stability of t-PA as a function of arginine concentration was determined by measuring the rate of loss of t-PA activity at various temperatures.
______________________________________Formulation: 1. 0.355 mgs/ml t-PA 0.05 M Na phosphate pH 6.2 0.05 M Arginine as the hydrochloride 2. 0.498 mgs/ml t-PA 0.03 M Na phosphate pH 6.2 0.2 M Arginine as the hydrochloride______________________________________
0.5 ml aliquots of solution with the above formulations were aseptically filled into 2 ml glass vials and sealed. The vials were placed at 25°, 37°, 45° C. Two vials of each solution were sampled at 0, 20, 55, and 160 days; and t-PA activity was measured using the s2288 assay. The natural log of the % remaining activity was plotted versus time (days) for each temperature, from which the rate constant was calculated using linear regression analysis.
The rate constants (k) for loss of t-PA stability at two different arginine concentrations and at various temperatures are shown in Table 2.
TABLE 2______________________________________Effect of Arginine on t-PA Stability k (day.sup.-1)Formulation Arginine 25° C. 37° C. 45° C.______________________________________0.05 M 0.05 M 0.00137 0.0102 0.0167NaPhosphate, pH 6.20.03 M 0.20 M 0.00043 0.00569 0.01272NaPhosphate, pH 6.2______________________________________
As can be seen, 0.2M arginine produces rate constants which are smaller than those obtained in 0.05M arginine at each of the indicated temperatures indicating that an increase in arginine concentration increases the stability of t-PA.
Example 3
The stability of t-PA is also dependent upon the concentration of non-ionic surfactants. The data are in Table 3.
t-PA was precipitated by dialysis versus 0.01M Na succinate buffer at pH6.0. The t-PA precipitate was collected from the dialyzed sample by centrifugation. This precipitate was redissolved in the formulation below containing varying concentrations of polysorbate 80.
______________________________________Formulation: 0.2 M Arginine as the hydrochloride 0.02 M Na phosphate pH 7.2 Polysorbate 80 (0.0005 to 0.10 percent)______________________________________
The solutions were aseptically filled into vials and placed at 35° C. and 40° C. Two vials were sampled at each time point and enzymatic activity was assayed using the S2288 assay.
The rate constants were calculated by linear regression analyses of the 10 g (t-PA activity) versus time curve for each temperature, and are shown in Table 3.
TABLE 3______________________________________Effect of Polysorbate 80 on t-PA StabilityPolysorbate 80 k (day.sup.-1)% 35° C. 40° C.______________________________________0.0005 .0055 .01060.005 .0049 .00910.01 .0043 .00880.025 .0040 .00810.05 .0041 .00770.10 .0037 .0075______________________________________
This table demonstrates that as the concentration of polysorbate 80 is increased the rate constant (k) decreases. This indicates that more stability is achieved with more polysorbate 80.
Example 4
t-PA solutions were prepared by dialysis of purified t-PA versus the agininium phosphate formulation buffer below, followed by dilution with further buffer to the desired final concentration of t-PA.
______________________________________Formulation buffer:______________________________________ 0.20 M Arginine 0.18 M Phosphoric acid 0.01% Polysorbate 80 pH 6______________________________________
Aliquots of each preparation were aseptically filled into 5 or 10 mL vials, lyophilized and sealed. Vials were placed at several temperatures. Two vials per formulation were sampled at each time point and t-PA activity determined by the S2288 assay. The results are in Table 4.
TABLE 4__________________________________________________________________________Stability of t-PA in Lyophilized Formulation % Remaining (mean of 2 assays ±t-PA Time standard deviation)(mg/ml)*pH (mo) 5° C. 25° C. 30° C. 35° C. 40° C.__________________________________________________________________________1.0 6.0 2.0 102.5 ± 0.0 103.3 ± 2.5 -- 102.6 ± 3.0 --2.0 6.0 2.0 111.3 ± 0.7 111.1 ± 0.1 -- 114.6 ± 2.2 --5.0 6.0 2.0 112.0 ± 0.3 112.7 ± 0.6 -- 112.3 ± 1.4 --1.0 6.0 3.5 98.2 ± 1.3 -- 96.0 ± 1.7 -- 97.7 ± 00.1__________________________________________________________________________ *Concentration of tPA in solution prior to lyophilization
This data demonstrates that t-PA is stable in the lyophilized form.
Example 5
A solution containing t-PA at approximately 0.3 to 0.5 mg/ml was dialysed against 10 mM sodium phosphate, pH 7.5, 0.01% polysorbate 80 containing various concentrations of arginine as the hydrochloride. Insoluble material was removed by centrifugation for 2 minutes in an Eppendorf microfuge. The amount of t-PA which remained in solution was assayed in the S-2288 assay. Results are shown in FIG. 2.
As little as 50 mM arginine significantly increases the solubility of t-PA. (The smaller increase in apparent solubility at higher arginine concentrations is an artifact, due to the fact that the original concentration of t-PA in the starting material was only 0.3 to 0.5 mg/ml and thus a limiting solubility was never reached.)
Example 6
t-PA was precipitated by dialysis versus 0.001M sodium succinate buffer at pH6. The resulting precipitate was isolated by centrifugation, then a measured amount of this material was equilibrated in 1 ml of the desired buffer system for 20 hours at 5° C. with agitation. The buffer systems studied were prepared by titration of arginine with phosphoric acid to product an argininium phosphate system at pH6.0. Stock solutions were diluted with water to obtain final buffer solutions containing 0.10 to 0.20M arginine (as argininium ion). Following equilibation with the desired buffer system, the resulting t-PA preparation was centrifuged to remove any nonsoluble material, then the supernatants were assayed for soluble t-PA via the S2288 assay.
Results are shown in FIG. 3. If the t-PA is fully soluble at the concentration of t-PA originally added, then the concentration of soluble t-PA should be the same as that added. Conversely, if the t-PA is not fully soluble at the concentration originally added, then the concentration of soluble t-PA will be less than that added. FIG. 3 shows that t-PA is soluble in 100 mM arginine phosphate pH6.0 up to about 2 mg/ml, and that at higher arginine phosphate concentration the solubility is markedly enhanced. In particular, at 200 mM arginine phosphate pH6.0 the t-PA is still fully soluble even at about 54 mg/ml, and clearly the limiting solubility is considerably higher than this.
Example 7
The argininium phosphate system below was prepared as a prelyophilization solution.
______________________________________Prelyophilization Solution mg/ml______________________________________t-PA 2.5L-arginine 87.1Phosphoric Acid 26.8Polysorbate 80 0.1pH 7.2______________________________________
Following sterile filtration, approximately 20 ml aliquots were filled in 50 cc vials. Lyophilization was then carried out as follows:
(a) The vials were placed into the lyophilizer and frozen at -50° C. (shelf temperature) under ambient pressure for 10 hours.
(b) Vacuum was applied (chamber pressure of 100 μm Hg) and the shelf temperature raised at 10°/hr. to +7° C., then held at the temperature for 41 hours.
(c) The shelf temperature was then raised to +35° C. and the chamber pressure lowered to 50 μm, and the system held in this state for 14 hours.
The vials were then stoppered, the pressure allowed to return to ambient, and the vials removed from the lyophilizer.
Example 8
The effect of sodium chloride on the quality of lyophilized arginine phosphate cakes was investigated. Samples of 0.8M arginine (pH 7) and 0.2M arginine (pH 6) as the phoshpate salts were prepared to include concentrations of sodium chloride ranging from 0.01 to 500 mM. 2 mL aliquots of each solution were placed into 10 cc vials and lyophilized using the following cycle:
______________________________________Lyophili-zation Shelf Temperature Chamber Pressure TimeStep (Degrees Centigrade) (Microns) (Hours)______________________________________Freezing -45 Ambient 10Primary Increase at 20° /hr 50 24Drying to -35° , then 3° /hr to +35°Secondary +35 40 26Drying______________________________________
The quality of the resulting cakes are given in Table 5. The data show the formation of pharmaceutically acceptable cakes only with those compositions containing low levels of sodium chloride and that the tolerated low level of sodium chloride is dependent on the arginine concentration.
TABLE 5__________________________________________________________________________Quality of Lyophilized Arginine Buffer System containing SelectedSodium Chloride Concentrations Cake Quality After 2 Months atSodium Chloride Initial Room TemperaturemM 0.8M Arginine 0.2M Arginine 0.8M Arginine 0.2M Arginine__________________________________________________________________________500 Glassy, shrunken Granular, shrunken Same as Initial Same as Initial mass; no cake mass; no cake100 White cake; White cake Same as Initial Glassy film on slight melting on with glassy vial bottom; no cake sides appearance cake50 White cake; White cake Same as Initial Glassy to white glassy edges with glassy mass on vial slightly shrunken appearance bottom10 White cake; White cake Same as Initial White mass in slightly shrunken very much shrunken vial1 White cake; very White cake; very Same as Initial Further slightly shrunken much shrunken shrunken0.1 White cake; very White cake; very Same as Initial Further slightly shrunken much shrunken shrunken0.01 White cake; very White cake; very Same as Initial Slight slightly shrunken much shrunken additional shrinkage__________________________________________________________________________
It will occur to those ordinarily skilled in the art that various modifications may be made to the disclosed embodiments and that such modifications are intended to be within the scope of the present invention. | Disclosed are novel, stable pharmaceutically acceptable compositions containing human tissue plasminogen activator, featuring, for example, an argininum ion containing buffer as a component. Also disclosed are associated means and methods for preparing and using such compositions in various forms. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to microscopes, and is more particularly concerned with the apparatus involved in the focusing of microscopes, including nosepiece support assemblies, adjustment mechanisms, combining coarse and fine adjustment means for manipulation of a nosepiece support assembly, and gear train systems as a component of the adjustment mechanisms.
Microscope adjustment systems commonly provide mechanisms for adjustment of the nosepiece relative to the stage which mechanisms incorporate both coarse and fine adjustment means, in many instances, controlling a shaft-mounted cam associated with linkage components which translate rotational movement of the cam into vertical adjustment of the nosepiece. Examples of such systems will be noted in the following patents:
______________________________________3,135,817 Wrigglesworth et al3,260,157 Boughton3,768,885 Boughton et al______________________________________
SUMMARY OF THE INVENTION
The present invention is concerned with an adjustment system for microscopes which constitutes a significant advance over prior art systems in simplicity of construction, manner of operation and nosepiece adjustment, and most particularly in the ease of access to the operating components for purposes of servicing, repair or replacement.
Briefly, the vernier or fine adjustment utilizes a reduction gear train system including dual parallel gear trains mounted as a unit within a gear box. The gear box, as opposed to conventional microscope construction, mounts externally of the arm assembly on an arm-traversing cam mounting shaft. The cam will be mounted, as is usual, internally within the arm assembly for engagement with the internally positioned nosepiece support assembly.
It is significant that one of the dual gear trains incorporates a compound gear formed of independent reduction and pinion gears with an interposed coiled torsion spring acting to rotationally bias the two gears in opposite directions as a means for preventing backlash within the gear trains and reducing lost motion, thus avoiding the necessity of highly precisioned formed gears. Similarly, the use of a spring loaded compound gear allows for an automatic accommodation of the entire gear train system to a degree of normal wear.
The externally mounted gear box will itself be directly received within the coarse adjustment handwheel which will in effect provide a readily removable housing therefor. The assembly will be completed by an outer vernier adjustment handwheel. Assembled in this manner, access to the gear trains for servicing, replacement, or the like, can be accomplished both simply and rapidly by a sequential removal of the handwheels. There is no longer any necessity for completely disassembling the microscope, changing the nosepiece adjustment, or otherwise disrupting a microscope setup. Ideally, any downtime of the microscope can be substantially completely eliminated by merely having at hand a replacement gear box.
The adjustment system includes a nosepiece support having a horizontal carriage mounted within the microscope arm assembly for vertical guided movement in response to vertical movement of an elongated rigid rod affixed to the carriage. The rod, in turn, is in operative engagement with the cam. The nosepiece support provides for a direct vertical adjustment in response to rotation of the cam and without reliance on interposed pivoting linkages.
Additional objects and advantages of the invention will become apparent from the details of construction and manner of use of the invention as more fully hereinafter described and claimed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a microscope incorporating the features of the present invention, portions thereof being broken away for purposes of illustration;
FIG. 2 is an enlarged transverse sectional view through the coarse and fine adjustment mechanism with the handwheels and gear box outwardly positioned;
FIG. 3 is a top plan view of the microscope with a portion of the top wall of the arm assembly removed;
FIG. 4 is a transverse section taken generally in line 4--4 of FIG. 3;
FIG. 5 is an exploded perspective view of the components of the coarse and fine adjustment mechanism.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring now more specifically to the drawings, reference numeral 2 designates a microscope incorporating the features of the invention. This microscope includes a base 4 with a support arm 6 extending upwardly from the base, the base 4 and support arm 6 combining to form the microscope frame 8. The microscope 2 also will include, mounted to the frame, one or more eyepieces (not illustrated), a nosepiece 10 and a stage 12 therebelow.
The nosepiece 10 is mounted for vertical adjustment through a support or support system 14 received within the support arm 6. This support system 14 includes a horizontal carriage, within a horizontal extension of the support arm, positioned in generally parallel upwardly spaced overlying relation to the base 4. The carriage 16 basically comprises a planar panel member 18 with an upstanding peripheral wall 20 and a reinforcing grid of integral upstanding ribs 22.
A cylindrical boss 24 depends from the outer end portion of the carriage 16 for a telescopic reception of the upper portion of the nosepiece 10 therein. For retention of the nosepiece, it is proposed that an undercut shoulder or dovetail configuration 26 be defined about the boss-received portion of the nosepiece with the boss mounting three selectively adjustable retaining screws 28 engageable within the dovetail, preferably in a manner as to allow for a rotational adjustment and centration of the nosepiece to the optical path.
The second end of the carriage 16, aligned over the vertical portion of the arm assembly 6, includes two vertically directed integral split sleeves 30 and 30A which receive and rigidly clamp to the upper end portion of a vertical rod or shaft 32. The rod 32 depends from the carriage 16 and is rotatably received within a pair of vertically spaced sleeve bearings 34, each mounted within split sleeves 36 integrally formed with an adjoining portion of the frame 8. A block 38 is mounted rigid with the lower end of the rod 32 and in turn mounts a laterally offset cam follower 40 which rides on the upper edge of cam 42 and is retained in following relation thereto by the weight of the support system 14. Pin 44 projecting laterally from block 38 loosely enters groove 46 on the lateral face of cam 42 as a safety precaution, allowing and limiting the amount cam roller 40 can lift off of cam 42 when the downward movement of the carriage 16 is impeded for any reason.
As will be appreciated, the support or support system 14 for the nosepiece 10, responsive to rotation of the cam 42, adjusts or shifts vertically without pivotal movement and as an integral rigid unit as detailed in FIGS. 3 and 4. In order to assist this vertical adjustment and maintain lateral stability for the remote, nosepiece-supporting end of the carriage 16, a pair of opposed guide rollers 48 mount within vertical channels 50 on the opposed walls 52 of the horizontal portion of the support arm assembly. One of rollers 48, noting FIGS. 3 and 4 will normally be spring-loaded, opposing other fixed roller 48, thereby providing a fixed position for the cylindrical portion 24 of the carriage 16 with both rollers 48 engaging against flats 54 on the aligned portions of the carriage 16.
Referring now to FIG. 2, a sectional view is shown of the adjustment mechanism, including cam 42, and its association with the rod 32 of the support system. Attention is also directed to FIG. 5 wherein the components of the adjustment mechanism are detailed. The adjustment system mounts transversely through the support arm 6 and, in particular, between and through opposed mounting plates 56 and 58 in opposed arm walls 60 and 62 respectively.
An elongate quill shaft 64 traverses the support arm and projects outwardly of the opposed wall mounting plates 56 and 58. A relatively shorter cam shaft 66 is received over quill shaft 64 and extends through mounting plate 56. The inner portion of the cam shaft 66 within the support arm assembly mounts the cam 42, locked thereto by appropriate means such as set screw 68. The outer end of cam shaft 66, outward of wall 60 and mounting plate 56, has an integrally formed gear 70 thereon. Two flanged bearings 72 are pressed into opposed ends of the cam shaft 66 and are free to rotate on quill shaft 64. An elongate central shaft 74, defining the gear train system drive shaft, is rotatably received through the quill shaft 64 and projects beyond the opposed outer end portions thereof. Appropriate bushings, as at 76, may be provided. The end portion of the drive shaft 74, beyond wall 60, includes an integral drive pinion 78 immediately outward of the corresponding end of quill shaft 64.
Attention is now directed to the construction illustrated to the left in FIG. 2, at and beyond the wall 60 and mounting plate 56. This construction, detailed in FIG. 5, includes a gear box assembly 80 particularly adapted to mount as a unit on the exposed shaft end portions and in engagement with cam gear 70 and drive gear 78. The gear box asembly 80 includes inner and outer gear box plates 82 and 84, an intermediate spacer block 86 and spacer posts 88 between the block 86 and inner plate 82.
The gear train system comprises dual generally duplicate gear trains including a first pair of compound gears 90, each having a reduction gear 92 adjacent outer gear box plate 84 and an inwardly extending elongate pinion gear 94 which is freely rotatably received through spacer block 86 and extends inwardly thereof. The compound gears 90 mount on elongate shafts, the ends of which are received in the opposed box plates 82 and 84, and are so oriented as to drivingly engage the reduction gears 92 with the drive gear 78 of shaft 74.
Inward of the spacer block 86 is a second pair of compound gears 96, each including a reduction gear 98 meshed with a pinion 94 of a corresponding compound gear 90. The compound gears 96 in turn include integral pinions 100 inwardly directed. Noting the detail of FIG. 5, the outer face of the reduction gear 98 of one of the compound gears 96 is provided with an outwardly directed pin 102 which rotatably aligns with an abutment or abutment pin 104 on and inwardly directed from the inner face of spacer block 86, providing for a rotational limit to the associated compound gear 96, and hence the gears drivingly associated therewith.
The pinion 100, associated with the compound gear 96 incorporating the limit pin 102, meshes with reduction gear 106 of a compound gear 108 which includes an integral pinion gear 110.
A compound gear 112 is provided as a companion to the compound gear 108 and includes reduction and pinion gears 114 and 116 of equal size as gears 106 and 110 respectively and joined by an internal coiled torsion spring 115 therebetween. The two pinion gears 110 and 116 mesh in driving engagement with the cam gear 70 whereby a rotation of the gear box assembly 80 in its entirety will effect a direct or coarse adjustment of the cam shaft 66. On the other hand, operation of the gear trains, through a rotational driving of driveshaft 74, will effect a fine or vernier rotation of the cam pinion 70 and cam shaft 66.
The use of dual gear trains is significant in stabilizing and enhancing the precision of the vernier adjustment. A significant further contribution is derived from the spring loaded compound gear 112 in that the coiled torsion spring 115, acting to resiliently bias the associated gears 114 and 116 in opposite directions, maintains both these two gears, and through them all of the gears of the assembled system, in intimate seated or meshed engagement. This in turn removes any tendency for backlash or lost motion within the gear train system, while at the same time allowing for manufacturing tolerances and avoiding the necessity of the use of high precision formed gears. It will also be recognized that the construction, as proposed, will provide for an automatic accommodation of some degree of system wear.
An inner handwheel 118, for coarse adjustment, is telescopically received over the gear box assembly 80, defining in effect a housing therefor. The gear box assembly 80 is secured to and within the inner handwheel 118 by appropriate threaded fasteners 120 engaged through the inner gear box plate 82 and a plate supporting shoulder or pair of opposed shoulders 122 interiorly of the handwheel 118. The handwheel 118 can include an inwardly directed alignment pin 124 receivable through a guide aperture 126 in the inner mounting plate 82 to provide rotational limits when engaged with two pins 160 mounted outwardly in plate 56. The gear box assembly 80 with the handwheel 118 attached is then secured to the quill shaft 64 with set screws 161. An outer handwheel 128, for fine or vernier adjustment, is secured to the outer end portion of the central driveshaft 74 outward of drive pinion 78. The handwheel 128 is mounted between an outer retaining clip 130 and multiple annular or disc springs 132 engaged between the pinion 78 and the inner face of the vernier handwheel 128. Mounted in this manner, the outer handwheel 128, upon the introduction of a rotational overload, will tend to slip rather than overextend the capability of the gear train.
It will also be noted that the outer handwheel 128 includes an inwardly directed annular flange or skirt 134 which is received within an outwardly directed annular groove 136 about the inner handwheel 118, thus providing for a rotatable mating therebetween in a manner which allows for a rotation of the handwheels independently with each other in conjunction with a retention of the inner handwheel 118 by the outer handwheel 128.
Turning now to the right hand portion of FIG. 2, inner and outer handwheels, 138 and 140 respectively, are provided to duplicate the adjustment capability of the handwheels 118 and 128. The auxiliary inner handwheel 138, for coarse adjustment, is locked to the quill shaft 64 for a direct rotation thereof and the cam shaft 66 therewith. The outer auxiliary handwheel 140, for fine or vernier adjustment, mounts to the inner driveshaft 74 for direct rotation thereof and the gear train system therethrough. The auxiliary outer handwheel 140 is clip and spring mounted in the manner of the handwheel 128. Appropriate annular or disc spring assemblies 142, engaged with the opposed faces of the inner handwheel 138 and incorporating one or more shaft-mounted clips 144, are also present and provide a braking action holding the adjusted position of the inner handwheels 118 and 138 during rotation of the outer handwheels 128 and 140.
In operation, rotation of either or both inner handwheels 118 and 138 effect a direct rotation of the cam shaft 66 and cam 42 for a coarse adjustment of the vertically movable support assembly. It should be appreciated that the cam 42, acting on the follower 40, operates to elevate the nosepiece. Lowering of the nosepiece will normally be effected by the weight of the support assembly itself, as the cam 42 is rotated in the opposite direction.
When fine adjustment of the vertical position of the nosepiece is desired, the inner handwheels 118 and 138 are released and the outer handwheels 128 and 140, individually or together, rotated. Rotation of these handwheels effects a direct rotation of the driveshaft 74 and drive pinion 78. This in turn drives the gear trains within the gear box assembly and, in turn, the cam pinion 70. Rotation of the gear trains will be limited by limit pin 102 engaging abutment 104 to ten turns of the outer handwheels 128 and 140.
As previously indicated, a particularly significant feature of the invention is the ready accessibility of the gear box assembly and gear train system itself for servicing or replacement without necessitating a disassembling of the microscope frame and with little or no interruption. From the above detailed description of the construction involved, it will be appreciated that, basically, upon a removal of the outer retaining clips which retain the outer handwheels 128 and 140, and loosening the set screw 161 in gear box 80, the remaining operating components, including the inner handwheels and gear box assembly, can be easily slipped from the mounting shafts. Similarly, the central driveshaft 74 itself can be easily withdrawn. Should the gear box assembly or gear trains require servicing, a substitute assembly can be quickly slid into position, the handwheels remounted and the entire apparatus put back into service with only a few moments delay and no appreciable downtime. The gear box assembly is self-contained and, through the torsion loaded nature of one of the compound gears, readily engaged in operative relationship with the cam gear 70.
The foregoing description of an embodiment of this invention is given by way of illustration and not of limitation. The concept and scope of the invention are limited only by the following claims and equivalents thereof which may occur to others skilled in the art. | In a microscope, a nosepiece support assembly and a coarse and fine adjustment mechanism in direct operative control of the support assembly, the support assembly including a nosepiece mounting carriage with a depending rod rigid therewith and mounting a cam follower which rides on the edge of a cam, rotation of which is controlled by the adjustment mechanism. The adjustment mechanism in turn includes a reduction gear assembly utilizing dual gear trains and mounted to a cam-mounting shaft externally of the frame of the microscope and housed within a coarse adjustment handwheel for immediate access thereto. One of the gear trains incorporates a compound gear having a torsion spring between the individual gears to enhance gear train interengagement throughout the gear assembly. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the invention
The present invention relates to a turbojet aero-engine with a high bypass ratio.
2. Description of the Prior Art
It has been common for some years to use bypass turbojet engines for subsonic propulsion, the advantage of mixing the cold and hot air streams being to increase the thrust of the hot engine.
Nevertheless, in practice, one is restricted as to the by-pass ratios which are possible to employ in such engines because of their frontal area and the large cross section which is the corollary of this. Above a bypass ratio of between 8 and 14, the engines become prohibitively large and are effectively prevented from being mounted below the wings of an aircraft.
If it is desired to exceed a bypass ratio of 8, the solution adopted in conventional turbojet engines with an upstream fan, at least up to a bypass ratio of about 11, is to provide the low pressure turbine with between 5 and 8 stages.
For a bypass ratio of from 11 to 14, the conventional solution is no longer convenient (owing to the need for an excesive number of low pressure turbine stages) and it is necessary to use a reduction gear for the front-mounted fan, or a rear-mounted contrarotating fan driven directly by a contrarotating power turbine with interleaved stages.
Above a bypass ratio of 14, one enters the realm of turbo-jet engines with high speed propellers.
These engines are of interest because of the improvement in specific fuel consumption which they provide, but have the disadvantage, because of their large overall diameter, of being capable of installation only at the rear and on either side of the fuselage of the aircraft, or only with highly-integrated and unconventional underwing installations of the type proposed in, for example, French Patent No. 2 622 507.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a construction which would enable turbojet engines to be made with a bypass ratio of between 8 and 14 while presenting a frontal area very little larger than present day turbojet bypass engines with a bypass ratio of below 6.
It is also an object of the invention to provide such an engine with an increased bypass ratio and thrust without requiring any increase in the total number of stages of blades, which would have an adverse effect on the cost of the engine.
According to the invention there is provided a turbojet engine having a high bypass ratio, said engine including a low pressure unit comprising an upstream fan and a low pressure compressor coupled to said upstream fan, a gas generator comprising a high pressure compressor, a combustion chamber and a high pressure turbine driving said high pressure compressor, a low pressure turbine driven by said gas generator and itself driving said low pressure unit, a rear fan, and a contrarotating turbine interleaved with said low pressure turbine and driving said rear fan.
In a preferred arrangement the upstream fan has a diameter such that the bypass ratio between the cold air flow passing through it and the hot gas flow through the gas generator (i.e. the primary gas flow) is between 6 and 8, whilst the rear fan has a diameter such that the bypass ratio between the cold air flow passing through it and the primary gas flow is between 4 and 6.
In accordance with a further important preferred characteristic of the invention, the engine comprises two imbricated separate flow paths for the cold air. The first cold air flow path passes through the upstream fan and has an air intake in common with the primary airflow to the gas generator, and two crescent shaped outlets are disposed laterally outwardly of the outlet from the rear fan. The second cold air flow path passes through the rear fan and comprises two crescent shaped air intakes disposed laterally outwardly of said intake of said first flow path, and passages leading from said crescent shaped intakes and merging to form an annular passage in which said rear fan is disposed, said annular passage surrounding the hot gas flow from said gas generator and defining an annular outlet from said second flow path.
Preferably the turbojet engine comprises a nacelle having two hinged shells, the passages of said first and second cold air flow paths being formed at least partly within the structure of said nacelle.
This structure enables the nacelle to be given a generally oval shape with a cross section in the form of an ellipse having its major axis horizontal, thus permitting the engine to be mounted beneath the wing of an aircraft having a ground clearance sufficient only for a conventional engine with a much smaller bypass ratio.
The invention thus allows a high bypass ratio turbojet engine to be produced with a low overall size and cross-section which will permit the mounting of the engine beneath the wing of an aircraft.
Other preferred features of the invention will become apparent from the following description, with reference to the drawings, of one embodiment of a turbojet engine in accordance with the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:
FIG. 1 is a partial longitudinal section of one embodiment of a turbojet engine in accordance with the invention.
FIGS. 2a and 2b show diagrams of the cold air flow paths, the paths being shown separated from each other for the sake of simplicity. FIG. 2a shows the first cold air flow path through the upstream fan of the engine, and FIG. 2b shows the second cold air flow path through the downstream fan.
FIG. 3 is a three quarters rear perspective view of the turbojet engine fitted into its nacelle and suspended from a wing-mounted pylon.
FIG. 4 is a view similar to that of FIG. 3 showing the engine in the reverse thrust position in which the two flaps of the thrust reverser are fully deployed.
FIG. 5 is a similar view to that of FIG. 3 showing one of the nacelle shells hinged upwards to provide access to the engine.
FIGS. 6A to 6G show cross sections through the engine nacelle with its shells closed and taken in planes A to G respectively in FIG. 5.
FIG. 7 is a perspective view of an aircraft showing an engine in accordance with the invention mounted under a wing of the aircraft.
DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to FIG. 1, the engine shown incorporates, in a conventional manner, an upstream fan 1 coupled to a low pressure compressor 2, followed by a high pressure compressor 3, a combustion chamber 4, a single-stage high pressure turbine 5 which drives the high pressure compressor, and a low pressure turbine 6 with four stages which drives the low pressure components 1 and 2.
In accordance with the invention, the engine comprises a downstream contrarotating turbine 7 here represented, by way of example, as having two stages 7a and 7b. However, taking into account the bypass ratios hereinafter stated and the sizing of the upstream and downstream fans, a four-stage turbine will generally be preferred.
The disc 8 of the turbine is carried on a shaft 9 mounted inside the low pressure turbine shaft by means of two bearings 10, and the stages 7a and 7b of the turbine are coupled by means of the outer casing 11 which rotates with them. The assembly carries a rear fan 12 of large diameter generating a bypass ratio of 5 (this value is not limiting), whereas in this example the bypass ratio of the upstream fan is 7 (also a non-limiting value).
The two fans 1 and 12 are therefore "in parallel" and rotate at different speeds.
The engine is suspended from a wing-mounted mast 30 by an upstream pylon 13 fixed to structural members 14 and by a downstream pylon 15 rigid with the engine housing in the region of the housing struts which serve as the flow straighteners 16 for the high Pressure turbine.
In FIG. 1, it is indicated diagrammatically that the two fans are supplied by separate air flow paths. The first flow Path comprises an annular air intake El which will be described further below, and an air outlet S1 in the form of two crescents also described below. The second flow path comprises an air intake E2 in the form of two laterally disposed crescents which will be described further below, and an annular air outlet S2 surrounding the hot gas flow 17.
In FIGS. 3 and 4, the engine is shown fitted into a nacelle 18 and is viewed from a three quarters rear position. The nacelle comprises a flow-reversing mechanism 19 with two flaps, which in fact form the exhaust flow nozzle of the first cold air flow path. On pivoting, the flaps intercept the whole flow coming from the upstream fan in the first flow path, and also a part of the flow from the downstream fan in the second flow path, as is also shown in FIG. 6G.
The nacelle is formed with two lateral shells 20 pivotally mounted about longitudinal axes, one on each side of the supporting mast.
FIG. 5 shows the nacelle with one of its lateral shells 20 raised to provide access to the engine. As can be seen from the inside of the raised shell, the cold air flow paths are formed largely within the structure of the shells. Thus, it is the nacelle that ensures the arrangement of the two air flow paths.
The latter are shown diagrammatically in FIGS. 2a and 2b. FIG. 2a shows the first air flow path which includes the upstream fan. The annular air intake El is conventional and is common to that for the combustion air flow. Downstream of the fan 1, the flow path splits into two passages, one 21 above the engine and the other 22 beneath the engine. In the upstream part of the passages 21 and 22 there are provided two vertical through-wells 23a and 24 respectively, the well 23a in the passage 21 accommodating the upstream suspension pylon 13 and accessories, and the well 24 in the passage 22 allowing the passage of a bevel gear train to a gearbox 25 disposed in the lower part of the nacelle.
At its downstream end the upper passage 21 splits into two branches 21a and 21b which diverge laterally and join up with the corresponding branches 22a,22b respectively of the lower passage 22 which also splits at its downstream end into two laterally diverging branches. After the merging of the branches 21a and 22a and the merging of the branches 21b and 22b, each of the passages thus formed has the appearance of a vertical crescent 25a,25b, and together form the air outlet S1 of the upstream fan.
FIG. 2b shows the second cold air flow path which includes the downstream fan 12. At the upstream end, the air intake E2 is formed by the two vertical crescent shaped passages 26a,26b, which are initially of constant cross section but then adopt a more necked, petal shape before coming together to form an annular passage 27 which surrounds the hot gas flow and supplies the fan 12. Downstream of the fan 12, the passage 27 retains its annular shape.
In practice, the two air flow paths are imbricated, the crescent shaped inlets E2 of the second flow path lying laterally outwards of the annular inlet E1 of the first flow path, the crescent shaped outlets S1 of the first flow path lying laterally outwards of the annular outlet S2 of the second flow path, and the passages 26a,26b of the second flow path passing through the spaces 28a,28b formed between the passages 21,22 of the first flow path as shown in FIG. 2a.
To achieve such an arrangement, the structure of the nacelle is brought into play, as will be described below with reference to FIGS. 6A to 6G.
The nacelle comprises a structural part including a longitudinal beam 29 fixed to the supporting mast 30 and extending the whole length of the nacelle. The beam 29 comprises two lateral edges carrying longitudinal hinges 31 for pivotally mounting the openable lateral shells 20 of the nacelle as mentioned earlier.
As indicated in FIG. 6A, at the upstream end of the nacelle the two shells 20 are wholly occupied by the passages 26a,26b defining the crescent shaped intakes E2 of the second bypass air flow path.
At the position of Section B (FIG. 6B) the beam 29 becomes thinner, forming between itself and the engine the beginning of the upper passage 21 of the first air flow path. The lower part of the nacelle is also structural and defines, in the region of Section B, a seating for the gearbox 25.
At the position of Section C (FIG. 6C), the passages 26a,26b are narrowed so as to become petal-shaped, and the shells 20 have lengthened radial walls 33 connecting the inner wall 20a to the outer wall 20b of the shell. These radial walls 33 separate the passages 26a, 26b from the upper and lower passages 21 and 22 of the first flow path formed respectively between the upper beam 29 and the engine casing 32 and between the casing 32 and the lower structural part 34 of the nacelle.
At the position of Section D (FIG. 6D), the shells 20 no longer possess an inner wall, and the radial walls 33 cooperate with stub walls 35 fixed to the casing 32 to separate the passages 26a,26b from the passages 21 and 22. At this position the upper beam 29 defines a through-well 23b in the channel 21 to accommodate the passage of the rear supporting pylon 15.
At the position of Section E (FIG. 6E), the shells 20 once again have an inner wall 20a, which ensures the separation of the first flow path outlet passages 25a, 25b from the intake passage 27 of the second flow path.
From the position of Section F onwards (FIGS. 6F and 6G), the shells 20 are wholly occupied by the crescent shaped passages 25a, 25b forming the outlet S1 of the first flow path.
In FIG. 6G the dotted lines indicate the position of a flap 19 of the thrust reverser in the deployed position. As can be seen, in the thrust reversal position the whole of the outlet passage S1 of the first flow path (passages 25a and 25b) is closed off, and a part of the passage 27 forming the outlet S2 of the second flow path is also obstructed. Thus, the thrust reverser operates with maximum efficiency by acting on the flow from both fans.
Referring now to FIG. 7, it can be seen that, because of the ovoid form of the nacelle, an engine in accordance with the invention placed under the wing of an aircraft demands a lesser ground clearance for the wing than a conventional circular-section engine with the same by-pass ratio. Alternatively, with the same ground clearance as for conventional engine, one can fit an engine with a higher by-pass ratio provided that it is constructed in accordance with the invention.
Obviously, numerous modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein. | A turbojet bypass engine includes an upstream fan of a conventional type also a downstream fan arranged to rotate in the opposite direction to the upstream fan and driven by a free turbine interleaved with the low pressure turbine which drives the upstream fan. The two fans are supplied by separpate overlapping and inverleaved air flow paths which are formed largely within the nacelle structure of the engine, giving the nacelle an ovoide shape which allows such engines with a high bypass ratio to be mounted below the wings of an aircraft. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. application Ser. No. 14/665,068, which was filed on 23 Mar. 2015. U.S. application Ser. No. 14/665,068 is a divisional of U.S. application Ser. No. 12/826,629, which was filed on 29 Jun. 2010 and has issued as U.S. Pat. No. 9,004,492. U.S. application Ser. No. 12/826,629 is a divisional of U.S. application Ser. No. 11/266,454, which was filed on 11 Nov. 2005 and has issued as U.S. Pat. No. 7,837,199. Each of these applications is incorporated herein by reference.
TECHNICAL FIELD
[0002] This disclosure relates to face seals and particularly to a carbon face seal whose performance deteriorates in a relatively benign way in comparison to conventional seals.
BACKGROUND
[0003] Carbon face seals are used in machinery, such as turbine engines, to effect a fluid seal between regions of high and low fluid pressure. For example, carbon seals are used to prevent hot, high pressure air from entering a bearing compartment operating at a lower pressure. A typical carbon seal for a turbine engine includes an annular carbon ring secured to an annular, nonrotatable, axially translatable seal housing. The seal also includes a seal seat affixed to a rotatable shaft and positioned axially adjacent to the carbon ring. The carbon ring comprises a base (or blank) and a nose projecting axially from the base. The nose is urged into contact with the seal seat by a combination of spring forces acting on the seal housing and the net resultant of axially opposing fluid pressure forces acting on the seal housing and the carbon ring. The contact area between the carbon ring and the seal seat equals the annular area of the nose. The contact between the nose and the seal seat resists fluid leakage across the seal in the radial direction, i.e. toward or away from the axis of rotation of the seal seat.
[0004] During operation, the nose gradually wears away. Ordinarily, the seal is replaced or refurbished before the nose is completely worn away. Occasionally, however, accelerated seal wear can result in complete wear of the nose so that the base of the carbon ring contacts the seal seat. As a result, the contact area between the carbon ring and the seal seat equals the annular area of the base, which is larger than the contact area of the nose. This affects the resultant of the axially opposing fluid pressure forces such that the net pressure force is less favorable for maintaining reliable, positive contact between the carbon ring and the seal seat. Unfortunately, the transition between the normal condition in which the nose contacts the seal seat, and the highly deteriorated condition in which the base contacts the seal seat, although it occurs very infrequently, can occur with little warning. In addition, more abrupt failure or deterioration of the carbon ring can have a similar adverse effect on the resultant of the fluid pressure forces. As a result there may be an unanticipated period of engine operation during which fluid leaks past the seal
[0005] What is needed is a carbon seal that deteriorates gracefully in order to exhibit a detectable and benign operating characteristic that clearly indicates that maintenance is required.
SUMMARY
[0006] A face seal assembly according to an exemplary aspect of the present disclosure includes, among other things, a seal seat and a seal element carried by a seal housing and cooperating with the seal seat to establish a seal. The seal housing includes a seal element support and a shroud. The shroud includes a tip having a head portion that tapers toward a neck portion that is reduced in size relative to the head portion. The tip is secured to a stem of the shroud through a set of circumferentially distributed countersunk holes.
[0007] In another exemplary embodiment of the above-described face seal assembly, the shroud is axially elongated relative to the support.
[0008] In another exemplary embodiment of any of the above-described face seal assemblies, the seal element includes a blank with a nose extending axially therefrom. The blank is stepped so that a first radial region extends axially beyond a second radial region of the blank.
[0009] In another exemplary embodiment of any of the above-described face seal assemblies, the first and second radial regions define respective first and second steps, and the tip is axially between the first and second steps.
[0010] In another exemplary embodiment of any of the above-described face seal assemblies, the seal seat is a seal ring, and the seal element is a carbon ring residing radially between the support and the shroud.
[0011] In another exemplary embodiment of any of the above-described face seal assemblies, the shroud is radially inboard of the support.
[0012] In another exemplary embodiment of any of the above-described face seal assemblies, the seal housing exclusive of the tip is made of a parent material and the tip comprises a second material different than the parent material.
[0013] In another exemplary embodiment of any of the above-described face seal assemblies, the second material is selected from the group of materials consisting of: a) materials more lubricious than the parent material; b) materials harder than the parent material; and c) materials more abradable than the parent material.
[0014] In another exemplary embodiment of any of the above-described face seal assemblies, the tip is a molded tip.
[0015] In another exemplary embodiment of any of the above-described face seal assemblies, the tip completely fills a corresponding one of the circumferentially distributed holes when the tip is secured to the stem of the shroud.
[0016] In another exemplary embodiment of any of the above-described face seal assemblies, the neck portion is positioned radially between the head portion and the seal element.
[0017] In another exemplary embodiment of any of the above-described face seal assemblies, the tip is configured to contact the seal seat.
[0018] In another exemplary embodiment of any of the above-described face seal assemblies, the seal housing is configured such that all portions of the tip reside radially inside the seal element.
[0019] A seal housing for a face seal according to yet another exemplary aspect of the present disclosure includes, among other things, a base with a seal element support and a shroud both extending from the base in a common direction. The seal element support and the base define a space for receiving a seal element. The shroud includes a tip having a head portion that tapers toward a neck portion that is reduced in size relative to the head portion. The tip is secured to a stem of the shroud through a set of circumferentially distributed countersunk holes.
[0020] In another exemplary embodiment of the above-described seal housing, the seal element includes a blank with a nose extending axially therefrom. The blank is stepped so that a first radial region extends axially beyond a second radial region of the blank. The first and second radial regions define respective first and second steps, and the tip is axially between the first and second steps.
[0021] In another exemplary embodiment of any of the above-described seal housings, the tip comprises a molded tip.
[0022] In another exemplary embodiment of any of the above-described seal housings, the tip completely fills a corresponding one of the circumferentially distributed holes when the tip is secured to the stem of the shroud.
[0023] In another exemplary embodiment of any of the above-described seal housings, the neck portion is positioned radially between the head portion and the seal element.
[0024] In another exemplary embodiment of any of the above-described seal housings, the tip is configured to contact the seal seat.
[0025] In another exemplary embodiment of any of the above-described seal housings, the seal housing is configured such that all portions of the tip reside radially inside the seal element.
[0026] The foregoing and other features of the various embodiments of the disclosed seal will become more apparent from the following detailed description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a cross sectional side elevation view showing an improved carbon seal.
[0028] FIGS. 2 , 3 and 4 are schematic views similar to FIG. 1 , but circumferentially offset from FIG. 1 , showing fluid pressure forces acting on a traditional seal in a normal or normally deteriorated condition, a highly deteriorated condition and a damaged or severely degraded condition respectively.
[0029] FIGS. 5-8 are schematic views similar to FIGS. 2 through 4 showing fluid pressure forces acting on an improved seal in normal, highly deteriorated, severely deteriorated and damaged conditions respectively.
[0030] FIG. 9 is a view illustrating a seal housing with a shroud whose tip is made of the same material as the rest of the seal housing.
[0031] FIG. 10 is a view similar to FIG. 9 showing a seal housing made of a parent material and having a shroud with a bonded or impregnated tip made of a second material.
[0032] FIGS. 11-13 are views similar to FIG. 9 but with a shroud having a tip in the form of an insert or attachment.
DETAILED DESCRIPTION
[0033] Referring to FIG. 1 , a shaft 20 for a rotary machine, such as a turbine engine, is rotatable about an axis 22 . A seal seat in the form of an annular ring 24 is secured against a shoulder on the shaft by a nut 26 . The seal seat extends radially outwardly from the shaft and circumscribes the axis. The seal seat is one component of a face seal assembly.
[0034] The face seal assembly also includes an annular, nonrotatable seal support 28 and a pair of annular seal housings 32 . Each seal housing includes a base 34 and a grooved secondary seal holder 36 at one end of the base. The secondary seal holder holds a secondary seal 38 in contact with a cylindrical bore of the seal support. The other end of the seal housing includes an axially extending shroud 42 and an axially extending support lip 44 that serves as a seal element support. The shroud 42 is radially offset from the lip 44 to define an annular space 46 for receiving a seal element. The shroud is also axially elongated relative to the lip. An annular flange 48 with circumferentially distributed slots 50 projects radially outwardly from the lip 44 .
[0035] The face seal assembly also includes a seal element 52 residing in the space 46 and secured to the lip 44 by an interference fit. The seal element includes a base or blank 54 and a nose 56 extending axially from the blank. The blank is double stepped such that a first, radially inboard region 58 of the blank extends axially beyond a second radially outboard region 60 of the blank to define a first or radially inner step 61 and a second or radially outer step 63 . Moreover, inner step 61 resides axially beyond the tip of shroud 42 whereas outer step 63 does not reside axially beyond the shroud tip. In other words, the tip of the shroud is axially between the steps 61 , 63 . The seal element is typically made of a graphitic carbon material and is often referred to as a carbon element even though it is not made of pure carbon. In the illustrated application, the carbon element is annular and therefore can be referred to as a carbon ring.
[0036] A set of circumferentially distributed support pins such as representative pin 64 , each projects axially from the seal support 28 and passes through a corresponding slot 50 in the flange 48 . Springs 66 (depicted in FIGS. 5-8 ) are circumferentially offset from the pins 64 . The springs are compressed between the flange 48 of housing 32 and the support 28 so that they exert a force on the flange 48 to urge the nose of the carbon ring into contact with the seal seat 24 . The interface between the nose and the seal seat may be unlubricated or “dry” as seen at the left side of the illustration, or it may be lubricated or “wet” as seen at the right side of the illustration. In a wet seal, lubricant flows to the interface by way of circumferentially distributed lubricant passages 68 in the seal seat.
[0037] During engine operation, high pressure air is present in the annular cavity 70 radially inboard of the seal and radially outboard of the shaft 20 . Lower pressure air intermixed with oil occupies a bearing compartment 72 , which is the region outboard of the seal. The seal resists leakage of the higher pressure air into the lower pressure bearing compartment.
[0038] Referring additionally to FIG. 2 , the operation of the above-described shrouded seal is best understood by first considering a conventional seal. FIG. 2 shows the conventional seal in a normal or substantially undeteriorated condition. FIG. 2 also suffices to show the seal in a normally deteriorated condition, i.e. with the nose only partially worn away. The arrow F.sub.s represents the force exerted on the seal housing 32 by the springs 66 . Force graphs f.sub.o and f.sub.c show the axially opposing, radially distributed forces F.sub.O, F.sub.C acting on the seal housing, carbon ring and secondary seal as result of the disparate pressures in cavity 70 and compartment 72 . The force vectors in graphs f.sub.o and f.sub.c are illustrated as terminating on respective common planes to facilitate comparisons of the aggregate pneumatic forces. However those skilled in the art will recognize that the forces actually act on the axially facing surfaces of the seal housing, carbon ring and secondary seal. Graph f.sub.c shows a relatively high pressure acting on the high pressure side of the seal and a low pressure acting on the low pressure side of the seal. Graph f.sub.o shows high pressure acting on the high pressure side of the seal, low pressure acting on the low pressure side of the seal, and a radially varying pressure in a transition region across the nose 56 of the carbon ring. As is evident, the nose throttles the high pressure down to the low pressure across a narrow radial region. The combination of F.sub.S and F.sub.C exceeds F.sub.O to keep the seal closed.
[0039] FIG. 3 shows the conventional seal in a highly deteriorated condition in which the nose has been entirely worn away. F.sub.C is the same as in FIG. 2 . However because the nose has been worn away, the base portion 54 of the carbon ring throttles the high pressure down to the low pressure across a radial transition region that is relatively wide in comparison to the transition region of FIG. 2 . As a result higher pressure, and therefore higher forces, act over a larger radial region than is the case in FIG. 2 . Accordingly, the aggregate force F.sub.O acting on the highly deteriorated seal of FIG. 3 exceeds the aggregate force F.sub.O acting on the normal or normally deteriorated seal of FIG. 2 . Furthermore, F.sub.S is slightly smaller than it is in FIG. 2 due to the increased spring elongation (decompression) and consequent reduction in spring force. Due to the change in forces acting on the seal, there is a potential for F.sub.O to exceed the combination of F.sub.S and F.sub.C resulting in separation of the carbon ring 52 from the seal seat 24 . This separation will allow leakage through the resulting gap as indicated by the small fluid flow arrows. The force graphs and forces would be as shown in FIG. 4 if the carbon ring were broken away along part or all of its circumference. This would also result in the potential for leakage as indicated in FIG. 4 .
[0040] As mentioned previously, the transition between the normal condition in which the nose contacts the seal seat, and the highly deteriorated condition or severely deteriorated conditions occurs very infrequently, but can occur with little warning. As a result there may be an unanticipated period of engine operation during which fluid leaks past the seal.
[0041] FIG. 5 corresponds to FIG. 2 , but shows the improved, double stepped shrouded seal in an undeteriorated or normally deteriorated condition. As is evident, the forces are substantially the same as those of FIG. 2 , with the result that the seal is urged closed.
[0042] FIG. 6 shows the improved, double stepped shrouded seal in a highly deteriorated condition similar to the condition of the conventional seal in FIG. 3 . The blank of the carbon ring of FIG. 6 includes the first radial region 58 and its associated step 61 extending axially beyond the second radial region 60 and its associated step 63 . In addition, the seal of FIG. 5 includes the shroud 42 on the seal housing. The axially extended first region 58 throttles the high pressure across a radial transition region that is radially narrower than the transition region of FIG. 3 . Accordingly, the aggregate force F.sub.O of FIG. 6 is less than the aggregate force F.sub.O of FIG. 3 . As a result, the carbon ring 52 of FIG. 6 is less likely to separate from the seal seat 24 than is the carbon ring of FIG. 3 .
[0043] FIG. 7 shows the improved, shrouded seal in a more severely deteriorated condition. In comparison to FIG. 6 , FIG. 7 shows the carbon ring 52 worn back essentially to the shroud 42 and therefore shows a throttling effect attributable to the shroud. The shroud and the axially extended first region 58 of the carbon ring throttle the high pressure across a radial transition region that is radially narrower than the transition region of FIG. 3 . Accordingly, the force magnitude F.sub.O of FIG. 7 is less than the force magnitude F.sub.O of FIG. 3 . As a result, the carbon ring of FIG. 7 is less likely than the carbon ring of FIG. 3 to separate from the seal seat 24 and permit leakage. As further wear of the carbon ring occurs, the shroud tip will eventually contact the seal seat 24 resulting in a more pronounced throttling effect.
[0044] FIG. 8 shows the improved, shrouded seal in a damaged condition in which the carbon ring has been broken away over all or part of its circumference. The shroud 42 contacts the seal element and throttles the high pressure across a radially narrow transition so that the seal remains closed and resists leakage.
[0045] As is evident, the improved, shrouded seal deteriorates more gradually than a conventional unshrouded seal. The gradual deterioration is desirable because it manifests itself as noticeable but minor anomalies in engine performance. These minor anomalies make the engine operator aware that seal replacement or repair is required. Such replacement or repair may then be effected before the seal deteriorates enough to cause more significant problems.
[0046] With the construction and operation of the seal having now been described, certain variants may now be better appreciated.
[0047] FIG. 9 shows a seal like that of FIGS. 1 and 5 - 8 in which the housing 32 is made of a selected material. The shroud has a tip 74 at its axial extremity remote from the housing base 34 . The tip is made of the same material as the rest of the housing.
[0048] FIG. 10 shows a seal in which the housing 32 is made of a parent material and the shroud has a tip 74 which is a region of the shroud impregnated with a second material. Alternatively, the shroud tip may be a feature made of or impregnated with a second material and bonded to the rest of the shroud or may be a coating. The second material may be any material having characteristics that are desirable when the tip contacts the seal seat 24 . These include materials more lubricious than the parent material, materials harder than the parent material and materials more abradable than the parent material.
[0049] FIGS. 11-13 show a seal in which the shroud comprises a stem 76 and a tip in the form of an insert or attachment 78 affixed to the stem. In FIG. 11 the insert is affixed with a radially outer snap 82 . In FIG. 12 the insert is affixed with a radially inner snap 84 . In FIG. 13 the insert is a molded tip secured to the stem 76 through a set of circumferentially distributed countersunk holes 86 . The tip insert may be made of a material having characteristics that are desirable when the tip contacts the seal ring 24 . These include materials more lubricious than the parent material, materials harder than the parent material and materials more abradable than the parent material.
[0050] Although the improved seal has been shown and described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the invention as set forth in the accompanying claims. | One embodiment of the seal housing for a face seal described herein include a base with a seal element support and a shroud both extending from the base in a common direction. The seal element support and the base define a space for receiving a seal element. The shroud includes a tip having a head portion that tapers toward a neck portion that is reduced in size relative to the head portion. The tip is secured to a stem of the shroud through a set of circumferentially distributed countersunk holes. | 5 |
BACKGROUND OF THE INVENTION
The process of this invention relates to a process for the production of metallic magnesium by electrolytically decomposing a molten salt bath containing magnesium chloride with the periodic addition of inorganic salts of molybdenum, or tungsten, metallic molybdenum or tungsten, or mixtures thereof.
It is known from Cervenka, et al., U.S. Pat. No. 3,565,917 that vanadium compounds when added to electrolytic magnesium cells result in increased current or cell efficiencies. However, the use of these additives has the disadvantage that vanadium rapidly volatilizes out of the exhaust vents and/or dissipates into the sludge which is accumulated in these cells and must be removed periodically.
SUMMARY OF THE INVENTION
It now has been discovered that magnesium can be produced by an improved process wherein magnesium chloride is electrolytically decomposed in a molten salt bath comprising an alkali metal chloride or mixtures thereof. The essential steps in the process are as follows:
A. heating and fusing the salt bath at a temperature in the range from about 660° to about 900° C.,
B. passing direct current through said bath to decompose the magnesium chloride,
C. maintaining a concentration of magnesium chloride in the salt bath in the range from about 5 to about 35 percent by weight by periodic additions thereof,
D. adding periodically to the salt bath sufficient amounts of an additive selected from the group consisting of inorganic salts of molybdenum, inorganic salts of tungsten, metallic molybdenum, metallic tungsten, or mixtures thereof which will coat the cathode surface with said metal and thereby increase the agglomeration of molten magnesium, and
E. recovering molten magnesium from said salt bath.
Generally, about 100 to about 1000 parts per million of the additive is added periodically to the salt bath.
The advantage of this invention is that the cell efficiency is increased since the molybdenum and/or tungsten additive appears to result in a coating of the cathode with a thin coat of the corresponding metal. This coating which is generally less than 15 angstroms promotes the wetting of the cathode with magnesium. This in turn results in the liberation of relatively large globules of magnesium which separate from the bath for recovery. This is in contrast to the prior art methods wherein relatively larger amounts of magnesium were lost in the sludge since the relatively finer droplets of magnesium produced at the cathode did not properly coalesce and separate from the molten bath as a separate phase of molten magnesium.
DETAILED DESCRIPTION
The process of this invention was carried out in an experimental cell wherein a steel cylindrical container having a cover plate was wrapped with electrical heating wires. The cover plate had openings therein for a graphite rod which was suspended in the center therefrom into the salt bath to act as the anode. A steel cathode in the form of a ring was mounted directly to and near the bottom of the container with the anode located in the center thereof. Vicor or high silica glass tubes were provided to supply an argon gas blanket over the molten salt bath and to remove chlorine gas from the area between the steel cathode ring and central anode.
The temperature of the bath was measured with a chromel-alumel thermocouple. The direct current power was applied by means of a Powermate DC power supply to the electrodes. The heat to the heating wires was controlled manually by means of autotransformers. The magnesium chloride concentration in the bath was maintained by means of an automatic feeder which introduced predetermined amounts of feed into the cell at regular intervals.
The process of this invention is equally useful in magnesium cells in which the molten magnesium floats to the surface as well as in lithium cells as illustrated by U.S. Pat. No. 2,950,236 wherein the magnesium sinks to bottom of the bath.
In general the temperature range of the salt bath used herein ranges from about 660° to about 900° C with the preferred range being from about 670° to about 750° C.
The magnesium chloride is added to the molten bath so as to maintain a concentration in the range from about 5 to about 35 weight percent with a preferred range being from about 10 to about 20 weight percent.
The inorganic salts of molybdenum and tungsten which are useful in this invention are generally those which have a low volatility at the above temperature ranges and which have a high percentage of metal contained therein. Less preferred but still useful are more volatile compounds.
The above metals in metallic form can be used if in a finely divided form i.e. generally less than 20 mesh size.
Examples of useful salts of molybdenum are molybdenum oxides such as the di, tri and sesqui oxides; the molybdenum halides such as MoCl 3 ; the ammonium, alkali metal, and alkaline earth metal molybdates such as Na 2 MoO 4 , (NH 4 ) 2 MoO 4 , K 2 Mo 4 O 13 , CaMoO 4 and the like or mixtures of the same.
Examples of useful salts of tungsten are tungsten oxides such as the di, tri and pentoxides; the tungsten oxyhalides such as WO 2 Br 2 , WOCl 4 , and WOF 4 ; the tungsten halides such as WCl 6 , WCl 2 , WF 6 ; the ammonium, alkali metal and alkaline earth metal tungstates such as (NH 4 ) 2 WO 4 , Na 2 WO 4 , Li 2 WO 4 , BaWO 4 , and the like or mixtures of the same.
Salts of molybdenum and tungsten with heavy metals such as nickel, copper, iron, zinc and non-metals such as silicon, boron, and arsenic are to be avoided since they either increase the sludge problem or create undesirable alloys with the magnesium.
It has been found that the above metals or the inorganic salts thereof will give a coating of tungsten or molybdenum on the cathode generally less than about 15 angstroms and in the range from about 1.5 to about 10 angstroms.
It has been further found that the above metal coating causes a wetting of cathode surface by the magnesium with the contact angle being less than 10°. This is most unusual since the other element in Group VIB of the periodic table, chromium, does not have this effect and in fact its effect is adverse to the production of magnesium as is seen by control II hereinafter.
Bath Compositions and Materials
The compositions of the salt baths used herein are
______________________________________ Bath I Bath IINaCl 56% 53%KCl 15% 18%CaCl.sub.2 12% 12%CaF.sub.2 1% 1%MgCl.sub.2 15% 15%MgO 1% 1%______________________________________
Reagent grade sodium, potassium, and calcium chlorides and calcium fluoride were used for the bath. The magnesium chloride used was about 96% pure, the chief contaminants being sodium, potassium, and calcium chlorides and magnesium oxide, hydroxychloride, and oxychloride.
Control I
5200 Grams of bath I were melted and the temperature was brought up to 700° C. Eight amperes of direct current were applied to the cell. Cell feed containing approximately 96% magnesium chloride was fed at a rate of about 320 gms per day. The bath was dipped daily to remove the produced magnesium. The metal was washed with cold water and dried before weighing. The bath was analyzed twice a week for all major constituents except calcium fluoride which was analyzed weekly. When the analysis indicated the bath composition had changed, additions were made and the rate of feed addition altered to maintain a relatively constant composition.
The cell was run for 13 days. On the 14th day the cell efficiency was averaged and reported as in Table I as day #1. This was repeated for 39 more days to eliminate the day to day variations. The overall average for the 14 days averages was 75.34%.
TABLE I__________________________________________________________________________(no additive) Cell Eff. Cell Eff. Mg Cell 14 Day Mg Cell 14 Day Prod. Efficiency Average Sludge Prod. Efficiency Average SludgeDay (gms) (%) (%) (gms) Day (gms) (%) (%) (gms)__________________________________________________________________________1 56.0 64.4 60.3 N.A. 11 62.4 84.9 71.7 N.A.2 63.0 72.4 64.9 149 12 61.9 71.1 71.5 N.A.3 65.4 75.1 67.5 N.A. 13 45.1 51.8 69.7 N.A.4 61.0 70.1 68.1 225 14 58.1 66.8 69.9 1825 65.1 74.8 70.8 N.A. 15 55.6 63.9 69.2 2006 65.3 75.0 68.3 N.A. 16 64.5 74.1 70.0 507 59.6 68.5 68.2 N.A. 17 63.8 73.3 70.2 758 67.4 77.4 69.0 155 18 66.4 76.3 70.3 269 68.0 78.2 69.8 N.A. 19 78.0 89.7 71.3 6210 73.9 84.9 71.2 N.A. 20 68.9 79.1 72.1 6221 68.9 79.1 72.1 62 31 73.0 83.9 80.6 2522 73.4 84.4 71.9 60 32 74.5 85.6 80.3 3523 73.0 83.9 71.9 N.A. 33 73.0 83.9 80.6 4524 73.3 84.2 72.8 N.A. 34 74.0 85.0 81.8 N.A.25 74.9 86.1 73.8 25 35 69.8 80.2 81.5 8226 76.3 87.7 76.4 N.A. 36 65.7 75.5 80.9 N.A.27 75.4 86.7 77.8 N.A. 37 72.9 83.8 80.9 N.A.28 70.1 80.5 79.0 N.A. 38 68.8 79.1 80.4 N.A.29 66.3 76.2 79.1 N.A. 39 121.0 69.5 77.8 6030 74.4 85.5 80.0 20__________________________________________________________________________
EXAMPLE I
5200 gms of bath I were melted and the temperature was brought to 700° C. Eight amperes of direct current were applied to the cell. Cell feed containing about 96% magnesium chloride was fed at a rate of about 320 gms per day. The bath was analyzed as in Control I. The metal was dipped daily.
In this experiment, 2 gms of molybdenum trioxide were added to the bath at start-up. Another 1 gm was added every 7 days. The dates of all additions are marked with an asterisk in Table II.
The data in Table II indicates the overall average for the 14 day averages was 79.73%. A significant increase over Control I.
TABLE II__________________________________________________________________________ Cell Eff. Cell Eff. Mg. Cell 14 Day Mg. Cell 14 Day Prod. Efficency Average Sludge Prod. Efficiency Average SludgeDay (gms) (%) (%) (gms) Day (gms) (%) (%) (gms)__________________________________________________________________________ 1* 71.0 81.6 71.1 66 11 66.6 76.5 81.0 602 68.7 79.0 74.2 47 12 60.1 69.1 80.9 313 68.4 78.6 75.3 63 13 76.7 88.4 81.5 614 74.0 85.0 77.0 60 14 62.3 71.6 80.8 315 61.3 70.5 77.0 10 15* 66.4 76.3 80.6 706 88.8 102.1 79.8 90 16 75.5 86.8 81.2 647 75.1 86.3 79.8 35 17 73.4 84.4 81.1 64 8* 69.1 79.4 79.6 26 18 65.5 75.3 81.5 549 71.4 82.1 80.2 63 19 76.2 87.6 80.5 7510 70.5 81.0 80.5 42 20 68.5 78.7 80.0 2521 79.4 91.3 80.8 49 31 81.4 93.5 79.5 022* 68.7 79.0 80.6 20 32 69.5 74.1 78.5 023 75.2 86.4 81.0 35 33 66.1 76.0 78.3 024 64.6 74.2 80.8 34 34* 79.3 91.1 78.3 7025 76.8 88.2 82.2 20 35 74.3 85.4 78.8 026* 68.8 79.1 81.5 0 36 61.3 70.4 77.6 027* 67.9 78.0 82.0 0 37 60.3 69.3 77.3 028 44.0 50.6 80.2 0 38 74.9 86.1 77.1 029 65.9 74.1 78.5 0 39 74.3 85.4 77.6 030 59.0 67.8 78.1 0 40 80.7 92.7 78.6 041* 95.8 110.1 82.9 80 44 66.1 76.0 81.6 042 59.2 68.0 82.9 0 45 76.3 87.7 82.5 043 58.0 66.7 82.8 0 46 72.3 83.1 83.0 0__________________________________________________________________________ *Day of addition of MoO.sub.3
EXAMPLE II
5200 gms of bath II were melted and the temperature was brought up to 700° C. Eight amperes of direct current were applied. Cell feed containing about 96% magnesium chloride was fed at a rate of about 320 gms per day. The bath was analyzed on the same schedule as the previous examples. The metal was dipped every other day.
1 gm of sodium tungstate was added after the cell had been operating for about 14 days. On each of the next six days, 1 gm of tungstate was added. Thence, 1 gm was added weekly. This is shown by Table III. The overall average for the cell efficiency was 78.88%.
TABLE III______________________________________(Na.sub.2 WO.sub.4 additive) Cell Eff. Mg Cell 14 Day Prod. Efficiency AverageDay (gms) (%) (%)______________________________________ 1* 137.5 79.0 63.8 2* -- -- -- 3* 143.7 82.6 70.8 4* -- -- -- 5* 112.0 64.4 73.0 6* -- -- -- 7 126.2 72.5 73.3 9 144.0 82.7 76.411 125.0 71.8 75.813* 166.6 95.7 78.415 146.2 84.0 79.117 154.4 88.7 80.019* 160.0 92.0 83.921 129.0 74.1 84.123 135.5 77.9 83.425 159.0 91.3 86.327 130.5 75.0 83.329 127.0 73.0 81.731 135.0 77.6 80.133* 123.0 70.7 77.135 139.0 79.9 77.937 157.5 90.5 79.739 167.5 96.3 80.441* 151.5 87.1 82.143 158.5 91.1 84.7______________________________________ *day of addition of Na.sub.2 WO.sub.4
Control II
5200 gms of bath II were melted and the temperature was brought up to 700° C. Eight ampheres of direct current were applied. Cell feed containing about 96% magnesium chloride was fed at a rate of 320 to 355 gms a day (the higher figure at the higher production rates). The bath was analyzed as per the schedules in the other examples. The metal was dipped every other day.
1 gm of K 2 Cr 2 O 7 (potassium dichromate) was added after the cell had been operating for about 14 days. A similar amount was added at each of the intervals indicated by the asterisk in Table IV. The overall average for the cell efficiency was 72.06% which is below control I with no additives.
TABLE IV______________________________________(K.sub.2 Cr.sub.2 O.sub.7 additive) Cell Eff. Mg Cell 14 Day Prod. Eff. AverageDay (gms) (%) (%)______________________________________1* 135.6 77.9 70.7 3 127.8 73.4 69.6 5 126.3 72.6 69.6 7 117.5 67.5 70.19* 148.5 85.3 71.311 140.0 80.5 76.013 114.0 65.5 74.215* 118.0 67.8 73.417 115.0 66.1 62.219 142.5 81.9 73.5______________________________________ *day of addition of K.sub.2 Cr.sub.2 O.sub.7
EXAMPLE III
The procedure of Control II was repeated except that 1 gram of molybdenum oxide (MoO 3 ) was added to bath daily for 6 days and then at intervals as shown in Table V. The overall average for the cell efficiency was 80.19% which is vastly superior to the controls.
TABLE V______________________________________(MoO.sub.3 additive) Cell Eff. Mg Cell 14 Day Prod. Eff. AverageDay (gms) (%) (%)______________________________________1* 136.0 78.2 75.02* -- -- --3* 135.0 77.6 73.94* -- -- --5* 142.0 81.6 74.16* -- -- -- 7 133.0 76.4 75.7 9 145.0 83.3 77.911 149.3 85.8 80.713 154.3 88.7 81.7 15* 153.5 88.2 83.117 139.0 79.9 83.419 153.0 87.9 84.321 150.0 86.2 85.7 23* 158.0 90.8 86.8______________________________________ *day of addition of MoO.sub.3 | A process for the production of metallic magnesium wherein a molten salt bath containing sodium chloride, magnesium chloride, potassium chloride, calcium chloride and magnesium fluoride is electrolytically decomposed with a cathode and an anode and wherein there is added periodically inorganic salts of molybdenum or tungsten, metallic molybdenum or tungsten, or mixtures thereof in sufficient amounts to coat the cathode surface with molybdenum or tungsten and thereby increase the recovery of magnesium.
The advantage of the process is that less sludge is formed and of the sludge that is formed there is less magnesium entrapped therein. A further advantage is that the magnesium is produced with a higher cell efficiency. | 2 |
BACKGROUND OF THE INVENTION
(1) Field of the Invention
This invention relates to a lock for security screen doors and is suitable for other doors or windows which are hingedly mounted.
(2) Description of the Prior Art
Over the years many different types of locks have been proposed and adopted. One common type is the so-called "mortise" lock which is suitable for hinged doors or windows.
To provide added security, deadlocking arrangements have been incorporated into these locks in an attempt to prevent the locks being picked or forced. While these deadlocking arrangements have been successful in certain areas, a problem has been found that these deadlocking arrangements can be circumvented by shaking the door or window to cause the lock tongue to be freed.
BRIEF SUMMARY OF THE INVENTION
It is an object of the present invention to provide a lock which cannot be released by shaking the door or window in which it is mounted.
It is a preferred object to provide a deadlock where the locking block which engages the normally extending lock tongue has a stop means operable to restrain the locking block in an engagement position.
It is a further preferred object to provide a mortise-type lock which has a reversible lock tongue, which can be removed from the lock body without the need to open the latter.
Other preferred objects will become apparent from the following description.
In the broad aspect, the present invention resides in a lock including:
a body;
a lock tongue normally extending from the body;
a locking block slidably movable in the body between a first position free of the lock tongue and a second position preventing retraction of the lock tongue;
an abutment in the body; and
a stop lever movably mounted on the locking block and adapted to engage the abutment when the locking body is in the second position to restrain the locking body in the second position.
Preferably the stop lever is pivotally mounted on the locking block, and a spring means urges the stop lever into engagement with the abutment.
Preferably the lock is provided with a lock cylinder having a laterally extending cam adapted to move the locking block between the first position and the second position and to urge the stop lever out of engagement with the abutment against the spring means. Preferably an abutment face on the abutment is engaged by a complementary face on the stop lever.
Preferably there is a lateral bore through the locking block, and a pair of spaced apertures in the body adjacent the locking block, wherein the spring means includes:
a ball mounted in the lateral bore adapted to be seated in a respective one on the spaced apertures when the locking block is in the first position or in the second position.
Preferably the lock includes a slot in one side of the lock tongue adapted to be engaged by the locking block in the second position; a pin extending laterally from the lock tongue; a shaft rotatably mounted in the body; a handle operatively connected to the shaft and a lever mounted on the shaft in engagement with the pin and adapted to retract the lock tongue into the body on rotational movement of the handle. Preferably the lock tongue has an opposed pair of said pins, the lock tongue being reversible in the body.
Preferably a stop member mounted in the body and movable between a first position to retain the lever in engagement with the pin and a second position to free the lever from the pin to enable the lock tongue to be removed from the body.
BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWING
To enable the invention to be fully understood, a preferred embodiment will now be described with respect to the accompanying drawings, in which:
FIG. 1 is a sectional side view of the lock in the locking position with both the locking block and stop lever engaged;
FIG. 2 shows the lock of FIG. 1 with the locking block engaged and the stop lever released.
FIG. 3 shows a portion of the lock of FIG. 1 with both the locking block and stop lever released.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The lock has a body 10 adapted to be fitted in a suitably dimensioned aperture 11 in a security screen door frame 12. The body 10 has a front plate 13 provided with a pair of extension pieces 14 having holes therethrough (not shown) to receive screws 15 to secure the body to flanges 16 on the frame 12. The body 10 has a back plate 17, a top plate 18, bottom plate 19, a fixed side 20 and a removable cover side (not shown).
A striker plate 21 is secured to the door architrave (not shown) by a pair of screws 22 passing through suitable holes 23. The striker plate 21 has a central aperture 24, and a side flange 25 to locate the striker plate laterally on the architrave.
A mortise-type lock tongue 26 is slidably mounted in the body 10 and normally extends through an aperture 27 on the front plate 13 which is aligned with the aperture 24 in the striker plate 21. The rearward portion 28 of the tongue 26 is of reduced thickness and has a pair of opposed pins 29 extending laterally therefrom.
A shaft 30 is rotatably mounted in the body 10 on the fixed side plate 20 and the removable cover plate and has a handle 31 secured to each end thereof. A lever 32 is mounted on the shaft 30 and has a hook 33 engaging one of the pins 29 on the lock tongue 26. As the handles 31 are depressed, the shaft 30 is rotated in a clockwise direction to cause the lever 32 to retract the lock tongue 26 into the body 10 against the torsion spring 34 (with its head open to the exterior of the body 10).
A screw 35 is threadably mounted in block 36 in the fixed side plate 20 and extends into the body and engages the side face of the lever 32 to retain the hook 33 in engagement with the pin 29. To enable the lock tongue 26 to be withdrawn from the body 10 via the aperture 27, the screw 35 may be rotated to withdraw the free end of the screw 35 into the block 36. The hook 33 falls free of the pin 29 and the lock tongue 26 may be withdrawn. To convert the lock from e.g. right-hand hung to left-hand hung, the lock tongue 26 is inverted and replaced in the body 10. The handle 31 is depressed to cause the hooks 33 to engage the second of the pins 29 and the screw 35 is caused to extend from the block 36 to retain the hook 33 in position.
A locking block 37 is slidably mounted on the body 10 rearwardly of the front plate and is guided by block 36 or guide flange 38. The locking block 37 is movable between a first position free of the lock tongue 26 (e.g. as in FIG. 3) and a second position (e.g. as in FIGS. 1 and 2) where the locking block 37 is engaged in one of a pair of opposed slots 39 in the sides of the lock tongue 26 when the latter is in the extended position. The lower portion 40 of the locking block 37 is of reduced width. A stop lever 41 has a ball 42 pivotally mounted in a socket integral in the lower portion 40. The stop lever 41 is pivotally movable between an extended position shown in FIG. 1 and a retracted position (lying closely adjacent to the lower portion 40) shown in FIGS. 2 and 3.
An abutment 44 is formed on the bottom plate 19 and fixed side plate 20 and extends into the body 10. An abutment face 45 is formed at an angle to the axis of movement of the locking block 37 and is engageable by a complementary surface 46 on the stop lever 41 when the latter is in the extended position (see FIG. 1).
A bore 47 is formed laterally through the lower portion 40 and a ball 48 is mounted in the bore 47 and is adapted to be seated in a lower hole 49 in the front plate 13 when the locking block 37 is in the first position (see FIG. 3) and in an upper hole 50 when the locking block 37 is in the second position (see FIGS. 1 and 2). A compression spring 51 is fitted in the bore 47 and is interposed between the ball 48 and the stop lever 41 to urge the ball 48 into sealing engagement in either hole 49 or 50 and to urge the stop lever 41 to the extended position.
A lock cylinder 52 is mounted in the body 10 (and extends through the fixed side plate 20 and removable cover plate) and has a cam 53 which is movable between the three positions shown in the FIGS.
The operation of the lock will now be described.
As shown in FIG. 1, the locking block 37 is in its second position and is engaged in one of the slots 39 to retain the lock tongue 26 in the extended position in engagement with the aperture 24 in the striker plate 21. The ball 48 is seated in the upper hole 50 and the stop lever 41 is in the extended position with its complementary face 46 engaged with the abutment face 45 to prevent the locking block 37 being shaken free of the slot 39. Cam 53 is in its upper position.
Referring to FIG. 2, the lock cylinder 52 is operated to move the cam 53 to its intermediate position. The cam 53 engages the stop lever 41 and urges it to its retracted position adjacent the lower portion 40 and free of the abutment 45. The locking block 37 is not moved and the ball 48 remains seated in upper hole 50.
To release the locking block 37 from the slot 39 (and thereby allow lock tongue 26 to be moved to its retracted position by handles 31), the lock cylinder 52 is further operated to move the cam 53 to its lower position (see FIG. 3). The locking block 37 is pulled downwardly until the ball 48 is seated in the lower hole 49. The lock can now be operated in the same manner as an ordinary mortise-type lock by the handles 31.
To deadlock the lock tongue 26, the operation is reversed.
As the abutment face 45 is angled to the axis of movement of the locking block 37, it resists any likelihood of the stop lever 41 accidentally being released from the abutment 44 should the door frame 12 be shaken. In addition, the abutment face 45 resists any downward movement of the locking block 37 at the same time.
In a modified form of the lock, the stop lever 41 may be slidably mounted on the locking block 37 to extend laterally therefrom and have an upwardly inclined cam face engageable by the cam 53 to free the stop lever 41 from the abutment 44 before the locking block 37 is released from the slot 39. While the lock has been described as a mortise-type lock, the described and illustrated embodiment may be used on other types of locks which have sliding tongues or bolts which extend from, and are retracted into, the lock body.
Various other changes and modifications may be made to the embodiments described without departing from the scope of the present invention. | A mortise-type deadlock for hingedly-mounted doors and windows where a locking block engages the lock tongue in the extended position. A pivotally-mounted stop lever on the locking block engages an abutment in the lock body to prevent the locking block being shaken free of the lock tongue. The lock tongue may be reversible and may be removed from the lock body by operating a stop member operable from the exterior of the lock body. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to a joint for a truss structure, more particularly such a joint for removably attaching a ball member to an end of a bar member to form a truss structure.
It is known to submerge truss structures under water to form an artificial habitat for fish, or for minimizing the erosion effect of waves on the undersea terrain. Truss structures are typically made by joining a plurality of bar members together by means of concrete balls. The bar member may comprise a concrete cylinder through which a tension member, such as a tension cable, extends. The ends of the tension cable may be attached to the concrete balls at opposite ends of the bar member so that tensile forces exerted on the bar member are borne by the tension cable, while compression forces exerted thereon are borne by the concrete cylinder.
The conventional truss structure elements are difficult to assemble, since the ends of the tension member extending through the bar must be attached to the ball member. This is usually accomplished by a press fitting connection between projection members fixed on the end of the tension member which must be inserted into holes on the ball member.
Another disadvantage of the known truss joints is their poor assembly accuracy caused by the inability of the connecting mechanisms to facilitate adjusting the length of the tension member.
Additional disadvantages involve the fabrication of the concrete ball member. Since the concrete ball used in conventional truss structures is made in a hollow spherical shape to compensate for the difference in specific weights between concrete and sea water, it must be formed around a spherical core. This spherical core is extremely difficult to remove from the concrete ball member.
As is well known in the art, concrete is strong against compression forces, but is weak against tensile forces. Therefore, a concrete ball member cannot bear large tensile forces. Thus, it is quite desirable to provide a ball member having simplified construction, while at the same time increasing its strength against tensile forces.
SUMMARY OF THE INVENTION
A joint structure for removably attaching a ball member to an end of a bar member to form a truss structure is disclosed having an engagement member attached to the ball member, which engagement member has an exterior portion extending outwardly of the outer surface of the ball member, and an attachment device associated with the end of the bar member which removably engages the exterior portion of the engagement member. The joint structure according to the present invention may be utilized with bar members with or without tension rods extending through the bar member. If the bar member is made of concrete, quite obviously a tension member will be necessary in order to properly react the tension forces exerted on the bar member.
In a first embodiment, the end of the tension member physically engages a hollow tubular engagement member extending from the ball member so that the end of the bar member can be easily attached to the ball member externally of the ball member. A tension adjusting device is provided on the tension rod to adjust the tension after the rod has been engaged with the engagement member.
In a second embodiment, a nut collar is attached to the end of the tension rod and may be threaded onto the exterior portion of the engagement member. In both the first and second embodiments, a resilient device is operatively interposed between the end of the bar member and the exterior surface of the ball member to facilitate adjustment during the assembly process.
In a third embodiment, the bar member is utilized without a tension rod and is directly attached to a stop member which is, in turn, attached to the exterior portion of the engagement member.
In all of the embodiments, the ball structure may comprise a spherical shell made of metal of fiber reinforced plastic which is located within a hollow concrete sphere. The spherical shell is not removed from the interior of the concrete sphere, but, instead, is used to increase the tensile force resistance of the ball member. The spherical shell may be imbedded in the ball member at the time of forming the concrete ball and can be used as a molding core. This allows the ball to be manufactured easily and efficiently, while at the same time increases the tensile strength of the finished structure.
According to this invention, the bar member is joined to the ball member simply and efficiently by attaching the bar member to an engagement member provided on the exterior of the ball member. Since the joint structure of this invention may adjust the length of the bar member through the joint, the accuracy of assembly is increased without requiring a special length adjusting mechanism.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a truss having the joint structure according to the present invention.
FIG. 2 is a partial, cross-sectional view of a first embodiment of the joint structure according to the present invention.
FIG. 3 is a cross-sectional view taken along line A--A in FIG. 2.
FIG. 4 is a cross-sectional view taken along line B--B in FIG. 2.
FIG. 5 is a cross-sectional view taken along line C--C in FIG. 2.
FIG. 6 is a partial, cross-sectional view of a second embodiment of the joint structure according to the present invention.
FIG. 7 is a cross-sectional view taken along line D--D in FIG. 6.
FIG. 8 is an enlarged view of area E in FIG. 6.
FIG. 9 is a partial, cross-sectional view of a third embodiment of the joint structure according to the present invention.
FIG. 10 is an exploded, cross-sectional view of the joint structure shown in FIG. 9.
FIG. 11 is a partial, cross-sectional view illustrating a modification of the joint structure illustrated in FIG. 9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a basic truss unit of the truss structure according to the present invention comprising six bar members 1 joined together by means of four ball members 2 to form a three dimensional structure. A plurality of these basic truss units may be combined together to form a truss structure of virtually any desired configuration.
A first embodiment of the joint structure according to this invention is illustrated in FIGS. 2-5. The ball member 2 is a hollow concrete sphere having a spherical shell 3 imbedded therein. The spherical shell 3 may be made of metal, fiber reinforced plastic, or other materials which will increase the tensile strength of the ball member 2. The spherical shell 3 can be used as a core on which the concrete layer is molded during the fabrication of the ball member. Since the spherical shell 3 forms an integral part of the ball member 2, it need not be removed therefrom after the concrete sphere has cured.
The spherical shell 3 is provided with a plurality of engagement members which, in this particular embodiment, comprise a collar 4 having a hollow interior. The collar 4 has a portion extending exteriorly of the outer surface of the ball member 2. The outer surface of the ball member 2 may define a plurality of recesses 5 located around the exterior portions of collars 4. The outer surface may also define recesses 6 which connect the tapered recesses 5 to each other.
The spherical shell 3 may be fabricated from a pair of hemispherical portions, each portion being provided with a plurality of holes 7 through which the collars 4 extend. One end of the collar 4 is formed with a flange 4a which bears against the interior surface of the spherical shell 3. As the collar 4 is moved outwardly through the hole 7, flange 4a contacts the inner surface of the spherical shell 3. In order to hold the collar 4 in this location, a metal or rubber stop ring 8, located on an exterior surface of the collar 4 and extending outwardly therefrom is provided.
After attaching the collars 4 to the hemispherical portions of the spherical shell 3, the hemispherical portions are joined together to constitute the spherical shell 3. Using this spherical shell 3 as a core, concrete is molded around the outer surface of the spherical shell 3 to form the ball member 2.
The portion of the collar 4 extending exteriorly of the surface of the ball member 2 defines an opening 4c through a lateral portion thereof which communicates with the hollow interior, and an opening 4b formed on an end surface and extending from one side thereof so as to communicate with the lateral opening 4c as well as the hollow interior of the collar 4.
The bar member, as illustrated in FIG. 2, comprises a hollow concrete cylindrical bar 9, a metallic tension rod 10 extending through the hollow interior of the bar 9 and a socket member 11 fitted into the end of the cylindrical bar 9. A resiliently elastic member 12, made from rubber or the like, has a generally cylindrical configuration and is attached to the socket member 11. A distal end of the resilient member 12 is covered by a metallic cup member 13 which is configured to fit within a tapered recess 5 formed on the outer surface of the ball member 2. Cup member 13 and socket member 11 are fastened together by a plurality of bolts 14 and nuts 15.
Tension rod 10 has an enlarged end portion 16 formed thereon configured to pass through the opening 4c formed in the collar 4 and to engage an inner end portion of the collar 4. Projection 16a is located adjacent to the enlarged portion 16 and is configured so as to engage the opening 4b formed on the end surface of the collar 4 so as to prevent relative rotation between the tension rod 10 and the collar 4.
As best illustrated in FIG. 2, the tension rod 10 may be divided into rod portions 10A and 10B, respectively, and connected together by turnbuckle 17. As is well known in the art, turnbuckle 17 threadingly engages ends of rod portions 10A and 10B such that rotation of the turnbuckle relative to the rod portions causes the rod portions to either move away from each other or toward each other. Turnbuckle 17 has a bevel gear 18 formed thereon to facilitate the rotation of the turnbuckle 17 from the exterior of the bar member 1.
In order to rotate the turnbuckle 17, a turning tool 20 is inserted through elongated opening 19a formed in the concrete cylinder 9 which opening is located so as to facilitate access to the bevel gear 18. A support tool 21 is inserted through elongated opening 19a, located generally diametrically opposite opening 19a, so that the end of rod portion 10A is fitted into, and held in recess 22a defined by support block 22 on the support tool 21, as is best illustrated in FIG. 4. The width a of the support block 22 is less than the length of the elliptical opening 19b and the thickness t is less than the width of the opening 19b so that the support rod can be passed through this opening into the interior of the concrete cylinder 9.
Turning tool 20 comprises a shaft 23 having a handle 24 attached thereto, the end of shaft 23 being formed into a bevel gear 25 for engagement with the bevel gear 18 of the turnbuckle 17. The shaft 23 extends through a bearing member 26 having projections 26a for engaging corresponding recesses 22b formed in the top surface of the support block 22.
The dimensional relationship between the bearing member 26 and the elliptical opening 19a is similar to that of the dimensioned relationship between the support block 22 and the opening 19a previously described. Thus, the bearing member 26 may be easily inserted through the opening 19a and, once inserted, need be turned only 90° to be aligned with the support block 22. Once the tools are positioned as illustrated in FIGS. 2 and 4, it can be seen that rotation of shaft 23 will cause rotation of the turnbuckle 17 through the interengagement of bevel gears 18 and 25. Rotation of the rod portions is prevented by the engagement of projection 16a with the opening 4b formed in the end of collar 4. By rotating the turnbuckle 17, the overall length of the tension rod 10 may be easily adjusted.
In order to assemble the bar member 1 to the ball member 2, length of the bar member 1 is reduced by turning the nuts 15 so as to move the cup member 13 towards the socket member 11 as indicated in dashed lines in FIG. 2. This moves the distal end of the cup member 13 away from the enlarged portion 16 of the tension rod 10, thereby enabling the enlarged portion 16 to be inserted laterally through the opening 4c into the collar 4. The projection 16a engages the opening 4b in order to prevent rotation of the tension rod 10 relative to the collar 4.
Following this insertion, the nuts 15 are again turned so as to enable the cup member 13 to enter the tapered recess 5. The cup member 13 is urged in this direction as the nuts 15 are loosened due to the resiliency of resilient member 12. The nuts 15 and bolts 14 are then removed completely so that the tension rod 10 is held in engagement with the collar 4 by means of the compressive force of the resilient member 12. To complete the assembly, turnbuckle 17 is rotated so as to adjust the length of the tension rod 10 as necessary.
By repeating the foregoing assembly process, the truss structure may be easily assembled. In the truss structure, the tensile forces acting on the bar member 1 are borne by the tension rod 10, while compression forces are borne by the concrete cylinder 9. Impact forces acting on the truss structure are absorbed or alleviated by the resilient member 12.
By using high tensile strength materials to fabricate the spherical shell 3, the spherical shell functions as a strength member such that tensile forces act on the spherical shell so as to increase the tensile strength of the ball member 2.
A second embodiment of the present invention is illustrated in FIGS. 6-8. Elements of this embodiment having the same or similar functions to those elements of the previously described embodiment have been given the same identifying numerals.
The ball member 2 is formed similarly to the ball member of the previously described embodiment wherein a spherical shell 3 is embedded in a concrete covering. However, instead of hollow, collar members 4, this embodiment utilizes a shaft member 31 attached to the spherical shell 3 by an enlarged flange and a stop ring as in the previously described embodiment. The portion of shaft member 31 extending exteriorly of the ball member 2 is threaded.
Tension rod 10 has enlarged portion 16 formed on the end thereof which portion engages nut collar 32. Nut collar 32 has a generally hollow configuration with threads formed on an internal surface adapted to engage the threads formed on the end of shaft member 31. The nut collar 32 defines, on an external surface, a pair of axially extending recesses 32a located generally on diametrically opposite sides of the nut collar 32, as illustrated in FIG. 7. Cup member 13 has projections 13a extending therefrom and located so as to slidably engage the recesses 32a. As can best be seen in FIG. 8, the nut collar 32 is attached to the cup member 13 with snap ring 33 which prevents the axial disengagement of these elements. The cup member 13 is capable of moving a distance ΔS relative to the nut collar 32, the distance ΔS being between a rear surface of the cup member and the end of the recesses 32a. Thus, while slight axial movement between the nut collar 32 and the cup member 13 is allowed, these elements must rotate together due to the interengagement of the projections 13a with the recesses 32a.
In order to assemble the elements of this embodiment, the cup member 13 is moved to the position shown in dashed lines in FIG. 6 toward the socket member 11 by tightening nuts 15 on bolts 14. After locating the bar member 1 adjacent to the ball member 2, nuts 15 are loosened enabling both the cup member 13 and the nut collar 32 to move towards the left, as illustrated in FIGS. 6 and 8. This brings the nut collar 32 into contact with the end of shaft member 31. The nuts 15 and bolts 14 are then completely removed and the cup member 13, along with the nut collar 32 are rotated to thread the nut collar 32 onto the shaft member 31. When the bar member 1 is joined to the ball member 2 in this way, the nut collar 32 can only move a distance ΔS when the cup member 13 is in contact with the ball member 2. Such continued turning movement after contact between the cup member 13 and the ball member 2 moves the nut collar 32 relative to the cup member 13 so as to adjust the tension in the tension rod 10. Thus, the length of the tension rod 10 can easily be adjusted if its length is set slightly shorter than the specified distance between the opposite ball members 2.
In this embodiment, since the spherical shell 3 is embedded in the ball member 2, it serves to reinforce the ball member against tensile forces, as in the previous embodiment.
A third embodiment of the present invention is illustrated in FIGS. 9-11. Again, elements having similar functions to those in the previously described embodiments have been given the same numerals. In this embodiment, the ball member 2 comprises the inner spherical shell 3 made of metal or fiber reinforced plastic which is coated with a rubber material extending from the outer surface of the spherical shell 3.
A plurality of shaft members 40 are attached to the spherical shell 3 by enlarged heads and stop rings 41 such that a portion of the shaft member 40 extends externally of the ball member 2, which external portion has external threads thereon. The exterior surface of the rubber coating defines tapered recesses 5 surrounding the exterior portions of the shaft members 40.
A stop member 46 is attached to the exterior portions of shaft members 40 by lock nuts 47 threadingly engaged onto the shaft members 40. The stop member 46 comprises a base cup member 48 and a socket member 49, each having generally radially extending flanges. The base cup member 48 is spaced from the socket member 49 by a spacer collar 50, which may extend around a portion of shaft member 40.
In this embodiment, the bar member 1 comprises a metal pipe, such as steel, and has a flange 51 extending radially from end portions thereof.
To assemble the bar member 1 to the ball member 2 the flange 51 of the bar member is fitted onto a stop member 46 with an annular shim 52 interposed therebetween. The elements are fastened together by means of a plurality of bolts 53 passing through the flange 51, the shim 52 and the flanges of the stop member 46. Nuts 54 engage the bolts 53 in order to retain the elements together.
The center-to-center distance between ball members 2 may be adjusted by changing the thickness of the annular shim 52. This may be accomplished by either adding or subtracting shims, or using shims of different thicknesses. If a bar member 1 is to be assembled to a partially assembled truss structure, the bar member 1 need only be inserted laterally between the two ball members 2 in the direction of arrow 60 in FIG. 10. This insertion is rendered easier because the flange 51 of the bar member 1 and the flanges of the stop member 46 extend generally parallel to each other and are perpendicular to the longitudinal axis of the bar member 1.
A modified form of this embodiment is illustrated in FIG. 11 and may be utilized when the ball member 2 has the spherical shell 3 coated with a cement material, as in the previously described embodiments. In this instance, a resiliently elastic material 56, such as rubber, is interposed between the base cup member 48 and the socket member 49.
This embodiment simplifies the assembly of the truss structures by directly bolting the end of the steel bar member to a stop member secured to the ball member.
The foregoing description is provided for illustrative purposes only and should not be construed as in any way limiting this invention, the scope of which is defined solely by the appended claims. | A joint structure for removably attaching a ball member to an end of a bar member to form a truss structure is disclosed having an engagement member attached to the ball member, which engagement member has an exterior portion extending outwardly of the outer surface of the ball member, and an attachment device associated with the end of the bar member which removably engages the exterior portion of the engagement member. The joint structure according to the present invention may be utilized with bar members with or without tension rods extending through the bar member. The ball structure may be a spherical shell made of metal or fiber reinforced plastic which is located within a hollow concrete sphere. The spherical shell is not removed from the interior of the concrete sphere, but, instead, is used to increase the tensile force resistance of the ball member. The spherical shell may be imbedded in the ball member at the time of forming the concrete ball and can be used as a molding core. | 4 |
BRIEF DESCRIPTION OF THE INVENTION
Pyrano [4,3-c] pyrazoles having the formula ##STR1##and the pharmaceutically acceptable salts thereof, have useful antiinflammatory activity. In formula I, and throughout the specification, the symbols are as defined below.
R 1 can be hydrogen, hydroxy, alkyl, alkoxy, alkylthio, trifluoromethyl, halogen, nitro, cyano, dialkylamino or alkylsulfinyl; and
R 2 can be hydrogen, alkyl, aryl, arylalkyl, ##STR2## wherein X is alkyl or aryl, or A-NR 3 R 4 wherein A is a straight or branched chain alkylene group having 2 to 5 carbon atoms, R 3 can be hydrogen or alkyl, and R 4 can be hydrogen, alkyl, phenyl or phenylalkyl, or R 3 and R 4 together with the nitrogen atom to which they are attached can be ##STR3## wherein Z can be CH 2 , oxygen or N-R 5 wherein R 5 can be hydrogen, alkyl, aryl or arylalkyl.
The terms "alkyl" and "alkoxy" as used throughout the specification (individually or as part of a larger group) refer to groups having 1 to 8 carbon atoms; alkyl and alkoxy groups having 1 to 3 carbon atoms are preferred.
The term "halogen" as used throughout the specification refers to fluorine, chlorine, bromine and iodine; fluorine and chlorine are preferred.
The term "aryl" as used throughout the specification (individually or as part of a larger group) refers to phenyl or phenyl monosubstituted with an alkyl, alkoxy, halogen or trifluoromethyl group; phenyl is preferred.
DETAILED DESCRIPTION OF THE INVENTION
The compounds of formula I are prepared using as starting materials a substituted tetrahydro-4H-pyran-4-one having the formula ##STR4## and a hydrazine having the formula
H.sub.2 NNH-R.sub.2 III.
the compounds of formulas II and III are readily obtainable; see, for example, Journal of the American Chemical Society, 79:156 (1957) and Journal of Medicinal Chemistry, 7:493 (1964).
A substituted tetrahydro-4H-pyran-4-one of formula II can be prepared by reacting tetrahydro-4H-pyran-4-one with an appropriate benzaldehyde having the formula ##STR5##
A hydrazine of formula III can be prepared by reacting an excess of hydrazine (H 2 NNH 2 ) with a compound having the formula
R.sub.2 -Y V.
wherein Y is chlorine or bromine.
Reaction of a substituted tetrahydro-4H-pyran-4-one of formula II with a hydrazine of formula III yields a product of formula I. The reaction can be run in an organic solvent, preferably a lower alkanol such as methanol. While reaction conditions are not critical, the reaction will preferably be run at, or near, the reflux temperature of the solvent.
Alternatively, compounds of formula I wherein R 2 is hydrogen can be used as intermediates for the preparation of other compounds of formula I, by reaction with alkylating and acylating agents using procedures well known in the art.
Still another method for preparing the compounds of formula I wherein R 2 is A-NR 3 R 4 comprises first reacting a substituted tetrahydro-4H-pyran-4-one of formula II with a hydroxyalkyl hydrazine having the formula
H.sub.2 NNH-A-OH VI.
to form an intermediate having the formula ##STR6##An alcohol of formula VII can be reacted with an alkylsulfonyl or arylsulfonyl halide, preferably p-toluenesulfonyl halide, to yield a compound of the formula ##STR7## wherein Y is alkyl or aryl. The intermediate of formula VIII can be treated with a compound having the formula
HNR.sub.3 R.sub.4 IX.
to yield the products of formula I. This method is particularly useful in preparing those compounds of formula I wherein R 2 is A-NR 3 R 4 , and R 3 and R 4 are both hydrogen.
The compounds of formula I wherein R 2 is aminoalkylene form acid addition salts with inorganic and organic acids. These acid addition salts frequently provide useful means for isolating the products from reaction mixtures by forming the salt in a medium in which it is insoluble. The free base may then be obtained by neutralization, e.g., with a base such as sodium hydroxide. Any other salt may then be formed from the free base and the appropriate inorganic or organic acid. Illustrative are the hydrohalides, especially the hydrochloride and hydrobromide which are preferred, sulfate, nitrate, phosphate, borate, acetate, tartrate, maleate, citrate, succinate, oxalate, benzoate, ascorbate, salicylate, methanesulfonate, benzenesulfonate, toluenesulfonate and the like.
The compounds of formula I, and the pharmaceutically acceptable acid addition salts thereof, are useful in treating inflammation in mammalian species, e.g., rats, dogs, cats, monkeys, etc. Joint tenderness and stiffness (in conditions such as rheumatoid arthritis) are relieved by the above described compounds.
The compounds of this invention can be formulated for use as antiinflammatory agents according to accepted pharmaceutical practice in oral dosage forms such as tablets, capsules, elixirs, or powders, or in an injectable form in a sterile aqueous vehicle prepared according to conventional pharmaceutical practice. The compounds of this invention may be administered in amounts of 100 mg/70kg/day to 2 g/70kg/day, preferably 100 mg/70kg/day to 1 g/70kg/day.
The following examples are specific embodiments of this invention.
EXAMPLE 1
2,3,3a,4,6,7-Hexahydro-3-phenyl-7-(phenylmethylene)-2-propylpyrano[4,3-c]pyrazole
A mixture of 3.6g of tetrahydro-3,5-bis-(phenylmethylene)-4H-pyran-4-one and 1.1g of n-propylhydrazine in 250 ml of methanol is heated at reflux temperature for 3 to 4 hours. Methanol is removed in vacuo, and the residue is dissolved in chloroform. The chloroform solution is washed with dilute hydrochloric acid and water. The organic layer is then dried over anhydrous magnesium sulfate and concentrated in vacuo to give 4g of a crude oil. This is triturated with about 10 ml of acetonitrile and left at room temperature overnight. Some crystals precipitate out and are collected by filtration. The filtrate is concentrated and applied to a dry packed alumina column (neutral, activity I). The fractions eluted with hexane are combined with the crystals obtained above and recrystallized from ether/hexane to yield the title compound, melting point 113.5°-115° C.
EXAMPLES 2-22
Following the procedure of Example 1, but substituting the compound listed in column I for tetrahydro-3,5-bis-(phenylmethylene)-4H-pyran-4-one and the compound listed in column II for n-propylhydrazine, yields the compound listed in column III.
__________________________________________________________________________Example Column I Column II Column III__________________________________________________________________________2 tetrahydro-3,5-bis-[(4-methyl- benzylhydrazine 3-(4-methylphenyl)-7-[(4-methylpheny l)- phenyl)methylene]-4H-pyran-4-one methylene]-2-benzyl-2,3,3a,4,6,7-hex a- hydropyrano[4,3-c]pyrazole3 tetrahydro-3,5-bis-[(4-cyano- ethylhydrazine 3-(4-cyanophenyl)-7-[(4-cyanophenyl) - phenyl)methylene]-4H-pyran-4-one methylene]-2-ethyl-2,3,3a,4,6,7-hexa - hydropyrano[4,3-c]pyrazole4 tetrahydro-3,5-bis-[(4-nitro- n-octylhydrazine 2,3,3a,4,6,7-hexahydro-3-(4-nitrophe nyl)- phenyl)methylene]-4H-pyran-4-one 7-[(4-nitrophenyl)methylene]-2-octyl - pyrano[4,3-c]pyrazole5 tetrahydro-3,5-bis-[[4-(dimethyl- phenylhydrazine 3-[4-(dimethylamino)phenyl]-7-[ [4-(dimethyl- amino)phenyl]methylene]-4H-pyran- amino)phenyl]methylene]-2,3,3a,4,6,7 -hexa- 4-one hydro-2-phenylpyrano[4,3-c]pyrazole6 tetrahydro-3,5-bis-[(3-hydroxy- ethylhydrazine 2-ethyl-2,3,3a,4,6,7-hexahydro-3-(3- hydroxy- phenyl)methylene]-4H-pyran-4- phenyl)-7-[(3-hydroxyphenyl)methylen e]- one pyrano[4,3-c]pyrazole7 tetrahydro-3,5-bis-[(4-methylthio- benzylhydrazine 2-benzyl-2,3,3a,4,6,7-hexahydro-3-(4 -methyl- phenyl)methylene]-4H-pyran-4-one thiophenyl)-7-[(4-methylthiophenyl)m ethylene]- pyrano[4,3-c]pyrazole8 tetrahydro-3,5-bis-[(4-ethylsul- phenylhydrazine 3-(4-ethylsulfinylphenyl)-7-[(4-ethy lsulfinyl- finylphenyl)methylene]-4H-pyran- phenyl)methylene]-2,3,3a,4,6,7-hexah ydro-2- 4-one phenylpyrano[4,3-c]pyrazole9 tetrahydro-3,5-bis-[(2-methyl- methylaminopropyl- 3a,4,6,7-tetrahydro-N-methyl-3-(2- phenyl)methylene]-4H-pyran-4-one hydrazine methylphenyl)-7-[(2-methylphenyl)- methylene]pyrano[4,3-c]pyrazole-2(3H )- propanamine10 tetrahydro-3,5-bis-[ (4-methoxy- N-benzyl-N-methyl- 3a,4,6,7-tetrahydro-N-benzyl-N- phenyl)methylene]-4H-pyran-4-one aminoethylhydrazine methyl-3-(4-methoxyphenyl)-7- [(4-methoxyphenyl)methylene]pyrano- [4,3-c]pyrazole-2(3H)-ethanamine11 tetrahydro-3,5-bis-[(4-trifluoro- N-methyl-N-phenyl- 3a,4,6,7-tetrahydro-N-methyl-N- methylphenyl)methylene]-4H-pyran- aminopentylhydrazine phenyl-3-(4-trifluoromethylphenyl)- 4-one 7-[(4-trifluoromethylphenyl)methyl- ene]pyrano[4,3-c]pyrazole-2(3H)- pentanamine12 tetrahydro-3,5-bis-[(2-chloro- (2-aminoethyl)hydra- 3a,4,6,7-tetrahydro-3-(2-chloro- phenyl)methylene]-4H-pyran-4-one zine phenyl)-7-[2-(chlorophenyl)methylene ]- pyrano[4,3-c]pyrazole-2(3H)-ethanami ne13 tetrahydro-3,5-bis-(phenylmethyl- phenylaminopropyl- 3a,4,6,7-tetrahydro-N-phenyl-3-pheny l- ene)-4H-pyran-4-one hydrazine 7-(phenylmethylene)pyrano[4,3-c]pyra zole- 2(3H)-propanamine14 tetrahydro-3,5-bis-(phenylmethyl- benzylaminopropyl- 3a,4,6,7-tetrahydro-N-benzyl-3-pheny l- ene)-4H-pyran-4-one hydrazine 7-(phenylmethylene)pyrano[4,3-c]pyra zole- 2(3H)-propanamine15 tetrahydro-3,5-bis-[(4-propoxy- 3-(dimethylamino)- 3a,4,6,7-tetrahydro-N,N,β-trime thyl-3- phenyl)methylene]-4H-pyran- 2-methyl-propyl- (4-propoxyphenyl)-7-[(4-propoxypheny l)- 4-one hydrazine methylene]pyrano[4,3-c]pyrazole-2(3H )- propanamine16 tetrahydro-3,5-bis-(phenyl- 3-(4-methyl-1-piper- 2,3,3a,4,6,7-hexahydro-2-[3-(4- methylene)-4H-pyran-4-one azinyl)propylhydrazine methyl-1-piperazinyl)propyl]-3- phenyl-7-(phenylmethylene)pyrano- [4,3-c]pyrazole; melting point 101-104° C; melting point of di- maleate salt 173-175° C17 tetrahydro-3,5-bis-[(4-methyl- 3-(4-methyl-1-piper- 2,3,3a,4,6,7-hexahydro-2-[3-(4- sulfinyl)phenylmethylene]-4H- azinyl)propylhydrazine methyl-1-piperazinyl)propyl]-3- pyran-4-one [4-(methylsulfinyl)phenyl]-7-[4- pyran-4-one [4-(methylsulfinyl)phenyl]-7-[4- (methylsulfinyl)phenylmethylene]- pyrano[4,3-c]pyrazole; melting point of dimaleate salt 172-174° C18 tetrahydro-3,5-bis-(phenyl- 2-(1-piperazinyl)ethyl- 2,3,3a,4,6,7-hexahydro-2-[2-(1- methylene)-4H-pyran-4-one hydrazine piperazinyl)ethyl]-3-phenyl-7- (phenylmethylene)pyrano[4,3-c]- pyrazole19 tetrahydro-3,5-bis-(phenyl- 3-(4-phenyl-1-pipera- 2,3,3a,4,6,7-hexahydro-2-[3-(4- methylene)-4H-pyran-4-one zinyl)propylhydrazine phenyl-1-piperazinyl)propyl]-3- phenyl-7-(phenylmethylene)pyrano- [4,3-c]pyrazole20 tetrahydro-3,5-bis-(phenyl- 4-(4-phenylmethyl-1- 2,3,3a,4,6,7-hexahydro-2-[4-(4- methylene-4H-pyran-4-one piperazinyl)butylhydra- phenylmethyl-1-piperazinyl)butyl]- zine 3-phenyl-7-(phenylmethylene)pyrano- [4,3-c]pyrazole21 tetrahydro-3,5-bis-(2-methyl- 3-(4-morpholinyl)propyl- 2,3,3a,4,6,7-hexahydro-2-[3-(4- phenyl)methylene]-4H-pyran-4-one hydrazine morpholinyl)propyl]-3-(2-methyl- phenyl)-7-[(2-methylphenyl)methylene ]- pyrano[4,3-c]pyrazole22 tetrahydro-3,5-bis-(phenyl- 2-(1-piperidinyl)ethyl- 2,3,3a,4,6,7-hexahydro-2-[2-(1-piper - methylene)-4H-pyran-4-one hydrazine idinyl)ethyl]-3-phenyl-7-(phenyl- methylene)pyrano[4,3-c]pyrazole__________________________________________________________________________ | Compounds having the formula wherein R 1 is hydrogen, hydroxy, alkyl, alkoxy, alkylthio, trifluoromethyl, halogen, nitro, cyano, dialkylamino or alkylsulfinyl; and R 2 is hydrogen, alkyl, aryl, arylalkyl, acyl or an aminoalkylene have useful antiinflammatory activity. | 2 |
CROSS REFERENCE TO PROVISIONAL APPLICATION
[0001] This application claims priority to provisional application No. 60/457,764 filed Mar. 26, 2003
BACKGROUND OF THE INVENTION
[0002] The invention relates to a toggle bolt which can advantageously be used to secure a threaded insert on a mold wall before filling the mold with concrete. This is desired so as to locate the threaded insert in a particular location in the resulting precast article.
[0003] Positioning of various articles into the material of a molded articles is frequently complicated and difficult, and involves various labor-intensive steps in connection with securing the article relative to the mold and, then, removing any extraneous articles after the molded article has at least partially solidified.
[0004] It is the primary object of the present invention to resolve these problems and provide an apparatus whereby an article, especially a threaded insert, can easily be positioned for incorporation into a molded article.
[0005] Other objects and advantages of the present invention will appear hereinbelow.
SUMMARY OF THE INVENTION
[0006] In accordance with the present invention, a toggle bolt is provided which has a threaded portion adapted for threadedly securing with a threaded insert or other threaded article to be incorporated into the molded article, and also having a head portion adapted to be secured to the wall of the mold. Advantageously, the head portion and threaded portion of the toggle bolt is adapted for easy breakaway of one component from the other such that, when the mold wall is removed from the article, the head portion breaks away leaving the threaded insert disposed within the molded article as desired, with the threaded portion of the toggle bolt disposed within the insert.
[0007] In further accordance with the present invention, a toggle bolt is provided for securing a threaded member relative to a mold wall for a molded article, which toggle bolt comprises a head portion having a central portion, a rounded end extending from one end of the central portion and at least one wing flexibly extending laterally with respect to a longitudinal axis of the central portion; and a thread protector portion comprising a threaded member having a slotted head, the thread protector being releasably connected to the central portion.
[0008] In further accordance with the invention, a method is provided for positioning a threaded member in a molded article, comprising the steps of providing a toggle bolt for securing a threaded member relative to a mold wall, comprising a head portion having a central portion, a rounded end extending from one end of the central portion and at least one wing flexibly extending laterally with respect to a longitudinal axis of the central portion; and a thread protector portion comprising a threaded member having a slotted head, the thread protector being releasably connected to the central portion; threading the threaded member onto the thread protector, inserting the head portion into a mold wall of a mold for the molded article, pouring material into the mold so as to form the molded article around the threaded member; and removing the molded article from the mold whereby the head portion breaks away from the thread protector, and the thread protector remains in the threaded member with the slotted head exposed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] A detailed description of preferred embodiments of the present invention follows, with reference to the attached drawings, wherein:
[0010] [0010]FIG. 1 illustrates a toggle bolt and threaded insert in accordance with the present invention;
[0011] [0011]FIG. 2 illustrates a toggle bolt and threaded insert in accordance with the present invention partially inserted through a hole in a mold wall;
[0012] [0012]FIG. 3 illustrates a toggle bolt and threaded insert in accordance with the present invention which is tightened onto the wall of the mold;
[0013] [0013]FIG. 4 illustrates the threaded insert with a portion of the toggle bolt disposed within a molded article, with the mold wall removed from the article and the head portion of the toggle bolt broken away;
[0014] [0014]FIG. 5 illustrates an end view of the threaded insert with threaded portion of the toggle bolt as disposed within a molded article;
[0015] [0015]FIG. 6 is a side view of a preferred embodiment of a toggle bolt in accordance with the present invention; and
[0016] [0016]FIG. 7 is a perspective view of a broken away threaded portion of the embodiment of FIG. 6.
DETAILED DESCRIPTION
[0017] The apparatus in accordance with the present invention further provides for a breakaway portion which leaves a thread protector in the threaded insert after the precast article is removed from the mold. FIGS. 1-5 illustrate a preferred embodiment.
[0018] Referring to FIG. 1, a toggle bolt 10 in accordance with the present invention is shown partially threaded into an insert 12 .
[0019] Toggle bolt 10 according to the invention includes a thread protector portion 14 and a head portion 16 which are releasably connected.
[0020] Thread protector portion 14 is preferably a substantially cylindrical-shaped member having threads for matingly inserting into insert member 12 , and further preferably having a slotted face 18 which, when head portion 16 is removed, allows for removal and replacement using conventional tools such as a simple screw driver.
[0021] Of course, although the illustration of the drawings shows a single slot in thread protector portion 14 , which of course would be useful with a conventional flat screw driver, other structure could be positioned on the surface of thread protector portion 14 which is to be exposed, for interacting with different types of tools or implements as well.
[0022] Head portion 16 is preferably provided having a substantially rounded tip 20 and wing members 22 which are preferably biased to a partially open position as shown in FIG. 1 and which can be inwardly flexed to the position of FIG. 2 so as to allow head portion 16 to be inserted through an opening 24 in a mold wall 26 .
[0023] In use, toggle bolt 10 is threaded into a threaded insert 12 as shown in FIG. 1, and is then pushed, for example by hand, through opening 24 in mold wall 26 as shown in FIG. 2. When the wing members 22 of head portion 16 snap open behind mold wall 26 , for example as shown in FIG. 3, the insert member 12 is then preferably hand tightened against mold wall 26 and the assembly is now properly installed on mold wall 26 such that concrete can be poured into the mold to form a precast article around threaded insert 12 as shown in FIG. 4. When the product is stripped from the mold or form, or vice versa, head portion 16 breaks away from thread protector 14 leaving insert 12 mounted within precast article 28 as desired and as shown in FIG. 4. FIG. 5 further illustrates the final product, with thread protector 14 mounted in threaded insert 12 with slotted face 18 exposed for use in removing thread protector 14 as desired.
[0024] Toggle bolt 10 in accordance with the present invention is preferably provided of any suitable material, for example any of a number of suitable plastic materials, which provide for the desired flexibility of wing members 22 relative to head portion 16 along with the desired breakability in the connection between head portion 16 and thread protector 14 .
[0025] Referring to FIGS. 1-5 together, it is preferred that head portion 16 be provided having a central body portion 30 with a substantially solid base portion 32 and with wing members 22 extending rearwardly, towards base portion 32 , from rounded tip 20 . Central body portion 30 advantageously serves to fill opening 24 in mold wall 26 so as to provide stability of mounting of the device, and further to provide improved seal so as to prevent escape of concrete during filling of the mold.
[0026] This represents a substantial improvement over conventional methods for securing threaded inserts to walls of concrete molds or forms.
[0027] Turning now to FIGS. 6 and 7, an alternative embodiment is illustrated.
[0028] [0028]FIG. 6 shows a toggle bolt 10 similar to that of FIGS. 1-5 having elements as referenced above. In this embodiment, however, a plurality of ridges 50 are advantageously positioned on an outer surface of wings 22 and advantageously serve to assist in holding head portion 16 within an opening in a mold wall as desired. Ridges 50 can be positioned along an outer surface of either or both of wings 22 as desired.
[0029] [0029]FIG. 6 further illustrates an embodiment in accordance with the present invention wherein wings 22 do not extend rearwardly from head 20 , but rather wherein wings 22 are flexibly mounted to body portion 30 at hinged connection points 52 which are shown in the drawings. Connection points 52 are advantageously positioned sufficiently close to head 20 that the trailing edges of wings 22 are sufficiently flexible to allow deflection as the toggle bolt 10 is being positioned into a hole into a mold wall. This connection also further advantageously allows inward flexing of the leading portions 54 of wings 22 to assist in initial entry of this portion of the toggle bolt into an opening in the mold wall as well. Thus, due to connection point 52 , wing portions 22 can first flex inwardly at the lead portions 54 during initial entry into the opening, and then trailing edges of wings 22 can deflect inwardly as the toggle bolt is positioned further into the opening.
[0030] In further accordance with the invention, a slot 56 can advantageously be provided in head portion 16 of toggle bolt 10 , and this slot 56 advantageously serves to conserve material and further provide additional flexibility of wings 22 as desired.
[0031] Still referring to the embodiment of FIG. 6, thread protector 14 is as described above, and can further advantageously be provided having a cut-out 58 in the body portion thereof, which can extend longitudinally along a substantial portion of the length of thread protector 14 as shown. The cut-out 58 should not extend all the way to slot 18 , since this would allow concrete into the threaded insert during molding, which is not desired. Cut-out 58 advantageously serves to conserve material from which toggle bolt 10 is made, and also provides a sharp edge along a portion of the threads of thread protector 14 , which can advantageously scrape any debris or any other material from the inside surface of the threaded insert, whereby positioning thread protector 14 into and out of the threaded member can advantageously clean the threads of same.
[0032] [0032]FIG. 7 further illustrates the structure discussed above in connection with thread protector 14 , and further shows slotted head 18 , cut-outs 58 and the threads of thread protector 14 which are used to threadly engage the insert member as desired.
[0033] It should of course be appreciated that the embodiment shown and described herein is a description of one embodiment of the present invention, and modification as to various shapes and sizes of particular elements of the device can of course be made by a person of ordinary skill in the art well within the scope of the present invention. | A toggle bolt for securing a threaded member relative to a mold wall, including a head portion having a central portion, a rounded end extending from one end of the central portion and at least one wing flexibly extending laterally with respect to a longitudinal axis of the central portion; and a thread protector portion including a threaded member having a slotted head, the thread protector being releaseably connected to the central portion. | 5 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. provisional application No. 60/758,494 filed Jan. 12, 2006, and that application is hereby incorporated by reference as if fully disclosed herein.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to an apparatus for sewing fabrics and attaching rings to fabrics wherein the fabrics are, for example, usable in coverings for architectural openings and more particularly to an apparatus that takes a single or multi-ply sheet of material and either forms hems, tunnels, hobbles, and/or attaches rings to the material so it is suitable for connection to a control system for a covering for an architectural opening.
[0004] 2. Description of the Relevant Art
[0005] While early forms of coverings for architectural openings consisted principally of draped fabrics or fabrics which were gathered along a top edge so as to form drapery, in recent years designer window coverings have taken on many numerous forms. Included in those forms are coverings that utilize fabric that can be raised or lowered and gathered in the process wherein rings or other guide systems are incorporated into the fabric to slidably confine lift cords or the like. Further, in Roman shade type products, horizontal droops in the fabric, otherwise referred to as hobbles, might be formed in the fabric for aesthetics.
[0006] While sewing machines have been used to form hobbles or attach rings to fabric, it was all hand operated with an operator literally moving and shifting the fabric as it was passed through an appropriate sewing machine for either stitching the fabric to provide hems or tunnels across the width of the fabric or to attach suitable guide rings.
[0007] There has, accordingly, been a need in the industry for automating the fabrication of fabric for use in coverings for architectural openings or in the use of fabrics that might have other uses wherein stitching, hobbles, the attachment of rings, or the like, is a requisite.
[0008] Other aspects, features, and details of the present invention can be more completely understood by reference to the following detailed description of the preferred embodiment, taken in conjunction with the drawings and from the appended claims.
SUMMARY OF THE INVENTION
[0009] The apparatus of the present invention includes a vertically oriented and adjustable lift rack to which a top edge of a fabric material can be secured with the remainder of the material hanging by gravity through a lower housing where various clamps are utilized to control the fabric during operations thereon.
[0010] A sewing carriage including a pair of tandem sewing machines having different capabilities are mounted together for movement in unison in a reciprocal path back and forth across the width of the fabric. One sewing machine is adapted to stitch the fabric from one side edge to the other while the other sewing machine is adapted to attach horizontally spaced rings to the fabric in a return movement of the sewing machines across the width of the fabric. When stitching the fabric which might be a dual layer or dual panel fabric, the layers can be handled separately so that one layer might have hobbles formed therein while the other layer remains flat. Tunnels are also defined by the stitching in which rigidifying bars might be inserted. When forming tunnels and/or attaching guide rings to the fabric, a tucker blade is utilized to advance a horizontal section of the fabric into a position for engagement by the sewing machines with the tucker blade being retractable before stitching or the attachment of rings to the fabric. A vacuum chamber is also utilized to gather a horizontal segment of one layer of the fabric to form a hobble while the other layer is unaffected by the vacuum so that both layers can be stitched together with a hobble being formed in one layer.
[0011] A lower releasable clamp positioned beneath the sewing machines has three distinct positions with an open position permitting the free passage of at least a layer of material therethrough, a soft clamp position providing some resistance to movement of the fabric with brushes for removing lint wrinkles or the like from the fabric and a hard clamp position where the fabric can be positively gripped during a sewing operation.
[0012] When the sewing machines have completed one operation of stitching, forming hobbles and/or sewing rings to the fabric, they are repositioned at a home position so the fabric can be elevated a predetermined amount for a repeat of the afore-described operation whereby vertically adjacent rows of hobbles, tunnels, rings, or the like, are formed in the fabric until the entire fabric has been treated. It can then be removed from the lift rack and is suitable for attachment to a control system for a covering for an architectural opening in which the fabric forms an integral part.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a diagrammatic fragmentary isometric of the apparatus of the present invention.
[0014] FIG. 2 is a front isometric of a fabric formed from the apparatus of FIG. 1 .
[0015] FIG. 3 is a rear isometric of the fabric shown in FIG. 2 .
[0016] FIG. 4 is an isometric similar to FIG. 1 showing the sewing machines separated as they might be for maintenance purposes.
[0017] FIG. 5 is a diagrammatic isometric of the apparatus illustrating a first step in treating a fabric.
[0018] FIG. 6 is a diagrammatic isometric similar to FIG. 5 showing a second step in the treatment of a fabric.
[0019] FIG. 7 is a diagrammatic isometric similar to FIG. 6 showing a third step in the treatment of a fabric.
[0020] FIG. 8 is a diagrammatic isometric similar to FIG. 7 showing a fourth step in the treatment of a fabric.
[0021] FIG. 9 is a diagrammatic isometric similar to FIG. 8 showing a fifth step in the treatment of a fabric.
[0022] FIG. 10 is a diagrammatic isometric similar to FIG. 9 showing a sixth step in the treatment of a fabric.
[0023] FIG. 11 is a diagrammatic isometric similar to FIG. 10 showing a seventh step in the treatment of a fabric.
[0024] FIG. 12 is a diagrammatic isometric similar to FIG. 11 showing an eighth step in the treatment of a fabric.
[0025] FIG. 13 is an enlarged diagrammatic fragmentary section taken along line 13 - 13 of FIG. 5 .
[0026] FIG. 14 is an enlarged diagrammatic fragmentary section taken along line 14 - 14 of FIG. 7 .
[0027] FIG. 15 is a section similar to FIG. 14 showing the vacuum chamber advanced into a clamping position with the fabric.
[0028] FIG. 16 is a section similar to FIG. 15 with the vacuum chamber having drawn the fabric thereinto.
[0029] FIG. 17 is a section similar to FIG. 16 with one layer of fabric having been gripped by a lower clamp and removed from the vacuum chamber.
[0030] FIG. 18 is an enlarged diagrammatic section taken along line 18 - 18 of FIG. 8 .
[0031] FIG. 19 is a section similar to FIG. 18 with the tucker blade having been tilted.
[0032] FIG. 20 is an enlarged diagrammatic fragmentary section taken along line 20 - 20 of FIG. 9 .
[0033] FIG. 21 is an enlarged diagrammatic fragmentary section taken along line 21 - 21 of FIG. 10 .
[0034] FIG. 22 is a diagrammatic section similar to FIG. 21 showing hobbles and rings having been formed in the fabric in a plurality of horizontal rows.
[0035] FIG. 23 is an enlarged fragmentary section taken along line 23 - 23 of FIG. 20 .
[0036] FIG. 24 is a section taken along line 24 - 24 of FIG. 23 .
[0037] FIG. 25 is an enlarged fragmentary section taken along line 25 - 25 of FIG. 21 .
[0038] FIG. 26 is a fragmentary section taken along line 26 - 26 of FIG. 25 .
[0039] FIG. 27 is a section similar to FIG. 25 showing the ring and fabric having been shifted for receipt of the sewing needle within the ring.
[0040] FIG. 28 is a section taken along line 28 - 28 of FIG. 27 .
[0041] FIG. 29 is a fragmentary section taken along line 29 - 29 of FIG. 14 showing the lower clamp in a soft clamping position.
[0042] FIG. 30 is a section similar to FIG. 29 showing the lower clamp in a full clamping position.
[0043] FIG. 31 is a section similar to FIG. 29 showing the lower clamp in an open position.
[0044] FIG. 32 is a fragmentary section taken along line 32 - 32 of FIG. 14 .
[0045] FIG. 33 is a top plan view of the portion of the apparatus shown in FIG. 32 .
[0046] FIG. 34 is an enlarged fragmentary section taken along line 34 - 34 of FIG. 32 .
[0047] FIG. 35 is a fragmentary section taken along line 35 - 35 of FIG. 26 .
[0048] FIG. 36 is a section taken along line 36 - 36 of FIG. 35 .
[0049] FIG. 37 is a section similar to FIG. 36 showing the ring clamp in an open position.
[0050] FIG. 38 is a section taken along line 38 - 38 of FIG. 14 .
[0051] FIG. 39 is an enlarged fragmentary section similar to FIG. 38 showing the drive mechanism for linearly translating the sewing machines with the view taken at the left end of the apparatus when the sewing machines are positioned at the left end.
[0052] FIG. 40 is a fragmentary section similar to FIG. 39 with the sewing machines positioned at their home position at the right end of the apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0053] Looking first at FIG. 1 , the apparatus 41 of the present invention can be seen to include a housing 42 on which a lift rack 44 is mounted. As will be described hereafter, the housing includes various components of the apparatus for handling fabric that is being treated while the lift rack supports an upper edge of the fabric and is vertically movable to raise or lower the fabric into or out of the housing. As seen in FIGS. 2 and 3 , a completed fabric 46 which could be formed with the apparatus of the present invention is illustrated. It is shown to include a backing or rear layer 48 and a front layer 50 with the front layer secured to the backing layer along horizontal vertically spaced tucks 52 in the fabric in a manner whereby a plurality of vertically aligned horizontally disposed hobbles or droops 54 in the fabric are formed so the fabric resembles a Roman shade. A tunnel 56 can be formed along the top and bottom edges of the fabric for receipt of a stiffening bar (not seen) with the tunnel possibly being formed from two horizontal lines of stitching that are vertically spaced or by folding the edge and with one stitch forming a hemmed edge. The top tunnel would typically be formed in the fabric before the fabric is treated with the apparatus of the present invention. The top edge of the fabric is then supported in the lift rack 44 so the fabric is properly disposed for processing within the apparatus.
[0054] The lift rack 44 consists of a pair of horizontally spaced vertically extending support towers 58 that are interconnected at their top ends to support a horizontal drive shaft 60 and a motor 62 for reversibly rotating the drive shaft. The lift towers have lift cords (not seen) disposed therein with the lift cords being operably connected to opposite ends of a vertically adjustable horizontally extending transverse lift bar 66 which is referred to hereafter as an upper clamp. Reversible rotation of the drive shaft raises or lowers the upper clamp for purposes to be described hereafter.
[0055] The housing 42 includes a number of operative components which will be described hereafter and which are adapted to grip and manipulate a virgin fabric 68 ( FIGS. 5-9 ) to properly position the fabric so that one or both of a pair of sewing machines 70 and 72 mounted on the housing for reciprocal horizontal translating movement can direct sewing operations to the fabric in a preselected manner.
[0056] One of the sewing machines 70 is provided to stitch horizontal lines in the fabric while the other 72 is provided to attach guide rings 74 ( FIGS. 3 , 21 , 22 and 25 - 28 ) commonly found in certain coverings for architectural openings such as Roman Shades. Both sewing machines are conventional for their intended purpose and will therefore only be described broadly hereafter with specific regard to their operation and relationship to the fabric being treated.
[0057] The apparatus is designed to treat virgin fabric 68 in several different ways so the fabric can be formed with a plurality of hobbles 54 , have a plurality of guide rings 74 attached thereto, provided with a plurality of horizontal tunnels 56 on the front or rear of the fabric, and various combinations of the above. The treatments are accomplished in one continuous operation of the apparatus.
[0058] The apparatus is controlled through a conventional computer control module 76 that energizes various pumps, motors, and pneumatic pistons for achieving the various operations performed by the apparatus on the fabric. A detailed description of the software for driving the control module will not be described herein but suffice it to say the various operating mechanisms in the apparatus are controlled from the module and with an appropriate computer-controlled system.
[0059] The sewing machines 70 and 72 are mounted on two interconnected halves 78 and 80 , respectively, of a sewing machine carriage 82 with the halves typically being interconnected so the sewing machines move in unison but can be separated as shown in FIG. 4 for individual maintenance of the machines. One sewing machine 70 in the preferred embodiment is a walking foot/needle feed lock stitch machine used to stitch the fabric in a manner to become clear hereafter and might be for example a Seiko SSH-88LDC-DTFL machine manufactured by Seiko of Japan. The other machine 72 in the preferred embodiment is a conventional button sewing machine which might be for example a Pfaff 3307 button or ring-stitching machine manufactured by Pfaff of Belgium. The ring-stitching machine, while normally being used for sewing buttons, can sew rings of the type used as guide rings 74 on fabrics for coverings for architectural openings wherein the rings are retained in a hopper (not seen) on the machine and fed to the sewing head where they are connected to the fabric. It is not important which of the two sewing machines is on the right or on the left as they both move in unison across the entire width of the fabric being treated.
[0060] The interconnected halves 78 and 80 of the carriage 82 for the sewing machines 70 and 72 are mounted on a horizontally disposed linear bearing or guide track 84 for reciprocal horizontal movement as the carriage, with the sewing machines thereon, is reversibly translated across the width of the housing 42 . The sewing machines on the carriage are typically stationed at a home position at the right end of the apparatus as viewed in FIG. 1 and during one operation on a virgin fabric 68 , the carriage translates to the left for a stitching operation and then back to the right for a ring attaching operation where it remains in its home position until another row of operations is performed on the fabric. Movement of the carriage is accomplished with a tensioned timing belt 86 as best appreciated by reference to FIGS. 1 and 38 - 40 , which is anchored to the housing 42 at opposite ends with fixed brackets 88 . One of the carriage halves 78 has a motor (not seen) that reversibly drives a gear wheel 90 in operative engagement with the timing belt with the timing belt passing across idler pulleys 92 on opposite sides of the driven gear wheel. It can therefore be appreciated that rotation of the gear wheel in one direction causes the carriage 82 to translate linearly in one direction across the apparatus and rotation of the gear wheel in the opposite direction causes the carriage to translate linearly in the opposite direction so it can be moved from one side of the apparatus 41 to the other at predetermined speeds.
[0061] FIGS. 5-12 illustrate diagrammatically the various steps that can be applied to a virgin fabric 68 with the apparatus 41 of the present invention in forming a completed fabric 46 of the type illustrated in FIGS. 2 and 3 . The completed fabric in the example shown includes a plurality of horizontal hobbles or loops 54 formed in vertically adjacent rows on the front layer of the fabric ( FIG. 2 ) and a plurality of horizontally extending vertically spaced tucks 52 having horizontally spaced guide rings 74 secured thereto formed on the rear layer 48 of the fabric as seen in FIG. 3 . Looking first at FIG. 5 , a virgin fabric consisting of two layers of sheet material that have been pretreated to form a tunnel 56 along a top edge thereof with a rigidifying slat (not seen) possibly inserted therein is clamped to the upper clamp 66 . The upper clamp includes a pair of horizontal bars 94 and 96 that can be clamped together or released. In the released position, the top edge of the virgin fabric 68 can be inserted between the bars and in the clamped position releasably secured between the bars. While the fabric could be positioned at any place across the width of the upper clamp, if in fact the fabric were narrower than the width of the lift rack 44 as illustrated, it is preferably positioned along one side edge (illustrated as the right side edge) for a purpose to be more clear hereafter.
[0062] After the virgin fabric 68 is secured to the upper clamp 66 , the upper clamp is elevated with the motor 62 and drive shaft 60 to the position of FIG. 6 so the fabric is substantially vertically suspended with its lower edge at the top of the housing 42 . The upper clamp is then lowered and depending upon the operations to be applied to the virgin fabric, the two layers of the fabric can be maintained together or separated so as to straddle various components within the housing. Once the layers of the fabric are positioned for the operations to be applied thereto within the housing, the upper clamp is lowered to an initial operative position shown in FIG. 7 . Thereafter, a hobble 54 is formed in the front layer 50 and a reciprocating horizontally disposed tucker blade 98 , which will be described in more detail later, is normally in a retracted position adjacent to the front layer of the fabric is advanced as shown in FIG. 18 to form a tuck 52 off the rear of the fabric on which the sewing machines 70 and 72 can operate. The tuck in the fabric is then gripped with a tuck clamp 100 (to be described later) and the tucker blade retracted so a first operation of the sewing machines as shown in FIG. 9 can be initiated with the sewing machines translating from their home position at the right end of the apparatus 41 to the left end of the apparatus. As shown in FIG. 10 , a subsequent pass of the sewing machines from the left end of the apparatus back to their home position allows one of the sewing machines to perform a separate operation. For example, in the fabric 46 illustrated in FIGS. 2 and 3 where both hobbles 54 and guide rings 74 are applied to the fabric, the movement from the home position to the left as shown in FIG. 9 would be used to form a horizontal stitch with one of the sewing machines 70 along the tuck to hold the two layers of material in the tuck together and the reverse movement of the sewing carriage 82 , as shown in FIG. 10 , would be used for attaching the guide rings with the other sewing machine 72 along the edge of the tuck. After one such operation, one row of a tunnel 56 , defined by a tuck, with its associated guide rings is completed along with a hobble and at that time, the upper clamp 66 is elevated a predetermined distance, i.e. the height of a hobble, and the operation is repeated. By repeating the operation a new row is formed and the upper clamp is elevated a predetermined amount as shown in FIG. 11 until the entire fabric 46 has been completed as illustrated in FIG. 12 .
[0063] Referring to FIG. 13 , which is a vertical section through the apparatus 41 with the layers 48 and 50 of virgin fabric having been connected to the apparatus as shown in FIG. 5 with the upper clamp 66 , the internal working components of the apparatus are shown diagrammatically. It will there be seen beneath the upper clamp is the tuck clamp 100 that includes an elongated horizontally disposed generally U-shaped rail 101 extending the width of the apparatus and connected to a pair of pneumatic cylinders 102 mounted at opposite ends of the rail with mounting brackets 104 on the rear face of the rail. A lower edge of the rail carries a beveled strip 106 supporting a spring steel upper clamp jaw 108 with a gripping edge of material 110 secured on its lower face along a distal edge thereof. The pneumatic cylinders 102 are operative to raise or lower the rail and the upper clamp jaw in a manner such that in a lowered position of the tuck clamp, as seen for example in FIG. 19 , the upper clamp jaw engages a tuck 52 of material and presses the material against a platen 112 with a gripping upper surface mounted vertically therebeneath on the housing 42 . In the normal elevated position of the tuck clamp, a space is defined between the upper clamp jaw and the platen through which a tuck in the fabric can be advanced for proper positioning relative to the sewing machine carriage 82 as will be discussed later.
[0064] In horizontal opposing relationship to the tuck clamp rail 101 and positioned horizontally between the pneumatic cylinders 102 and beneath a support plate 114 in the housing is a vacuum clamp 116 . The vacuum clamp includes an elongated horizontally disposed plenum 118 where a low pressure is maintained and a horizontally aligned elongated vacuum chamber 120 communicating with the plenum and having a horizontal slot-like opening 122 in a front wall 124 thereof facing the tuck clamp rail. While the opening 122 extends the full length of the vacuum chamber, an extendable closure tape 126 ( FIGS. 32-34 ) is mounted at one end of the chamber to be selectively extended across a portion of the chamber to close a portion of the opening if the fabric is not wide enough to cover the entire length of the opening. The plenum and vacuum chamber are reciprocally mounted on the plungers 128 of a second pair of pneumatic cylinders 130 secured to the support plate 114 so that when the plungers for the cylinders are extended, the front wall 124 of the vacuum chamber is advanced into engagement with the tuck clamp rail 101 . Of course, retraction of the vacuum chamber with a retraction of the plungers 128 of the second pair of pneumatic cylinders 102 withdraws the chamber and moves it to the left as viewed in FIG. 13 so as to define a space between the rail of the tuck clamp and the vacuum chamber. The plenum for the vacuum chamber is connected with a conventional conduit to a selectively operable vacuum pump 132 positioned within the housing.
[0065] The tucker blade 98 is a horizontal elongated blade of thin profile extending the full width of the apparatus 41 and mounted on a horizontal support plate 133 secured to the rack 134 of a rack and pinion reciprocal drive system 136 ( FIG. 13 ). The pinion 138 of the drive system is reversibly driven by a motor (not seen). Obviously, rotation of the pinion in one direction drives the rack and the tucker blade horizontally to the right as viewed in FIG. 13 into an extended position as seen in FIG. 18 while rotation of the pinion in the opposite direction retracts the tucker blade to its retracted position of FIG. 13 . In the extended position shown in FIG. 18 , it is extended between the upper clamp jaw 108 and platen 112 of the tuck clamp 100 with the front elongated edge 140 of the tucker blade being positioned beyond the tuck clamp immediately adjacent to the sewing carriage 82 . The horizontal support plate 132 on which the tucker blade is mounted is supported on a lever arm 142 pivotal about a pivot shaft 144 by a pair of low-pressure pneumatic cylinders 145 which could in fact be a gas spring even though in the disclosed embodiment it is a pneumatic cylinder carrying low pressure. The pneumatic cylinders are therefore adapted to pivot the lever arm and thus the tucker blade about the pivot shaft for a purpose to become clear hereafter.
[0066] A lower clamp 146 is positioned beneath the tucker blade 98 at an elevation also beneath the platen 112 . The lower clamp has a horizontally movable vertically disposed bar 148 that supports pairs of large 150 and small 152 pneumatic cylinders which are probably best appreciated by reference to FIGS. 29-31 . The movable vertically disposed bar confronts a second vertically disposed bar 154 that is fixedly mounted on a vertically movable support plate 156 . The fixedly mounted bar has an upper horizontal rearwardly directed brush 158 with a plurality of flexible bristles that overlaps a similar elongated horizontally disposed brush 160 mounted on the movable bar 148 . The lower clamp is a three-position clamp and movable between an open position as shown in FIG. 31 wherein the brushes 158 and 160 are not vertically overlapping but rather define a vertical passage therebetween, a soft closed position as shown in FIG. 29 where the brushes partially overlap as seen for example in FIG. 13 as well as FIG. 29 and a fully closed clamping position as shown in FIG. 30 where the lower brush 160 carried by the movable bar is engaged against the fixed bar 154 .
[0067] The plungers 162 of the large cylinders 150 are secured at their distal end to the fixed bar 154 such that extension of the plungers causes the movable bar 148 to retract or move to the left relative to the fixed bar and retraction of the cylinders causes the movable bar to move to the right toward the fixed bar. The plungers 164 on the small cylinders 152 merely extend into the space between the fixed and movable bars regardless of whether or not they are extended or retracted.
[0068] To move the lower clamp 146 between its three positions, and again with reference to FIGS. 29-30 , in the open position of FIG. 31 , the large pneumatic cylinder plungers 162 are fully extended so as to fully separate the two bars 148 and 154 and the brushes 158 and 160 mounted thereon to define a vertical gap between the brushes. The plungers 164 of the smaller cylinders 152 are also fully extended but non-engaging with the fixed bar 154 due to their relatively short length. To move the clamp to the soft clamping position of FIG. 29 , the large cylinder plungers are retracted to pull the movable bar toward the fixed bar until the plungers of the small cylinders engage the fixed bar to fix the spacing between the movable and fixed bars of the lower clamp. To move the lower clamp to its fully closed and full clamping position of FIG. 30 , the plungers on the small cylinders are fully retracted as are the plungers on the large cylinders so the lower brush 160 on the movable bar closely approaches the fixed bar in which position the fabric can be positively gripped for purposes to be described hereafter. A positive grip is best established with a horizontal channel member 166 ( FIG. 19 ) opening off the face of the movable bar 148 and a fixed leg 168 with gripping pads 170 on the fixed bar with the leg being inserted into the channel when the clamp is fully closed.
[0069] The fixed bar 154 , as mentioned previously, is mounted on the support plate 156 that is of L-shaped configuration and itself vertically reciprocably mounted on another pair of pneumatic cylinders 172 , which can elevate the fixed bar and movable bar 148 of the lower clamp 146 to the position of FIG. 13 , for example, or lower the fixed and lower bars of the lower clamp to the position of FIG. 17 .
[0070] Also provided within the housing 42 near the bottom thereof are a pair of support rods 174 that support a flexible cradle 176 of any suitable material in which the virgin fabric 68 can gather when the upper clamp 66 is lowered to the position of FIG. 5 , for example. In fact, with reference to FIG. 14 , a virgin fabric 68 is shown in the position of FIG. 5 and is gathered in the cradle from which it can be removed as the upper clamp is raised during processing of the fabric.
[0071] Referring to FIG. 14 , the apparatus 41 is postured for forming a fabric 46 of the type shown in FIGS. 2 and 3 with hobbles 54 and guide loops 74 and for such a fabric, when the upper clamp 66 is lowered to the position of FIG. 5 , the rear layer 48 of the fabric is threaded through the lower clamp 146 , as shown in FIG. 14 , and the front layer 50 of the fabric is passed on the rear side of the movable bar 148 of the lower clamp so as to bypass the lower clamp. As will be appreciated from the description herein, the reference to the layers of the fabric as front 50 and rear 48 layers, for illustrative purposes, is the reverse of the reference to the parts of the apparatus since the fabric is mounted in the apparatus with its front layer facing the rear of the apparatus. It will also be appreciated in the positioning of the fabric in FIG. 14 , both layers of the fabric pass freely past the tuck clamp 100 and the vacuum clamp 116 and will also slide through the lower clamp even though the lower clamp is in its soft-clamping position with the rear layer of the fabric engaging the upper and lower brushes 158 and 160 of the lower clamp.
[0072] Referring to FIG. 15 , when forming the fabric 46 of FIGS. 2 and 3 , having both hobbles 54 and guide loops 74 , the first step in the operation is to grip the virgin fabric 68 with the vacuum clamp 116 so the fabric is pinched between the vacuum chamber 120 and the tucker rail 101 . The closure tape 126 can be pulled across the opening in the front wall of the vacuum chamber from the left edge of the opening to the left edge of the fabric to maintain adequate vacuum in the chamber. A vacuum is then drawn by energizing the vacuum pump 132 which pulls both layers of fabric into the vacuum chamber as seen in FIG. 16 as the upper clamp 66 is lowered to provide more fabric to the vacuum clamp. Typically, in a fabric of this type, the front layer 50 is less porous than the rear layer 48 so the vacuum is more effective on the front layer but there is enough vacuum to draw both layers into the vacuum chamber.
[0073] With both layers 48 and 50 of the fabric drawn a predetermined amount into the vacuum chamber 120 , which is permitted by the top clamp 66 being lowered a predetermined amount, the lower clamp 146 is moved into its full clamping position as shown in FIG. 17 so the rear layer of the fabric is fully gripped by the lower clamp but the front layer is free to move up or down. Thereafter, as also seen in FIG. 17 , the vacuum clamp 116 is withdrawn and simultaneously the lower clamp is lowered which pulls the rear layer of the fabric out of the vacuum chamber so it is relatively straight while the front layer still forms a loop within the vacuum chamber which will ultimately form a hobble 54 in the fabric.
[0074] Subsequently, as shown in FIG. 18 , the tucker blade 98 is advanced with the rack and pinion system 136 while the tucker blade is in a horizontal orientation which forces both layers 48 and 50 of the fabric between the upper clamp jaw 108 and the platen 112 of the tuck clamp 100 thereby forming a tuck 52 in both layers of the fabric. Before the tucker blade is advanced, however, the lower clamp 146 is moved to its soft clamp position of FIG. 18 so the rear layer of the fabric is drawn through and across the lower clamp and across the brushes 158 and 160 to remove lint and any wrinkles while the front layer of the fabric, which is freely hanging can be moved therewith. When advancing the tucker blade in this manner, it will be appreciated that since both layers of the fabric are gripped by the vacuum clamp 116 , even though only the front layer 50 is drawn into the vacuum chamber 120 , all of the material is fed upwardly from below the tucker blade and therefore the material slides slightly across the leading edge 140 of the tucker blade 98 . If a hobble 54 was not being formed in the fabric during this step, the vacuum clamp would remain in a retracted position and there would be no loop or hobble of the front layer of fabric in the vacuum chamber. Rather, both layers would be in adjacent side-by-side relationship and by lowering the upper clamp as the tucker blade is advancing, equal amounts of material can be pulled downwardly from above the tucker blade as pulled upwardly from below the tucker blade to avoid having to draw the material across the leading edge of the tucker blade which minimizes any opportunity for damage to the fabric.
[0075] Referring to FIG. 19 , with the tucker blade 98 in the position of FIG. 18 , the tuck clamp 100 is lowered so the tuck 52 of fabric with the tucker blade therein is clamped between the upper clamp jaw 108 and the platen 112 of the tuck clamp and due to the bevel or inclination of the upper clamp jaw of the tuck clamp, the tucker blade is tilted which is permitted by pivoting of its support plate 132 about the pivot shaft 144 which is further permitted by the low pressure in the pneumatic cylinders 144 or if the pneumatic cylinders were replaced with a gas spring it would be permitted by the gas spring through minimal resistance to such pivotal movement.
[0076] The tucker blade 98 is coated with Teflon® or another low-friction material so that once the tuck 52 in the material has been gripped by the tuck clamp 100 , the tucker blade can be easily withdrawn, as shown in FIG. 20 , leaving the tuck of fabric positioned between the upper clamp jaw 108 and platen 112 of the tuck clamp. The low-friction coating of the tucker blade allows easy sliding removal of the tucker blade even though the tuck of fabric is positively gripped and held in position.
[0077] In the position of FIG. 20 , the sewing machine carriage 82 is energized so as to translate from the rest position at the right of the apparatus 41 to the left side of the apparatus and as it is making this pass, the stitching sewing machine 70 is activated while the ring-attaching sewing machine 72 is deactivated. The tuck 52 in material, as can be seen in FIGS. 20 and 23 , is aligned with the stitching needle 178 so that as the sewing machine carriage is advanced or translated across the apparatus, a stitch 180 ( FIG. 23 ) is formed in the fabric at a spaced parallel location from the fold 182 at the edge of the tuck. This establishes a tunnel 56 in the tuck between the stitching and the folded edge of the tuck in which a reinforcing bar (not shown) can be placed if desired.
[0078] After the stitch 180 has been formed and the carriage 82 is at the left side of the apparatus, the carriage is then driven to the right. The stitching machine 70 is deactivated and the ring-attaching sewing machine 72 is activated to attach rings 74 at predetermined spaced locations along the width of the fabric and along the folded edge 182 of the tuck 52 . The spacing of the rings is predetermined depending upon the number of rings desired per width of the fabric and this can all be calculated and computed within the control module.
[0079] As mentioned previously, the ring-attaching machine 72 is a conventional button sewing machine which includes a hopper (not seen) for a plurality of buttons or rings 74 and a ramp 184 ( FIG. 21 ) that might vibrate for example that confines a string of rings on a downward sliding path from the hopper to a linearly reciprocating ring gripper 186 as shown in FIGS. 21 , 25 - 28 , and 35 - 37 . In the Pfaff ring-stitching machine used in the preferred embodiment of the invention, the sewing needle 178 on the head of the sewing machine 72 reciprocates up and down at a predetermined position but it is desired to stitch across one edge of a ring 74 so that some of the stitches are outside the ring and others are inside the ring so the ring is positively attached to the folded edge 182 of the tuck 52 . In order to establish the stitching across the ring, the ring gripper reciprocates forwardly and rearwardly shoving the ring and the edge of the fabric into one position for allowing the sewing needle to establish a stitch 188 ( FIG. 27 ) within the ring and then retracting the ring which allows the folded edge to also return therewith so the folded edge of the material is aligned with the needle. Accordingly, the next stitch 188 can go through the folded edge of the fabric. By repeating this operation, a predetermined number of threads secure an edge of the ring to the folded edge of the tuck. Thereafter, the ring-attaching machine is moved linearly toward its rest position until it is stopped by the control module at a location where the next ring is to be attached and the ring is attached at that location in the same manner.
[0080] With reference to FIGS. 25-28 and 35 - 37 , the ring clamp or gripper 186 has two spaced arms 190 with the distance between the spaced arms being adjustable in the Pfaff sewing machine so that in a gripping position shown in FIGS. 25-28 , 35 and 36 , the ring 74 is positively held so it can be advanced or retracted for desired alignment with the sewing needle 178 . After the ring has been attached to the tuck 52 , the arms of the ring clamp are retracted as shown in FIG. 37 and the ring clamp itself retracted so the sewing machine can be linearly advanced toward home base and once reaching its next position of attachment for a ring, the arms 190 receive the next ring in line which is dropped therebetween so it too can be gripped and handled as described previously.
[0081] As will be appreciated from the above, with one complete reciprocal pass of the sewing carriage 82 across the width of the fabric and back, a tunnel 56 can be formed along the edge of the fabric securing the tuck 52 and rings 74 can be attached at predetermined spaced locations to the tuck. On the opposite face or front layer 50 of the fabric, a hobble 54 is formed during the same operation as a loop of the front layer was confined during the operations within the vacuum chamber 120 . Accordingly, a hobble, tunnel and associated rings forming one row of the fabric are established each time the sewing carriage passes through a reciprocating path back and forth across the width of the fabric. After a row has been formed, the upper clamp 66 can be elevated a predetermined distance corresponding to the desired height of a hobble for another identical subsequent operation until a complete fabric 46 has been formed as shown in FIGS. 2 and 3 . Once formed, the fabric is simply removed from the upper clamp where it is ready for incorporation into a control system for the architectural covering in which it is to be incorporated.
[0082] It will be appreciated from the above that by selecting various operations, a fabric 46 with hobbles 54 and guide rings 74 can be formed as described above or a one or more layer fabric can be formed with simply the guide rings by leaving the vacuum clamp 116 in an inoperative or retracted position so the hobbles are not formed. If tucks were desired with rings, both the stitching and ring attaching sewing machines would be used but if no tucks were desired in the finished fabric, a stitch would not be placed in the tuck established by the tucker blade but only rings would be attached at the folded edge established by the tucker blade. Similarly, if the rings were not desired for a fabric but the hobbles were, then the operation would be as described above except in the return path of the sewing carriage 82 , the ring-attaching sewing machine 72 would not be activated so a fabric would be formed with only hobbles.
[0083] If only tunnels 56 were desired for the fabric, the vacuum clamp 116 would again be deactivated or retained in its withdrawn position and the two layers 48 and 50 of the fabric would be handled together with both layers passing through the lower clamp 146 but other than this distinction, the formation of horizontal tunnels at vertically spaced locations would follow the above procedure. Again, however, only the stitching machine 70 would be operative and the ring-attaching machine 72 would be deactivated so that tucks 52 and tunnels were formed off the rear of the fabric along parallel vertically spaced lines. Of course, if the tunnels were desired on the front of the fabric, the virgin fabric 68 could be reversed in the upper clamp 66 so the tunnels were formed on the front of the fabric rather than the rear.
[0084] Clearly from the various options available with the apparatus, fabric for different types of coverings for architectural openings can be made automatically. Further, varying widths of fabrics can be handled up to the spacing of the lift towers on the lift rack.
[0085] Although the present invention has been described with a certain degree of particularity, it is understood the disclosure has been made by way of example and changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims. | An apparatus for forming fabrics for use, by way of example, in coverings for architectural openings includes a system for handling single or multi-layered fabrics by suspending the fabric from a lift tower, threading the fabric through various clamp systems within a housing for the apparatus, and subsequently forming horizontal rows of hobbles, tunnels, and/or attached rings by gripping and releasing the fabric with a vacuum clamp, upper and lower clamps, and a tucker blade clamp while a reciprocating tucker blade forms horizontal tucks in the fabric. The tucks which are selectively treated by forming a tunnel or attaching guide rings. Hobbles can also be formed in one layer of the fabric through use of the vacuum clamp which gathers a portion of one layer of the fabric while the other layer is handled differently. In doing so, hobbles are formed between tucks in the fabric with the hobbles establishing a fabric resembling a Roman shade. | 3 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a continuation of U.S. application Ser. No. 12/862,305, filed Aug. 24, 2010, now U.S. Pat. No. 8,544,079, which is a continuation of U.S. application Ser. No. 11/128,933, filed May 12, 2005, now U.S. Pat. No. 8,127,348, which is a continuation of U.S. application Ser. No. 09/333,829, filed Jun. 15, 1999, now U.S. Pat. No. 6,957,346. The entire contents of all applications are incorporated herein by reference in their entireties.
TECHNOLOGICAL FIELD
The invention relates in general to the field of communications between computers in packet-switched data transmission networks. More particularly the invention relates to the field of communication connections through a Network Address Translation.
BACKGROUND OF THE INVENTION
The Internet Engineering Task Force (IETF) has standardized the IPSEC (Internet Protocol Security) protocol suite; the standards are well known from the Request For Comments or RFC documents number RFC2401, RFC2402, RFC2406, RFC2407, RFC2408 and RFC2409 mentioned in the appended list of references, all of which are hereby incorporated by reference. The IPSEC protocols provide security for the IP or Internet Protocol, which itself has been specified in the RFC document number RFC791.
IPSEC performs authentication and encryption on packet level by generating a new IP header, adding an Authentication Header (AH) or Encapsulating Security Payload (ESP) header in front of the packet. The original packet is cryptographically authenticated and optionally encrypted. The method used to authenticate and possibly encrypt a packet is identified by a security parameter index (SPI) value stored in the AH and ESP headers. The RFC document number RFC2401 specifies a transport mode and a tunnelling mode for packets; the present invention is applicable regardless of which of these modes is used.
In recent years, more and more vendors and Internet service providers have started performing network address translation (NAT). References to NAT are found at least in the RFC document number RFC1631 as well as the documents which are identified in the appended list of references as Srisuresh98Terminology, SrisureshEgevang98, Srisuresh98Security, HoldregeSrisuresh99, TYS99, Rekhter99, LoBorella99 and BorellaLo99. There are two main forms of address translation, illustrated schematically in FIGS. 1 a and 1 b : host NAT 101 and port NAT 151 . Host NAT 101 only translates the IP addresses in an incoming packet 102 so that an outgoing packet 103 has a different IP address. Port NAT 151 also touches the TCP and UDP port numbers (Traffic Control Protocol; User Datagram Protocol) in an incoming packet 152 , multiplexing several IP addresses to a single IP address in an outgoing packet 153 and correspondingly demultiplexing a single IP address into several IP addresses for packets travelling in the opposite direction (not shown). Port NATs are especially common in the home and small office environment. The physical separation of input and output connections for the NAT devices is only shown in FIGS. 1 a and 1 b for graphical clarity; in practice there are many possible ways for physically connecting a NAT.
Address translation is most frequently performed at the edge of a local network (i.e., translation between multiple local private addresses on one hand and fewer globally routable public addresses on the other). Most often, port NAT is used and there is only one globally routable address. A local network 154 has been schematically illustrated in FIG. 1 b . Such arrangements are becoming extremely commonplace in the home and small office markets. Some Internet service providers have also started giving private addresses to their customers, and perform address translation in their core networks for such addresses. In general, network address translation has been widely discussed in depth e.g. in the NAT working group within the Internet Engineering Task Force. The operating principles of a NAT device are well known, and there are many implementations available on the market from multiple vendors, including several implementations in freely available source code. The typical operation of a NAT may be described so that it maps IP address and port combinations to different IP address and port combinations. The mapping will remain constant for the duration of a network connection, but may change (slowly) with time. In practice, the NAT functionality is often integrated into a firewall or a router.
FIG. 1 c illustrates an exemplary practical network communication situation where a transmitting node 181 is located in a first local area network (also known as the first private network) 182 , which has a port NAT 183 to connect it to a wide-area general packet-switched network 184 like the Internet. The latter consists of a very large number of nodes interconnected in an arbitrary way. A receiving node 185 is located in a second local area network 186 which is again coupled to the wide-area network through a NAT 187 . The denominations “transmitting node” and “receiving node” are somewhat misleading, since the communication required to set up network security services is bidirectional. The transmitting node is the one that initiates the communication. Also the terms “Initiator” and “Responder” are used for the transmitting node and the receiving node respectively.
The purpose of FIG. 1 c is to emphasize the fact that the communicating nodes are aware of neither the number or nature of the intermediate devices through which they communicate nor the nature of transformations that take place. In addition to NATs, there are other types of devices on the Internet that may legally modify packets as they are transmitted. A typical example is a protocol converter, whose main job is to convert the packet to a different protocol without disturbing normal operation. Using them leads to problems very similar to the NAT case. A fairly simple but important example is converting between IPv4 and IPv6, which are different versions of the Internet Protocol. Such converters will be extremely important and commonplace in the near future. A packet may undergo several conversions of this type during its travel, and it is possible that the endpoints of the communication actually use a different protocol. Like NAT, protocol conversion is often performed in routers and firewalls.
It is well known in the IPSEC community that the IPSEC protocol does not work well across network address translations. The problem has been discussed at least in the references given as HoldregeSrisuresh99 and Rekhter99.
In the Finnish patent application number 974665 and the corresponding PCT application number FI98/01032, which are incorporated herein by reference, we have presented a certain method for performing IPSEC address translations and a method for packet authentication that is insensitive to address transformations and protocol conversions en route of the packet. Additionally in said applications we have presented a transmitting network device and a receiving network device that are able to take advantage of the aforementioned method. However, some problems related to the provision of network security services over network address translation remain unsolved in said previous patent applications.
SUMMARY OF THE INVENTION
It is an object of the present invention to present a method and the corresponding devices for providing network services over network address translation in a reliable and advantageous way.
According to a first aspect of the invention, there is provided a method comprising receiving, by a computer device, a packet comprising a predetermined value indicating support by a node for an extension of a communications protocol, wherein the communications protocol is used for communications across a network translator device and the extension is capable of traversing network address translation, and in response to said receiving, determining that the node sending the packet supports the extension of the communications protocol.
According to a second aspect of the invention, there is provided an apparatus comprising at least one processor, and at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processor, receive a packet comprising a predetermined value indicating support by a node for an extension of a communications protocol, wherein the communications protocol is used for communications across a network translator device and the extension is capable of traversing network address translation, and in response to said received packet, determine that the node sending the packet supports the extension of the communications protocol.
According to a third aspect of the invention, there is provided non-transitory computer readable media, comprising program code program code for causing a processor to perform instructions for receiving, by a device, a packet comprising a predetermined value indicating support by a node for an extension of a communications protocol, wherein the communications protocol is used for communications across a network translator device and the extension is capable of traversing network address translation, and in response to said receiving, determining that the node sending the packet supports the extension of the communications protocol.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 a illustrates the known use of a host NAT,
FIG. 1 b illustrates the known use of a port NAT,
FIG. 1 c illustrates a known communication connection between nodes through a packet-switched network,
FIG. 2 a illustrates a certain Vendor ID payload applicable within the context of the invention,
FIG. 2 b illustrates a certain private payload applicable within the context of the invention,
FIG. 2 c illustrates a certain combined header structure applicable within the context of the invention,
FIG. 3 illustrates certain method steps related to the application of the invention,
FIG. 4 illustrates a transformation of header structures according to an aspect of the invention, and
FIG. 5 illustrates a simplified block diagram of a network device used to implement the method according to the invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention combines and extends some of the methods of network address translation, tunneling over UDP, IKE, and the IKE extension mechanisms, in a novel and inventive way to produce a method for secure communications across network address translations and protocol conversions. The method can be made fully automatic and transparent to the user.
A key point relating to the applicability of the invention is that—at the priority date of the present patent application—in general only TCP (described in RFC793, which is hereby incorporated by reference) and UDP (described in RFC768, which is hereby incorporated by reference) work over NAT. This is because most NATs used in practise are port NATs, and this is the form of NAT that provides most benefits with regards to the shortage of globally routable IP addresses. The invention is not, however, limited to the use of UDP and TCP as they are known at the priority date of this patent application: in general it may be said that UDP and TCP are examples of protocols that determine that connection identification information (i.e. addressing and port numbering) that is mapped into another form in the address transformation process. We may expect that other kinds of communication protocols and address transformations emerge in the future.
The various aspects of the invention are related to
determining whether a remote host supports a certain method which is typically a secure communication method according to the invention (the “methods supported” aspect), determining what network address translations and/or protocol conversions occur on packets, if any (the “occurring translations” aspect), tunneling packets inside a certain carefully selected protocol, typically UDP, to make them traverse NATs (the “selected tunnelling” aspect), using a keepalive method to make sure that involved NAT devices and other devices that use timeouts for mappings do not lose the mapping for the communicating hosts (the “keepalive” aspect), compensating for the translations that occur before verifying the message authentication code for AH packets (the “compensation/authentication” aspect) and performing address translations at either the sending or receiving node to compensate for multiple hosts being mapped to a single public address (the “compensation/mapping” aspect).
The process of encapsulating data packets for transmission over a different logical network is called tunneling. Typically, in the case of the IP protocol, tunneling involves adding a new IP header in front of the original packet, setting the protocol field in the new header appropriately, and sending the packet to the desired destination (endpoint of the tunnel). Tunneling may also be implemented by modifying the original packet header fields or replacing them with a different header, as long as a sufficient amount of information about the original packet is saved in the process so that it will be possible to reconstruct the packet at the end of the tunnel into a form sufficiently similar to the original packet entering the tunnel. The exact amount of information that needs to be passed with the packet depends on the network protocols, and information may be passed either explicitly (as part of the tunnelled packet) or implicitly (by the context, as determined e.g. by previously transmitted packets or a context identifier in the tunneled packet).
It is well known in the art how to tunnel packets over a network. At least the references given as RFC1226, RFC1234, RFC1241, RFC1326, RFC1701, RFC1853, RFC2003, RFC2004, RFC2107, RFC2344, RFC2401, RFC2406, RFC2473 and RFC2529 (all of which are hereby incorporated by reference) relate to the subject of tunneling. For example, RFC1234 presents a method of tunneling IPX frames over UDP. In that method, packets are tunneled to a fixed UDP port and to the decapsulator's IP address.
The IPSEC protocol mentioned in the background description typically uses the Internet Key Exchange or IKE protocol (known from references RFC2409, RFC2408 and RFC2407, all of which are hereby incorporated by reference) for authenticating the communicating parties to each other, deriving a shared secret known only to the communicating parties, negotiating authentication and encryption methods to be used for the communication, and agreeing on a security parameter index (SPI) value and a set of selectors to be used for the communication. The IKE protocol was previously known as the ISAKMP/Oakley, where the acronym ISAKMP comes from Internet Security Association Key Management Protocol. Besides said normal negotiation specified in the IKE standard, IKE supports certain mechanisms for extension. The Vendor ID payload known from reference RFC2408, which is hereby incorporated by reference, allows communicating parties to determine whether the other party supports a particular private extension mechanism. The IPSEC DOI (Domain of Interpretation) known as RFC2407, which is hereby incorporated by reference, reserves certain numeric values for such private extensions.
Currently, the well-known Vendor ID payload is defined to have the format illustrated in FIG. 2 a , where the column numbers correspond to bit positions.
For the purposes of the present invention the Vendor ID field 201 is the most important part of the Vendor ID payload. In the context of the IKE protocol, negotiating whether the remote host supports a certain method for providing secure network communications can be performed as follows. The terminology used here is borrowed from the IKE documents.
The IKE protocol determines the so-called Phase 1 of the mutual exchange of messages between the Initiator (i.e., the node first sending a packet to the other) and the Responder (i.e., the node first receiving a packet). FIG. 3 illustrates an exchange of first Phase 1 messages between the Initiator and the Responder. According to the “methods supported” aspect of the invention both devices include a certain Vendor ID Payload in a certain Phase 1 message which is most advantageously their first Phase 1 message. This payload indicates that they support the method in question.
In FIG. 3 the Vendor ID fields contained within the Initiator's first (or other) Phase 1 message is schematically shown as 201 ′ and the Vendor ID fields contained within the Responder's first (or other) Phase 1 message is schematically shown as 201 ″. To indicate support for a certain method the Vendor ID field in the Vendor ID Payload is basically an identification of that method: advantageously it is the MD5 hash of a previously known identification string, e.g. “SSH IPSEC NAT Traversal Version 1”, without any trailing zeroes or newlines. Producing MD5 hashes of arbitrary character sequences is a technique well known in the art for example from the publication RFC1321, which is hereby incorporated by reference, mentioned in the list of references.
Next we will address the “occurring translations” aspect of the invention. In addition to the above-mentioned Phase 1, the IKE protocol determines the so-called Phase 2 of the mutual exchange of messages between the Initiator and the Responder. According to the “occurring translations” aspect of the invention the parties can determine which translations occur by including the IP addresses they see in private payloads of certain Phase 2 Quick Mode messages, which are most advantageously their first Phase 2 Quick Mode messages. Any unused number in the private payload number range can be used to signify such use of the private payload (e.g. 157, which is unused at the priority date of the present patent application).
The private payload used to reveal the occurring translations can have e.g. the format illustrated in FIG. 2 b . Field 211 contains a type code that identifies the types of the addresses that appear in fields 212 and 213 . Field 212 contains the address of the Initiator as seen by the node sending the message, and field 213 contains the address of the Responder as seen by the node sending the message. FIG. 3 shows the exchange of (first) Phase 2 Quick Mode messages between the Initiator and the Responder so that the corresponding fields 211 ′, 212 ′ and 213 ′ are included in the message sent by the former and the fields 211 ″, 212 ″ and 213 ″ are included in the message sent by the latter.
According to known practice the addresses of the Initiator and Responder are also included in the header of the packet that contains the payload of FIG. 2 b . In the header they are susceptible to address translations and other processing whereas in the private payload they are not. When the packet with the payload of FIG. 2 b is received, the addresses contained in it are compared with those seen in the packet header. If they differ, then an address translation occurred on the packet. Later we will refer to the use of the standard IKE port number 500 together with applying the invention; as an additional way of detecting occurred translations the port numbers of the received packet can also be compared against the standard IKE port number 500 to determine if port translations occurred.
An aspect of some importance when handling the addresses is that the UDP source port of the packet can be saved for later use. It would usually be saved with the data structures for Phase 1 ISAKMP security associations, and would be used to set up compensation processing for Phase 2 IPSEC security associations.
To use the method described above to implement the “occurred translations” aspect of the invention, the hosts must modify their Phase 2 identification payloads: the payload illustrated in FIG. 2 b is not known in the existing standards. One possibility is to restrict the payloads to the ID_IPV4_ADDR and ID_IPV6_ADDR types, which would be appropriate for host-to-host operation.
Next we will address the “selected tunnelling”, “compensation/authentication” and “compensation/mapping” aspects of the invention. According to this aspect of the invention the actual data packets can be tunneled over the same connection which is used to set up the security features of the communication connection, e.g. the UDP connection used for IKE. This ensures that the actual data packets will experience the same translations as the IKE packets did when the translation was determined. Taken that the standard port number 500 has been determined for IKE, this would mean that all packets are sent with source port 500 and destination port 500, and a method is needed to distinguish the real IKE packets from those containing encapsulated data. One possible way of doing this takes advantage of the fact that the IKE header used for real IKE packets contains an Initiator Cookie field: we may specify that Initiators that support this aspect of the invention never generate cookies that have all zeroes in their four first bytes. The value zero in the corresponding four bytes is then used to recognize the packet as a tunneled data packet. In this way, tunneled data packets would have four zero bytes at the beginning of the UDP payload, whereas real IKE packets never would.
FIG. 4 illustrates the encapsulation of actual IPSEC packets into UDP for transmission. Basically, a UDP header 403 and a short intermediate header 404 are inserted after the IP header 401 already in the packet (with the protocol field copied to the intermediate header). The IP header 401 is slightly modified to produce a modified IP header 401 ′. The IP payload 402 stays the same. The simple illustration of the unencapsulated IPSEC packet on the left should not be misinterpreted: this packet is not plaintext but has been processed according to AH or ESP or corresponding other transformation protocol in the sending node before its encapsulation into UDP.
Without limiting the generality, it is assumed in the presentation here that the encapsulation according to FIG. 4 is always performed by the same nodes that perform IPSEC processing (either an end node or a VPN device). It should also be noted that instead of encapsulating the IPSEC packets into UDP they could be encapsulated into TCP. This alternative would probably require using fake session starts and ends so that the first packet has the SYN bit and the last packet has the FIN bit, as specified in the TCP protocol.
In encapsulating an actual data packet or a “datagram” according to FIG. 4 , the original IP header 401 —defined in RFC791, which is hereby incorporated by reference,—is modified to produce the modified IP header 401 ′ as follows:
the Protocol field in the IP header (not separately shown) is replaced by protocol 17 for UDP in accordance with RFC768, which is hereby incorporated by reference, the Total Length field in the IP header (not separately shown) is incremented by the combined size of the UDP and intermediate headers (total 16 bytes) and the Header Checksum field in the IP header (not separately shown) is recomputed in accordance with the rules given in RFC791, which is hereby incorporated by reference.
As seen from FIG. 4 , an UDP header 403 —as defined in RFC768, which is hereby incorporated by reference,—and an intermediate header 404 are inserted after the IP header. The UDP header is 8 octets and the intermediate header is 8 octets, for a total of 16 octets. These headers are treated as one in the following discussion. The combined header has most advantageously the format illustrated in FIG. 2 c . Fields of this header are set as follows:
The Source Port field 221 is set to 500 (same as IKE). If the packet goes through NAT, this may be different when the packet is received. The Destination Port field 222 is set to the port number from which the other end appears to be sending packets. If the packet goes through NAT, the recipient may see a different port number here. The UDP Length field 223 is the length of the UDP header plus the length of the UDP data field. In this case, it also includes the intermediate header. The value is computed in bytes as 16 plus the length of the original IP packet payload (not including the original IP header, which is included in the Length field in the IP header). The UDP Checksum field 224 is most advantageously set to 0. The UDP checksum is optional, and we do not wish to calculate or check it with this tunneling mechanism. Integrity of the data is assumed to be protected by an AH or ESP header within the tunneled packet. The Must be zero field 225 : This field must contain a previously agreed fixed value, which is most advantageously all zeroes. The field overlaps with the first four bytes of the Initiator Cookie field in an actual IKE header. Any Initiator that supports this aspect of the invention must not use a cookie where the first four bytes are zero. These zero bytes are used to separate the tunneled packets from real ISAKMP packets. Naturally some other fixed value than “all zeroes” could be chosen, but the value must be fixed for this particular use. Protocol field 226 : The value of this field is copied from the known Protocol field in the original IP header (not separately shown in FIG. 4 ). Reserved field 227 : most advantageously sent as all zeroes; ignored on reception.
The sender inserts this header in any packets tunneled to a destination behind NAT. Information about whether NAT is used can be stored on a per SA (Security Association) basis in the policy manager. The encapsulation referred to in FIG. 4 can be implemented either as a new transform or as part of the otherwise known AH and ESP transforms.
The encapsulation operation makes use of the UDP port number and IP address of the remote host, which were determined during the IKE negotiation.
The receiver decapsulates packets from this encapsulation before doing AH or ESP processing. Decapsulation removes this header and updates the Protocol, Length, and Checksum fields of the IP header. No configuration data (port number etc.) is needed for this operation.
The decapsulation should be performed only if all of the following selectors match:
destination address is the destination address of this host, source address is the address of a host with which this host has agreed to use this tunnelling, the Protocol field indicates UDP, the Destination port field value is 500 and the Source port field value indicates the port with which this host has agreed to use this tunneling. (Note that there may be multiple source addresses and ports for which this tunneling is performed; each of them is treated by a separate set of selectors.)
During decapsulation the source address in the received packet can be replaced by the real source address received during the IKE negotiation. This implements the compensation for AH MAC verification. The address is again changed in the post-processing phase below. Because of this compensation, the standard AH and ESP transforms can be used unmodified.
In FIG. 3 the AH/ESP processing at the sending node is schematically shown as block 301 , encapsulation of datagrams into UDP is schematically shown as block 302 , the corresponding decapsulation of datagrams from UDP is schematically shown as block 303 and AH/ESP processing at the receiving node is schematically shown as block 304 .
Additional compensation must be done after the packet has been decapsulated from AH or ESP. This additional decapsulation must deal with the fact that the outer packet actually went through NAT (illustrated schematically in FIG. 3 as block 305 ), and consequently the plaintext packet must also undergo a similar transformation. The recipient must see the address of the NAT device as the address of the host, rather than the original internal address. Alternatively, this compensation could have been performed by the sender of the packet before encapsulating it within AH or ESP.
There are several alternatives for this additional compensation for various special cases (the best compensation depends on the particular application):
Allocating a range of network addresses for this processing (say, in the link-local use range 169.254.x.x—the actual values do not matter; basically we just want an arbitrary network that no-one else is using). An address in this range is allocated for each <natip, ownip, natport, ownport> combination, where natip means the IP address of the NAT, ownip means the processing device's own IP address, natport means the port number at the NAT and own port means the processing device's own port number. The remote address in the packet is replaced by this address before the packet is sent to protocol stacks. As part of the compensation, the TCP checksum for internal hosts must be recomputed if host addresses or port numbers changed. TCP checksum computations may also be incremental, as is known from RFC1071, which is hereby incorporated by reference. Port NAT may need to be performed for the source port. When used as a VPN between two sites using incompatible (possibly overlapping) private address spaces, address translation must be performed to make the addresses compatible with local addresses. When used as a VPN between two sites using compatible (non-overlapping) private address spaces, and tunnel mode is used, no additional compensation may be needed. Address translation may need to be performed for the contents of certain protocol packets, such as FTP (known from RFC959, which is hereby incorporated by reference) or H.323. Other similar issues are discussed in the reference given as HoldregeSrisuresh99. It may also be possible to use random addresses for the client at the server, and perform address translation to this address. This could allow the server to distinguish between multiple clients behind the same NAT, and could avoid manual configuration of the local address space. The compensation operation may or may not interact with the TCP/IP stack on the local machine to reserve UDP port numbers.
In general, this invention does not significantly constrain the method used to compensate for inner packets the NAT occurring for the outer header. The optimal method for performing such compensation may be found among the above-given alternatives by experimenting, or some other optimal method could be presented.
Next we will address the “keepalive” aspect of the invention, i.e. ensuring that the network address translations performed in the network do not change after the translations that occur have been determined. Network address translators cache the information about address mapping, so that they can reverse the mapping for reply packets. If TCP is used, the address translator may look at the FIN bit of the TCP header to determine when it can drop a particular mapping. For UDP, however, there is no explicit termination indication for flows. For this reason, many NATs will time out mappings for UDP quite fast (even as fast as in 30 seconds). Thus, it becomes necessary to force the mapping to be maintained.
A possible way of ensuring the maintaining of mappings is to send keepalive packets frequently enough that the address translation remains in the cache. When computing the required frequency, one must take into account that packets may be lost in the network, and thus multiple keepalives must be sent within the estimated shortest period in which NATs may forget the mapping. The appropriate frequency depends on both the period the mappings are kept cached and on the packet loss probability of the network; optimal frequency values for various context may be found through experimenting.
Keepalive packets do not need to contain any meaningful information other than the necessary headers that are equal to the data packet headers to ensure that the keepalive packets will be handled exactly in the same way as the actual data packets. A keepalive packet may contain an indicator that identifies it as a keepalive packet and not a data packet; however it may also be determined that all packets that do not contain meaningful payload information are interpreted to be keepalive packets. In FIG. 3 the transmission of keepalive packets is schematically illustrated by block 306 and the reception and discarding of them is schematically illustrated by block 307 . It should be noted that the use of keepalive packets is not needed at all if actual data packets are transmitted frequently enough and/or the connection is to remain valid only for such a short time (e.g. a few seconds) that it is improbable that any intermediate device would delete the mapping information from its cache. Keepalive packets need to be transmitted in one direction only, although they may be transmitted also bidirectionally; the drawback resulting from their bidirectional transmission is the resulting increase in unnecessary network traffic. The invention does not limit the direction(s) in which keepalive packets (if any) are transmitted.
FIG. 5 is a simplified block diagram of a network device 500 that can act as the Initiator or the Responder according to the method of providing secure communications over network address translations in accordance with the invention. Network interface 501 connects the network device 500 physically to the network. Address management block 502 keeps track of the correct network addresses, port numbers and other essential public identification information of both the network device 500 itself and its peer (not shown). IKE block 503 is responsible for the key management process and other activities related to the exchange of secret information.
Encryption/decryption block 504 implements the encryption and decryption of data once the secret key has been obtained by the IKE block 503 . Compensation block 505 is used to compensate for the permissible transformations in the transmitted and/or received packets according to the invention. Either one of blocks 504 and 505 may be used to transmit, receive and discard keepalive packets. Packet assembler/disassembler block 506 is the intermediator between blocks 502 to 505 and the physical network interface 501 . All blocks operate under the supervision of a control block 507 which also takes care of the routing of information between the other blocks and the rest of the network device, for example for displaying information to the user through a display unit (not shown) and obtaining commands from the user through a keyboard (not shown). The blocks of FIG. 5 are most advantageously implemented as pre-programmed operational procedures of a microprocessor, which implementation is known as such to the person skilled in the art. Other arrangements than that shown in FIG. 5 may as well be used to reduce the invention into practice.
Even though the present invention was presented in the context of IKE, and tunneling using the IKE port, it should be understood that the invention applies to also other analogous cases using different packet formatting methods, different negotiation details, a different key exchange protocol, or a different security protocol. The invention may also be applicable to non-IP protocols with suitable characteristics. The invention is equally applicable to both IPv4 and IPv6 protocols. The invention is also intended to apply to future revisions of the IPSEC and IKE protocols.
It should also be understood that the invention can also be applied to protocol translations in addition to just address translations. Adapting the present invention to protocol translations should be well within the capabilities of a person skilled in the art given the description here and the discussions regarding protocol translation in the former patent applications of the same applicant mentioned above and incorporated herein by reference.
List of References
All of the following references are hereby incorporated by reference.
BorellaLo99 M. Borella, J. Lo: Realm Specific IP: Protocol Specification, draft-ietf-nat-rsip-protocol-00.txt, Work in Progress, Internet Engineering Task Force, 1999.
HoldregeSrisuresh99
M. Holdrege, P. Srisuresh: Protocol Complications with the IP Network Address Translator (NAT), draft-ietf-nat-protocol-complications-00.txt, Work in Progress, Internet Engineering Task Force, 1999.
LoBorella99
J. Lo, M. Borella: Real Specific IP: A Framework, draft-ietf-nat-rsip-framework-00.txt, Work in Progress, Internet Engineering Task Force, 1999.
Rekhter99
Y. Rekhter: Implications of NATs on the TCP/IP architecture, draft-ietf-nat-arch-implications-00.txt, Internet Engineering Task Force, 1999.
RFC768
J. Postel: User Datagram Protocol, RFC 768, Internet Engineering Task Force, 1980.
RFC791
J. Postel: Internet Protocol, RFC 791, Internet Engineering Task Force, 1981.
RFC793
J. Postel: Transmission Control Protocol, RFC 793, Internet Engineering Task Force, 1981.
RFC959
J. Postel, J. Reynolds: File Transfer Protocol, RFC 959, Internet Engineering Task Force, 1985.
RFC1071
R. Braden, D. Borman, C. Partridge: Computing the Internet checksum, RFC 1071, Internet Engineering Task Force, 1988.
RFC1226
B. Kantor: Internet protocol encapsulation of AX.25 frames, RFC 1226, Internet Engineering Task Force, 1991.
RFC1234
D. Provan: Tunneling IPX traffic through IP networks, RFC 1234, Internet Engineering Task Force, 1991.
RFC1241
R. Woodburn, D. Mills: Scheme for an internet encapsulation protocol: Version 1, RFC 1241, Internet Engineering Task Force, 1991.
RFC1321
R. Rivest: The MD5 message-digest algorithm, RFC 1321, Internet Engineering Task Force, 1992.
RFC1326
P. Tsuchiya: Mutual Encapsulation Considered Dangerous, RFC 1326, Internet Engineering Task Force, 1992.
RFC1631
K. Egevang, P. Francis: The IP Network Address Translator (NAT), RFC 1631, Internet Engineering Task Force, 1994.
RFC1701
S. Hanks, T. Li, D. Farinacci, P. Traina: Generic Routing Encapsulation, RFC 1701, Internet Engineering Task Force, 1994.
RFC1702
S. Hanks, T. Li, D. Farinacci, P. Traina: Generic Routing Encapsulation over IPv4 networks, RFC 1702, Internet Engineering Task Force, 1994.
RFC1853
W. Simpson: IP in IP Tunneling, RFC 1853, Internet Engineering Task Force, 1995.
RFC2003
C. Perkins: IP Encapsulation within IP, RFC 2003, Internet Engineering Task Force, 1996.
RFC2004
C. Perkins: IP Encapsulation within IP, RFC 2004, Internet Engineering Task Force, 1996.
RFC2107
K. Hamzeh: Ascend Tunnel Management Protocol, RFC 2107, Internet Engineering Task Force, 1997.
RFC2344
G. Montenegro: Reverse Tunneling for Mobile IP, FC 2344, Internet Engineering Task Force, 1998.
RFC2391
P. Srisuresh, D. Gan: Load Sharing using IP Network Address Translation (LSNAT), RFC 2391, Internet Engineering Task Force, 1998.
RFC2401
S. Kent, R. Atkinson: Security Architecture for the Internet Protocol, RFC 2401, Internet Engineering Task Force, 1998.
RFC2402
S. Kent, R. Atkinson: IP Authentication Header, RFC 2402, Internet Engineering Task Force, 1998.
RFC2406
S. Kent, R. Atkinson: IP Encapsulating Security Payload, RFC 2406, Internet Engineering Task Force, 1998.
RFC2407
D. Piper: The Internet IP Security Domain of Interpretation for ISAKMP. RFC 2407, Internet Engineering Task Force, 1998.
RFC2408
D. Maughan, M. Schertler, M. Schneider, J. Turner: Internet Security Association and Key Management Protocol (ISAKMP), RFC 2408, Internet Engineering Task Force, 1998.
RFC2409
D. Hakins, D. Carrel: The Internet Key Exchange (IKE), RFC 2409, Internet Engineering Task Force, 1998.
RFC2473
A. Conta, S. Deering: Generic Packet Tunneling in IPv6 Specification, RFC 2473, Internet Engineering Task Force, 1998.
RFC2529
B. Carpenter, C. Jung: Transmission of IPv6 over IPv4 Domains without Explicit Tunnels, RFC 2529, Internet Engineering Task Force, 1999.
Srisuresh98Terminology
P. Srisuresh: IP Network Address Translator (NAT) Terminology and Considerations, draft-ietf-nat-terminology-01.txt, Work in Progress, Internet Engineering Task Force, 1998.
Srisuresh98Security
P. Srisuresh: Security Model for Network Address Translator (NAT) Domains, draft-ietf-nat-security-01.txt, Work in Progress, Internet Engineering Task Force, 1998.
SrisureshEgevang98
P. Srisuresh, K. Egevang: Traditional IP Network Address Translator (Traditional NAT), draft-ietf-nat-traditional-01.txt, Work in Progress, Internet Engineering Task Force, 1998.
TYS99
W. Teo, S. Yeow, R. Singh: IP Relocation through twice Network Address Translators (RAT), draft-ietf-nat-rnat-00.txt, Work in Progress, Internet Engineering Task Force, 1999. | A method, apparatus, and computer-readable media are presented that provide a configuration for communications through network address translation. The configuration includes receiving, by a computer device, a packet comprising a predetermined value indicating support by a node for an extension of a communications protocol, wherein the communications protocol is used for communications across a network translator device and the extension is capable of traversing network address translation, and in response to said receiving, determining that the node sending the packet supports the extension of the communications protocol. | 7 |
REFERENCE TO RELATED APPLICATION
This application is related to copending applications respectively entitled UNMANNED AIRCRAFT WITH AUTOMATIC FUEL-TO-AIR MIXTURE ADJUSTMENT, Ser. No. 10/255,184; MINIATURE, UNMANNED AIRCRAFT WITH ONBOARD STABILIZATION AND AUTOMATED GROUND CONTROL OF FLIGHT PATH, Ser. No. 10/255,183; MANUALLY DISASSEMBLED AND READILY SHIPPABLE MINIATURE, UNMANNED AIRCRAFT WITH DATA HANDLING CAPABILITY, Ser. No. 10/255,182; ENGINE DRIVEN SUPERCHARGER FOR AIRCRAFT, Ser. No. 10/255,189; CABLE CONNECTIONS BETWEEN AN UNMANNED AIRCRAFT AND A DETACHABLE DATA HANDLING MODULE, Ser. No. 10/255,187; ELECTRICAL POWER SUPPLY SYSTEM FOR UNMANNED AIRCRAFT, Ser. No. 10/255,188; and MINIATURE, UNMANNED AIRCRAFT WITH INTERCHANGEABLE DATA MODULE, Ser. No. 10/255,186, all filed of even date herewith and which are incorporated herein by reference, and to copending Ser. No. 60/324,931, filed Sep. 27, 2001.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to miniature, unmanned aircraft which are remotely controlled, and more particularly to such aircraft having an on-board parachute and associated deployment system.
2. Description of the Prior Art
Miniature, unmanned aircraft of the type known as “model” aircraft, typically remotely controlled by radio frequency signals, have long been utilized by hobbyists among others. Their practicality has led to suggestions that such aircraft be utilized for data acquisition missions such as remote surveillance. This has traditionally been done by manned conventional aircraft and by satellite. Although both types of platforms are effective, both are quite expensive and limited in their abilities. Miniature, unmanned aircraft would be vastly more practical and lower in cost for most civilian applications.
This has led to remotely controlled model aircraft being suggested for use in aerial data collection. U.S. Pat. No. 6,062,176, issued to Lee Berger on May 16, 2000, and U.S. Pat. No. 5,537,909, issued to Arthur J. Schneider et al., both describe use of model or miniaturized aircraft in data imagery acquisition. Berger's invention is an engine suitable for small aircraft which could be utilized for photoreconnaissance. Schneider et al. utilize a miniature reconnaissance aircraft which is carried to the subject area of interest on another aircraft.
As utilized by hobbyists, model aircraft are controlled on a visual line-of-sight basis, and are flown in most cases on courses dedicated to use of model aircraft by those having experience and familiarity with miniature aircraft. Expansion of the use of miniature, unmanned aircraft over areas not solely dedicated to such aircraft introduces concerns for safety. Because many if not almost all model aircraft are capable of considerable airspeeds, some attaining close to two hundred miles per hour, it will be appreciated that a parachute system for slowing an aircraft which is no longer under close control of the operator would be highly advisable.
Neither Berger nor Schneider addresses the need for parachutes. There exists a need to provide miniature, unmanned aircraft suitable for use in collection of aerial data in commercial and other civil applications with an automatically deployed parachute system.
SUMMARY OF THE INVENTION
The present invention improves upon small scale, unmanned aircraft used in hobby flight, reconnaissance, and in image acquisition. Model aircraft and other miniature, unmanned aircraft are typically light enough to avoid the fifty-five pound limit which is a threshold above which severe restrictions on use of an aircraft are imposed. As employed herein, a miniature aircraft will be understood to be of dimensions too small to accommodate a human occupant who is capable of controlling the flight.
It would greatly reduce costs and increase practicality to perform certain tasks with miniature, unmanned aircraft. Miniature aircraft cost less to purchase, maintain, and operate than full size aircraft which accommodate human occupants. Also, they are not restricted as to storage, take off or launch, and areas of operation. As an illustration of the latter condition of operation, it is noted that miniature aircraft are not restricted as regards being allowed to overfly certain types of facilities. Full size aircraft are, for example, banned over certain populated facilities, and require runways of great length to take off.
However, noting the speeds attainable by miniature aircraft, the present invention seeks to provide miniature aircraft both with parachutes and also with an automatic deployment system which can deploy a parachute in certain predetermined situations. Such a system not only promotes public safety, but also has the potential to promote public perception of increased safety. The latter will lead to greater public acceptance of miniature aircraft as utilized away from small, dedicated courses, thereby promoting the many benefits which can be realized by miniature aircraft.
Accordingly, it is an object of the invention to provide an automatically deployed parachute for miniature aircraft which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
Another object is to promote both public safety and also public perception of safety.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.
BRIEF DESCRIPTION OF THE DRAWING
Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawing, which is a diagrammatic, side elevational view of one embodiment of an aircraft according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The drawing figure shows a miniature, unmanned, remotely guided or controlled aircraft 10 having an automatic parachute deployment system according to the present invention. Aircraft 10 is too small to accommodate an adult human operator, and preferably weighs less than fifty-five pounds. Particularly addressing civilian uses in the United States, it is highly desirable to have an unmanned aircraft which is light enough to avoid the fifty-five pound limit which is a threshold above which severe restrictions on use of an aircraft are imposed. Aircraft 10 has an airframe including a fuselage 12 and a wing 14 for developing lift, and has a reciprocating piston internal combustion engine 16 drivably connected to a propeller 18 . A radio frequency receiver 20 is disposed to receive remote guidance signals.
Aircraft 10 has a flight control system disposed to control direction of flight responsive to the remote guidance signals. The flight control system includes a flight control element comprising at least one of the group including rudder, elevator, flaps, and ailerons. The flight control system also includes servomechanisms for driving the rudder, elevator, flaps, and ailerons. These control components are shown symbolically as rudder 22 and servomechanism 24 . The control components and their associated servomechanisms may be generally similar to those employed for so called “model” aircraft.
Unlike most model aircraft flown by hobbyists and for simulation in movie making, aircraft 10 has a microprocessor 26 for managing flight control by sending control signals to servomechanism 24 and for performing other supervisory tasks. Radio receiver 20 is communicably connected to microprocessor 26 . An engine driven generator 28 provides electrical power for operating microprocessor 26 and all other electrically operated devices such as receiver 20 and servomechanism 24 either directly or indirectly through a battery (not shown).
A parachute 30 , shown folded and contained within a receptacle 32 , is carried aboard the airframe in any suitable location. Parachute 30 will be understood to include a sturdy tether (not shown) anchored to the airframe, and is preferably of sufficient size and configuration as to be able to slow aircraft 10 to a speed not exceeding approximately sixteen feet per second. A deployment system is disposed to deploy parachute 30 under at least one predetermined condition. The deployment system includes a parachute deployment mechanism such as pyrotechnic device 34 operated by an ignitor 36 . Pyrotechnic device 34 may be similar to those employed to operate automotive airbags used for passenger restraint in the event of collision. Pyrotechnic device 34 may optionally include or omit a flexible bag (not separately shown) for enclosing gas generated by operation. Ignitor 36 is operated by an electrical signal originating at microprocessor 26 or alternatively, at a microprocessor subsystem 38 , as will be explained hereinafter.
At least one sensor is provided and is disposed to sense a threshold value of at least one operational parameter of flight upon which a decision to deploy parachute 30 is based. That sensor or another sensor causes the parachute deployment mechanism (in the embodiment shown in FIG. 1, this being pyrotechnic device 34 and ignitor 36 ) to operate. Although a sensor may act directly on the parachute deployment mechanism, thereby bypassing microprocessor 26 , it is preferred to utilize microprocessor 26 to manage the deployment process and to generate the necessary signal to ignitor 36 if microprocessor 26 also manages flight. When microprocessor 26 manages both flight and also parachute deployment, microprocessor 26 causes the deployment mechanism to operate responsive to sensing when a sensed threshold value falls below or above a predetermined magnitude, or otherwise is outside a predetermined acceptable range of values.
For example, the decision to deploy parachute 30 may be based on engine failure. A tachometer 40 monitors generator 28 and transmits a data signal indicative of sensed engine speed to microprocessor 26 . Microprocessor 26 will be understood to include memory and programming (neither shown) which include a predetermined minimum engine speed threshold value. Microprocessor is programmed to compare data received from sensor 40 with threshold values stored in memory. Should the engine speed, typically reported as revolutions per minute of the crankshaft (not separately shown), fall below the minimum threshold value stored in memory, it may be inferred that the engine has failed, and a deployment decision is made responsively by microprocessor 26 . In the example just described, engine speed is the monitored operating parameter.
Operation of microprocessor 26 , when the latter manages flight, as occurs in the preferred embodiment, is also selected as an operating parameter. In this case, microprocessor periodically or continuously generates a deployment inhibition signal. The inhibition signal is monitored by subsystem 38 . In the event that the inhibition signal is absent for a predetermined time interval, failure of microprocessor 26 may be inferred, and subsystem 38 generates a deployment signal. When subsystem 38 operates in the fashion described, then microprocessor 26 may generate a deployment signal responsive to sensor 40 by discontinuing the inhibition signal. Subsystem 38 may be regarded as a sensor which monitors successful operation of microprocessor 26 . Subsystem 38 is arranged to operate in a “dead man” or fail safe mode assuring that the decision to deploy parachute 30 not be dependent on a component which itself could conceivably fail.
The fail safe mode may be realized by providing a secondary or dedicated battery 42 , and connecting power of both generator 28 (or its associated principal battery) and also battery 42 to ignitor 36 through normally closed contacts of a relay (not shown) the coil of which is normally energized during flight operation such that the normally closed contacts are open during flight.
Thus a plurality of sensors may be provided, each of which is disposed to monitor and communicate a different operational parameter of flight, with the deployment signal being based on either monitored parameter. Obviously, additional criteria for deploying parachute 30 may be invoked.
It will be recognized that the role of microprocessor 26 may be restricted if desired. For example, flight control components such as rudder 22 and its associated servomechanism 24 could be operated directly from radio receiver 20 , thereby bypassing microprocessor 26 , the latter managing the parachute deployment system only. Alternatively, the parachute deployment system could be arranged to respond directly to a sensor and thereby bypass microprocessor 26 . In such case, deployment threshold recognition would be inherent in or contained within the controlling sensor or sensors, or some intermediary device acted on by the sensor or sensors. It is possible that no microprocessor be provided, or alternatively that a microprocessor be provided but assume a role unrelated either to flight management or to parachute deployment. An example of the latter is to use a microprocessor in managing an image acquisition system (not shown) carried aboard the aircraft.
The deployment system could be based on any system which determines that control of the aircraft is lost or that flight departs from intentional characteristics. For example, should the aircraft exceed a maximum or minimum altitude, an altimeter or other sensor could cause the microprocessor to generate the deployment signal. Should the aircraft stray from a pre-established course, then a received GPS signal which reveals a position deviating within predetermined tolerances of an instructed flight path may be utilized to generate the deployment signal.
It is also possible to generate a deployment signal upon a specific command to do so transmitted from the ground. Such a command may operate the parachute deployment system directly or alternatively, through microprocessor 26 .
The system is arranged to prevent deployment under certain circumstances. For example, on final landing approach or upon landing, it may be desirable to inhibit parachute deployment.
The invention is susceptible to other variations and modifications which may be introduced thereto without departing from the inventive concept. For example, the system comprising pyrotechnic device 34 and ignitor 36 may be replaced by another system achieving a similar function. Illustratively, a pre-compressed elastomeric spring and an associated release device (neither shown) could be provided to deploy parachute 30 . In still another example, a reservoir containing a compressed gas could be utilized in place of pyrotechnic device 34 .
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims. | A miniature, unmanned aircraft having a parachute which deploys automatically under certain conditions. The aircraft has a flight control system based on remotely generated signals, potentially achieves relatively high altitude flight for a remotely controlled aircraft, and can thus operate well beyond line-of-sight control. For safety, an automatically deployed parachute system is provided. The parachute deployment system includes a folded parachute and a propulsion system for expelling the parachute from the aircraft. Preferably, a microprocessor for flight management sends intermittent inhibitory signals to prevent unintended deployment. A deployment signal is generated, illustratively, when the microprocessor fails, when engine RPM fall below a predetermined threshold, and when the aircraft strays from predetermined altitude and course. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to a fluid collecting device for use when disconnecting pipes and in particular to a mud bucket for use in the oil production industry.
As is well known, borehole drilling is generally carried out by means of a drill bit at the end of a string of hollow sections of pipe which are joined by tapered threaded connections. The connections are sufficiently strong to transmit the linear, torsional and bending forces involved in drilling and also provide a mechanical seal to prevent leakage of the drilling mud which is pumped down the drill string to lubricate the bit, balance hydrostatic pressure in the rock formation, and carry the cuttings back to the surface.
Drilling mud can contain a variety of chemicals, and for cost, environmental and safety reasons it is desirable that spillage of mud in the drilling rig should be kept to a minimum. Drill pipes are generally connected together in approximately 27-meter long “stands” consisting of three 9-meter lengths. Depending on its internal diameter, each stand can contain a considerable amount of mud. For example, the internal volume of 27 meters of pipe with a mean internal diameter of 63.5 mm is 85.5 liters.
When withdrawing the drill string from a hole, a large proportion of the mud can remain in the drill pipes and would escape when each stand was disconnected unless measures where taken to prevent this from happening. A device commonly used to contain leakage is referred to as a mud bucket and basically consists of shells which are clamped around the drill pipe connection when it has been sufficiently loosened that further rotation requires relatively little torque, but significant leakage has not occurred. A hose is led from the mud bucket to a holding tank to enable the mud collected in the mud bucket to be returned to the holding tank. A mud bucket can be deployed either by suspension from a wire connected to a hoist, or can be automatically moved into position by mechanical arms and other robotic devices.
The shells of a mud bucket are fitted with elastomeric seals to provide a leakage-free fit at the joints with each other and the drill pipe. The shells of the mud bucket may be clamped or closed around the drill pipe manually or by hydraulic or pneumatic actuators. Regardless of the clamping method employed, the shell closing mechanism must be capable of resisting the large force resulting from the pressure exerted by the mud column on the shells. Each meter of mud in the column equates to a pressure of about 0.1 bar when the specific gravity is 1.0. The force on each half of the shell is equal to the projected area multiplied by the total pressure. For example, if the internal diameter of the shells is 300 mm, the height 1.5 meters and the mud column 10 meters, the force on the shells is about 44,000 newtons or 4.4 metric tons.
2. Description of the Prior Art
GB 2300659 describes a mud bucket comprising a can which is longitudinally split into two sections. Each section is provided with a seal along the split, and the two sections are hinged together at a common pivot point. Each section is further connected to an actuator which moves the mud bucket between an open and closed position.
However, in the mud bucket described in GB 23003659, the perpendicular distance between the actuator and the common pivot point between the two sections decreases as the device closes, so that the leverage available to the actuator to close the mud bucket is decreased in the very time at which it is desirable for it to be increased. This means that larger actuators have to be used, or some subsidiary mechanical or hydraulic locking mechanism employed to prevent leakage caused by the internal mud pressure.
All drill pipes are joined together using male and female threads cut into larger diameter sections (or tool joints) at each end. The threads are then tightened up to a very high torque to withstand the linear, torsional and bending forces involved in drilling.
When drill pipe is removed from the bore hole, it is customary to loosen the high torque of the tool joints with two tongs, which can be either manually or hydraulically operated, so that further rotation requires relatively little torque. At this stage little or no mud is leaking from the tool joints, and the mud bucket is clamped around the drill pipe tool joints. Once the mud bucket is installed, a separate hydraulic or pneumatic pipe spinner (or spinning wrench) is used to revolve the upper pipe stand for a number of full turns, and therefore complete the loosening of threads of the tool joints. The spinner rotates the upper drill pipe stand by means of motor driven rollers or chains, while the lower drill pipe is prevented from rotating by the tapered slips used to hold it in position. The upper stand in than lifted up a few centimeters to allow the drilling mud to drain into the mud bucket and through the drain hose to a holding tank.
On manual drilling rigs the pipe spinner is swung into location on the pipe above the mud bucket on a hanging wire attached to a winch by personnel who often have to climb onto the mud bucket to complete the operation. This can be dangerous for personnel if the mud bucket is positioned at an awkward height above the drill floor.
On automatic and semi-automatic drilling rigs it is customary to use a hydraulically powered and positioned device called an iron roughneck that employs a pair of tongs and a pipe spinner, one of whose functions is to provide the loosening and spinning functions described above. Newer models of this device are fitted with an integral mud bucket that can be clamped around the tool joints prior to the final loosening of the tool joints with the device's integral pipe spinner. Older models of this device are not fitted with a mud bucket, and it is not possible for a separate mud bucket to be deployed during the spinning function. This results in significant mud loss onto the drill floor before the separate mud bucket can be deployed.
U.S. Pat. No. 4,643,259 describes a hydraulic drill string breakdown and bleed-off unit which includes a hydraulic drill string disassembly apparatus in combination with a pressure chamber for bleeding off trapped pressure in the drill pipes and a further apparatus for collecting drilling mud from the drill pipes. The unit described in U.S. Pat. No. 4,643,259 employs two tongs for loosening the torque of the tool joints of the drill pipes and is large, heavy, slow, cumbersome and expensive to manufacture.
3. Identification of Objects of the Invention
An object of the invention is to overcome the problems of the prior art by providing a fluid collecting device designed and arranged such that the mechanical advantage of the closing actuator increases as the bucket moves from an open to a closed position.
Another object of the invention is to provide a fluid collection device having an actuator attached to a rigid frame.
Another object of the invention is to provide a fluid collection device housed within a supporting framework to provide operator safety.
Another object of the invention is to provide a fluid collection device in combination with a pipe spinner, housed within a common framework.
SUMMARY OF THE INVENTION
According to the invention there is provided an adjustable fluid collecting device comprising two shells pivotally movable relative to each other wherein the fluid collecting device is movable between an open position in which the shells are distanced from each other and a closed position in which the shells touch and the angle between the lever member and the link member is reduced relative to the angle between the same members when the adjustable fluid collecting device is in its open position.
Preferably, the adjustable fluid collecting device includes two shells pivotally movable relative to each other and a lever member operated by an actuator. The lever member is pivotally connected to a link member which is pivotally connected to at least one of the shells. The lever member is pivotally movable relative to at least one of the shells.
In a second aspect of the invention, an adjustable fluid collecting device includes two shells pivotally movable relative to each other and a lever member operated by an actuator. The lever member is pivotally connected to first and second linking members. The first linking member is pivotally connected to one of the shells. The second linking member is pivotally connected to the other shell so that operation of the actuator results in equal but opposite movement of the shells.
Preferably, the actuator is attached to a rigid frame which substantially surrounds the two shells, actuator and lever assembly. The rigid frame includes bracketing members to which the two shells are pivotally mounted.
Desirably, the second linking member is pivotally connected to the second shell by way of a third linking member, and the second linking member is further pivotally connected to the bracketing member by way of a fourth linking member.
Preferably, the lever member is also pivotably connectable to the bracketing member. Desirably, the lever member is a bellcrank.
Preferably, the adjustable fluid collecting device is used for collecting mud during the disconnection of pipes.
In a third aspect of the invention, a fluid collecting device includes a mud bucket housed within a supporting framework.
In a fourth aspect of the invention, a pipe disconnecting assembly arranged and designed to engage with a plurality of connected pipes includes a rotating means and a fluid collecting device, housed within a single framework, wherein the fluid collecting device is clampable to the connected pipes so that it surrounds the junction therebetween and the rotating means is movable to engage with at least one of the connected pipes so that rotation of the rotating means causes the disconnection of at least one connected pipes, and the fluid collecting device collects any fluid which leaks out of the opened junction between the pipes.
BRIEF DESCRIPTION OF THE DRAWINGS
Three embodiments of the invention will now be discussed by way of example only with reference to the accompanying drawings in which:
FIG. 1 is a top view partially in cross-section of a first embodiment of the adjustable fluid collecting device in an open position around a drill pipe;
FIG. 2 is a top view partially in cross-section of the first embodiment shown in FIG. 1 in a closed position around a drill pipe;
FIG. 3 is a top view partially in cross-section of a second embodiment of the invention in an open position around a drill pipe;
FIG. 4 is a top view partially in cross-section of the second embodiment shown in FIG. 3 in a closed position around a drill pipe; and
FIG. 5 is a perspective view of a pipe disconnecting assembly in accordance with a third embodiment of the invention surrounding an assembly of connecting pipes.
DESCRIPTION OF PREFERRED EMBODIMENTS
Turning to FIG. 1 , a first embodiment of the invention includes two shells 1 and 2 with bottom halves 9 , 10 attached respectively thereto and with the shells fitted with arms 3 and 4 which are hinged at a common pivot point 5 . An actuator 6 operates a bellcrank 12 through a pin 14 . The bellcrank 12 is pivoted at pin 7 on arm 3 . The bellcrank 12 is further connected to a linking member 13 by a pin 15 . The linking member 13 is connected to arm 4 via pin 8 .
Turning to FIG. 2 , when the first embodiment is employed in a closed position around a drill pipe, the angle between the bellcrank 12 and the linking member 13 is significantly less than when the first embodiment is in the open position. Since the force available to close the adjustable fluid collecting device varies inversely with the tangent of half the angle between the bellcrank 12 and the linking member 13 , a large closing force can be generated by a relatively low powered actuator. For example, if the angle between the bellcrank 12 and the linking member 13 is 10 degrees, the force on the pins 7 and 8 is 0.5/tan5=5.72 times the force on the pin 15 created by the actuator 6 . This force can be further increased by making the distance between the pins 14 and 7 greater than the distance between pins 7 and 15 and by increasing the distance between the pins 7 and 8 and the pivot point 5 . The velocity ratio between the actuator 6 and the shells 1 and 2 can be adjusted so that the closing mechanism is irreversible. In such case, the shells 1 and 2 are locked into their closed position without the use of any subsidiary mechanism.
A second embodiment of the adjustable fluid collecting device is illustrated in FIG. 3 . Shells 101 and 102 with bottom halves 9 , 10 are fitted with arms 103 and 104 and pivoted on pins 17 and 18 mounted on a bracket 19 . An actuator 106 is attached to a rigid frame 20 by a pin 21 and operates a bellcrank 112 via a pin 22 . The bellcrank 112 is attached to bracket 19 by a pin 23 , and to linking members 24 and 25 by a pin 26 . The other end of linking member 24 is attached to the arm 103 by a pin 27 . Linking member 25 is connected to linking members 28 and 29 by pin 30 . The other end of linking member 28 is attached to bracket 19 by pin 31 . The other end of linking member 29 is attached to arm 104 by pin 32 . Linking members 24 , 28 and 29 are arranged in length such that movement of the bellcrank 112 results in equal but opposite movement of the shells 101 and 102 .
As illustrated in FIG. 4 , the second embodiment employs the same principal as that employed by the first embodiment: increasing the closing force on the shells 101 and 102 by reducing the angle between the actuator 106 and the bellcrank 112 and the linking members. In addition to providing an appropriate mounting of the bracket 19 and the actuator 106 , the rigid frame 20 and upper and lower pipe guides (not shown) provide protection for the shells and closing mechanism, provide a safety barrier to protect operators from injury, and facilitates the mounting of the adjustable fluid collecting device on robot arms or other devices providing automatic or semi-automatic operation.
In general terms, the first and second embodiments employ an operating linkage for a mud bucket having a mechanical advantage that increases as the shells close, thereby providing an energy efficient means of closing a mud bucket which does not require the use of large actuators or subsidiary locking mechanisms to prevent drilling-mud leakage.
FIG. 5 shows a third embodiment of the invention in which an upper drill pipe 40 is connected to a lower drill pipe 41 by connections 42 and 43 . A pipe disconnecting assembly comprises a frame 120 supporting shells 201 and 202 of either the first or second embodiments of the adjustable fluid collecting device wherein the shells 201 and 202 are fitted with compliant gaskets 44 and 45 . The shells in FIG. 5 are shown in the open configuration. After the adjustable fluid collecting device has been positioned, hydraulic or pneumatic actuators are used to close the shells 201 and 202 to create a sealed cylindrical container, surrounding the junction between the upper drill pipe 40 and the lower drill pipe 41 . The shells 201 and 202 are further provided with connections 46 for hoses to drain any collected mud to a holding tank.
The frame 120 also supports a housing 47 in which there are rollers 48 and 49 mounted on arms 50 and 51 . The arms are duplicated at each end of the rollers, and there are two rollers per arm. The resulting four rollers 48 and 49 can be forced against the upper drill pipe 40 by hydraulic or pneumatic actuators acting on the arms 50 and 51 . The rollers are also geared together so that they can be rotated in the same direction by a hydraulic or pneumatic rotary activator 52 . The upper drill pipe 40 may thus be rotated by the rollers to disconnect the threads completely. The upper drill pipe is then lifted to allow the mud to escape into the sealed cylindrical contained formed by the closed shells 201 , 202 . After draining via connection 46 , the shells 201 and 202 can then be opened and the whole assembly comprising a mud bucket and spinner withdrawn, ready for the next cycle of operation.
In general, the third embodiment of the invention uses a rigid frame 120 to support a mud bucket and facilitate the accurate operation of the mud bucket relative to the frame, thereby making it easier to deploy the mud bucket automatically by a remote linkage so that the mud bucket is safer to install. As shown in FIG. 5 , frame members 1010 , 1011 , 1012 , 1013 , 1014 , 1015 , 1016 , 1017 , 1018 , 1019 , 1030 , 1031 , and 1032 , among others, are preferably connected together to form frame 120 . Frame 120 preferably includes closed vertical sides 1000 , 1001 , 1004 , open vertical side 1005 , top 1003 , and bottom 1004 . Frame side 1000 has the shape of a closed polygon with edges 1020 , 1021 , 1022 , and 1023 defined by frame members 1010 , 1016 , 1012 , 1017 , respectively. Frame side 1001 has the shape of a closed polygon with edges 1022 , 1026 , 1024 , and 1025 defined by frame members 1012 , 1015 , 1013 , and 1018 , respectively. Likewise, frame side 1004 has the shape of a closed polygon with edges 1024 , 1027 , 1028 , and 1029 defined by frame members 1018 , 1019 , 1011 , and 1014 , respectively. Frame sides 1000 , 1001 , and 1004 include cross frame members 1030 , 1031 , and 1032 , respectively.
The third embodiment of the invention also improves the safety of the operation of a mud bucket by ensuring that the operation of the device is enclosed within the rigid frame, thereby physically protecting operators from the mud bucket. To this end, the rigid frame may also be provided with suitable guarding to enhance safety. Furthermore, the frame can serve as a means of mounting a joint for a spinner.
A fourth embodiment of the invention combines a pipe spinner with the adjustable fluid collecting device of either the first or second embodiments of the invention, housed within a common mounting suitably adapted to withstand the forces involved in the operation of the pipe spinner and adjustable fluid collecting device. The pipe spinner and adjustable fluid collecting device are movable within the housing to the drill pipe either by suspension from a wire connecting to a hoist, or are automatically moveable within the housing to the drill pipe by mechanical arms or other robotic devices. The resulting assembly minimizes mud-loss, speeds up drilling operations, and greatly improves the safety of personnel on manual rigs and rigs with older models of iron rough neck that do not have an integral pipe spinner.
The invention is not limited by the embodiments hereinbefore described but only by the claims presented below. | An adjustable fluid collecting device with two shells pivotally movable relative to each other wherein the fluid collecting device is movable between an open position in which the shells are distanced from each other and a closed position in which the shells touch, an actuator and a lever assembly wherein the operation of the actuator results in equal but opposite movement of the shells and the mechanical advantage increases as the shells move toward the closed position. A rigid frame which substantially surrounds the two shells, actuator and lever assembly is provided. Optionally, the apparatus can be equipped with an integral pipe spinner. | 4 |
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